AeroElectric-Archive.digest.vol-ji

February 05, 2010 - February 25, 2010



         life.
      
         The whole desulfator thing hasn't really been
         embraced by the battery industry. If an abused
         (deeply discharged) battery is capable of being
         recovered, then there are high-potential, charge-
         discharge routines that can be conducted on
         equipment that immediately measures and then
         confirms airworthiness . . . or says "trash it".
      
         The "break up the sulfate crystals" is problematic.
      
         I suspect the admonition for "non-aviation use"
         is a recognition that batteries in airplanes have
         unique duties for reducing risk. I suspect the
         folks who build such devices are simply worried
         about being dragged into a lawsuit for having
         sold one of their products into a tiny segment
         of the market place.
      
         For our purposes, it's far better to install
         and maintain a battery in a manner that gives
         us confidence for meeting design goals before
         gracefully retiring the battery at end of life.
         It just depends on how much you INTEND to depend
         on your battery's performance. If its a day-vfr-
         fair-weather machine, run it 'til it croaks.
      
         If you have a desire to maintain and be confident
         in  meeting design goals for battery-only endurance
         then your preventative maintenance plan is up to
         you and may include any tools you choose . . .
         including desulfators.  Paraphrasing a noteworthy
         modern philosopher, "Trust but verify".
      
         Bob . . .
      
      
________________________________________________________________________________
Subject: Re: Battery desulfators . . .
From: Ian <ixb(at)videotron.ca>
Date: Feb 05, 2010
A gentleman behind the counter at Aircraft Spruce Canada told me that he'd been using a trickle charger/de-sulphator for twelve years on the same battery. Based on that, I put my trust in his word and purchased one. Of course the only test of whether it's going to be doing it's job is a discharge test, rather than blind faith. It's currently maintaining the charge on the bench while I'm away for the winter. I have a feeling that a de-sulphator might be better used for maintenance than for attempting to recover a heavily crystallized battery. If any of this in any way disagrees with anything Guru Nuckolls says, then take his advice!! Ian Brown, Bromont, QC ________________________________________________________________________________
Subject: Re: Starter and contactor wiring
From: "user9253" <fran4sew(at)banyanol.com>
Date: Feb 05, 2010
> You got me. Never heard of the 12/24 volt jumper option. > If the starter will function when supplied with 24v > and the "S" terminal left open, then there's something > going on inside that I'm not aware of. Suggest you > follow instructions and leave the jumper installed. Could there be something like this inside of the starter? http://tinyurl.com/yallsk4 The manufacturer is pretty adamant about installing that jumper for 12 volts. It seems to me that wiring according to Van's diagram would work too, as long as 12 volts gets applied to that starter jumper-terminal while cranking. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=284974#284974 Attachments: http://forums.matronics.com//files/starter_202.jpg ________________________________________________________________________________
From: Jesse Jenks <jessejenks(at)hotmail.com>
Subject: RE: Starter engaged light, was Starter and contactor
wiring
Date: Feb 05, 2010
Interesting. Thanks. > From: aerobubba(at)earthlink.net > To: aeroelectric-list(at)matronics.com > Subject: AeroElectric-List: RE: Starter engaged light=2C was Starter and contactor wiring > Date: Fri=2C 5 Feb 2010 11:04:13 -0500 > link.net> > > Hi All- > > It's been a while since I went down my decision tree on this topic=2C and I > might not recall all the details perfectly=2C but it seems to me that the re > are a couple details of 'starter engaged' annunciation that might have be en > overlooked. First=2C it seems to me that the objective is to know whethe r > there is power on the starter or not=2C so tapping the fat wire between t he > solenoid and the motor would be in order. This would then annunciate th at > there was power to the starter motor itself. It also has the advantage o f > monitoring the spin down of the motor. Should the pinion hang and the > motor remain engaged after the solenoid opens=2C the back emf can keep th e > engaged light illuminated. It might be especially zippy if one were to u se > a bi-directional led for the indicator=2C such that one could perhaps hav e > amber indicate normal engagement and red to indicate run-on. Including a > zener diode could clip the spin-down indication during normal operation > while still allowing the run-on indication to function=2C should that bec ome > desirable. > > glen matejcek > aerobubba(at)earthlink.net > > > =========== =========== =========== =========== > > > _________________________________________________________________ Your E-mail and More On-the-Go. Get Windows Live Hotmail Free. ________________________________________________________________________________
Date: Feb 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: RE: Starter engaged light, was Starter and contactor
wiring At 10:04 AM 2/5/2010, you wrote: > > >Hi All- > >It's been a while since I went down my decision tree on this topic, and I >might not recall all the details perfectly, but it seems to me that there >are a couple details of 'starter engaged' annunciation that might have been >overlooked. First, it seems to me that the objective is to know whether >there is power on the starter or not, so tapping the fat wire between the >solenoid and the motor would be in order. This is how it's done on TC aircraft when the feature is installed. >This would then annunciate that >there was power to the starter motor itself. It also has the advantage of >monitoring the spin down of the motor. Should the pinion hang and the >motor remain engaged after the solenoid opens, the back emf can keep the >engaged light illuminated. Not true. Every starter has an over-run clutch that prevents back-driving of the motor armature via a stuck pinion gear. This is especially important for modern, highly-geared starters where the armature is already running 4-6000 rpm while cranking the engine a couple hundred RPM. Without an over-run clutch, an engine idling at say 1000 rpm would either over-speed the armature perhaps to destruction from thrown windings or commutator bars or stripped gear teeth in the gearbox. >It might be especially zippy if one were to use >a bi-directional led for the indicator, such that one could perhaps have >amber indicate normal engagement and red to indicate run-on. If a starter WERE in a back-drive mode, the polarity of voltage would not reverse . . . hence the starter-stuck light would not change colors . . . only get much brighter. > Including a zener diode could clip the spin-down indication during > normal operation while still allowing the run-on indication to > function, should that become desirable. An interesting hypothesis but not consistent with either the physics of motor operations or with the configuration of starter drive-trains. Bob . . . ________________________________________________________________________________
Date: Feb 05, 2010
Subject: Re: RE: Starter engaged light, was Starter and contactor
wiring
From: Bill Boyd <sportav8r(at)gmail.com>
Is this clutch protection found on SkyTec starters with a solenoid rather than a bendix for drive gear engagement? My LED starter warning light has stayed on many seconds after a successful start and made me wonder sometimes - I guess that's a separate issue of back-EMF energizing the solenoid somehow? I don't even have my wiring diagram in front of me at the moment...I should keep quiet and learn something ;-) Bill B On Fri, Feb 5, 2010 at 2:15 PM, Robert L. Nuckolls, III < nuckolls.bob(at)aeroelectric.com> wrote: > nuckolls.bob(at)aeroelectric.com> > > > At 10:04 AM 2/5/2010, you wrote: > >> aerobubba(at)earthlink.net> >> >> Hi All- >> >> It's been a while since I went down my decision tree on this topic, and I >> might not recall all the details perfectly, but it seems to me that there >> are a couple details of 'starter engaged' annunciation that might have >> been >> overlooked. First, it seems to me that the objective is to know whether >> there is power on the starter or not, so tapping the fat wire between the >> solenoid and the motor would be in order. >> > > This is how it's done on TC aircraft when the > feature is installed. > > > This would then annunciate that >> there was power to the starter motor itself. It also has the advantage of >> monitoring the spin down of the motor. Should the pinion hang and the >> motor remain engaged after the solenoid opens, the back emf can keep the >> engaged light illuminated. >> > > Not true. Every starter has an over-run clutch that > prevents back-driving of the motor armature via a > stuck pinion gear. This is especially important for > modern, highly-geared starters where the armature > is already running 4-6000 rpm while cranking the > engine a couple hundred RPM. > > Without an over-run clutch, an engine idling at > say 1000 rpm would either over-speed the armature > perhaps to destruction from thrown windings or > commutator bars or stripped gear teeth in the > gearbox. > > > It might be especially zippy if one were to use >> a bi-directional led for the indicator, such that one could perhaps have >> amber indicate normal engagement and red to indicate run-on. >> > > If a starter WERE in a back-drive mode, the polarity > of voltage would not reverse . . . hence the starter-stuck > light would not change colors . . . only get much brighter. > > > Including a zener diode could clip the spin-down indication during >> normal operation while still allowing the run-on indication to >> function, should that become desirable. >> > > An interesting hypothesis but not consistent with > either the physics of motor operations or with the > configuration of starter drive-trains. > > Bob . . . > > ________________________________________________________________________________
Date: Feb 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Starter and contactor wiring
At 11:23 AM 2/5/2010, you wrote: > > > > You got me. Never heard of the 12/24 volt jumper option. > > If the starter will function when supplied with 24v > > and the "S" terminal left open, then there's something > > going on inside that I'm not aware of. Suggest you > > follow instructions and leave the jumper installed. > >Could there be something like this inside of the starter? >http://tinyurl.com/yallsk4 >The manufacturer is pretty adamant about installing that jumper for 12 volts. Interesting! It's not clear to me how the pair of starter windings are managed . . . the PM starters I'm familiar with have windings only on an armature accessed through brushes. and commutators. To accomplish what's depicted would take a dual winding armature with two sets of brushes on each end of the winding stack. I've seen armatures like this . . . usually on dynamotors of the 1940-1960 era. Emacs! Here's an example of a 3-winding armature for a 24v motor, and two high voltage generators all on the same piece of moving machinery! I suppose one could do a 2-voltage starter with two 12 windings on one armature. It would have to be more complex than the drawing suggests. If you look at electron flow in the 24v mode, both coils run left to right. In the 12v mode, the left coil is left to right, the right coil is right to left . . . they would oppose each other unless the brush wiring to one of the windings is also reversed. Seems mighty complex just to get a "universal" starter. > It seems to me that wiring according to Van's diagram would work > too, as long as 12 volts gets applied to that starter > jumper-terminal while cranking. That's the way I see it too. Bob . . . ________________________________________________________________________________
Date: Feb 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Battery desulfators . . .
At 11:19 AM 2/5/2010, you wrote: A gentleman behind the counter at Aircraft Spruce Canada told me that he'd been using a trickle charger/de-sulphator for twelve years on the same battery. Based on that, I put my trust in his word and purchased one. What brand/model is it? I do not doubt his experience. I only question the analysis for cause/effect and performance. The fact that his battery might still get an engine started is not a good quantifier of stored energy. Cranking a typical piston engine from a battery takes perhaps 2% of the battery's total energy. Of course the only test of whether it's going to be doing it's job is a discharge test, rather than blind faith. You are correct in your suggestion that a deep-discharge cap-checks and perhaps load-testing are the true measure of battery capability. It's currently maintaining the charge on the bench while I'm away for the winter. I have a feeling that a de-sulphator might be better used for maintenance than for attempting to recover a heavily crystallized battery. If any of this in any way disagrees with anything Guru Nuckolls says, then take his advice!! It would be interesting to see what technology is offered in his 12+ years old device. If it's a true "trickle" charger, then it's an SLVA battery killer. The maintainers and smart chargers I have in my shop behave like . . . http://www.aeroelectric.com/Pictures/Curves/Battery_Tender_Recharge.pdf http://www.aeroelectric.com/Pictures/Curves/Battery_Minder_Recharge.pdf http://www.aeroelectric.com/Pictures/Curves/schumacher_2.jpg and http://www.aeroelectric.com/Pictures/Curves/schumacher_5.jpg Note in the fourth trace, there's a lot of "noise" on the data . . . it may well be that this charger has a feature designed to electrically "shake up" battery chemistry with some notion of preventing or reversing sulfation growth. I have some examples in my family of instrumentation batteries that still cap-check at 85+ percent of new after 6 years . . . so it seems that having a useful device after 12 years in similar storage may not be a stretch. If you check out the dozens of patents on devices that claim to rescue fair batteries in distress from the clutches of evil Dr. Sulfation, their approaches and explanations are all over the map. A search at http://freepatentsonline.com for . . . desulfator + battery + charger . . . yielded 38 hits. I've not read them in detail but keep in mind that for one to receive a patent, the process/hardware depicted must be UNIQUE. So in one resource alone we are made privy to 38 different approaches. Keep in mind also that the granting of a patent is no guarantee that the thing performs as advertised. I'm not suggesting that one or more such devices are not useful in some manner. I just don't KNOW. I DO suggest that MOST of what's offered is like putting magnets on your car's fuel lines to raise the octane of the gasoline as it passes by . . . If anyone has a real world solution to extending battery life by way of staving off or reversing sulfation, it's not yet apparent to me. I'm participating in the evaluation and commercialization of a remarkably innovative lead-acid aircraft battery that promises weight reduction and improved performance to boot. As soon as the business details of the program are finalized, I'll be able to talk about it more. However, The real bonus for me is an opportunity to know the chemistry gurus who are supporting the program. Battery sulfation and DE-SULFATION will be among numerous topics I'd like to discuss. Bob . . . ________________________________________________________________________________
From: Speedy11(at)aol.com
Date: Feb 05, 2010
Subject: Re: Starter and contactor wiring
Jesse, Bob has already expertly answered the question. For me, I was unsure whether it was the starter contactor or the starter solenoid that stuck causing the run-on starter. So, when I changed my wiring, I reasoned that 1) if I were pressing the starter button, I would know that 2) If the starter button itself stuck, I could see the starter light still on and remove power 3) If the contactor stuck, I could see the starter light on and remove power 4) The only way the starter solenoid could stick is if the contactor stuck - that is, removing power from a not-stuck contactor would, by definition, remove power from the starter. Thus, a stuck starter solenoid can only occur if it is still getting power from the contactor. When power is removed from the starter solenoid, then the gear drive will retract and disengage the starter. For me, the starter engaged light is a worthwhile addition. It tells me that power is or is not applied across the starter contactor. If it is not lit, then power is not being applied to the starter terminals (or the bulb is burned out) I considered running the starter light wire from the starter terminal, but reasoned that nothing is gained by doing so since power at the contactor I terminal indicates power is applied across the contactor. Regards, Stan Sutterfield I'm curious if the "starter engaged light" actually tells you anything more than that you are pressing the starter button with your thumb=2C which you should hopefully know already? In other words would the light actually inf orm you of a starter stuck on after the engine is running? I had been considering weather a light on the panel is worth wile or not. Thanks. Jesse PS I will be wiring like Vans=2C without the jumper. ________________________________________________________________________________
Date: Feb 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: S700-2-50 switch function
At 03:09 PM 2/5/2010, you wrote: > >Bob, > >My circuit requires a DPDT "on-on-(on)" switch action with a >make-before-break between center and momentary positions. Does the >S700-2-50 switch fulfill the make-before-break requirement? If it >doesn't, do you know of a source for such a switch? > >Thanks for all your help via the Aeroelectric list. I'm a loyal lurker. The switch mechanism is a "teter-toter" rocker that can only break the present connection long before the open contacts close. I'm not aware of any toggel switch that would operate any differently. Bob . . . ________________________________________________________________________________
Date: Feb 05, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Starter engaged light
At 01:53 PM 2/5/2010, you wrote: >Is this clutch protection found on SkyTec starters with a solenoid >rather than a bendix for drive gear engagement? I think so. The "Bendix" was sort of an automatic disengagement because over-running the starter motor would cause the pinion to retract back down its spiral engagement track. All direct engagement drives operated by solenoid are at risk of over-run damage if they do not have another form of clutch . . . usually a "sprag clutch" on the pinion shaft. > My LED starter warning light has stayed on many seconds after a > successful start and made me wonder sometimes - I guess that's a > separate issue of back-EMF energizing the solenoid somehow? What kind of starter? If it's a PM starter =AND you have the jumper installed between the starter solenoid "S" terminal and the Fat-Wire terminal, then yes . . . emf generated during spindown can keep the solenoid extended for an unnecessary length of time. This is why we recommend either a remote starter control relay (Z-22) =OR= direct control of the starter though a robust starter pushbutton. > I don't even have my wiring diagram in front of me at the > moment...I should keep quiet and learn something ;-) It would be helpful to know what kind of starter, and how it's wired. But the phenomenon you're observing may be a condition needing some attention. Bob . . . ________________________________________________________________________________
From: "glen matejcek" <aerobubba(at)earthlink.net>
Subject: RE:Starter engaged light, was Starter and contactor
wiring
Date: Feb 06, 2010
Hi Bob- > If a starter WERE in a back-drive mode, the polarity > of voltage would not reverse . . . hence the starter-stuck > light would not change colors . . . only get much brighter. > Duh- I need to stop pondering the digest pre-caffeine.... ;-) There was an airframe lost a while back due to a stuck contactor and the ensuing electrical fire, but that involved significantly different and more robust hardware. As ever, thanks for your help with the rectal-cranial inversion! glen matejcek aerobubba(at)earthlink.net ________________________________________________________________________________
Subject: Re: S700-2-50 switch function
From: "user9253" <fran4sew(at)banyanol.com>
Date: Feb 06, 2010
Jim, Perhaps additional components can be used to delay opening of the DP3T switch contacts while switching from one position to another. A large capacitor might help, depending on the current of the load. Or a relay can be used with its contacts in parallel with the DP3T contacts. See the attached sketch. http://tinyurl.com/ya5zkkv If you post a copy of your schematic, others can offer suggestions. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=285066#285066 Attachments: http://forums.matronics.com//files/switch_delay_opening_904.jpg ________________________________________________________________________________
From: MLWynn(at)aol.com
Date: Feb 06, 2010
Subject: Aux Alternator B Lead, Battery Buss
Hi all, I am building an all-electric RV 8 with a rear mounted battery. I was planning to use Z-12 architecture. On this drawing, both the B lead from the main alternator and the B lead from the auxiliary alternator terminate (with appropriate fusing) on the starter contactor hot side and hence to the aircraft side of the main battery contactor. In reviewing the setup recommended by Marc Ausman at Vertical Power (still scratching my head on whether or not to use the system), he recommends connecting the aux alternator B lead to the battery side of the battery contactor. _http://verticalpower.com/docs/VP_Config_2.pdf_ (http://verticalpower.com/docs/VP_Config_2.pdf) When I asked him why, he said the following: We wire the secondary alternator to the battery side of the contactor so that you can still use it if the battery contactor fails. Your normal operating mode is with the battery contactor closed and using the primary alternator. If the primary alternator fails, you can switch over to the secondary alternator. In this failure mode it really doesn't matter which side the secondary alternator is connected to. Another scenario is that you are flying along and the battery contactor fails. The VP-200 automatically detects this failure, load sheds, opens the battery contactor circuit just to be safe, and then switches over to the backup alternator. The VP-100 will flag the failure, then you have to manually switch to the backup alternator. In either case, the secondary alternator must be on the battery side to operate correctly (the SD-8 is an exception and will generate power without a battery in the loop, but there are too many scenarios to get into the nitty gritty). Power cannot flow from the alternator backwards through the electronic circuit breakers. So if the battery contactor failed open and both alts are on the bus side, you'd have no way to charge the battery or use it to regulate the bus voltage. Don't forget the secondary alternator b-lead is a hot wire (since it is connected to the battery) and needs a fuse in back near the battery. This is indicated on the wiring diagram. Also, the sec alt B-lead is usually a 10 or 12 gauge wire, so it is not that big or difficult to route. >From a practical wiring point of view, it would be a lot less wire to put both alternator B-leads to the starter contactor. On the other hand, running a 10 gauge wire to the battery side of the main contactor would then provide you with a way to wire a battery buss in the front of the airplane, as opposed to placing the battery buss next to the battery and running multiple wires to the front. I also have dual electronic ignition in this bird, so I am planning to place a second, small battery in the front that is dedicated to the second electronic ignition. I don't know if this changes how it should be set up. On an earlier post, Bob had said something about using a modified Z-14 with the endurance buss set up as the secondary shown in Z-14. Anyway, hope this hasn't been to confusing. This forum and the Aeroelectric book have been an invaluable source of education for a first-time builder. Regards, Michael Wynn RV 8 Finishing San Ramon, CA ________________________________________________________________________________
From: "John Burnaby" <jonlaury(at)impulse.net>
Subject: Re: RE: Starter engaged light, was Starter and contactor
wiring
Date: Feb 06, 2010
I am using a DPST momentary switch, with a lamp in it that is switched independently, wired to the coil of a starter contactor for my START button. I plan to wire the internal lamp to one side of the switch so that it goes on when the START button is depressed and also have a parallel wire going to the fat wire between the starter solenoid and the starter. So the lamp will light when I depress the START button and will go out when it is released...unless the starter solenoid is stuck closed and the fat wire between the starter solenoid and the starter is energized. See any glitches? ________________________________________________________________________________
Date: Feb 06, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: RE:Starter engaged light, was Starter and contactor
wiring >There was an airframe lost a while back due to a stuck contactor and the >ensuing electrical fire, but that involved significantly different and more >robust hardware. Do you have a source for more information on this event? >As ever, thanks for your help with the rectal-cranial inversion! No problem my friend . . . it's what we do . . . Bob . . . ________________________________________________________________________________
From: BobsV35B(at)aol.com
Date: Feb 06, 2010
Subject: Re: RE: Starter engaged light, was Starter and contactor
Good Afternoon Jon, Not sure if that is an open question to all or meant for 'Lectric Bob. Nevertheless, what advantage is it to you to know that the button has been pressed? Isn't what you really care about whether or not there is power within the fat wire going to the starter? Happy Skies, Old Bob Siegfried LL22 Stearman N3977A In a message dated 2/6/2010 12:35:16 P.M. Central Standard Time, jonlaury(at)impulse.net writes: I am using a DPST momentary switch, with a lamp in it that is switched independently, wired to the coil of a starter contactor for my START button. I plan to wire the internal lamp to one side of the switch so that it goes on when the START button is depressed and also have a parallel wire going to the fat wire between the starter solenoid and the starter. So the lamp will light when I depress the START button and will go out when it is released...unless the starter solenoid is stuck closed and the fat wire between the starter solenoid and the starter is energized. See any glitches? (http://www.matronics.com/Navigator?AeroElectric-List) (http://www.matronics.com/contribution) ________________________________________________________________________________
From: BobsV35B(at)aol.com
Date: Feb 06, 2010
Subject: Re: RE:Starter engaged light, was Starter and contactor
Good Afternoon 'Lectric Bob, I have a faint memory of a Cessna 210 having that sort of problem. I think that was the incident that prompted your old company to add starter engaged warning lights to their new production aircraft..Maybe around 1980 or so? Am I way off base here? Happy Skies, Old Bob In a message dated 2/6/2010 1:17:41 P.M. Central Standard Time, nuckolls.bob(at)aeroelectric.com writes: --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" >There was an airframe lost a while back due to a stuck contactor and the >ensuing electrical fire, but that involved significantly different and more >robust hardware. Do you have a source for more information on this event? >As ever, thanks for your help with the rectal-cranial inversion! No problem my friend . . . it's what we do . . . Bob . . . ________________________________________________________________________________
Date: Feb 06, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Starter engaged light
