---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 03/08/09: 16 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 08:05 AM - Re: Re: Wiring / Relay Question (Henry Trzeciakowski) 2. 09:48 AM - Anti-rotation washers for thermocouple switch? (Steve Stearns) 3. 10:05 AM - Re: ACS's Lightsaver gadget (Steve Stearns) 4. 12:43 PM - Wingtip Nav question (Tim Olson) 5. 01:13 PM - Re: Wingtip Nav question (Richard E. Tasker) 6. 01:13 PM - Re: ACS's Lightsaver gadget (Robert L. Nuckolls, III) 7. 01:16 PM - Re: Re: Wiring / Relay Question (Robert L. Nuckolls, III) 8. 01:42 PM - Re: Wingtip Nav question (Etienne Phillips) 9. 01:48 PM - Re: Anti-rotation washers for thermocouple switch? (Robert L. Nuckolls, III) 10. 01:48 PM - Re: Anti-rotation washers for thermocouple switch? (Robert L. Nuckolls, III) 11. 04:03 PM - Re: Wingtip Nav question (Robert L. Nuckolls, III) 12. 04:48 PM - Re: Plasma III Wiring Again! () 13. 05:55 PM - Re: Wingtip Nav question (Richard E. Tasker) 14. 07:58 PM - Looking for cover photo . . . (Robert L. Nuckolls, III) 15. 08:22 PM - Re: What is a ON-ON-ON switch used for? (rparigor@SUFFOLK.LIB.NY.US) 16. 10:08 PM - Re: Wingtip Nav question (Etienne Phillips) ________________________________ Message 1 _____________________________________ Time: 08:05:36 AM PST US From: "Henry Trzeciakowski" Subject: Re: AeroElectric-List: Re: Wiring / Relay Question Bob: Sorry for the confusion: My battery bus IS firewall forward under the cowl. Looking at your Z-32 (Heavy Duty E-Bus Feed), I missed the "*" that represents the 6 inch rule. My mounting is : Battery Bus (under cowl)------(14awg )---FIREWALL ---- (14 awg)----s704-1 relay----to E-bus switch & E-Bus ( this run is about 2 1/2 feet from Battery Bus to Relay) I just need to ask the question - what harm would it be if I just left my runs as depicted above. I am fused (15 amp) on the Battery side, so my firewall penetration is protected. Or am I missing some other caveat ?? Henry ----- Original Message ----- From: "Robert L. Nuckolls, III" Sent: Wednesday, March 04, 2009 5:59 AM Subject: Re: AeroElectric-List: Re: Wiring / Relay Question > > At 02:50 PM 3/1/2009, you wrote: > > > > > >Bob > > > >I've placed my Battery Bus Firewall forward next to the Battery Contactor, > >just above the 60 amp current limiter. I have a 14 g (15 amp) wire going > >from battery bus thru firewall to a 7104 relay, as per the Heavy Duty E bus > >configuration. > > I'm not sure I'm seeing a good mental image of > your installation. I presume the 60A limiter is > your b-lead protection, normally this goes next > to the starter contactor which is usually on > the upper port corner of the firewall co-located > with a loadmeter shunt (if you have one). > > > >My question, should I use an additional relay or "something" between the > >Battery Bus (15amp - 14 g wire)-firewall forward - and the relay which is > >next to my E-Bus - mounted on sub-panel - for added safety? > > If you have a relay mounted next to the e-bus > inside the aircraft, then you have it on the wrong > end of the wire. The purpose of the e-bus > alternate feed relay is to serve as a sort of > mini-battery contactor for this feed line . . . > it should be mounted as close as practical > to the battery bus fuse that feeds it. > > Do I interpret correctly that your battery bus > is under the cowl? > > > Bob . . . > > ----------------------------------------) > ( . . . a long habit of not thinking ) > ( a thing wrong, gives it a superficial ) > ( appearance of being right . . . ) > ( ) > ( -Thomas Paine 1776- ) > ---------------------------------------- > > ________________________________ Message 2 _____________________________________ Time: 09:48:52 AM PST US From: Steve Stearns Subject: AeroElectric-List: Anti-rotation washers for thermocouple switch? Bob and Group, I'm using a pair of Grayhill GH5602s for thermocouple switching (per a link from Bob) and they will be mounted onto a foam-core panel (Longeze...). I could really use a couple anti-rotation washers (a tab on the O.D. and two flats on the ID with a nominal 1/4" ID) but haven't found a source for them. I have tried similar washers with only a single flat on the ID and they do not constrain the switch rotation. Any suggestions? Steve Stearns Boulder/Longmont, Colorado CSA,EAA,IAC,AOPA,PE,ARRL,BARC (but ignorant none-the-less) Restoring (since 1/07): N45FC O235 Longeze Cothern/Friling CF1 (~1000 Hrs) Flying (since 9/86): N43732 A65 Taylorcraft BC12D ________________________________ Message 3 _____________________________________ Time: 10:05:43 AM PST US From: Steve Stearns Subject: Re: AeroElectric-List: ACS's Lightsaver gadget Interesting traces Bob, What do you think would have the better reliability in the field for a 150W halogen landing light (without a surge suppressor), A S704-1 relay with an ~16V transient suppressor for the catch diode, or a S701-1 switch connecting directly to