AeroElectric-Archive.digest.vol-jf

December 24, 2009 - January 06, 2010



      
________________________________________________________________________________
Subject: Re: Was Ammeter Help- Now about switches
From: "user9253" <fran4sew(at)banyanol.com>
Date: Dec 24, 2009
Honeywell AML switches are available in DPDT, either 2 position , or 3 position with center off. The AML24EBA3AC04 can replace the S700-2-7 as used in Z-14 These switches will not replace the S700-2-10. You could use two SPST switches instead, one for Master and one for Alternator. If it is desirable to have the Master switch enable the Alternator switch, then a relay will have to be used behind the panel. But then you add another failure point and cost and weight. Although these switches may be more pleasing to the eye, they might not have the optimum functionality, contact rating and price compared to other switches. Joe http://www.mouser.com/Electromechanical/Switches/Rocker-Switches-Paddle-Switches/_/N-5g2qZscv7?P=1z0sh5hZ1yzvtnwZ1z0x3c8Z1z0z2xk&Keyword=honeywell&FS=True -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278790#278790 ________________________________________________________________________________
From: "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net>
Subject: Electrical: Fire Hazard in Resetting Circuit Breakers
(C/Bs) - General Aviation
Date: Dec 24, 2009
Here is an FAA publication that I received a couple of days ago. Thought there might be some interest in reading. Subject: Electrical: Fire Hazard in Resetting Circuit Breakers (C/Bs) - General Aviation CE-10-11 - Small Airplane/ All/ All Models CE-10-11 - Small/Large Air/ All/ All Models _____ ________________________________________________________________________________
Subject: Re: duracell battery leak
From: "gmcjetpilot" <gmcjetpilot(at)yahoo.com>
Date: Dec 24, 2009
Bob: I like the article and have done many test like that, especially with rechargeable NiMh. I have one complaint, where you say "as Engineers we'er....". Who is "we" engineers? Normally I would not mind, but you in particular, have shown some kind of irrational disrespect and personal animus for any one who is an a true engineer. You went into a long story how you would not hire engineers, as if you had that power. You went on to say you would prefer some one from a vocational school over an engineer with a degree from an accredited University. I know there are people like you, but never heard anyone bash education. Dear Sir, that only shows your ignorance of what an engineer is, making your false association, even in passing, even more egregious. America is falling behind because people are not taking engineering, a very difficult curriculum. To bash engineering, which is part of what made America great, engineering excellence, is really un-American and ignorant. Bob, you don't have an engineering degree. In fact on these forums you have attacked and maligned the engineering profession with vitriolic rants. You really should not "embellish" your qualifications. Engineers go to school and learn math, physics, science and an intensive engineering curriculum. I'm offended you'd even think you are an "engineer". It's just dishonest. You are not a Doctor, Lawyer or Indian Chief either. Is that battery test circuit your original design? You should give credit where it is due. May be you should go back to school and take engineering. May be you will have more respect for them and understand what they do. Here is another link with extensive comparisons of brands of alkaline batteries. http://www.candlepowerforums.com/vb/showthread.php?t=64660 Personally I am sold on NiMh for all my applications. People complain they don't last as long. I suspect they don't have the latest NiMh technology, a good NiMh charger and/or use poor technique in charging and using them. They are so cheap now, if bought in quantity from internet discount stores or eBay. There is no reason not to have a bunch of fully charged AA or AAA batteries ready on standby. Alkaline do have better shelf life and do have longer run life in most applications. Alkaline is a wonderful chemistry for solid battery power. However they are disposable, and it gets expensive replacing them in high use applications. I have some NiMh batteries I first bought around 1999. They finally failed and started to decline. I got my moneys worth. There is no need to pay more than a $1 each or even $1.80 for the higher capacity NiMh AA's and AAA's. It is a worth while investment. Frankly I now only use Alkaline in things that need a new battery every year or two, like my home programmable thermostat or wall mounted outside weather station receiver. I do keep some Alkaline's around for "emergencies". However with all the NiMh fully charged I really don't need them. Merry Christmas every one, fly safe! George MS Mechanical Engineering, ATP, CFI, B737/757/767 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278801#278801 ________________________________________________________________________________
Date: Dec 24, 2009
Subject: Re: duracell battery leak
From: Bill Boyd <sportav8r(at)gmail.com>
Off your meds again, George? I find your "complaint" not worth the occupied bandwidth. Perhaps you could utilize "spread-spectrum" by taking it somewhere else. On Thu, Dec 24, 2009 at 1:08 PM, gmcjetpilot wrote: > gmcjetpilot(at)yahoo.com> > > Bob: > > I like the article and have done many test like that, especially with > rechargeable NiMh. I have one complaint, where you say "as Engineers > we'er....". Who is "we" engineers? Normally I would not mind, but you in > particular, have shown some kind of irrational disrespect and personal > animus for any one who is an a true engineer. You went into a long story > how you would not hire engineers, as if you had that power. You went on > to say you would prefer some one from a vocational school over an > engineer with a degree from an accredited University. I know there are > people like you, but never heard anyone bash education. Dear Sir, that > only shows your ignorance of what an engineer is, making your false > association, even in passing, even more egregious. America is falling > behind because people are not taking engineering, a very difficult > curriculum. To bash engineering, which is part of what made America > great, engineering excellence, is really un-American and ignorant. > > > Bob, you don't have an engineering degree. In fact on these forums you > have attacked and maligned the engineering profession with vitriolic > rants. You really should not "embellish" your qualifications. Engineers go > to school and learn math, physics, science and an intensive engineering > curriculum. I'm offended you'd even think you are an "engineer". It's just > dishonest. You are not a Doctor, Lawyer or Indian Chief either. Is that > battery test circuit your original design? You should give credit where it > is > due. May be you should go back to school and take engineering. May be > you will have more respect for them and understand what they do. > > Here is another link with extensive comparisons of brands of alkaline > batteries. > > http://www.candlepowerforums.com/vb/showthread.php?t=64660 > > > Personally I am sold on NiMh for all my applications. People complain > they don't last as long. I suspect they don't have the latest NiMh > technology, a good NiMh charger and/or use poor technique in charging > and using them. They are so cheap now, if bought in quantity from > internet discount stores or eBay. There is no reason not to have a bunch > of fully charged AA or AAA batteries ready on standby. Alkaline do have > better shelf life and do have longer run life in most applications. > Alkaline > is a wonderful chemistry for solid battery power. However they are > disposable, and it gets expensive replacing them in high use applications. > I have some NiMh batteries I first bought around 1999. They finally failed > and started to decline. I got my moneys worth. There is no need to pay > more than a $1 each or even $1.80 for the higher capacity NiMh AA's and > AAA's. It is a worth while investment. Frankly I now only use Alkaline in > things that need a new battery every year or two, like my home > programmable thermostat or wall mounted outside weather station > receiver. I do keep some Alkaline's around for "emergencies". However > with all the NiMh fully charged I really don't need them. > > Merry Christmas every one, fly safe! > > George > MS Mechanical Engineering, ATP, CFI, B737/757/767 > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=278801#278801 > > ________________________________________________________________________________
Subject: A Christmas Current Regulator for All.....
From: "Eric M. Jones" <emjones(at)charter.net>
Date: Dec 24, 2009
Happy Holidays. This is a noise-free current regulator that will power up to three LEDs in series such as the Cree 350-700 lumens stars. ~2100 (maybe) lumens! I have made a few of these to replace noisey Buck_Pucks. I don't have any plans to sell as a product, but you can make your own or get together with friends and make a bunch (Okay, nerds have odd choices of how to have fun get-togethers). This uses the isolated form of the 317 Regulator. If you use the standard (non-isolated) part it is more trouble. Design notes: This is a modified surface-mount assembly used to keep everything flat against the heat sink. Make sure the 317 gets a dab of heat sink compound. Keep the resistor up in the air. It gets very hot. I recommend flowing epoxy over the pcb and 317 leads. You can use RTV, but don't use J-B Weld (I never thought I'd have to say that...) because it is slightly electrically conductive. Standard issues apply--keep the leads from chaffing. I used rubber grommets super-glued in the fingers of the heat sink. This heat sink is good for 1-3 LEDs at 14.5VDC, or 6 or so at 28VDC. I'll send the ExpressPCB file as an attachment if you email me, but this is easy to carve out of plated circuit board. Only a single-sided board is required, but you'll get a double sided-board from ExpressPCB. Forty-eight circuits for $1.25 each delivered in a few days. Cool.... Aficionados will note that different versions of voltage regulators will work for improved performance in some areas or even higher power. Yes...go for it. -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones(at)charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278813#278813 Attachments: http://forums.matronics.com//files/currentregulators_155.pdf ________________________________________________________________________________
Date: Dec 24, 2009
Subject: Re: duracell battery leak
From: "Matt Prather" <mprather(at)spro.net>
You, sir, get one lump of coal.. Matt- > > > Bob: > > I like the article and have done many test like that, especially with > rechargeable NiMh. I have one complaint, where you say "as Engineers > we'er....". Who is "we" engineers? Normally I would not mind, but you in > particular, have shown some kind of irrational disrespect and personal > animus for any one who is an a true engineer. You went into a long story > how you would not hire engineers, as if you had that power. You went on > to say you would prefer some one from a vocational school over an > engineer with a degree from an accredited University. I know there are > people like you, but never heard anyone bash education. Dear Sir, that > only shows your ignorance of what an engineer is, making your false > association, even in passing, even more egregious. America is falling > behind because people are not taking engineering, a very difficult > curriculum. To bash engineering, which is part of what made America > great, engineering excellence, is really un-American and ignorant. > > > Bob, you don't have an engineering degree. In fact on these forums you > have attacked and maligned the engineering profession with vitriolic > rants. You really should not "embellish" your qualifications. Engineers go > to school and learn math, physics, science and an intensive engineering > curriculum. I'm offended you'd even think you are an "engineer". It's just > dishonest. You are not a Doctor, Lawyer or Indian Chief either. Is that > battery test circuit your original design? You should give credit where it > is > due. May be you should go back to school and take engineering. May be > you will have more respect for them and understand what they do. > > Here is another link with extensive comparisons of brands of alkaline > batteries. > > http://www.candlepowerforums.com/vb/showthread.php?t=64660 > > > Personally I am sold on NiMh for all my applications. People complain > they don't last as long. I suspect they don't have the latest NiMh > technology, a good NiMh charger and/or use poor technique in charging > and using them. They are so cheap now, if bought in quantity from > internet discount stores or eBay. There is no reason not to have a bunch > of fully charged AA or AAA batteries ready on standby. Alkaline do have > better shelf life and do have longer run life in most applications. > Alkaline > is a wonderful chemistry for solid battery power. However they are > disposable, and it gets expensive replacing them in high use applications. > I have some NiMh batteries I first bought around 1999. They finally failed > and started to decline. I got my moneys worth. There is no need to pay > more than a $1 each or even $1.80 for the higher capacity NiMh AA's and > AAA's. It is a worth while investment. Frankly I now only use Alkaline in > things that need a new battery every year or two, like my home > programmable thermostat or wall mounted outside weather station > receiver. I do keep some Alkaline's around for "emergencies". However > with all the NiMh fully charged I really don't need them. > > Merry Christmas every one, fly safe! > > George > MS Mechanical Engineering, ATP, CFI, B737/757/767 > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=278801#278801 > > ________________________________________________________________________________
Subject: Re: duracell battery leak
Date: Dec 24, 2009
From: rgent1224(at)aol.com
Deke Do you still have thatflashlight?? If so send it back to Mag-lite. They'll repace at no charge I've done it Just my $00.0002 Worth Merry Xmas & Happy New Year Dick #606/N20DG -----Original Message----- From: fox5flyer <fox5flyer(at)idealwifi.net> Sent: Wed, Dec 23, 2009 5:46 am Subject: Re: AeroElectric-List: duracell battery leak I had a 3 cell Mag Light with Duracells in it. Following the marketing hy pe I always thought they were the best so I bought them in large packages. Being a plumber I used it on a fairly regular basis and I noticed that I had to bump it sometimes to make it turn on. One day when it wouldn't turn on at all so I pulled the cap and found that the batteries had leake d inside and corroded the whole interior which made them impossible to rem ove. I ended up having the throw it in the bin. No, I didn't leave it on or leave it stored with dead batteries. This wasn't the first time I had an experience with leaking Duracells. Having heard about this previously I decided at that moment that the best fix for me was to discontinue all use of Duracells and let others know of my problem with them. If enough folks stop using them they'll soon fix the problem...in the form of "new and improved ultra..." Deke ======================== =========== - -= -- Please Support Your Lists This Month -- -= (And Get Some AWESOME FREE Gifts!) - -= November is the Annual List Fund Raiser. Click on -= the Contribution link below to find out more about -= this year's Terrific Free Incentive Gifts provided -= by: -= * AeroElectric www.aeroelectric.com -= * The Builder's Bookstore www.buildersbooks.com -= * HomebuiltHELP www.homebuilthelp.com -= * HowToCrimp www.howtocrimp.com - -= List Contribution Web Site: - -= --> http://www.matronics.com/contribution - -= Thank you for your generous support! - -= -Matt Dralle, List Admin. - -======================== ======================== =========== -= - The AeroElectric-List Email Forum - -= Use the Matronics List Features Navigator to browse -= the many List utilities such as List Un/Subscription, -= Archive Search & Download, 7-Day Browse, Chat, FAQ, -= Photoshare, and much much more: - -= --> http://www.matronics.com/Navigator?AeroElectric-List - -======================== ======================== =========== -= - MATRONICS WEB FORUMS - -= Same great content also available via the Web Forums! - -= --> http://forums.matronics.com - -======================== ======================== =========== ________________________________________________________________________________
Subject: Re: duracell battery leak
From: "gmcjetpilot" <gmcjetpilot(at)yahoo.com>
Date: Dec 24, 2009
Thanks for your kind comments trolls and Bob's girlfriends. Merry Christmas. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278822#278822 ________________________________________________________________________________
From: Speedy11(at)aol.com
Date: Dec 24, 2009
Subject: Re: Battery leakage
Regardless, many of us ARE having leakage problems. I discovered my high dollar LED flishlight (used frequently and batteries changed often) "welded" closed due to battery leakage just one week ago. I couldn't get the batteries out and threw away the flashlight. I had changed from ever using Duracells again and the faulty batteries this time were Everready. Someone mentioned last week on this forum that the problem might not be with a particular brand, but with alkalines in general. I'm beginning to think there may be some validity to that argument. Or perhaps the problem is caused by the "cheaper" manufacturing process. Perhaps the Chinese cannot make leak resistant batteries as well as Americans or Mexicans. Or perhaps the fault lies in the design of the battery. With the correct design, I suspect quality batteries could be built anywhere. Thoughts? Stan Sutterfield If you dig around in my alkaline cell stock that ranges from AAAA to D cells, you'll find a host of different brands. I've not suffered a severe battery leakage event in so long I don't recall the last time. At the same time, we go through batteries pretty quickly. No cell sits around in a seldom used device. The fact that some of us here on the list have suffered a leakage event with a particular brand is not a definitive study of the propensity of that brand for failure. If say 90% of all cells presently occupying the battery box of our favorite accessories are Duracells . . . it's axiomatic that the propensity of any failures will be in Duracells. ________________________________________________________________________________
Date: Dec 24, 2009
From: Ron Quillin <rjquillin(at)gmail.com>
Subject: Re: Battery leakage
At 16:59 12/24/2009, you wrote: >Someone mentioned last week on this forum that the problem might not >be with a particular brand, but with alkalines in general. I'm >beginning to think there may be some validity to that argument. Or >perhaps the problem is caused by the "cheaper" manufacturing >process. Perhaps the Chinese cannot make leak resistant batteries >as well as Americans or Mexicans. Just to add yet additional data, as many certainly could do, I've just had to toss a number of unused HF "Thunderbolt Magnum" AAA's dated 08-1010 due to leakage. Origin, China. I also ordered on special, from an unremembered source, a large quantity (~200) of Rayovac "Maximum PLUS" AAA's and have had to dispose of nearly 20% due to leakage prior to any even being put into service; these with a Dec 2011 expiration date. This -special- turned out to be not-so-special. Origin, USA. These failure rates prompt consideration on just how I may want to manage batteries in devices... Ron Q. ________________________________________________________________________________
Date: Dec 24, 2009
From: <r.r.hall(at)cox.net>
Subject: Re: duracell battery leak and "engineers"
First, Merry Christmas everyone. Second, George, I personnally have, in many ways, similar feelings to Bob towards Engineers. It is not the engineers fault exactly but it seems there are a lot of jobs out there that have little or nothing to do with engineering that people, usually in human resources, have decreed can only be filled by an engineer. There also seems a certian snobbishness among many engineers. Looking at your signature you are apparently a mechanical engineer, working as a pilot, giving an opinion on batteries so it would seem your qualifications to discuss batteries is no greater than anyone elses. At the shipyard where I used to work it was policy that no one could be a manager without an engineering degree. It made no sense that even in the accounting department you had to have an engineering degree to be a manager. Also "engineers" were being hired right out of college to supervise men with 20+ years on the job. As a maintenance planner every job I plan has to be reviewed by an engineer. Sometimes they come up with the most impractical ideas and almost daily show their ignorance of the systems they are supposed to be "experts" on. I have yet to see any of them open a book or do any of those advanced math or physics calculations they learned in college. Long story short my experience has led me to placing engineers almost equal to lawyers. They are invaluable when you really need one but good ones are hard to find and most of the time you can do without them. For the record, and I could be wrong,I do not think Thomas Edison, Eli Whitney, or the Wright Brothers had engineering degrees. Many of the best inventors did not have engineering degrees but much of the building of america could not have been done without engineers building roads, bridges and other infrastructure. Rodney ________________________________________________________________________________
Date: Dec 24, 2009
From: Dennis Golden <dgolden@golden-consulting.com>
Subject: Merry CRISTmas
May God bless you and your families a merry Christmas and prosperous new year. Dennis -- Dennis Golden Golden Consulting Services, Inc. ________________________________________________________________________________
From: "Steve Gregory" <steve(at)stevegregory.us>
Subject: Re: Battery leakage
Date: Dec 24, 2009
I had more than just a leak. I had two Duracell's "explode" in two different smoke detectors at my house. I was sitting quietly reading, and it sounded like a .22 pistol went off. Couldn't figure out where the loud pop came from. It happened the next day as well. I finally found the source (no red power light on the detector). The bottoms of the batteries were blown out. Went online and Goggled "exploding Duracell batteries". I found a lot of articles. No more Duracell's for me. And if I'm not mistaken, Safeway Select brand alkaline batteries are made by Duracell as well. Steve Gregory 925-323-6987 (cell) steve(at)stevegregory.us From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Speedy11(at)aol.com Sent: Thursday, December 24, 2009 4:59 PM Subject: AeroElectric-List: Re: Battery leakage Regardless, many of us ARE having leakage problems. I discovered my high dollar LED flishlight (used frequently and batteries changed often) "welded" closed due to battery leakage just one week ago. I couldn't get the batteries out and threw away the flashlight. I had changed from ever using Duracells again and the faulty batteries this time were Everready. Someone mentioned last week on this forum that the problem might not be with a particular brand, but with alkalines in general. I'm beginning to think there may be some validity to that argument. Or perhaps the problem is caused by the "cheaper" manufacturing process. Perhaps the Chinese cannot make leak resistant batteries as well as Americans or Mexicans. Or perhaps the fault lies in the design of the battery. With the correct design, I suspect quality batteries could be built anywhere. Thoughts? Stan Sutterfield If you dig around in my alkaline cell stock that ranges from AAAA to D cells, you'll find a host of different brands. I've not suffered a severe battery leakage event in so long I don't recall the last time. At the same time, we go through batteries pretty quickly. No cell sits around in a seldom used device. The fact that some of us here on the list have suffered a leakage event with a particular brand is not a definitive study of the propensity of that brand for failure. If say 90% of all cells presently occupying the battery box of our favorite accessories are Duracells . . . it's axiomatic that the propensity of any failures will be in Duracells. ________________________________________________________________________________
Date: Dec 24, 2009
Subject: Re: Battery leakage
From: Richard Girard <jindoguy(at)gmail.com>
I almost hate to write this testimonial but it's true, nonetheless. Several years ago, Bob did a test of various batteries and the best value in that test were the ones from Dollar General. I started using them and have ever since. I've never had one leak, I've had a very few of less than stellar capacity, but in general they have been of outstanding quality and at the best price around, 25 cents apiece for AA and AAA in packs of 20. I do change out batteries fairly often in these two sizes, but I've had the same experience with their C and D's that have been in flashlights for up to two years with no leakage. Wish I could say the same for the Duracells I have to run in my ELT's. I have a very corroded, near new unit on the shelf that had one year old batteries that with the exception of the occasional test were unused. I have no explanation for my experience with Dollar General batteries other than I don't leave dead batteries in devices. Rick Girard On Thu, Dec 24, 2009 at 6:59 PM, wrote: > Regardless, many of us ARE having leakage problems. I discovered my high > dollar LED flishlight (used frequently and batteries changed often) "welded" > closed due to battery leakage just one week ago. I couldn't get the > batteries out and threw away the flashlight. I had changed from ever using > Duracells again and the faulty batteries this time were Everready. > Someone mentioned last week on this forum that the problem might not be > with a particular brand, but with alkalines in general. I'm beginning to > think there may be some validity to that argument. Or perhaps the problem > is caused by the "cheaper" manufacturing process. Perhaps the Chinese > cannot make leak resistant batteries as well as Americans or Mexicans. > Or perhaps the fault lies in the design of the battery. With the correct > design, I suspect quality batteries could be built anywhere. > Thoughts? > Stan Sutterfield > > > If you dig around in my alkaline cell stock that > ranges from AAAA to D cells, you'll find a host of > different brands. I've not suffered a severe battery > leakage event in so long I don't recall the last time. > At the same time, we go through batteries pretty > quickly. No cell sits around in a seldom used > device. > > The fact that some of us here on the > list have suffered a leakage event with a particular > brand is not a definitive study of the propensity > of that brand for failure. If say 90% of all cells > presently occupying the battery box of our favorite > accessories are Duracells . . . it's axiomatic that > the propensity of any failures will be in Duracells. > > > * > > * > > ery few ________________________________________________________________________________
Subject: Re: duracell battery leak
Date: Dec 24, 2009
From: "Perry, Phil" <Phil.Perry(at)netapp.com>
You could do like me. Just add the address to the spam filter. Phil From: Bill Boyd [mailto:sportav8r(at)gmail.com] Sent: Thursday, December 24, 2009 12:28 PM Subject: Re: AeroElectric-List: Re: duracell battery leak Off your meds again, George? I find your "complaint" not worth the occupied bandwidth. Perhaps you could utilize "spread-spectrum" by taking it somewhere else. On Thu, Dec 24, 2009 at 1:08 PM, gmcjetpilot wrote: Bob: I like the article and have done many test like that, especially with rechargeable NiMh. I have one complaint, where you say "as Engineers we'er....". Who is "we" engineers? Normally I would not mind, but you in particular, have shown some kind of irrational disrespect and personal animus for any one who is an a true engineer. You went into a long story how you would not hire engineers, as if you had that power. You went on to say you would prefer some one from a vocational school over an engineer with a degree from an accredited University. I know there are people like you, but never heard anyone bash education. Dear Sir, that only shows your ignorance of what an engineer is, making your false association, even in passing, even more egregious. America is falling behind because people are not taking engineering, a very difficult curriculum. To bash engineering, which is part of what made America great, engineering excellence, is really un-American and ignorant. Bob, you don't have an engineering degree. In fact on these forums you have attacked and maligned the engineering profession with vitriolic rants. You really should not "embellish" your qualifications. Engineers go to school and learn math, physics, science and an intensive engineering curriculum. I'm offended you'd even think you are an "engineer". It's just dishonest. You are not a Doctor, Lawyer or Indian Chief either. Is that battery test circuit your original design? You should give credit where it is due. May be you should go back to school and take engineering. May be you will have more respect for them and understand what they do. Here is another link with extensive comparisons of brands of alkaline batteries. http://www.candlepowerforums.com/vb/showthread.php?t=64660 Personally I am sold on NiMh for all my applications. People complain they don't last as long. I suspect they don't have the latest NiMh technology, a good NiMh charger and/or use poor technique in charging and using them. They are so cheap now, if bought in quantity from internet discount stores or eBay. There is no reason not to have a bunch of fully charged AA or AAA batteries ready on standby. Alkaline do have better shelf life and do have longer run life in most applications. Alkaline is a wonderful chemistry for solid battery power. However they are disposable, and it gets expensive replacing them in high use applications. I have some NiMh batteries I first bought around 1999. They finally failed and started to decline. I got my moneys worth. There is no need to pay more than a $1 each or even $1.80 for the higher capacity NiMh AA's and AAA's. It is a worth while investment. Frankly I now only use Alkaline in things that need a new battery every year or two, like my home programmable thermostat or wall mounted outside weather station receiver. I do keep some Alkaline's around for "emergencies". However with all the NiMh fully charged I really don't need them. Merry Christmas every one, fly safe! George MS Mechanical Engineering, ATP, CFI, B737/757/767 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278801#278801 ="_blank">www.aeroelectric.com ooks.com" target="_blank">www.buildersbooks.com et="_blank">www.homebuilthelp.com "_blank">www.howtocrimp.com ="_blank">http://www.matronics.com/contribution le, List Admin. -List" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List http://forums.matronics.com ________________________________________________________________________________
Date: Dec 24, 2009
From: jerb <ulflyer(at)verizon.net>
Subject: Re: duracell battery leak
Bob, I don't think its an issue of a definitive study but rather experience gained over time. Myself I never used to have problems with Duracells leaking - even if they were dead - now they leak for no determined reason even if not fully discharged. Even new ones used well within there date code in my PDA device leaked. Something with the product has had to been changed to cause them to leak prematurely. My experience with Rayovac's is you could just about guarantee they would leak if left in a flashlight for any period of time. My experience with Energizers has been better than the prior brand but still experienced leakage problems. In the past Duracells seldom ever leaked even if left in equipment for years. Not so anymore, so what is different with them today. From my position I don't have enough knowledge about the engineering and manufacturing aspects of this type of battery product to determine the cause, I can only base it upon my recent experience in last few years to compared to that before then. I had them leak in my PDA, GPS, and a few Mag lites. jerb At 08:08 AM 12/23/2009, you wrote: > > >A few years ago I did a study of variability in various >brands of alkaline batteries. I concluded from the study >that there is no extra value to be realized for the >purchase of batteries that have high-dollar advertising >budgets. See: > >http://www.aeroelectric.com/articles/AA_Bat_Test.pdf > >I suspect that any brand and any size of alkaline cell >is capable of leaking under some conditions. Further, >given today's business environment for farming out >the production about any kind of product, there's >not much you can hang a hat on for stating that >brand D's demonstrable leakage problems will go away >if one moves their loyalty to brand E. > >If you dig around in my alkaline cell stock that >ranges from AAAA to D cells, you'll find a host of >different brands. I've not suffered a severe battery >leakage event in so long I don't recall the last time. >At the same time, we go through batteries pretty >quickly. No cell sits around in a seldom used >device. > >The fact that some of us here on the >list have suffered a leakage event with a particular >brand is not a definitive study of the propensity >of that brand for failure. If say 90% of all cells >presently occupying the battery box of our favorite >accessories are Duracells . . . it's axiomatic that >the propensity of any failures will be in Duracells. > >Bob . . . > > ________________________________________________________________________________
Date: Dec 24, 2009
From: jerb <ulflyer(at)verizon.net>
Subject: Re: Duracell Leaking Batteries
Bob, As for repair they may clean the compartment and contacts with something - for alkaline some form of base neutralizer like vinegar but, once the battery contacts have had the plating eaten off, they will never work as well. With my PDA, they were not fully discharged, in fact some new ones out of the same package laying on the surface on a desk even started to leak and corrode even though they were within there use date. There is something with these batteries either how there now made or what there made of, that must be causing this. jerb > In the mean time, Duracell offers to repair or > replace a damaged appliance in their sales literature > at: > >http://www.duracell.com/procell/about/care.asp > > Now it may be that they could claim no fault if > somehow their analysis says the cell was left > installed long after it was depleted. I.e., flash > lights, radios, etc inadvertently left on or > perhaps the auto off feature isn't working, etc. > > Bob . . . > > ________________________________________________________________________________
From: "n801bh(at)netzero.com" <n801bh(at)NetZero.com>
Date: Dec 25, 2009
Subject: Re: Battery leakage
Stan. I Agree with you 100 %. I too have witnessed a rise in leakage in the last few years and some episodes have been within a short period of time since battery replacement or new start up. I am convinced there is a systematic degrading of battery construction throughout the industry. I have had Duracells, Everready's and other brands fail. Ben Haas www.haaspowerair.com riginal Message ---------- From: Speedy11(at)aol.com Subject: AeroElectric-List: Re: Battery leakage Date: Thu, 24 Dec 2009 19:59:08 EST Regardless, many of us ARE having leakage problems. I discovered my hig h dollar LED flishlight (used frequently and batteries changed often) "w elded" closed due to battery leakage just one week ago. I couldn't get the batteries out and threw away the flashlight. I had changed from eve r using Duracells again and the faulty batteries this time were Everread y.Someone mentioned last week on this forum that the problem might not b e with a particular brand, but with alkalines in general. I'm beginning to think there may be some validity to that argument. Or perhaps the p roblem is caused by the "cheaper" manufacturing process. Perhaps the Ch inese cannot make leak resistant batteries as well as Americans or Mexic ans.Or perhaps the fault lies in the design of the battery. With the co rrect design, I suspect quality batteries could be built anywhere.Though ts?Stan Sutterfield If you dig around in my alkaline cell stock that ranges from AAAA to D cells, you'll find a host of different brands. I've not suffered a severe battery leakage event in so long I don't recall the last time. At the same time, we go through batteries pretty quickly. No cell sits around in a seldom used device. The fact that some of us here on the list have suffered a leakage event with a particular brand is not a definitive study of the propensity of that brand for failure. If say 90% of all cells presently occupying the battery box of our favorite accessories are Duracells . . . it's axiomatic that the propensity of any failures will be in Duracells. ======================== ======================== ======================== ======================== ============ ____________________________________________________________ Nutrition Improve your career health. Click now to study nutrition! http://thirdpartyoffers.netzero.net/TGL2241/c?cp=HItar5ixWEady-UwpHm6Q gAAJ1GgTD6yWnN9nTOcXhzb7nn5AAYAAAAAAAAAAAAAAAAAAADNAAAAAAAAAAAAAAAAAAASQ wAAAAA ________________________________________________________________________________
Date: Dec 25, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: duracell battery leak
At 10:01 PM 12/24/2009, you wrote: > >Bob, >I don't think its an issue of a definitive study but rather >experience gained over time. Myself I never used to have problems >with Duracells leaking - even if they were dead - now they leak for >no determined reason even if not fully discharged. Even new ones >used well within there date code in my PDA device leaked. Well put. The preponderance of experience here on the List is compelling. A great deal of what's accepted as "best practice", "policy", or whatever has been developed over years of crafting successful recipes in the kitchen. Chefs in those kitchens may not be able to articulate the foundations for their success based on the physics but they can certainly demonstrate what has worked . . . and probably many more things that didn't work. It seems that the chefs in Duracell's battery kitchen have lost the touch. It's a certainty that every manufacturer of high- volume, well competed products is always looking for ways to improve market share (increased advertising . . . perhaps reputation for superior quality, etc.). At the same time, they're looking for ways to keep the stock-holders happy. NOT an easy task or everyone could do it. It may well be that the management of once great suppliers of alkaline cells no longer possess the 'magic' that propelled them to center stage in the first place. We've seen it happen many times with many products. We're going to see it in the future. It will be interesting to watch the market dynamic in alkaline cells The majority of cases where product performance is found lacking do not support our own detailed studies of simple-ideas behind a failure to perform. But do ourselves well to avoid demonstrable problem children . . . which is EXACTLY what this List is all about. I regret that I've become ignorant of any such failures in the Duracell kitchen . . . I don't think I've bought more than a few dozen name-brand cells in the last 10 years! Bob . . . ________________________________________________________________________________
Date: Dec 25, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: "engineers"
At 07:25 PM 12/24/2009, you wrote: >First, Merry Christmas everyone. > >Second, George, > >I personally have, in many ways, similar feelings to Bob towards >Engineers. It is not the engineers fault exactly but it seems there >are a lot of jobs out there that have little or nothing to do with >engineering that people, usually in human resources, have decreed >can only be filled by an engineer. There also seems a certain >snobbishness among many engineers. Looking at your signature you are >apparently a mechanical engineer, working as a pilot, giving an >opinion on batteries so it would seem your qualifications to discuss >batteries is no greater than anyone else. Exactly! I'd have to review any words I've written that seem to denigrate engineers in general. I don't harbor such notions now and I don't recall having done so in the past. What I have decried is the manner in which the potential for creativity while expanding personal horizons is quashed by the business models and policies of company management. Beech was very good at turning potentially good designers into paper pushers. When I retired from Beech, the VP of engineering shook my hand . . . congratulated me and asked, "Who do we tap now to do the things you've been doing for us?" I looked over at my chief scientist with raise eyebrows. He shrugged. Out of 800+ engineers (I presume most if not all were degreed) neither he nor I knew of one individual who could step into what I'd been doing for the past 13 years. While acquisition of a diploma can be a solid foundation for launching a career, too often we find careers molded more by policy, procedure, and opportunity (or lack of it). I was exceedingly fortunate that my first jobs offered boundless opportunity. My last job didn't offer opportunity, I had to MAKE it my self. So like the once-great Duracell brand, perhaps well find that Beech is no longer worthy of the marketplace position it once held so capably. I've counseled many young bucks fresh out of school to be cognizant of their progress in ANY direction. When progress stops . . . take action. There was one promising fellow who was interviewing for a job at Beech to whom I suggested he find a company with no more than 100 employees. "Be a big fish in a small pond", I suggested . . . and explained why based on my own career success. He didn't come to work for us. That was about 10 years ago. I trust his horizons run out further today than what we could have offered him at Beech. Bob . . . ________________________________________________________________________________
From: "Ralph & Maria Finch" <ralphmariafinch(at)gmail.com>
Subject: Re: "engineers"
Date: Dec 25, 2009