At 12:22 PM 2/6/2010, you wrote: >I am using a DPST momentary switch, with a lamp in it that is >switched independently, wired to the coil of a starter contactor for >my START button. I plan to wire the internal lamp to one side of the >switch so that it goes on when the START button is depressed and >also have a parallel wire going to the fat wire between the starter >solenoid and the starter. So the lamp will light when I depress the >START button and will go out when it is released...unless the >starter solenoid is stuck closed and the fat wire between the >starter solenoid and the starter is energized. > >See any glitches? The "starter engaged" light needs to get power from as far downstream as practical in the power/control wiring for the starter. The design goal for a starter engaged light is to annunciate a starter that is still powered AFTER the start button is released. The high risk cause for this is a stuck starter contactor. If you wire your starter engaged light to the start switch, then the only thing it can tell you is that the switch is stuck . . . if the contactor is stuck, it won't stay illuminated. If you're using an automotive starter contactor with an "I" terminal . . . http://www.aeroelectric.com/Pictures/Contactors/s702wire.jpg . . . then attaching the starter engaged light to that terminal (protected by a 3A fuse) monitors THAT contactor. If your contactor is not fitted with an "I" terminal, then attaching the light wire to the downstream side of the starter contactor is a good thing to do. Bob . . . ________________________________________________________________________________
Date: Feb 06, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Aux Alternator B Lead, Battery Buss
Ausman at Vertical Power (still scratching my head on whether or not to use the system), he recommends connecting the aux alternator B lead to the battery side of the battery contactor. http://verticalpower.com/docs/VP_Config_2.pdf When I asked him why, he said the following: We wire the secondary alternator to the battery side of the contactor so that you can still use it if the battery contactor fails. Your normal operating mode is with the battery contactor closed and using the primary alternator. If the primary alternator fails, you can switch over to the secondary alternator. In this failure mode it really doesn't matter which side the secondary alternator is connected to. Anyway, hope this hasn't been to confusing. This forum and the Aeroelectric book have been an invaluable source of education for a first-time builder. Keep in mind that when the installation manual for a system like Vertical Power =or= a Z-figure is published, the ARCHITECTURE is being crafted to meet certain design goals. The advice from Marc embraces the design philosophy for a two-layered electrical system as described in the notes for Z-13/8 and illustrated in the companion drawing. If your design goals are different and you are satisfied with the failure mode effects for a new configuration, then by all means . . . I'm not trying to champion anyone's architectures as being superior over any another . . . only the idea that there are REASONS why things are hooked up a particular way. Be sure you do the homework, take the exam and are satisfied with the grade before you shuffle things around. Bob . . . ________________________________________________________________________________
Date: Feb 06, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: starter engaged light
At 01:35 PM 2/6/2010, you wrote: >Good Afternoon 'Lectric Bob, > >I have a faint memory of a Cessna 210 having that sort of problem. I >think that was the incident that prompted your old company to add >starter engaged warning lights to their new production >aircraft..Maybe around 1980 or so? > >Am I way off base here? Not at all. Starter engaged lights were added to a number of Beechcraft airframes as reports came in about damage to starters and ring gears from stuck contactors. I was struck by the notion that such a failure started a chain of events that brought the airplane down. It would be interesting to read the reports on the incident if they can be retrieved. Some years ago at OSH, some airshow performer reported having "teased a starter contactor closed with the g-loads of the performance" causing it it to weld and ultimately do a lot of damage to the starter and ring gear. It's almost a sure bet that the contactor stuck during cranking and was simply overlooked as the performer was pre-occupied with the immediate task. G-loads just don't close a starter contactor . . . they MIGHT close an OPEN battery contactor . . . but who flies around with a battery contactor open? Bob . . . ________________________________________________________________________________
Subject: Re: Starter engaged light
From: "XeVision" <dblumel(at)XeVision.com>
Date: Feb 07, 2010
[quote="nuckolls.bob(at)aeroelect"]At 01:35 PM 2/6/2010, you wrote: > Good Afternoon 'Lectric Bob, > > I have a faint memory of a Cessna 210 having that sort of problem. I think that was the incident that prompted your old company to add starter engaged warning lights to their new production aircraft..Maybe around 1980 or so? > > Am I way off base here? Not at all. Starter engaged lights were added to a number of Beechcraft airframes as reports came in about damage to starters and ring gears from stuck contactors. I was struck by the notion that such a failure started a chain of events that brought the airplane down. It would be interesting to read the reports on the incident if they can be retrieved. Some years ago at OSH, some airshow performer reported having "teased a starter contactor closed with the g-loads of the performance" causing it it to weld and ultimately do a lot of damage to the starter and ring gear. It's almost a sure bet that the contactor stuck during cranking and was simply overlooked as the performer was pre-occupied with the immediate task. G-loads just don't close a starter contactor . . . they MIGHT close an OPEN battery contactor . . . but who flies around with a battery contactor open? Bob . . . > [b] That is one reason why all of my solenoids are mounted sideways. -------- 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=285218#285218 ________________________________________________________________________________
From: "glen matejcek" <aerobubba(at)earthlink.net>
Subject: RE: Starter engaged light, was Starter and contactor
Date: Feb 07, 2010
I'll see what I can scrounge up. I don't think an accident report was generated, but I know a fellow who was involved and will see what details I can get. >There was an airframe lost a while back due to a stuck contactor and the >ensuing electrical fire, but that involved significantly different and more >robust hardware. Do you have a source for more information on this event? glen matejcek aerobubba(at)earthlink.net ________________________________________________________________________________
From: "glen matejcek" <aerobubba(at)earthlink.net>
Subject: RE: was Starter engaged light, was Starter and contactor
wiring, now lost airframe
Date: Feb 07, 2010
Hi Bob- I was able to find this: http://www.ntsb.gov/ntsb/GenPDF.asp?id=FTW90DRA10&rpt=fi Some of the physical description of the airframe may be a bit misleading, but teh fundamental process seems to be accurate. glen matejcek aerobubba(at)earthlink.net ________________________________________________________________________________
Subject: RS-232
From: "PaulR" <prose(at)panhandle.rr.com>
Date: Feb 07, 2010
I'm wiring up my panel and was getting ready to hook the Dynon D-100 serial output to the GTX-327. Reading the wiring diagram for the Garmin, it says to hook the TX wire from the Dynon to a certain pin.(I forgot which number) and that the RS-232 GND to either of two chassis grounds on the Garmin. I take that to mean that the RS-232 gnd should be at the same potential as the rest of the 12V grounds and could be connected to the "forrest of tabs" where the balance of the grounds are hooked. If that's true, then couldn't all the RS-232 gnds be connected there, along with their respective shields? Am I thinking this through correctly? Thanks -------- Paul Rose N417PR (res) RV-9A Read this topic online here: http://forums.matronics.com/viewtopic.php?p=285272#285272 ________________________________________________________________________________
Date: Feb 07, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Starter engaged light
> It's almost a sure bet that the contactor stuck during > cranking and was simply overlooked as the performer > was pre-occupied with the immediate task. G-loads > just don't close a starter contactor . . . they MIGHT > close an OPEN battery contactor . . . but who flies > around with a battery contactor open? > > Bob . . . > > > [b] > > >That is one reason why all of my solenoids are mounted sideways. Why? Under what conditions of system operation and maneuvers in flight would you expect an increased risk of unintended behaviors? Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ ________________________________________________________________________________
Date: Feb 07, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: RS-232
At 05:40 PM 2/7/2010, you wrote: > >I'm wiring up my panel and was getting ready to hook the Dynon D-100 >serial output to the GTX-327. Reading the wiring diagram for the >Garmin, it says to hook the TX wire from the Dynon to a certain >pin.(I forgot which number) and that the RS-232 GND to either of two >chassis grounds on the Garmin. I take that to mean that the RS-232 >gnd should be at the same potential as the rest of the 12V grounds >and could be connected to the "forrest of tabs" where the balance of >the grounds are hooked. > >If that's true, then couldn't all the RS-232 gnds be connected >there, along with their respective shields? SIGNAL grounds are different and sometimes separate of POWER grounds. The forest-of-tabs is for the grounding of electrical accessories. When it comes to wiring components of a radio, navigation or other electronics, follow the instructions. SIGNAL grounds are like the grounds for microphones, headsets, etc and are given specific treatment. See the documentation on the DIY audio isolation amplifier on my website for examples. Bob . . . ________________________________________________________________________________
Date: Feb 07, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Stuck starter contactor . . .
At 02:00 PM 2/7/2010, you wrote: > > >Hi Bob- > >I was able to find this: > >http://www.ntsb.gov/ntsb/GenPDF.asp?id=FTW90DRA10&rpt=fi > >Some of the physical description of the airframe may be a bit misleading, >but teh fundamental process seems to be accurate. Hmmmm . . . interesting. I'm wondering how the operator 'knew' that the starter contactor had stuck when the FAA inspection could not identify a source of the fire. If somebody 'knew' the starter contactor was stuck or still energized, I'm mystified as to why the aircraft ever left the parking place. A starter feeder should have been protected from destructive overload by some means . . . c/b, current limiter, etc. Since the fire apparently didn't originate under the cowl (from a self-destructing starter) then components that failed to the point of starting a fire had to be things like unprotected wires, failed insulation, failed contactor, etc. It's quite possible that the starter contactor on this airplane looked something like this when new . . . http://www.aeroelectric.com/Pictures/Contactors/6041_Contactor.jpg and may well have degenerated to something like this when failed . . . http://aeroelectric.com/Pictures/Failures/6041_Contactor_Failure.jpg A contactor that is "stuck" is generally turned on 'hard' and is not generating a lot of heat. On the other hand, this style of contactor (mounted in the wheel-well j-box?) needs to be inspected (note removable cover) periodically for degraded contacts or signs of heating off the moving contact carrier. When these contactors experience a high- resistance overheat, they can fail rather spectacularly. The failed contactor I showed came out of a j-box that routes power to a 130A a/c compressor motor. These contactors have a relatively high failure rate . . . but being inside a metal enclosure keeps things from getting out of hand. It's also interesting that re-ignition was attributed to "hot" metal. Things that ignite from hot metal are liquids with easily ignited vapors . . . it doesn't sound like this fire went on long enough and with sufficient fuel to heat aluminum structure or steel landing gear parts to the point where they become re-ignition hazards. On the other hand, things that are combustible within the j-box may have been supporting some glowing coals and been shielded from the extinguisher. . . or it may be that power was still present in the j-box. In any case, it seems unlikely that the real chain of events for this unfortunate demise of an otherwise perfectly good airplane are known. Given its age, it was certainly subject to the effects of time on electrical system materials that were the best-we-knew- how-to-do in 1940. One needs to spend an extra effort to track these materials for continued airworthiness. Calling this one a "stuck starter contactor" incident is a WAG. Bob . . . ________________________________________________________________________________
Subject: Question on switch wiring
Date: Feb 08, 2010
From: <longg(at)pjm.com>
I bought a SPST 12 volt lighted switch from digi-key which I would like to use as a fuel pump indicator switch. SWITCH TOGGLE ILLUM SPST 20A GRN SCHED B: 853650 ECCN: EAR99 LEAD: LEAD ALL ROHS: ROHS NONC CH652-ND Assumptions: My fuel pump runs via a relay switch (20 amp B & C S704-1 job). Question: The switch is provided with a third 1/4" tab on the top (on position) of the switch. Normal use is to add a jumper from the on position to the top tab to illuminate light when turned on. The switch works great when used with standard power/ground connection, e.g. landing light. When I use it in conjunction with the relay switch, the light comes on when the switch is in the off position. Ideas appreciated. Glenn ________________________________________________________________________________
From: "John Burnaby" <jonlaury(at)impulse.net>
Subject: Re: RE: Starter engaged light, was Starter and contactor
Date: Feb 08, 2010
Hello Old Bob, Thanks for giving this some thought. The purpose of the lamp going on when I depress the starter is as a test of the lamp. John ________________________________________________________________________________
Date: Feb 08, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Question on switch wiring
At 12:33 PM 2/8/2010, you wrote: >I bought a SPST 12 volt lighted switch from digi-key which I would >like to use as a fuel pump indicator switch. > >SWITCH TOGGLE ILLUM SPST 20A GRN >SCHED B: 853650 >ECCN: EAR99 >LEAD: LEAD ALL >ROHS: >ROHS NONC >CH652-ND > >Assumptions: My fuel pump runs via a relay switch (20 amp B & C S704-1 job). > > >Question: The switch is provided with a third 1/4" tab on the top >(on position) of the switch. Normal use is to add a jumper from the >on position to the top tab to illuminate light when turned on. > >The switch works great when used with standard power/ground >connection, e.g. landing light. When I use it in conjunction with >the relay switch, the light comes on when the switch is in the off position. First, why the relay? The switch is rated for 20A . . . probably enough to control the pump directly. The third terminal is for grounding the internal LED/Resistor combination so that the lamp lights when the switch is closed. For this switch to be "relay augmented" you'll have to wire the pump as shown here: Emacs! . . . and this is not a very elegant approach. Unfortunately the switch you have (like most of it's cousins) doesn't bring BOTH lamp leads out for independent excitation of the lamp. One end of the lamp is tied to the "power output" terminal in the assumption that one ALWAYS uses the switch barefoot to control power in the +supply lead. Bob . . . ________________________________________________________________________________
From: BobsV35B(at)aol.com
Date: Feb 08, 2010
Subject: Re: RE: Starter engaged light, was Starter and contactor
Good Afternoon John, That sounds good, but if the starter works, won't that give you a check of the lamp? The way Beech handled the test function was to present a current from a dedicated lamp test switch to the starter warning lamp. To keep the lamp current from trying to drive the starter, they added a diode that only allows current from the starter to the light and blocks the flow from the lamp to the starter. That way we can check the light without closing the starter relay I did the same thing when I wired my warning lights. Since my factory warning lights were wired a bit differently, I used a double pole, single throw, switch to isolate the starter warning light circuit from the other warning circuits. Works great! Happy Skies, Old Bob In a message dated 2/8/2010 2:11:39 P.M. Central Standard Time, jonlaury(at)impulse.net writes: Hello Old Bob, Thanks for giving this some thought. The purpose of the lamp going on when I depress the starter is as a test of the lamp. John ________________________________________________________________________________
Subject: Question on switch wiring
Date: Feb 08, 2010
From: <longg(at)pjm.com>
Thanks Bob, Yes, the switch is overkill (or in reality, perhaps the relay is), but the switch matches the others if underutilized. I did not look hard and long enough for a 1 amp or lower with the same size/style. The pump shipped with 12 ga. wire leads and I really did not want to run a 12 ga. wire to the switch, thus the relay. The FP is rated for 7-10 amps. The FP is on the checklist but it's one of the easy to forget items that sometimes gets left on or off. Therefore an pilot light of some kind is a nice feature. Glenn E. Long From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Monday, February 08, 2010 3:02 PM Subject: Re: AeroElectric-List: Question on switch wiring At 12:33 PM 2/8/2010, you wrote: I bought a SPST 12 volt lighted switch from digi-key which I would like to use as a fuel pump indicator switch. SWITCH TOGGLE ILLUM SPST 20A GRN SCHED B: 853650 ECCN: EAR99 LEAD: LEAD ALL ROHS: ROHS NONC CH652-ND Assumptions: My fuel pump runs via a relay switch (20 amp B & C S704-1 job). Question: The switch is provided with a third 1/4" tab on the top (on position) of the switch. Normal use is to add a jumper from the on position to the top tab to illuminate light when turned on. The switch works great when used with standard power/ground connection, e.g. landing light. When I use it in conjunction with the relay switch, the light comes on when the switch is in the off position. First, why the relay? The switch is rated for 20A . . . probably enough to control the pump directly. The third terminal is for grounding the internal LED/Resistor combination so that the lamp lights when the switch is closed. For this switch to be "relay augmented" you'll have to wire the pump as shown here: . . . and this is not a very elegant approach. Unfortunately the switch you have (like most of it's cousins) doesn't bring BOTH lamp leads out for independent excitation of the lamp. One end of the lamp is tied to the "power output" terminal in the assumption that one ALWAYS uses the switch barefoot to control power in the +supply lead. Bob . . . ________________________________________________________________________________
Date: Feb 08, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Question on switch wiring
At 04:44 PM 2/8/2010, you wrote: >Thanks Bob, > >Yes, the switch is overkill (or in reality, perhaps the relay is), >but the switch matches the others if underutilized. I did not look >hard and long enough for a 1 amp or lower with the same size/style. >The pump shipped with 12 ga. wire leads and I really did not want to >run a 12 ga. wire to the switch, thus the relay. The FP is rated for 7-10 amps. Do you have real world current values for what the pump needs in normal operations? Is this a flight pump or an aux/boost pump that is seldom used/needed? 7A (100 watts) is a LOT of power for the pumping of fuel. While your pump may be capable of drawing that much current at rated maximum volume and pressure, I've found that most real-world installations are much less demanding. I think it likely that you can simply wire the pump system with 16 awg wires through the un-aided switch protected by a 10A fuse/breaker. But you need to get some real numbers from somebody who's flying the system or the folks who engineered the system and have numbers. Alternatively, wire it all with 14AWG, 15A breaker and leave the relay out. MUCH simpler and more reliable. The built in lamp can be used as defined in original design goals. Bob. . . ________________________________________________________________________________
Date: Feb 08, 2010
From: "Brooks Wolfe" <slipstream(at)wavecable.com>
Subject: GNS 430 no comm
I'm just wrapping up my 430 installation, and was hoping to hear somethin g (anything) through my headphones.. Nada. I have a used GNS 430 from Wentworth installed. New Sigtronics intercom (at least *this* works). The Garmin is plugged into the intercom with the 50 0 Ohm Audio Hi output. The 500 Ohm Audio Lo is grounded. The Garmin insta ll manual shows a paired "Audio 1" Hi and Low on P4001, but I can't find any other use for it mentioned anywhere, so it's not connected. Pressing the squelch button also makes no noise, as I would have expected =2E One issue that has me concerned is an incident in my hangar a few weeks a go -- A particularly long and bizarre chain of events led to the GNS430 dropping from table to concrete floor. Not far, but enough to give the c ase a tiny bit of wrinkle at the back end. While the unit seems to power up just fine, I can't help but wonder if there might have been some physical damage, causing this inability to get audio. Brooks ________________________________________________________________________________
Date: Feb 08, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Starter engaged light
At 02:01 PM 2/8/2010, you wrote: >Hello Old Bob, > >Thanks for giving this some thought. > >The purpose of the lamp going on when I depress the starter is as a >test of the lamp. The rule of thumb for lights that routinely illuminate during the process of getting ready for flight don't need press-to-test features. For example, the low volts warning light should be flashing at you before the engine starts and go out when the alternator comes on line. The starter engaged light should be illuminated while you're cranking and go out when you release the button. The criteria for "pre-flight-detectable" are satisfied. Bob . . . ________________________________________________________________________________
Date: Feb 09, 2010
Subject: Re: GNS 430 no comm
From: Ed Gilroy <egilroy(at)gmail.com>
Call Garmin. When ours went out like this (installed several years ago) we sent it to them and they inspected it repaired it. I think it was like $100. On Mon, Feb 8, 2010 at 11:21 PM, Brooks Wolfe wrote: > > I'm just wrapping up my 430 installation, and was hoping to hear something > (anything) through my headphones.. Nada. > > I have a used GNS 430 from Wentworth installed. New Sigtronics intercom > (at least *this* works). The Garmin is plugged into the intercom with the > 500 Ohm Audio Hi output. The 500 Ohm Audio Lo is grounded. The Garmin > install manual shows a paired "Audio 1" Hi and Low on P4001, but I can't > find any other use for it mentioned anywhere, so it's not connected. > > Pressing the squelch button also makes no noise, as I would have expected. > > One issue that has me concerned is an incident in my hangar a few weeks ago > -- A particularly long and bizarre chain of events led to the GNS430 > dropping from table to concrete floor. Not far, but enough to give the case > a tiny bit of wrinkle at the back end. While the unit seems to power up > just fine, I can't help but wonder if there might have been some physical > damage, causing this inability to get audio. > > Brooks > > * > > * > > ________________________________________________________________________________
From: John Grosse <grosseair(at)comcast.net>
Subject: Re: GNS 430 no comm
Date: Feb 09, 2010
It's $800 now. Sent from my iPod On Feb 9, 2010, at 5:54 AM, Ed Gilroy wrote: > Call Garmin. When ours went out like this (installed several years > ago) we sent it to them and they inspected it repaired it. I think > it was like $100. > > > On Mon, Feb 8, 2010 at 11:21 PM, Brooks Wolfe > wrote: > > I'm just wrapping up my 430 installation, and was hoping to hear > something (anything) through my headphones.. Nada. > > I have a used GNS 430 from Wentworth installed. New Sigtronics > intercom (at least *this* works). The Garmin is plugged into the > intercom with the 500 Ohm Audio Hi output. The 500 Ohm Audio Lo is > grounded. The Garmin install manual shows a paired "Audio 1" Hi and > Low on P4001, but I can't find any other use for it mentioned > anywhere, so it's not connected. > > Pressing the squelch button also makes no noise, as I would have > expected. > > One issue that has me concerned is an incident in my hangar a few > weeks ago -- A particularly long and bizarre chain of events led to > the GNS430 dropping from table to concrete floor. Not far, but > enough to give the case a tiny bit of wrinkle at the back end. > While the unit seems to power up just fine, I can't help but wonder > if there might have been some physical damage, causing this > inability to get audio. > > Brooks > > > ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List > tp://forums.matronics.com > _blank">http://www.matronics.com/contribution > > ________________________________________________________________________________
Subject: Question on switch wiring
Date: Feb 09, 2010
From: <longg(at)pjm.com>
Excellent, I'm all for simplification. Before I touch it I will get the real numbers. Thanks Bob. -----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: Monday, February 08, 2010 6:30 PM Subject: RE: AeroElectric-List: Question on switch wiring At 04:44 PM 2/8/2010, you wrote: >Thanks Bob, > >Yes, the switch is overkill (or in reality, perhaps the relay is), >but the switch matches the others if underutilized. I did not look >hard and long enough for a 1 amp or lower with the same size/style. >The pump shipped with 12 ga. wire leads and I really did not want to >run a 12 ga. wire to the switch, thus the relay. The FP is rated for 7-10 amps. Do you have real world current values for what the pump needs in normal operations? Is this a flight pump or an aux/boost pump that is seldom used/needed? 7A (100 watts) is a LOT of power for the pumping of fuel. While your pump may be capable of drawing that much current at rated maximum volume and pressure, I've found that most real-world installations are much less demanding. I think it likely that you can simply wire the pump system with 16 awg wires through the un-aided switch protected by a 10A fuse/breaker. But you need to get some real numbers from somebody who's flying the system or the folks who engineered the system and have numbers. Alternatively, wire it all with 14AWG, 15A breaker and leave the relay out. MUCH simpler and more reliable. The built in lamp can be used as defined in original design goals. Bob. . . ________________________________________________________________________________
From: Kevin Boddicker <trumanst(at)neitel.net>
Subject: Re: Starter engaged light
Date: Feb 09, 2010
Bob, I was concerned when I read this post, as my OV/LV Sensor is just the opposite. The documentation that was provided from B&C states that "A flashing light indicates a bus voltage greater than 15.5 volts DC, ; Steady light indicates bus voltage below 12.5 volts DC." That is how mine operates. Just trying to keep the confusion to a minimum. Thanks for all you do. Kevin Boddicker Tri Q 200 N7868B 153 hours, and waiting for some flying weather!!! Luana, IA. On Feb 8, 2010, at 5:33 PM, Robert L. Nuckolls, III wrote: > At 02:01 PM 2/8/2010, you wrote: >> Hello Old Bob, >> >> Thanks for giving this some thought. >> >> The purpose of the lamp going on when I depress the starter is as >> a test of the lamp. > > The rule of thumb for lights that routinely illuminate > during the process of getting ready for flight don't need > press-to-test features. For example, the low volts warning > light should be flashing at you before the engine starts > and go out when the alternator comes on line. The starter > engaged light should be illuminated while you're cranking > and go out when you release the button. The criteria for > "pre-flight-detectable" are satisfied. > > Bob . . . > > ________________________________________________________________________________
From: "glen matejcek" <aerobubba(at)earthlink.net>
Subject: RE: Stuck starter contactor
Date: Feb 09, 2010