the lamp? I'm not sure how to trade off the bigger contacts, but they bounce longer, dilemma... Steve Stearns Boulder/Longmont, Colorado CSA,EAA,IAC,AOPA,PE,ARRL,BARC (but ignorant none-the-less) Restoring (since 1/07): N45FC O235 Longeze Cothern/Friling CF1 (~1000 Hrs) Flying (since 9/86): N43732 A65 Taylorcraft BC12D > At 02:11 PM 3/7/2009, you wrote: > >> > >> > >> >If you look at switch ratings, when they are connected to a lamp >> >load, the rating is greatly reduced. This is because of the large >> >inrush currents when filaments are cold. The inrush current >> >limiters will help limit this current, boosting switch life. >> > >> >Vern >> > > Great point! . . . I missed this thought in my earlier posting. > Consider that when you "close" a switch, the contacts bounce > many times. See: > > http://www.aeroelectric.com/Pictures/Curves/switch_transition_S700-1.jpg > > This bounce and transition trace on a Carling toggle > shows about 1.8 mS to travel from one condition to the > other. When I spread that bounce out to count the closures > there was about 6-7 as I recall. Relays can be even worse. > The heavier their contacts, the worse they bounce. See: > > http://www.aeroelectric.com/Pictures/Curves/S704-1_Contact_Bounce_without_Diode.jpg > > http://www.aeroelectric.com/Pictures/Curves/S704-1_Contact_Bounce_with_Diode.jpg > > These two traces are for the contacts of the plastic 30A > relay (S704). These things bounce like Tigger at a > birthday party. > > What's more, all the bouncing happens in that very > tiny interval of high inrush for warming up the incandescent > lamp filament. This means that an 10A switch controlling > an 8A lamp sees perhaps a dozen or more 40A "hits" > every time you turn on a cold lamp. > > That's why lamp ratings on switches are so heavily > de-rated. If you want to put an inrush limiter on > you landing lights, do it for the switch . . . not > the lamp. > > Thanks for the heads-up Vern. > > Bob . . . > > ________________________________ Message 4 _____________________________________ Time: 12:43:16 PM PST US From: Tim Olson Subject: AeroElectric-List: Wingtip Nav question In the Bob archer antenna install guide, it says that: "If two VOR receivers are being installed one antenna should be installed in each wing tip and each antenna connected to a receiver. This type of installation would produce twice as much signal into each receiver and this much signal increase would mean an increase of about 25% increase in VOR range." Can someone explain how this could be so? Currently I have one in a wingtip and one on the tail, but due to some new antenna needs I may be moving my tail antenna. I don't understand how having one in each wingtip would affect performance, considering they're being connected to separate receivers, and each receiver may be tuned to whole separate VOR's. I just don't get how it could be. -- Tim Olson - RV-10 N104CD ________________________________ Message 5 _____________________________________ Time: 01:13:07 PM PST US From: "Richard E. Tasker" Subject: Re: AeroElectric-List: Wingtip Nav question What it is saying is to use two antennas (one per receiver), rather than one antenna with a splitter. Dick Tasker Tim Olson wrote: > > In the Bob archer antenna install guide, it says that: > > "If two VOR receivers are being installed one antenna > should be installed in each wing tip and each antenna > connected to a receiver. This type of installation > would produce twice as much signal into each receiver > and this much signal increase would mean an increase > of about 25% increase in VOR range." > > Can someone explain how this could be so? Currently > I have one in a wingtip and one on the tail, but due > to some new antenna needs I may be moving my tail > antenna. I don't understand how having one in each > wingtip would affect performance, considering they're > being connected to separate receivers, and each receiver > may be tuned to whole separate VOR's. > > I just don't get how it could be. > > -- Please Note: No trees were destroyed in the sending of this message. We do concede, however, that a significant number of electrons may have been temporarily inconvenienced. -- ________________________________ Message 6 _____________________________________ Time: 01:13:17 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: ACS's Lightsaver gadget At 01:03 PM 3/8/2009, you wrote: > >Interesting traces Bob, > >What do you think would have the better reliability in the field for >a 150W halogen landing light (without a surge suppressor), A S704-1 >relay with an ~16V transient suppressor for the catch diode, or a >S701-1 switch connecting directly to the lamp? >I'm not sure how to trade off the bigger contacts, but they bounce >longer, dilemma... Gee . . . you noticed! It's a credit to your curiosity combined with an awareness of the need for trade-offs. I an my contemporaries were faced with thousands of