There has been a general and profound decay and collapse of leadership throughout the United States over the past few decades. Compare the 1960s (when I was growing up) to now. Then: Man on the moon in 8 years; Now: years to produce a rocket that doesn't do more than the Saturn 5. Then: Build the world's best university and freeway system in California; Now: sit around arguing as those same systems decay into mediocrity. Then: exercise fiscal prudence in banking to supply credit for business progress; Now: exercise wild and greedy schemes to ruin the world economy. Then: Start a stupid war half way around the world for nothing. Now: oh, wait, some things remain the same. This is, of course, far beyond engineers. I don't see any permanent improvement happening to our leadership either, most everybody has become hooked on stupid pills. That leaves it to individuals, as Bob N. put. And why not? That's where we started nearly 400 years ago, individuals banding together and bettering their own lot. In my professional life I'm a water resources engineer doing numerical modeling for a large state agency. Leadership has declined over the last 20 years to where it's impossible to get anything quality done through management. But instead of waiting for them to realize what the problems are and providing support, we are moving ahead with crowd-sourcing to check data, review source code, etc. This email list and other forums are a form of the same thing: individuals getting together on our own to improve things for everybody. The need is the same, just the technology different from the Pilgrims. Ralph Finch Davis, California RV-9A QB SA __________ Information from ESET Smart Security, version of virus signature database 4716 (20091225) __________ The message was checked by ESET Smart Security. ________________________________________________________________________________
Date: Dec 25, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: duracell battery leak
At 12:08 PM 12/24/2009, you wrote: Bob: I like the article and have done many test like that, especially with rechargeable NiMh. I have one complaint, where you say "as Engineers we'er....". Who is "we" engineers? Normally I would not mind, but you in particular, have shown some kind of irrational disrespect and personal animus for any one who is an a true engineer. Your penchant for mis-interpreting and/or using facts not in evidence to assign motive to my words is legendary . . . Bob, you don't have an engineering degree. In fact on these forums you have attacked and maligned the engineering profession with vitriolic rants. George, you'll have to be specific. Please link us to any "rant" I may have indulged myself . . . it's no doubt in the archives. You really should not "embellish" your qualifications. Engineers go to school and learn math, physics, science and an intensive engineering curriculum. I'm offended you'd even think you are an "engineer". It's just dishonest. I have never claimed to be anything more than what my resume' states nor what my employers were willing to compensate me for performing. Since they paid me well for my performance as an engineer in the company of other engineers, you'll please forgive me if I defer to their definition of the task as opposed to the opinion of one who pays me nothing, designs nothing, has offered no well considered teachings nor satisfies any customer base. I humbly suggest that while you claim be an engineer on paper, I'm an engineer in the marketplace of customers. Your studies may have ended years ago but mine have been ongoing since childhood. I am (as should we all be) a life-long students/teachers in the college of "make it work". You are not a Doctor, Lawyer or Indian Chief either. Is that battery test circuit your original design? Say what? It's a computer driven data acquisition module set up to plot voltage over time. If one uses a tape measure to gather statistical data on the variation in lengths on pre-cut studs, is one obligated to tip their hat to who ever perfected the roll-up steel tape? Here is another link with extensive comparisons of brands of alkaline batteries. http://www.candlepowerforums.com/vb/showthread.php?t=64660 Nice work . . . much of the data meshes with the study I did. The article offers some interesting findings on absolute performance. The study I conducted went to a deduction of $value$ for the various products. The idea was to meet design goals for minimizing cost of a single mission while maximizing reliability of the battery powered device by not fiddling with loose cells and battery box covers in the cockpit. Personally I am sold on NiMh for all my applications. People complain they don't last as long. I suspect they don't have the latest NiMh technology, . . . . . . receiver. I do keep some Alkaline's around for "emergencies". However with all the NiMh fully charged I really don't need them. An interesting design goal . . . but doesn't seem to address the topic of this thread. Are you starting a new thread? If you want to talk NiMh, I've personally tossed out never-used cells from inventory that already showed signs of leakage . . . Merry Christmas every one, fly safe! George, you wade in kicking up a cloud of chicken feathers and pigeon poop and then wish folks a merry Christmas . . . at best disingenuous and at worst hypocritical to the extreme. Bob Nuckolls, EPT (Engineer in perpetual training) ________________________________________________________________________________
Date: Dec 26, 2009
From: Bill Mauledriver Watson <MauleDriver(at)nc.rr.com>
Subject: Re: Was Ammeter Help- Now about switches
I like the AML 34 switches and AML 41 indicators too. Here's my Z-14 design and specs. John Burnaby wrote: > Bob, > Now you've got me thinking Z-14. If I go with another alternator, I'm > one contactor away from Z-14. > > One thing that is vexing to me is that I'm using Honeywell AML 34 > switches because the aesthetics appeal to me. Problem is that they are > only available as DPST. I haven't thought about this too much, but I'm > assuming that I can accomplish the switching functions shown in Z-14 > and other architectures with the Honeywell switches, but I'll just > have to use more of them and some behind-the-panel circuitry??? I can > see the S-700-2-5 being replaced with an AML 34 and a pusbutton > switch. But what combination would I use to achieve the function of > S-700-2-10? In other architectures I see this switch associated with > some automatic function that I don't understand. > * > > > * ________________________________________________________________________________
Date: Dec 26, 2009
From: Bill Mauledriver Watson <MauleDriver(at)nc.rr.com>
Subject: Re: Was Ammeter Help- Now about switches
I was looking at the Z-14 diagram and see that I used a standard key switch for the starter and mag switching in place of the S-700-2-5 (in 5/9/06 revision it is an S-700-2-7). A pic of my panel can be found here: http://www.vansairforce.com/community/showthread.php?t=18921&page=13 Have fun with the electrical design. Everything you need is here in Bob's world. Quite a resource. Bill "making fiberglass dust" Watson RV10 Durham NC Bill Mauledriver Watson wrote: > I like the AML 34 switches and AML 41 indicators too. Here's my Z-14 > design and specs. > > > John Burnaby wrote: >> Bob, >> Now you've got me thinking Z-14. If I go with another alternator, I'm >> one contactor away from Z-14. >> >> One thing that is vexing to me is that I'm using Honeywell AML 34 >> switches because the aesthetics appeal to me. Problem is that they >> are only available as DPST. I haven't thought about this too much, >> but I'm assuming that I can accomplish the switching functions shown >> in Z-14 and other architectures with the Honeywell switches, but >> I'll just have to use more of them and some behind-the-panel >> circuitry??? I can see the S-700-2-5 being replaced with an AML 34 >> and a pusbutton switch. But what combination would I use to achieve >> the function of S-700-2-10? In other architectures I see this switch >> associated with some automatic function that I don't understand. >> * >> ________________________________________________________________________________
Subject: Re: duracell battery leak
From: "rvtach" <rvtach(at)msn.com>
Date: Dec 26, 2009
Sometimes you get what you pay for. Sometimes it doesn't matter. But it's crazy what people try to save money on (airplane tickets, health insurance, car tires). When we buy the cheapest option available we force the higher quality providers of whatever product or service to compete with that option and so all the options available in the marketplace start to look a lot like the cheap stuff. If enough of us are buying our batteries at Harbor Freight then it's safe to assume that Duracell will start making batteries that compete with the Chinese produced stuff rather than making the best batteries they know how to make. -------- Jim McChesney Tucson, AZ RV-7A Finishing Kit Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278894#278894 ________________________________________________________________________________
Subject: dynon fuel pressure sensor location on 912s
From: "Tucsonchris" <gallchrisa(at)qwest.net>
Date: Dec 26, 2009
Does anyone have a good description, or better yet, a picture of exactly where this sensor is supposed to be installed in the 912s fuel distribution junction? Will I need a fuel restrictor as well? Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278895#278895 ________________________________________________________________________________
Subject: Re: Was Ammeter Help- Now about switches
From: "user9253" <fran4sew(at)banyanol.com>
Date: Dec 26, 2009
Some aircraft use a DPST switch to control the master contactor and the alternator field instead of DPDT. Wired like this, both the master contactor and the alternator must be turned on or turned off together. The alternator can not be off while the master contactor is on. Is there any disadvantage of wiring it this way? Many TC aircraft have split master switches so that the pilot can shut off the alternator without shutting off the master contactor. Many pilots do not understand why the master switch is split and would not know under what circumstances they should shut off the right hand side of the switch. Has anyone ever had reason to disable the alternator in flight? If the aircraft is wired according to one of Bob N's drawings that incorporate an essential bus circuit and automatic over-voltage protection, then there is no need to have separate control over the alternator. In case of high voltage, the alternator is automatically disabled. In case of low voltage, the pilot can turn on the essential-bus switch and shut off the master switch. In fact, why even have an alternator field switch? The alternator field could be connected directly to the main power bus (through a circuit breaker). I suspect that more incidents have occurred when the pilot inadvertently left the alternator shut off, then when a problem arose requiring the alternator to be disabled. Is it better to give the pilot separate control over the alternator or is it better to keep it simple to reduce operator error? Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278896#278896 ________________________________________________________________________________
Date: Dec 26, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: duracell battery leak
>If enough of us are buying our batteries at Harbor Freight then it's >safe to assume that Duracell will start making batteries that >compete with the Chinese produced stuff rather than making the best >batteries they know how to make. That poses a bit of a chicken/egg conundrum. Would you suppose that houses like Duracell sought out less expensive processes in order to compete with the Harbor Freight guys? Were that so, would it not follow that their ability to 'compete' would be annunciated by a reduction in prices? I've observed no changes in Duracell's market presence that would suggest they are feeling any pressure from H.F. or anyone else. It seems more likely that they have farmed out manufacturing duties to lower-cost houses in a move generally calculated to improve bottom line with the present market philosophy. It's quite common that manufacturers of many goods from washing machines to toasters and even flashlight cells will brand their output to the wishes of any customer. In the 'Connection I wrote about an alternator reman operation in Mexico that produced the identical part for sale under many brands and offered at several tiers of "quality" level. I'd rather imagine that alkaline cells are no different. The risk for sad outcomes is easy to imagine . . . especially when the collective pipelines are so very demanding of product flow. Suppose you have a marketing pipeline that MUST be filled 24/7/365 with boat-loads of alkaline cells. Suppose further that some manufacturing house you've partnered with has stubbed their toe. What period of time might elapse from the point that pressures of quality issues become so great that you seek alternative sources? And once demands for such a pipeline are being met, it seems that locating and switching to another source capable of meeting your product flow demands is not a simple task. Watch episodes of "Unwrapped". Put aside any attention to the product being showcased and consider the investment of time, talent and resources to craft a product, build a facility to manufacture including mind-boggling machines that churn out tons of product per day. All those products must be distributed to outlets already committed to purchase based on your marketing efforts. Then imagine the chaos that would ensue should a large manufacture of product for dozens of items and perhaps as many different brands stubs it's toe on a quality issue. If we were talking about Harbor Freight cells, no doubt the consensus would be, "Well, you get what you pay for." One automatically downgrades expectations of the low-cost brands. But suppose the same house is making both H.F. and Duracells . . . among many others. The fact that you paid for a whippy looking label, $millions$ in television and print advertising, and faith in a "quality brand" becomes more significant . . . even though the same factory made both products. That's why those oft maligned CEO's of honorable companies make so much money. They are supposed to be quite talented in the herding of cats while being good stewards of many $millions$ in investor funds and turning in a 6 to 10% profit year after year. Our collective observations about Duracells does not bode well for the folks responsible for herding the company's cats . . . nor for the folks who bought the cat food. It doesn't take a very big problem to seriously erode an otherwise consistent profit that made your stock so attractive LAST year. Bob . . . ________________________________________________________________________________
Date: Dec 26, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Was Ammeter Help- Now about switches
At 10:30 AM 12/26/2009, you wrote: > >Some aircraft use a DPST switch to control the master contactor and >the alternator field instead of DPDT. Wired like this, both the >master contactor and the alternator must be turned on or turned off >together. The alternator can not be off while the master contactor >is on. Is there any disadvantage of wiring it this way? No, in fact early Z-figures proposed just that . . . before fuse-blocks came along. In those days, existence of a pullable circuit breaker made it possible to shut off the field circuit for extended battery only ground operations. > Many TC aircraft have split master switches so that the pilot can > shut off the alternator without shutting off the master > contactor. Many pilots do not understand why the master switch is > split and would not know under what circumstances they should shut > off the right hand side of the switch. Has anyone ever had reason > to disable the alternator in flight? Not necessarily in flight. More often one wants to operate battery-on while leaving the alternator field off as cited above. Using a simpler DPDT DC PWR MASTER combined with the pullable circuit breaker works too. > If the aircraft is wired according to one of Bob N's drawings > that incorporate an essential bus circuit and automatic > over-voltage protection, then there is no need to have separate > control over the alternator. In case of high voltage, the > alternator is automatically disabled. In case of low voltage, the > pilot can turn on the essential-bus switch and shut off the master > switch. In fact, why even have an alternator field switch? The > alternator field could be connected directly to the main power bus > (through a circuit breaker). I suspect that more incidents have > occurred when the pilot inadvertently left the alternator shut off, > then when a problem arose requiring the alternator to be > disabled. Is it better to give the pilot separate control over the > alternator or is it better to keep it simple to reduce operator error? The design goals for pilot control for all sources of electrical energy have been with us for a very long time. Whether or not you choose to embrace and implement them is a personal choice enjoyed by the OBAM aircraft community. Bob . . . ________________________________________________________________________________
From: "Tim Andres" <tim2542(at)sbcglobal.net>
Subject: Switches
Date: Dec 26, 2009
I'm looking for a nice switch to use in a speed brake/landing gear control panel I want to make. I could of course just use toggle switches but I wanted something little nicer. I found these rotary lever switches https://www.mouser.com/catalog/640/2375.PDF from electro switch, there very nice, smooth and just what I want but they don't have the rating I need (10 amps). I'm trying to avoid using a relay. I'm open to suggestions; I have been all over the internet without any luck. Thanks, Tim Andres ________________________________________________________________________________
Date: Dec 26, 2009
From: jerb <ulflyer(at)verizon.net>
Subject: Re: "engineers"
Since this decay and collapse is so wide spread could it be attributed to the quality of water we consume today. jerb At 08:30 AM 12/25/2009, you wrote: > > >There has been a general and profound decay and collapse of leadership >throughout the United States over the past few decades. Compare the 1960s >(when I was growing up) to now. Then: Man on the moon in 8 years; Now: >years to produce a rocket that doesn't do more than the Saturn 5. Then: >Build the world's best university and freeway system in California; Now: sit >around arguing as those same systems decay into mediocrity. Then: exercise >fiscal prudence in banking to supply credit for business progress; Now: >exercise wild and greedy schemes to ruin the world economy. Then: Start a >stupid war half way around the world for nothing. Now: oh, wait, some >things remain the same. > >This is, of course, far beyond engineers. I don't see any permanent >improvement happening to our leadership either, most everybody has become >hooked on stupid pills. That leaves it to individuals, as Bob N. put. > >And why not? That's where we started nearly 400 years ago, individuals >banding together and bettering their own lot. > >In my professional life I'm a water resources engineer doing numerical >modeling for a large state agency. Leadership has declined over the last 20 >years to where it's impossible to get anything quality done through >management. But instead of waiting for them to realize what the problems are >and providing support, we are moving ahead with crowd-sourcing to check >data, review source code, etc. This email list and other forums are a form >of the same thing: individuals getting together on our own to improve things >for everybody. The need is the same, just the technology different from the >Pilgrims. > >Ralph Finch >Davis, California >RV-9A QB SA > > >__________ Information from ESET Smart Security, version of virus signature >database 4716 (20091225) __________ > >The message was checked by ESET Smart Security. > > ________________________________________________________________________________
Subject: Re: Was Ammeter Help- Now about switches
From: "jonlaury" <jonlaury(at)impulse.net>
Date: Dec 26, 2009
Bill Bob and Joe, Thanks for your comments and schematics. Bill's Z-14 is exactly how I plan to put Z-14 to use. Where Bob uses a 700-2-7, theres a pin connected to the volt meter and I don't get what this circuit is about. From somebody's post, I picked up that this circuit had an auto switch function in the event of OV. Can either of you clarify this? Thanks, John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278918#278918 ________________________________________________________________________________
From: "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net>
Subject: Re: Was Ammeter Help- Now about switches
Date: Dec 27, 2009
Where Bob uses a 700-2-7, theres a pin connected to the volt meter and I don't get what this circuit is about. From somebody's post, I picked up that this circuit had an auto switch function in the event of OV. Can either of you clarify this? Thanks, John I am not sure about your reference to a connection to a voltmeter, but Bob's Z-14 drawing has the S700-2-7 switch labeled as STARTER/CROSS-FEED. There is a light to the left of the switch which will illuminate whenever the cross-feed contactor is activated. This light will illuminate when the switch is pushed up, to activate the starter, simultaneously activating the cross-feed contactor, so you use both batteries for starting. When the switch is pushed down, it will activate the cross-feed only, tying the two batteries together, but not activating the starter. Hope this is the info you were looking for. Roger ________________________________________________________________________________
Subject: Re: Switches
From: "racerjerry" <gki(at)suffolk.lib.ny.us>
Date: Dec 27, 2009
Nice switches are for non-critical applications far away from airplanes. If you value reliability and/or your life, pick a snap action switch with proper rating that has been tested and qualified with a MS (Military Specification) number attached to it. -------- Jerry King Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278927#278927 ________________________________________________________________________________
Subject: Re: "engineers"
From: "Eric M. Jones" <emjones(at)charter.net>
Date: Dec 27, 2009
I completely agree in spirit with Bob and Ralph (BTW Ralph...wasn't it Germans who designed the Saturn V?). But the history of the US (and the World) was always like this. Read Anti-Intellectualism in American Life by Richard Hofstadter. America is a complicated place. The European Age of Enlightenment spawned our Founding Fathers whose clear vision created our land. While the anti-intellectuals and religious zealots were being thrown out of Europe and arrived on, for example, the Mayflower. Early history says that Massachusetts produced Yankee craftsmen and engineers who LEFT to spread out over the country. NYC produced financiers and business people who STAYED. This says a lot. America became the destination for all the teeming anti-intellectuals of those foreign shores. This is distrust of Intellectuals is hardly unique. The first thing any tyrant or dictator knows is to line up the intellectuals and engineers against the wall and shoot them. But I am not so displeased as many. Years ago I read an opinion piece in Design News (or such) from a guy who earned college spending money by buying old cars, fixing them up and selling them. His roommate, on the other hand, bought and sold cars but HIRED other people to do the wrench turning. His roommate made all the money. So who do you think added more value to the worldBob and Ralph and designers and engineers, or the owners of Beechcraft who wouldnt know one end of a soldering iron from the other? Everybody plays a part in the great carnival. -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones(at)charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278932#278932 ________________________________________________________________________________
Date: Dec 27, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Switches
At 09:24 AM 12/27/2009, you wrote: > >"Nice" switches are for non-critical applications far away from >airplanes. If you value reliability and/or your life, pick a snap >action switch with proper rating that has been tested and qualified >with a MS (Military Specification) number attached to. Perceived reliability of individual parts does not directly contribute to reliability of whole systems. As I explained in chapter 17, one may craft very reliable systems from components that are not selected just for their exemplary service life. Super-parts are not offered as "failure free" . . . just longer service life between failures. System reliability is a byproduct of crafting alternatives for the failure of any system useful for comfortable termination of flight. This is an important concept that accounts for the failure of any system component, poor craftsmanship, accident, etc. In other words, the sources for in-flight misery go far beyond the selection of specific components. The failure tolerant flight system can suffer from an extra-ordinary frequency of events that drive up maintenance time and expense . . . without degrading reliability. Here I'll suggest that system reliability is judged by one's ability to suffer the failure of any component and proceed to original airport of intended destination without breaking a sweat. I'm not suggesting that "super-parts" should not be considered. I do suggest that placing one's faith in their ability to ward off sweaty cockpits is misplaced. All the super-testing in the world does nothing for you when the landing light burns out, the terminal breaks or the radio decides to quit (as all radios eventually do). Failure tolerance flows out of an analysis of failure mode effects for equipment YOU have installed for use in the environment YOU intend to fly and is dependent upon YOUR understanding of system functionality. Remember that decades of dark-n-stormy night stories have demonstrated the inadequacy of 'certified' aviation products operated by pilots who were lead to believe that getting their ticket from an approved school was the golden shield against sweaty experiences in the cockpit. Those of us who buck rivets, turn wrenches and string wires in the garage have already accepted the need for extra ordinary skill and knowledge. Shopping for the Mil-Spec part doesn't cut it. Bob . . . ________________________________________________________________________________
Date: Dec 27, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Switches
At 04:25 PM 12/26/2009, you wrote: >I'm looking for a nice switch to use in a speed brake/landing gear >control panel I want to make. I could of course just use toggle >switches but I wanted something little nicer. I found these rotary >lever switches >https://www.mouser.com/catalog/640/2375.PDF >from electro switch, there very nice, smooth and just what I want >but they don't have the rating I need (10 amps). I'm trying to avoid >using a relay. I'm open to suggestions; I have been all over the >internet without any luck. >Thanks, Tim Andres These are open frame, wafer switches fitted with long throw handles as opposed to rotary shafts. These switches have been around for decades and are widely used in communications. Their open construction makes them unattractive for harsh industrial or aviation environments. In the TC aircraft world, this style of switch has been considered and rejected many times. Consider emulating the approach taken by Beech and others illustrated here: http://aeroelectric.com/Pictures/Switches/FLAPS3.JPG http://aeroelectric.com/Pictures/Switches/FLAPS2.JPG http://aeroelectric.com/Pictures/Switches/FLAPS1.JPG Bob . . . --------------------------------------- ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) --------------------------------------- ________________________________________________________________________________
Date: Dec 27, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: About switches
At 12:36 AM 12/27/2009, you wrote: > >Bill Bob and Joe, > >Thanks for your comments and schematics. Bill's Z-14 is exactly how >I plan to put Z-14 to use. > >Where Bob uses a 700-2-7, theres a pin connected to the volt meter >and I don't get what this circuit is about. From somebody's post, I >picked up that this circuit had an auto switch function in the event of OV. >Can either of you clarify this? Where do you see a 2-7 connected with a voltmeter? I've just checked the Figure Z-14 as currently published and found an error. The starter-crossfeed switch properly drawn as a DP3P ON-OFF-(ON) device spring loaded out of only ONE of the extreme positions - starting. The other extreme is a held position that allows a continuous operation of the crossfeed contactor. A 2-7 is spring loaded out of both extremes . . . the proper switch call-out is a 2-5. See figure 11-14 in the 'Connection. I'll correct Z-14 when I get back to the office. In the mean time, I'm not connecting with any call outs for a 2-7 associated with a voltmeter. Bob . . . --------------------------------------- ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) --------------------------------------- ________________________________________________________________________________
Date: Dec 27, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Battery Equalizers
At 12:36 AM 12/17/2009, you wrote: >Bob, >The planned use for the battery equalizer is to allow the charge >state of the two batteries in a 24V system to equalize after one >battery is used (via the center tap) to run the 12V hydraulic >pump. My thought is that the battery will easily supply the 20A >load for 30 seconds or so to required to raise the gear, after which >the equalizer will act to direct energy to it in order to bring its >charge state up to equal that of the other battery. The particular >unit I've chosen is called PowerCheq and appears to be designed for >just such an application. It's produced by a company called Power >Designers, here's a link to the manual for the unit: > ><http://www.evsource.com/datasheets/powercheq/powercheq_operations_manual.pdf>http://www.evsource.com/datasheets/powercheq/powercheq_operations_manual.pdf > >and here's a link to a white paper on its design and testing: > ><http://www.fleetcareequipment.com/files/phatfile/PowerCheqPaper_MotivePower.pdf>http://www.fleetcareequipment.com/files/phatfile/PowerCheqPaper_MotivePower.pdf > >I'm not a Double-E, so I welcome comment from you and others out >there regarding the usefulness of such a beast. Dan, I've been pondering your request. I'm having trouble wrapping my head around a design task that increases weight, complexity and cost of ownership to side-step an ordinary procurement task to swap 14v equipment out in favor of 28v equipment. I suspect there are few if any folk who have implemented the equalized split battery architecture to achieve a quasi-dual voltage system. My only experience with a tapped battery scheme involved a pusher design that needed electric augmentation of cooling on the ground. The builder ran a pair of 14v fans off the top battery . . . another pair on the bottom battery. Unfortunately, the airplane crashed before the wisdom of the experimental architecture could be evaluated. You're a the leading edge of the investigation for what you've proposed. Were it my airplane, I would swap the parts out and stay with an all 28v system. Bob . . . ________________________________________________________________________________
Subject: Re: Was Ammeter Help- Now about switches
From: "jonlaury" <jonlaury(at)impulse.net>
Date: Dec 27, 2009
All, I got Z-14 and 19 confused. The circuit that I don't understand is in Z-19. It's the ENG BAT, OFF/ON/Auto circuit using a 700-2-10 switch. When switched to the 3rd position, contacting pin 4, what happens? Pin 4 goes to the 'Relay' pin of the LoVo monitor. John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278944#278944 ________________________________________________________________________________
Date: Dec 27, 2009
From: James Robinson <jbr79r(at)yahoo.com>
Subject: Battery charging
I posted a question awhile back in regard to charging 2 batteries at the same time. I didn't understand the answer so the question must not have been properly worded. I have a 2 battery (same size)system and I want to charge both batteries at the same time with my "battery Tender Charger" The negatives are already both connected to ground . can I connect the positive terminals together to the positive of the Battery Tender, thus charging both at the same time. I don't understand why there would be a problem, But??? Jim James Robinson Glasair lll N79R Spanish Fork UT U77 ________________________________________________________________________________
Date: Dec 27, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Battery charging
At 02:40 PM 12/27/2009, you wrote: >I posted a question awhile back in regard to charging 2 batteries at >the same time. I didn't understand the answer so the question must >not have been properly worded. I have a 2 battery (same size)system >and I want to charge both batteries at the same time with my >"battery Tender Charger" The negatives are already both connected >to ground . can I connect the positive terminals together to the >positive of the Battery Tender, thus charging both at the same >time. I don't understand why there would be a problem, But??? Sorry Jim . . . the article I referenced was intended to show that batteries of any size and condition can be charged and/or discharged in parallel. Each battery will accept and hold what ever energy it's chemistry condition will allow. Each battery will deliver what ever energy it contains even if a small fraction of its paralleled brothers. Except for what is now an exceedingly rare shorted cell (12v battery becomes 10v battery) two paralleled batteries do no exchange significant quantities of energy. The short answer is, yes. Just parallel those puppies and hook up the Battery Tender. I've had as many of four lead-acid batteries being shepherded by one maintainer with great success. Bob . . . ________________________________________________________________________________
Date: Dec 27, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Was Ammeter Help- Now about switches
At 01:35 PM 12/27/2009, you wrote: > >All, > >I got Z-14 and 19 confused. > >The circuit that I don't understand is in Z-19. It's the ENG BAT, >OFF/ON/Auto circuit using a 700-2-10 switch. When switched to the >3rd position, contacting pin 4, what happens? Pin 4 goes to the >'Relay' pin of the LoVo monitor. Okay. THAT drawing shows the AEC9005 Aux Battery Management/LV Warning module . . . http://www.aeroelectric.com/Catalog/AEC/9005/LV_Warn_Fab_and_Install.pdf The 3-position Aux Battery switch in question offers an OFF function at full down, a manual ON function at the mid position and an AUTOMATIC management function at the full up position. This functionality is described in the document cited above. The 9005 is being replaced by versions of the 9024 reviewed at . . . http://www.aeroelectric.com/Catalog/AEC/9024/ with applications illustrated at . . . http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z09A.pdf Bob . . . ________________________________________________________________________________
Date: Dec 27, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Switches
>The circuit that I don't understand is in Z-19. It's the ENG BAT, >OFF/ON/Auto circuit using a 700-2-10 switch. When switched to the >3rd position, contacting pin 4, what happens? Pin 4 goes to the >'Relay' pin of the LoVo monitor. Okay. THAT drawing shows the AEC9005 Aux Battery Management/LV Warning module . . . http://www.aeroelectric.com/Catalog/AEC/9005/LV_Warn_Fab_and_Install.pdf The 3-position Aux Battery switch in question offers an OFF function at full down, a manual ON function at the mid position and an AUTOMATIC management function at the full up position. This functionality is described in the document cited above. The 9005 is being replaced by versions of the 9024 reviewed at . . . http://www.aeroelectric.com/Catalog/AEC/9024/ with applications illustrated at . . . http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z09A.pdf P.S. Figure Z-09 for the Corvair engine only illustrates three of the four features offered by the 9024. The fourth function just happens to be the Aux Battery Management Module. Nonetheless, there are 4 possible functions for this product. Bob . . . ________________________________________________________________________________
Date: Dec 27, 2009
Subject: Re: duracell battery leak
From: bob noffs <icubob(at)gmail.com>
jim, if that was the case then duracell is trying to increase their profits as i dont see them competing with prices bob noffs On Sat, Dec 26, 2009 at 9:21 AM, rvtach wrote: > > Sometimes you get what you pay for. Sometimes it doesn't matter. But it's > crazy what people try to save money on (airplane tickets, health insurance, > car tires). When we buy the cheapest option available we force the higher > quality providers of whatever product or service to compete with that option > and so all the options available in the marketplace start to look a lot like > the cheap stuff. If enough of us are buying our batteries at Harbor Freight > then it's safe to assume that Duracell will start making batteries that > compete with the Chinese produced stuff rather than making the best > batteries they know how to make. > > -------- > Jim McChesney > Tucson, AZ > RV-7A Finishing Kit > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=278894#278894 > > ________________________________________________________________________________
From: "Tim Andres" <tim2542(at)sbcglobal.net>
Subject: Switches
Date: Dec 27, 2009
Thanks Bob; I guess I knew but forgot the points you made, should have known better. I see what I want around but it's made for heavy iron and cost like it also. Tim ________________________________________ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Sunday, December 27, 2009 8:46 AM Subject: Re: AeroElectric-List: Switches At 04:25 PM 12/26/2009, you wrote: Im looking for a nice switch to use in a speed brake/landing gear control panel I want to make. I could of course just use toggle switches but I wanted something little nicer. I found these rotary lever switches https://www.mouser.com/catalog/640/2375.PDF from electro switch, there very nice, smooth and just what I want but they dont have the rating I need (10 amps). Im trying to avoid using a relay. Im open to suggestions; I have been all over the internet without any luck. Thanks, Tim Andres These are open frame, wafer switches fitted with long throw handles as opposed to rotary shafts. These switches have been around for decades and are widely used in communications. Their open construction makes them unattractive for harsh industrial or aviation environments. In the TC aircraft world, this style of switch has been considered and rejected many times. Consider emulating the approach taken by Beech and others illustrated here: http://aeroelectric.com/Pictures/Switches/FLAPS3.JPG http://aeroelectric.com/Pictures/Switches/FLAPS2.JPG http://aeroelectric.com/Pictures/Switches/FLAPS1.JPG Bob . . . --------------------------------------- ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) --------------------------------------- ________________________________________________________________________________
Subject: Re: Switches
From: "racerjerry" <gki(at)suffolk.lib.ny.us>
Date: Dec 27, 2009
OK! Shot down by the master I respect Bobs arguments; however, I do not consider a $20 Mil-Spec switch to be a super-part. Certainly we can use commercial grade switches in our homebuilt aircraft, but it is still prudent to insure that the switches have undergone some reliability testing and have current and voltage ratings appropriate for their intended use. Certification by a nationally recognized testing agency such as Underwriters Laboratories may add to the switches cost a bit, but the rating confirms that required overload and endurance testing have been successfully completed. The lever actuated open frame rotary type switch that Tim proposed to use was almost a guaranteed failure point. Besides susceptibility to contamination of the open switch contacts by dirt and dust, arc characteristics of direct current require a switch that rapidly breaks the circuit in order to prevent excessive arcing damage to the switch contacts; most especially when 10 ampere loads are contemplated. A snap-action type switch has much greater survivability chances under heavy DC loads. I see that Bob has suggested a possible alternative, a bolt on extension to the switch bat handle. Keep in mind that Bobs addition ENHANCES safety. This extension allows the pilot to quickly and positively locate the flap switch by feel without the necessity of removing eyes from the windshield; kinda important when you are close to the ground. If you are tempted to add such extensions willy-nilly just because they look pretty, keep in mind that these extensions can possibly do a lot of damage during a survivable crash when body parts are violently thrown about to the limits of the restraint system (and then some). Everything has its price, including cutesy. -------- Jerry King Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278962#278962 ________________________________________________________________________________
Subject: Re: Was Ammeter Help- Now about switches
From: "jonlaury" <jonlaury(at)impulse.net>
Date: Dec 27, 2009
Thank you Bob. I got it now. Sorry for the confusion. John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=278970#278970 ________________________________________________________________________________
Date: Dec 27, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: "engineers"
At 10:35 AM 12/27/2009, you wrote: I completely agree in spirit with Bob and Ralph . . . But I am not so displeased as many. Years ago I read an opinion piece in Design News (or such) from a guy who earned college spending money by buying old cars, fixing them up and selling them. His roommate, on the other hand, bought and sold cars but HIRED other people to do the wrench turning. His roommate made all the money. So who do you think added more value to the world? Bob and Ralph and designers and engineers, or the owners of Beechcraft who wouldn't know one end of a soldering iron from the other? I think we're talking about different things. A robust free-market in a civilized society NEEDS organizers . . . these individuals can perceive cause/effect/opportunity over a broad range of disciplines. They may not be expertly talented in many of them but they have an understanding as to where they all fit into the larger picture . . . and how to select the best practitioners of those talents to fill a niche in the grand scheme. Our teachers like Lear, Wallace, Gates, Johnson, Edison, Ford, Kettering, et. als. come to mind in this regard. These folks were/are absolutely dependent upon those who fill a host of niches . . . they sought out the best of their lot. The important difference between the successful grand scheme and the unsuccessful grand flop is how all ingredients are combined in the crafting of recipes for success. Many of the "grunts" that worked with and for them could not begin to do what the boss does . . . but the boss couldn't do what THEY did either . . . Judgement as to who adds the most value to any endeavor (or the world at large) based on their personal cash-flows is irrelevant. It ignores the fact that while a skill-set has market value based on supply, demand and contribution . . . in the successful grand scheme, all skills at all levels must be artfully selected and nurtured. I recall a story in a trade journal about out-sourcing problems with the B-787. The author was noting how a shortage of a few relatively inexpensive parts could bring a $billion$ production line to a halt. Similarly, I'd bet that each of Kelly Johnson's staff from janitor to program managers at the Skunk Works were all selected for excellence at their respective skills along with their willingness and ability to move the project forward. Loss of any one of THEM would have presented the organizers with an important problem to resolve. My disparaging remarks about the state of engineering departments are necessarily limited to what I've observed as a both an employee and a provider of goods and services various factions of the aviation community. I've witnessed pitiful waste of potential talent in activities all striving for successful status in the constellation of grand schemes, but a few stellar exceptions come to mind. One in particular: http://tinyurl.com/ya63jgj The first time I saw this airplane I was consulting for a potential supplier of flap extension systems. The prototype was well along and had an engine hung on it. The entire operation probably didn't total 20 people. All wore lots of hats. In a little metal building on a small, remote airport, a few folks were practicing their art with great skill. BSME, PhDEE? MBA? MSAE? Did they learn their skill in the shadows of master craftsmen? Haven't a clue . . . While sitting around their conference table, reading their specifications, looking at the craftsmanship on the shop floor . . . it didn't occur to me to even wonder if they were in possession of proper 'credentials'. Their qualifications for the task were self-evident. When we delivered a flap system that functioned as advertised some months later, I hope our qualifications for the task were equally self- evident. Bottom line is that the value of work-product over time is the ultimate gage by which competency can be judged. A dozen diplomas are of little value if the holder cannot demonstrate competency in meeting customer requirements. Further, a high degree of competency as either manager, organizer, designer, builder or janitor may have little connection with what that individual learned in school. I hope it's clear that I have no animosity for engineers degreed or otherwise. I am saddened and often angered by what I perceive as incompetent, technically ignorant, policy and procedure driven management that squanders potentially valuable human resources while wondering in amazement why their stature in the marketplace is slipping. I believe the ghosts of our teachers who walk the isles and stalk the conference rooms are more saddened than I . . . Bob . . . ________________________________________________________________________________