HI Bob- > Hmmmm . . . interesting. I'm wondering how the operator 'knew' > that the starter contactor had stuck when the FAA inspection > could not identify a source of the fire. As I recall, about the first indication they had was brown smoke coming from the nacelle. I believe that's why they felt it electrical in origin. The generator, starter, and feathering pump are the only fat-wired items out there. The generators are off line anywhere near idle, and the feathering pumps had yet to be checked, as I understand it. The starter was the only of the relevant systems used by that point in time. The volt meter might have been informative, but the ammeters would have shown zero under these circumstances. Also, I don't think there was much relevant airframe left for the feds to look at by the time it was all over. I don't know how the plane was loaded, but the right wing could have had as much as 500 gals of gas and 50 gals of oil, all of it directly accessible from or actually in the wheel well. (This airplane did not have starter engaged lights, but as a result of this event, ours does). > > If somebody 'knew' the starter contactor was stuck or > still energized, I'm mystified as to why the aircraft > ever left the parking place. They didn't know the contactor failed until the event was well under way. > > A starter feeder should have been protected from destructive > overload by some means . . . c/b, current limiter, etc. The only circuit protection for any of the fat wires on this plane is the reverse current relay. In fact, the external power socket in the aft fuselage is hard wired directly to the buss. The crew has no direct control over the application of ground power to the buss, and anytime the buss is hot, so is the ground power receptacle as well as the 25 or so feet of connecting fat wire. Seems odd, especially for a combat aircraft. Nothing like an arcing fat wire in the bomb bay... > Since the fire apparently didn't originate under the cowl > (from a self-destructing starter) then components that failed > to the point of starting a fire had to be things like > unprotected wires, failed insulation, failed contactor, etc. That was their reasoning as well. An error in the report is the location of the J-box. It is actually under the nacelle fairing atop the wing skin. This j-box contains both the feathering pump contactor and the starter contactor. Just aft of the J-box under the same fairing is the fuel transfer pump and associated hard and soft plumbing. > > It's quite possible that the starter contactor on this > airplane looked something like this when new . . . > > http://www.aeroelectric.com/Pictures/Contactors/6041_Contactor.jpg > > and may well have degenerated to something like this > when failed . . . > > http://aeroelectric.com/Pictures/Failures/6041_Contactor_Failure.jpg > > A contactor that is "stuck" is generally turned on 'hard' > and is not generating a lot of heat. On the other hand, > this style of contactor (mounted in the wheel-well j-box?) > needs to be inspected (note removable cover) periodically > for degraded contacts or signs of heating off the moving > contact carrier. I don't know what type of maintenance regimen that aircraft was on, but ours is on an AAIP and that inspection is a regularly scheduled item. One other thing about this particular contactor is that material sloughed off the contacts can bind the mechanism. >When these contactors experience a high- > resistance overheat, they can fail rather spectacularly. That was also what the operator thought. Given what they experienced, they surmised that the contactor did a kind of 'china syndrome' and burned down through the wing skin into the wheel well and compromised the fuel selector valve or related plumbing. > > The failed contactor I showed came out of a j-box that > routes power to a 130A a/c compressor motor. These contactors > have a relatively high failure rate . . . but being > inside a metal enclosure keeps things from getting > out of hand. > > It's also interesting that re-ignition was attributed to > "hot" metal. Things that ignite from hot metal are liquids > with easily ignited vapors . . . it doesn't sound like this > fire went on long enough and with sufficient fuel to heat > aluminum structure or steel landing gear parts to the point > where they become re-ignition hazards. On the other hand, > things that are combustible within the j-box may have > been supporting some glowing coals and been shielded from > the extinguisher. . . or it may be that power was still > present in the j-box. Most of the fuel lines are cloth / rubber hoses, and the original wiring also had cloth insulation. The fuel selector valve is shielded from below to protect it from materials thrown by the tire. This shielding could well interfere with extinguishing. Of course, the wheel well is right behind a radial engine, and contains several hinged and telescoping hydraulic lines, and I have no knowledge of how clean it was or wasn't. > > In any case, it seems unlikely that the real chain of > events for this unfortunate demise of an otherwise > perfectly good airplane are known. Given its age, > it was certainly subject to the effects of time on > electrical system materials that were the best-we-knew- > how-to-do in 1940. One needs to spend an extra effort > to track these materials for continued airworthiness. Amen, brother- > > Calling this one a "stuck starter contactor" incident > is a WAG. The comment about 'the right generator would not accept a load' makes me wonder about the reverse current relay, which actually IS in the wheel well. I'm sure if the RCR stuck closed the battery would get discharged fairly quickly, but I wonder if the current would be great enough to do damage as long as the engine was at least at idle? Hmmm... > > Bob . . . > glen matejcek aerobubba(at)earthlink.net ________________________________________________________________________________
From: MLWynn(at)aol.com
Date: Feb 09, 2010
Subject: Re: Aux Alternator B Lead, Battery Buss
Thanks for this Bob. I am trying to do my homework. I am not an electrical engineer and have profited a great deal from what is written here. I guess I don't clearly understand what happens to some of the components in a fail mode. So the first question is, where does the B-lead from the aux alt go? If it is connected with the main alt B-lead to the starter side of the main contactor, then the failure mode goes like this: 1. Main alt fails, turn off it's field and turn on the aux alt. Shed load to 80% of the aux alternator rating (80%X20 amp= 16 amp max). 2. If the main contactor fails open, will the main alternator function okay? 3. If the battery shorts ( a rare occurrence, to be sure) then open the main contactor. Does the main alt work okay? 4. Main alt fails followed by a failure of the battery contactor. Are we still okay? If the aux alt is connected to the battery side of the battery contactor: 1. Main alt fails, turn off it's field and turn on the aux alt. Shed load to 80% of the aux alternator rating (80%X20 amp= 16 amp max). Not a problem 2. If the main contactor fails open, will the main alt still be okay or do I switch to the aux alternator because it has a direct battery connection? 3. If the battery shorts, that should burn out the fuse between the aux alternator B-lead if that alternator is being used. Is the main still functional? The question I am getting to, I think, is how does the system perform if the battery is out of the circuit either because the main contactor fails or we have to open it to free us from a failed battery. Back to my original question. Where should the aux alternator B-lead go and why? Thanks Michael Wynn RV 8 Finishing In a message dated 2/6/2010 12:19:19 P.M. Pacific Standard Time, nuckolls.bob(at)aeroelectric.com writes: --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" Ausman at Vertical Power (still scratching my head on whether or not to use the system), he recommends connecting the aux alternator B lead to the battery side of the battery contactor. http://verticalpower.com/docs/VP_Config_2.pdf When I asked him why, he said the following: We wire the secondary alternator to the battery side of the contactor so that you can still use it if the battery contactor fails. Your normal operating mode is with the battery contactor closed and using the primary alternator. If the primary alternator fails, you can switch over to the secondary alternator. In this failure mode it really doesn't matter which side the secondary alternator is connected to. Anyway, hope this hasn't been to confusing. This forum and the Aeroelectric book have been an invaluable source of education for a first-time builder. Keep in mind that when the installation manual for a system like Vertical Power =or= a Z-figure is published, the ARCHITECTURE is being crafted to meet certain design goals. The advice from Marc embraces the design philosophy for a two-layered electrical system as described in the notes for Z-13/8 and illustrated in the companion drawing. If your design goals are different and you are satisfied with the failure mode effects for a new configuration, then by all means . . . I'm not trying to champion anyone's architectures as being superior over any another . . . only the idea that there are REASONS why things are hooked up a particular way. Be sure you do the homework, take the exam and are satisfied with the grade before you shuffle things around. Bob . . . ________________________________________________________________________________
From: "Bob Leffler" <rv(at)thelefflers.com>
Subject: Aux Alternator B Lead, Battery Buss
Date: Feb 09, 2010
Michael, I'm currently planning a VP-200 implementation at the moment. I'm not an expert, but I'll share my opinion. See my comments inline... bob From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of MLWynn(at)aol.com Sent: Tuesday, February 09, 2010 6:17 PM Subject: Re: AeroElectric-List: Aux Alternator B Lead, Battery Buss Thanks for this Bob. I am trying to do my homework. I am not an electrical engineer and have profited a great deal from what is written here. I guess I don't clearly understand what happens to some of the components in a fail mode. So the first question is, where does the B-lead from the aux alt go? Config 2 has the alt alternator connected between the battery and the battery contactor. If it is connected with the main alt B-lead to the starter side of the main contactor, then the failure mode goes like this: 1. Main alt fails, turn off it's field and turn on the aux alt. Shed load to 80% of the aux alternator rating (80%X20 amp= 16 amp max). ok 2. If the main contactor fails open, will the main alternator function okay? It should, but your battery won't charge 3. If the battery shorts ( a rare occurrence, to be sure) then open the main contactor. Does the main alt work okay? It should work just fine. 4. Main alt fails followed by a failure of the battery contactor. Are we still okay? Yes, assuming that the alt alternator is attached between the battery and starter contactors. If the aux alt is connected to the battery side of the battery contactor: 1. Main alt fails, turn off it's field and turn on the aux alt. Shed load to 80% of the aux alternator rating (80%X20 amp= 16 amp max). Not a problem 2. If the main contactor fails open, will the main alt still be okay or do I switch to the aux alternator because it has a direct battery connection? Yes it's ok, and yes the alt alternator can charge the battery if needed and drive an e-bus 3. If the battery shorts, that should burn out the fuse between the aux alternator B-lead if that alternator is being used. Is the main still functional? Should be as long as the main alternator hasn't failed. The question I am getting to, I think, is how does the system perform if the battery is out of the circuit either because the main contactor fails or we have to open it to free us from a failed battery. Back to my original question. Where should the aux alternator B-lead go and why? I'm actually working on a slightly different variant, but am asking similar questions. I'm also adding a second battery to config 2 that will drive the endurance buss and can be brought online in parallel if needed for those really cold morning starts. The placement of the back up alternative doesn't seem to have a significant impact as long as you ensure that only one alternator is on at a time. If it's behind the battery contactor then you added another failure point in my mind. I'm planning on giving Marc a call in the morning to discuss. bob Thanks Michael Wynn RV 8 Finishing In a message dated 2/6/2010 12:19:19 P.M. Pacific Standard Time, nuckolls.bob(at)aeroelectric.com writes: Ausman at Vertical Power (still scratching my head on whether or not to use the system), he recommends connecting the aux alternator B lead to the battery side of the battery contactor. http://verticalpower.com/docs/VP_Config_2.pdf When I asked him why, he said the following: We wire the secondary alternator to the battery side of the contactor so that you can still use it if the battery contactor fails. Your normal operating mode is with the battery contactor closed and using the primary alternator. If the primary alternator fails, you can switch over to the secondary alternator. In this failure mode it really doesn't matter which side the secondary alternator is connected to. Anyway, hope this hasn't been to confusing. This forum and the Aeroelectric book have been an invaluable source of education for a first-time builder. Keep in mind that when the installation manual for a system like Vertical Power =or= a Z-figure is published, the ARCHITECTURE is being crafted to meet certain design goals. The advice from Marc embraces the design philosophy for a two-layered electrical system as described in the notes for Z-13/8 and illustrated in the companion drawing. If your design goals are different and you are satisfied with the failure mode effects for a new configuration, then by all means . . . I'm not trying to champion anyone's architectures as being superior over any another . . . only the idea that there are REASONS why things are hooked up a particular way. Be sure you do the homework, take the exam and are satisfied with the grade before you shuffle things around. Bob . . . ========================= Use utilities Day ================================================ - MATRONICS WEB FORUMS ================================================ - List Contribution Web Site sp; ================================================== ________________________________________________________________________________
Subject: Air Pathways Intercom
From: "Noplugs" <qas44n(at)yahoo.com>
Date: Feb 09, 2010
I have come across an "Air Pathways AP120" Intercom. Does anyone use one of these? And can anyone help me with a copy of the installation manual & schematic? Thanks Read this topic online here: http://forums.matronics.com/viewtopic.php?p=285763#285763 ________________________________________________________________________________
Date: Feb 09, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Aux Alternator B Lead, Battery Buss
At 05:17 PM 2/9/2010, you wrote: >Thanks for this Bob. > >I am trying to do my homework. I am not an electrical engineer and >have profited a great deal from what is written here. I guess I >don't clearly understand what happens to some of the components in a fail mode. > >So the first question is, where does the B-lead from the aux alt >go? If it is connected with the main alt B-lead to the starter side >of the main contactor, then the failure mode goes like this: Which Z-figure, if any, are you considering. > >1. Main alt fails, turn off it's field and turn on the aux >alt. Shed load to 80% of the aux alternator rating (80%X20 amp= 16 amp max). v The 80% rule is about maintaining some "excess" capability for the recharging of batteries. If you've had a main alternator failure then getting comfortably on the ground is the mission of the moment. Use 100% of the aux alternator if necessary . . . plus what ever is in the battery to boot. What are your "get down comfortably loads" as compared to your aux alternator size? >2. If the main contactor fails open, will the main alternator function okay? Probably but not guaranteed. Does your airplane have a hydraulic pump . . . or klieg lights for landing? >3. If the battery shorts ( a rare occurrence, to be sure) then open >the main contactor. Does the main alt work okay? RB batteries very rarely short . . . during the time the 5-cell battery is connected to the bus, the alternator is stuffing 14v into a 11.8 volt system . . . the loadmeter (if installed will show abnormally high amps while bus volts are low. This condition is not stable. As the battery dries up, the voltage will rise and the current may go down a bit. This is so rare with an RG battery that what ever diagnostic and reaction plans you have concocted for such an event will probably have been forgotten. >4. Main alt fails followed by a failure of the battery >contactor. Are we still okay? That's a dual failure on a single flight. Also depends on what z-figure you're talking about. > >If the aux alt is connected to the battery side of the battery contactor: Don't recommend that for the SD-20 . . . that's fraught with the same issues as the previously published and recently withdrawn Z-13/20. If you have an SD-20, go with a Z-12 emulation and put the aux alternator on the ship-side of the battery contactor. > >1. Main alt fails, turn off it's field and turn on the aux >alt. Shed load to 80% of the aux alternator rating (80%X20 amp= 16 >amp max). Not a problem >2. If the main contactor fails open, will the main alt still be okay >or do I switch to the aux alternator because it has a direct battery >connection? >3. If the battery shorts, that should burn out the fuse between the >aux alternator B-lead if that alternator is being used. Is the main >still functional? > >The question I am getting to, I think, is how does the system >perform if the battery is out of the circuit either because the main >contactor fails or we have to open it to free us from a failed >battery. Back to my original question. Where should the aux >alternator B-lead go and why? If it were my airplane, Z-13/8 is the lightest, simplest, least expensive way to get SYSTEM reliability not offered by the majority of TC aircraft. Just how close Vertical Power comes to emulating Z-13/8 performance has not been fully explored by me . . . Marc would be your authority on that. But as I mentioned above, an SD-20 should be paired with the SB-1 regulator, connected to the main bus and adjusted for 13.0 volts. Operate per B&C instructions. Bob . . . ________________________________________________________________________________
From: <flylists(at)dbarrett.net>
Subject: Pitot heat relays
Date: Feb 10, 2010
I've been looking at relays for pitot heat and landing lights, and have found several that look to me like they might work. 20A should be sufficient but the 40A version has mounting tabs to secure them behind the panel. Here are representative specs: http://www.azettler.com/pdfs/az977.pdf http://www.azettler.com/pdfs/az973.pdf http://www.azettler.com/pdfs/az9731.pdf http://www.azettler.com/index.php?id=electromechanical_relays_other2 Are there specific things I should be concerned about when specifying relays for this application? Is a sealed relay recommended in the cockpit? Resistors/diodes across the coil are available but not generally in stock. (I can add the diode if necessary here.) The cost is < $2 in single units from: http://www.onlinecomponents.com http://www.onlinecomponents.com/buy/AMERICAN-ZETTLER/AZ9731-1A-12DC1/ They have a $35 minimum order, but I'm sure I can find other things to fill out the order. David Barrett ________________________________________________________________________________
From: "Vern Little" <sprocket@vx-aviation.com>
Subject: Re: Pitot heat relays
Date: Feb 10, 2010
These are standard automotive relays. If you don't want to place the minimum order, pick one up at your favorite auto parts store. I use devices that have internal resistors (or diodes) because it saves a bit of wiring-- but have 14 of them in my aircraft [another long topic about switch failures vs relay reliability]. You can also purchase relay sockets that make installation a bit easier, if you wish. Vern Little Vx Aviation -------------------------------------------------- From: <flylists(at)dbarrett.net> Sent: Wednesday, February 10, 2010 7:26 AM Subject: AeroElectric-List: Pitot heat relays > > I've been looking at relays for pitot heat and landing lights, and have > found several that look to me like they might work. 20A should be > sufficient > but the 40A version has mounting tabs to secure them behind the panel. > Here > are representative specs: > > http://www.azettler.com/pdfs/az977.pdf > http://www.azettler.com/pdfs/az973.pdf > http://www.azettler.com/pdfs/az9731.pdf > http://www.azettler.com/index.php?id=electromechanical_relays_other2 > > Are there specific things I should be concerned about when specifying > relays > for this application? Is a sealed relay recommended in the cockpit? > Resistors/diodes across the coil are available but not generally in stock. > (I can add the diode if necessary here.) The cost is < $2 in single units > from: > http://www.onlinecomponents.com > http://www.onlinecomponents.com/buy/AMERICAN-ZETTLER/AZ9731-1A-12DC1/ > They have a $35 minimum order, but I'm sure I can find other things to > fill > out the order. > > David Barrett > > > > Checked by AVG - www.avg.com > 07:35:00 > ________________________________________________________________________________
From: "John Burnaby" <jonlaury(at)impulse.net>
Subject: Re: RE: Starter engaged light, was Starter and contactor
Date: Feb 10, 2010
Hello OB, The switch has an independently switched lamp. So the lamp does not necessarily go on when the starter is activated. As stated, I plan to connect one pole of my dpst switch, through the switch, to the lamp for the test circuit. The hung starter circuit is in parallel with the test circuit, but derives power from the fat wire between starter solenoid and starter. John ________________________________________________________________________________
Subject: Re: Pitot heat relays
From: "pestar" <peter(at)reivernet.com>
Date: Feb 10, 2010
Vern What manufacturers relays are you using where the diodes are built in? Thanks Peter Armstrong Auckland, New Zealand Read this topic online here: http://forums.matronics.com/viewtopic.php?p=285873#285873 ________________________________________________________________________________
From: BobsV35B(at)aol.com
Date: Feb 10, 2010
Subject: Re: RE: Starter engaged light, was Starter and contactor
Sounds Fair To Me!! Happy Skies, Old Bob In a message dated 2/10/2010 1:02:32 P.M. Central Standard Time, jonlaury(at)impulse.net writes: Hello OB, The switch has an independently switched lamp. So the lamp does not necessarily go on when the starter is activated. As stated, I plan to connect one pole of my dpst switch, through the switch, to the lamp for the test circuit. The hung starter circuit is in parallel with the test circuit, but derives power from the fat wire between starter solenoid and starter. John (http://www.matronics.com/Navigator?AeroElectric-List) (http://www.matronics.com/contribution) ________________________________________________________________________________
Subject: Re: Pitot heat relays
From: "user9253" <fran4sew(at)banyanol.com>
Date: Feb 11, 2010
Both Digikey and Mouser have diodes and relays. Search their websites for this part number: G8JN-1C6T-F-DC12 made by Omron. It has a metal one-hole mounting bracket and is weather proof. Here is the data sheet: http://www.components.omron.com/components/web/PDFLIB.nsf/0/39018354E59A56C985257201007DD68C/$file/G8JN_0607.pdf I thought it interesting that the normally open contacts have a higher current rating than the normally closed contacts, maybe because magnetism closes contacts quicker and tighter with less bounce than a spring does. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=285935#285935 ________________________________________________________________________________
Date: Feb 11, 2010
From: D <dfritzj(at)yahoo.com>
Subject: Re: Pitot heat relays
I got mine from Waytek. I think they were Bosch. Dan ________________________________________________________________________________
Date: Feb 11, 2010
From: paul wilson <pwmac(at)sisna.com>
Subject: Re: Pitot heat relays
Ford uses N2 filled, diode internal relays used for the glow plugs. A handy source. I would have to check, but I bet NAPA sells the identical part for less $$?? Paul ======= At 06:19 AM 2/11/2010, you wrote: > >Both Digikey and Mouser have diodes and relays. Search their >websites for this part number: G8JN-1C6T-F-DC12 made by Omron. It >has a metal one-hole mounting bracket and is weather proof. Here is >the data sheet: >http://www.components.omron.com/components/web/PDFLIB.nsf/0/39018354E59A56C985257201007DD68C/$file/G8JN_0607.pdf >I thought it interesting that the normally open contacts have a >higher current rating than the normally closed contacts, maybe >because magnetism closes contacts quicker and tighter with less >bounce than a spring does. >Joe > >-------- >Joe Gores > > >Read this topic online here: > >http://forums.matronics.com/viewtopic.php?p=285935#285935 > > ________________________________________________________________________________
From: "Vern Little" <sprocket@vx-aviation.com>
Subject: Re: Pitot heat relays
Date: Feb 11, 2010
Here's what I'm using: Digikey 255-2161-ND They have the built-in resistors. Standard automotive type. Not having to wire in the diodes/resistors is a big bonus. Also, the coils are polarity insensitive when using resistors rather than diodes, if that matters. Vern -------------------------------------------------- From: "pestar" <peter(at)reivernet.com> Sent: Wednesday, February 10, 2010 1:07 PM Subject: AeroElectric-List: Re: Pitot heat relays > > Vern > > What manufacturers relays are you using where the diodes are built in? > > Thanks > Peter Armstrong > Auckland, New Zealand > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=285873#285873 > > > > Checked by AVG - www.avg.com > 07:35:00 > ________________________________________________________________________________
From: "Jim Thorne" <rv7a(at)cox.net>
Subject: Warm Alternator
Date: Feb 11, 2010
Had an interesting discovery today. I was charging the battery on my RV-7A and had the Master on and the Dynon Flt-Dek 180 on while I was doing some calibrations. When I got out of the airplane I felt the alternator an it was warm to the touch. When I turned the Master and Dynon off it soon dropped to ambient temp. Do I have something wrong in my wiring? Or would this be normally expected given the circumstances described. I have wired the plane in accordance with the Z-13 diagram but have the internally regulated alternator until I need to change it. Jim Thorne ________________________________________________________________________________
Date: Feb 11, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Warm Alternator
At 07:21 PM 2/11/2010, you wrote: >Had an interesting discovery today. I was charging the battery on >my RV-7A and had the Master on and the Dynon Flt-Dek 180 on while I >was doing some calibrations. When I got out of the airplane I felt >the alternator an it was warm to the touch. When I turned the >Master and Dynon off it soon dropped to ambient temp. Do I have >something wrong in my wiring? Or would this be normally expected >given the circumstances described. I have wired the plane in >accordance with the Z-13 diagram but have the internally regulated >alternator until I need to change it. If the bus is hot and the engine not running and assuming further that the alternator's internal regulator is not fitted with a "stationary alternator detection system" then the regulator will run the field at full bus voltage and draw about 3 amps. This is on the order of 40-50 watts of heat being dissipated within the alternator. If Z-13, then do you have absolute control of the alternator via the ity-bity wire that goes into the back of the alternator? Was your master switch fully ON (BATT + ALT) or just up to the mid (BATT ONLY) position? Bob . . . ________________________________________________________________________________
From: "Bob Leffler" <rv(at)thelefflers.com>
Subject: OVM-14 and VP-200 Ground Power Plug
Date: Feb 12, 2010
I was looking for the OVM-14 module on B&C's website to use per Vertical Power's recommendation for a ground power plug. It appears to not be available from B&C. I did find old links through google, but those pages have been removed. I sent off a inquiry to B&C, but haven't received a response from them. Any suggestions on an alternative device? This link will take to you want I'm attempting to do: http://www.verticalpower.com/docs/GPP.pdf Thanks, Bob ________________________________________________________________________________
Subject: Eliminate the Starter Contactor?