such questions over our careers . . . with input from a host of special interests that included marketing, purchasing, inventory management, manufacturing engineers and other systems guys who regarded every one else's specialty as witchcraft. Going for lower parts count is always a good lick. The 150W lamp presents a problem of sorts. It takes right at 9.5A in normal operation. But given what we know of a switch's ability to CARRY current after the bouncing is over, I'd bet that an S701 combined with a Cantherm MF72-3D25 inrush limiter (3 ohms cold) will limit your inrush to under 5 amps and toss off only 9 x .044 = 0.37 volts in operation. See: http://www.cantherm.com/products/thermistors/cantherm_mf72.pdf and http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=317-1234-ND This would be the lowest parts count solution I can deduce and I think it has a fair shot at satisfactory performance. I'll do some thinking about practical ways to mount the inrush limiter so that it is well supported, well connected, but not thermally deprived of the ability to warm up. In the GP-180, one of the guys crimped flexible leadwires to the part, wrapped it with a couple of layers of fiberglas door gasket for a wood burning stove and clamped the assembly into the inside surface of the Grimes lamp fixture housing. Kinda clumsy but it worked. Their first efforts took too much heat out of the thing which caused catastrophic stresses from power dissipation. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 7 _____________________________________ Time: 01:16:06 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Wiring / Relay Question At 01:08 PM 3/8/2009, you wrote: > > >Bob: > >Sorry for the confusion: > >My battery bus IS firewall forward under the cowl. Looking at your Z-32 >(Heavy Duty E-Bus Feed), I missed the "*" that represents the 6 inch rule. >My mounting is : > >Battery Bus (under cowl)------(14awg )---FIREWALL ---- (14 awg)----s704-1 >relay----to E-bus switch & E-Bus > ( this run is about 2 1/2 feet from >Battery Bus to Relay) > >I just need to ask the question - what harm would it be if I just left my >runs as depicted above. I am fused (15 amp) on the Battery side, so my >firewall penetration is protected. Or am I missing some other caveat ?? It would probably cause a bureaucrat with a rulebook to fuss but the risks are low for doing as you've suggested. I presume you have other wires coming through the firewall along with the e-bus feeder that are receiving due diligence with respect to wire protection and firewall integrity? Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 8 _____________________________________ Time: 01:42:31 PM PST US From: Etienne Phillips Subject: Re: AeroElectric-List: Wingtip Nav question 2 antennae on one receiver and transmitter is not as easy as it seems. You need to match the distance between the antennae to the frequency, and direction you expect to be receiving from... The length of cable inbetween the antennae is also important. Not for the faint of heart... Best case is a signal strength that is about 80% as good as 1 antenna from all directions. Worst case is that it's twice as potent in one direction, and completely dead 90 degrees out. Unless you're trying to make a directional antennae array in which case the best and worst cases swap around! For navigation, I like non-directional antennae :-) With this in mind, I have no idea what the install guide is referring to. It may be that placing two non-connected VOR antennae right next to each other causes them to interfere with one another, and by mounting them as far apart as possible (on either wingtip) the detrimental effects are halved. On 08 Mar 2009, at 10:10 PM, Richard E. Tasker wrote: > > > What it is saying is to use two antennas (one per receiver), rather > than one antenna with a splitter. > > Dick Tasker > ________________________________ Message 9 _____________________________________ Time: 01:48:56 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Anti-rotation washers for thermocouple switch? >I'm using a pair of Grayhill GH5602s for thermocouple switching >(per a link from Bob) and they will be mounted onto a foam-core >panel (Longeze...). I could really use a couple anti-rotation >washers (a tab on the O.D. and two flats on the ID with a nominal >1/4" ID) but haven't found a source for them. I have tried similar >washers with only a single flat on the ID and they do not constrain >the switch rotation. > >Any suggestions? Sure. Page 13 of http://www.aeroelectric.com/Mfgr_Data/Switches/Grayhill/56_Rotary.pdf shows part number 50J1066 as suited to this purpose. Digikey has the part in the catalog at: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=50J1066-ND but currently out of stock. Expected ship date later this month. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 10 ____________________________________ Time: 01:48:56 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Anti-rotation washers for thermocouple switch? >I'm using a pair of Grayhill GH5602s for thermocouple switching >(per a link from Bob) and they will be mounted onto a foam-core >panel (Longeze...). I could really use a couple anti-rotation >washers (a tab on the O.D. and two flats on the ID with a nominal >1/4" ID) but haven't found a source for them. I have tried similar >washers with only a single flat on the ID and they do not constrain >the switch rotation. > >Any suggestions? Sure. Page 13 of http://www.aeroelectric.com/Mfgr_Data/Switches/Grayhill/56_Rotary.pdf shows part number 50J1066 as suited to this purpose. Digikey has the part in the catalog at: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=50J1066-ND but currently out of stock. Expected ship date later this month. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 11 ____________________________________ Time: 04:03:06 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Wingtip Nav question At 02:43 PM 3/8/2009, you wrote: > >In the Bob archer antenna install guide, it says that: > >"If two VOR receivers are being installed one antenna >should be installed in each wing tip and each antenna >connected to a receiver. This type of installation >would produce twice as much signal into each receiver >and this much signal increase would mean an increase >of about 25% increase in VOR range." I think he's trading off the options for numbers of antennas installed versus the number of radios. One antenna and a splitter drops energy to both radios by 50% which translates into approximately 30% drop in range for BOTH receivers. Each receiver having its own antenna recovers that drop in range. Having said that, know that under controlled flight using the airways, VORs used and prescribed changeover points along those airways insures a healthy signal to the radios . . . irrespective of relatively small losses in range alluded to by Bob's statement. >Can someone explain how this could be so? Currently >I have one in a wingtip and one on the tail, but due >to some new antenna needs I may be moving my tail >antenna. I don't understand how having one in each >wingtip would affect performance, considering they're >being connected to separate receivers, and each receiver >may be tuned to whole separate VOR's. > >I just don't get how it could be. Everything we do in life is ultimately grounded in the economics of energy management. Assuming all other things equal, two antennas will deliver 2x the energy to each radio versus one antenna and a splitter. In real life, antenna patterns around the aircraft will have more profound effects on range than numbers of antennas versus radios. Wing-tip mounted antennas cannot even come close to the overall performance of a clear-field antenna either for gain or patterns. In practice, they work just fine for the increasingly rare instances that VOR navigation is truly useful. Haven't turn a VOR receiver ON since I wrote this article for Sport Aviation Article almost 12 years ago: http://www.aeroelectric.com/articles/nailgun.pdf Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 12 ____________________________________ Time: 04:48:45 PM PST US Subject: RE: AeroElectric-List: Plasma III Wiring Again! From: Bruce, "Why would the power wire have to be shielded? ". Because it's there. It's designed to use the shield as the ground and the center wire as the power. Simply parts reduction. No reason it couldn't be extended with a standard wire. I wired mine via the positive side of the battery contactor (does not pass through it) to a nice power terminal connector strip from Stein. This allows an individual connection to each plasma box. I used two 5 amp Potter breaker switches on the panel and two in-line fuses rated at 30 amps right at the terminal strip (Bob's suggestion). This allows me to step down the wire size running to the 5 amp breakers. Unless the cable drops off the battery or the contactor falls off the firewall it should provide a solid connection. I am using Z-13/8 without a mag switch. Instead I use two of Stein's 1/4 indicator lights as shown by Lightspeed's diagram to indicate operational modes of each Plasma box. Further parts reduction. I intend to incorporate the optional output display from Lightspeed to show status of the system. I am also considering the addition of the potentiometer to rev it up. I'll drop some pictures next week. Glenn Do Not Archive ________________________________ From: owner-aeroelectric-list-server@matronics.com on behalf of Bruce Bell Sent: Fri 3/6/2009 3:47 PM Subject: AeroElectric-List: Plasma III Wiring Again! I have installed my Plasma III on the hot side of the fire wall. I have a shield around it with air from the rear engine baffle. Has anyone just ran a ground wire from pin 15 to ground and pin 8 direct to the Mag switch and then to the battery buss? The pull able breaker