Date: Dec 27, 2009
Subject: Re: "engineers"
From: "Ralph&Maria Finch" <ralphmariafinch(at)gmail.com>
Now let's update this anecdote for 21st century America. The roommate buys old cars and hires the cheapest labor he can find, undocumented immigrants, to fix the cars. He pays them below minimum wage and collects taxes which he never reports, threatening the workers to turn them into ICE if they complain. He applies for and receives government bailout money while also taking in venture capital to take his company public. Administrative tasks are outsourced to India, and his parts come from Chinese knockoff firms. Once he goes public with an IPO he cashes out, along with the VCs, and leaves the company $3 Billion richer. A year the company goes bankrupt because of vague rumors of federal investigations. OK, this is not the correct venue to discuss this sort of thing. I'm the biggest complainer of abuse of this email list and now I'm guilty. Please don't reply to the list about this thread...if you want to continue we'll find another venue. RF On Sun, Dec 27, 2009 at 6:36 PM, Robert L. Nuckolls, III < nuckolls.bob(at)aeroelectric.com> wrote: > But I am not so displeased as many. Years ago I read an opinion piece in > Design News (or such) from a guy who earned college spending money by buying > old cars, fixing them up and selling them. His roommate, on the other hand, > bought and sold cars but HIRED other people to do the wrench turning. His > roommate made all the money. > ________________________________________________________________________________
From: "Keith Burris" <klburris(at)frontiernet.net>
Subject: Good website
Date: Dec 28, 2009
Folks; Many of you probably know about these places but some may not. I found the prices to be reasonable. http://www.wiringproducts.com/index.html Also, this place has some interesting products, especially for RVers. The guy who runs it, Rich, is quite easy to work with http://aircraftextras.com/ -- Keith ________________________________________________________________________________
From: "Jared Yates" <junk(at)jaredyates.com>
Subject: Tube and Fabric Ground Plane
Date: Dec 28, 2009
Dear group, I'm building a Bearhawk and would like to find the best way to mount the ELT antenna, especially regarding the ground plane. I'm using the Ameriking 450 and the whip antenna that came with it. I can use the aluminum wing as a ground plane for the VHF com, but I was thinking that it would be better to keep the ELT antenna on the fuselage. This would allow me to reduce the length of the wire run and thus reduce the chances of crash damage. It would also allow me to provide enough distance between the com and ELT to prevent resonance on the emergency frequency. Some builders have mounted the antenna inside of the 4130 tube fuselage, which has the best crash resistance; but, I would think that the fuselage would be a great faraday cage and would thus limit the transmission considerably. For these reasons I'd prefer to mount the antenna on the top of the fuselage behind the cabin. In this particular fuselage there are non-structural stringers that protrude about 3 inches above the primary structure, so I was planning to make a bracket to use as a mount for the antenna. The bracket would be shaped like an upside down U with the top of the bracket even with the top of the stringers, so that the antenna would attach at the top of the bracket and the bottom legs would be welded to either side of a crossing tube. How should I provide for a ground plane? The stringers are aluminum and about 12 inches apart, and the steel fuselage is about 3" below the base of the antenna. Would it be a good idea to use either of those as part or all of the ground plane, or would it be better to make something out of copper foil and try to insulate that ground plane from the airframe parts? Any thoughts? Here's a picture of how the fuselage is built: http://jaredyates.com/temp/groundplane.jpg Thanks ________________________________________________________________________________
Date: Dec 28, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Switches
At 06:01 PM 12/27/2009, you wrote: > >Thanks Bob; I guess I knew but forgot the points you made, should have known >better. I see what I want around but it's made for heavy iron and cost like >it also. Yeah. I've participated in the design of a number of specialized cockpit controls for things like gear, flaps, spoilers, etc. In addition to their unique form and fit requirements to comply with design goals for cockpit decorum, they often included a variety of position sensors with redundancy to preclude un-commanded motions, etc. I think the last flap control handle project I saw produced a device that sold to the OEM for about $2,000! Here in the OBAM aircraft world, we can do a lot to dress up plain vanilla controls. But the Big Guys do it too. The gear and flap switches in a Bonanza are Honeywell toggle switches with added window dressing. Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ ________________________________________________________________________________
Date: Dec 28, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Switches
At 06:57 PM 12/27/2009, you wrote: OK! Shot down by the master! I respect Bob's arguments; however, I do not consider a $20 Mil-Spec switch to be a super-part. Certainly we can use commercial grade switches in our homebuilt aircraft, but it is still prudent to insure that the switches have undergone some reliability testing and have current and voltage ratings appropriate for their intended use. Certification by a nationally recognized testing agency such as Underwriters Laboratories may add to the switches cost a bit, but the rating confirms that required overload and endurance testing have been successfully completed. Are we shooting at each other or trying to achieve a shared understanding? How does one conduct such pre-purchase studies? I'm fairly certain that every manufacturer did some pre-production proof of design testing to insure compliance with their own design goals. But few if any have published reports on such studies unless they're attempting to compete with other manufacturers where the rules of the game call out Mil-Spec, SAE, ISO, UL, etc. etc. I'll suggest that there are many sources of switches suited to our tasks that offer no published test data. Further, when data is available, it was not gathered by the same test protocols as competing products. I went through this exercise 20+ years ago on the GP-180 program at Gates-Learjet. Attempts to evaluate 6 different brands of interchangeable basic switches based on their published data proved impossible. But in fact, every device being considered would have been just fine for our application. I would invite you to review a paper I wrote some years ago about switch ratings at: http://www.aeroelectric.com/articles/Switch_Ratings.pdf Switch "ratings" are not a common language among all manufacturers of switches . . . else there would not be so many ratings standards by which the folks who write rules for aforementioned games can choose. Further, the ratings games are crafted with the revenue generating applications (down time on a $high$ machine costs many times more than the value of the switch), safety issues in both industrial and military hardware (switch failure increases risk of injury or death). In the OBAM aircraft environment, we assume risks of for lack of knowledge and craftsmanship that are generally considered to be very low numbers in the commercial, industrial and military worlds. Hence my vociferous suggestions that we place failure tolerance above all other considerations for the design, operation and maintenance of our airplanes. A search of the accident archives reveals that failures of electrical system components in light aircraft account for a tiny proportion of causation for the accident. In those situations where electrical failures were prominent players, it was easy to deduce in hindsight how that stack-up of events could have been comfortably managed by the failure tolerant aircraft flown by a knowledgeable pilot. I don't recall reading ANY accident analysis where failure of a component to perform as advertised was a contributing factor. No doubt there are SOME such reports but I've not found one yet. It's been my suggestion for years of participation first on Compuserve AVSIG and later here on the Matronics Lists that we can design, fabricate and operate airplanes using the most ordinary components and still enjoy very low risk use of the airplane's electrical system. This is especially true of machines that get on average, 50 hours of service per year as opposed to machines that run 1000's of hours per year. Bob . . . ________________________________________________________________________________
Date: Dec 28, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: "engineers"
OK, this is not the correct venue to discuss this sort of thing. I'm the biggest complainer of abuse of this email list and now I'm guilty. Please don't reply to the list about this thread...if you want to continue we'll find another venue . . . Is this not a venue for the exchange of simple-ideas and their incorporation into recipes for success? When an idea/recipe is offered, is it not useful to gage potential quality of the idea against the demonstrated history of the offerer? While few of us here on the List have credentials framed on our walls, we ALL have experiences and talents that qualify us as teachers. Depending on the sum total of life experiences and demonstrated achievements, some of us have more to offer than others. But no combination of simple-ideas into any recipe for success becomes less valuable just because the offerer "is not qualified" based on some arbitrary standard. An argument was proposed that lack of recognized credential placed the value of ideas or the integrity/motivations of some offerers in doubt. I'll suggest that comparative study of demonstrable achievement versus credential-based stature in this community is useful to the goals of this List. Bob . . . ________________________________________________________________________________
Date: Dec 28, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Good website
At 02:03 AM 12/28/2009, you wrote: >Folks; >Many of you probably know about these places but some may not. I >found the prices to be reasonable. > ><http://www.wiringproducts.com/index.html>http://www.wiringproducts.com/index.html An impressive site . . . with caution. Terminals offered are not PIDG style and there are good reasons to avoid glass cartridge fuses. No doubt there are numerous products offered that are useful to the OBAM aircraft builder but if in doubt, ask about a product being considered here on the List first . . . Bob . . . ________________________________________________________________________________
Date: Dec 28, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Tube and Fabric Ground Plane
At 08:31 AM 12/28/2009, you wrote: > > >Some builders have mounted the antenna inside of the 4130 tube fuselage, >which has the best crash resistance; but, I would think that the fuselage >would be a great faraday cage and would thus limit the transmission >considerably. Yes. Don't do this . . . >For these reasons I'd prefer to mount the antenna on the top of the fuselage >behind the cabin. In this particular fuselage there are non-structural >stringers that protrude about 3 inches above the primary structure, so I was >planning to make a bracket to use as a mount for the antenna. The bracket >would be shaped like an upside down U with the top of the bracket even with >the top of the stringers, so that the antenna would attach at the top of the >bracket and the bottom legs would be welded to either side of a crossing >tube. How should I provide for a ground plane? Make sure you have good electrical connection to the bracket that is welded to the tube. This can be accomplished by mate up pressures of attaching hardware even when intermediate layers include insulating materials. > The stringers are aluminum >and about 12 inches apart, and the steel fuselage is about 3" below the base >of the antenna. Would it be a good idea to use either of those as part or >all of the ground plane, or would it be better to make something out of >copper foil and try to insulate that ground plane from the airframe parts? >Any thoughts? Foil ground plane strips on the inside of the fabric would be useful but probably wouldn't increase performance greatly. The BIG design problem is one of mechanical robustness. Getting your antenna mounted to solid structure through your proposed bracket will go a long way toward a low maintenance and adequately performing system. Of course the feedline shield needs to get a good electrical connnection to the same bracket. Bob . . . ________________________________________________________________________________
Subject: Questions: 17-5 & Sizing
Date: Dec 28, 2009
From: "Perry, Phil" <Phil.Perry(at)netapp.com>
Hi, I've been a lurker for awhile, mainly because I haven't had to think too much about the electrical system of the airplane yet. There is no doubt that I'll be covering some well plowed ground with these questions, but maybe you can help get me off high-center. I am building an all glass RV-10 and I don't plan on using Electronic Ignition. My first question involves figure 17-5 (Dual Alternator, Dual Battery Electrical System). The narrative discussion on the crossfeed contactor is a little light and I'm having a hard time getting a handle on that diagram. 1) I'd like to understand how the cross feed functions. a. Is it an automatic switch? b. Is it closed during normal operations? c. I'm guessing it's just like any other contactor and requires ~1 Amp current to maintain closure? 2) Still on 17-5, couldn't there be a diode placed between the "Main Battery" and the "Main Bus"? For the cost of a diode, you could add a secondary path that is independent of any contactor. The chances of needing to use it is highly unlikely, but it's a really cheap way to save 2-3 Amps (Main Bat Contactor, Aux Bat Contactor, Cross Feed Contactor) if you ever need to shed off load. 3) Finally I'm not finding much in the way component sizing. Meaning I'm trying to figure out which specific diodes I will need. Which specific model numbers/sizes of contactors I will need. Thanks for the help. As I get the architecture laid out, I'll share it for review. Thanks, Phil ________________________________________________________________________________
Date: Dec 28, 2009
From: RScott <rscott(at)cascadeaccess.com>
Subject: Where is the missing atmospheric carbon dioxide?
The models say it should be there, but it's not! We've gotta find it--our models are right, because they all agree! http://www.reuters.com/article/idUSTRE50S6CW20090129 http://www.icsu-visioning.org/2009/07/where-is-the-missing-atmospheric-carbon-dioxide/ Oh, but the way, the satellite failed--I don't know if the missile crashed or if the satellite just didn't work. The Canadians built one for .01% of our cost. ________________________________________________________________________________
Subject: Re: dynon fuel pressure sensor location on 912s
From: "Geoff Heap" <stol10(at)comcast.net>
Date: Dec 29, 2009
Chris. There is a takeoff you can use. It's from the fuel cross connect between the carbs. I think thats what its for actually. I ran a hose from there to the firewall where I attached the sensor that came with my Dynon However I have to disconnect it soon and add a restrictor. I need to determine what fitting would be compatible for my setup but Yes, Definitely. We both need restrictors. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279082#279082 ________________________________________________________________________________
Subject: Re: Questions: 17-5 & Sizing
From: "user9253" <fran4sew(at)banyanol.com>
Date: Dec 29, 2009
Phil, This is the way that I understand it. 1A. The cross feed switch is not automatic. You have to manually operate it. Center is off. Up (momentary spring-back) starts the engine using both batteries. Down is on. 1B. You would only move the switch into the down position if one of the alternators failed. 1C. Probably 2. If a diode connects the battery to the Main Power Bus, then how would you shut off the power in case of smoke in the cockpit? You can accomplish your goal of adding a secondary path that is independent of any contactor by using an essential bus switch. See Bob Nuckolls' drawing Z-13/8. I do not have figure 17-5 that you refer to. From your description, it sounds similar to Z-14. I think that Z-14 is desirable for flight over very long distances over hostile terrain. But for travel within the contiguous U.S.A., Z-13/8 is more than adequate. Using Z-13/8, your RV-10 will have a more reliable electrical system than most type certificated small planes. And it will be lighter, less expensive, and simpler than Z-14. 3. The diodes used for arc suppression are 1N5400 available at http://www.mouser.com/ProductDetail/Fairchild-Semiconductor/1N5400/?qs=sGAEpiMZZMtEwUVCuofpuI3LdHjUmCjoSwNVLo%2fSo6g%3d The AeroElectric Connection sells a diode for the essential bus at http://www.mouser.com/ProductDetail/Fairchild-Semiconductor/1N5400/?qs=sGAEpiMZZMtEwUVCuofpuI3LdHjUmCjoSwNVLo%2fSo6g%3d Here is another suitable diode for the essential bus with a slightly higher voltage drop: http://www.mouser.com/ProductDetail/Fairchild-Semiconductor/GBPC2510/?qs=sGAEpiMZZMtcLAek5QF0i29EdKsLUhPgdV8BgFVVYoM%3d Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279088#279088 ________________________________________________________________________________
Date: Dec 29, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Questions: 17-5 & Sizing
At 07:59 PM 12/28/2009, you wrote: Hi, I've been a lurker for awhile, mainly because I haven't had to think too much about the electrical system of the airplane yet. There is no doubt that I'll be covering some well plowed ground with these questions, but maybe you can help get me off high-center. I am building an all glass RV-10 and I don't plan on using Electronic Ignition. My first question involves figure 17-5 (Dual Alternator, Dual Battery Electrical System). The narrative discussion on the crossfeed contactor is a little light and I'm having a hard time getting a handle on that diagram. 1) I'd like to understand how the cross feed functions. a. Is it an automatic switch? b. Is it closed during normal operations? c. I'm guessing it's just like any other contactor and requires ~1 Amp current to maintain closure? Yes, it's just like the battery contactors. It is closed for engine cranking so that both batteries can be used to start the engine. It's open for all normal operations. IF one alternator fails and IF your plan-b operations protocols call for sharing the output one alternator with the entire system, then you can close it manually for remainder of flight. 2) Still on 17-5, couldn't there be a diode placed between the "Main Battery" and the "Main Bus"? For the cost of a diode, you could add a secondary path that is independent of any contactor. The chances of needing to use it is highly unlikely, but it's a really cheap way to save 2-3 Amps (Main Bat Contactor, Aux Bat Contactor, Cross Feed Contactor) if you ever need to shed off load. Why are you considering 17-5? The same system is described in more detail in the Appendix Z as figure Z-14. This system is much more expensive, heavier and takes up more volume in the airplane than say Z-13/8 . . . 3) Finally I'm not finding much in the way component sizing. Meaning I'm trying to figure out which specific diodes I will need. Which specific model numbers/sizes of contactors I will need. You need to conduct a load analysis and then craft how you plan to use installed systems under the various failure modes. Figure Z-13/8 is probably everything that 99% of OBAM aircraft needs. It's lighter, simpler, a whole lot less expensive and offers system reliability on a par with a King Air. You won't find detail sizing information as the drawings are intended to be starting points for an architecture. Exact sizing of breakers, wire, and indeed electrical energy sourcing for each system still needs to be developed by the builder. How do you perceive that Z-13/8 will not meet your needs? Bob . . . ________________________________________________________________________________
Date: Dec 29, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Where is the missing atmospheric carbon dioxide?
At 10:09 AM 12/29/2009, you wrote: >Matt, > >This one was able to sneak past you. Doesn't belong on this forum. > >Thanks, > >Roger I'm not sure that Matt has any direct screening duties on the individual lists. I've already written to Scott about the posting. Bob . . . ________________________________________________________________________________
From: "Terry Watson" <terry(at)tcwatson.com>
Subject: Where is the missing atmospheric carbon dioxide?
Date: Dec 29, 2009
Could this be an instance of a hijacked email address? I quite regularly get spam where the sender is shown as me. There doesn't seem to be anything I can do about it. If anyone has any suggestions I would be interested. Yes, I use firewalls and spam filters and virus scanners. Terry - if you got a Viagra email with my return address on it, I didn't do it! From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Tuesday, December 29, 2009 10:07 AM Subject: RE: AeroElectric-List: Where is the missing atmospheric carbon dioxide? At 10:09 AM 12/29/2009, you wrote: Matt, This one was able to sneak past you. Doesn't belong on this forum. Thanks, Roger I'm not sure that Matt has any direct screening duties on the individual lists. I've already written to Scott about the posting. Bob . . . ________________________________________________________________________________
Date: Dec 29, 2009
From: D Fritz <dfritzj(at)yahoo.com>
Subject: Re: Battery Equalizers
Bob et al, I appreciate the architecture advice and will take it into consideration. - Unfortunately, I'm on a work-driven building hiatus that'll probably ke ep me from doing any work on the Velocity for at least a couple years, so I won't be able to give any solid feedback on the usefulness of a battery eq ualizer in this setup for a while.- In the meantime, I can do a quick tra de study to look at the cost and parts count between the multiple bus setup and replacing the hydraulic power pack and associated control circuits. I don't know if you looked at the link to the white paper in my previous po st or not, but in it the author shows significant experimental improvement in battery life using an equalizer in a series string of batteries.- As I need a 24V system in my aircraft anyway and will be using two batteries in series, it makes sense to me to take advantage of these improvements if in fact the claims are true.- Have you (or anyone on the list) looked at th e white paper and/or have any knowledge or experience in the use and effica cy of these equalizers (regardless of whether I keep my multi-bus setup or not)? Thanks, Dan =0A=0A=0A ________________________________________________________________________________
Subject: Audio Question
From: "PaulR" <prose(at)panhandle.rr.com>
Date: Dec 29, 2009
I'm woefully short of 3 conductor shielded wire for wiring the headphone jacks but have plenty of 6 conductor shielded. Would it cause problems to use this in lieu of the separate pcs. of 3 conductor? I have a PSE intercom if that makes a difference. Also, the serial lines that Dynon, Garmin and about everyone else uses are shown both shielded and un-shielded. As long as ALL equipment utilizing the serial signals are grounded the same place (AVX GND) is it necessary to shield them? Thanks -------- Paul Rose N417PR (res) RV-9A Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279162#279162 ________________________________________________________________________________
Date: Dec 29, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Audio Question
At 07:31 PM 12/29/2009, you wrote: > >I'm woefully short of 3 conductor shielded wire for wiring the >headphone jacks but have plenty of 6 conductor shielded. Would it >cause problems to use this in lieu of the separate pcs. of 3 >conductor? I have a PSE intercom if that makes a difference. First, I've got a couple thousand feet of shielded triple, if that's what you'd LIKE to be using, I can make you a great deal on it. On the other-hand, twisted pairs in lieu of shielded wires will probably be just fine in the cockpit and behind the panel. Make sure the magneto p-leads are shielded and wired per Z-figures. After that, risks to other signals are very low. >Also, the serial lines that Dynon, Garmin and about everyone else >uses are shown both shielded and un-shielded. As long as ALL >equipment utilizing the serial signals are grounded the same place >(AVX GND) is it necessary to shield them? As short as they are and living in a behind the panel environment, twisted pairs are okay too along with any adaptation you care to devise with the 6 wire cable you already have. Bob . . . ________________________________________________________________________________
From: "Tim Andres" <tim2542(at)sbcglobal.net>
Subject: GNS 430
Date: Dec 30, 2009
I have a couple of questions re: the installation of a Garmin 430W. There are 7 separate power connections on the back of this unit. Two are labeled COMM, 1 "super flag" and the rest are labeled MAIN. There is nothing in the manual re: this other than the electrical load figures. What is common practice on these, 1 10 amp fuse & ganged together? I'm able to see the loads for the MAIN & COMM circuits so they could be fused separately. The second question is re: the "super flag", what is it? It shows as optional. I will not be using an indicator other than the GRT Horizons. Which by the way have a similar issue, that is 3 separate power inputs, which I understand from the manual how they work, but with an E bus and Brown out Batt. (Z-10/8) I think these will all be ganged together at the E-Bus fuse. There will be an Avionics master or at least an EFIS master as these units have no on/off switch, and GRT asks for one. I believe they would be protected anyway with Z-10/8 but I want to be able to shut down a misbehaving EFIS if needed. Thanks Tim Andres ________________________________________________________________________________
Date: Dec 30, 2009
From: Matthew Schumacher <schu(at)schu.net>
Subject: Re: GNS 430
Tim Andres wrote: > I have a couple of questions re: the installation of a Garmin 430W. > There are 7 separate power connections on the back of this unit. Two are > labeled COMM, 1 super flag and the rest are labeled MAIN. There is > nothing in the manual re: this other than the electrical load figures. > What is common practice on these, 1 10 amp fuse & ganged together? Im > able to see the loads for the MAIN & COMM circuits so they could be > fused separately. > I just got my 430W from Steinair. They made up power harnesses where P4002 has pins 11-12 ganged together to a single 18AWG wire and P4001 where pins 15,19,20,71 where all ganged together to a single 22AWG wire. I'm planning tying those together on the e-bus. Sorry I couldn't be more helpful, I'm just now sorting this out myself. schu ________________________________________________________________________________
Date: Dec 30, 2009
From: Matthew Schumacher <schu(at)schu.net>
Subject: Questions about circuit protection.
List, I'm finally closing in on completing my wiring diagram. I have the basics roughed in but wanted to get some review on it and also ask some specific questions about circuit protection: 1. Do my wire sizes look sane? I read though Bob's documentation on wire sizes and I think I have it mostly figured out, but wanted to double check. 2. I want to have an avionics master switch, but also an e-bus. Since the only 3 things I'm running on my e-bus are avionics, I decided to drive the ebus from the avionics bus though a diode. The goal is to be able to turn on the avionics master, then the ebus alternate feed. If I loose my master contactor or the avionics master switch, then my ebus will continue to work. I think I have eliminated all single points of failure while maintaining an avionics master. Can someone take a look and make sure I'm not missing something obvious? 3. My drawing is missing all of the circuit protection except for the ANL, and 5 amp breaker for the field coil. I want to add breakers for the rest, but I don't think I need a breaker for each device as that will get real expensive. Can I group up some of the lighting on a single breaker? Also, what about using a breaker for the entire e-bus then omitting the breakers for the devices on the ebus? The lines will be real short and it eliminates the single point of failure (breaker.) Also, what about fuselinks? I understand them to be like a fuse that blows extremely slowly, but I'm not fully understanding when and where to use them. Any thoughts or suggestions would be super!! schu ________________________________________________________________________________
From: "Bob-tcw" <rnewman(at)tcwtech.com>
Subject: Re: GNS 430
Date: Dec 31, 2009
Tim, The power inputs marked Aircraft Power 1 , P4001 pin 19,20 provide power to all the functions of the 430W except the comm radio and the super flag outputs, powering these inputs brings the GPS to life. The power inputs marked Aircraft Power 2, P4001 pin 15,72 are a redunant set of power inputs that do the same as aircraft power 1, these inputs are recommend for use with a second source of power to keep the gps system up and running in the event of loss of power on aircraft power 1. Also these inputs may be used with a product such as the TCW technologies IPS series of products that provide brown out protection down to 5 volts of bus voltage. see www.tcwtech.com to learn about these products. The power inputs marked Aircraft Power (comm) P4002 pin 11,12 provide power only to the communitcation radio. The power input marked Aircraft Power ( Nav super flags) P4006 pin 44 provides the power to drive the nav flags if you are separately driving various nav indicators connected to P4006 pin 15, 38 for vor/loc and glideslope. If you are not adding any separate indicators here then no power is required on this pin. hope this helps, Bob Newman TCW Technologies, LLC. www.tcwtech.com ----- Original Message ----- From: Tim Andres To: aeroelectric-list(at)matronics.com Sent: Thursday, December 31, 2009 12:59 AM Subject: AeroElectric-List: GNS 430 I have a couple of questions re: the installation of a Garmin 430W. There are 7 separate power connections on the back of this unit. Two are labeled COMM, 1 "super flag" and the rest are labeled MAIN. There is nothing in the manual re: this other than the electrical load figures. What is common practice on these, 1 10 amp fuse & ganged together? I'm able to see the loads for the MAIN & COMM circuits so they could be fused separately. The second question is re: the "super flag", what is it? It shows as optional. I will not be using an indicator other than the GRT Horizons. Which by the way have a similar issue, that is 3 separate power inputs, which I understand from the manual how they work, but with an E bus and Brown out Batt. (Z-10/8) I think these will all be ganged together at the E-Bus fuse. There will be an Avionics master or at least an EFIS master as these units have no on/off switch, and GRT asks for one. I believe they would be protected anyway with Z-10/8 but I want to be able to shut down a misbehaving EFIS if needed. Thanks Tim Andres ________________________________________________________________________________
From: "Rino" <lacombr(at)nbnet.nb.ca>
Subject:
Date: Dec 31, 2009
Bonne ann=E9e Camilla & Roger, Rino & Rita ________________________________________________________________________________
Date: Dec 31, 2009
From: James Robinson <jbr79r(at)yahoo.com>
Subject: Static Grounding
I fly a composite (E-glass not Carbon) Glasair and I am trying to deal with some static problems. A suggestion was to run a separate ground wire from radios stack , the EFIS and the AHRS directly to the ground buss as close to the battery as possible. Static wicks are not an option . Any comments or ideas? Jim James Robinson Glasair lll N79R Spanish Fork UT U77 ________________________________________________________________________________
Date: Dec 31, 2009
From: Ron Quillin <rjquillin(at)gmail.com>
Subject: Re: Power Opti-Miser
At 18:05 12/15/2009, you wrote: > The utility doesn't have to generate any extra watts. It only has > to choose wire sizes that carry an artificially high current that > doesn't participate in the running of devices with poor p.f. A year end article summary from an e-rag I read had a short commentary on PF issues that may be of some interest... Sorry I didn't recall it earlier in the thread. Ron Q. http://www.edn.com/blog/1470000147/post/450043045.html?nid=2431&rid=1968 165 > >Monday, April 6, 2009 > > >Utilities suffer from CFLs=92 poor power factor > > >Apr 6 2009 6:00PM | ><http://www.edn.com/blog/1470000147/post/450043045.html>Permalink >|<http://www.edn.com/blog/1470000147/post/450043045.html?nid=2431&rid=1 968165#comments>Comments >(96) | > >Every CFL light contains a small ac-dc power >supply with reactive components in it that will >affect the CFL=92s power factor (PF) ' that is, >the load presented to the ac line. The closer >the PF is to 1, the better. A load with low >power factor (<.85) draws more current and is >less efficient than a load with a high power >factor for the same amount of useful power. The >higher currents required by the lower PF devices >mean increased energy lost in the grid due to >such things as I2R losses. These power losses >don=92t show up directly on our electricity bill, >but the utilities sure see the effects. > >I put one of my home CFL bulbs on my Kill-O-Watt >power meter recently and measured its power >factor: It was .57. This is lousy. Although each >CFL is only 13W, there are millions of them out >there. Why no PF regulation, as there is of >higher-power, but less ubiquitous devices? > >I emailed Peter Banwell of the EnergyStar >program and asked if EnergyStar was considering >making minimum PF a requirement for Energy Star >compliance. He replied, =93We looked at this in >detail several years ago and decided against it, >though there are a couple of utilities that >still support the idea. We may take this up in >the future, as the market share grows, but right >now it is still in the noise in terms of impacts.=94 > >Coincidentally, after our email exchange I ran >into Mike Grather of ><http://www.luminairetesting.com/>Luminaire >Testing Laboratory. He recently ran a series of >life-cycle and performance tests on a batch of >100 CFLs with various power ratings averaging >approximately 20W each. They assumed a PF for >the lights of at least .75 and sized the power >supply at 3KVA. However, when they powered up >the bank of CFLs, the 3KVA supply was >inadequate. Grather checked the power factor for >the CFLs and found they ranged from .45 to .50. >Their =93real=94 load was about twice that implied by their wattage. > >CFLs are still an efficient form of household >lighting, but their poor PF number is leaving >money on the table. However, it=92s clear that at >about $2 each there=92s not a lot of room for >adding power factor correction circuitry. On the >other hand, utilities are already going to great >lengths to encourage consumers to switch to >CFLs, including subsidizing the price of CFLs. I >doubt that consumers would be interested in >paying more for a feature that actually benefits >the utility directly, not them. Perhaps >utilities will start to subsidize >high-power-factor CFLs, rather than the mediocre ones we can buy now. ________________________________________________________________________________
Date: Dec 31, 2009
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Static Grounding
At 10:59 AM 12/31/2009, you wrote: >I fly a composite (E-glass not Carbon) Glasair and I am trying to >deal with some static problems. A suggestion was to run a separate >ground wire from radios stack , the EFIS and the AHRS directly to >the ground buss as close to the battery as possible. Static wicks >are not an option . Any comments or ideas? If you're plagued with p-static in flight, then some form of surface treatment combined with static wicks are the only option. Grounds in the electrical system have no significance on this issue. P-static in all composite aircraft having no submerged lightning mesh has been a problem since day-one. It's not an electrical/electronics problem. Bob . . . ________________________________________________________________________________
Subject: Re: Static Grounding
From: "XeVision" <dblumel(at)XeVision.com>
Date: Dec 31, 2009
[quote="jbr79r(at)yahoo.com"]I fly a composite (E-glass not Carbon) Glasair and I am trying to deal with some static problems. A suggestion was to run a separate ground wire from radios stack , the EFIS and the AHRS directly to the ground buss as close to the battery as possible. Static wicks are not an option . Any comments or ideas? Jim James Robinson Glasair lll N79R Spanish Fork UT U77 > [b] I am in Ogden, UT and also fly a Glasair (I-RG) cruising at 200Kts Similar speeds (oversized engine 245 HP). Are you talking about static when flying through rain or snow ??? Or something else ?? When flying to Alaska a few years ago, Flying in some light snow at like 12-13K, I experienced such a static problem once that the cockpit was glowing and everything metal I touched shocked me. I made the mistake of touching the remote head (panel mounted control) for my ELT it it got "fried". All the radios were loud static noise and sometimes a howling sound. -------- LED still has a long way to go to compete with HID as a landing light. This is true in terms of total lumens and reach (distance). Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279463#279463 ________________________________________________________________________________
Date: Dec 31, 2009
From: James Robinson <jbr79r(at)yahoo.com>
Subject: Re: Static Grounding
I know I can't do much about the static, but I'm trying to do what ever I can to protect the avionics. James Robinson Glasair lll N79R Spanish Fork UT U77 ________________________________ From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> Sent: Thu, December 31, 2009 12:49:33 PM Subject: Re: AeroElectric-List: Static Grounding At 10:59 AM 12/31/2009, you wrote: > I fly a composite (E-glass not Carbon) Glasair and I am trying to deal with some static problems. A suggestion was to run a separate ground wire from radios stack , the EFIS and the AHRS directly to the ground buss as close to the battery as possible. Static wicks are not an option . Any comments or ideas? If you're plagued with p-static in flight, then some form of surface treatment combined with static wicks are the only option. Grounds in the electrical system have no significance on this issue. P-static in all composite aircraft having no submerged lightning mesh has been a problem since day-one. It's not an electrical/electronics problem. Bob . . . ________________________________________________________________________________
Date: Dec 31, 2009
From: James Robinson <jbr79r(at)yahoo.com>
Subject: Re: Static Grounding
I have been in and around clouds without any static like you mentioned but I lost the com port on my Chelton and the display screen on my TruTrak autopilot twice. James Robinson Glasair lll N79R Spanish Fork UT U77 ________________________________ From: XeVision <dblumel(at)XeVision.com> Sent: Thu, December 31, 2009 1:00:07 PM Subject: AeroElectric-List: Re: Static Grounding [quote="jbr79r(at)yahoo.com"]I fly a composite (E-glass not Carbon) Glasair and I am trying to deal with some static problems. A suggestion was to run a separate ground wire from radios stack , the EFIS and the AHRS directly to the ground buss as close to the battery as possible. Static wicks are not an option . Any comments or ideas? Jim James Robinson Glasair lll N79R Spanish Fork UT U77 > [b] I am in Ogden, UT and also fly a Glasair (I-RG) cruising at 200Kts Similar speeds (oversized engine 245 HP). Are you talking about static when flying through rain or snow ??? Or something else ?? When flying to Alaska a few years ago, Flying in some light snow at like 12-13K, I experienced such a static problem once that the cockpit was glowing and everything metal I touched shocked me. I made the mistake of touching the remote head (panel mounted control) for my ELT it it got "fried". All the radios were loud static noise and sometimes a howling sound. -------- LED still has a long way to go to compete with HID as a landing light. This is true in terms of total lumens and reach (distance). Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279463#279463 ________________________________________________________________________________
From: "Bruce Gray" <bgray(at)glasair.org>
Subject: Static Grounding
Date: Dec 31, 2009