From: "AVick" <ajvick49(at)gmail.com>
Date: Feb 12, 2010
Bob, I have a B&C starter with the attached solenoid. The solenoid ( which is attached to the case of the starter) has a wire from the starter to the solenoid. I would like to cut the jumper wire to the solenoid and wire that wire directly to the starter switch there by eliminating the need for the starter contactor relay. Will that work? Or should I still use the starter contactor relay. I have several A&P's tell me the starter contactor is not needed. They said wire the starter switch directly to the starter solenoid. Another party said I would get an amp surge from the starter solenoid back to my starter switch and it would cause premature failure of the starter switch contacts. So what is the answer? Thanks, Alan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286158#286158 ________________________________________________________________________________
Subject: OVM-14 and VP-200 Ground Power Plug
Date: Feb 12, 2010
From: "George, Neal E Capt USAF ACC 505 TRS/DOJ" <Neal.George(at)hurlburt.af.mil>
Bob - I may have a spare. I'll check this afternoon and let you know... neal =============== I was looking for the OVM-14 module on B&C's website to use per Vertical Power's recommendation for a ground power plug. It appears to not be available from B&C. I did find old links through google, but those pages have been removed. I sent off a inquiry to B&C, but haven't received a response from them. Any suggestions on an alternative device? This link will take to you want I'm attempting to do: http://www.verticalpower.com/docs/GPP.pdf Thanks, Bob ________________________________________________________________________________
Subject: Re: Battery desulfators . . .
From: Ian <ixb(at)videotron.ca>
Date: Feb 12, 2010
It was listed as a "non-aviation" device, but I'd be interested in your comments on it. http://www.aircraftspruce.com/catalog/elpages/batteryminder11-11671.php Ian ----Original Message----- From: Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com> Subject: Re: AeroElectric-List: Battery desulfators . . . Date: Fri, 05 Feb 2010 14:42:28 -0600 At 11:19 AM 2/5/2010, you wrote: A gentleman behind the counter at Aircraft Spruce Canada told me that he'd been using a trickle charger/de-sulphator for twelve years on the same battery. Based on that, I put my trust in his word and purchased one. What brand/model is it? I do not doubt his experience. I only question the analysis for cause/effect and performance. The fact that his battery might still get an engine started is not a good quantifier of stored energy. Cranking a typical piston engine from a battery takes perhaps 2% of the battery's total energy. Of course the only test of whether it's going to be doing it's job is a discharge test, rather than blind faith. You are correct in your suggestion that a deep-discharge cap-checks and perhaps load-testing are the true measure of battery capability. It's currently maintaining the charge on the bench while I'm away for the winter. I have a feeling that a de-sulphator might be better used for maintenance than for attempting to recover a heavily crystallized battery. If any of this in any way disagrees with anything Guru Nuckolls says, then take his advice!! It would be interesting to see what technology is offered in his 12+ years old device. If it's a true "trickle" charger, then it's an SLVA battery killer. The maintainers and smart chargers I have in my shop behave like . . . http://www.aeroelectric.com/Pictures/Curves/Battery_Tender_Recharge.pdf http://www.aeroelectric.com/Pictures/Curves/Battery_Minder_Recharge.pdf http://www.aeroelectric.com/Pictures/Curves/schumacher_2.jpg and http://www.aeroelectric.com/Pictures/Curves/schumacher_5.jpg Note in the fourth trace, there's a lot of "noise" on the data . . . it may well be that this charger has a feature designed to electrically "shake up" battery chemistry with some notion of preventing or reversing sulfation growth. I have some examples in my family of instrumentation batteries that still cap-check at 85+ percent of new after 6 years . . . so it seems that having a useful device after 12 years in similar storage may not be a stretch. If you check out the dozens of patents on devices that claim to rescue fair batteries in distress from the clutches of evil Dr. Sulfation, their approaches and explanations are all over the map. A search at http://freepatentsonline.com for . . . desulfator + battery + charger . . . yielded 38 hits. I've not read them in detail but keep in mind that for one to receive a patent, the process/hardware depicted must be UNIQUE. So in one resource alone we are made privy to 38 different approaches. Keep in mind also that the granting of a patent is no guarantee that the thing performs as advertised. I'm not suggesting that one or more such devices are not useful in some manner. I just don't KNOW. I DO suggest that MOST of what's offered is like putting magnets on your car's fuel lines to raise the octane of the gasoline as it passes by . . . If anyone has a real world solution to extending battery life by way of staving off or reversing sulfation, it's not yet apparent to me. I'm participating in the evaluation and commercialization of a remarkably innovative lead-acid aircraft battery that promises weight reduction and improved performance to boot. As soon as the business details of the program are finalized, I'll be able to talk about it more. However, The real bonus for me is an opportunity to know the chemistry gurus who are supporting the program. Battery sulfation and DE-SULFATION will be among numerous topics I'd like to discuss. Bob . . . ________________________________________________________________________________
Date: Feb 12, 2010
From: Dan Brown <dan(at)familybrown.org>
Subject: Mini blade fuses
I'm installing a few electronic devices in the Mooney that call for inline fuses as circuit protection. I've never been a fan of the inline glass fuse holders, so I'm looking at inline blade fuse holders instead. Then, since smaller is better (or so I think), I'm specifically looking at the mini blade fuse holders. The problem is that these devices specify a fuse rating of one amp (or sometimes less), and the smallest mini blade fuses I'm finding are 2 amps. I don't think that will really be harmful, but I want to follow the instructions as closely as possible. So, with that explanation, are there sources of one-amp or lower rated mini blade fuses? ________________________________________________________________________________
Date: Feb 12, 2010
From: Harley <harley(at)AgelessWings.com>
Subject: Re: Mini blade fuses
Yep...the fuse manufacturer Littlefuse lists them, so I would guess that you can find them at anyplace that sells their fuses...a quick Google search found them at Mouser ( http://tinyurl.com/yh2z8zp ) and a dozen smaller online stores for around 25-35 cents each. Harley ------------------------------------------------------------------------ Dan Brown wrote: > > I'm installing a few electronic devices in the Mooney that call for > inline fuses as circuit protection. I've never been a fan of the > inline glass fuse holders, so I'm looking at inline blade fuse holders > instead. Then, since smaller is better (or so I think), I'm > specifically looking at the mini blade fuse holders. > > The problem is that these devices specify a fuse rating of one amp (or > sometimes less), and the smallest mini blade fuses I'm finding are 2 > amps. I don't think that will really be harmful, but I want to follow > the instructions as closely as possible. > > So, with that explanation, are there sources of one-amp or lower rated > mini blade fuses? > > ________________________________________________________________________________
From: "B Tomm" <fvalarm(at)rapidnet.net>
Subject: Mini blade fuses
Date: Feb 12, 2010
See http://www.bandc.biz/circuit-protective-devices.aspx Also see digikey.com etc Bevan ________________________________________________________________________________
Date: Feb 12, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: OVM-14 and VP-200 Ground Power Plug
At 10:21 AM 2/12/2010, you wrote: >I was looking for the OVM-14 module on B&C's website to use per >Vertical Power's recommendation for a ground power plug. It >appears to not be available from B&C. I did find old links through >google, but those pages have been removed. I sent off a inquiry to >B&C, but haven't received a response from them. > >Any suggestions on an alternative device? This link will take to >you want I'm attempting to >do: ><http://www.verticalpower.com/docs/GPP.pdf>http://www.verticalpower.com/docs/GPP.pdf They've discontinued individual sales of the crowbar ovm. We've re-tooled and offer the device. A new batch is in production right now. See: https://matronics.com/aeroelectric/Catalog/AECcatalog.html Bob . . . ________________________________________________________________________________
Date: Feb 12, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Mini blade fuses
At 03:01 PM 2/12/2010, you wrote: > >I'm installing a few electronic devices in the Mooney that call for >inline fuses as circuit protection. I've never been a fan of the >inline glass fuse holders, so I'm looking at inline blade fuse >holders instead. Then, since smaller is better (or so I think), I'm >specifically looking at the mini blade fuse holders. > >The problem is that these devices specify a fuse rating of one amp >(or sometimes less), and the smallest mini blade fuses I'm finding >are 2 amps. I don't think that will really be harmful, but I want >to follow the instructions as closely as possible. > >So, with that explanation, are there sources of one-amp or lower >rated mini blade fuses? 1A is as small as I've ever seen . . . and most auto-stores only stock them down to 3A. 1A and 2A were part of the inventory I sold B&C some years ago. They appear on their website at: http://www.bandc.biz/atctypefuse.aspx Bob . . . ________________________________________________________________________________
Date: Feb 12, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Eliminate the Starter Contactor?
At 11:27 AM 2/12/2010, you wrote: > >Bob, >I have a B&C starter with the attached solenoid. The solenoid ( >which is attached to the case of the starter) has a wire from the >starter to the solenoid. I would like to cut the jumper wire to the >solenoid and wire that wire directly to the starter switch there by >eliminating the need for the starter contactor relay. Will that >work? Or should I still use the starter contactor relay. I have >several A&P's tell me the starter contactor is not needed. They >said wire the starter switch directly to the starter >solenoid. Another party said I would get an amp surge from the >starter solenoid back to my starter switch and it would cause >premature failure of the starter switch contacts. So what is the answer? See: http://aeroelectric.com/articles/strtctr.pdf Bob . . . ________________________________________________________________________________
Date: Feb 12, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Battery desulfators . . .
At 11:42 AM 2/12/2010, you wrote: >It was listed as a "non-aviation" device, but I'd be interested in >your comments on it. ><http://www.aircraftspruce.com/catalog/elpages/batteryminder11-11671.php>http://www.aircraftspruce.com/catalog/elpages/batteryminder11-11671.php The Battery Minders and Battery Tenders are both quite suitable for any 12V lead acid battery . . . whether it's used in an airplane or your garden tractor. Bob . . . ________________________________________________________________________________
Date: Feb 12, 2010
From: Ken <klehman(at)albedo.net>
Subject: Re: Warm Alternator
About 4 years ago I mentioned the same thing with my new Nippondenso 40 amp alternator. If the IGN wire (itty- bitty wire) is powered up then my alternator indeed draws field current from the B+ terminal. Obviously it can't draw any current when the OV contactor is switched off to disconnect both the B+ line and the IGN wire from the battery. Some alternators also seem to draw a mA or so of standby current from the B+ lead. Anyway the OV contactor eliminates all current draw if the aircraft sits for long periods or if there is an internal alternator problem. 320 happy and worry free hours on it so far. Ken Robert L. Nuckolls, III wrote: > At 07:21 PM 2/11/2010, you wrote: >> Had an interesting discovery today. I was charging the battery on my >> RV-7A and had the Master on and the Dynon Flt-Dek 180 on while I was >> doing some calibrations. When I got out of the airplane I felt the >> alternator an it was warm to the touch. When I turned the Master and >> Dynon off it soon dropped to ambient temp. Do I have something wrong >> in my wiring? Or would this be normally expected given the >> circumstances described. I have wired the plane in accordance with >> the Z-13 diagram but have the internally regulated alternator until I >> need to change it. > > If the bus is hot and the engine not running and > assuming further that the alternator's internal > regulator is not fitted with a "stationary alternator > detection system" then the regulator will run the > field at full bus voltage and draw about 3 amps. > This is on the order of 40-50 watts of heat > being dissipated within the alternator. If Z-13, > then do you have absolute control of the alternator > via the ity-bity wire that goes into the back of > the alternator? Was your master switch fully ON > (BATT + ALT) or just up to the mid (BATT ONLY) > position? > > Bob . . . > ________________________________________________________________________________
Date: Feb 13, 2010
From: Dan Brown <dan(at)familybrown.org>
Subject: Re: Mini blade fuses
On 2/12/10 9:13 PM, Robert L. Nuckolls, III wrote: > inventory I sold B&C some years ago. They appear on their > website at: > > http://www.bandc.biz/atctypefuse.aspx These are the ATC fuses, and I was actually looking for the ATM--but what I'm finding at Mouser and such for 1A ATM fuses requires a large order and a long lead time. ATC it is, then. Thanks! ________________________________________________________________________________
Subject: Basic Electricity....Grrrrr.........
From: "Eric M. Jones" <emjones(at)charter.net>
Date: Feb 13, 2010
Perhaps the stars are misaligned, but I keep getting calls like this: "I bought your PowerSchottky Diode and it has voltage both ways. Don't you check this stuff before sending it out?..." "I bought your Powerlink Jr. III 35 amp relay and it won't turn (on or)off...the output still has voltage..." I could go on. I often forget that in the "basic electricity" world the existence of a voltage is presumed by many to mean something is ON. I need to include a "This means nothing at all" note in my instruction manuals. Solid state devices often use "pull-down" (or pull-up) resistors to prevent outputs from "floating". But this is done to prevent odd things from happening-- not usually to prevent voltmeters from reading something silly. Now this is not a unique characteristic of solid state devices. Any typical electromechanical relay will have some voltage on its power output lugs whether it is on or off, only the impedance will be different. A voltmeter with no load is pretty useless (but hey, it could be made to give nonsensical readings on those ghost-hunter shows). -------- 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=286277#286277 ________________________________________________________________________________
Date: Feb 13, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Basic Electricity....Grrrrr.........
At 10:26 AM 2/13/2010, you wrote: Perhaps the stars are misaligned, but I keep getting calls like this: "I bought your PowerSchottky Diode and it has voltage both ways. Don't you check this stuff before sending it out?..." "I bought your Powerlink Jr. III 35 amp relay and it won't turn (on or)off...the output still has voltage..." I could go on. I often forget that in the "basic electricity" world the existence of a voltage is presumed by many to mean something is ON. I need to include a "This means nothing at all" note in my instruction manuals. Solid state devices often use "pull-down" (or pull-up) resistors to prevent outputs from "floating". But this is done to prevent odd things from happening-- not usually to prevent voltmeters from reading something silly. Now this is not a unique characteristic of solid state devices. Any typical electromechanical relay will have some voltage on its power output lugs whether it is on or off, only the impedance will be different. A voltmeter with no load is pretty useless (but hey, it could be made to give nonsensical readings on those ghost-hunter shows). May I suggest some words in your download/handout literature that speaks to errors of deduction that arise from errors of measurement? Some simple test procedures can stand off many unhappy returns from customers that do not understand the physics of our art. While multi-meters still had pointers moving over scale plates behind glass, there was no such thing as a VOLT METER. The meters were in fact sensors of current. They could be made to display voltage by placing a resistor in series with the instrument. E.g. a 0-1 milliampere meter movement might be placed in series with a 20K resistor and be fitted with a scale plate that reads from 0 to 20 volts. With a sensitivity of 1000 ohms/volt, this device would have yielded better data for your un-educated customers. During this same era, we had to go out of our way to craft voltmeters with VERY high sensitivities (Vacuum Tube Voltmeters) that would not load a voltage node driven by a particularly high impedance. Even with all the accuracy and non-loading effects of modern digital voltmeters at DC, they present a whole NEW problem when attempting the measure voltage at nodes where there are radio frequency components riding on the DC. The old VTVM had a resistor (1 to 10 megohms) built into the probe right at the tip. The modern digital meter expects to tell you what the voltage is a end ends of some long wire leads. I have adapted a 'scope probe to a 3/4" banana plug such that I can scale any of several digital meters by a factor of 10 while taking advantage of the very low capacitance/high resistance loads presented by the 'scope probe. Our customer base is the amateur airplane builder. By definition, they're NOT professionals in the broad spectrum of skill sets applicable to the task. Hence, the events you've cited should be expected on some level. I'm disappointed to report that the ranks of those who truly understand the physics of our art are getting pretty thin . . . even amongst professionals with credentials that suggest otherwise. The market we have is the market we have. We can choose to service it with what's necessary and useful to move the various projects ahead or . . . the alternatives are obvious. Bob . . . ________________________________________________________________________________
Subject: GPU for Piper
Date: Feb 13, 2010
From: "Chuck Jensen" <cjensen(at)dts9000.com>
Does anyone know of an (relatively) inexpensive source for a ground power unit (GPU) that can be plugged into the wall that can be used for powering a plane's panel, such as a Piper Meridian or Malibu for doing armchair flying to sort through GPS controls, et al? Piper wants 2-3 thousand, which seems pricey, by not surprising. Surely there is a more man's substitute available? Chuck Jensen ________________________________________________________________________________
Subject: Z-13 question
From: "jonlaury" <jonlaury(at)impulse.net>
Date: Feb 13, 2010
I have an all-electric airplane and am using Z-13 with a 40a stby alt. All mandatory engine power (EFI, IGN, etc) is on the battery bus As I understand Z-13, if the battery has a short , it takes down the battery bus, the redundant alternators notwithstanding, as there is no disconnect from the battery/batt bus. It seems that putting a DPST ON-ON switch between Batt Bus and Batt position & Alt 2 position would allow one to isolate a problematic battery and supply Alt 2 power to the Batt Bus and keeping the prop going round. I recognize that this defeats the bonehead-proof design of a hot battery bus, but adds an option should there be a battery problem. I'm not sure if it's a benefit or not. I would wire the two switch poles together to the batt buss, both sides of position one to the battery, both sides of position 2 to Alt 2. I think I'm buying some switch redundancy with a DPST. What do you all think? John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286296#286296 ________________________________________________________________________________
From: "Bruce Gray" <bgray(at)glasair.org>
Subject: GPU for Piper
Date: Feb 13, 2010
A 28v/30a regulated power supply and a jumper cable should be all that is needed. My PS is manufactured by Astron. (VLS 35M, about $400) http://www.astroncorp.com/showpage.asp?p=6 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 Chuck Jensen Sent: Saturday, February 13, 2010 1:15 PM Subject: AeroElectric-List: GPU for Piper Does anyone know of an (relatively) inexpensive source for a ground power unit (GPU) that can be plugged into the wall that can be used for powering a plane's panel, such as a Piper Meridian or Malibu for doing armchair flying to sort through GPS controls, et al? Piper wants 2-3 thousand, which seems pricey, by not surprising. Surely there is a more man's substitute available? Chuck Jensen ________________________________________________________________________________
From: "B Tomm" <fvalarm(at)rapidnet.net>
Subject: Z-13 question
Date: Feb 13, 2010
John, I don't think it's a good idea. I don't believe that a "short" is a failure mode for a battery that you should be concerned with because it is too rare especially on a well maintained battery. Perhaps you meant a single shorted cell, while also rare but if it did happen, would still produce enough current at an acceptable voltage to run EFI, or so I believe. Adding switches or relays to add control of the battery bus obviously adds failure points which I think would be orders of magnitude more likely than a "shorted" battery. If your main alternator (electrical energy generator) fails, the battery (electrical energy reservoir) is a short term back up and should be sized to power your essential loads longer than your total onboard fuel supply. You have a second alternator, so that is your indefinite backup (in my opinion). If your battery is always maintained and replaced regularly, I don't think you will ever go without sufficient electrons at-the-ready. My opinions only. Others may disagree. Bevan -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of jonlaury Sent: Saturday, February 13, 2010 10:51 AM Subject: AeroElectric-List: Z-13 question --> I have an all-electric airplane and am using Z-13 with a 40a stby alt. All mandatory engine power (EFI, IGN, etc) is on the battery bus As I understand Z-13, if the battery has a short , it takes down the battery bus, the redundant alternators notwithstanding, as there is no disconnect from the battery/batt bus. It seems that putting a DPST ON-ON switch between Batt Bus and Batt position & Alt 2 position would allow one to isolate a problematic battery and supply Alt 2 power to the Batt Bus and keeping the prop going round. I recognize that this defeats the bonehead-proof design of a hot battery bus, but adds an option should there be a battery problem. I'm not sure if it's a benefit or not. I would wire the two switch poles together to the batt buss, both sides of position one to the battery, both sides of position 2 to Alt 2. I think I'm buying some switch redundancy with a DPST. What do you all think? John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286296#286296 ________________________________________________________________________________
Subject: GPU for Piper
Date: Feb 13, 2010
From: "Chuck Jensen" <cjensen(at)dts9000.com>
Thanks, Bruce...but then, I suppose one has to hook that up to the Piper plug, which is only overpriced by about double. Nonetheless, your link was a good one. Thanks, Chuck Jensen Diversified Technologies 2680 Westcott Blvd Knoxville, TN 37931 Phn: 865-539-9000 x100 Cell: 865-406-9001 Fax: 865-539-9001 cjensen(at)dts9000.com -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Bruce Gray Sent: Saturday, February 13, 2010 2:29 PM Subject: RE: AeroElectric-List: GPU for Piper A 28v/30a regulated power supply and a jumper cable should be all that is needed. My PS is manufactured by Astron. (VLS 35M, about $400) http://www.astroncorp.com/showpage.asp?p=6 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 Chuck Jensen Sent: Saturday, February 13, 2010 1:15 PM Subject: AeroElectric-List: GPU for Piper Does anyone know of an (relatively) inexpensive source for a ground power unit (GPU) that can be plugged into the wall that can be used for powering a plane's panel, such as a Piper Meridian or Malibu for doing armchair flying to sort through GPS controls, et al? Piper wants 2-3 thousand, which seems pricey, by not surprising. Surely there is a more man's substitute available? Chuck Jensen ________________________________________________________________________________
From: "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net>
Subject: GPU for Piper
Date: Feb 13, 2010
==> AeroElectric-List message posted by: "Chuck Jensen" Does anyone know of an (relatively) inexpensive source for a ground power unit (GPU) that can be plugged into the wall that can be used for powering a plane's panel, such as a Piper Meridian or Malibu for doing armchair flying to sort through GPS controls, et al? Piper wants 2-3 thousand, which seems pricey, by not surprising. Surely there is a more man's substitute available Chuck, If I understand correctly, that you want to operate the electronics without the engine running. If this is the case, why not just connect a battery maintainer to your battery, plug it in, and it will keep your battery at full charge while running the electronics, provided you have a maintainer with enough capacity. I would assume you would not need more than about 10 amps, so it would not take a very large unit to accomplish this task. Roger ________________________________________________________________________________
Date: Feb 13, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: GPU for Piper
At 08:08 PM 2/13/2010, you wrote: >Not sure if this is actually relevant to the original question but I >bought the Cole Hersee Piper style socket and plug from Aircraft >Spruce after reading Bob N's article on modifying for our OBAM aircraft. > >ACS catalog page: ><http://www.aircraftspruce.com/pdf/2010Individual/Cat10463.pdf>http://www.aircraftspruce.com/pdf/2010Individual/Cat10463.pdf > >AeroElectric connection article: ><http://www.aeroelectric.com/articles/grndpwr.pdf>http://www.aeroelectric.com/articles/grndpwr.pdf > >Socket and plug seemed kind of heavy to me? Socket was 10 oz. and >plug was 7.2 oz. I guess I really might not have needed the plug as >FBO is supposed to have this on his "battery cart?" Yup . . . that's the general rule. Actually, the "Piper" connector is a lighter, lower cost alternative to the AN2551 found on other brands and the heavier Piper aircraft. The C.H. 11041 and mating connector was originally created for the ground based vehicles market like OTR trucks and electric fork-lifts. I've used this connector on several 100+ AMP test systems for really BIG motors. To my knowledge, Piper was the only folk who used this connector on the lighter singles. I'm pretty sure all Brand C and Brand B airplanes used the AN2551. Any FBO worth his ground power revenues will have both. Bob . . . ________________________________________________________________________________
From: "Bob McCallum" <robert.mccallum2(at)sympatico.ca>
Subject: Z-13 question
Date: Feb 14, 2010