would be a 5A fuse. Why would the power wire have to be shielded? Thanks! Bruce Bell RV-4 N23BB 65 hours so far. You got to love it! DO NOT ARCHIVE! ________________________________ Message 13 ____________________________________ Time: 05:55:44 PM PST US From: "Richard E. Tasker" Subject: Re: AeroElectric-List: Wingtip Nav question They are VOR antennas for NAV radios. Last I knew the only VOR/NAV transmissions come from the ground... Dick Tasker Etienne Phillips wrote: > > > 2 antennae on one receiver and transmitter is not as easy as it seems. > > You need to match the distance between the antennae to the frequency, > and direction you expect to be receiving from... > > The length of cable inbetween the antennae is also important. Not for > the faint of heart... Best case is a signal strength that is about 80% > as good as 1 antenna from all directions. Worst case is that it's > twice as potent in one direction, and completely dead 90 degrees out. > > Unless you're trying to make a directional antennae array in which > case the best and worst cases swap around! > > For navigation, I like non-directional antennae :-) > > With this in mind, I have no idea what the install guide is referring > to. It may be that placing two non-connected VOR antennae right next > to each other causes them to interfere with one another, and by > mounting them as far apart as possible (on either wingtip) the > detrimental effects are halved. > > > On 08 Mar 2009, at 10:10 PM, Richard E. Tasker wrote: > >> >> >> What it is saying is to use two antennas (one per receiver), rather >> than one antenna with a splitter. >> >> Dick Tasker >> > > -- Please Note: No trees were destroyed in the sending of this message. We do concede, however, that a significant number of electrons may have been temporarily inconvenienced. -- ________________________________ Message 14 ____________________________________ Time: 07:58:04 PM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Looking for cover photo . . . Revision 12A update pages have been posted. Individuals with Revision 11 books are invited to update their documents with printouts of these .pdf files. http://aeroelectric.com/whatsnew.html I'm looking for a photo of a homebuilt for the front cover of the paper version of R12. It needs to be pretry high resolution especially if the picture is oriented landscape (long dimension horizontal) mode 'cause of how it needs to get cropped. This is sorta what I have in mind. The shot can be on the ground but background for the inserted text can't be too cluttered. Emacs! If anyone has an image they'd like to have considered I'd be pleased to see it. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 15 ____________________________________ Time: 08:22:19 PM PST US Subject: Re: AeroElectric-List: What is a ON-ON-ON switch used for? From: rparigor@SUFFOLK.LIB.NY.US Hi Bob Thx. for the reply. >>(What is a ON-ON-ON switch used for?)<< "ON-ON-ON is progressive transfer as described in detail in the chapter on switches.The 4-pole device can be wired to emulate a two-pole, three-position switch." The switch I have is 4 pole, double throw but is an on-on-on switch. Unlike the switch you depict in your book where although 2 positions are on-on, the second pole has the two on positions at the opposite end of throw compared to the first pole. I understand this switch can be wired to accomplish a tripple throw function. The switch I have has all four poles being exactly the same, top and middle toggle position has com and one side connected.I forget if it was the top or bottom row, dosen't matter all the poles are the same row. Then when you put toggle in the bottom position it connects com to the other side, again all poles are the same. My original question stands, what would a switch like this be used for with two positions doing exactly the same thing? Or perhaps the switch was built wrong and should have two of the four poles assembled where the two on positions are opposite each other? Thx. Ron Parigoris > ________________________________ Message 16 ____________________________________ Time: 10:08:42 PM PST US From: Etienne Phillips Subject: Re: AeroElectric-List: Wingtip Nav question You are correct - but when dealing with aerials and radiation patterns, it doesn't matter if you're talking about transmitting or receiving... As a side-note, if you have a DME instrument then you do transmit, but it's a completely different frequency range (and therefore I'm guessing has it's own antenna). I agree with Bob Nuckolls though, having a single antenna, mounted in a clear spot, is by far the best way of improving signal quality! Good luck with your installation... On 09 Mar 2009, at 2:54 AM, Richard E. Tasker wrote: > > > They are VOR antennas for NAV radios. Last I knew the only VOR/NAV > transmissions come from the ground... > > Dick Tasker > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.