Hi Bob, I'm building a Glasair III, an E-glass composite. While I don't have a metal mesh embedded in my skin, I was thinking of using a conductive vinyl ester primer bonded to static wicks to tame the P-static demon. Should I be concerned with the primer blocking the effectiveness of my internal COMM/NAV/GPS antennas? I suppose I could mask those areas and reshoot them with a normal primer but would that give me a rather directional radiation/reception pattern on my antennas? Is there any way I can test the effectiveness of a conductive primer on e-glass in p-static suppression before I bite the bullet? Bruce www.Glasair.org -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Thursday, December 31, 2009 2:50 PM Subject: Re: AeroElectric-List: Static Grounding At 10:59 AM 12/31/2009, you wrote: >I fly a composite (E-glass not Carbon) Glasair and I am trying to >deal with some static problems. A suggestion was to run a separate >ground wire from radios stack , the EFIS and the AHRS directly to >the ground buss as close to the battery as possible. Static wicks >are not an option . Any comments or ideas? If you're plagued with p-static in flight, then some form of surface treatment combined with static wicks are the only option. Grounds in the electrical system have no significance on this issue. P-static in all composite aircraft having no submerged lightning mesh has been a problem since day-one. It's not an electrical/electronics problem. Bob . . . ________________________________________________________________________________
From: "Allen Fulmer" <afulmer(at)charter.net>
Subject: GNS 430
Date: Dec 31, 2009
-- Tim said: -- There will be an Avionics master or at least an EFIS master as these units have no -- on/off switch, and GRT asks for one. I believe they would be protected anyway with -- Z-10/8 but I want to be able to shut down a misbehaving EFIS if needed. I too decided to put a DPDT switch on DU1 and 2 (each controls its respective AHRS)and a SPDT switch on DU3 (since no AHRS to control). I just did not like seeing all those screens come up every time I flipped the master switches on. So my MO would be to turn on the EIS and Master Switches while starting the engine and then turn on the EFIS/AHRS as needed. I have also noticed that the GTX337 transponder cannot be set to remain off when power is supplied. It will remain in the standby position but, once again, when I am playing and fiddling around I just hate to see it go up and down unnecessarily. Haven't decided on a switch for it or not. The PMA8000B and the 430W can be turned on with their own on/off switches. I know this might be different than Bob's suggestions minimizing single points of failure and component count but I think I will like it better. Allen Fulmer RV7 finishing the wiring ________________________________________________________________________________
Date: Dec 31, 2009
From: Joe Dubner <jdubner(at)yahoo.com>
Subject: Strobe Light Recommendation
Does anyone have a recommendation for a low-cost strobe light system (strobes only, no position lights)? I plan to put them on the sheared wingtips of a Van's RV-8A in concert with these position lights http://www.killacycle.com/Lights.htm (RV-style, not square-style or combo light style). I'm looking for something more economical than the Aeroflash $300 strobes, light weight, and 14V operation. Thanks, Joe Independence, OR http://www.mail2600.com/position http://www.mail2600.com/cgi-bin/webcam.cgi ________________________________________________________________________________
Date: Dec 31, 2009
Subject: Static Grounding
From: "Matt Prather" <mprather(at)spro.net>
I don't have an answer, but a bit of speculation.. I suspect that p-static doesn't build as a uniform voltage all over the airframe, but instead as a charge distribution along the pathway of high speed airflow. As such, I'd think you might be able to get rid of p-static by adding a conductive path roughly aligned with the flow. This allows bleeding the charge off quietly. The mesh is certainly the best solution for providing this path, but I could imagine that other techniques could be used. Conductive coatings seem like a reasonable thing to try. I imagine that they are somewhat process sensitive, and probably won't work as well as mesh - or a metal airframe. Depending on where your antennas are, you could probably get away with omitting the coating in these areas. I kind of suspect if the coating works well at warding off the p-static, it will also cause problems if used over the antennas, and if it doesn't work well, you could spray it everywhere and the antennas won't care. Matt- > > Hi Bob, > > I'm building a Glasair III, an E-glass composite. While I don't have a > metal mesh embedded in my skin, I was thinking of using a conductive > vinyl ester primer bonded to static wicks to tame the P-static demon. > Should I be concerned with the primer blocking the effectiveness of my > internal COMM/NAV/GPS antennas? I suppose I could mask those areas and > reshoot them with a normal primer but would that give me a rather > directional radiation/reception pattern on my antennas? > > Is there any way I can test the effectiveness of a conductive primer on > e-glass in p-static suppression before I bite the bullet? > > Bruce > www.Glasair.org > > -----Original Message----- > From: owner-aeroelectric-list-server(at)matronics.com > [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of > Robert L. Nuckolls, III > Sent: Thursday, December 31, 2009 2:50 PM > To: aeroelectric-list(at)matronics.com > Subject: Re: AeroElectric-List: Static Grounding > > > > At 10:59 AM 12/31/2009, you wrote: >>I fly a composite (E-glass not Carbon) Glasair and I am trying to >>deal with some static problems. A suggestion was to run a separate >>ground wire from radios stack , the EFIS and the AHRS directly to >>the ground buss as close to the battery as possible. Static wicks >>are not an option . Any comments or ideas? > > If you're plagued with p-static in flight, then > some form of surface treatment combined with > static wicks are the only option. Grounds in > the electrical system have no significance > on this issue. > > P-static in all composite aircraft having no > submerged lightning mesh has been a problem > since day-one. It's not an electrical/electronics > problem. > > Bob . . . > > ________________________________________________________________________________
From: "Bill Hibbing" <n744bh(at)bellsouth.net>
Subject: Comm and marker beacon antennas
Date: Dec 31, 2009
I'm thinking about building a comm dipole to put in my Glasair and am curious as to the need for any toroids on the feedline. I've got the dipole formula and an antenna analyzer for tuning it but the toroid question is what I need an answer to. I'll be mounting it in the interior of the airplane and it will be at least 3' from my other comm antenna. Next question...has anyone built a marker beacon antenna? As long as I'm building antennas I thought I might build one of these also. Bill Glasair SIIS-FT ________________________________________________________________________________
From: BobsV35B(at)aol.com
Date: Dec 31, 2009
Subject: Re: Comm and marker beacon antennas
Good Evening Bill, I have no knowledge concerning making an antenna, but may I ask why you want to install a marker beacon antenna? Or, for that matter, why you want a marker beacon receiver? The marker beacon is no longer a part of an ILS and very few enroute marker beacons are still in service in the US National Airspace System. An IFR approved GPS position can legally be used for any function that might otherwise require gaining a position via a marker beacon. It is not much more useful than would be a low frequency receiver that will allow you to shoot a four course low frequency range approach. Save your time and money and forget that ancient antique. It is no longer needed for any modern approach. Many of the beacons that are still shown on approaches have been notamed out of service because components are no longer available to repair the units. Once again, the very few positions that might use a beacon can be more easily and accurately located via an IFR approved GPS. Happy Skies, Old Bob AKA Bob Siegfried Downers Grove, Illinois Stearman N3977A In a message dated 12/31/2009 9:29:32 P.M. Central Standard Time, n744bh(at)bellsouth.net writes: I'm thinking about building a comm dipole to put in my Glasair and am curious as to the need for any toroids on the feedline. I've got the dipole formula and an antenna analyzer for tuning it but the toroid question is what I need an answer to. I'll be mounting it in the interior of the airplane and it will be at least 3' from my other comm antenna. Next question...has anyone built a marker beacon antenna? As long as I'm building antennas I thought I might build one of these also. Bill Glasair SIIS-FT ________________________________________________________________________________
Date: Dec 31, 2009
From: Ron Quillin <rjquillin(at)gmail.com>
Subject: Re: Comm and marker beacon antennas
At 19:47 12/31/2009, you wrote: >The marker beacon is no longer a part of an ILS and very few enroute >marker beacons are still in service in the US National Airspace >System. An IFR approved GPS position can legally be used for any >function that might otherwise require gaining a position via a marker beacon. > >It is not much more useful than would be a low frequency receiver >that will allow you to shoot a four course low frequency range >approach. Save your time and money and forget that ancient antique. >It is no longer needed for any modern approach. I won't disagree, but the LOC-D approach at my home 'drome, KSEE, with a FM, allows descent from 2700 to 1580. So, lacking that approach certified GPS, it -can- still be useful... Ron Q. ________________________________________________________________________________
From: "Tim Andres" <tim2542(at)sbcglobal.net>
Subject: Comm and marker beacon antennas
Date: Dec 31, 2009
RST has an antenna kit that supplies the formula for what you want to do as well as the instructions for installing in a glass airframe and the toroids you need. You can gather all this yourself if you want to go to the trouble, the only difficult thing to find are the torroids but they are out there and someone will know where to get them. Tim _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bill Hibbing Sent: Thursday, December 31, 2009 7:22 PM Subject: AeroElectric-List: Comm and marker beacon antennas I'm thinking about building a comm dipole to put in my Glasair and am curious as to the need for any toroids on the feedline. I've got the dipole formula and an antenna analyzer for tuning it but the toroid question is what I need an answer to. I'll be mounting it in the interior of the airplane and it will be at least 3' from my other comm antenna. Next question...has anyone built a marker beacon antenna? As long as I'm building antennas I thought I might build one of these also. Bill Glasair SIIS-FT ________________________________________________________________________________
From: "William Hibbing" <n744bh(at)bellsouth.net>
Subject: Re: Comm and marker beacon antennas
Date: Dec 31, 2009
Bob and Ron, Thanks for the info. I guess I probably knew that but thought that since the audio panel already had a MB rcvr in it I could build an el cheapo antenna. I know I'm not willing to spend any money on trying to receive an obsolete system. I've decided to splurge and put in a second comm radio/gps so that's why I've got an audio panel now...didn't need it with just one comm/gps. Well, actually I'm putting in a bit more. Bill ----- Original Message ----- From: Ron Quillin To: aeroelectric-list(at)matronics.com Sent: Thursday, December 31, 2009 11:02 PM Subject: Re: AeroElectric-List: Comm and marker beacon antennas At 19:47 12/31/2009, you wrote: The marker beacon is no longer a part of an ILS and very few enroute marker beacons are still in service in the US National Airspace System. An IFR approved GPS position can legally be used for any function that might otherwise require gaining a position via a marker beacon. It is not much more useful than would be a low frequency receiver that will allow you to shoot a four course low frequency range approach. Save your time and money and forget that ancient antique. It is no longer needed for any modern approach. I won't disagree, but the LOC-D approach at my home 'drome, KSEE, with a FM, allows descent from 2700 to 1580. So, lacking that approach certified GPS, it -can- still be useful... Ron Q. ________________________________________________________________________________
From: "Don" <dsvs(at)ca.rr.com>
Subject: Comm and marker beacon antennas
Date: Dec 31, 2009
Bill, The market beacon antenna is 40 inches of copper foil or the sane length of coax with the shield removed. Position it for to aft and horizontal and it will work fine. Mine is in a glass wing tip on my RV DonVS RV7 flying From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bill Hibbing Sent: Thursday, December 31, 2009 7:22 PM Subject: AeroElectric-List: Comm and marker beacon antennas I'm thinking about building a comm dipole to put in my Glasair and am curious as to the need for any toroids on the feedline. I've got the dipole formula and an antenna analyzer for tuning it but the toroid question is what I need an answer to. I'll be mounting it in the interior of the airplane and it will be at least 3' from my other comm antenna. Next question...has anyone built a marker beacon antenna? As long as I'm building antennas I thought I might build one of these also. Bill Glasair SIIS-FT ________________________________________________________________________________
From: BobsV35B(at)aol.com
Date: Jan 01, 2010
Subject: Re: Comm and marker beacon antennas
Good Evening Ron, That particular approach was what got me interested in the current status of marker beacons. A few of years ago, I wanted to shoot that approach, but the marker beacon was listed as being out of service so the minima was very high. I checked with the local FEDS and was told that it was highly unlikely that the fan marker would ever be returned to service as they were having trouble finding parts for the repair. I had an IFR approved GPS, but under the AIM interpretation of that time, substitution of a GPS measurement was not approved. (That interpretation in the AIM has since been changed) There was no intersection listed to be used in place of the Fan Marker. I requested that an intersection be named so that we could use that intersection in lieu of the fan marker. That intersection was then designated so under the old AIM interpretation we could use the GPS in lieu of the fan marker. I asked whether or not a radar fix from the tower could be used in lieu of the marker. I was told that such use was dependent on whether or not the particular controller who was working that position was radar qualified. The last statement was NOT agreed to by all of the FEDs with whom I spoke. The last time I was at KSEE was last spring for the Beechcraft Heritage Museum spring board meeting and the fan marker was still inoperative, but with the new intersection available, there was no question as to whether or not the GPS could be used. Is that marker beacon now back in service? I would be very interested in any other example within the US National Airspace System where a marker beacon is still required and a GPS cannot be substituted. I think we can get such a situation rectified if we try. It worked at your home drome! Happy Skies, Old Bob In a message dated 12/31/2009 11:06:14 P.M. Central Standard Time, rjquillin(at)gmail.com writes: At 19:47 12/31/2009, you wrote: The marker beacon is no longer a part of an ILS and very few enroute marker beacons are still in service in the US National Airspace System. An IFR approved GPS position can legally be used for any function that might otherwise require gaining a position via a marker beacon. It is not much more useful than would be a low frequency receiver that will allow you to shoot a four course low frequency range approach. Save your time and money and forget that ancient antique. It is no longer needed for any modern approach. I won't disagree, but the LOC-D approach at my home 'drome, KSEE, with a FM, allows descent from 2700 to 1580. So, lacking that approach certified GPS, it -can- still be useful... Ron Q. (http://www.aeroelectric.com/) (http://www.buildersbooks.com/) (http://www.homebuilthelp.com/) (http://www.matronics.com/contribution) (http://www.matronics.com/Navigator?AeroElectric-List) ________________________________________________________________________________
Date: Jan 01, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Comm and marker beacon antennas
At 09:21 PM 12/31/2009, you wrote: >I'm thinking about building a comm dipole to put in my Glasair and >am curious as to the need for any toroids on the feedline. I've got >the dipole formula and an antenna analyzer for tuning it but the >toroid question is what I need an answer to. I'll be mounting it in >the interior of the airplane and it will be at least 3' from my >other comm antenna. The toroids add no value. Install and cut to lowest SWR at your center-frequency of interest. > >Next question...has anyone built a marker beacon antenna? As long >as I'm building antennas I thought I might build one of these also. Marker beacons are so strong that a wet string will nearly suffice. Hook a 40' piece of 22AWG wire into the antenna connector and tape it to the inside of the fuselage in as "strung out straight" as possible. But GPS offers better identification of the markers. Many markers are not being repaired as they crap out. Bob . . . ________________________________________________________________________________
From: "Keith Burris" <klburris(at)frontiernet.net>
Subject: Re: Static Grounding
Date: Jan 01, 2010
James: You wrote: I fly a composite (E-glass not Carbon) Glasair and I am trying to deal with some static problems. A suggestion was to run a separate ground wire from radios stack , the EFIS and the AHRS directly to the ground buss as close to the battery as possible. Static wicks are not an option . Any comments or ideas? Jim James Robinson Glasair lll N79R Spanish Fork UT U77 My thoughts: I fly a Titan Tornado, which is mostly a spam can but it has a fiberglass nose cone. I use an Icon. The reception I got with a standard Comant mounted on the ground plane was remarkable in that I was unable to get weather while on the ground. I could hear a buddy at the end of the runway but he then got lost in static. I found the following end fed (not supposed to work) dipole antenna: http://www.miracleantenna.com/AirWhip.htm which, for me, solved all my problems. I can now hear people in Nephi when I m on the ground at Fillmore or Delta. This company also has a noise filter (Smoothie Brickwall Noise Filter) which could end up giving you complete isolation from the aircraft with some radio mounting changes. I have no idea if this would solve any p static issues as I dont have those but it might be worth a call. The guy that runs the place is named Robert, and is very helpful. Hope this helps. (BTW, my cousin has a Glasair III, a Glasair I and a KR-2. The Glassair III is a downright blast to fly when you fly it like an ultralight ;-) * Keith * Kanosh, UT (Kanosh International, 800, 0-36) ________________________________________________________________________________
Date: Jan 01, 2010
From: Ron Quillin <rjquillin(at)gmail.com>
Subject: Re: Comm and marker beacon antennas
Some interesting history, thanks Bob. I just pulled up the current LOC-D approach chart. GRIGG FM is still on the chart but seems to lack any information identifying it as an intersection on the chart, as do both SAMOS and BARET the IAF and FAF's. However, lighting up my 480 sim, I find it is in the DB as an intersection. I flew the approach a few months ago in a non-gps PA-22; and GRIGG was indeed, in service. Ron Q. At 23:33 12/31/2009, you wrote: >From: BobsV35B(at)aol.com > >Good Evening Ron, > >That particular approach was what got me interested in the current >status of marker beacons. > >A few of years ago, I wanted to shoot that approach, but the marker >beacon was listed as being out of service so the minima was very >high. I checked with the local FEDS and was told that it was highly >unlikely that the fan marker would ever be returned to service as >they were having trouble finding parts for the repair. > >I had an IFR approved GPS, but under the AIM interpretation of that >time, substitution of a GPS measurement was not approved. (That >interpretation in the AIM has since been changed) There was no >intersection listed to be used in place of the Fan Marker. I >requested that an intersection be named so that we could use that >intersection in lieu of the fan marker. That intersection was then >designated so under the old AIM interpretation we could use the GPS >in lieu of the fan marker. I asked whether or not a radar fix from >the tower could be used in lieu of the marker. I was told that such >use was dependent on whether or not the particular controller who >was working that position was radar qualified. The last statement >was NOT agreed to by all of the FEDs with whom I spoke. > >The last time I was at KSEE was last spring for the Beechcraft >Heritage Museum spring board meeting and the fan marker was still >inoperative, but with the new intersection available, there was no >question as to whether or not the GPS could be used. > >Is that marker beacon now back in service? > >I would be very interested in any other example within the US >National Airspace System where a marker beacon is still required and >a GPS cannot be substituted. I think we can get such a situation >rectified if we try. It worked at your home drome! > >Happy Skies, > >Old Bob ________________________________________________________________________________
From: n81jg(at)aol.com
Date: Jan 01, 2010
Subject: Re: GNS 430
H ________________________________________________________________________________
From: bobsv35b(at)aol.com
Date: Jan 01, 2010
Subject: Re: Comm and marker beacon antennas
Good Morning Ron, Glad to hear they found the parts! Took a couple of years though. I have been trying to research the necessity of having a marker beacon receiver and have been able to find very few places where it serves any purpose at all. There are several that are colocated with an NDB or where a DME distance can be used. Those approaches, generally localizer approaches, would need one of the following to shoot the approach. A DME, ADF, marker beacon receiver, IFR approved GPS, or a fix from a controller who is qualified to give that RADAR fix. They were removed as a requirement for ILS approaches several years ago. Many are still in service, but they are no longer required to be used. It is nice to be able to check the glide path intercept altitude at some sort of fix, but such a requirement does not exist in the routine US regulatory requirements. Some pilot examiners may not like it, but that is the way it goes! It's kinda like timing an approach. Fun to see if an applicant does so, but VERY rarely needed! Happy Skies, Old Bob In a message dated 1/1/2010 9:53:21 A.M. Central Standard Time, rjquillin(at)gmail.com writes: Some interesting history, thanks Bob. I just pulled up the current LOC-D approach chart. GRIGG FM is still on the chart but seems to lack any information identifying it as an intersection on the chart, as do both SAMOS and BARET the IAF and FAF's. However, lighting up my 480 sim, I find it is in the DB as an intersection. I flew the approach a few months ago in a non-gps PA-22; and GRIGG was indeed, in service. Ron Q. At 23:33 12/31/2009, you wrote: From: BobsV35B(at)aol.com Good Evening Ron, That particular approach was what got me interested in the current status of marker beacons. A few of years ago, I wanted to shoot that approach, but the marker beacon was listed as being out of service so the minima was very high. I checked with the local FEDS and was told that it was highly unlikely that the fan marker would ever be returned to service as they were having trouble finding parts for the repair. I had an IFR approved GPS, but under the AIM interpretation of that time, substitution of a GPS measurement was not approved. (That interpretation in the AIM has since been changed) There was no intersection listed to be used in place of the Fan Marker. I requested that an intersection be named so that we could use that intersection in lieu of the fan marker. That intersection was then designated so under the old AIM interpretation we could use the GPS in lieu of the fan marker. I asked whether or not a radar fix from the tower could be used in lieu of the marker. I was told that such use was dependent on whether or not the particular controller who was working that position was radar qualified. The last statement was NOT agreed to by all of the FEDs with whom I spoke. The last time I was at KSEE was last spring for the Beechcraft Heritage Museum spring board meeting and the fan marker was still inoperative, but with the new intersection available, there was no question as to whether or not the GPS could be used. Is that marker beacon now back in service? I would be very interested in any other example within the US National Airspace System where a marker beacon is still required and a GPS cannot be substituted. I think we can get such a situation rectified if we try. It worked at your home drome! Happy Skies, Old Bob ________________________________________________________________________________
Subject: Balancing Cockpit Lights
Date: Jan 01, 2010
From: "Perry, Phil" <Phil.Perry(at)netapp.com>
As I'm working through the schematics for my system, I've got annunciator lights for a handful of different scenarios. Low Voltage, Over Voltage, Flap Motor, etc..... Some of lights are included as parts of a subkit (IE: Voltage Reg) while others are built by me. I'm concerned that some lights will be brighter than others and they will not be uniformly lit on the panel. 1) What's the process for balancing lights? a. In-line resistors. Trial and Error until you find one you can live with? b. In-line Pots. You can adjust them individually behind the panel? c. Different light bulbs? Also, I'd ultimately like to put all of the cockpit lighting behind a single dimmer switch. I'm guessing that's accomplished by grounding all the lights to (and through) a dimmer switch. Correct? Thanks for the help. Have a happy and productive 2010. Phil ________________________________________________________________________________
From: <bakerocb(at)cox.net>
Subject: GTX337 ON or OFF?
Date: Jan 01, 2010
1/1/2010 Hello Allen Fullmer, You wrote: "........skip.....I have also noticed that the GTX337 transponder cannot be set to remain off when power is supplied. It will remain in the standby position but, once again, when I am playing and fiddling around I just hate to see it go up and down unnecessarily. Haven't decided on a switch for it or not." I also can not program my GTX327 to remain OFF when power is applied or reapplied to the avionics buss.** But the GTX327 has some options on which pins electrical power can be supplied to. If you pick the correct pin(s) the box will remain OFF until you push the ON button on the face of the box. I suspect that the GTX337 may be built the same way. So if you desire, and have the capability, you could rewire your GTX337 so that it would remain OFF until you pushed the ON button on the face of the box. 'OC' Says: "The best investment we can make is the effort to gather and understand knowledge." **PS: I suspect that the person who wired my panel set it up that way so that it would take a very deliberate OFF button action on my part in order to take off with the transponder OFF. I am with you, I'd like to have total ON - OFF control of the box with the buttons on the face of the box. ________________________________________________________________________________
Subject: THE VIRTUE OF SIMPLICITY
From: "racerjerry" <gki(at)suffolk.lib.ny.us>
Date: Jan 01, 2010
THE VIRTUE OF SIMPLICITY Parts left out cost nothing and cause no service problems. Parts left out also can cause no emergencies or smoke in the cockpit. I believe that the first statement was attributed to GMs Charles Boss Kettering. Henry Ford was a great advocate of the value of simplicity too; whether it be in life, in work or in play. If our missions often involve flying IFR at night, then a very good case can be made for all the backups, added equipment and redundancy advocated in this forum. What concerns me is that all the emergency procedures required to take advantage of redundant systems must be committed to writing and to memory; then must be tested, practiced and periodically rehearsed. With the increased costs of flying, TRUE currency becomes even more elusive. During an emergency, pilots rarely have time to look in their POH for emergency procedures; you will not have time either. When the adrenalin and sweat is flowing and when fear and tunnel vision sets in is not the time to begin learning emergency procedures. What is your plan to counter smoke in the cockpit? I have a plan. The FAA is currently saying that you need one too. If 99% of your planned missions are day VFR, think twice or 3 times, before going overboard on adding overly complicated equipment and redundant backup systems, much of which you barely understand. And dont forget that your airplane will perform better with less weight. -------- Jerry King Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279647#279647 ________________________________________________________________________________
Date: Jan 01, 2010
From: <mauledriver(at)nc.rr.com>
Subject: Re: Balancing Cockpit Lights
I don't think 'balancing' is a concern. They are all 'on' or 'off' and will get 12 volts when 'on'. I'm midway thru my dimming setup and it seems to me that I'll need 1 dimmer for all my Honeywell switches and indicators, another for cockpit map lighting, and I'm hoping only 1 for the various avionics that have dimmer functions. The last case may be an issue but I hope not. Bill 'the day after' Watson ---- "Perry wrote: > As I'm working through the schematics for my system, I've got > annunciator lights for a handful of different scenarios. Low Voltage, > Over Voltage, Flap Motor, etc..... > > > > Some of lights are included as parts of a subkit (IE: Voltage Reg) while > others are built by me. I'm concerned that some lights will be brighter > than others and they will not be uniformly lit on the panel. > > > > 1) What's the process for balancing lights? > > a. In-line resistors. Trial and Error until you find one you can > live with? > > b. In-line Pots. You can adjust them individually behind the > panel? > > c. Different light bulbs? > > > > Also, I'd ultimately like to put all of the cockpit lighting behind a > single dimmer switch. I'm guessing that's accomplished by grounding all > the lights to (and through) a dimmer switch. Correct? > > > > Thanks for the help. Have a happy and productive 2010. > > > > Phil > > > > > ________________________________________________________________________________
From: DCS317(at)aol.com
Date: Jan 01, 2010
Subject: Adding an antenna to improve on the ground reception?
Problem: On the ground at KAWO (non-towered airport) I can't get Seattle Center (and my IFR clearance) because of my RV-8 belly-mounted comm antenna. (In a high wing trainer, this is not a problem.) I have a bubble canopy--can I add an antenna within my canopy to the existing belly antenna with a combiner/splitter to my comm receiver and achieve better reception on the ground without degrading my in the air reception/transmission? Ground plane problem with this setup? I can't easily place another antenna on the top fuselage. Suggestions? Don Schmiesing ________________________________________________________________________________
Date: Jan 01, 2010
From: Jeff Page <jpx(at)qenesis.com>
Subject: Noise filter ?
On my Cessna 172, the strobe lights caused "tick" sounds. It was eliminated by placing a diode and then a large capacitor on the supply line to the audio panel, which reduced the brief dips in power when the strobe packs charged. In my Tundra, I effectively have the same setup. I plan to put a large capacitor on the essential bus, which is connected with a bridge rectifier as in Z13/8. However, my second radio is on my main bus. Should I stick a diode and capacitor in its feed line after the fuse ? Or should I plan instead to rectifiy any noise issues if I actually have them ? My anti-collision lights will be LEDs, not strobes, but I tend to think clean power is good power. Jeff Page Dream Aircraft Tundra #10 ________________________________________________________________________________
Date: Jan 01, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: THE VIRTUE OF SIMPLICITY
At 02:20 PM 1/1/2010, you wrote: THE VIRTUE OF SIMPLICITY "Parts left out cost nothing and cause no service problems." Parts left out also can cause no emergencies or smoke in the cockpit. I believe that the first statement was attributed to GM's Charles "Boss" Kettering. Henry Ford was a . . . CFK is one of my heros. Purty smart fellow . . . If 99% of your planned missions are day VFR, think twice or 3 times, before going overboard on adding overly complicated equipment and redundant backup systems, much of which you barely understand. And don't forget that your airplane will perform better with less weight. Dead on right! The simplest, lightest, and most profound adaptations of legacy TC electrical systems to OBAM aircraft was the conversion of an "avionics bus" to a "dual feed-path endurance bus" and replacement of the vacuum pump with an SD-8. This produced a system for less weight and several-fold improvement in system reliability. In other words, Z-13/8 gives you system reliability of the system in a King Air but with the addition of only one switch (S/B Alt Control). Further, there are NO combinations of mis-positioned switches that put the system at risk for exacerbating a failure event. Any contemplated departure from Z-13/8 (or any other Z-figure) should be evaluated for validity of design goals. I receive many direct inquiries from folks who say they've read the book, studied chapter 17 and then ask for an evaluation of their particular recipe for success. The system generally consists of cherry-picked features from the Z-figures stirred into their personal desires/worries. I have to remind folks that each Z-figure speaks to an architecture crafted to a design goal. Further, each drawing as-depicted has a high-order probability of being the elegant solution for an electrical system in one aircraft out of 99.9% of OBAM aircraft under construction. Adding switches, busses, back-ups to the back-ups and similar exercises will generally have a poor return on investment in complexity, weight, and cost-of-ownership. It's relatively easy to add perceived "enhancements" but with a risk of inserting new failure modes along with the certainty of increasing weight, complexity and cost of ownership. But as Jerry pointed out, ideas that seem to add comfort for perceived concerns may backfire by adding complexity that the pilot has to sort out when things are NOT going well in the cockpit. I've written extensively about dark-n-stormy night stories that offer little in the way of understanding while generating new worries amongst those who have the least understanding of how the system works. So just a friendly heads-up for those working on progressive evolution of the z-figures: If your design goal is to embark upon a new expedition into experimentation, you're certainly free to do so. We are, after all building EXPERIMENTAL airplanes . . . or are we? On the other hand, if one desires to tap the collective knowledge, understanding and willingness here on the List to teach, then consider questioning any perceived shortfall in the Z-figures before you spend a lot of $time$ cutting and pasting. The majority of folks on the List are interested in seeing just how FEW parts we can assemble in the MOST elegant combination to MAXIMIZE failure tolerance of your project's electrical system. Bob . . . ________________________________________________________________________________
Date: Jan 01, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Questions about circuit protection.
At 01:38 AM 12/31/2009, you wrote: List, I'm finally closing in on completing my wiring diagram. I have the basics roughed in but wanted to get some review on it and also ask some specific questions about circuit protection: 1. Do my wire sizes look sane? I read though Bob's documentation on wire sizes and I think I have it mostly figured out, but wanted to double check. Keep in mind that the "ratings" for how wire is used in airplanes is conservative to the extreme. A wire is not in danger of heating to copper-melting temperatures should you exceed the "rating" by say TWICE or event 4X. See: http://aeroelectric.com/Pictures/Wire/22AWG_20A.pdf that 22AWG wire in the foreground has been carrying 20Amps until the insulation temperature was seen to stabilize at about 112C . . . the wires INSULATION is RATED for 150C. So even at 4X the current we normally rate the wire for in aircraft bundles, it's not in danger of smoking it's insulation . . . and WAAaaaayyy too cold to melt the wire. Now, the voltage drop in this wire at 20A is terrible. Unless the wire run were limited to a few inches, we'd choose to upsize the wire if only for that reason. 2. I want to have an avionics master switch, but also an e-bus. Since the only 3 things I'm running on my e-bus are avionics . . . Why not simply add a switch in series with your e-bus normal feed path diode and label it "Avionics Master". Then ditch the avionics bus and run your avionics of concern along with endurance necessities from the e-bus. I decided to drive the ebus from the avionics bus though a diode. The goal is to be able to turn on the avionics master, then the ebus alternate feed. If I loose my master contactor or the avionics master switch, then my ebus will continue to work. I think I have eliminated all single points of failure while maintaining an avionics master. Can someone take a look and make sure I'm not missing something obvious? As suggested in my post of a few minutes ago, what operational problems do you perceive with Z-11 as published? 3. My drawing is missing all of the circuit protection except for the ANL, and 5 amp breaker for the field coil. I want to add breakers for the rest, but I don't think I need a breaker for each device as that will get real expensive. As describe in http://www.aeroelectric.com/articles/fuseorcb.html http://www.aeroelectric.com/articles/fusvbkr2.html Fuses are 1:1 interchangeable with breakers for their intended purpose . . . keep wires from burning and keep faults in one feeder from propagating to other segments of the whole system. Why would you want one set of busses with breakers and yet other busses with fuses? Can I group up some of the lighting on a single breaker? Also, what about using a breaker for the entire e-bus then omitting the breakers for the devices on the ebus? The lines will be real short and it eliminates the single point of failure (breaker.) Also, what about fuselinks? I understand them to be like a fuse that blows extremely slowly, but I'm not fully understanding when and where to use them. It's not clear that you've latched onto what fuses and breakers are all about. I'll suggest that you re-consider fuse blocks for ALL busses and one fuse per accessory. Quick, light, easy to install, and inexpensive. Bob . . . ________________________________________________________________________________
Date: Jan 01, 2010
From: Matthew Schumacher <schu(at)schu.net>
Subject: Re: Questions about circuit protection.
First, thank you very much for looking at my stuff Bob. I greatly appreciate it and have donated to keep this list going... Robert L. Nuckolls, III wrote: > > Keep in mind that the "ratings" for how wire is used > in airplanes is conservative to the extreme. A wire > is not in danger of heating to copper-melting temperatures > should you exceed the "rating" by say TWICE or event 4X. Got it, I'll go back and thin some of it out then double check. > 2. I want to have an avionics master switch, but also an e-bus. Since > the only 3 things I'm running on my e-bus are avionics . . . > > Why not simply add a switch in series with your > e-bus normal feed path diode and label it > "Avionics Master". Then ditch the avionics bus > and run your avionics of concern along with > endurance necessities from the e-bus. It is my understanding that the purpose of the e-bus is to be able to open the battery contactor and instantly have the system load drop to whatever is on the e-bus making it easier and quicker for the pilot to shed unneeded load in the event of an alternator failure. To that end I put only required avionics on the e-bus and avionics that I don't absolutely need to have on an avionics bus thinking that this was in line with the design goals of using an e-bus. > > As suggested in my post of a few minutes ago, what operational > problems do you perceive with Z-11 as published? > I read the prior post and see your point about cut-and-pasting elements of various diagrams together which results in a more complex electrical system, but in the case of Z-13/8, the drawing lacks an avionics bus which means that everything plugged into the e-bus or main bus will be powered on when the master contactor closes, and will remain on while the starter is operating. My drawing mirrors Z-13/8 except for adding an avionics bus and a switch, which adds complexity, but in return, my avionics can be powered off during start, and turning off the avionics master but leaving the e-bus on instantly sheds load that isn't absolutely necessary. This change does not add a single point of failure for critical avionics, however it does add a point of failure for non-critical avionics (switch.) So my question is this: Given that simple is always cheaper/lighter/more reliable, is it worth the weight/cost/complexity to add a bus and a switch so that I can keep my avionics off during start, and be able to instantly shed all non-critical loads? I thought it was, but it seems like you disagree. Also, what are others doing here? Are they simply using the built in power switch to turn stuff off at start (if the component has a built in switch.) > Can I group up some of the lighting on a > single breaker? Also, what about using a breaker for the entire e-bus > then omitting the breakers for the devices on the ebus? The lines will > be real short and it eliminates the single point of failure (breaker.) > Also, what about fuselinks? I understand them to be like a fuse that > blows extremely slowly, but I'm not fully understanding when and where > to use them. > > It's not clear that you've latched onto what > fuses and breakers are all about. I'll suggest > that you re-consider fuse blocks for ALL busses > and one fuse per accessory. Quick, light, easy > to install, and inexpensive. > I know that fuses/breakers/fuselinks protect the wiring, what I was missing was the part about problems with one component spreading to others instead of being isolated. I think I will just get fuse blocks per your recommendation for the reasons you mention, but also because problems with a fuse can be remedied in the air quickly and easily. Thanks again, schu ________________________________________________________________________________
Subject: Re: Adding an antenna to improve on the ground reception?