John; See embedded comments. These are not intended in any way to be "smart assed" just trying to illustrate my personal opinion and understanding of the question. > -----Original Message----- > From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list- > server(at)matronics.com] On Behalf Of jonlaury > Sent: Saturday, February 13, 2010 1:51 PM > To: aeroelectric-list(at)matronics.com > Subject: AeroElectric-List: Z-13 question > > > I have an all-electric airplane and am using Z-13 with a 40a stby alt. All mandatory > engine power (EFI, IGN, etc) is on the battery bus > > As I understand Z-13, if the battery has a short(with a modern properly maintained AGM/VRLA battery this is about as likely as the engine mount falling off) , it takes down the battery bus, the > redundant alternators notwithstanding, as there is no disconnect from the > battery/batt bus. ( not quite true as the battery with a shorted cell (which doesn't happen) will likely still supply sufficient power to keep the engine running especially when supported by an operating alternator. If the alternator has sufficient reserve capacity it will "cook" the battery but all of this will take some time giving you ample opportunity to safely land) It seems that putting a DPST ON-ON switch between Batt Bus and > Batt position & Alt 2 position would allow one to isolate a problematic battery and > supply Alt 2 power to the Batt Bus and keeping the prop going round. (assuming your particular alternator will function without a battery, and you don't switch a load which stalls it) > > I recognize that this defeats the bonehead-proof design of a hot battery bus, but adds > an option should there be a battery problem. I'm not sure if it's a benefit or not. In my opinion it's not. > > I would wire the two switch poles together to the batt buss, both sides of position > one to the battery, both sides of position 2 to Alt 2. I think I'm buying some switch > redundancy with a DPST. (and when one pole of the switch fails ON how does the second pole help you turn it off??) > > What do you all think? I think it's a bad idea to play with a tried and true design which has had a lot of thought about failure modes put into it and try to second guess what "might" happen. Most of the "Z" figures represent electrical systems which are so superior to anything found in the average "production vehicle" (be it airborne or ground based) that your worries are unfounded. Batteries don't magically "fail", engines don't just fall off, prop bolts don't shear. All of these failures are so rare as to be ignored. That's not to say that batteries shouldn't be maintained and tested, engine mount integrity examined and prop bolts checked, but these failure possibilities don't warrant backups. (How would you propose to backup an engine mount for example? You just have to trust that it won't fail.) > > John > > Bob McC ________________________________________________________________________________
Subject: GPU for Piper
Date: Feb 14, 2010
From: "Chuck Jensen" <cjensen(at)dts9000.com>
Roger, Yes, exactly. the G1000 has a ton of features, but they are only useful if one knows how to find them. The mechanical part can be read in the manual, but the reflexive part can only be learned through arm-chair flying, so powering the panel is the objective. Your battery charger/minder idea is a good one, but I don't know how much load can be shed to reduce amp draw. During normal operations, it's pretty high at 67 amps, but that's with a bunch of accessories and lights running. Perhaps the G1000 load will be <10 amp, but something less than 20 amps is probably in a safe range. I want to be able to use the same power source for powering the panel and then, setting it (or having it smart enough) to go to 1 amp for trickle charging the battery longer term. I certainly don't want to damage the battery by overcharging, since the replacement cost implies that Piper has replaced the convention lead-acid battery with a gold-acid battery. So, the task is to find a 110v input charger that will output 20 amp 24V for arm-chair flying but is smart enough to go to 1 amp long term charging rate, the max recommended for the Concorde 38AH battery, when used for battery charging or topping off. Are bigger versions of some of the battery minders discussed here appropriate for the task? Apologies for asking others to do my homework, but it's frustrating to know just enough about an issue to have doubts. Chuck Jensen Chuck, If I understand correctly, that you want to operate the electronics without the engine running. If this is the case, why not just connect a battery maintainer to your battery, plug it in, and it will keep your battery at full charge while running the electronics, provided you have a maintainer with enough capacity. I would assume you would not need more than about 10 amps, so it would not take a very large unit to accomplish this task. Roger ________________________________________________________________________________
Date: Feb 14, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Z-13 question
At 12:51 PM 2/13/2010, you wrote: > >I have an all-electric airplane and am using Z-13 with a 40a stby alt. 40A standby alternator? How big is your main alternator and how are you mounting a driving a 40A standby machine? How have you integrated a 40A alternator into Z-13? At one time, there was a Z-13/20 that proved not to be an elegant recipe for success and it was withdrawn. > All mandatory engine power (EFI, IGN, etc) is on the battery bus How much current do each of your battery-bus accessories draw? >As I understand Z-13, if the battery has a short , it takes down the >battery bus, the redundant alternators notwithstanding, as there is >no disconnect from the battery/batt bus. It seems that putting a >DPST ON-ON switch between Batt Bus and Batt position & Alt 2 >position would allow one to isolate a problematic battery and supply >Alt 2 power to the Batt Bus and keeping the prop going round. > >I recognize that this defeats the bonehead-proof design of a hot >battery bus, but adds an option should there be a battery problem. >I'm not sure if it's a benefit or not. The probability of the 'problem' you are hypothesizing is vanishingly small especially if you worry as strongly about maintaining the battery as you seem to worry about it failing. In the TC aviation community, for high performance airplanes, it is common to pull a battery from service at about 80% capacity . . . it is still quite capable of starting engines but no longer meets design goals for emergency power. Cells shorted with some regularity in the old flooded batteries but only after they were no longer suitable for flight. >I would wire the two switch poles together to the batt buss, both >sides of position one to the battery, both sides of position 2 to >Alt 2. I think I'm buying some switch redundancy with a DPST. Before we address details of hardware, let's examine details of architecture and load analysis. I'm not sure we have a clear picture of what your proposed system looks like. Bob . . . ________________________________________________________________________________
Date: Feb 14, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: GPU for Piper
At 07:12 AM 2/14/2010, you wrote: >Roger, > >Yes, exactly. the G1000 has a ton of features, but they are only >useful if one knows how to find them. The mechanical part can be >read in the manual, but the reflexive part can only be learned >through arm-chair flying, so powering the panel is the objective. > >Your battery charger/minder idea is a good one, but I don't know how >much load can be shed to reduce amp draw. During normal operations, >it's pretty high at 67 amps, but that's with a bunch of accessories >and lights running. Perhaps the G1000 load will be <10 amp, but >something less than 20 amps is probably in a safe range. You would do well to first understand your electrical system's demands and deduce what level of control you have over those demands. The radio will be less than 10A in a 28v system. > >I want to be able to use the same power source for powering the >panel and then, setting it (or having it smart enough) to go to 1 >amp for trickle charging the battery longer term. I certainly don't >want to damage the battery by overcharging, since the replacement >cost implies that Piper has replaced the convention lead-acid >battery with a gold-acid battery. The device necessary to operate your systems on the ground is not a battery charger nor a battery maintainer. It's a power supply. You need to do a survey of energy requirements for accomplishing the proposed ground operations. This means get a hall effect ammeter . . . or install a temporary shunt in the battery lead. Bring the readout device into the cockpit and then start flipping switches/pulling breakers. See what configuration of breakers and controls gives you the desired functionality . . . and the measure the current necessary to meet that design goal. > >So, the task is to find a 110v input charger that will output 20 amp >24V for arm-chair flying but is smart enough to go to 1 amp long >term charging rate, the max recommended for the Concorde 38AH >battery, when used for battery charging or topping off. If your power supply emulates alternator performance then it would be set for 28.5 volts and it would also charge the battery. For ground ops, you don't want to burden a power supply tailored to the task with charging a battery also. Hence, you would set the power supply down to 25.0 volts. > >Are bigger versions of some of the battery minders discussed here >appropriate for the task? Apologies for asking others to do my >homework, but it's frustrating to know just enough about an issue to >have doubts. We had some discussions here on the list for crafting a professional grade ground power supply for supporting maintenance on both 14 and 28v airplanes. The elegant solution came in the form of an older, Hewlett-Packard robust bench supply on the order of 30 to 40 amps. This size device necessarily ran on 240 volts. But even a 40A supply would not support the ship's heaviest loads like air conditioners or transient loads like landing gear retraction systems. Having the battery 'floated' across the bus would support transient loads . . . but it's not enough snort to run large continuous loads. So the task before you is to define what list of goodies needs to be supported and then deduce how much current is required to support those items plus those over which you have no control. When you have that number, we can suggest sources for the hardware suited to your task. Bob . . . ________________________________________________________________________________
Subject: Re: Z-13 question
From: "jonlaury" <jonlaury(at)impulse.net>
Date: Feb 14, 2010
"How big is your main alternator and how are you mounting a driving a 40A standby machine? How have you integrated a 40A alternator into Z-13? At one time, there was a Z-13/20 that proved not to be an elegant recipe for success and it was withdrawn. " The main is 60A. The engine is a Franklin. When I installed EFI, the now vacant mechanical fuel pump pad provided a place to install a second alternator drive. The 40A ND alternator bolts thru it's mounting boss to the accessory case and the adjustment bracket the same. Re Z-13/20, we had a discussion about that and you recommended /8. I really didn't investigate /20 any further to see what differences there are from /8 and I assumed that the size of the stby alternator in /8 was irrelevant. "How much current do each of your battery-bus accessories draw? " EFI 5-8 amps (duty cycle dependent), EI (both) 7amps, Fuel pump (1 of 2) 3.5amps "The probability of the 'problem' you are hypothesizing is vanishingly small ...snip...after they were no longer suitable for flight." Point taken. Not worried about it any more. John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286392#286392 ________________________________________________________________________________
Date: Feb 14, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Z-13 question
>The main is 60A. The engine is a Franklin. When I installed EFI, the >now vacant mechanical fuel pump pad provided a place to install a >second alternator drive. The 40A ND alternator bolts thru it's >mounting boss to the accessory case and the adjustment bracket the same. > >Re Z-13/20, we had a discussion about that and you recommended /8. >I really didn't investigate /20 any further to see what differences >there are from /8 and I assumed that the size of the stby alternator >in /8 was irrelevant. > Is your standby alternator internally or externally regulated? Bob . . . ________________________________________________________________________________
Subject: Re: Z-13 question
From: "jonlaury" <jonlaury(at)impulse.net>
Date: Feb 14, 2010
> Is your standby alternator internally or externally >regulated? ER. Was IR. Out put is 20a @ 2000 shaft rpm, 30a @ 3200, 40a @ 5000. Engine alt drive @ 1.65 x eng rpm. John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286418#286418 ________________________________________________________________________________
Subject: Quote Function "How to" ?
From: "jonlaury" <jonlaury(at)impulse.net>
Date: Feb 14, 2010
Can someone explain how to use the "quote" function? I can't seem to get consistent results and didn't find anything in the Matronics FAQ or archives. Thanks John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286422#286422 ________________________________________________________________________________
Date: Feb 14, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Z-13 question
At 02:01 PM 2/14/2010, you wrote: > > > Is your standby alternator internally or externally > >regulated? > > >ER. Was IR. >Out put is 20a @ 2000 shaft rpm, 30a @ 3200, 40a @ 5000. Engine alt >drive @ 1.65 x eng rpm. Hmmmm . . . you may not quite see 40A from this alternator assuming red-line at 2700 . . . but it still seems quite adequate to the task. What's the expected loads on the battery bus? Bob . . . ________________________________________________________________________________
Subject: GPU for Piper
Date: Feb 14, 2010
From: "Chuck Jensen" <cjensen(at)dts9000.com>
Nuck/Roger/Bruce, Good ideas all. Bob suggested external power suggestion that sometimes it is connected through the battery and other times around the battery. In this case, the Meridian has external power plugged with the battery contactor open (off). For utility purposed, the battery start pack and a good high amp charger seems like it would serve my purposes and still have the utility of starting/charging the plane or other's plane. I like the idea of having the battery in the circuit as has been advised many times on this site, it's a world class capacitor and keeps a lot of things from bad endings when things don't go exactly right. I believe the minimum am load is about 12-13 amp, but the POH doesn't speak to it directly. I'm going to check with Piper to see if they see any shortcomings of this method. Hopefully, I can wrangle an answer out of them after they give me the spiel for the $3K charger. Chuck Jensen -----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: Sunday, February 14, 2010 9:49 AM Subject: RE: AeroElectric-List: GPU for Piper At 07:12 AM 2/14/2010, you wrote: Roger, Yes, exactly. the G1000 has a ton of features, but they are only useful if one knows how to find them. The mechanical part can be read in the manual, but the reflexive part can only be learned through arm-chair flying, so powering the panel is the objective. Your battery charger/minder idea is a good one, but I don't know how much load can be shed to reduce amp draw. During normal operations, it's pretty high at 67 amps, but that's with a bunch of accessories and lights running. Perhaps the G1000 load will be <10 amp, but something less than 20 amps is probably in a safe range. You would do well to first understand your electrical system's demands and deduce what level of control you have over those demands. The radio will be less than 10A in a 28v system. I want to be able to use the same power source for powering the panel and then, setting it (or having it smart enough) to go to 1 amp for trickle charging the battery longer term. I certainly don't want to damage the battery by overcharging, since the replacement cost implies that Piper has replaced the convention lead-acid battery with a gold-acid battery. The device necessary to operate your systems on the ground is not a battery charger nor a battery maintainer. It's a power supply. You need to do a survey of energy requirements for accomplishing the proposed ground operations. This means get a hall effect ammeter . . . or install a temporary shunt in the battery lead. Bring the readout device into the cockpit and then start flipping switches/pulling breakers. See what configuration of breakers and controls gives you the desired functionality . . . and the measure the current necessary to meet that design goal. So, the task is to find a 110v input charger that will output 20 amp 24V for arm-chair flying but is smart enough to go to 1 amp long term charging rate, the max recommended for the Concorde 38AH battery, when used for battery charging or topping off. If your power supply emulates alternator performance then it would be set for 28.5 volts and it would also charge the battery. For ground ops, you don't want to burden a power supply tailored to the task with charging a battery also. Hence, you would set the power supply down to 25.0 volts. Are bigger versions of some of the battery minders discussed here appropriate for the task? Apologies for asking others to do my homework, but it's frustrating to know just enough about an issue to have doubts. We had some discussions here on the list for crafting a professional grade ground power supply for supporting maintenance on both 14 and 28v airplanes. The elegant solution came in the form of an older, Hewlett-Packard robust bench supply on the order of 30 to 40 amps. This size device necessarily ran on 240 volts. But even a 40A supply would not support the ship's heaviest loads like air conditioners or transient loads like landing gear retraction systems. Having the battery 'floated' across the bus would support transient loads . . . but it's not enough snort to run large continuous loads. So the task before you is to define what list of goodies needs to be supported and then deduce how much current is required to support those items plus those over which you have no control. When you have that number, we can suggest sources for the hardware suited to your task. Bob . . . ________________________________________________________________________________
Subject: Re: Z-13 question
From: "jonlaury" <jonlaury(at)impulse.net>
Date: Feb 14, 2010
"Hmmmm . . . you may not quite see 40A from this alternator assuming red-line at 2700 . . . but it still seems quite adequate to the task. What's the expected loads on the battery bus? " EFI 5-8 amps (duty cycle dependent), EI (both) 7amps, Fuel pump (1 of 2) 3.5amp, E-Bus alt feed 10 amps. So all up, less than 30 amps including transmit power and full duty cycle on the injectors. The standard pulley on the Franklin overdrives the alt by about 10% and I could change pulleys to get the alt shaft speed up more, but I think the 30 amps is plenty and I'd like to keep the stby alt speed as low as possible for bearing life. 30 amps happens at about 1940 eng rpm so at normal power settings, there would be more than 30amps available. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286506#286506 ________________________________________________________________________________
Date: Feb 09, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Starter engaged light
At 08:41 AM 2/9/2010, you wrote: >Bob, >I was concerned when I read this post, as my OV/LV Sensor is just >the opposite. >The documentation that was provided from B&C states that "A flashing >light indicates a bus voltage greater than 15.5 volts DC, ; Steady >light indicates bus voltage below 12.5 volts DC." >That is how mine operates. Just trying to keep the confusion to a minimum. >Thanks for all you do. Oh . . . THAT OV/LV sensor. Yeah, I designed that one too. We needed to achieve dual functionality of a single indicator hence flashing vs. steady light. But just the same, the light should be illuminated before you bring the alternator on line . . . and go out when the bus voltage rises supported by alternator output. That product was designed for ultra-lights that generally have small alternators and no ov protection. If your system DOES have OV protection, should will probably never see a flashing light. The OV event should detected and shut down so fast that by the time you see the light, it will be steady indicating a LV condition. In any case, the light DOES things during startup that meets the "pre flight testable" design philosophy without providing a separate PTT feature. Bob . . . ________________________________________________________________________________
Date: Feb 15, 2010
From: John Markey <markeypilot(at)yahoo.com>
Subject: Re: G1000 on Ground Power
The Civil Air Patrol flies a fleet of 182T's with the G1000 panel. We have the ability to isolate every device to OFF while using the G1000 via a custom AUX switch for the Garmin suite. - The planes have a ground power receptacle built in, to which we would attach a regular 10 amp battery charger. This works well via an adapter with regular battery clamps - i.e., clamp-to-clamp. You can built a more elegant rigging, I am sure. ------ See Garmin current specs, attached below. We could upgrade/update the gps data set, train on the G1000 and even look at current weather to validate our flight plan for Go / No Go decision making. This is a great luxury to be able to sit on the ground and accomplish all these tasks without turning over the engine. Bob stated that he doesn't recommend this setup. Bob, would you elaborate on any issues that might results from this setup? Best regards, John Markey Deep peace of the Light of the World to you. -------- ------------------------- ---------------- --A Gaelic Blessing Garmin=0A G1000 / NAV III Solid State EFIS SystemFile =0AFormat: PDF/Adobe Acrobat - Quick=0A View PFD/MFD Combined Power Consumption. 2.5 A @ 28VDC.=0A 6.0 A @ 28VDC. MFD - Full Overlay Capability ... Garmin G1000=0A (Cessna). Avidyne Entegra (Cirr us) ... www.airplanenoise.com/docs/G1000Guide.pdf=0A - Similar =0A=0A=0A ________________________________________________________________________________
Date: Feb 16, 2010
Subject: Are home grown temperature probes feasable?
From: rparigor(at)suffolk.lib.ny.us
Not quite sure if I really want to fly my Europa or just keep finding projects to keep on adding to build time? AnywayI have a Ilec SC-7 variometer. It comes with a momentary switch to view temperature and comes with one sender. The sender is 3/16" diameter cylinder with a flat and 3/16" long.I forget exactly what the sender is called, but essentially it is a Zener diode. There is 3 legs of the sender but they cut off 1 leg and only use 2 legs. The third leg they cut offis for calibrating. You see since this was for gliders to measure outside air temperature they have a calibration inside unit.I figurecould calibrate several senders so they are the same then use a rotary switch to select different locations. Senders are about a buck each. I plan to use a rotary switch with gold contacts. OK so somehow I figure it would be nice to have OAT, temperature under panel by radios to see if my mini fans help, and 3 specific under cowl temperatures. ThenI got to thinking it would be nice to monitor airbox temperature on my 914 turbocharged Rotax with intercooler to make sure there are not any sour spots during operation that could be conducive carb ice like high airspeed, fine pitch and very low throttle setting, and even though I plan to start with Evans as a coolant, might as well increase the build time somemore and have ability to monitor coolant temperature. What I proposeto make is an airbox probe that would begin life with a slug of hex stock brass, then machineh NPT thread to screw in an aux hole in existing airbox, make a .045" wall blind hole in center bout 1.5" long with a .1875" ID (3/16"). BTW close to dimensions of UMA sender they sell except 1/2" longer. I would insert temperature sender then fill with high temperature JB Weld.I figure that the thin wall tube would not conduct too much heat to the airbox, yet the tip would have sufficient contact area with sender to conduct airbox temperature to it. Similar probe for water temperature. Thoughts on feasability? Or not only is there something that will not work well, butI am going to send a nice chunk of brass and semiconductor through a hot running motor because the coolant sender breached and leaked out all my flamable coolant directing it right onto the hot exhaust, probably precisely towardsthe beyond red hot turbo housing of the turbo? All comments welcome. Thx. Ron Parigoris ________________________________________________________________________________
Subject: Re: Are home grown temperature probes feasable?
From: "rampil" <ira.rampil(at)gmail.com>
Date: Feb 16, 2010
Hi Ron, Now come on, we all know you want to keep building ;-) Dump that Evans coolant for real water! Yes, you can make all the TC sensors you want with a small spot welder. Performance will be highly variable until you can make the welds perfectly uniform (for the metal-metal interface). The best choice in your situation is to use ic temp sensors which are factory calibrated and voltage compensated and run into a factory built temp gauge. These sensors put out 0-5 volt so there are no issues about microvolt voltage drops on dirty rotary switch contacts. -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286640#286640 ________________________________________________________________________________
Subject: Re: Are home grown temperature probes feasable?
From: "rparigoris" <rparigor(at)suffolk.lib.ny.us>
Date: Feb 16, 2010
Hi Ira The sender I want to use is I think the IC you describe, not make my own thermocouple (have done that though with great success, see below). JB Weld is a two part epoxy you can get from Aviation Isle at Home Depot or most Hardware stores. TG from memory is like 550F and it is probably as immune to fuel/alcohol as is Redux, just with a much higher TG. I want to use the JB Weld Epoxy to mount my IC sender to the tip of my turned brass blind holed hex. JB also makes a product called JB KWIK and it is called 4 minute epoxy. TG perhaps is 350F going by memory and strength is down perhaps 15% from JB Weld that has an 8 hour cure time. It is probably fine for what I need in probe as far as strength and TG, but it is far more viscous compared to JB Weld. If you warm JB Weld it gets plenty runny to get it where I want it. JB KWIK has been invaluable in build thus far. BTW I have repaired many a thermocouple with using my Hobart TRT 250 round wave TIG welder! My business is copiers and older machines used thermocouples that were two dissimilar wires welded together where the tip was pretty spherical. Anyway they were close to 8" long and the tips would get brittle and a paper jam could break them. I used to cut off an inch, jig together and go after with my TIG torch. If a nice spherical ball happened it was then was good to go again. If the ball was not nice just redid it till it was nice. I measured against a new one and if ball was close to what i call nice (using my Mk 1 calibrated "Eyechrometer") it was dead on compared to new unit. Used same technique for other thermocouples, and where I needed longer wire just bought same material and made a new one in desired length. > Now come on, we all know you want to keep building ;-) The best choice in your situation is to use ic temp sensors which are factory calibrated and voltage compensated and run into a factory built temp gauge. These sensors put out 0-5 volt so there are no issues about microvolt voltage drops on dirty rotary switch contacts.< I am pretty certain this is the sender that Ilec uses to drive their digital readout, it is just a Zener diode. It has 3 wires and one allows you to calibrate, or in my case match 6 of them. I imagine that someone selling a sender could precalibrate it for their gauge, but Ilec cuts off third leg and allows for internal calibration in their unit. I will buy for a buck each and match calibrations for 6 senders, then calibrate Ilec to the now same values. Using a rotary switch with gold contacts for such a flea sized amount of electrons flowing through contacts, I am hopeful it will not cause problems of switching thermocoulpe wires. Ron Parigoris Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286651#286651 ________________________________________________________________________________
Subject: Re: Are home grown temperature probes feasable?