From: "edleg" <ed_legault(at)yahoo.com>
Date: Jan 01, 2010
You could use an antenna switch (vhf) to choose/select top or bottom antenna. Check with your local ham radio store, or do a "google" search for same. It would add maybe a pound or two to your comm installation with the switch, extra cabling and antenna. -Ed- KD6UBY Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279720#279720 ________________________________________________________________________________
From: "Rino" <lacombr(at)nbnet.nb.ca>
Subject:
Date: Jan 02, 2010
Ton voyage s'est bien pass=E9? Tout =E9tait correct =E0 ton appart? Bises, Rita ________________________________________________________________________________
From: <bakerocb(at)cox.net>
Subject: Issue with Garmin GTX 330 XPDR
Date: Jan 02, 2010
1/2/2010 Hello Don Morrisey, You wrote: "I later discovered that each time I activate the Master SWitch the unit turns itself on even though I had left it powered off via the "Off" button on the unit. I went back over the wiring and nothing seems amiss??? Any idea why it would be doing this?" This very topic is currently being discussed on the aeroelectric list. Read the email exchanges below (last email is first). Also if you go to this web site, download the GTX327 installation manual and look at figure B4 on page 47 you will see the pins and notes that are being discussed. http://www.velocityxl.com/Downloads/GTX327Transponder_InstallationManual.pdf OC ========================================== Allen then wrote: Actually I meant 327 rather than 337. I looked at the installation manual pin out diagram and my Approach Systems engineer (Tim Hass) has pin 1 and pin 15 jumpered. The drawing calls pin 1 "Avionics Master on which may be the pin that I could unhook from power and make it work like we want. I emailed Tim Hass at Approach Systems to ask for clarification on this issue. I'll let you know what I find out. Allen ================================================= -----Original Message----- From: bakerocb(at)cox.net [mailto:bakerocb(at)cox.net] Sent: Friday, January 01, 2010 1:22 PM Subject: GTX337 ON or OFF? 1/1/2010 Hello Allen Fullmer, You wrote: "........skip.....I have also noticed that the GTX337 transponder cannot be set to remain off when power is supplied. It will remain in the standby position but, once again, when I am playing and fiddling around I just hate to see it go up and down unnecessarily. Haven't decided on a switch for it or not." I also can not program my GTX327 to remain OFF when power is applied or reapplied to the avionics buss.** But the GTX327 has some options on which pins electrical power can be supplied to. If you pick the correct pin(s) the box will remain OFF until you push the ON button on the face of the box. I suspect that the GTX337 may be built the same way. So if you desire, and have the capability, you could rewire your GTX337 so that it would remain OFF until you pushed the ON button on the face of the box. 'OC' Says: "The best investment we can make is the effort to gather and understand knowledge." **PS: I suspect that the person who wired my panel set it up that way so that it would take a very deliberate OFF button action on my part in order to take off with the transponder OFF. I am with you, I'd like to have total ON - OFF control of the box with the buttons on the face of the box. 'OC' Says: "The best investment we can make is the effort to gather and understand knowledge." ============================================== From: Don Morrisey <donmorrisey(at)hotmail.com> Subject: Avionics-List: Issue with Garmin GTX 330 XPDR Hello Listers I have just been finishing up my panel and one of the last things in was my transponder a Garmin GTX 330 . Very straightforward to install as I had a wiring harness made for it. Anyway got it in and it powered right up and does a self test etc. I later discovered that each time I activate the Ma ster SWitch=2C the unit turns itself on=2C even though I had left it powere d off via the "Off" button on the unit. I went back over the wiring and no thing seems amiss??? Any idea why it would be doing this? I have no issues with any of my other avionics that are connected to this wiring harness (SL40 and PMA 4000 Audi o Panel). Thanks. Don... www.donsbushcaddy.com Don Morrisey's Skunkworks ________________________________________________________________________________
From: <bakerocb(at)cox.net>
Subject: Questions about circuit protection
Date: Jan 02, 2010
1/2/2010 Hello Matthew Schumacher, You wrote: "I think I will just get fuse blocks per your recommendation for the reasons you mention, but also because problems with a fuse can be remedied in the air quickly and easily." If you are thinking of replacing fuses in the air to trouble shoot and solve an electrical problem please think again. There are several disadvantages. Some are: 1) Your airplane's Operating Limitations (part of its airworthiness certificate) will require you to equip the aircraft in accordance with 14 CFR 91.205 if you fly at night or IFR. Paragraph 91.205 (c) (6) says: "One spare set of fuses, or three spare fuses of each kind required, that are accessible to the pilot in flight." This means that, by regulation, if you design your airplane so that you have access to those fuse blocks in flight then you must also have available to you all those spare fuses while in flight. Do you want to create that burden / nuisance / danger? 2) Trouble shooting an electrical system in flight by fumbling around to locate and then insert the appropriate fuse is not a good idea, particularly at night or IFR when you should be concentrating on flying the airplane. So fuse blocks are a good idea, but where you locate them has some operational and safety implications. Please read some more of Bob Nuckolls' philosophy regarding electrical problems / failures in flight. 'OC' Says: "The best investment we can make is the effort to gather and understand knowledge." ======================================================== From: Matthew Schumacher <schu(at)schu.net> Subject: Re: AeroElectric-List: Questions about circuit protection. First, thank you very much for looking at my stuff Bob. I greatly appreciate it and have donated to keep this list going... ...................................... big skip ...................................... I know that fuses/breakers/fuselinks protect the wiring, what I was missing was the part about problems with one component spreading to others instead of being isolated. I think I will just get fuse blocks per your recommendation for the reasons you mention, but also because problems with a fuse can be remedied in the air quickly and easily. Thanks again, schu ________________________________________________________________________________
Date: Jan 02, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Noise filter ?
>However, my second radio is on my main bus. Should I stick a diode >and capacitor in its feed line after the fuse ? Or should I plan >instead to rectifiy any noise issues if I actually have them ? My >anti-collision lights will be LEDs, not strobes, but I tend to think >clean power is good power. Jeff, I wouldn't strike out to solve a "noise" problem that has yet to manifest itself. Many moons ago a builder called me one night to describe how he had shielded the majority of his system's wiring, put off the shelf filters on all potential victims and antagonists and was calling to ask, "is there anything I've overlooked?" I had to ask, "Gee, how does your noise problem manifest itself?" "Oh," he replies, "I'm still building. The airplane hasn't flown yet." This is a tip-of-the-bell-curve example of how NOT to approach the design and fabrication of a new system in an airplane. Keep in mind that the majority of antagonist/victim accessories are DESIGNED with their target application in mind. We consider DO-160 EMC and MIL-STD-704 power studies that teach us how to LIVE with a certain amount of noise on the bus while LIMITING how much noise we allow to be generated on the bus. I've seen dozens of products offered like the ubiquitous "surge protection" devices for computers . . . except these are intended to ward off evil spirits and slay dragons that are reputed to live on your airplane's power system. I think I spoke about extra-ordinary prophylactic noise mitigation in the chapter on noise in the 'Connection. Once you've shielded p-leads and crafted single point grounds, your probability of noise problems goes down to a tiny fraction of what's possible. The guy who called me about his noise mitigation program expended many hours, dollars and several pounds of empty weight on a useless activity. I can tell you that tens of thousands of strobe systems (and other potentially noisy appliances) have been successfully integrated into both TC and OBAM aircraft with no noise dragons to slay. Put the stuff all together first using ground rules established by decades of lessons-learned and let's tackle a noise problem later. It's likely that it won't show up. Bob . . . Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ ________________________________________________________________________________
Date: Jan 02, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Questions about circuit protection.
> > > > Why not simply add a switch in series with your > > e-bus normal feed path diode and label it > > "Avionics Master". Then ditch the avionics bus > > and run your avionics of concern along with > > endurance necessities from the e-bus. > >It is my understanding that the purpose of the e-bus is to be able to >open the battery contactor and instantly have the system load drop to >whatever is on the e-bus making it easier and quicker for the pilot to >shed unneeded load in the event of an alternator failure. No. The E-bus is where you power things that are part of your Plan-B for sustained flight battery only. YOU decide what the E-hours are. If you plan to maintain the battery such that E-power-hours is equal to or less than battery capacity, great. If some smaller performance value meets your design goals, great. But DECIDE what those design goals are and craft the system to match. >To that end I put only required avionics on the e-bus and avionics that >I don't absolutely need to have on an avionics bus thinking that this >was in line with the design goals of using an e-bus. Since you have subscribed to the ill-conceived notion of an 'avionics bus' then the simple solution is to COMBINED the functionality of the A-bus with the E-Bus and add the switch in series with the normal feedpath diode. You don't need to add a special bus to coddle radios that don't need coddling. >So my question is this: Given that simple is always >cheaper/lighter/more reliable, is it worth the weight/cost/complexity to >add a bus and a switch so that I can keep my avionics off during start, >and be able to instantly shed all non-critical loads? I thought it was, >but it seems like you disagree. As described above, the only increase in complexity to meet your design goals for an A-bus is make the E-bus double up in that capacity. Alternatively, you can abandon the legacy prophylactic for an A-bus and associated master switch. See: >Also, what are others doing here? Are they simply using the built in >power switch to turn stuff off at start (if the component has a built in >switch.) The avionics master switch was never really necessary for the reasons imagined at the time it was created. I remember. I was working as a tech writer at Cessna when the AV master was conceived. I wrote sections of maintenance manuals that spoke to the perceived hoards of hazard lurked upon the bus waiting to pounce on fragile radios. See: http://www.aeroelectric.com/articles/avmaster.pdf http://www.aeroelectric.com/articles/spike.pdf http://www.aeroelectric.com/articles/Philosophy/Whats_all_this_DO160_Stuff_Anyhow.pdf Today, we know better. There's no value to be added by dedicating a specially protected bus to power radios. >I know that fuses/breakers/fuselinks protect the wiring, what I was >missing was the part about problems with one component spreading to >others instead of being isolated. I think I will just get fuse blocks >per your recommendation for the reasons you mention, but also because >problems with a fuse can be remedied in the air quickly and easily. As Bob suggested in his earlier post, you might like to review the philosophy of breakers vs. fuses and the value of crafting a system where there are no designed in nuisance trips of fuses and no single accessory is "critical" . . . i.e. a failure tolerant system Fuse blocks can be tucked away out of sight, out of reach and out of mind. You need only ONE breaker and that only if you're using crowbar ov protection. Otherwise, it can ALL be out of reach fuses. Bob . . . ________________________________________________________________________________
From: "Ralph & Maria Finch" <ralphmariafinch(at)gmail.com>
Subject: THE VIRTUE OF SIMPLICITY
Date: Jan 02, 2010
To play the part of the loyal opposition: Yes, but. Do any of us really want to depend on one of the old cars for daily transportation? I have memories, almost all bad, of the old clunkers. I love my modern autos, turn the switch and they start and run. Oil changes at greatly increased intervals, hardly any "tune-ups" and such. Our lives would be simpler without building airplanes, dealing with computers, and so forth. But by definition those reading this are doing those things and other non-simple chores and hobbies. To airplanes. Day VFR implies no lights, even no radios. Stay out of Class B and no transponder required. My build is delayed considerably by adding lights and such but I want them. I'll also have an EFIS and autopilot because I think they nice and a good convenience. These are, after all, experimental. Experiment as you wish. Let's just be aware of all the costs of adding equipment. BTW, I'm flying an Aircoupe now. When my RV-9A is finished I don't think I'll notice a few extra pounds in comparison...and besides, most of us Americans could easily make up for added equipment weight by losing our spare tires ;-) Ralph Finch Davis, California RV-9A QB-SA -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of racerjerry Sent: Friday, January 01, 2010 12:21 PM THE VIRTUE OF SIMPLICITY __________ Information from ESET Smart Security, version of virus signature database 4735 (20100101) __________ The message was checked by ESET Smart Security. ________________________________________________________________________________
Date: Jan 02, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: AeroElectric-List Digest: 17 Msgs - 01/01/10
At 11:07 AM 1/2/2010, you wrote: >Jerry, >All interesting information. >But, your assumption is that you are the only safety conscious one >on the forum and the rest of us are idiots. That simply is not the >case. (If you doubt this comment, then refer to your comments below >"I have a plan" and "overly complicated equipment and redundant >backup systems, much of which you barely understand.") >I wonder - why you think the rest of us are stupid? Gently my friend. Why do you take this as a personal attack? This is a forum for the exchange of ideas, crafting elegant design goals and the perfection of recipes for success. Please speak to ideas in the light of what I cited above. There's no reason for or value in pitching cabbages, tomatoes or rocks at each other. Bob . . . ________________________________________________________________________________
Date: Jan 02, 2010
From: Matthew Schumacher <schu(at)schu.net>
Subject: Re: Questions about circuit protection
bakerocb(at)cox.net wrote: > If you are thinking of replacing fuses in the air to trouble shoot and > solve an electrical problem please think again. There are several > disadvantages. Some are: > > 1) Your airplane's Operating Limitations (part of its airworthiness > certificate) will require you to equip the aircraft in accordance with > 14 CFR 91.205 if you fly at night or IFR. > > Paragraph 91.205 (c) (6) says: "One spare set of fuses, or three spare > fuses of each kind required, that are accessible to the pilot in flight." > > This means that, by regulation, if you design your airplane so that you > have access to those fuse blocks in flight then you must also have > available to you all those spare fuses while in flight. Do you want to > create that burden / nuisance / danger? Hold on, back the truck up. Are you saying that if I put the fuses under the panel where they aren't accessible then my airplane will still meet 14 CFR 91.205 (c) and that I won't need to carry spares? I would read "that are accessible to the pilot in flight" to mean that the fuse panel is accessible to the pilot, not the fusees since who cares if you can get to the fuses if you can't get to the panel. schu ________________________________________________________________________________
Date: Jan 02, 2010
From: Matthew Schumacher <schu(at)schu.net>
Subject: Re: Questions about circuit protection.
Robert L. Nuckolls, III wrote: > > Since you have subscribed to the ill-conceived notion > of an 'avionics bus' then the simple solution is > to COMBINED the functionality of the A-bus > with the E-Bus and add the switch in series with > the normal feedpath diode. You don't need to add > a special bus to coddle radios that don't need > coddling. > Thanks for taking the time to write all this out, I see where you are coming from now. schu ________________________________________________________________________________
From: jim-bean(at)att.net
Subject: Re: Adding an antenna to improve on the ground reception?
Date: Jan 02, 2010
________________________________________________________________________________
Date: Jan 02, 2010
Subject: Simplicity and circuit protection
From: Richard Girard <aslsa.rng(at)gmail.com>
The FAA has just released SAIB CE-10-11 "Electrical: Fire Hazard in Resetting Circuit Breakers" for operators of TC aircraft and transports, but the implications of it gives Bob's advice that much more teeth, IMHO. To summarize, the Feds are recommending that circuit breakers NOT be reset once they trip except under specific circumstances. The complete SAIB can be found here: https://www.faasafety.gov/files/notices/2009/Dec/SAIB_CE-10-11.pdf So, if you shouldn't reset them, what good are they? Rick Girard ________________________________________________________________________________
From: "Tim Andres" <tim2542(at)sbcglobal.net>
Subject: Questions about circuit protection.
Date: Jan 02, 2010
Hi Bob; I think some of us may be dealing with conflicting information from two respected sources, yourself and in some cases the manufacturers. Garmin and Grand Rapids for example specify their equipment to be off during starter engagement, the Grand Rapids units do not have an on/off switch and as we have recently learned the GTX 327 may not really be off just because you selected off, and the use of a "A" bus is mentioned in the install manual. So in Matt's defense it may not be his following an "ill conceived notion" as you mentioned, but a desire to serve two masters. Tim Andres -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Saturday, January 02, 2010 10:09 AM Subject: Re: AeroElectric-List: Questions about circuit protection. > > > > Why not simply add a switch in series with your > > e-bus normal feed path diode and label it > > "Avionics Master". Then ditch the avionics bus > > and run your avionics of concern along with > > endurance necessities from the e-bus. > >It is my understanding that the purpose of the e-bus is to be able to >open the battery contactor and instantly have the system load drop to >whatever is on the e-bus making it easier and quicker for the pilot to >shed unneeded load in the event of an alternator failure. No. The E-bus is where you power things that are part of your Plan-B for sustained flight battery only. YOU decide what the E-hours are. If you plan to maintain the battery such that E-power-hours is equal to or less than battery capacity, great. If some smaller performance value meets your design goals, great. But DECIDE what those design goals are and craft the system to match. >To that end I put only required avionics on the e-bus and avionics that >I don't absolutely need to have on an avionics bus thinking that this >was in line with the design goals of using an e-bus. Since you have subscribed to the ill-conceived notion of an 'avionics bus' then the simple solution is to COMBINED the functionality of the A-bus with the E-Bus and add the switch in series with the normal feedpath diode. You don't need to add a special bus to coddle radios that don't need coddling. >So my question is this: Given that simple is always >cheaper/lighter/more reliable, is it worth the weight/cost/complexity to >add a bus and a switch so that I can keep my avionics off during start, >and be able to instantly shed all non-critical loads? I thought it was, >but it seems like you disagree. As described above, the only increase in complexity to meet your design goals for an A-bus is make the E-bus double up in that capacity. Alternatively, you can abandon the legacy prophylactic for an A-bus and associated master switch. See: >Also, what are others doing here? Are they simply using the built in >power switch to turn stuff off at start (if the component has a built in >switch.) The avionics master switch was never really necessary for the reasons imagined at the time it was created. I remember. I was working as a tech writer at Cessna when the AV master was conceived. I wrote sections of maintenance manuals that spoke to the perceived hoards of hazard lurked upon the bus waiting to pounce on fragile radios. See: http://www.aeroelectric.com/articles/avmaster.pdf http://www.aeroelectric.com/articles/spike.pdf http://www.aeroelectric.com/articles/Philosophy/Whats_all_this_DO160_Stuff_A nyhow.pdf Today, we know better. There's no value to be added by dedicating a specially protected bus to power radios. >I know that fuses/breakers/fuselinks protect the wiring, what I was >missing was the part about problems with one component spreading to >others instead of being isolated. I think I will just get fuse blocks >per your recommendation for the reasons you mention, but also because >problems with a fuse can be remedied in the air quickly and easily. As Bob suggested in his earlier post, you might like to review the philosophy of breakers vs. fuses and the value of crafting a system where there are no designed in nuisance trips of fuses and no single accessory is "critical" . . . i.e. a failure tolerant system Fuse blocks can be tucked away out of sight, out of reach and out of mind. You need only ONE breaker and that only if you're using crowbar ov protection. Otherwise, it can ALL be out of reach fuses. Bob . . . ________________________________________________________________________________
From: "B Tomm" <fvalarm(at)rapidnet.net>
Subject: Simplicity and circuit protection
Date: Jan 02, 2010
"What good are they?" Easily reset (when back on the ground), easily pulled to disconnect during maintenance, or certain in-flight conditions. No fuses to buy and carry. Bevan _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Richard Girard Sent: Saturday, January 02, 2010 12:42 PM Subject: AeroElectric-List: Simplicity and circuit protection The FAA has just released SAIB CE-10-11 "Electrical: Fire Hazard in Resetting Circuit Breakers" for operators of TC aircraft and transports, but the implications of it gives Bob's advice that much more teeth, IMHO. To summarize, the Feds are recommending that circuit breakers NOT be reset once they trip except under specific circumstances. The complete SAIB can be found here: https://www.faasafety.gov/files/notices/2009/Dec/SAIB_CE-10-11.pdf So, if you shouldn't reset them, what good are they? Rick Girard ________________________________________________________________________________
Date: Jan 02, 2010
Subject: Re: Simplicity and circuit protection
From: Richard Girard <jindoguy(at)gmail.com>
Just my opinion but you can buy an awful lot of fuses for the price of a single C/B. As to being easily reset on the ground, that was exactly the condition that led to the crash that prompted the SAIB. Rick Girard On Sat, Jan 2, 2010 at 3:11 PM, B Tomm wrote: > "What good are they?" > > Easily reset (when back on the ground), easily pulled to disconnect during > maintenance, or certain in-flight conditions. No fuses to buy and carry. > > Bevan > > ------------------------------ > *From:* owner-aeroelectric-list-server(at)matronics.com [mailto: > owner-aeroelectric-list-server(at)matronics.com] *On Behalf Of *Richard > Girard > *Sent:* Saturday, January 02, 2010 12:42 PM > *To:* aeroelectric-list(at)matronics.com > *Subject:* AeroElectric-List: Simplicity and circuit protection > > The FAA has just released SAIB CE-10-11 "Electrical: Fire Hazard in > Resetting Circuit Breakers" for operators of TC aircraft and transports, > but the implications of it gives Bob's advice that much more teeth, IMHO. To > summarize, the Feds are recommending that circuit breakers NOT be reset once > they trip except under specific circumstances. The complete SAIB can be > found here: > > https://www.faasafety.gov/files/notices/2009/Dec/SAIB_CE-10-11.pdf > > So, if you shouldn't reset them, what good are they? > > Rick Girard > > * > > href="http://www.matronics.com/Navigator?AeroElectric-List">http://www.matronics.com/Navigator?AeroElectric-List > href="http://forums.matronics.com">http://forums.matronics.com > href="http://www.matronics.com/contribution">http://www.matronics.com/c* > > * > > * > > ________________________________________________________________________________
Subject: Re: Simplicity and circuit protection
From: "mmayfield" <mmayfield(at)ozemail.com.au>
Date: Jan 02, 2010
I've always agreed that breakers can be useful, but not because they can be reset after they automatically trip. On both the military aircraft and passenger jets I've flown, the most useful thing about circuit breakers was always: 1) the ability to manually trip them when smoke starts pouring out of a system which is still powered (happened once to a colleague of mine). 2) the ability to pull then reset non-tripped breakers, usually under engineering guidance, to get a glitchy system to restart itself. For 25 years in my experience, resetting an already tripped breaker was discouraged or prohibited by SOPs in most circumstances, ground or flight, until maintenance action was carried out. I'm not sure why this concept should be a surprise to anyone. Mike Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279823#279823 ________________________________________________________________________________
Subject: Z-14 Switch Combos
Date: Jan 02, 2010
From: "Perry, Phil" <Phil.Perry(at)netapp.com>
I'm getting a handle on Z-14 from an operational perspective and have a couple of questions about the switch combinations that could create issues. Obviously with the added complexity of managing two batteries, two alternators, and a cross feed can create some interesting combinations. Are there any combo's that we should be aware of that would create over voltage or any other scenarios of concern? In the event of a failure (for example Alt 2 failure), is there a specific order for shutting off the bad alt and then enabling the cross feed? Thanks, Phil ________________________________________________________________________________
From: "B Tomm" <fvalarm(at)rapidnet.net>
Subject: Simplicity and circuit protection
Date: Jan 02, 2010
>From my recollection of the account I read somewhere on-line, that circuit breaker was reset (on the ground) without any troubleshooting to determine why it tripped and what, if any, damage has been caused. If this person reset it in the air, there would be no difference in this case, other than the fire would have started sooner. The point I did not make clear is that to "reset when on the ground", to me means to troubleshoot that circuit, not just to push it back in and see if a fire starts. Breakers and fuses do not trip for no reason other than an over current event. The questions are, what caused the over current event, did this event cause any damage, and depending on those answers, is it likely to trip again if nothing else is done but to reset it? Bevan _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Richard Girard Sent: Saturday, January 02, 2010 2:13 PM Subject: Re: AeroElectric-List: Simplicity and circuit protection Just my opinion but you can buy an awful lot of fuses for the price of a single C/B. As to being easily reset on the ground, that was exactly the condition that led to the crash that prompted the SAIB. Rick Girard On Sat, Jan 2, 2010 at 3:11 PM, B Tomm wrote: "What good are they?" Easily reset (when back on the ground), easily pulled to disconnect during maintenance, or certain in-flight conditions. No fuses to buy and carry. Bevan _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Richard Girard Sent: Saturday, January 02, 2010 12:42 PM Subject: AeroElectric-List: Simplicity and circuit protection The FAA has just released SAIB CE-10-11 "Electrical: Fire Hazard in Resetting Circuit Breakers" for operators of TC aircraft and transports, but the implications of it gives Bob's advice that much more teeth, IMHO. To summarize, the Feds are recommending that circuit breakers NOT be reset once they trip except under specific circumstances. The complete SAIB can be found here: https://www.faasafety.gov/files/notices/2009/Dec/SAIB_CE-10-11.pdf So, if you shouldn't reset them, what good are they? Rick Girard href="http://www.matronics.com/Navigator?AeroElectric-List">http://www.matro nics.com/Navigator?AeroElectric-List href="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List tp://forums.matronics.com _blank">http://www.matronics.com/contribution ________________________________________________________________________________
Date: Jan 03, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Questions about circuit protection
> > >Hold on, back the truck up. Are you saying that if I put the fuses >under the panel where they aren't accessible then my airplane will still >meet 14 CFR 91.205 (c) and that I won't need to carry spares? > >I would read "that are accessible to the pilot in flight" to mean that >the fuse panel is accessible to the pilot, not the fusees since who >cares if you can get to the fuses if you can't get to the panel. First, 14 CFR 91.205 doesn't apply to an amateur built airplane. That's not to imply that the FARS don't have some things to be considered . . . but you have no obligation to consult these documents that apply to type certificated aircraft only. Further, 91.205 isn't the ONLY milestone at which your project is essentially "un-certifiable". But assume you adopt failure tolerance as a design goal. For every piece of equipment "critical" for the manner in which you plan to use the airplane, then that piece of equipment needs to be backed up with a plan-B. There are 100 times more failures in a piece of electronics that DOES NOT blow a fuse than there are failures that DO blow a fuse. If that piece of equipment is deemed critical, then having spare fuses for the circuit that supports that system is whistling in the dark. So assuming you have a back up for every POTENTIALLY critical system, then if follows that there are NO critical systems. Hence, whether or not you can reach breakers or fuses for any system is immaterial. Bob . . . ________________________________________________________________________________
From: "fox5flyer" <fox5flyer(at)idealwifi.net>
Subject: Duracells again...
Date: Jan 03, 2010
Yesterday, I was tinkering in my shop and when I attempted to use my analog volt meter, I found the needle would not swing across when I touched the leads together to calibrate it. Actually, the needle moved about one third of the way. As I hadn't changed the batteries in over a year I took the back off and low and behold I found a huge mess. Three of the four AA batteries had leaked all over the inside of the meter which effectively destroyed it as the resulting corrosion ruined the battery contact terminals. I've used this meter (Amprobe) for more than 30 years and it has never failed me, but now it is now in the trash. Never again with Duracells. Never... Deke ________________________________________________________________________________
Subject: Battery Bus Location
From: "PaulR" <prose(at)panhandle.rr.com>
Date: Jan 03, 2010
I'm working on locating items on the firewall and have a question on location of the alway hot battery bus. I know that there is a length limit on the wire powering this bus and with that in mind, it seems the ideal location for the fuse block is on the hot side of the firewall. Is this block and fuse combination okay to put on the hot side? Seems like it defeats the purpose of this bus if it's feeder line is fused and then put on the cool side of the firewall. Thanks -------- Paul Rose N417PR (res) RV-9A Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279865#279865 ________________________________________________________________________________
Date: Jan 03, 2010
From: Ron Quillin <rjquillin(at)gmail.com>
Subject: Re: Duracells again...
At 07:03 1/3/2010, you wrote: >Take it back out of the trash. box it up and ship to directly to >Duracell for a replacement. Several people have commented on this >list that Duracell will replace damaged items when their cells >leak.... Is this BS ? You can put this myth to bed for all of >us. If they really do replace stuff leaking cells damage then two >things will happen. Had a mouse with leaky Duracells in it, 'bout five years ago. Sent it in. As it was no longer a current model, I was sent a check for what they believed was it's replacement value. No hassle, other than the entire event. Ron Q. ________________________________________________________________________________
From: <bakerocb(at)cox.net>
Subject: Questions about circuit protection
Date: Jan 03, 2010
1/3/2009 Hello Again Matthew Schumacher, You wrote: 1) "Are you saying that if I put the fuses under the panel where they aren't accessible then my airplane will still meet 14 CFR 91.205 (c) and that I won't need to carry spares?" Yes. That is exactly what the regulation is saying. If the pilot does not have access, while in flight, to the location of fuses installed in the aircraft's electrical system then there is no 91.205 regulatory requirment to carry any spare fuses. 2) "I would read "that are accessible to the pilot in flight" to mean that the fuse panel is accessible to the pilot,......." That is correct. 3) "..........not the fusees since who cares if you can get to the fuses if you can't get to the panel." Again correct. Your reasoning, and the reasoning of the regulation, is that if you cannot get access to the location of the fuses installed in the electrical system while in flight then there is no reason for the pilot to carry, and have access to, spare fuses while in flight. Now the wise pilot would carry some spare fuses, as well as some other spare items or tools (which can be discussed at length), so that he may perform some limited trouble shooting / repair work if needed on the ground at some away from home location in order to get back to home base or some other location where he might be able to effect a more permanent repair. 'OC' Says: "The best investment we can make is the effort to gather and understand knowledge." PS: If one is designing and manufacturing a 14 CFR Part 23 type certificated aircraft the regulations / requirements for fuse location in the aircraft's electrical system are found in Part 23.1357 (d) which says: "If the ability to reset a circuit breaker or replace a fuse is essential to safety in flight, that circuit breaker or fuse must be so located and identified that it can be readily reset or replaced in flight." But experimental amateur built aircraft are not required, per se, to comply with 14 CFR Part 23. If we build our experimental amateur built aircraft's electrical system in accordance with the philosophy that things can fail and that we have a plan B back up that will allow graceful degradation and continued safe flight to an acceptable landing site then no fuse in our electrical system would be "essential to safety in flight". =================================================== From: Matthew Schumacher <schu(at)schu.net> Subject: Re: AeroElectric-List: Questions about circuit protection bakerocb(at)cox.net wrote: > If you are thinking of replacing fuses in the air to trouble shoot and > solve an electrical problem please think again. There are several > disadvantages. Some are: > > 1) Your airplane's Operating Limitations (part of its airworthiness > certificate) will require you to equip the aircraft in accordance with > 14 CFR 91.205 if you fly at night or IFR. > > Paragraph 91.205 (c) (6) says: "One spare set of fuses, or three spare > fuses of each kind required, that are accessible to the pilot in flight." > > This means that, by regulation, if you design your airplane so that you > have access to those fuse blocks in flight then you must also have > available to you all those spare fuses while in flight. Do you want to > create that burden / nuisance / danger? Hold on, back the truck up. Are you saying that if I put the fuses under the panel where they aren't accessible then my airplane will still meet 14 CFR 91.205 (c) and that I won't need to carry spares? I would read "that are accessible to the pilot in flight" to mean that the fuse panel is accessible to the pilot, not the fusees since who cares if you can get to the fuses if you can't get to the panel. schu ________________________________________________________________________________
Date: Jan 03, 2010
From: jerb <ulflyer(at)verizon.net>
Subject: Re: Duracells again...
Deke, The main reason I began using Durcell's long back is I could depend upon them not to leak in all my test and expensive equipment, they never leaked. This is why I raised the question if others were experiencing similar problems with them leaking. In the last few years I have observed an definite characteristic change of the Duracell product. I might expect a very old battery to leak a little if left for years, but my experience with them is a definite change where their leaking in short period and without being fully discharged. Thanks for everyone's feedback, guess it's time for me to send a letter and some leakers to P&G and see what their response is. jerb At 05:18 AM 1/3/2010, you wrote: >Yesterday, I was tinkering in my shop and when I attempted to use my >analog volt meter, I found the needle would not swing across when I >touched the leads together to calibrate it. Actually, the needle >moved about one third of the way. As I hadn't changed the batteries >in over a year I took the back off and low and behold I found a huge >mess. Three of the four AA batteries had leaked all over the inside >of the meter which effectively destroyed it as the resulting >corrosion ruined the battery contact terminals. I've used this >meter (Amprobe) for more than 30 years and it has never failed me, >but now it is now in the trash. >Never again with Duracells. Never... >Deke > > ________________________________________________________________________________
From: jim-bean(at)att.net
Subject: Re: Adding an antenna to improve on the ground reception?
Date: Jan 03, 2010
Problem: On the ground at KAWO (non-towered airport) I can't get Seattle Center (and my IFR clearance) because of my RV-8 belly-mounted comm antenna. (In a high wing trainer, this is not a problem.) I have a bubble canopy--can I add an antenna within my canopy to the existing belly antenna with a combiner/splitter to my comm receiver and achieve better reception on the ground without degrading my in the air reception/transmission? Ground plane problem with this setup? I can't easily place another antenna on the top fuselage. Suggestions? Don Schmiesing I have an antenna on my RV-8 slider which works pretty well. It is on the number 2 comm. I riveted an aluminum sheet to the aft end of the slider for a ground plane. The cable goes to the front of the slider. The front of the slider is about as far in front of the shoulder harness bracket when closed as it is in back of it when open, so a loop from the slider to the bracket works well. The whip goes through the canopy with a rubber grommet. I have some pictures but they won't get through the list. Jim Bean ________________________________________________________________________________
Date: Jan 03, 2010
From: John Markey <markeypilot(at)yahoo.com>
Subject: Max Alternator Voltage ?
We just returned from a 1.4 hour flight- @ 0'F conditions. it some cranking on the ramps at both ends of the flight legs to get going. Upon returning, I noticed 15.1 volts @ about 2-3 amps indicated. Is this OK for a 60-A alternator? What should be a max voltage under such circumstances before I have my EIS gives me an alarm? [user programmable value in the Grand Rapids unit] Thanks in advance, John in the Glasiar Deep peace of the Light of the World to you. -------- ------------------------- ---------------- --A Gaelic Blessing =0A=0A=0A ________________________________________________________________________________
Date: Jan 03, 2010
From: Ron Quillin <rjquillin(at)gmail.com>
Subject: Re: Max Alternator Voltage ?
At 14:09 1/3/2010, you wrote: >We just returned from a 1.4 hour flight @ 0'F conditions. >it some cranking on the ramps at both ends of the flight legs to get going. >Upon returning, I noticed 15.1 volts @ about 2-3 amps indicated. > >Is this OK for a 60-A alternator? >What should be a max voltage under such circumstances before I have >my EIS gives me an alarm? [user programmable value in the Grand Rapids unit] John, You may want to consult your battery manufacturers' site for the ICAW sheet and owners manual. In the TC world both Concorde and Gill have recommended charge voltages for their different battery types (flooded, AGM/VRGA) based on ambient temperatures. This has been the topic of some lively discussions here on the list before you could find with an archive search. A chart in the Concorde manual suggests, for 0F/-18C a voltage of ~ 15.5 volts. Ron Q. ________________________________________________________________________________
Subject: Re: Adding an antenna to improve on the ground reception?
From: "al38kit" <alfranken(at)msn.com>
Date: Jan 03, 2010
Put one radio on the new antenna that points up. Forget about the switch. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=279954#279954 ________________________________________________________________________________
Date: Jan 03, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Max Alternator Voltage ?
At 04:09 PM 1/3/2010, you wrote: We just returned from a 1.4 hour flight @ 0'F conditions. it some cranking on the ramps at both ends of the flight legs to get going. Upon returning, I noticed 15.1 volts @ about 2-3 amps indicated. Is this OK for a 60-A alternator? We'd like to see it a tad lower but it's not a crisis either. I ran an alternator in my GMC van for years at 15.2 volts which didn't seem to be particularly abusive of the battery either. What should be a max voltage under such circumstances before I have my EIS gives me an alarm? [user programmable value in the Grand Rapids unit] Trip calibration points for most OV protection systems is 16.2 +/-.2 volts. Get a second opinion from another known good voltmeter . . . a John Fluke instrument comes to mind as one potential 'gold standard'. If the bus is REALLY running that hot, it would probably be a good idea to do something to reduce it. What kind of regulator are you running? Bob . . . ________________________________________________________________________________
From: "Jeffrey W. Skiba" <jskiba(at)icosa.net>
Subject: =?us-ascii?Q?Question_about_16V_POLYFUSER_Radial_Leaded_Resettable_PTC_Av?=
=?us-ascii?Q?ailable_at_Digi-Key?
Date: Jan 03, 2010
I just noticed these at digikey web site as a new product.. Looks like one could use these instead of fuses or the traditional circuit breakers (for the average range of protection) But my question is do these trip the same as typical fuses ? I know they can reset but would it work like a fuse for time to trip or protection of the wire ? Catalog page: http://media.digikey.com/pdf/New%20Cat%20Page/101/Littelfuse/Polyfuse%20PTC% 20Reset%20Devices.pdf Here is a link to the Data sheet http://www.littelfuse.com/data/en/Data_Sheets/Littelfuse_PTC_16R.pdf it looks like they are used in a max volts of 16v (good, my system runs at 13.8 volts) and they have ones that range from: 2.5a to 14a Price looks cheap Light weight Small in size Other thoughts - comments - concerns ? Thanks Jeff ________________________________________________________________________________
From: "David LLoyd" <skywagon(at)charter.net>
Subject: Re: Max Alternator Voltage ?
Date: Jan 03, 2010
John, A proper voltage regulator, whether mechanical or solid state, has temperature compensation built in. The lower the ambient temperature the higher the charging voltage allowed from the alternator. Essentially, the colder the battery, the higher the charging voltage must be to get the proper chemical reaction with in the battery. In really hot weather, you will see the reverse; could see the charging voltage drop to under 13 volts. ----- Original Message ----- From: Ron Quillin To: aeroelectric-list(at)matronics.com Sent: Sunday, January 03, 2010 4:37 PM Subject: Re: AeroElectric-List: Max Alternator Voltage ? At 14:09 1/3/2010, you wrote: We just returned from a 1.4 hour flight @ 0'F conditions. it some cranking on the ramps at both ends of the flight legs to get going. Upon returning, I noticed 15.1 volts @ about 2-3 amps indicated. Is this OK for a 60-A alternator? What should be a max voltage under such circumstances before I have my EIS gives me an alarm? [user programmable value in the Grand Rapids unit] John, You may want to consult your battery manufacturers' site for the ICAW sheet and owners manual. In the TC world both Concorde and Gill have recommended charge voltages for their different battery types (flooded, AGM/VRGA) based on ambient temperatures. This has been the topic of some lively discussions here on the list before you could find with an archive search. A chart in the Concorde manual suggests, for 0F/-18C a voltage of ~ 15.5 volts. Ron Q. ________________________________________________________________________________
Date: Jan 03, 2010
From: Ron Quillin <rjquillin(at)gmail.com>
Subject: Re: Question about 16V POLYFUSER Radial Leaded Resettable
PTC Available at Digi-Key At 19:41 1/3/2010, you wrote: >Looks like one could use these instead of fuses or the traditional >circuit breakers (for the average range of protection) > >But my question is do these trip the same as typical fuses ? I know >they can reset but would it work like a fuse for time to trip or >protection of the wire ? Are we sure we want a device that can reset itself? Doesn't that pretty much violate the premise of not resetting a tripped breaker? http://www.littelfuse.com/design/literature/fuse-vs-ptc/resettable-ptcs.html ________________________________________________________________________________
Subject: Re: Duracells again...
From: "n395v" <Bearcat(at)bearcataviation.com>
Date: Jan 04, 2010
> Is this BS ? You can put this myth to bed for all of us. If they really do replace stuff leaking cells damage then two things will happen. > 1- They will replace all items damaged, fix their manufacturing process and go on the be a premier battery seller. > 2- They will go out of business for cramming crap down our throats. > Marketplace, and its side effects are a wonderful thing ya know. > A couple of data points to ponder. I suspect the reason we see primarily Duracell quality being complained about is the fact that they probably supply 70% of the alkaline batteries that we use. I once worked for Duracell and it is amazing to see how they are made at high speed. They go through the line so fast that it is hard to see even with the fastest strobe. Given the noxious chemicals that they are made from it is amazing they do not start leaking day 1. All of them are rigorously tested for leakage before shipment after several weeks of storage and aging. Duracell has always had a policy (and has always honored it) of replacing or compensating for any damage their batteries cause. They even honored this policy when the customer has left the batteries in their camera, etc. for 10 years. This pretty much no questions asked policy is the benefit of paying a bit more for a Duracell. As to the el cheapos being a better deal( as in cheaper, longer life, less leakage)........ With the exception of Eveready I have watched pretty much every other brand of alkaline battery run down the assembly lines at the Duracell factory. This includes Ray O Vac and many of the brands mentioned in several of the battery life studies. My guess is when you buy any alkaline battery other than Eveready you are assuming a 50-60% probability that it came down the same assembly line as the Duracell you replaced with it. Only difference is that the marketers of the el cheapo ain't gonna replace your mag lite when it leaks. Given the billions of batteries sold the number of leakers that leak within the expected battery life is miniscule. It just seems like a lot when it gets our favorite maglite. -------- Milt Read this topic online here: http://forums.matronics.com/viewtopic.php?p=280022#280022 ________________________________________________________________________________
Subject: Re: Z-14 Switch Combos
From: "bcondrey" <bob.condrey(at)baesystems.com>
Date: Jan 04, 2010
Phil, There isn't anything bad that will happen regardless of switch positions for Z-14 as depicted in the stock diagrams. You've got 2 bus power switches and either can be on or off irrespective of the other (they are isolated). Further, the x-feed switch can be on even if both alternators are online with no ill effect (at least with B&C externally regulated devices). Bob RV-10 N442PM (flying with Z-14) Read this topic online here: http://forums.matronics.com/viewtopic.php?p=280027#280027 ________________________________________________________________________________
Subject: Re: Question about 16V POLYFUSER Radial Leaded Resettable
PTC Available at Digi-Key
From: Ian <ixb(at)videotron.ca>
Date: Jan 04, 2010
This is the same technology as used in the EXP2BUS. It's what attracted me to that device and it seems to work well. I have had an occasion where one circuit has tripped and reset itself after having been unloaded for a few seconds. Of course that doesn't remove the necessity to find out why the circuit tripped in the first place, and in general circuit boards tend to need to stay cleaner, and cooler than circuit breakers and switches. I found the price was about the same, when you compare the cost of ten or so circuit breakers and ten switches etc. to the bare board version. http://www.aircraftspruce.com/catalog/elpages/expbus.php But I'd have to say that, to do it all again, I'd go with a vanilla version of one of Mr. Nuckolls designs, with circuit breakers and switches. Ian Brown, Bromont, Quebec -----Original Message----- From: Jeffrey W. Skiba <jskiba(at)icosa.net> Subject: AeroElectric-List: Question about 16V POLYFUSER Radial Leaded Resettable PTC Available at Digi-Key Date: Sun, 03 Jan 2010 21:41:04 -0600 But my question is do these trip the same as typical fuses ? I know they can reset but would it work like a fuse for time to trip or protection of the wire ? ________________________________________________________________________________
Subject: Re: Questions about circuit protection
From: "user9253" <fran4sew(at)banyanol.com>
Date: Jan 04, 2010
Schu, No switch is shown for the Hobbs meter. I assume that an oil pressure switch will be connected in series with it. The diode across the E-Bus relay is backwards. The spike protection diode is missing from the dynamo relay coil. The arrow should point towards positive. No over-voltage protection is shown for the main alternator. Over-voltage protection will do more towards safeguarding avionics than an avionics master switch. Since there are only two devices connected to the avionics bus, an avionics bus is not needed. Just connect those two devices to the switch without having a bus. Better yet, use two switches. If one of the devices starts smoking, you can shut it off and continue to use the other. Wire the E-Bus diode directly to the main power bus without a switch. An avionics master switch makes it convenient to shut off all of the avionics at once. But when it fails, so will everything connected to it. In addition, individual downstream switches will not get exercised, leading to corrosion and eventual failure of seldom used switches. Fuses offer better protection than circuit breakers. And fuses are less expensive. Yes, more than one load can be connected to a fuse or circuit breaker. But if one of the loads shorts out, it will blow the fuse and remove power from the other loads. It is better to install a larger fuse block so that each load can have its own fuse. Regulations for type certificated aircraft require that critical fuses be replaceable in flight. However, it is better not to have any critical equipment. Backup equipment makes critical devices non-critical. Fuses should be replaced on the ground, not in the air. I like your schematic. What program do you use to draw it and to convert it a pdf? Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=280034#280034 ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Question about 16V POLYFUSER Radial Leaded Resettable
PTC Available at Digi-Key At 09:41 PM 1/3/2010, you wrote: >I just noticed these at digikey web site as a new product=85. > >Looks like one could use these instead of fuses >or the traditional circuit breakers (for the average range of protection) > >But my question is do these trip the same as >typical fuses ? I know they can reset but would >it work like a fuse for time to trip or protection of the wire ? > >Catalog page: ><http://media.digikey.com/pdf/New%20Cat%20Page/101/Littelfuse/Polyfuse%20PT C%20Reset%20Devices.pdf>http://media.digikey.com/pdf/New%20Cat%20Page/101/Li ttelfuse/Polyfuse%20PTC%20Reset%20Devices.pdf > > >Here is a link to the Data sheet > ><http://www.littelfuse.com/data/en/Data_Sheets/Littelfuse_PTC_16R.pdf>http: //www.littelfuse.com/data/en/Data_Sheets/Littelfuse_PTC_16R.pdf > >it looks like they are used in a max volts of >16v (good, my system runs at 13.8 volts) > >and they have ones that range from: 2.5a to 14a > > >Price looks cheap > >Light weight > >Small in size > >Other thoughts ' comments ' concerns ? > >Thanks > >Jeff > Go to http://tinyurl.com/yzs2u65 and review the discussions on Exp Bus and Greg Richter's polyswitch based products. The polyfuse has been around for 30+ years. We looked at them for general circuit protection in the GP-180 program at Lear. We looked at them at least twice that I know of at Beech/Ratheon/ Hawker-Beech. In no instance were we able to integrate these products into either legacy or current design goals for TC aircraft. These devices are intended for integration inside a product where their unique issues of wiring (20AWG solid wires soldered to ECB), mounting for vibration resistance, self-resetting, etc could be smoothly integrated into the product. None of the studies lasted more than a couple of days before we agreed that they're fine in a clock radio or toaster . . . or even some automotive applications. My cars use poly-fuses in series with the window lift motors. They are used in lieu of limit switches for actuator travel. In this case, the lift mechanism hits a hard mechanical stop at travel limits whereupon you are expected to release the switch. But if you continue to hold the switch for say 30 seconds. You'll find that the motor mysteriously goes dead. You'll have to wait a minute or two for the polyswitch to cool off before the system ops return to nomral. Interestingly enough, the polyswitch does not protect the window lift motor feeders from the bus. There's still a fuse in that slot. They're a fine product and perform as advertised in gazillions of situations. But they were never intended for and do not integrate well into general protection of power distribution feeders off a bus. This is especially true of aircraft when the owner-operator wants to be aware of any fault that generates a trip so that the difficulty can be accommodated (plan b) and fixed on the ground. The only instances I've observed attempts to pull this off are on EXP-Bus and on Richter's proposed product described in the articles cited in the above literature search. Bob . . . ________________________________________________________________________________
From: "fox5flyer" <fox5flyer(at)idealwifi.net>
Subject: Re: Duracells again...
Date: Jan 04, 2010
Thanks for the feedback, Bob. That old volt meter was a good one and had sentimental value. It's still in my workshop trash can so I think I'll send it in to see what happens. It will only cost me the price of postage. Can you point me to a link at Duracell that addresses this return procedure? Deke ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Duracells again...
>With the exception of Eveready I have watched pretty much every >other brand of alkaline battery run down the assembly lines at the >Duracell factory. This includes Ray O Vac and many of the brands >mentioned in several of the battery life studies. My guess is when >you buy any alkaline battery other than Eveready you are assuming a >50-60% probability that it came down the same assembly line as the >Duracell you replaced with it. Only difference is that the >marketers of the el cheapo ain't gonna replace your mag lite when it leaks. > >Given the billions of batteries sold the number of leakers that leak >within the expected battery life is miniscule. It just seems like a >lot when it gets our favorite maglite. Milt. Thank you so much for your insight on this topic. A similar discussion on battery contactors came up many years ago . . . don't recall if it was Compuserve AVSIG or here on this List. Folks were bad-mouthing the el-cheeso contactors that I was selling which were descendants of the RBM Controls that put batteries into the first S.E. TC aircraft back in the 40s. Ask any mechanic how many of these contactors . . . http://www.aeroelectric.com/Pictures/Contactors/s701-1l.jpg are replaced in comparison to these contactors . . . http://www.aeroelectric.com/Pictures/Contactors/6041_Contactor.jpg and they universally state . . . "Oh man! We replace those tin cans 10x more often than the gold plated ones." What's seldom asked and answered or even investigated is what are the flight hours on both styles of device when replacement is made . . . and what is the fielded population of both contactors? I'm certain that in the big picture, the el-cheeso contactor does not suffer failure rates so great that one is encouraged to replace it with a device that costs 10x as much. It's a matter of cost of ownership versus risk in a marketplace so large that perfectly ordinary failure rates make the el-cheeso contactor look like trash. I've suspected . . . and your own observations confirm . . . that the Duracell folks who buy $millions$ in VERY effective advertising are suffering from success. Their market penetration is so huge (like comparing Cessna+Piper versus Beech+Mooney) that taking a telescopic, narrow view of failure rates will yield distorted perceptions. We've had similar discussions on $value$ of various brands of alternators . . . particularly those that are artfully re-manufactured. I visited a reman operation in California/Mexico a year or so ago. Once a particular brand of alternator passes through a MPA facility, it's now an MPA part no matter who manufactured it originally. When I asked the chief engineer at MPA, "Who makes the best stock alternator?", he admitted to not having a clue. He said something to the effect, "We do the best we know how to do on every part that passes through our facility. Once it leaves here, it's OUR part. We don't see any extra-ordinary failure rates that can be attributed to the original manufacturers. So I cannot tell you nor would I even care who is king-of-the-hill for new parts. My job is to make every MPA product worthy of our customer's branding . . . of which there are DOZENS." I suspect that an artfully crafted study of the alkaline battery market would produce similar revelations. Thanks for sharing. Bob . . . ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Z-14 Switch Combos
At 10:00 AM 1/4/2010, you wrote: > > >Phil, > >There isn't anything bad that will happen regardless of switch >positions for Z-14 as depicted in the stock diagrams. You've got 2 >bus power switches and either can be on or off irrespective of the >other (they are isolated). Further, the x-feed switch can be on >even if both alternators are online with no ill effect (at least >with B&C externally regulated devices). There are no "gotchas" lurking in the design or operation of Figure Z-14 . . . nothing is at risk for damage due to mis-positioning of switches. Bob . . . ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Questions about circuit protection
>Wire the E-Bus diode directly to the main power bus without a >switch. An avionics master switch makes it convenient to shut off >all of the avionics at once. But when it fails, so will everything >connected to it. In addition, individual downstream switches will >not get exercised, leading to corrosion and eventual failure of >seldom used switches. True with one minor exception. Assuming one adds an "avionics master switch" in series with the normal feed path diode, it's still backed up by the alternate feed path switch. So its addition doesn't offer an increased risk for loss of the bus. Both the AV master and E-bus Alt Feed switches will get operated once per flight cycle as a part of pre-flight . . . so corrosion from dis-use is not a concern either. Otherwise . . . well stated sir. Bob . . . ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Max Alternator Voltage ?
At 10:28 PM 1/3/2010, you wrote: >John, >A proper voltage regulator, whether mechanical or solid state, has >temperature compensation built in. The lower the ambient >temperature the higher the charging voltage allowed from the >alternator. Essentially, the colder the battery, the higher the >charging voltage must be to get the proper chemical reaction with in >the battery. In really hot weather, you will see the reverse; could >see the charging voltage drop to under 13 volts. We used to see temperature compensation of regulators when they were external to the alternator. Even the old electro-mechanical generator regulators had bi-metal springs to stiffen the spring rate at cold temps. As soon as the regulators moved inside the alternator, the regulator's sense of battery environment was clouded by alternator heating. We considered built in compensation on the B&C regulators and rejected the idea as greater potential for problems than potential for benefit. I suspect that the phenomenon Ron is reporting has more to do with a regulator problem than an expected reaction to temperature. Bob . . . ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Questions about circuit protection.
At 03:01 PM 1/2/2010, you wrote: > >Hi Bob; > >I think some of us may be dealing with conflicting information from two >respected sources, yourself and in some cases the manufacturers. Garmin and >Grand Rapids for example specify their equipment to be off during starter >engagement, the Grand Rapids units do not have an on/off switch and as we >have recently learned the GTX 327 may not really be off just because you >selected off, and the use of a "A" bus is mentioned in the install manual. >So in Matt's defense it may not be his following an "ill conceived notion" >as you mentioned, but a desire to serve two masters. It's an unfortunate condition of our culture that so many exceedingly talented and capable suppliers of products are so ignorant of the environment to which they market. There's a mountain of analysis, laboratory and field testing that promulgated DO-160 and Mil-Std-704 along with a host of other design guides for DC electrical systems. At the same time, the "starter spike" bug-a-boo is one of those deeply held beliefs that is simply not supported by data. Nevertheless, manufacturers of devices with transistors in them seem to embrace some sort of fragility in their own products after they spent buckets of money to certify them into the type-certificated aircraft environment. I have designed dozens of products and put my hands on hundreds more that were just as complex and potentially 'fragile' as the panel mounted radios . . . yet NONE of these manufacturers suggest that the pilot pull a breaker on the device while cranking the engine. Somehow, as soon as the electro-whizzy is mounted to the panel where the pilot can see it . . . it's suddenly worthy of special protection from a risk that (1) doesn't exist and (2) the product has been demonstrated to withstand even if it did exist. I'll invite anyone on the list to contact the manufacturer of any product where the operating manual calls for turning it off during cranking. Ask them to identify the waveform, magnitude and duration of any cranking transient that exceeds their DO-160 certification testing. I've done this many times over 30 years. I've never had a lucid defense of the idea. In a few cases (King and Terra) the guy said, "yeah, it's all B.S. . . . but we've been doing it for decades and nobody wants to change it. So I leave it up to you. If adding a switch to the normal feed path diode makes you feel better, by all means do it. It doesn't add risk because the alternate feed path switch backs it up. Bob . . . ________________________________________________________________________________
Date: Jan 04, 2010
From: Bill Mauledriver Watson <MauleDriver(at)nc.rr.com>
Subject: Re: Z-14 Switch Combos
Phil, that's been my understanding too but I have no actual experience. Bob C. here knows what he's talking about. Bill bcondrey wrote: > > Phil, > > There isn't anything bad that will happen regardless of switch positions for Z-14 as depicted in the stock diagrams. You've got 2 bus power switches and either can be on or off irrespective of the other (they are isolated). Further, the x-feed switch can be on even if both alternators are online with no ill effect (at least with B&C externally regulated devices). > > Bob > RV-10 N442PM (flying with Z-14) > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=280027#280027 > > > ________________________________________________________________________________
Date: Jan 04, 2010
From: Matthew Schumacher <schu(at)schu.net>
Subject: Re: Questions about circuit protection
user9253 wrote: > > Schu, > > No switch is shown for the Hobbs meter. I assume that an oil pressure switch will be connected in series with it. > > The diode across the E-Bus relay is backwards. > > The spike protection diode is missing from the dynamo relay coil. The arrow should point towards positive. > > No over-voltage protection is shown for the main alternator. Over-voltage protection will do more towards safeguarding avionics than an avionics master switch. > > Since there are only two devices connected to the avionics bus, an avionics bus is not needed. Just connect those two devices to the switch without having a bus. Better yet, use two switches. If one of the devices starts smoking, you can shut it off and continue to use the other. Wire the E-Bus diode directly to the main power bus without a switch. An avionics master switch makes it convenient to shut off all of the avionics at once. But when it fails, so will everything connected to it. In addition, individual downstream switches will not get exercised, leading to corrosion and eventual failure of seldom used switches. > > Fuses offer better protection than circuit breakers. And fuses are less expensive. Yes, more than one load can be connected to a fuse or circuit breaker. But if one of the loads shorts out, it will blow the fuse and remove power from the other loads. It is better to install a larger fuse block so that each load can have its own fuse. Regulations for type certificated aircraft require that critical fuses be replaceable in flight. However, it is better not to have any critical equipment. Backup equipment makes critical devices non-critical. Fuses should be replaced on the ground, not in the air. > > I like your schematic. What program do you use to draw it and to convert it a pdf? > > Joe > > Joe, Thanks for your helpful comments. I would like to get an oil pressure switch for the hobbs (and for an idiot light) but I don't know where to source that. I looked around at Aircraft Spruce but didn't find anything. Do you know where I can find this? Thanks for finding the diode issues. I'll correct them in the drawing. There is over voltage protection internal to the main alternator since it is a plane power unit. The schematic was written in visio with the aeroelectric stencil set: http://www.lucubration.com/open-source-projects/aeroelectric-visio-symbols.html Converting to pdf is a little bit more involved but not bad (right Tim?). Simply install any postscript compatible printer (I like the apple color laser PS models), then tell windows that the port used is "save as file." When you print to that printer then it will prompt you for a file name, call the file drawing.ps or whatever, then use a postscript to pdf converter to make the pdf. A free online one is http://ps2pdf.com . The advantage to doing it this way is postscript is a vector based image not raster. This means that it isn't a 'picture' as much as a set of points what the printer fills in (not unlike a cad file.) This is why the file size is so small and why you can zoom in as close as you want and the edges are still sharp. The pdf viewer can re-render the image at any ratio. Clear as mud? schu ________________________________________________________________________________
Date: Jan 04, 2010
From: Matthew Schumacher <schu(at)schu.net>
Subject: Re: Questions about circuit protection.
Robert L. Nuckolls, III wrote: > I'll invite anyone on the list to contact the > manufacturer of any product where the operating > manual calls for turning it off during cranking. > Ask them to identify the waveform, magnitude > and duration of any cranking transient that > exceeds their DO-160 certification testing. Are the experimental avionics from Advanced Flight Systems, TruTrak Flight Systems, Dynon Avionics, and Grand Rapids certified to DO-160? I'm running the AFS box and don't see anything in the manual about starting, but I do see this: "All aircraft must have protection diodes installed on their Master Relay, Starter Relay and any other large relay. If your aircraft does not have the protection diode on the Master Relay your electrical buss will experience a voltage spike of 500+ Volts every time you turn off the master switch. If your EFIS or Engine Monitor is wired directly to the electrical buss it will be the device that absorbs the voltage spike and will eventually fail. All users must verify that they have the protection diodes installed before powering the EFIS or Engine Monitor." schu ________________________________________________________________________________
From: Etienne Phillips <etienne.phillips(at)gmail.com>
Subject: Re: Question about 16V POLYFUSER Radial Leaded Resettable
PTC Available at Digi-Key
Date: Jan 04, 2010
Hi Jeff I designed and have been using an electrical system similar to the EXP bus for over a year, for no reason other than experimentation. I chose a variety of these, ranging from 1A up to 16A... They work as advertised, and have found their trip performance similar to that of CB's, i.e. a 2A polyswitch probably won't trip at 2A, unless the device draws 2A for minutes almost. 2.5A will trip after a few seconds, 5A will trip after a second, and 100A will trip almost instantaneously. However, as has been mentioned by a fellow respondent, if your downstream device is something like an EFIS, or a device with an intelligent power supply that turns off when the supply voltage drops below a threshold, the polyswitch will probably reset itself, as the current draw that it sees goes to 0A and it cools down. To fix this, you need to add a dummy load with enough current flowing through it to keep the polyswitch tripped until you cycle the power to it manually. As soon as you start adding in this functionality, you need to start weighing up the added complexity of many failure-prone components, on one failure-prone fiberglass sheet, with micron-thick failure-prone copper tracking, against a couple robust tefzel wires crimped and bolted onto a robust CB... As an electrical engineer (yes, I've been following the Engineers in the real-world discussion!) and I'm a fan of blinking lights and push buttons when it affords me the opportunity to get some experience designing something more complex than a matchbox. However I fly VFR by day only and have complete steam backup and a handheld radio, so if I lose all electrics, it has no impact on my ability to complete the flight safely and with no discomfort. So to answer your questions, yes I think they can replace CB's or standard fuses, but I don't think they should. The fact that they reset themselves whenever power is cycled means that a tripped system will not stay tripped if you turn off the master switch. Standard fuses are much better-suited to the task. And that's in my humble opinion ;-) Thanks Etienne On 04 Jan 2010, at 5:41 AM, Jeffrey W. Skiba wrote: > I just noticed these at digikey web site as a new product=85. > > Looks like one could use these instead of fuses or the traditional > circuit breakers (for the average range of protection) > > But my question is do these trip the same as typical fuses ? I know > they can reset but would it work like a fuse for time to trip or > protection of the wire ? > > Catalog page: > http://media.digikey.com/pdf/New%20Cat%20Page/101/Littelfuse/Polyfuse%20PT C%20Reset%20Devices.pdf > > > Here is a link to the Data sheet > > http://www.littelfuse.com/data/en/Data_Sheets/Littelfuse_PTC_16R.pdf > > it looks like they are used in a max volts of 16v (good, my system > runs at 13.8 volts) > > and they have ones that range from: 2.5a to 14a > > > Price looks cheap > > Light weight > > Small in size > > Other thoughts ' comments ' concerns ? > > Thanks > > Jeff > > ________________________________________________________________________________
Date: Jan 04, 2010
From: Matthew Schumacher <schu(at)schu.net>
Subject: Re: Questions about circuit protection
user9253 wrote: > The spike protection diode is missing from the dynamo relay coil. The arrow should point towards positive. Joe, I looked at the dynamo relay coil but it is wired exactly as shown in Z-25 and Z-13/8. Bob, I would be very grateful if you could explain what the two diodes are for on the self exciting SD-8 drawing since since they are wired differently than the other relays. Thanks, schu ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Simplicity and circuit protection
At 07:16 PM 1/2/2010, you wrote: I've always agreed that breakers can be useful, but not because they can be reset after they automatically trip. On both the military aircraft and passenger jets I've flown, the most useful thing about circuit breakers was always: 1) the ability to manually trip them when smoke starts pouring out of a system which is still powered (happened once to a colleague of mine). Certainly possible but exceedingly low risk. It also presumes the pilot can identify the specific system. 2) the ability to pull then reset non-tripped breakers, usually under engineering guidance, to get a glitchy system to restart itself. Not unusual in a revenue generating environment manned by professionals. But after a couple of "glitches" in my OBAM aircraft electro-whizzy, I think I'd be sending it back to the factory for a fix or my money back. For 25 years in my experience, resetting an already tripped breaker was discouraged or prohibited by SOPs in most circumstances, ground or flight, until maintenance action was carried out. I'm not sure why this concept should be a surprise to anyone. Just read the dark-n-stormy night stories offered in the so-called aviation education journals. When electrical systems issues are part of story, there's plenty of breaker pulling, switch flipping and real time mis-interpretation of symptoms that drive the story-teller's probability of success (both UP and DOWN) during his/her narrow escape. As a professional, you had a different set of teachers than did us lowly tin-can drivers. Unless a pilot takes a special interest in understanding things like failure mode effects analysis and deducing actions that are useful or at least don't make things worse, then the outcome is problematic. To make matters worse, those who publish such stories seem never offer a de-briefing and lessons-learned study by teachers who DO understand the system. (See chapter 17 of the 'Connection) The 'education' may be worse than having not printing the story in the first place. It is difficult to perform to standards any greater than our level of education makes possible. Bob . . . ________________________________________________________________________________
Subject: Re: Questions about circuit protection
From: "user9253" <fran4sew(at)banyanol.com>
Date: Jan 04, 2010
Schu, Thanks for the info about using Visio. As for an oil pressure switch, your engine needs an oil pressure port and the switch threads would have to match. I do not know where to buy it. There was a recent discussion on AeroElectric about Hobbs meters. Read what others said: http://forums.matronics.com/viewtopic.php?t=66204&highlight=hobbs Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=280101#280101 ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Z-14 Switch Combos
At 09:08 PM 1/2/2010, you wrote: >I'm getting a handle on Z-14 from an operational perspective and >have a couple of questions about the switch combinations that could >create issues. > >Obviously with the added complexity of managing two batteries, two >alternators, and a cross feed can create some interesting combinations. > >Are there any combo's that we should be aware of that would create >over voltage or any other scenarios of concern? > >In the event of a failure (for example Alt 2 failure), is there a >specific order for shutting off the bad alt and then enabling the cross feed? No . . . there's no risks for any 'mis management' of switches. But you may not close the cross-feed ever. Depending on what YOU power from each of the two busses, how YOU use the airplane and which alternator quit, you need to re-configure the system to maximize probablity of a no sweat arrival at airport of intended destination. This MIGHT call for immediate closure of the cross-feed (but probably not). Or it might remain open with one bus shut down completely until airport is in sight. Z-14 is just a fancier version of Z-13/8 which is a fancier version of Z-11 with an E-bus. The level of fanciness only drives your decisions on best utilization of limited resources for engine driven power. That procedure is something that you have to develop. Bob . . . ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Simplicity and circuit protection
At 02:42 PM 1/2/2010, you wrote: >The FAA has just released SAIB CE-10-11 "Electrical: Fire Hazard in >Resetting Circuit Breakers" for operators of TC aircraft and >transports, but the implications of it gives Bob's advice that much >more teeth, IMHO. To summarize, the Feds are recommending that >circuit breakers NOT be reset once they trip except under specific >circumstances. The complete SAIB can be found here: > >https://www.faasafety.gov/files/notices/2009/Dec/SAIB_CE-10-11.pdf > > > So, if you shouldn't reset them, what good are they? Exactly what they were designed for . . . keep a single system fault from propagating to other systems or more serious symptoms. In hindsight, we would have been better off since day-one had TC aircraft designers had be chartered to design for failure tolerance (el- cheeso parts not necessarily poor value) as opposed to failure avoidance (gross reliability). After all, the earliest electrical systems were pure automotive bolt-on hardware. Not necessarily evil but they could have evolved in more practical directions if we had no placed them on pedestals and started certifying their socks off. If I were chartered to craft a system with breakers I'm pretty certain I'd figure out a way to make the breaker panel just as inaccessible as the fuse blocks. This forces the design off in new and more useful directions. Bob . . . ________________________________________________________________________________
Subject: Re: Questions about circuit protection
From: "user9253" <fran4sew(at)banyanol.com>
Date: Jan 04, 2010
> I looked at the dynamo relay coil but it is wired exactly as shown in > Z-25 and Z-13/8. Schu, It looks like I was wrong about the diode missing from your dynamo relay coil. The over-voltage protection probably shorts out any spike and thus the diode is not needed. As for the two diodes, they isolate the two power sources from each other. The dynamo is one source and the other source is a combination of the battery and main alternator. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=280106#280106 ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: THE VIRTUE OF SIMPLICITY
At 12:10 PM 1/2/2010, you wrote: To play the part of the loyal opposition: Yes, but. Do any of us really want to depend on one of the old cars for daily transportation? I have memories, almost all bad, of the old clunkers. I love my modern autos, turn the switch and they start and run. Oil changes at greatly increased intervals, hardly any "tune-ups" and such. How does "simplicity" translate into "old" hardware or degraded service life? These are, after all, experimental. Experiment as you wish. Let's just be aware of all the costs of adding equipment. BTW, I'm flying an Aircoupe now. When my RV-9A is finished I don't think I'll notice a few extra pounds in comparison...and besides, most of us Americans could easily make up for added equipment weight by losing our spare tires I think you missed the significance. The kind of simplicity we strive for is the minimum cost, parts count, weight and therefore maximum reliability of any one system. If your design goals call for lots of bells and whistles in your airplane, the minimalist rule for selection of systems suggests that those accessories with fewest components while meeting design goals are a better value. I'm having a good time designing accessories with micro-controllers where software replaces a bucket-load of components while allowing me to do more with fewer parts. Capability goes up while parts count goes down. I think this tread got started with a List member's notions of adding more busses and switches to Z-13/8 followed by questions of design goals to be met while doing so. Bob . . . ________________________________________________________________________________
From: "Tim Andres" <tim2542(at)sbcglobal.net>
Subject: Re: Questions about circuit protection
Date: Jan 04, 2010
Matt wont your EFIS track your hours for you? Maybe you don't need a Hobbs at all. I know the GRT stuff does this, I believe it tracks engine and flight time separately and automatically. I bet your AFS does as well. Tim -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Matthew Schumacher Sent: Monday, January 04, 2010 11:27 AM Subject: Re: AeroElectric-List: Re: Questions about circuit protection user9253 wrote: > > Schu, > > No switch is shown for the Hobbs meter. I assume that an oil pressure switch will be connected in series with it. > > The diode across the E-Bus relay is backwards. > > The spike protection diode is missing from the dynamo relay coil. The arrow should point towards positive. > > No over-voltage protection is shown for the main alternator. Over-voltage protection will do more towards safeguarding avionics than an avionics master switch. > > Since there are only two devices connected to the avionics bus, an avionics bus is not needed. Just connect those two devices to the switch without having a bus. Better yet, use two switches. If one of the devices starts smoking, you can shut it off and continue to use the other. Wire the E-Bus diode directly to the main power bus without a switch. An avionics master switch makes it convenient to shut off all of the avionics at once. But when it fails, so will everything connected to it. In addition, individual downstream switches will not get exercised, leading to corrosion and eventual failure of seldom used switches. > > Fuses offer better protection than circuit breakers. And fuses are less expensive. Yes, more than one load can be connected to a fuse or circuit breaker. But if one of the loads shorts out, it will blow the fuse and remove power from the other loads. It is better to install a larger fuse block so that each load can have its own fuse. Regulations for type certificated aircraft require that critical fuses be replaceable in flight. However, it is better not to have any critical equipment. Backup equipment makes critical devices non-critical. Fuses should be replaced on the ground, not in the air. > > I like your schematic. What program do you use to draw it and to convert it a pdf? > > Joe > > Joe, Thanks for your helpful comments. I would like to get an oil pressure switch for the hobbs (and for an idiot light) but I don't know where to source that. I looked around at Aircraft Spruce but didn't find anything. Do you know where I can find this? Thanks for finding the diode issues. I'll correct them in the drawing. There is over voltage protection internal to the main alternator since it is a plane power unit. The schematic was written in visio with the aeroelectric stencil set: http://www.lucubration.com/open-source-projects/aeroelectric-visio-symbols.h tml Converting to pdf is a little bit more involved but not bad (right Tim?). Simply install any postscript compatible printer (I like the apple color laser PS models), then tell windows that the port used is "save as file." When you print to that printer then it will prompt you for a file name, call the file drawing.ps or whatever, then use a postscript to pdf converter to make the pdf. A free online one is http://ps2pdf.com . The advantage to doing it this way is postscript is a vector based image not raster. This means that it isn't a 'picture' as much as a set of points what the printer fills in (not unlike a cad file.) This is why the file size is so small and why you can zoom in as close as you want and the edges are still sharp. The pdf viewer can re-render the image at any ratio. Clear as mud? schu ________________________________________________________________________________
From: "Carlos Trigo" <trigo(at)mail.telepac.pt>
Subject: Question about 16V POLYFUSER Radial Leaded Resettable
PTC Available at Digi-Key
Date: Jan 04, 2010
Polyfuses only reset themselves IF the cause that made them to trip disappears. Carlos _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Ron Quillin Sent: segunda-feira, 4 de Janeiro de 2010 4:28 Subject: Re: AeroElectric-List: Question about 16V POLYFUSER Radial Leaded Resettable PTC Available at Digi-Key At 19:41 1/3/2010, you wrote: Looks like one could use these instead of fuses or the traditional circuit breakers (for the average range of protection) But my question is do these trip the same as typical fuses ? I know they can reset but would it work like a fuse for time to trip or protection of the wire ? Are we sure we want a device that can reset itself? Doesn't that pretty much violate the premise of not resetting a tripped breaker? http://www.littelfuse.com/design/literature/fuse-vs-ptc/resettable-ptcs.html ________________________________________________________________________________
Date: Jan 04, 2010
From: Matthew Schumacher <schu(at)schu.net>
Subject: Re: Questions about circuit protection
Tim Andres wrote: > > Matt wont your EFIS track your hours for you? Maybe you don't need a Hobbs > at all. I know the GRT stuff does this, I believe it tracks engine and > flight time separately and automatically. I bet your AFS does as well. > Tim It does, but I want something more reliable than the EFIS, and it also serves as total time which is nice, but your right, I can go without it. schu ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Questions about circuit protection.