From: "rampil" <ira.rampil(at)gmail.com>
Date: Feb 16, 2010
Dont waste your time dinking with zeners! Nice for an experiment to demonstrate principles but insane for production use. Especially in your case where you want several, all needing to be matched! As I suggested for OAT, use a temp chip like for example: http://www.analog.com/en/temperature-sensing-and-thermal-management/analog-temperature-sensors/tmp36/products/product.html It's $0.45 in quantity! why would you even think about zeners. Jim's spent too much time in the classroom teaching EE techs. Feasible yes, best choice? not a chance. PS I have 13 temp probes on my Europa -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286653#286653 ________________________________________________________________________________
Subject: Re: Are home grown temperature probes feasable?
From: "rparigoris" <rparigor(at)suffolk.lib.ny.us>
Date: Feb 16, 2010
Hi Ira Wayne explained to me the devise I speak of operates or is based on a Zener, I am not exactly sure which one. It is not just an ordinary Zener but a a precision mapped thermal temperature sender and sold as such with accuracy in mapping from one to the other of perhaps 2 or 3 degrees F, and by using the trim feature you can adjust a lot closer than that. I apreciate your advise about not using a Zener. The reason for selecting this specific device is that is what the Mfg of the Ilec SC-7 vario uses to drive their thermal display. Would you mind listing the 13 locations you have placed sensors and comment if they would be worthy of installing if you were to do it again. Thx. Ron Parigoris Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286670#286670 ________________________________________________________________________________
Date: Feb 16, 2010
Subject: Re: Are home grown temperature probes feasable?
From: rparigor(at)suffolk.lib.ny.us
Hi Ira The senderI want to use is I think the IC you describe, not make my own thermocouple (have done that though with great sucess, see below). JB Weld is a two part epoxy you can get from Aviation Isle at Home Depot or most Hardware stores.TG from memory is like 550F and it is probably as immune to fuel/alcohol as is Redux, just with a much higher TG. I want to use the JB Weld Epoxy to mount my IC sender to the tip of my turned brass blind holed hex. JB also makes a product called JB KWIK and it is called 4 minute epoxy. TG perhaps is 350F going by memory and strength is down perhaps 15% from JB Weld that has an 8 hour cure time. It is probably fine for what I need in probe as far as strength and TG, but it is far more viscous compared to JB Weld. If you warm JB Weld it gets plenty runny to get it where I want it. JB KWIK has been invaluable in build thus far. BTW I have repaired many a thermocouple with using my Hobart TRT 250 round wave TIG welder! My business is copiers and older machines used thermocouples that were two dissimilar wires welded together where the tip was pretty spherical. Anyway they were close to 8" long and the tips would get brittle and a paper jam could break them. I used to cut off an inch, jig together and go after with my TIG torch. If a nice spherical ball happenedit was thenwas good to go again. If the ball was not nice just redid it till it was nice. I measured against a new one and if ball was close to what i call nice (using my Mk 1 calibrated "Eyechrometer") it was dead on compared to new unit. Used same technique for other thermocouples, and where I needed longer wire just bought same material and made a new one in desired length.> Now come on, we all know you want to keep building ;-) < You have my number now don't you! > Dump that Evans coolant for real water!< If my plans to keep engine kool don't quite work out, I may just do that and install a higher pressure cap and can monitor water temp with described probe. >The best choice in your situation is to use ic temp sensors which are factory calibrated and voltage compensated and run into a factory built temp gauge. These sensors put out 0-5 volt so there are no issuesabout microvolt voltage drops on dirty rotary switch contacts.< I am pretty certain this is the sender that Ilec uses to drive their digital readout, it is just a Zener diode. It has 3 wires and one allows you to calibrate, or in my case match 6 of them. I imagine that someone selling a sender could precalibrate it for their gauge, but Ilec cuts off third leg and allows for internal calibration in their unit.I will buy for a buck each and match calibrations for 6 senders, then calibrate Ilec to the now same values. Using a rotary switch with gold contacts for such a flea sizedamount of electrons flowing through contacts, I am hopeful it will not cause problems of switching thermocoulpe wires. Ron Parigoris ________________________________________________________________________________
Date: Feb 16, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: re: Are home grown temperature probes feasible?
At 11:17 AM 2/16/2010, you wrote: Dont waste your time dinking with zeners! Nice for an experiment to demonstrate principles but insane for production use. Especially in your case where you want several, all needing to be matched! As I suggested for OAT, use a temp chip like for example: http://www.analog.com/en/temperature-sensing-and-thermal-management/analog-temperature-sensors/tmp36/products/product.html It's $0.45 in quantity! why would you even think about zeners. Jim's spent too much time in the classroom teaching EE techs. Feasible yes, best choice? not a chance. ================================== Good lick! You beat me to it Ira. There is indeed a whole class of out-of-the-box, calibrated, easy to use temperature sensors. They tend to behave like a zener with a calibrated temperature coefficient . . . but are indeed rather complex integrated circuits. One such device suited to the task is: Part Listing: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=497-7324-5-ND Datasheet: http://www.st.com/stonline/books/pdf/docs/2158.pdf I've used the big brothers to this device in dozens of applications over the years. Here's one recipe for success in wiring, packaging and mounting this and similar devices: http://aeroelectric.com/Pictures/Instruments/Temperature/LM135_Temp_Sensor/ I've mostly used the super-spec devices like the LM135 . . . but for our purposes the lower cost, less accurate devices will suffice. The rudimentary wiring diagram illustrates the manner in which we used these devices to feed directly into a data acquisition system . . . http://aeroelectric.com/Pictures/Data_Acquisition/Weeder_Module_DAS_2.jpg monitored by an ordinary lap-top to record a multitude of phenomenon including temperatures. These sensors have been potted into heat sinks, 8AWG terminals for surface mounting, drilled into the heads of bolts, glued to surfaces (E-6000 or J-B Weld works good), etc. Many applications simply hung the device in the open air for an ambient measurement. If you want a direct reading, degrees C or even degrees F display, there are low cost, LCD displays (the last picture) with a 200mV full scale basic sensitivity. With the addition of a few 1% resistors, perhaps a couple of pots, and a precision voltage reference, you can re-scale and offset the reading to display degrees C directly. But by simply scaling the device for 20 volts full scale (100:1 divider) the device will read out in degrees K. A K-degree is the same size as a C-degree, 273K is freezing. The simpler display isn't too hard to learn to use. Room temp is 300K, boiling is 373K. This approach is good for about +/- 2 degrees C accuracy without going to more sophisticated components, wiring and bench calibration. The DAS system illustrated was supported by a PC based utility that permitted scaling and offset adjustment to get about 0.5 degree C accuracy. Bob . . . ________________________________________________________________________________
Subject: Re: Are home grown temperature probes feasible?
From: "rampil" <ira.rampil(at)gmail.com>
Date: Feb 16, 2010
Exactly Bob! I could not have said it better myself! Lets not forget that zeners have a non-linear response to temp, whereas the chips are exactly linear (to within reason :)) with a response of something like 10 mV per degree from bottom to top. Try building an analog device to replicate an arbitrary log response! -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286696#286696 ________________________________________________________________________________
Subject: Re: Are home grown temperature probes feasable?
From: "rampil" <ira.rampil(at)gmail.com>
Date: Feb 16, 2010
OK Ron, Actually, it's 15 probes (forgot Oil ;-) and internal BMA avionics temp) 4 CHT on ring probes 2 CHT on Rotax probes 4 EGT t/c 1 OAT 1 Coolant temp 1 Carb heater block 1 Oil temp 1 Blue Mountain avionics overtemp sensor (display starts at 135F) All except two Rotax probes go to EFIS 2 system for display. All calibrated by factory and tested by me. OAT in lower cowl is unreliable read due to radiated engine heat Ira -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286697#286697 ________________________________________________________________________________
Date: Feb 16, 2010
From: D <dfritzj(at)yahoo.com>
Subject: Re: GPU for Piper
I've been using a pair of 7Ahr AGM batteries for ground power for my 28V system. They can be had at any of the on-line battery houses for about $20 and are easy to maintain. Works like a charm. Dan ________________________________________________________________________________
Date: Feb 16, 2010
From: "J. Mcculley" <mcculleyja(at)starpower.net>
Subject: Re: Are home grown temperature probes feasable?
Ron, I'm operating a very inexpensive, minimum labor system I put together to monitor 18 under-cowl temperatures during some 500 hours of flight operation over the past 7 years. The cost was less than about $25 and the accuracy is +/- 2 degrees F for temperatures less than 300F. Nothing under the cowl aside from CHT and EGT should ever be higher than that! Contact me directly if you want more detail. Jim McCulley mcculleyja(at)starpower.net ============================================================================== rparigor(at)suffolk.lib.ny.us wrote: > Not quite sure if I really want to fly my Europa or just keep finding > projects to keep on adding to build time? > Anyway I have a Ilec SC-7 variometer. It comes with a momentary switch > to view temperature and comes with one sender. The sender is 3/16" > diameter cylinder with a flat and 3/16" long. I forget exactly what the > sender is called, but essentially it is a Zener diode. There is 3 legs > of the sender but they cut off 1 leg and only use 2 legs. The third leg > they cut off is for calibrating. You see since this was for gliders to > measure outside air temperature they have a calibration inside unit. I > figure could calibrate several senders so they are the same then use a > rotary switch to select different locations. Senders are about a buck > each. I plan to use a rotary switch with gold contacts. OK so somehow I > figure it would be nice to have OAT, temperature under panel by radios > to see if my mini fans help, and 3 specific under cowl temperatures. > Then I got to thinking it would be nice to monitor airbox temperature on > my 914 turbocharged Rotax with intercooler to make sure there are not > any sour spots during operation that could be conducive carb ice like > high airspeed, fine pitch and very low throttle setting, and even though > I plan to start with Evans as a coolant, might as well increase the > build time somemore and have ability to monitor coolant temperature. > What I propose to make is an airbox probe that would begin life with a > slug of hex stock brass, then machineh NPT thread to screw in an aux > hole in existing airbox, make a .045" wall blind hole in center bout > 1.5" long with a .1875" ID (3/16"). BTW close to dimensions of UMA > sender they sell except 1/2" longer. I would insert temperature sender > then fill with high temperature JB Weld. I figure that the thin wall > tube would not conduct too much heat to the airbox, yet the tip would > have sufficient contact area with sender to conduct airbox temperature > to it. Similar probe for water temperature. Thoughts on feasability? Or > not only is there something that will not work well, but I am going to > send a nice chunk of brass and semiconductor through a hot running motor > because the coolant sender breached and leaked out all my flamable > coolant directing it right onto the hot exhaust, probably precisely > towards the beyond red hot turbo housing of the turbo? > All comments welcome. > Thx. > Ron Parigoris ================================================================================== ________________________________________________________________________________
Date: Feb 16, 2010
Subject: Re: re: Are home grown temperature probes feasible?
From: rparigor(at)suffolk.lib.ny.us
Hi Bob and Ira I am not at the hangar at the moment but took a look at data sheet: http://www.st.com/stonline/books/pdf/docs/2158.pdf TO-92 looks like what Ilec is using, you can see the adjustment on the datasheet I speak about, thus can match all senders so they are equal, then i can adjust my Ilec to read correctly from any sender. We are all on the same page. Imay have confused speaking how Ilec does things, since they are only meant for 1 sender, they do hocus pocus in their unit to adjust andcompensate for any tolerance error on senders part. In my case forcing the unit that is already installed to read correctly off of multiple senders, i will just adjust all senders to be equal, then adjust unit. Ron Parigoris ________________________________________________________________________________
Date: Feb 16, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Temperature Probes
At 04:14 PM 2/16/2010, you wrote: >Hi Bob and Ira >I am not at the hangar at the moment but took a look at data sheet: ><http://www.st.com/stonline/books/pdf/docs/2158.pdf>http://www.st.com/stonline/books/pdf/docs/2158.pdf >TO-92 looks like what Ilec is using, you can see the adjustment on >the datasheet I speak about, thus can match all senders so they are >equal, then i can adjust my Ilec to read correctly from any sender. Yeah . . . that's the LM135 series devices I was talking about. They have an initial accuracy of 1C or about 2F. Doing the 'adjustment' means adding components at the temperature sensor location or bringing the third wire back to the instrumentation package. Consider carefully if you need better accuracy and how hard you're willing to work to achieve it. > We are all on the same page. I may have confused speaking how > Ilec does things, since they are only meant for 1 sender, they do > hocus pocus in their unit to adjust and compensate for any > tolerance error on senders part. Yup, that's the offset and scale factor constants that I mentioned for the software that reads my DAS . . . > In my case forcing the unit that is already installed to read > correctly off of multiple senders, i will just adjust all senders > to be equal, then adjust unit. That will get your offset covered but see how close they are without fiddling. If you need tighter accuracy, then it might be worthwhile to consider the LM135Z with an out of the box initial accuracy of 0.5C or about 1F. Even off the spool thermocouple wire is only +/- 2C stuff. The thermocouple signal conditioners add another couple degrees uncertainty. I can't ever recall a situation where we needed more temperature accuracy than the unadjusted products offered. Bob . . . ________________________________________________________________________________
Subject: Z-12 SD-20 wire size / fusible link size
From: "N601RT" <N601RT(at)comcast.net>
Date: Feb 16, 2010
Bob, (Rev 12A) Z-12 suggests using a 10 gauge wire for the B-lead from the SD-20 with a 16 gauge fusible link. I believe you recommend sizing fusible links with wire that is 4 sizes smaller than the wire being protected. I'm guessing the B-lead wire size was changed during a cut-&-paste from 12 gauge to 10 gauge without re-sizing the fusible link? Do you recommend 10 gauge wire for an SD-20 B-lead and if so do you recommend 14 gauge wire for a fusible link if a fusible link is used to protect the B-lead? Regards, Roy N601RT: 2003 CH601HDS, nose gear, Rotax 912ULS, All electric, IFR equipped, 1340hrs Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286761#286761 ________________________________________________________________________________
Date: Feb 17, 2010
Subject: Re: Are home grown temperature probes feasable?
From: rparigor(at)suffolk.lib.ny.us
Hi Ira Thx for the info on your 15 probes. Curious, you mention you have 4 CHT ring probes that I think are the type that get sandwiched between spark plug and cylinder head. Why did you go that route as compared to purchasing two extra CHT probes from Rotax which would allow reading all 4 cylinders? Perhaps it gives you a more desirable reading? Or?? Thx. Ron Parigoris ________________________________________________________________________________
Date: Feb 17, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Z-12 SD-20 wire size / fusible link size
At 12:44 AM 2/17/2010, you wrote: > >Bob, > >(Rev 12A) Z-12 suggests using a 10 gauge wire for the B-lead from >the SD-20 with a 16 gauge fusible link. I believe you recommend >sizing fusible links with wire that is 4 sizes smaller than the wire >being protected. I'm guessing the B-lead wire size was changed >during a cut-&-paste from 12 gauge to 10 gauge without re-sizing the >fusible link? Do you recommend 10 gauge wire for an SD-20 B-lead and >if so do you recommend 14 gauge wire for a fusible link if a fusible >link is used to protect the B-lead? 16AWG would be fine . . . so would 14AWG . . . it just needs to serve the function of "electrically weak link" while not overheating beyond that which the insulation will stand . . . 16AWG isn't even close to getting too hot at 20A. See: http://aeroelectric.com/Pictures/Wire/22AWG_20A.pdf I'm working on tooling to build a base for the minature ANL style current limiters. We'll be offering these "robust fuses" on the website in the not too distant future. That "4AWG downsize" rule is a minimum step size, it COULD be 6 or even 8AWG smaller in some cases. For a 20A alternator, 12AWG b-lead with a 16AWG fusible link would be centered on contemporary design goals. Bob . . . ________________________________________________________________________________
Subject: Re: Basic Electricity....Grrrrr.........
From: "XeVision" <dblumel(at)XeVision.com>
Date: Feb 17, 2010
We encounter an even more basic issue on occasion regarding 12 or 24Volts availability at the ballast. Once in a while, we get the call "I have 12 volts at the ballast input connector but the light does not come on when I hook power to it". My response is typically, try measuring the voltage at that location with a load on it. Either our system, a light bulb (incandescent) or other load. Do you still have about 12V or 24V with the load or does the voltage plummet as soon as a load is applied. If so, look for corroded connections in the wiring, a bad switch, a bad ground, etc. Sometimes they are using the airframe for ground (not our preference) and sometimes the airframe at that location is not well grounded back to the neg bus/ neg bat terminal. People building airplanes, if they do any of the electrical work, should learn some basics of how electrical circuits work. When they don't understand these basics they automatically blame the non operational component(s). -------- 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=286865#286865 ________________________________________________________________________________
Subject: Re: Are home grown temperature probes feasable?
From: "rampil" <ira.rampil(at)gmail.com>
Date: Feb 17, 2010
nope, the reason was BMA compatibility -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286870#286870 ________________________________________________________________________________
Date: Feb 17, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: S701 Contactor Failure Analysis
Last year, Marty Emrath told us about the failure of a new contactor he had purchased from B&C. B&C replaced the contactor but Marty was justifiably curious as to root cause of the failure. I offered to document a tear-down analysis and Marty sent me the carcass. I was looking for something fun to do this afternoon so I took the dead puppy apart. The pictures at . . . http://www.aeroelectric.com/Pictures/Contactors/S701_Failure_Teardown/ Are pretty much self explanatory. One thing is for certain. This product is much more sophisticated than its ancestors that first took to the air in a C-140. The last picture tells the tale . . . http://www.aeroelectric.com/Pictures/Contactors/S701_Failure_Teardown/TearDown_10.jpg Seems the assembler wasn't really awake yet when this device went across their work station. One coil wire was poorly soldered to its terminal . . . the other had no solder at all. Thanks for sharing your experience with us Martin! Bob . . . ________________________________________________________________________________
Date: Feb 17, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: S701 Contactor Failure Analysis
> >The last picture tells the tale . . . > >http://www.aeroelectric.com/Pictures/Contactors/S701_Failure_Teardown/TearDown_10.jpg > >Seems the assembler wasn't really awake yet when this >device went across their work station. One coil wire >was poorly soldered to its terminal . . . the other had >no solder at all. Already had a comment on the analysis . . . someone noted that the terminals around which the coil wires are wrapped are square and may indeed have sharp corners. He reminded me of an arcane point-to-point wiring process for complex digital circuits called "wire wrap". This process used special wire, tools, sharp edged square terminal posts and no solder. The tools were designed to tightly wrap the wire around the post with enough turns, and stretching force to create multiple gas-tight joints on the corners at each connection. As I recall this technology called for about 6 tightly spaced turns around the post (24+ points of contact). Since this coil-form is plastic . . . and soldering these joints would call for considerable heat and time, it may well be that the original design calls for no solder at all. In this case, the assembler of the failed item was perhaps not in possession of the right tool. The turns about both posts are not those produced by a "wire wrap" tool. The curious thing is that there is SOME solder on one of the terminals . . . perhaps didn't pass a continuity test and the solder dab "fixed it" only to have the other joint fail later. Guess we'll have to tear down another contactor to see. I don't think I have one in the shop. I'll go buy one. Bob . . . ________________________________________________________________________________
Date: Feb 17, 2010
From: Ron Quillin <rjquillin(at)cox.net>
Subject: Re: S701 Contactor Failure Analysis
You have a good recollection. I just did some wire-wrap late last year. However, the wire used has Kynar or other insulation that is removed to expose a bare, generally tin coated, conductor. The wire used to wind the coil, from your pictures, appears to be 'magnet' wire which has an insulating coating. The wire-wrap process, as I have always seen it implemented, is not designed for this type of insulated wire and is not expected to breech the insulation to form a contact. I believe your original diagnosis of no solder was spot-on. Ron Q. At 18:18 2/17/2010, you wrote: >He reminded me of an arcane point-to-point wiring process > for complex digital circuits called "wire wrap". This > process used special wire, tools, sharp edged square terminal > posts and no solder. The tools were designed to tightly > wrap the wire around the post with enough turns, and > stretching force to create multiple gas-tight joints > on the corners at each connection. > > As I recall this technology called for about 6 tightly > spaced turns around the post (24+ points of contact). > Since this coil-form is plastic . . . and soldering these > joints would call for considerable heat and time, > it may well be that the original design calls for > no solder at all. ________________________________________________________________________________
From: "Bret Smith" <smithhb(at)tds.net>
Subject: S701 Contactor Failure Analysis
Date: Feb 17, 2010
Thank you Bob, It is always interesting to learn more about the art of aircraft electronics. Bret Smith RV-9A N16BL Blue Ridge, GA www.FlightInnovations.com -----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: Wednesday, February 17, 2010 9:18 PM Subject: Re: AeroElectric-List: S701 Contactor Failure Analysis > >The last picture tells the tale . . . > >http://www.aeroelectric.com/Pictures/Contactors/S701_Failure_Teardown/TearD own_10.jpg > >Seems the assembler wasn't really awake yet when this >device went across their work station. One coil wire >was poorly soldered to its terminal . . . the other had >no solder at all. Already had a comment on the analysis . . . someone noted that the terminals around which the coil wires are wrapped are square and may indeed have sharp corners. He reminded me of an arcane point-to-point wiring process for complex digital circuits called "wire wrap". This process used special wire, tools, sharp edged square terminal posts and no solder. The tools were designed to tightly wrap the wire around the post with enough turns, and stretching force to create multiple gas-tight joints on the corners at each connection. As I recall this technology called for about 6 tightly spaced turns around the post (24+ points of contact). Since this coil-form is plastic . . . and soldering these joints would call for considerable heat and time, it may well be that the original design calls for no solder at all. In this case, the assembler of the failed item was perhaps not in possession of the right tool. The turns about both posts are not those produced by a "wire wrap" tool. The curious thing is that there is SOME solder on one of the terminals . . . perhaps didn't pass a continuity test and the solder dab "fixed it" only to have the other joint fail later. Guess we'll have to tear down another contactor to see. I don't think I have one in the shop. I'll go buy one. Bob . . . ________________________________________________________________________________
Date: Feb 17, 2010
From: "Richard E. Tasker" <retasker(at)optonline.net>
Subject: Re: S701 Contactor Failure Analysis
Your recollection is generally true and the same as the wire I have used for all the wire wrapping I have done. However, once upon a time there was wire sold for wrapping that did not require stripping. Unfortunately, I don't remember who sold it nor do I have any. Further, I seem to recall that it was not too successful as it eventually tended to short anywhere it overlapped under tension. The wire on the teardown certainly looks like common magnet wire. And in any case, three or four turns would certainly not be sufficient to make long term reliable contact in something like this which is likely to be exposed to rather harsh environmental conditions. I agree with Bob that they just forgot to solder the wires - the operator probably got interrupted during assembly. Dick Tasker Ron Quillin wrote: > You have a good recollection. > > I just did some wire-wrap late last year. > However, the wire used has Kynar or other insulation that is removed > to expose a bare, generally tin coated, conductor. > > The wire used to wind the coil, from your pictures, appears to be > 'magnet' wire which has an insulating coating. The wire-wrap process, > as I have always seen it implemented, is not designed for this type of > insulated wire and is not expected to breech the insulation to form a > contact. > > I believe your original diagnosis of no solder was spot-on. > > Ron Q. > > At 18:18 2/17/2010, you wrote: >> He reminded me of an arcane point-to-point wiring process >> for complex digital circuits called "wire wrap". This >> process used special wire, tools, sharp edged square terminal >> posts and no solder. The tools were designed to tightly >> wrap the wire around the post with enough turns, and >> stretching force to create multiple gas-tight joints >> on the corners at each connection. >> >> As I recall this technology called for about 6 tightly >> spaced turns around the post (24+ points of contact). >> Since this coil-form is plastic . . . and soldering these >> joints would call for considerable heat and time, >> it may well be that the original design calls for >> no solder at all. > * > > > * -- 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. -- ________________________________________________________________________________
Date: Feb 17, 2010
From: "Bill Watson" <mauledriver(at)nc.rr.com>
Subject: Re: S701 Contactor Failure Analysis
I'm feeling old... My only hands-on experimental circuit making was pre-dig ital. =C2- Over the years I'd pickup electronics mags and see references to "wire wrapped" terminals and never had a clue what it referred to. =C2 -Now I get it... Thanks. Bill -- Sent from my Palm Pre Ron Quillin wrote: You have a good recollection. I just did some wire-wrap late last year. However, the wire used has Kynar or other insulation that is removed to expose a bare, generally tin coated, conductor. The wire used to wind the coil, from your pictures, appears to be 'magnet' wire which has an insulating coating.=C2- The wire-wrap process, as I have always seen it implemented, is not designed for this type of insulated wire and is not expected to breech the insulation to form a contact. I believe your original diagnosis of no solder was spot-on. Ron Q. At 18:18 2/17/2010, you wrote: He reminded me of an arcane point-to-point wiring process =C2- for complex digital circuits called "wire wrap". This =C2- process used special wire, tools, sharp edged square terminal =C2- posts and no solder. The tools were designed to tightly =C2- wrap the wire around the post with enough turns, and =C2- stretching force to create multiple gas-tight joints =C2- on the corners at each connection. =C2- As I recall this technology called for about 6 tightly =C2- spaced turns around the post (24+ points of contact). =C2- Since this coil-form is plastic . . . and soldering these =C2- joints would call for considerable heat and time, =C2- it may well be that the original design calls for =C2- no solder at all. ________________________________________________________________________________
Date: Feb 17, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: S701 Contactor Failure Analysis
At 10:22 PM 2/17/2010, you wrote: >I'm feeling old... My only hands-on experimental >circuit making was pre-digital. Over the >years I'd pickup electronics mags and see >references to "wire wrapped" terminals and never >had a clue what it referred to. Now I get it... Thanks. > >Bill see: http://en.wikipedia.org/wiki/Wire_wrap This is the modern incarnation used on complex backplanes where gazillion-layer boards are impractical. The no-strip version is from way-back-when and it didn't hang around long. Bob . . . ________________________________________________________________________________
Date: Feb 17, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: S701 Contactor Failure Analysis
>The wire on the teardown certainly looks like common magnet >wire. And in any case, three or four turns would certainly not be >sufficient to make long term reliable contact in something like this >which is likely to be exposed to rather harsh environmental >conditions. I agree with Bob that they just forgot to solder the >wires - the operator probably got interrupted during assembly. Just for grins, I took a chunk of the wire off the failed coil and subjected it to a puddle of molten solder. The insulation was indeed a "solder-eze" type . . . you can solder through it without pre- stripping. The plastic used on the bobbin did melt at soldering iron temperatures but not quickly. So it seems a rational deduction that the failed joints were intended to be soldered. The right temperature and flux combination would have produced a reliable joint with minimal effect on the bobbin. I guess I won't go buy one to take apart . . . perhaps we'll get another carcass to inspect for other reasons one day. Bob . . . ________________________________________________________________________________
Subject: Re: S701 Contactor Failure Analysis
From: "tomcostanza" <Tom(at)CostanzaAndAssociates.com>
Date: Feb 18, 2010
If I remember correctly, the wire-wrap technique was only for microamp level circuits; a few milliamps at the most. I never saw any wire-wraps for the approx 1 amp that the contactor would need. Or am I mistaken? Clear Skies, Tom -------- Clear Skies, Tom Costanza Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286910#286910 ________________________________________________________________________________
From: "LINDA WALKER" <l.p(at)talk21.com>
Subject: Re: BMA Efis G4 Lite
Date: Feb 18, 2010
Help! The backlight yesterday went on my Blue Mountain Avionics EFIS G4 Lite! Possibly, and hopefully, this is an inverter issue, and not the display itself. As this company no longer exists, can anyone suggest the best method for getting this sort of problem rectified? Are the circuit board schematics for their products available anywhere? Any help much appreciated. Patrick Elliott, Reigate, Surrey, England. Long-Ez, G-LGEZ. ----- Original Message ----- From: "AeroElectric-List Digest Server" <aeroelectric-list(at)matronics.com> Sent: Thursday, February 18, 2010 7:55 AM Subject: AeroElectric-List Digest: 12 Msgs - 02/17/10 ________________________________________________________________________________
Subject: Re: BMA Efis G4 Lite
From: "n395v" <Bearcat(at)bearcataviation.com>
Date: Feb 18, 2010
Best to go to the BMA website or www.vansairforce.net and advertise for G4 lite wanted. Or watch e bay. One or 2 sold recently for less than$500. -------- Milt Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286915#286915 ________________________________________________________________________________
Date: Feb 17, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: For you workers in wood
I've been acquiring some new skills in my Dad's refurbished shop. I've been building shelves and benches for the new digs and cabinets for the house in Lindsborg KS where Dr. Dee teaches. I've owned several sets of dado blades and was reasonably satisfied with their work product until this week . . . One of the M.L. locals is a cabinet builder who knew my dad. He stopped by about a week ago when he saw the garage door open. During our conversation he noted an old dado set I had laying on the table and remarked that I might like to try a Freud brand dado set. I read up on them and found a range of prices that were probably related to quality/capability. I sucked in a breath and ordered a 6" model 206 for about $80 (about 2x what I usually spent on dado sets). Got it in the mail last Monday and got a chance to try it today. What a tool! Very nicely crafted. very precise and wonderfully smooth-bottom grooves. Very little splintering of cross cuts on oak faced plywood. If anyone on the List has occasion to build shelves or fixtures that would benefit from tight, square joints in solid or plywood, I can report that the new blade-set is worth every dime I spent on it. I'm also working on a fixture that will allow dado cuts across lumber as wide as 24" on a relatively short table saw. I'll report on that when reasonably perfected. Bob . . . ________________________________________________________________________________
Date: Feb 18, 2010
From: Werner Schneider <glastar(at)gmx.net>
Subject: Re: BMA Efis G4 Lite
Or go and buy a Dynon Skyview and get 1000$ for your broken G4 <http://www.dynonavionics.com/docs/SkyView_BMA_Trade-In.html> Werner On 18.02.2010 14:28, n395v wrote: > --> AeroElectric-List message posted by: "n395v" > > Best to go to the BMA website or www.vansairforce.net and advertise for G4 lite wanted. Or watch e bay. One or 2 sold recently for less than$500. > > Also try calling Greg Richter- 404-434-3990 > > apparently sometimes he answers and may be able to tell you how to fix it. > > -------- > Milt > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=286915#286915 > > ________________________________________________________________________________
Subject: Re: BMA Efis G4 Lite
Date: Feb 18, 2010
From: <longg(at)pjm.com>
I agree, BMA - don't even go there. they haven't updated that product since the Clinton administration. So many people have had issues with their systems - why torture yourself. Get a Dynon, call Approach FastStack and get a cable, plug it in, hook up a power and ground lead and fly away. Glenn -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Werner Schneider Sent: Thursday, February 18, 2010 8:42 AM Subject: Re: AeroElectric-List: Re: BMA Efis G4 Lite Or go and buy a Dynon Skyview and get 1000$ for your broken G4 <http://www.dynonavionics.com/docs/SkyView_BMA_Trade-In.html> Werner On 18.02.2010 14:28, n395v wrote: > --> AeroElectric-List message posted by: "n395v" > > Best to go to the BMA website or www.vansairforce.net and advertise for G4 lite wanted. Or watch e bay. One or 2 sold recently for less than$500. > > Also try calling Greg Richter- 404-434-3990 > > apparently sometimes he answers and may be able to tell you how to fix it. > > -------- > Milt > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=286915#286915 > > ________________________________________________________________________________
Date: Feb 18, 2010
From: Bob White <bob@bob-white.com>
Subject: Re: S701 Contactor Failure Analysis
I remember using the "no strip" technique many years ago. As I recall, the wrap tool did slit the insulation as it was wrapped around the post so that bare wire was wrapped onto the post. Bob W. "Robert L. Nuckolls, III" wrote: > > At 10:22 PM 2/17/2010, you wrote: > >I'm feeling old... My only hands-on experimental > >circuit making was pre-digital. Over the > >years I'd pickup electronics mags and see > >references to "wire wrapped" terminals and never > >had a clue what it referred to. Now I get it... Thanks. > > > >Bill > > see: > > http://en.wikipedia.org/wiki/Wire_wrap > > This is the modern incarnation used on complex backplanes > where gazillion-layer boards are impractical. The no-strip > version is from way-back-when and it didn't hang around > long. > > Bob . . . > > > > > > -- N93BD - Rotary Powered BD-4 - http://www.bob-white.com Now Rotary Powered Alpine http://www.youtube.com/watch?v=FwceNc2ydN8 Cables for your rotary installation - http://roblinstores.com/ ________________________________________________________________________________
Date: Feb 18, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: S701 Contactor Failure Analysis
At 05:58 AM 2/18/2010, you wrote: > > >If I remember correctly, the wire-wrap technique was only for >microamp level circuits; a few milliamps at the most. I never saw >any wire-wraps for the approx 1 amp that the contactor would >need. Or am I mistaken? Yes, but that was more a function of wire size and size of the post in the specific process. If one adequately understood the physics behind making such joints on 4-cornered posts with the appropriate insulation and tools, I have no doubt that this contactor design could exploit the process. Bob . . . ________________________________________________________________________________
Date: Feb 18, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: S701 Contactor Failure Analysis
At 09:37 AM 2/18/2010, you wrote: > >I remember using the "no strip" technique many years ago. As I recall, >the wrap tool did slit the insulation as it was wrapped around the >post so that bare wire was wrapped onto the post. Yeah . . . I recall that. It WAS a pretty specialized wrapping tool. Bob . . . ________________________________________________________________________________
Subject: Re: BMA Efis G4 Lite
From: "rampil" <ira.rampil(at)gmail.com>
Date: Feb 18, 2010
Actually, according to Larry on the BMA site, they are trying to handle hardware repairs. Check out the bulletin board site. BMA hardware in the field was no less reliable than Dynon or any other non cert hardware. Its been 2 years since BMA stopped development, Dynon still has not caught up with the useful feature list. The main problem with the BMA hardware was that it assumed at least a high school education in electricity to install. Apparently this was a bad assumption. Greg had actually assumed that users would actually want to calibrate their sensors, turns out most installers did not know what that actually meant since no one does it for antediluvian analog hardware. Most people accept 20% accuracy and never know the difference. I used a gold box for 4 years before upgrading to a G4. Never had a hardware problem that was not of my own creation. -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286953#286953 ________________________________________________________________________________
Subject: Re: Basic Electricity....Grrrrr.........
From: "rampil" <ira.rampil(at)gmail.com>
Date: Feb 18, 2010
On the other hand, there's the observation in the Avionics-List last Friday that noted if there was any electrical (not even electronic) literacy, out there, the traffic on this List would drop by 90%. I would think Bob's Seminars would be much more popular! -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=286954#286954 ________________________________________________________________________________
Date: Feb 18, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: S701 Contactor Failure Analysis
At 09:45 AM 2/18/2010, you wrote: >Bob, >That was one of the most educational episodes ever on the >Aeroelectric Connection. >You removed some of the mystery for us. >Thanks, My pleasure my friend . . . it's an extension of a number of tasks I accomplished on the TC side of the house for many years. It was frustrating to me that folks making $multi-million$ decisions had so little knowledge of the physics that described the failure . . . even less on the physics that was proposed to fix it. It took me nearly 8 years to get a brake friction material changed on a motor that was breaking shafts due to a vibration that literally screamed at the most casual observer. I explored dozens of arm-chair suppositions only to return to the original hypothesis and proposal for a fix. Finally got it done but not after a bucket full of money in warranty costs and customer dis-satisfaction went down the drain. I still have a copy of a 6-page letter I wrote to the V.P. of Engineering describing in minute detail how the shafts were failing . . . delighted to receive an e-mail inviting me to a working lunch. Was astounded to find that he wanted to discuss the letter for about 2 minutes and talk about fishing the rest of the time . . . sigh. Here on the list we have a unique opportunity to tap the combined knowledge and experience of folks who's paychecks and promotions do not depend on smoothing the feathers of superiors that know even less about the problem. Bob . . . ________________________________________________________________________________
Date: Feb 18, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Basic Electricity....Grrrrr.........
At 10:29 AM 2/18/2010, you wrote: > >On the other hand, there's the observation in the Avionics-List last Friday >that noted if there was any electrical (not even electronic) literacy, out >there, the traffic on this List would drop by 90%. Not sure that's true . . . folks gravitate into groups for a host of reasons. I suspect the participation here is mixed. Certainly there are individuals who seek customer service style yes/no answers to immediate decisions/problems. It has always been my goal that this be more of a classroom than a "customer support" activity. And given the size of the list (about 1700 at last count) and relatively low traffic, I suspect that most are here to expand their horizons. This is why I (and I'm sure most others) welcome information and ideas that help us DO things with cgreater onfidence, understanding and competence. >I would think Bob's Seminars would be much more popular! I've been rethinking the weekend seminar format as a teaching tool. It's a drink-from-a-firehose which probably has a lower rate of retention than a 3-hour college course . . . which also has a demonstrably poor retention rate. I've been watching my 2.5 year old grandson with great interest. We humans are blessed with a great deal of potential but the process by which that potential is exploited is torturously slow. Retention of ideas and acquisition of skill comes with close attention and interest over long periods of time. The most capable among us did not get that way by taking a course. They acquired it over years of hands-on activity and often in the company of true teachers. This is why Mr. C's parents and grandparents are attentive to the idea that every day experiences should to be framed as teaching moments. What is that? How does it work? Is it easy to break? Can it hurt you? Are there inappropriate usages that attack the liberty of others or destroys property? I'm not suggesting that this little guy is being treated like a high-school student . . . certainly everything offered has to be tailored to his level of understanding. But the process of becoming 'educated' goes far beyond any time one spends in the formal classroom. One gets and holds his attention by making it fun. The AeroElectric-List is an opportunity for the interested and attentive to read about ideas and their supporting physics go by over as long much time as one is willing to expend on the effort. This is why I encourage folks to write about any whippy new discovery, any unexplained event (contactor failures?), or ask any question. It's then up to those who can contribute to an exploration of the question or understanding of the answers have an opportunity to become true teachers. We all have things to learn, things to offer and opportunities to share in the pleasure of advancing our collective art. The process is slow and laborious . . . and the older we get, the more laborious it becomes. One of my teachers once opined, "The day you stop learning the first day of your decline toward insignificance." Mr. C is one of my strongest motives to add to my own catalog of understanding and skills to share with him as he grows up. Folks here on the list are participants in that task. You all contribute to expansion of my own horizons which I will ultimately pass down to the next generation. Bob . . . ________________________________________________________________________________
Date: Feb 18, 2010
From: Bill Mauledriver Watson <MauleDriver(at)nc.rr.com>
Subject: Re: Basic Electricity....Grrrrr.........
rampil wrote: > > On the other hand, there's the observation in the Avionics-List last Friday > that noted if there was any electrical (not even electronic) literacy, out > there, the traffic on this List would drop by 90%. > > I would think Bob's Seminars would be much more popular! > > -------- > Ira N224XS > I think the level of electrical, and even electronic, literacy is a bit higher here than one might think. An analogy I might make is with instrument flight. I'm IFR literate (talk the talk, been there-done that, remember most rules, read most pubs), but not proficient or current. Having grown up with my Dad's scratch built TV, testing vacuum tubes for fun, studying for my Class III, practicing morse code, recyling components from surplus boards, and building pre-proportional RC aircraft, I'm electrically literate but not proficient or current. And 30+ years in the computer industry doesn't necessarily cover the same ground. For those of us not in the business or practicing an electrical/electronics hobby on a daily basis, this list is a pretty good substitute. Of course fooling around with OBAM aircraft can be an electrically engaging pursuit... and I think what we all see here is a lot of literate people building skills while regaining a little currency and proficiency as they work their projects. Ohm's law?? On at least 2 occassions over the last year I can recall relearning that simple little equation as a fuse fried or some unit dimmed. I learned it, I know what it is, but haven't applied it in so long that a little rediscovery is to be expected. Anyway, I'm REALLY enjoying this list and everyone on it. Thanks to Bob in particular. Bill "losing proficiency with sanding block in hand" Watson ________________________________________________________________________________
Date: Feb 18, 2010
From: Jeff Page <jpx(at)qenesis.com>
Subject: Failure modes with Z12
I am still vacillating between Z13/8 and Z12. I intend to use two electronic ignitions. The only thing that concerns me is an overvoltage event that burns out both ignitions. Probably very rare, considering the robust design, but perhaps a lightning strike, or the failure of an overvoltage module ? Z12 would isolate the two and alleviate my concern. Second, I frequently cruise at 2200rpm and the output of the SD-8 would be only about 5A. For 0.8 pounds and $79 more, with an insignificant balance improvement, I can buy a 40A and 20A alternator instead, which is very tempting. The concept of the essential bus diode is not used in Z12, so now we get to my question. It appears that after a failure of either battery contactor, there is no configuration to supply power to the corresponding battery bus. So duration of flight is limited by the battery capacity, rather than the capacity of the remaining alternator to supply all the ships loads with the cross feed contactor engaged. What change could be safely made to provide power to both battery buses without negatively impacting other features of Z12 ? Thanks ! Jeff Page Dream Aircraft Tundra #10 ________________________________________________________________________________
Subject: Re: Basic Electricity....Grrrrr.........
From: "rampil" <ira.rampil(at)gmail.com>
Date: Feb 18, 2010
Hey Bill, Just remember that wax on - wax off with a sanding block generates proficiency too (and muscles)! -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287030#287030 ________________________________________________________________________________
From: "Dave" <dave(at)coltnet.net>
Subject: Re: Basic Electricity....Grrrrr.........
Date: Feb 18, 2010
> > > I've been rethinking the weekend seminar format as > a teaching tool. It's a drink-from-a-firehose which > probably has a lower rate of retention than a 3-hour > college course . . . which also has a demonstrably poor > retention rate. Bob, I would love to attend one of your seminars, but due to the distance, work and a number of other reasons of life getting in the way of life, I have been unable to participate. Have you considered a set of seminar dvds. Even though they seminars are a drink from the firehose. The dvd/s could allow a review as required and a chance for some of us to drink from the firehose who may never get to drink in person. Thanks for all of your contributions to the OBAM world. Dave > ________________________________________________________________________________
From: BobsV35B(at)aol.com
Date: Feb 18, 2010
Subject: Re: Basic Electricity....Grrrrr.........