> >Are the experimental avionics from Advanced Flight Systems, TruTrak >Flight Systems, Dynon Avionics, and Grand Rapids certified to DO-160? Don't know if they're "certified" . . . i.e. have conducted formal testing for which a report is produced. In any case, they should certainly be DESIGNED to DO-160 limits and capabilities. First, because its a good thing to do and secondly, because it's an easy thing to do. >I'm running the AFS box and don't see anything in the manual about >starting, but I do see this: > >"All aircraft must have protection diodes installed on their Master >Relay, Starter Relay and any other large relay. If your aircraft does >not have the protection diode on the Master Relay your electrical buss >will experience a voltage spike of 500+ Volts every time you turn off >the master switch. If your EFIS or Engine Monitor is wired directly to >the electrical buss it will be the device that absorbs the voltage spike >and will eventually fail. All users must verify that they have the >protection diodes installed before powering the EFIS or Engine Monitor." This is hogwash. When a relay's coil is un-suppressed, the energy stored on the coil's magnetic core is dissipated in the highest impedance portion of the loop. The bus structure's impedance is a tiny fraction of that which appears across the spreading contacts of the controlling switch or relay. Further, consider that while the spike from a coil collapse can be large, as an energy source its ability to transfer energy is limited to the same current that energizes the relay. For example, suppose you DID have a 500v battery that was absolutely limited to 1 amp of output current. Now, connect that battery across the bus that's got several amps of load already present along with a battery and several capacitors inside sundry appliances. Folks like to cite that 500v spike without telling you that its current delivery is limited to 1A. I.e. it's trivial to all devices except the controlling switch. This is stone simple to demonstrate in the lab, on an airplane or in any dc powered vehicle. Who ever wrote those words was simply repeating something they'd been misled into writing. Bob . . . ________________________________________________________________________________
From: "Carlos Trigo" <trigo(at)mail.telepac.pt>
Subject: Re: Questions about circuit protection
Date: Jan 05, 2010
Whenever this "fuses versus circuit breakers" discussion comes afloat, I always wonder why TC aircraft always used circuit breakers. Carlos > -----Original Message----- > From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list- > server(at)matronics.com] On Behalf Of user9253 > Sent: segunda-feira, 4 de Janeiro de 2010 16:47 > To: aeroelectric-list(at)matronics.com > Subject: AeroElectric-List: Re: Questions about circuit protection > ....... snip ..... > > > Fuses offer better protection than circuit breakers. And fuses are less expensive. > Yes, more than one load can be connected to a fuse or circuit breaker. But if one > of the loads shorts out, it will blow the fuse and remove power from the other loads. > It is better to install a larger fuse block so that each load can have its own fuse. > Regulations for type certificated aircraft require that critical fuses be replaceable in > flight. However, it is better not to have any critical equipment. Backup equipment > makes critical devices non-critical. Fuses should be replaced on the ground, not in > the air. > > > Joe > ________________________________________________________________________________
From: "Ralph & Maria Finch" <ralphmariafinch(at)gmail.com>
Subject: THE VIRTUE OF SIMPLICITY
Date: Jan 04, 2010
I think you missed the significance. The kind of simplicity we strive for is the minimum cost, parts count, weight and therefore maximum reliability of any one system. I think you missed my point. For example, the OP equated simplicity with less weight, which might be literally true but is irrelevant, because the weight saved is probably trivial. That's a notion from value engineering...those evil and arrogant engineers again. Minimum cost? Minimum parts count? Really? The least cost, greatest simplicity, maximum safety, minimum parts count, and least weight, is...no plane at all. Seriously. Absurd? Probably, but it makes the point that it's foolish to use "minimum", "maximum", and similar extreme or unbalanced terms in a discussion like this. If your design goals call for lots of bells and whistles in your airplane No. Don't be silly. My design goals include better reliability, ease of use, and maintenance than certificated aircraft, balanced with cost considerations. To achieve those goals I will use modern systems where I think appropriate. It doesn't include gizmotrons for the sake of gadgetry, or saving a few pounds because the "airplane will perform better". Other friends of mine have different goals, or perhaps the same goals but different decisions to arrive at the same goals. I'm having a good time designing accessories with micro-controllers where software replaces a bucket-load of components while allowing me to do more with fewer parts. Capability goes up while parts count goes down. I'm sincerely glad to hear this. I would be quite interested if you provided lessons in two related areas: 1. How to design the few conventional electrical parts a microcontroller needs, that is, the resistors, inductors, caps and perhaps transistor or two needed. 2. Basic programming of a microcontroller. I'm comfortable with programming several high-level languages, and years ago knew some assembly, but a class or lessons would be great. I'd be very willing to pay for a well-designed set of lessons for this knowledge. At this time--a couple of years before I actually must decide--I intend to use Vertical Power's electrical system to wire my aircraft. Many electromechanical devices are replaced with a few solid-state devices and software...approaching what cars have had for decades. I consider it a significant step towards greater simplicity, fewer parts, less weight, and greater reliability. Of course many differ. I know builders who consider round gages the way to go for greater reliability; to each their own in the OBAM world. I think this tread got started with a List member's notions of adding more busses and switches to Z-13/8 followed by questions of design goals to be met while doing so. I'll take your word for it. The OP's post didn't say anything about that. BTW Bob, have you thought about memristors, and how they might change electrical/electronic design (not just for aircraft systems, but in general). They are the fourth, long forgotten basic electrical component, just now coming into practical use. I wonder how much of a change in design and future device capability they might start. __________ Information from ESET Smart Security, version of virus signature database 4742 (20100104) __________ The message was checked by ESET Smart Security. ________________________________________________________________________________
Subject: Re: Question about 16V POLYFUSER Radial Leaded Resettable
PTC
From: "marcausman" <marc(at)verticalpower.com>
Date: Jan 04, 2010
See AC 43.13, chapter 11 quoted below: 11-50. RESETTABLE CIRCUIT PROTECTION DEVICES. a. All resettable type circuit breakers must open the circuit irrespective of the position of the operating control when an overload or circuit fault exists. Such circuit breakers are referred to as trip free. b. Automatic reset circuit breakers, that automatically reset themselves periodically, are not recommended as circuit protection devices for aircraft. -------- Marc Ausman http://www.verticalpower.com "Move up to a modern electrical system" RV-7 IO-390 Flying Read this topic online here: http://forums.matronics.com/viewtopic.php?p=280156#280156 ________________________________________________________________________________
Subject: Z-14 Switch Combos
Date: Jan 04, 2010
From: "Perry, Phil" <Phil.Perry(at)netapp.com>
So we were on a good path until, "But you may not close the cross-feed ever." If that's the case, what good is the cross-feed if the switch is off limits??? I think your intentions were to say only in an emergency when it is required? Let's looks a scenario where I forget to open the cross-feed after start. The other two contactors for the Alt/Batt are closed too. What are the effects of the electrical system for prolonged cross-feed closure on a cross country tour across the southern states? Any battery damage? My guess is that the alternators would be shedding load back and forth for the flight and never stabilize. I think I'm getting closer to understanding it. I just want to make sure I understand everything operationally before I dedicate myself to a specific diagram only to be disappointed later. Thanks again for your help, Phil -----Original Message----- From: Robert L. Nuckolls, III [mailto:nuckolls.bob(at)aeroelectric.com] Sent: Monday, January 04, 2010 2:07 PM Subject: Re: AeroElectric-List: Z-14 Switch Combos At 09:08 PM 1/2/2010, you wrote: >I'm getting a handle on Z-14 from an operational perspective and >have a couple of questions about the switch combinations that could >create issues. > >Obviously with the added complexity of managing two batteries, two >alternators, and a cross feed can create some interesting combinations. > >Are there any combo's that we should be aware of that would create >over voltage or any other scenarios of concern? > >In the event of a failure (for example Alt 2 failure), is there a >specific order for shutting off the bad alt and then enabling the cross feed? No . . . there's no risks for any 'mis management' of switches. But you may not close the cross-feed ever. Depending on what YOU power from each of the two busses, how YOU use the airplane and which alternator quit, you need to re-configure the system to maximize probablity of a no sweat arrival at airport of intended destination. This MIGHT call for immediate closure of the cross-feed (but probably not). Or it might remain open with one bus shut down completely until airport is in sight. Z-14 is just a fancier version of Z-13/8 which is a fancier version of Z-11 with an E-bus. The level of fanciness only drives your decisions on best utilization of limited resources for engine driven power. That procedure is something that you have to develop. Bob . . . ________________________________________________________________________________
From: "Bill Hibbing" <n744bh(at)bellsouth.net>
Subject: A reminder
Date: Jan 04, 2010
This is off the aero electric topic but I thought that I would pass along a reminder that the paper pilot certificates become invalid I believe sometime in March. Also, if you do have the new plastic certificate make sure that you have the "English proficient" endorsement on the back and if not it's just $2.00 to get a new one. Service has been pretty quick from the FAA. Bill Glasair SIIS-FT ________________________________________________________________________________
Date: Jan 04, 2010
Subject: Re: GTX337 ON or OFF?
From: thomas sargent <sarg314(at)gmail.com>
The GTX-327 in my plane has the same undesirable behavior. I called Garmin who said it was due to harness wiring and I should call Stark Avionics, who I bought the thing from. John Stark says they wire the connector assuming there is going to be an avionics master switch, which he strongly recommends. I am convinced by Bob K. that the avionics master is not necessary. John tells me that the fix (which I haven't tried yet) is to cut the wire to pin 1 on the connector and cover up the loose wire with heat shrink or something so it won't short to anything. I wish I'd known this when the thing was easier to get at. It's fully installed now. Sigh. On Fri, Jan 1, 2010 at 12:22 PM, wrote: > > 1/1/2010 > > Hello Allen Fullmer, You wrote: > > "........skip.....I have also noticed that the GTX337 transponder cannot be > set to remain off when power is supplied. It will remain in the standby > position but, once again, when I am playing and fiddling around I just hate > to see it go up and down unnecessarily. Haven't decided on a switch for it > or not." > > I also can not program my GTX327 to remain OFF when power is applied or > reapplied to the avionics buss.** But the GTX327 has some options on which > pins electrical power can be supplied to. If you pick the correct pin(s) the > box will remain OFF until you push the ON button on the face of the box. > > I suspect that the GTX337 may be built the same way. So if you desire, and > have the capability, you could rewire your GTX337 so that it would remain > OFF until you pushed the ON button on the face of the box. > > 'OC' Says: "The best investment we can make is the effort to gather and > understand knowledge." > > **PS: I suspect that the person who wired my panel set it up that way so > that it would take a very deliberate OFF button action on my part in order > to take off with the transponder OFF. I am with you, I'd like to have total > ON - OFF control of the box with the buttons on the face of the box. > > -- Tom Sargent ________________________________________________________________________________
From: "William Slaughter" <william_slaughter(at)att.net>
Subject: Z-14 Switch Combos
Date: Jan 04, 2010
I believe that "may not..." should be translated as "may never have occasion to", rather than "you must not do that". At least that's the way I read it. William -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Perry, Phil Sent: Monday, January 04, 2010 2:35 PM Subject: RE: AeroElectric-List: Z-14 Switch Combos So we were on a good path until, "But you may not close the cross-feed ever." If that's the case, what good is the cross-feed if the switch is off limits??? I think your intentions were to say only in an emergency when it is required? Let's looks a scenario where I forget to open the cross-feed after start. The other two contactors for the Alt/Batt are closed too. What are the effects of the electrical system for prolonged cross-feed closure on a cross country tour across the southern states? Any battery damage? My guess is that the alternators would be shedding load back and forth for the flight and never stabilize. I think I'm getting closer to understanding it. I just want to make sure I understand everything operationally before I dedicate myself to a specific diagram only to be disappointed later. Thanks again for your help, Phil -----Original Message----- From: Robert L. Nuckolls, III [mailto:nuckolls.bob(at)aeroelectric.com] Sent: Monday, January 04, 2010 2:07 PM Subject: Re: AeroElectric-List: Z-14 Switch Combos At 09:08 PM 1/2/2010, you wrote: >I'm getting a handle on Z-14 from an operational perspective and >have a couple of questions about the switch combinations that could >create issues. > >Obviously with the added complexity of managing two batteries, two >alternators, and a cross feed can create some interesting combinations. > >Are there any combo's that we should be aware of that would create >over voltage or any other scenarios of concern? > >In the event of a failure (for example Alt 2 failure), is there a >specific order for shutting off the bad alt and then enabling the cross feed? No . . . there's no risks for any 'mis management' of switches. But you may not close the cross-feed ever. Depending on what YOU power from each of the two busses, how YOU use the airplane and which alternator quit, you need to re-configure the system to maximize probablity of a no sweat arrival at airport of intended destination. This MIGHT call for immediate closure of the cross-feed (but probably not). Or it might remain open with one bus shut down completely until airport is in sight. Z-14 is just a fancier version of Z-13/8 which is a fancier version of Z-11 with an E-bus. The level of fanciness only drives your decisions on best utilization of limited resources for engine driven power. That procedure is something that you have to develop. Bob . . . ________________________________________________________________________________
From: "Neal George" <n8zg(at)mchsi.com>
Subject: Z-14 Switch Combos
Date: Jan 04, 2010
Phil - I think you misinterpreted Bob's comment. It appears you read it to say "you're never ALLOWED to close the cross-feed switch", when Bob meant "you might not ever have a reason to close it". Neal So we were on a good path until, "But you may not close the cross-feed ever." If that's the case, what good is the cross-feed if the switch is off limits??? I think your intentions were to say only in an emergency when it is required? Phil ________________________________________________________________________________
From: "Bob McCallum" <robert.mccallum2(at)sympatico.ca>
Subject: Z-14 Switch Combos
Date: Jan 04, 2010
Phil and William; My reading of the statement agrees with William's translation as well. Bob McC > -----Original Message----- > From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list- > server(at)matronics.com] On Behalf Of William Slaughter > Sent: Monday, January 04, 2010 10:39 PM > To: aeroelectric-list(at)matronics.com > Subject: RE: AeroElectric-List: Z-14 Switch Combos > > > > I believe that "may not..." should be translated as "may never have occasion > to", rather than "you must not do that". At least that's the way I read it. > > William > > -----Original Message----- > From: owner-aeroelectric-list-server(at)matronics.com > [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Perry, > Phil > Sent: Monday, January 04, 2010 2:35 PM > To: aeroelectric-list(at)matronics.com > Subject: RE: AeroElectric-List: Z-14 Switch Combos > > > > So we were on a good path until, "But you may not close the cross-feed > ever." > > If that's the case, what good is the cross-feed if the switch is off > limits??? I think your intentions were to say only in an emergency when > it is required? > > Let's looks a scenario where I forget to open the cross-feed after > start. The other two contactors for the Alt/Batt are closed too. What > are the effects of the electrical system for prolonged cross-feed > closure on a cross country tour across the southern states? Any battery > damage? > > My guess is that the alternators would be shedding load back and forth > for the flight and never stabilize. > > I think I'm getting closer to understanding it. I just want to make > sure I understand everything operationally before I dedicate myself to a > specific diagram only to be disappointed later. > > Thanks again for your help, > Phil > > > > > > > > -----Original Message----- > From: Robert L. Nuckolls, III [mailto:nuckolls.bob(at)aeroelectric.com] > Sent: Monday, January 04, 2010 2:07 PM > To: aeroelectric-list(at)matronics.com > Subject: Re: AeroElectric-List: Z-14 Switch Combos > > > > At 09:08 PM 1/2/2010, you wrote: > >I'm getting a handle on Z-14 from an operational perspective and > >have a couple of questions about the switch combinations that could > >create issues. > > > >Obviously with the added complexity of managing two batteries, two > >alternators, and a cross feed can create some interesting combinations. > > > >Are there any combo's that we should be aware of that would create > >over voltage or any other scenarios of concern? > > > >In the event of a failure (for example Alt 2 failure), is there a > >specific order for shutting off the bad alt and then enabling the > cross feed? > > No . . . there's no risks for any 'mis management' of > switches. But you may not close the cross-feed ever. > > Depending on what YOU power from each of the two busses, > how YOU use the airplane and which alternator quit, you > need to re-configure the system to maximize probablity > of a no sweat arrival at airport of intended destination. > This MIGHT call for immediate closure of the cross-feed > (but probably not). Or it might remain open with one > bus shut down completely until airport is in sight. > > Z-14 is just a fancier version of Z-13/8 which is a > fancier version of Z-11 with an E-bus. The level > of fanciness only drives your decisions on best > utilization of limited resources for engine driven > power. That procedure is something that you have > to develop. > > Bob . . . > > > > > > > > > > > > > _- > =================================================== > ======= > _- > =================================================== > ======= > _- > =================================================== > ======= > _- > =================================================== > ======= > > ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Battery Bus Location
At 08:17 AM 1/3/2010, you wrote: > >I'm working on locating items on the firewall and have a question on >location of the alway hot battery bus. I know that there is a >length limit on the wire powering this bus and with that in mind, it >seems the ideal location for the fuse block is on the hot side of >the firewall. > >Is this block and fuse combination okay to put on the hot >side? Seems like it defeats the purpose of this bus if it's feeder >line is fused and then put on the cool side of the firewall. Where do you want to put it? Lots of fuse/relay boxes go under the hood on cars. However, they're generally covered. The Bussmann fuse-blocks are open. If you want to put it inside, you can run the bus feeder through the fire wall with some judicious attention to support and insulation. Here's an example of a small ceramic (thus fireproof) feed through insulator: Emacs! This one is available from http://www.surplussales.com/antennas/antennas-6.html for about $5. Use fire-seal putty as an installation sealant. Bob . . . ________________________________________________________________________________
Date: Jan 04, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Questions about circuit protection
At 01:56 PM 1/4/2010, you wrote: > >user9253 wrote: > > The spike protection diode is missing from the dynamo relay > coil. The arrow should point towards positive. > >Joe, > >I looked at the dynamo relay coil but it is wired exactly as shown in >Z-25 and Z-13/8. > >Bob, I would be very grateful if you could explain what the two diodes >are for on the self exciting SD-8 drawing since since they are wired >differently than the other relays. Those are "steering" diodes that make power available from either the battery or a spinning alternator to get the relay to energize. The relay doesn't need an coil suppression diode with an OV module installed. Bob . . . ________________________________________________________________________________
Subject: Z-14 Switch Combos
Date: Jan 04, 2010
From: "Perry, Phil" <Phil.Perry(at)netapp.com>
Awesome.. I get it now.. Thanks for the help and clarification... Phil -----Original Message----- From: Bob McCallum [mailto:robert.mccallum2(at)sympatico.ca] Sent: Monday, January 04, 2010 10:11 PM Subject: RE: AeroElectric-List: Z-14 Switch Combos Phil and William; My reading of the statement agrees with William's translation as well. Bob McC > -----Original Message----- > From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list- > server(at)matronics.com] On Behalf Of William Slaughter > Sent: Monday, January 04, 2010 10:39 PM > To: aeroelectric-list(at)matronics.com > Subject: RE: AeroElectric-List: Z-14 Switch Combos > > > > I believe that "may not..." should be translated as "may never have occasion > to", rather than "you must not do that". At least that's the way I read it. > > William > > -----Original Message----- > From: owner-aeroelectric-list-server(at)matronics.com > [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Perry, > Phil > Sent: Monday, January 04, 2010 2:35 PM > To: aeroelectric-list(at)matronics.com > Subject: RE: AeroElectric-List: Z-14 Switch Combos > > > > So we were on a good path until, "But you may not close the cross-feed > ever." > > If that's the case, what good is the cross-feed if the switch is off > limits??? I think your intentions were to say only in an emergency when > it is required? > > Let's looks a scenario where I forget to open the cross-feed after > start. The other two contactors for the Alt/Batt are closed too. What > are the effects of the electrical system for prolonged cross-feed > closure on a cross country tour across the southern states? Any battery > damage? > > My guess is that the alternators would be shedding load back and forth > for the flight and never stabilize. > > I think I'm getting closer to understanding it. I just want to make > sure I understand everything operationally before I dedicate myself to a > specific diagram only to be disappointed later. > > Thanks again for your help, > Phil > > > > > > > > -----Original Message----- > From: Robert L. Nuckolls, III [mailto:nuckolls.bob(at)aeroelectric.com] > Sent: Monday, January 04, 2010 2:07 PM > To: aeroelectric-list(at)matronics.com > Subject: Re: AeroElectric-List: Z-14 Switch Combos > > > > At 09:08 PM 1/2/2010, you wrote: > >I'm getting a handle on Z-14 from an operational perspective and > >have a couple of questions about the switch combinations that could > >create issues. > > > >Obviously with the added complexity of managing two batteries, two > >alternators, and a cross feed can create some interesting combinations. > > > >Are there any combo's that we should be aware of that would create > >over voltage or any other scenarios of concern? > > > >In the event of a failure (for example Alt 2 failure), is there a > >specific order for shutting off the bad alt and then enabling the > cross feed? > > No . . . there's no risks for any 'mis management' of > switches. But you may not close the cross-feed ever. > > Depending on what YOU power from each of the two busses, > how YOU use the airplane and which alternator quit, you > need to re-configure the system to maximize probablity > of a no sweat arrival at airport of intended destination. > This MIGHT call for immediate closure of the cross-feed > (but probably not). Or it might remain open with one > bus shut down completely until airport is in sight. > > Z-14 is just a fancier version of Z-13/8 which is a > fancier version of Z-11 with an E-bus. The level > of fanciness only drives your decisions on best > utilization of limited resources for engine driven > power. That procedure is something that you have > to develop. > > Bob . . . > > > > > > > > > > > > > _- > =================================================== > ======= > _- > =================================================== > ======= > _- > =================================================== > ======= > _- > =================================================== > ======= > > ________________________________________________________________________________
From: <bakerocb(at)cox.net>
Subject: Questions about circuit protection
Date: Jan 05, 2010
1/3/2010 -- 1/5/2010 Hello Bob Nuckolls, May I "Make your day by showing you where you are wrong?" You wrote (see your posting copied below): "First, 14 CFR 91.205 doesn't apply to an amateur built airplane." and "....... but you have no obligation to consult these documents that apply to type certificated aircraft only." Those statements are not correct. Each experimental amateur built aircraft will be issued an initial airworthiness certificate in accordance with FAA Order 8130.2F (or the current version of that order). That airworthiness certificate will include a number of Operating Limitations, written in accordance with that order, that apply to that specific aircraft. Per FAA Order 8130.2F the Operating Limitations will state: "After completion of Phase I flight testing, unless appropriately equipped for night and/or instrument flight in accordance with 91.205, this aircraft is to be operated under VFR, day only." That sentence means that if one is operating his aircraft at night or in instrument conditions it must be equipped in accordance with 91.205. The attached document will provide additional details on this subject. 'OC' Says: "The best investment we can make is the effort to gather and understand knowledge." ========================================================== From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> Subject: Re: AeroElectric-List: Questions about circuit protection >Hold on, back the truck up. Are you saying that if I put the fuses >under the panel where they aren't accessible then my airplane will still >meet 14 CFR 91.205 (c) and that I won't need to carry spares? > >I would read "that are accessible to the pilot in flight" to mean that >the fuse panel is accessible to the pilot, not the fusees since who >cares if you can get to the fuses if you can't get to the panel. First, 14 CFR 91.205 doesn't apply to an amateur built airplane. That's not to imply that the FARS don't have some things to be considered . . . but you have no obligation to consult these documents that apply to type certificated aircraft only. Further, 91.205 isn't the ONLY milestone at which your project is essentially "un-certifiable". But assume you adopt failure tolerance as a design goal. For every piece of equipment "critical" for the manner in which you plan to use the airplane, then that piece of equipment needs to be backed up with a plan-B. There are 100 times more failures in a piece of electronics that DOES NOT blow a fuse than there are failures that DO blow a fuse. If that piece of equipment is deemed critical, then having spare fuses for the circuit that supports that system is whistling in the dark. So assuming you have a back up for every POTENTIALLY critical system, then if follows that there are NO critical systems. Hence, whether or not you can reach breakers or fuses for any system is immaterial. Bob . . . ________________________________________________________________________________
Date: Jan 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Question about 16V POLYFUSER Radial Leaded
Resettable PTC Available at Digi-Key At 05:36 PM 1/4/2010, you wrote: >Polyfuses only reset themselves IF the cause that made them to trip >disappears. > >Carlos Sort of . . . the thing that trips a polyfuse is passage of the minimum current to warm it beyond the trip point while it is relatively cool. Once it trips, the reistance goes to a high state where it's EASIER to keep it warm because presumably, the power is still on, the protected circuit is still drawing the minimal "keep it tripped" current. I think some folks have pointed out that depending on the sophistication of the device on the protected circuit the current drawn through the polyfuse in a "tripped" state will be insufficient to keep it hot and in a safe . . . low current condition. In some cases, one could experience an kind of low frequency oscillation where the circuit trips, the polyswitch cools and resets and the process repeats. There are so many interactive variables to consider that I hope it's obvious that the polyfuse is NOT a blanket replacement for fuses or breakers. Even when all the protection dynamics are found acceptable, there's still the problem of how do you mount these things in a manner suited to the aircraft power distribution system environment. Finally, one should consider how they affect the legacy failure mode effects study that calls for understanding how the pilot becomes aware of a problem with the system such that the plan-a/plan-b decision can be made. I'm pretty confident that the designers of the polyswitch never envisioned this device to be a replacement in the classic applications for breakers or fuses. The polyswitch offered designers a NEW opportunity to add protection inside some device where the use of a breaker or fuse was impractical. In these situations, the designer of the appliance can analyze the failure modes independently of the all-up system (i.e. an airplane full of electro- whizzies). The idea that we can simply craft some sort of power distribution etched circuit board to make a blanket replacement of legacy power distribution systems is a whole new ball game. As I've written many times . . . the polyswitch WILL always keep a wire from catching fire. Circuit protection safety is not the issue. Polyswitches throw a wrench into the gears for how we think about operating the system when the unexpected and unwelcome event occurs. Bob . . . ________________________________________________________________________________
Date: Jan 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Questions about circuit protection
At 06:52 PM 1/4/2010, you wrote: >Whenever this =93fuses versus circuit breakers=94 >discussion comes afloat, I always wonder why TC >aircraft always used circuit breakers=85 > >Carlos They didn't. The first airplanes to get electrical systems at Cessna used fuses. They were cartridge fuse holders with caps that could easily be dropped on the floor and be difficult to find. When miniature, low cost breakers came along, they offered a means by which operational and environmental concerns for the use of glass cartridge fuses could be addressed. It wasn't until the blade fuse came along that environmental issues were resolved for re-considering fuses in airplanes. It wasn't until we address the ideas of failure tolerant system design that the operational issues were resolved. If the TC aircraft guys were so disposed, they could do exactly what we're doing right now. But regulatory inertia makes this unlikely to happen. Bob . . . ________________________________________________________________________________
Date: Jan 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Question about 16V POLYFUSER Radial Leaded Resettable
PTC Available at Digi-Key At 11:16 AM 1/4/2010, you wrote: Hi Jeff I designed and have been using an electrical system similar to the EXP bus for over a year, for no reason other than experimentation. I chose a variety of these, ranging from 1A up to 16A... They work as advertised, and have found their trip performance similar to that of CB's, i.e. a 2A polyswitch probably won't trip at 2A, unless the device draws 2A for minutes almost. 2.5A will trip after a few seconds, 5A will trip after a second, and 100A will trip almost instantaneously. So to answer your questions, yes I think they can replace CB's or standard fuses, but I don't think they should. The fact that they reset themselves whenever power is cycled means that a tripped system will not stay tripped if you turn off the master switch. Standard fuses are much better-suited to the task. And that's in my humble opinion Great observation. Bob . . . ________________________________________________________________________________
Date: Jan 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Question about 16V POLYFUSER Radial Leaded
Resettable PTC At 08:28 PM 1/4/2010, you wrote: > >See AC 43.13, chapter 11 quoted below: > >11-50. RESETTABLE CIRCUIT PROTECTION >DEVICES. >a. All resettable type circuit breakers >must open the circuit irrespective of the position >of the operating control when an overload >or circuit fault exists. Such circuit breakers are >referred to as trip free. >b. Automatic reset circuit breakers, that >automatically reset themselves periodically, are >not recommended as circuit protection devices >for aircraft. This paragraph has been in there for decades . . . LONG before things like the polyfuse came along. The self-resetting breakers of yesteryear were simple adaptations of manual resetting breakers. Many cars used self-resetting breakers on headlight circuits in lieu of fuses. These devices would ALWAYS reset when they cooled. Unlike the polyfuse which will probably stay tripped until power is removed, the self-resetting breaker of 1950 would definitely oscillate between a zero- current to fault-current condition as long as power was still on. Bob . . . ________________________________________________________________________________
Date: Jan 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Z-14 Switch Combos
At 09:08 PM 1/4/2010, you wrote: > >Phil - > >I think you misinterpreted Bob's comment. It appears you read it to say >"you're never ALLOWED to close the cross-feed switch", when Bob meant "you >might not ever have a reason to close it". > >Neal Correct. The process for deciding how to operate Z-14 is dependent upon what devices are fed from each bus and how you use the airplane. Z-14 was originally crafted for a guy building a Glasair with full up IFR capability in both seats. Further, it was the builder's intent to use this machine in missions that most of us work hard to avoid. Z-14 offers OPTIONS for deciding how you will manage energy resources that have become limited due to failure of some component like an alternator or battery contactor. There is no SET PROCEDURE I can offer you without doing the same failure modes effects analysis I would conduct for a TC aircraft with a similar system installed and tailored to the most demanding mission for which the airplane is outfitted. Z-14's cross-feed contactor solved a problem with attempting to PARALLEL two alternators in a dual alternator airplane by making them responsible for SEPARATE systems in normal operations. Z-13/8 was crafted to take exploit the existence of an unused engine accessory drive pad when a vacuum pump is removed. Some politicians hate to waste a good crisis, I had to waste a good drive pad. When considered against the quantum jumps in reliability offered by modern alternators and artfully maintained RG batteries, I believe Z-13/8 is about the most elegant solution to powering up the light airplane for 99 plus percent of all OBAM aircraft. If you have Z-14 installed, then share with us how equipment in your airplane is powered from the two busses along with your vision of how you expect to use this airplane. Is it important to you to forestall a dark-n-stormy night story 'cause you've had an alternator go belly up while night IFR over the Rockies crossing a weather front? If so, what items of equipment are installed and how are they spread between the two systems? Bob . . . ________________________________________________________________________________
Date: Jan 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Questions about circuit protection
At 07:15 AM 1/5/2010, you wrote: >1/3/2010 -- 1/5/2010 > >Hello Bob Nuckolls, May I "Make your day by showing you where you are >wrong?" > >You wrote (see your posting copied below): > >"First, 14 CFR 91.205 doesn't apply to an amateur built airplane." Thanks for posting the review of instrumentation requirements! With your permission, I'll post it to aeroelectric.com and index it in the reference documents section. Bob . . . ________________________________________________________________________________
Subject: Re: Battery Bus Location
From: "PaulR" <prose(at)panhandle.rr.com>
Date: Jan 05, 2010
Bob, Thanks for the reply. I'm not opposed to putting it outside on the firewall, I just didn't know whether the fuse blocks from B&C would be alright out there. I think you spell out 6" length on the feed wire. If I stick to that, which makes sense unprotected, then I would have to put it directly on the inside of the firewall which would be extremely difficult to get to for service. Hopefully none will be required, but it would be easier on the hot side. The insulator would indeed be a good method to get the wire inside, but the length is still a factor. Does most everyone else put them on the hot side? Thanks -------- Paul Rose N417PR (res) RV-9A Read this topic online here: http://forums.matronics.com/viewtopic.php?p=280287#280287 ________________________________________________________________________________
Date: Jan 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Battery Equalizers
At 05:26 PM 12/29/2009, you wrote: Bob et al, I appreciate the architecture advice and will take it into consideration. Unfortunately, I'm on a work-driven building hiatus that'll probably keep me from doing any work on the Velocity for at least a couple years, so I won't be able to give any solid feedback on the usefulness of a battery equalizer in this setup for a while. In the meantime, I can do a quick trade study to look at the cost and parts count between the multiple bus setup and replacing the hydraulic power pack and associated control circuits. I don't know if you looked at the link to the white paper in my previous post or not, but in it the author shows significant experimental improvement in battery life using an equalizer in a series string of batteries. As I need a 24V system in my aircraft anyway and will be using two batteries in series, it makes sense to me to take advantage of these improvements if in fact the claims are true. Have you (or anyone on the list) looked at the white paper and/or have any knowledge or experience in the use and efficacy of these equalizers (regardless of whether I keep my multi-bus setup or not)? Dan, The IDEAL equalizer will, no doubt, make the 12v tap on a 24v battery look transparent to the rest of the system . . . including batteries. By "ideal" we mean equalizers that are about as capable as the batteries themselves . . . very low impedance and capable of carrying what ever loads are imposed at the tap. As soon as you choose an equalizer smaller than anticipated loads, then the lower battery MUST make up the difference. Yes, it's just for a short time and the too-small equalizer will fix things back up once the loads go away. Nonetheless, this means that the bottom half of the battery is treated differently than the top half. Terrible thing to do? Don't know. I have no experience with it in the distinctly aviation environment where batteries are protected against deep cycle and monitored for minimum capacity. How does one integrate a less than idea equalizer into the battery maintenance protocols? My gut feeling is that you'll be happier in the long run with a conversion of your 14v hardware to 28v hardware and forget the equalizer. But should you choose to conduct this experiment, you will become the go-to guy for guidance on how good an idea it is. Bob . . . ________________________________________________________________________________
Date: Jan 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Battery Bus Location
At 04:10 PM 1/5/2010, you wrote: > >Bob, >Thanks for the reply. I'm not opposed to putting it outside on the >firewall, I just didn't know whether the fuse blocks from B&C would >be alright out there. I think you spell out 6" length on the feed wire. That's an idealized notion. If you need to make it 12" or even longer to satisfy design goals, the world is not going to come to an end. > If I stick to that, which makes sense unprotected, then I would > have to put it directly on the inside of the firewall which would > be extremely difficult to get to for service. Hopefully none will > be required, but it would be easier on the hot side. Then put it in a location for ease of maintenance. That would be my choice as well. Think about a way to at least cover if not box-up the fuseblock like they do under the hood of cars. >The insulator would indeed be a good method to get the wire inside, >but the length is still a factor. The length isn't a REALLY BIG thing, just a good practice design rule adopted by the TC side of the house many years ago. How long would the wire be for both extending the battery feeder AND ease of maintenance? >Does most everyone else put them on the hot side? Good question. How about it guys? Anyone out there flying fuse blocks on the forward side of the firewall? Bob . . . ________________________________________________________________________________
Date: Jan 06, 2010
Subject: Tachometer problems
From: geoff winter <winter.geoff(at)gmail.com>
Hi All I fly a Corby Starlet using an 1835 VW with a Bendix D4 RN-2021 dual magneto. Both magnetos are grounded through separate magneto switches on my panel. I use one of these leads to also run my tachometer. This has all been working just fine, but I've now replaced the original Westach tacho with a new VDO tachourmeter, item # 333-035-11. I have the VDO tacho set for 4 stroke, 4 cylinder, single coil operation. The rpm reading appears accurate, but it is continually fluctuating. Every second or so the rpm drops anything from 200 to 1000 rpm momentarily, then returns to normal. Could anyone advise what I need to do to smooth out the reading. I've tried putting a diode inline with no joy. Could anyone suggest some specific combination of capacitor/resistor/diode inline or parallel to the tacho I could try to smooth things out? Failed to get any help from VDO so any advice would be very much appreciated. Cheers Geoff ________________________________________________________________________________
From: "Carlos Trigo" <trigo(at)mail.telepac.pt>
Subject: RE: [AeroElectric-List] Questions about circuit protection
Date: Jan 06, 2010
Bob I really don=92t want to resuscitate this discussion but, even being aware of the technical advantages of fuses versus circuit breakers, it is indeed almost impossible to convince a pilot that a fuse is better than a circuit breaker. In flight, when a fuse blows, the pilot will hardly notice it, and even if some device (whose circuit was protected by that fuse) becomes blank, he will not know if it was the fuse or anything else that caused that device to die. If a circuit breaker pops out, there is a big probability the pilot will immediately notice it, or at least after seeing any device die, he will immediately look to the circuit breakers heads to look for the one that popped out. Being a pilot trained for so many things, he must also know that he shall not push that particular breaker in, unless he wants to light up the fire which will burn his own ass=85 It is probably easy to convince an aircraft builder to prefer fuses, but since in the OBAM world we are builders AND pilots, circuit breakers are certainly much more user friendly for the pilot, even knowing that the PILOT is the most dangerous single-point-of-failure in a flying aircraft Carlos _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: ter=E7a-feira, 5 de Janeiro de 2010 15:03 Subject: RE: AeroElectric-List: Re: Questions about circuit protection At 06:52 PM 1/4/2010, you wrote: Whenever this =93fuses versus circuit breakers=94 discussion comes afloat, I always wonder why TC aircraft always used circuit breakers=85 Carlos They didn't. The first airplanes to get electrical systems at Cessna used fuses. They were cartridge fuse holders with caps that could easily be dropped on the floor and be difficult to find. When miniature, low cost breakers came along, they offered a means by which operational and environmental concerns for the use of glass cartridge fuses could be addressed. It wasn't until the blade fuse came along that environmental issues were resolved for re-considering fuses in airplanes. It wasn't until we address the ideas of failure tolerant system design that the operational issues were resolved. If the TC aircraft guys were so disposed, they could do exactly what we're doing right now. But regulatory inertia makes this unlikely to happen. Bob . . . ________________________________________________________________________________
Subject: Re: Question about 16V POLYFUSER Radial Leaded Resettable
PTC
From: "marcausman" <marc(at)verticalpower.com>
Date: Jan 05, 2010
"Probably" ? -------- Marc Ausman http://www.verticalpower.com "Move up to a modern electrical system" RV-7 IO-390 Flying Read this topic online here: http://forums.matronics.com/viewtopic.php?p=280320#280320 ________________________________________________________________________________
From: "Bob McCallum" <robert.mccallum2(at)sympatico.ca>
Subject: RE: [AeroElectric-List] Questions about circuit
protection
Date: Jan 05, 2010
Carlos; Different "Bob" here, but I must disagree with your viewpoint. Please see embedded comments. _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Carlos Trigo Sent: Tuesday, January 05, 2010 8:00 PM Subject: AeroElectric-List: RE: [AeroElectric-List] Questions about circuit protection Bob I really don't want to resuscitate this discussion but, even being aware of the technical advantages of fuses versus circuit breakers, it is indeed almost impossible to convince a pilot that a fuse is better than a circuit breaker. Why?? Fuse is simpler, less expensive, probably neater, and serves its intended purpose admirably. I've been a pilot for 35 years, a builder for only 5 and I much prefer the simplicity and economy of fuses. I consider myself a pilot first and I don't need convincing, I know fuses are better. (At least in my own mind they are) In flight, when a fuse blows, the pilot will hardly notice it, and even if some device (whose circuit was protected by that fuse) becomes blank, he will not know if it was the fuse or anything else that caused that device to die. And how is that any different than the symptoms presented by a tripped breaker? The supplied device ceases to function in either case. To the pilot operating the aircraft there is no difference, he looses the benefit of whatever widget was supplied power by that circuit. If a circuit breaker pops out, there is a big probability the pilot will immediately notice it, How or why will he notice it?? and why does it matter?? or at least after seeing any device die, he will immediately look to the circuit breakers heads to look for the one that popped out. Are you making the assumption that the breakers are somehow readily available, visible and accessible in flight?? What if the breakers are neatly hidden away up under the panel, are on a fold down bracket, or in some other manner not readily apparent to the pilots position or his line of sight? What if the breaker that faults is one on the battery buss, hidden away in the tail cone next the battery? How does that present some different scenario to the pilot than would a fuse?? Being a pilot trained for so many things, he must also know that he shall not push that particular breaker in, unless he wants to light up the fire which will burn his own ass. All the more reason for, and another demonstration of, the superiority of hidden fuses. (Or hidden breakers for that matter) Removes the temptation and doesn't require the discipline and willpower "not to reset". It is probably easy to convince an aircraft builder to prefer fuses, but since in the OBAM world we are builders AND pilots, circuit breakers are certainly much more user friendly for the pilot, even knowing that the PILOT is the most dangerous single-point-of-failure in a flying aircraft I really fail to see the "user friendly" analogy. The fuses in all the cars I've owned have been about as "user friendly" as I can imagine, and in some of my cars I never had occasion to even learn where they were. Can't remember the last time one ever blew. In the dozen or so types of aircraft I'm checked out in, I can't remember the last time a fuse blew, or a breaker tripped either. In a properly designed and functioning car or aircraft, I wouldn't "expect" the circuit protection devices to be called upon to do their job for the life of the vehicle, be it airborne or ground based. I fully agree with the "insurance" provided by their presence, but wouldn't expect them to be called upon. (If breakers are somehow superior, why do the millions of cars on the road use fuses?) As Bob explained the main reason aircraft migrated to expensive breakers was to mitigate the drawbacks of "old" technology glass cartridge fuses such as loose retaining caps and low pressure contacts prone to corrosion. We now have modern "blade" fuses without these shortcomings. Don't get me wrong, I fully understand and respect your opinion and viewpoint, I just can't get a grasp on the logic behind it. As one who makes a living as an engineer, I view simple as better and fuses are simpler and less expensive than breakers and have much less chance of having something go wrong with them which makes the pilot side of me much more relaxed and comfortable with fuses than breakers. Carlos Respectfully, Bob McC ________________________________________________________________________________
Subject: Re: Question about 16V POLYFUSER Radial Leaded Resettable
PTC
From: "al38kit" <alfranken(at)msn.com>
Date: Jan 05, 2010
I have an EXP bus that I have been considering for my project. (That I got for a $40, delivered.) It looks like a slick unit. I can understand the concern for a circuit resetting itself after the power is restored...but isn't that a reason we put switches on things?...Like leave that circuit off if it has a problem... Sorry, just don't see the design as having much of a downside. If you think you may accidentally turn the thing back on, put some red tape on the switch or something...pull the wire. Al Read this topic online here: http://forums.matronics.com/viewtopic.php?p=280326#280326 ________________________________________________________________________________
From: "Jared Yates" <junk(at)jaredyates.com>
Subject: RE: [AeroElectric-List] Questions about circuit
protection
Date: Jan 06, 2010
In some of the larger factory-made airplanes, the breakers are situated behind the pilot's head. In this location popped breakers are only obvious if you get up out of your seat to look. It's pretty embarrassing to call the maintenance guys, go through some diagnostics on a non-functioning gadget, then have them instruct you to pull the breaker and doh! It was popped all along. One time I tried to extend the flaps for landing, but they didn't extend because all 5 of the flap motor circuit breakers have been pulled since before takeoff. In that case the mechanics were working on the flaps, pulled the breakers as a normal safety measure, but then forgot to put them in when they were done. Then two pilots didn't notice that they were out, at least not until configuring for the landing. In that airplane the normal flap setting for takeoff was zero. I can think of several other similar stories that illustrate that popped breakers aren't necessarily all that obvious. Once you realize that something isn't working and start looking for a breaker, they might be more obvious than a fuse, unless you spend the extra cents on the bling-bling LED fuses. _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bob McCallum Sent: Tuesday, January 05, 2010 11:11 PM Subject: RE: AeroElectric-List: RE: [AeroElectric-List] Questions about circuit protection Carlos; Different "Bob" here, but I must disagree with your viewpoint. Please see embedded comments. _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Carlos Trigo Sent: Tuesday, January 05, 2010 8:00 PM Subject: AeroElectric-List: RE: [AeroElectric-List] Questions about circuit protection Bob I really don't want to resuscitate this discussion but, even being aware of the technical advantages of fuses versus circuit breakers, it is indeed almost impossible to convince a pilot that a fuse is better than a circuit breaker. Why?? Fuse is simpler, less expensive, probably neater, and serves its intended purpose admirably. I've been a pilot for 35 years, a builder for only 5 and I much prefer the simplicity and economy of fuses. I consider myself a pilot first and I don't need convincing, I know fuses are better. (At least in my own mind they are) In flight, when a fuse blows, the pilot will hardly notice it, and even if some device (whose circuit was protected by that fuse) becomes blank, he will not know if it was the fuse or anything else that caused that device to die. And how is that any different than the symptoms presented by a tripped breaker? The supplied device ceases to function in either case. To the pilot operating the aircraft there is no difference, he looses the benefit of whatever widget was supplied power by that circuit. If a circuit breaker pops out, there is a big probability the pilot will immediately notice it, How or why will he notice it?? and why does it matter?? or at least after seeing any device die, he will immediately look to the circuit breakers heads to look for the one that popped out. Are you making the assumption that the breakers are somehow readily available, visible and accessible in flight?? What if the breakers are neatly hidden away up under the panel, are on a fold down bracket, or in some other manner not readily apparent to the pilots position or his line of sight? What if the breaker that faults is one on the battery buss, hidden away in the tail cone next the battery? How does that present some different scenario to the pilot than would a fuse?? Being a pilot trained for so many things, he must also know that he shall not push that particular breaker in, unless he wants to light up the fire which will burn his own ass. All the more reason for, and another demonstration of, the superiority of hidden fuses. (Or hidden breakers for that matter) Removes the temptation and doesn't require the discipline and willpower "not to reset". It is probably easy to convince an aircraft builder to prefer fuses, but since in the OBAM world we are builders AND pilots, circuit breakers are certainly much more user friendly for the pilot, even knowing that the PILOT is the most dangerous single-point-of-failure in a flying aircraft I really fail to see the "user friendly" analogy. The fuses in all the cars I've owned have been about as "user friendly" as I can imagine, and in some of my cars I never had occasion to even learn where they were. Can't remember the last time one ever blew. In the dozen or so types of aircraft I'm checked out in, I can't remember the last time a fuse blew, or a breaker tripped either. In a properly designed and functioning car or aircraft, I wouldn't "expect" the circuit protection devices to be called upon to do their job for the life of the vehicle, be it airborne or ground based. I fully agree with the "insurance" provided by their presence, but wouldn't expect them to be called upon. (If breakers are somehow superior, why do the millions of cars on the road use fuses?) As Bob explained the main reason aircraft migrated to expensive breakers was to mitigate the drawbacks of "old" technology glass cartridge fuses such as loose retaining caps and low pressure contacts prone to corrosion. We now have modern "blade" fuses without these shortcomings. Don't get me wrong, I fully understand and respect your opinion and viewpoint, I just can't get a grasp on the logic behind it. As one who makes a living as an engineer, I view simple as better and fuses are simpler and less expensive than breakers and have much less chance of having something go wrong with them which makes the pilot side of me much more relaxed and comfortable with fuses than breakers. Carlos Respectfully, Bob McC ________________________________________________________________________________
From: "Jay Hyde" <jay(at)horriblehyde.com>
Subject: Re: Battery Bus Location
Date: Jan 06, 2010
I put one of my battery busses on the hot side of the firewall and the other on the cold side (2 batteries). My reasoning was that I would rather have the connection between the buss and the battery short on the hot side than lead the wire to the cold side. For the second battery, which is located in the cargo compartment, I had to lead a long fat wire to the front, as per my previous mail. The battery bus is located where the fat wire ends at the firewall, on the contactor for that battery. As Bob pointed out, this is not ideal as it means that you have a long fat wire (now protected by an inline fuse as described in my last mail) between the battery and the contactor. The rational for this is that the routing between the front and back is not easy and I would rather have 1 mechanically robust wire than several smaller wires that might be subject to chaffing and damage- the fat wire is much easier to protect mechanically. Not ideal, but adapted to the situation that I have... Jay -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: 06 January 2010 01:30 AM Subject: Re: AeroElectric-List: Re: Battery Bus Location At 04:10 PM 1/5/2010, you wrote: > >Bob, >Thanks for the reply. I'm not opposed to putting it outside on the >firewall, I just didn't know whether the fuse blocks from B&C would >be alright out there. I think you spell out 6" length on the feed wire. That's an idealized notion. If you need to make it 12" or even longer to satisfy design goals, the world is not going to come to an end. > If I stick to that, which makes sense unprotected, then I would > have to put it directly on the inside of the firewall which would > be extremely difficult to get to for service. Hopefully none will > be required, but it would be easier on the hot side. Then put it in a location for ease of maintenance. That would be my choice as well. Think about a way to at least cover if not box-up the fuseblock like they do under the hood of cars. >The insulator would indeed be a good method to get the wire inside, >but the length is still a factor. The length isn't a REALLY BIG thing, just a good practice design rule adopted by the TC side of the house many years ago. How long would the wire be for both extending the battery feeder AND ease of maintenance? >Does most everyone else put them on the hot side? Good question. How about it guys? Anyone out there flying fuse blocks on the forward side of the firewall? Bob . . . ________________________________________________________________________________
From: "Jay Hyde" <jay(at)horriblehyde.com>
Subject: RE: [AeroElectric-List] Questions about circuit
protection
Date: Jan 06, 2010
I use fuses for my designs as well and add what I call a FAP (Fuse Annunciator Panel) which is an array of LED's that are connected to the 'downsteam' side of the fuse. By pressing a common pushbutton that connects all of the LED's to ground I can immediately see whether all of the fuses are OK. For the pilot this is great- press the button on the pre-flight and the status of all the fuses is shown; and in flight they can check the fuses the same way if there is some suspicion that a fuse has blown. It requires some extra PT with the wiring but I am working on a fuse holder that will make this much easier. My first version was a bit clumsy, but they're getting better. I even have a light test button. :-) Jay _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jared Yates Sent: 06 January 2010 08:16 AM Subject: RE: AeroElectric-List: RE: [AeroElectric-List] Questions about circuit protection In some of the larger factory-made airplanes, the breakers are situated behind the pilot's head. In this location popped breakers are only obvious if you get up out of your seat to look. It's pretty embarrassing to call the maintenance guys, go through some diagnostics on a non-functioning gadget, then have them instruct you to pull the breaker and doh! It was popped all along. One time I tried to extend the flaps for landing, but they didn't extend because all 5 of the flap motor circuit breakers have been pulled since before takeoff. In that case the mechanics were working on the flaps, pulled the breakers as a normal safety measure, but then forgot to put them in when they were done. Then two pilots didn't notice that they were out, at least not until configuring for the landing. In that airplane the normal flap setting for takeoff was zero. I can think of several other similar stories that illustrate that popped breakers aren't necessarily all that obvious. Once you realize that something isn't working and start looking for a breaker, they might be more obvious than a fuse, unless you spend the extra cents on the bling-bling LED fuses. _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Bob McCallum Sent: Tuesday, January 05, 2010 11:11 PM Subject: RE: AeroElectric-List: RE: [AeroElectric-List] Questions about circuit protection Carlos; Different "Bob" here, but I must disagree with your viewpoint. Please see embedded comments. _____ From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Carlos Trigo Sent: Tuesday, January 05, 2010 8:00 PM Subject: AeroElectric-List: RE: [AeroElectric-List] Questions about circuit protection Bob I really don't want to resuscitate this discussion but, even being aware of the technical advantages of fuses versus circuit breakers, it is indeed almost impossible to convince a pilot that a fuse is better than a circuit breaker. Why?? Fuse is simpler, less expensive, probably neater, and serves its intended purpose admirably. I've been a pilot for 35 years, a builder for only 5 and I much prefer the simplicity and economy of fuses. I consider myself a pilot first and I don't need convincing, I know fuses are better. (At least in my own mind they are) In flight, when a fuse blows, the pilot will hardly notice it, and even if some device (whose circuit was protected by that fuse) becomes blank, he will not know if it was the fuse or anything else that caused that device to die. And how is that any different than the symptoms presented by a tripped breaker? The supplied device ceases to function in either case. To the pilot operating the aircraft there is no difference, he looses the benefit of whatever widget was supplied power by that circuit. If a circuit breaker pops out, there is a big probability the pilot will immediately notice it, How or why will he notice it?? and why does it matter?? or at least after seeing any device die, he will immediately look to the circuit breakers heads to look for the one that popped out. Are you making the assumption that the breakers are somehow readily available, visible and accessible in flight?? What if the breakers are neatly hidden away up under the panel, are on a fold down bracket, or in some other manner not readily apparent to the pilots position or his line of sight? What if the breaker that faults is one on the battery buss, hidden away in the tail cone next the battery? How does that present some different scenario to the pilot than would a fuse?? Being a pilot trained for so many things, he must also know that he shall not push that particular breaker in, unless he wants to light up the fire which will burn his own ass. All the more reason for, and another demonstration of, the superiority of hidden fuses. (Or hidden breakers for that matter) Removes the temptation and doesn't require the discipline and willpower "not to reset". It is probably easy to convince an aircraft builder to prefer fuses, but since in the OBAM world we are builders AND pilots, circuit breakers are certainly much more user friendly for the pilot, even knowing that the PILOT is the most dangerous single-point-of-failure in a flying aircraft I really fail to see the "user friendly" analogy. The fuses in all the cars I've owned have been about as "user friendly" as I can imagine, and in some of my cars I never had occasion to even learn where they were. Can't remember the last time one ever blew. In the dozen or so types of aircraft I'm checked out in, I can't remember the last time a fuse blew, or a breaker tripped either. In a properly designed and functioning car or aircraft, I wouldn't "expect" the circuit protection devices to be called upon to do their job for the life of the vehicle, be it airborne or ground based. I fully agree with the "insurance" provided by their presence, but wouldn't expect them to be called upon. (If breakers are somehow superior, why do the millions of cars on the road use fuses?) As Bob explained the main reason aircraft migrated to expensive breakers was to mitigate the drawbacks of "old" technology glass cartridge fuses such as loose retaining caps and low pressure contacts prone to corrosion. We now have modern "blade" fuses without these shortcomings. Don't get me wrong, I fully understand and respect your opinion and viewpoint, I just can't get a grasp on the logic behind it. As one who makes a living as an engineer, I view simple as better and fuses are simpler and less expensive than breakers and have much less chance of having something go wrong with them which makes the pilot side of me much more relaxed and comfortable with fuses than breakers. Carlos Respectfully, Bob McC http://www.matronics.com/Navigator?AeroElectric-List http://forums.matronics.com http://www.matronics.com/contribution ________________________________________________________________________________
From: "Neal George" <n8zg(at)mchsi.com>
Subject: Re: Question about 16V POLYFUSER Radial Leaded
Resettable PTC
Date: Jan 06, 2010
No sir. We put switches on electrical circuits to provide On/Off control of the load under normal operations. Once an overload condition manifests, operations are no longer normal. Powering a circuit that you know has experienced an overload invites smoke, flame and fury in a confined space with no reasonable exit. War story follows: Standing nuclear alert in the missile fields around Cheyenne, WY, our procedures allowed ONE attempt to reset a tripped circuit breaker, after a specified cool-down period. Smoke in the capsule is bad, and getting out is neither easy nor quick. Neal I can understand the concern for a circuit resetting itself after the power is restored...but isn't that a reason we put switches on things?...Like leave that circuit off if it has a problem... Sorry, just don't see the design as having much of a downside. If you think you may accidentally turn the thing back on, put some red tape on the switch or something...pull the wire. Al ________________________________________________________________________________
From: "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net>
Subject: RE: [AeroElectric-List] Questions about circuit
protection
Date: Jan 06, 2010
Bob I really don't want to resuscitate this discussion but, even being aware of the technical advantages of fuses versus circuit breakers, it is indeed almost impossible to convince a pilot that a fuse is better than a circuit breaker. In flight, when a fuse blows, the pilot will hardly notice it, and even if some device (whose circuit was protected by that fuse) becomes blank, he will not know if it was the fuse or anything else that caused that device to die. If a circuit breaker pops out, there is a big probability the pilot will immediately notice it, or at least after seeing any device die, he will immediately look to the circuit breakers heads to look for the one that popped out. Being a pilot trained for so many things, he must also know that he shall not push that particular breaker in, unless he wants to light up the fire which will burn his own ass. It is probably easy to convince an aircraft builder to prefer fuses, but since in the OBAM world we are builders AND pilots, circuit breakers are certainly much more user friendly for the pilot, even knowing that the PILOT is the most dangerous single-point-of-failure in a flying aircraft Carlos .Two simple examples: 1) You are flying along in your airplane with circuit breakers, the radio goes dead, and a breaker button pops out. What do you do? Fly the airplane!! 2) You are flying along in your airplane with Fuses, the radio goes dead, and nothing else happens. What do you do? Fly the airplane!! When you get on the ground you troubleshoot the problem. If the added cost for the row of little buttons to pop out, on the dash, gives you a sense of security, I say GO FOR IT...... rOGER ________________________________________________________________________________
From: "Carlos Trigo" <trigo(at)mail.telepac.pt>
Subject: RE: [AeroElectric-List] Questions about circuit
protection
Date: Jan 06, 2010
.Two simple examples: 1) You are flying along in your airplane with circuit breakers, the radio goes dead, and a breaker button pops out. What do you do? Fly the airplane, knowing that something happened in the electric circuit that is protected by that particular circuit breaker. If the radio (or anything else that went dead) is not critical to your flight, you complete it with no other worries 2) You are flying along in your airplane with Fuses, the radio goes dead, and nothing else happens. What do you do? Fly the airplane!! not knowing what happened. Did I loose the alternator? Is there anything that is going to start a fire? What should I do? Should I land ASAP? Shall I declare an emergency? Next, anything can happen to the pilot, even panic When you get on the ground you troubleshoot the problem. If it was a fuse, it can take some time to find out which. If it was a circuit breaker, I will go IMMEDIATELY to the source of the problem If the added cost for the row of little buttons to pop out, on the dash, gives you a sense of security, I say GO FOR IT...... I have 1 airplane with fuses, 1 airplane with cb's, and the one I'm finishing building have both. Not biased, though. :-) Only analysing pros and cons. Carlos ________________________________________________________________________________
Subject: Re: Question about 16V POLYFUSER Radial Leaded Resettable
PTC
From: "al38kit" <alfranken(at)msn.com>
Date: Jan 06, 2010
Neal...having spent some time in the military myself, I know there is ofter not much thinking that is to be done, and a procedure for almost everything... That being said and that we are no longer held to that kind of procedure, what's the down side to leaving the switch off? No one says you have to reset it. My understanding is that once the electrons are removed from the circuit, it's dead. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=280355#280355 ________________________________________________________________________________
Subject: Re: Battery Bus Location
From: "PaulR" <prose(at)panhandle.rr.com>
Date: Jan 06, 2010
[/quote] The length isn't a REALLY BIG thing, just a good practice design rule adopted by the TC side of the house many years ago. How long would the wire be for both extending the battery feeder AND ease of maintenance? I think i could get by with 18-24" depending on how "easily maintainable" it is. While it's really too cold to heat the shop up for a couple hours, I think I'll see if I can find a covered fuse block until I'm back in the shop over the weekend -------- Paul Rose N417PR (res) RV-9A Read this topic online here: http://forums.matronics.com/viewtopic.php?p=280358#280358 ________________________________________________________________________________
Date: Jan 06, 2010
From: Dennis Golden <dgolden@golden-consulting.com>
Subject: Re: Question about 16V POLYFUSER Radial Leaded
Resettable PTC al38kit wrote: > > Neal...having spent some time in the military myself, I know there is ofter not much thinking that is to be done, and a procedure for almost everything... > > That being said and that we are no longer held to that kind of procedure, what's the down side to leaving the switch off? > > No one says you have to reset it. > > My understanding is that once the electrons are removed from the circuit, it's dead. What if the fault IS the switch, or the wiring going TO the switch. Dennis -- Dennis Golden Golden Consulting Services, Inc. ________________________________________________________________________________
Date: Jan 06, 2010
From: Dan Brown <dan(at)familybrown.org>
Subject: RE: [AeroElectric-List] Questions about circuit
protection Quoting Carlos Trigo : > 2) You are flying along in your airplane with Fuses, the radio goes dead, > and nothing else happens. What do you do? Fly the airplane!! not knowing > what happened. Did I loose the alternator? Is there anything that is going > to start a fire? What should I do? Should I land ASAP? Shall I declare an > emergency? Next, anything can happen to the pilot, even panic Losing the alternator won't take out the radio, unless you don't have a battery (in which case it will take out everything electrical). Losing the alternator will, however, activate the low-voltage warning that you have installed (don't you?), letting you know that you're running on battery power. If you're panicking (as most of your questions sound like) over losing one radio, you probably shouldn't be a pilot. > When you get on the ground you troubleshoot the problem. If it was a fuse, > it can take some time to find out which. If it takes you more than 30 seconds to find which fuse goes to that radio, you haven't designed or labeled your electrical system very well. -- Dan Brown, KE6MKS, dan(at)familybrown.org "Since all the world is but a story, it were well for thee to buy the more enduring story rather than the story that is less enduring." -- The Judgment of St. Colum Cille ________________________________________________________________________________
Subject: Z-14 Switch Combos
Date: Jan 06, 2010
From: "Perry, Phil" <Phil.Perry(at)netapp.com>
Hey Bob, It looks like the crossfeed switch doubles as a starter switch in your diagram, is that correct? I'm planning on going with a push button to start, so I'll probably modify the setup slightly. But just want to make sure I'm reading it correctly. Thanks, Phil -----Original Message----- From: Robert L. Nuckolls, III [mailto:nuckolls.bob(at)aeroelectric.com] Sent: Tuesday, January 05, 2010 9:29 AM Subject: RE: AeroElectric-List: Z-14 Switch Combos At 09:08 PM 1/4/2010, you wrote: > >Phil - > >I think you misinterpreted Bob's comment. It appears you read it to say >"you're never ALLOWED to close the cross-feed switch", when Bob meant "you >might not ever have a reason to close it". > >Neal Correct. The process for deciding how to operate Z-14 is dependent upon what devices are fed from each bus and how you use the airplane. Z-14 was originally crafted for a guy building a Glasair with full up IFR capability in both seats. Further, it was the builder's intent to use this machine in missions that most of us work hard to avoid. Z-14 offers OPTIONS for deciding how you will manage energy resources that have become limited due to failure of some component like an alternator or battery contactor. There is no SET PROCEDURE I can offer you without doing the same failure modes effects analysis I would conduct for a TC aircraft with a similar system installed and tailored to the most demanding mission for which the airplane is outfitted. Z-14's cross-feed contactor solved a problem with attempting to PARALLEL two alternators in a dual alternator airplane by making them responsible for SEPARATE systems in normal operations. Z-13/8 was crafted to take exploit the existence of an unused engine accessory drive pad when a vacuum pump is removed. Some politicians hate to waste a good crisis, I had to waste a good drive pad. When considered against the quantum jumps in reliability offered by modern alternators and artfully maintained RG batteries, I believe Z-13/8 is about the most elegant solution to powering up the light airplane for 99 plus percent of all OBAM aircraft. If you have Z-14 installed, then share with us how equipment in your airplane is powered from the two busses along with your vision of how you expect to use this airplane. Is it important to you to forestall a dark-n-stormy night story 'cause you've had an alternator go belly up while night IFR over the Rockies crossing a weather front? If so, what items of equipment are installed and how are they spread between the two systems? Bob . . . ________________________________________________________________________________
Date: Jan 06, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Z-14 Switch Combos
At 10:19 AM 1/6/2010, you wrote: > >Hey Bob, > >It looks like the crossfeed switch doubles as a starter switch in your >diagram, is that correct? Yes . . . it's spring loaded out of the start position. It offers automatic closure of the cross-feed contactor during start. >I'm planning on going with a push button to start, so I'll probably >modify the setup slightly. But just want to make sure I'm reading it >correctly. Then the cross-feed switch can be SPST. Bob . . . ________________________________________________________________________________
Date: Jan 06, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: RE: [AeroElectric-List] Questions about circuit
protection At 07:00 PM 1/5/2010, you wrote: >Bob > >I really don=92t want to resuscitate this >discussion but, even being aware of the >technical advantages of fuses versus circuit >breakers, it is indeed almost impossible to >convince a pilot that a fuse is better than a circuit breaker. It has never been offered as 'better' . . . only adequate to the task of meeting design goals in a failure tolerant system. >In flight, when a fuse blows, the pilot will >hardly notice it, and even if some device (whose >circuit was protected by that fuse) becomes >blank, he will not know if it was the fuse or >anything else that caused that device to die. Have you read . . . http://www.aeroelectric.com/articles/fusvbkr2.html >If a circuit breaker pops out, there is a big >probability the pilot will immediately notice >it, or at least after seeing any device die, he >will immediately look to the circuit breakers >heads to look for the one that popped out. >Being a pilot trained for so many things, he >must also know that he shall not push that >particular breaker in, unless he wants to light >up the fire which will burn his own ass=85 It's not clear that you embrace/understand the rationale presented for unreachable fuse-blocks. Certainly everyone has a choice to make and in the final analysis it's personal. I did a power distribution diagram for the BD-10 jet about 15 years ago. I bounced the idea of fuse-blocks off the electrical systems wienie. He agreed that they were adequate to the task but opined that anyone building a BD-10 wanted that "busy fighter cockpit look. The more knobs, buttons and switches the better." But even after the drawing was completed using breakers throughout, he about had a cow when I put about a dozen breakers back in the engine compartment. The architecture called for protection in these feeders and the sources for those feeders were in the tail. Further, there was no failure mode effects analysis that supported any need for pilot access to these breakers whatsoever. Nonetheless, he insisted on having all breakers in the cockpit. I submitted my bill for work accomplished to date and bowed out of the project. Got a nastygram from Mr. Bede hisself honking about the fee and stating that his electro-wienie wasn't authorized to make contracts. I settled for 50 cents on the dollar and chalked it up to the fates. Have you identified errors in the logic offered in many published pieces on the website and here on the List that speak to suitability of fuses? If not, then like the BD-10 episode, it's a matter of preference. Breakers and their panels are not unsafe. They're only heavier, more expensive, take up panel space, require hours of fabrication time, restrict wire bundle routing options, offer no enhanced level of safety and MAY be distracting to a pilot who should be doing more important things. But if one chooses breakers, they're in good company. The vast majority of the GA fleet is carrying tons of them around the sky with a vanishingly small probability that any single breaker will ever be called upon to do its job. Bob . . . ________________________________________________________________________________
Date: Jan 06, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Battery Bus Location
At 10:00 AM 1/6/2010, you wrote: > >[/quote] > The length isn't a REALLY BIG thing, just a > good practice design rule adopted by the TC > side of the house many years ago. How long would > the wire be for both extending the battery > feeder AND ease of maintenance? > > I think i could get by with 18-24" depending on how "easily > maintainable" it is. > >While it's really too cold to heat the shop up for a couple hours, I >think I'll see if I can find a covered fuse block until I'm back in >the shop over the weekend Think about building a cover. The fuse-blocks mount with 4 screws. The "nut" for each of those fasteners could be a thru-hole, threaded spacer of sufficient height to just clear the tops of the fuses. Four thumb-nut screws would be used to mount the cover down to the tops of the spacers. A cover might be nothing more than a sheet with four folded down edges having notches for clearing wire bundles. I've been thinking about having some ABS covers made. A friend of mine does deep vacuum forming as a part of his manufacturing operations. Another option is to make the cover out of copper clad. See: http://www.aeroelectric.com/articles/cladboard/cladboard.html http://aeroelectric.com/Pictures/Data_Acquisition/Weeder_Module_DAS_1.jpg http://aeroelectric.com/Pictures/Data_Acquisition/Weeder_Module_DAS_2.jpg I've built robust enclosures out of this stuff. You only need to cut some accurate rectangular pieces, fixture them against square corners for soldering, run a bead of solder down the inside corner for assembly. Single sided clad gives you a fiberglas/epoxy outside surface that takes paint very nicely. Bob . . . ________________________________________________________________________________
Date: Jan 06, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Battery Bus Location
> I would rather >have 1 mechanically robust wire than several smaller wires that might be >subject to chaffing and damage- the fat wire is much easier to protect >mechanically. Not ideal, but adapted to the situation that I have... The legacy rationale for incorporating an always hot wire into an airframe recognizes the limited ability of circuits protected at 5A or less to start post-crash fires. Extending the battery bus on a long feeder calls for protection of that feeder at some current level larger (and SLOWER) than total draw of accessories fed by the battery bus. Further, one should consider the dynamics of interaction between fuses at the bus and protection at the source end of the feeder. Bus feeders are generally CURRENT LIMITERS with high tolerance to overload. If a fast fuse is used upstream of a bus of fast fuses, one needs to make sure that popping a bus fuse doesn't take the upstream fuse too. Remember that the upstream fuse is "pre-heated" by total loads on the battery bus. Faulting one of the 5A fuses on the bus could trip a 20A feeder protection and take the whole bus down. When the case is finally adjudicated, I'll be able to share how a stack-up of "little details" about fault- trip dynamics brought down a nearly new, very expensive airplane while getting folks hurt in the process. If the battery bus is back in the tail, then any feeders coming forward don't need extra-ordinary protection. They're lightly fused and risks for faulting any single feeder are low. Once the bus feeder turns into a fat wire, the legacy design philosophy for always hot wires is worthy of consideration. Bob . . . ________________________________________________________________________________
Date: Jan 06, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Tachometer problems
>Could anyone suggest some specific combination of >capacitor/resistor/diode inline or parallel to the tacho I could try >to smooth things out? Failed to get any help from VDO so any >advice would be very much appreciated. It's a WAG. Without knowing how the input circuits of the tachometer are crafted, then it's VERY difficult to figure out what it doesn't like about the signal


December 24, 2009 - January 06, 2010

AeroElectric-Archive.digest.vol-jf