Good Evening Dave, I was able to attend one of Bob's seminars near Milwaukee a couple of years ago. Well worth the time and if the opportunity presents itself. I will attend again. Firehose or not, well worth the time! Happy Skies, Old Bob In a message dated 2/18/2010 9:04:53 P.M. Central Standard Time, dave(at)coltnet.net writes: --> AeroElectric-List message posted by: "Dave" > > > I've been rethinking the weekend seminar format as > a teaching tool. It's a drink-from-a-firehose which > probably has a lower rate of retention than a 3-hour > college course . . . which also has a demonstrably poor > retention rate. Bob, I would love to attend one of your seminars, but due to the distance, work and a number of other reasons of life getting in the way of life, I have been unable to participate. Have you considered a set of seminar dvds. Even though they seminars are a drink from the firehose. The dvd/s could allow a review as required and a chance for some of us to drink from the firehose who may never get to drink in person. Thanks for all of your contributions to the OBAM world. Dave > ________________________________________________________________________________
Date: Feb 18, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Failure modes with Z12
At 01:34 PM 2/18/2010, you wrote: > >I am still vacillating between Z13/8 and Z12. > >I intend to use two electronic ignitions. The only thing that >concerns me is an overvoltage event that burns out both ignitions. >Probably very rare, considering the robust design correct . . . not a useful point of concern . . . >but perhaps a lightning strike, No guarantees at all for lightning strike. I'm pretty sure Klaus hasn't included lightning immunity in his design goals . . . and in any case, system architecture wouldn't offer any 'protection' except for a few of the possible energy conduction pathways. One just generally needs to stay away from > or the failure of an overvoltage module? Ov module failures don't cause ov conditions. OV module failures would not catch and stop an OV condition . . . AFTER a regulator failure. That's dual failures on a single tank of fuel. Exceedingly unlikely to the point > Z12 would isolate the two and alleviate my concern. Z12 is a single system with two alternators. Z13/8 is a variation on the same theme. Only Z-14 provides near-total isolation between separate systems . . . assuming your willing to let this concern drive you decisions. >Second, I frequently cruise at 2200rpm and the output of the SD-8 >would be only about 5A. For 0.8 pounds and $79 more, with an >insignificant balance improvement, I can buy a 40A and 20A alternator >instead, which is very tempting. What are your design goals? Under conditions of main alternator failure, could you NOT cruise as fast as red line for the remainder of the flight? >The concept of the essential bus diode is not used in Z12, so now we >get to my question. It appears that after a failure of either battery >contactor, there is no configuration to supply power to the >corresponding battery bus. So duration of flight is limited by the >battery capacity, rather than the capacity of the remaining alternator >to supply all the ships loads with the cross feed contactor engaged. >What change could be safely made to provide power to both battery >buses without negatively impacting other features of Z12 ? You must be talking about Z-14. Are you telling us that both batteries are critical for sustained flight? What loads are you running from each of the battery busses that offers this condition? Elegant system design eliminates all single points of failure that put the mission at risk. You need to make a list of the things you absolutely need to continue flight to airport of intended destination. For me, flying a spam can, that means shut down the electrical system entirely and go to flight-bag hand-helds. When I have the airport in sight, I've got what ever the battery contains to finish the flight. The decision is not made by asking us for advice on your concerns. The decision is driven by failure mode effects analysis stacked against the equipment you plan to carry on the panel and in the flight bag. Where will those devices will get a couple hours of energy when the alternator quits (which is increasingly rare). Confidence only arises from a calculated Plan-B. Bob . . . ________________________________________________________________________________
From: "LINDA WALKER" <l.p(at)talk21.com>
Subject: Re: BMA Efis G4 Lite
Date: Feb 19, 2010
Thanks for all the comments, constructive and otherwise, to this request for help. Greg Richter is kindly going to make the repair and would like the community to know that he is reachable by e-mail at: greg(at)bluemountainavionics.com. I would think that this is the correct way to reach him despite his home telephone number being out there. Patrick Elliott ________________________________________________________________________________
Subject: Failure modes with Z12
Date: Feb 19, 2010
From: <longg(at)pjm.com>
Jeff, Bob's last 3 paragraphs put everything together. The risk adverse individual (my wife) will question every level and only accept one final outcome - total assumed security. That isn't going to happen. Look at all the GA wrecks in the last few days - yikes. In a few year we'll be lucky if we're allowed to fly. So let's talk about failure modes as Bob mentions below. For your example assume the worst case which is probably over water, right? Ok, personally I have two Klaus jobs (wow, this guy is famous - just the mention of the name Klaus, I'm so jealous), any-who I have the SD-8 and a Dynon with HSI. So everything goes to hell, Don't tell Bob but I use two batteries with Z-13 like Klaus recommends to run one module, so live it up. This battery is 4.5 ah (very small), but the Klaus job will run down to 5 volts (now, you're heading for the Bahamas and both alternators die (hardly likely unless you've been pouring sand into them) halfway between Palm Beach and Bimini - oh sh*%). Ok, with my 1-2 amp Dynon (internal battery) and my sometimes 3 amp SL30 I can still do a non-precision landing at Bimini after running for an hour (the 50 miles or so) on battery(s). Everything else is off and my Dynon is running on internal battery (that sucker runs min 1.5 hours just on the internal 16 volts it has saved up, and oh, since I have two Dynons I can then turn on the other one and..) When I get near Bimini, I turn on the radio because I've been monitoring my progress as Bob mentioned with my handheld GPS and spare batteries. Hell, if I'm really nuts I can even use my handheld radio to talk to the Bimini approach. The Klaus jobs won't know the difference and if you're really cocky you can turn one off and pull 5 volts for several hours before even the 17 ah battery dies. If that's used up, I kill it and move to my backup 4.5 ah battery and skip over Bimini and keep going to Nassau. You get the point. Once you get setup, you simulate this on the ground. If your system is 100%, you'll be sitting in your plane a long time waiting for the battery to give up. Moral of the story - Keep the batteries in your toys fresh and you'll keep flying. Batteries and oil are cheap, don't skimp on either. >From Bob N> " Elegant system design eliminates all single points of failure that put the mission at risk. You need to make a list of the things you absolutely need to continue flight to airport of intended destination. For me, flying a spam can, that means shut down the electrical system entirely and go to flight-bag hand-helds. When I have the airport in sight, I've got whatever the battery contains to finish the flight. The decision is not made by asking us for advice on your concerns. The decision is driven by failure mode effects analysis stacked against the equipment you plan to carry on the panel and in the flight bag. Where will those devices will get a couple hours of energy when the alternator quits (which is increasingly rare)." > -----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, February 18, 2010 8:28 PM Subject: Re: AeroElectric-List: Failure modes with Z12 At 01:34 PM 2/18/2010, you wrote: > >I am still vacillating between Z13/8 and Z12. > >I intend to use two electronic ignitions. The only thing that >concerns me is an overvoltage event that burns out both ignitions. >Probably very rare, considering the robust design correct . . . not a useful point of concern . . . >but perhaps a lightning strike, No guarantees at all for lightning strike. I'm pretty sure Klaus hasn't included lightning immunity in his design goals . . . and in any case, system architecture wouldn't offer any 'protection' except for a few of the possible energy conduction pathways. One just generally needs to stay away from > or the failure of an overvoltage module? Ov module failures don't cause ov conditions. OV module failures would not catch and stop an OV condition . . . AFTER a regulator failure. That's dual failures on a single tank of fuel. Exceedingly unlikely to the point > Z12 would isolate the two and alleviate my concern. Z12 is a single system with two alternators. Z13/8 is a variation on the same theme. Only Z-14 provides near-total isolation between separate systems . . . assuming your willing to let this concern drive you decisions. >Second, I frequently cruise at 2200rpm and the output of the SD-8 >would be only about 5A. For 0.8 pounds and $79 more, with an >insignificant balance improvement, I can buy a 40A and 20A alternator >instead, which is very tempting. What are your design goals? Under conditions of main alternator failure, could you NOT cruise as fast as red line for the remainder of the flight? >The concept of the essential bus diode is not used in Z12, so now we >get to my question. It appears that after a failure of either battery >contactor, there is no configuration to supply power to the >corresponding battery bus. So duration of flight is limited by the >battery capacity, rather than the capacity of the remaining alternator >to supply all the ships loads with the cross feed contactor engaged. >What change could be safely made to provide power to both battery >buses without negatively impacting other features of Z12 ? You must be talking about Z-14. Are you telling us that both batteries are critical for sustained flight? What loads are you running from each of the battery busses that offers this condition? Elegant system design eliminates all single points of failure that put the mission at risk. You need to make a list of the things you absolutely need to continue flight to airport of intended destination. For me, flying a spam can, that means shut down the electrical system entirely and go to flight-bag hand-helds. When I have the airport in sight, I've got what ever the battery contains to finish the flight. The decision is not made by asking us for advice on your concerns. The decision is driven by failure mode effects analysis stacked against the equipment you plan to carry on the panel and in the flight bag. Where will those devices will get a couple hours of energy when the alternator quits (which is increasingly rare). Confidence only arises from a calculated Plan-B. Bob . . . ________________________________________________________________________________
Subject: Re: Failure modes with Z12
From: "user9253" <fran4sew(at)banyanol.com>
Date: Feb 19, 2010
> "I am still vacillating between Z13/8 and Z12." If you are undecided, go with Z-13/8. It is simpler, costs less, and weighs less than Z-14 and is more reliable than most factory-built systems. You are concerned about a battery contactor failure. How will you recognize that a battery contactor failure has occurred? There might not be any symptoms because the alternator would probably keep working. It would be necessary to monitor the battery voltage to recognize a problem. Even with a failed battery contactor, voltage on the main power distribution bus will be normal as long as the alternator keeps working. The low voltage warning light on the regulator does not warn of low battery voltage due to contactor failure. If using Z-13/8, turning on the E-Bus Alternate Feed Switch will provide a parallel path around the contactor from the main alternator to the battery. Although voltage will be dropped across the diode and current is limited by the 15 amp fuse, it should be adequate for a fuel pump and ignition. In addition, the aux alternator is connected to the battery side of the main contactor. Multiple failures would have to occur before power is lost to critical engine ignition and fuel systems that are connected to the battery. You might consider connecting one ignition and fuel pump to the battery bus and the other set to the E-Bus. Doing so insures that one set will keep working in the event of a bad electrical connection. What do you think Bob N.? Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287195#287195 ________________________________________________________________________________
Date: Feb 19, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Failure modes with Z12
At 10:44 AM 2/19/2010, you wrote: > > > > "I am still vacillating between Z13/8 and Z12." > If you are undecided, go with Z-13/8. It is simpler, costs less, > and weighs less than Z-14 and is more reliable than most factory-built systems. > You are concerned about a battery contactor failure. How will > you recognize that a battery contactor failure has occurred? There > might not be any symptoms because the alternator would probably > keep working. It would be necessary to monitor the battery voltage > to recognize a problem. Even with a failed battery contactor, > voltage on the main power distribution bus will be normal as long > as the alternator keeps working. The low voltage warning light on > the regulator does not warn of low battery voltage due to contactor failure. > If using Z-13/8, turning on the E-Bus Alternate Feed Switch will > provide a parallel path around the contactor from the main > alternator to the battery. Although voltage will be dropped across > the diode and current is limited by the 15 amp fuse, it should be > adequate for a fuel pump and ignition. In addition, the aux > alternator is connected to the battery side of the main > contactor. Multiple failures would have to occur before power is > lost to critical engine ignition and fuel systems that are > connected to the battery. You might consider connecting one > ignition and fuel pump to the battery bus and the other set to the > E-Bus. Doing so insures that one set will keep working in the > event of a bad electrical connection. > What do you think Bob N.? >Joe > >-------- >Joe Gores > > >Read this topic online here: > >http://forums.matronics.com/viewtopic.php?p=287195#287195 > > Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ ________________________________________________________________________________
Date: Feb 19, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Failure modes with Z12 (ignore earlier)
I'm eagerly awaiting system restore disks for my computer . . . seems it's been invested with little gremlins that are not virii/malware but instead associated with every software designer's desire to link his/her application with everyone else. After 5-7 years of tug-a-war between all those applications . . . their little squabbles are now spilling out of the play-pen. Makes the computer do silly things like "send now" before I've even edited the message! . . . ain't this 'lectronix stuff wunderful . . . At 10:44 AM 2/19/2010, you wrote: > "I am still vacillating between Z13/8 and Z12." If you are undecided, go with Z-13/8. It is simpler, costs less, and weighs less than Z-14 and is more reliable than most factory-built systems. Agreed . . . keeping in mind that when airplanes come down or even get into trouble with root causes in electrical systems, somebody had to do something really . . . uh . . . what's the PC term . . . inappropriate? Stacking backup on top of backup without a carefully considered FMEA (failure mode effects analysis) backed up with equally well considered Plan-B is fraught with risk. An incident I'm working on right now involves seemingly cool approaches to redundancy that set the stage for single-points of failure for power to both ignition systems in spite of TWO properly working alternators and TWO charged batteries. You are concerned about a battery contactor failure. How will you recognize that a battery contactor failure has occurred? Excellent question that drove the features of our 9011 multi-channel OV/LV monitoring device. A channel dedicated to monitoring battery voltage will flag a battery contactor that has opened after pre-flight . . . There might not be any symptoms because the alternator would probably keep working. It would be necessary to monitor the battery voltage to recognize a problem. Even with a failed battery contactor, voltage on the main power distribution bus will be normal as long as the alternator keeps working. The low voltage warning light on the regulator does not warn of low battery voltage due to contactor failure. Correct. If using Z-13/8, turning on the E-Bus Alternate Feed Switch will provide a parallel path around the contactor from the main alternator to the battery. Although voltage will be dropped across the diode and current is limited by the 15 amp fuse, it should be adequate for a fuel pump and ignition. In addition, the aux alternator is connected to the battery side of the main contactor. Multiple failures would have to occur before power is lost to critical engine ignition and fuel systems that are connected to the battery. You might consider connecting one ignition and fuel pump to the battery bus and the other set to the E-Bus. Yes! Plans-B should also consider shutting down one of two ignition systems during the endurance phase of flight at altitude. Keep in mind that there are many, Many, MANY OBAM aircraft flying with one electronic ignition and one mag. For all practical purposes the airplane flies on a single ignition. 95% of all performance gains come when you add the first electronic ignition . . . the mag is coasting. The second electronic system is untaxed redundancy that consumes power from your limited resources in the endurance mode of flight. Doing so insures that one set will keep working in the event of a bad electrical connection. What do you think Bob N.? Excellent example of the FMEA thought processes. In the accident case I cited, simple direct feeds to EACH ignition from SEPARATE batteries would have offered a near bullet-proof hedge against risks. In a Z-13 or Z-12 system, feeding one ignition from the battery bus and the other from the e-bus is a good move. Primary and secondary fuel delivery systems should be spread around too. There's no single-golden-righteous recipe for success here. There are no two OBAM aircraft wired the same way. This FMEA thingy is something as necessary as learning how to buck a good rivet. Bob . . . ________________________________________________________________________________
From: "emrath" <emrath(at)comcast.net>
Subject: S701 Contactor Failure Analysis
Date: Feb 19, 2010
Bob, Thanks for taking time to do this. Very interesting. I hope my replacement, provided by B&C "gratis" was not manufactured on the same day...... Marty From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> Subject: AeroElectric-List: S701 Contactor Failure Analysis Last year, Marty Emrath told us about the failure of a new contactor he had purchased from B&C. B&C replaced the contactor but Marty was justifiably curious as to root cause of the failure. I offered to document a tear-down analysis and Marty sent me the carcass. I was looking for something fun to do this afternoon so I took the dead puppy apart. The pictures at . . . http://www.aeroelectric.com/Pictures/Contactors/S701_Failure_Teardown/ Are pretty much self explanatory. One thing is for certain. This product is much more sophisticated than its ancestors that first took to the air in a C-140. The last picture tells the tale . . . http://www.aeroelectric.com/Pictures/Contactors/S701_Failure_Teardown/TearDo wn_10.jpg Seems the assembler wasn't really awake yet when this device went across their work station. One coil wire was poorly soldered to its terminal . . . the other had no solder at all. Thanks for sharing your experience with us Martin! Bob . . . ________________________________________________________________________________
Subject: fuel pressure sender ground
From: "messydeer" <messydeer(at)yahoo.com>
Date: Feb 19, 2010
Hi! I just got my Steward Warner fuel pressure sender and am wondering what a good way to get a ground lead from it would be. The first pic shows its 1/8" npt stud threaded into a T fitting in my mockup. Tech support said to use the npt stud. But I can't imagine getting a tight fit with a ground ring that way, without making the actual fitting looser. He also said if I needed to, the top of the can near the edge could be tapped. Any ideas? Thanks, Dan -------- Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287245#287245 Attachments: http://forums.matronics.com//files/fuel_regulator_and_pressure_sender_196.jpg http://forums.matronics.com//files/sw_pressure_sender_139.jpg ________________________________________________________________________________
Subject: Re: fuel pressure sender ground
From: "rampil" <ira.rampil(at)gmail.com>
Date: Feb 19, 2010
What close fit? the size of the ring is not important as long as it slides over the NPT. If the NPT Tee does not compress the ring, put a jam nut over the ring. -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287257#287257 ________________________________________________________________________________
Subject: Re: Failure modes with Z12
From: "user9253" <fran4sew(at)banyanol.com>
Date: Feb 19, 2010
Bob, I can not show you where you are wrong because you said nothing wrong and your electrical drawings are very hard to improve upon. Comments in my previous post were not meant to criticize or to suggest changes. I was only trying to explain how the circuit worked and that there is no reason to be overly concerned about a battery contactor failure in flight and that no changes to Z-13/8 are required for dual electronic ignition (other than to tap power from two separate points). When I asked for your opinion at the end of my previous post, I was asking for your approval and to correct anything that I may have said that was incorrect. I hope that you did not take it any other way. I have been reading the AeroElectric List for a couple of years and have learned a lot and respect your work and opinions. I commend you for offering free advice and taking time to answer electrical questions from home-builders. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287259#287259 ________________________________________________________________________________
Date: Feb 19, 2010
Subject: Re: fuel pressure sender ground
From: "Matt Prather" <mprather(at)spro.net>
Most NPT is tapered. As such, my thinking is that the threaded joint must become tight by the binding of the taper, not by contacting facing surfaces.. If the installed lug (or jam nut) causes contacting of the facing surfaces, I might be a bit concerned about long term sealing of the joint. http://en.wikipedia.org/wiki/National_pipe_thread Regards, Matt- > > What close fit? > the size of the ring is not important as long as it slides over the > NPT. If the NPT Tee does not compress the ring, put a jam nut > over the ring. > > -------- > Ira N224XS > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=287257#287257 > > ________________________________________________________________________________
Subject: Re: fuel pressure sender ground
From: "messydeer" <messydeer(at)yahoo.com>
Date: Feb 19, 2010
Bingo! That's exactly what I am concerned about, Matt :-) Mr. Tech Dude mentioned tapping a 1/8" NPT washer...I suppose if there is room enough (haven't gotten the aluminum T fitting to replace the brass one in the pic) and if I tap it large enough so it doesn't prevent the stud from going in all the way then it might work...hmm... -------- Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287268#287268 ________________________________________________________________________________
Date: Feb 19, 2010
From: Peter Pengilly <peter(at)sportingaero.com>
Subject: Re: fuel pressure sender ground
Hose clamp around the sender to trap a ground wire? Solder a wire on to the sender body? Bolt sender to a monifold bolted (and grounded) to the firewall (or ground the mounting bolt)? Ground wire on the circular metal thing? BTW not sure I would use PVC pipe with push on fittings on a fuel line under pressure! I use teflon braided pipe with integral firesleeve. Peter messydeer wrote: > > Hi! > > I just got my Steward Warner fuel pressure sender and am wondering what a good way to get a ground lead from it would be. The first pic shows its 1/8" npt stud threaded into a T fitting in my mockup. Tech support said to use the npt stud. But I can't imagine getting a tight fit with a ground ring that way, without making the actual fitting looser. > > He also said if I needed to, the top of the can near the edge could be tapped. > > Any ideas? > > Thanks, > Dan > > -------- > Dan > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=287245#287245 > > > Attachments: > > http://forums.matronics.com//files/fuel_regulator_and_pressure_sender_196.jpg > http://forums.matronics.com//files/sw_pressure_sender_139.jpg > > > ________________________________________________________________________________
Subject: Re: fuel pressure sender ground
From: "rampil" <ira.rampil(at)gmail.com>
Date: Feb 19, 2010
If worry about the sealing is your concern, use PTFE compound on the joint. If structural integrity is your issue, you should not be using the old VDO automotive sensor in the first place as it has a huge moment arm and NPT is not aerospace qualified. ANPT is better but is not compatible with highest quality hose like Aeroquip 666. If you are still wanting to use the VDO like Rotax used to for oil pressure, strap it with a stainless hose clamp as suggested and safety wire it to not rotate. Grounding at the clamp is optional but works if clean and the sensor can is not corroded since under the clamp will not be as anaerobic as under a jam nut to a ring terminal - i.e., more rust. -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287284#287284 ________________________________________________________________________________
Subject: Re: fuel pressure sender ground
From: "messydeer" <messydeer(at)yahoo.com>
Date: Feb 19, 2010
Thanks, guys :-) I could have mentioned this is mockup stuff, not the real McCoy. But $0.25/ft hose would be a better budget fit! The tee shown is a brass one from the hardware store. I'll replace it with an aluminum when it's delivered next week, along with a bunch of other fittings. Grounding to the adel clamp sounds reasonable. I could take off the pad on the clamp holding the tee, then slip a ring over the bolt holding the two clamps together. -------- Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287289#287289 Attachments: http://forums.matronics.com//files/fuel_regulator_with_clamps_on_tee_152.jpg ________________________________________________________________________________
Subject: Re: fuel pressure sender ground
From: "al38kit" <alfranken(at)msn.com>
Date: Feb 19, 2010
First, to answer your question...If you check the resistance from the case of the transducer to the engine case and find it to be minimal, forget about a separate ground wire and ensure the case of the engine is common to your electrical system. Now for the biggie... I would scrap this entire installation of the transducer and mount it on a braided flexible line with a fitting having a flow restrictor. It is a bad idea to mount any of these transducers in the manner you are attempting and many instrument manufacturers do NOT recommend hard mounting them to the engine... I recall reading an accident report about a Questair Pilot who had mounted one on some tubing...it failed in flight and he got to spend some time in the mountains with a broken leg...alone. Fittings are not good mounts in a vibration environment. Just something to think about now... Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287305#287305 ________________________________________________________________________________
Subject: Re: fuel pressure sender ground
From: "messydeer" <messydeer(at)yahoo.com>
Date: Feb 19, 2010
Thanks A. :-) I understand your comments about the electrical ground. As far as the chance of this type of unit mounted in this manner failing, I'd like some clarification. I take it you're saying this type of pressure sender is okay, but not the way it is installed/supported, right? And the Questair had one 'on some tubing'. Was this rigid tubing or hose? Seems an installation that would fix the 1-lb sender to the engine mount would work, as long as flexible hose goes in and out of it. -------- Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287311#287311 ________________________________________________________________________________
Date: Feb 19, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: B&C Regulators and water-falls
Received at AeroElectric Connection today . . . Bill Harrelson and I had a chance to review the investigation and preliminary causes of an in-flight fire in a Lancair IV-P that occurred last spring (2009). The findings and conclusions are not yet established, but the investigator felt that some of the information discovered was not in question, and would be useful to the experimental community. We agreed to help spread the word=85as follows: The accident aircraft experienced an in-flight battery fire of the secondary electrical system shortly after takeoff. The pilot was able to return to the airport and extinguish the fire in the tail section of the aircraft after landing. The battery, case, and nearby components were consumed/destroyed, and the aircraft fuselage sustained significant heat damage from the aft pressure bulkhead to the elevators/rudder. The cause of the fire has not been absolutely determined, but the lead/acid battery vents had apparently been obstructed, resulting in a case rupture and venting of hydrogen gas into the tail section of the airplane. The exact cause of this apparent over pressurization and rupture awaits additional information and analysis. This finding and the final NTSB report are expected within a month and we will disseminate this report through the LML and LOBO newsletter. One initial result of the investigation was that the B&C regulator for the secondary electrical system was inoperative upon post-flight analysis. The NTSB investigator conducted a detailed examination and analysis of the defective unit and determined that the electrical design was robust and appropriate to the task. The unit was mounted to the engine side of the firewall with the spade terminal connectors projecting to the side of the aircraft. This unit is not sealed, and at some point liquid (probably water) entered the metal box, most likely through the opening around the spade terminals, Hmmm . . . They speak of "spade" terminals . . . I presume they're referring to the screw-terminal strip. and filled it to a depth of 1/4 to 1/2 inch. The liquid allowed arcing among internal components and to the case ground, leaving carbon tracks on the circuit board and case, and destroying the electrical functionality. It is certain that water and electronics don't mix well. I'm not certain that mounting on the firewall is an automatic no-no . . . we've been tying stuff to firewalls since day-one but it IS a unique environment. Shucks, look at all the firewall mounted electro-whizzies on this airplane . . . http://aeroelectric.com/Pictures/Wiring_Technique/Firewall_Ckt_Protection.jp g Way back when, Cessna modified the cowl attach fittings to set on shock mounts instead of the firewall bulkhead. It reduced cabin noise significantly. However, the gap around the aft edge of the "floating cowl" allowed water to run down the windshield of parked aircraft right down the firewall. Believe it or not, there was a period of time when Cessna was adding brushed on EPOXY seals to the S701 style battery and starter contactors! Seems that on a nice hot day, the contactor would exhale. Then a nice cool shower came along and bathed the contactor which inhaled liquid water thought the non-hermetic cap seals. Now the water could only get out as a vapor through repeated atmospheric transfers of gas from the semi-tight enclosure. Needless to day, even epoxy sealing was only marginally successful in forestalling premature contactor death due to rust. Those were the years I did my first alternator regulator design for Cessna that featured an injection molded case with o-ring sealed lid. It was a couple bux more expensive than somebody else's design that was manually doped with sealant at the enclosure gaps. A risky, process sensitive design . . . but they liked it. A review of installation instructions provided with B&C regulators recommends they be installed inside the cockpit or in a similar environmentally-protected area. This regulator was mounted inside the engine compartment, as we believe are the vast majority of Lancair installations. When so installed, regulators are subject to additional heat and cooling stresses, as well as water/solvents from engine cleaning and other maintenance when the cowling is removed. If mounted in any position other than with the spades down, liquid can enter in the area of the spade terminals and will then be trapped within the lower part of the enclosure, immersing part of the main circuit board. Right . . . so mount the terminal strips down and be cognizant of the fact that you can't just spray everything down when cleaning the engine. B&C suffered some bearing failures in alternators way back when due to over-zealous use of high- pressure, soapy-water. If you are still building and have the option, review the B&C recommendations on mounting location and consider locating your B&C regulator(s) inside the cockpit; preferably with the spades down if there is any possibility of liquid exposure. No matter the location, mount them in such a way that they cannot ingest and retain water. Excellent suggestion which applies to ALL accessories not suitably protected from either nature or owner-generated moisture issues. Shucks, we had many killobux of warranty hassles on the C337 that featured a really nice radio access hatch in the cowl deck forward of the windshield but aft of the firewall. Seems the hatch seals liked to leak a drip into the radios. If you are not able to locate the regulator(s) as recommended by B&C, consider shielding the terminal strip area from liquids. We expect to contact B&C about the feasibility of other improvements that could be made, but will refrain from making any recommendations until we receive their comments. All good suggestions and plans for action . . . but I'll suggest overly simplistic. These are increasingly complex machines with features that do not fare well when subjected to soapy water, snow, ice, rain-water, ozone, hydraulic fluids, spilled 7-up, etc. etc. By the way, when the B&C "regulators" were originally conceived, we considered offering the regulator, LV-protection and LV-warn as a trio of separate components. But it was our design goal that EVERY user of B&C regulators received the benefit of OV-protection and active notification of low voltage. Hence the rather expensive "regulator" which was really an "alternator control system". The failure in the Lancair points out a weakness of that design philosophy. Filling the box with water poses a risk of killing both OV protection --AND-- regulator functionality. I.e., SINGLE POINT OF FAILURE that produces an uncontrolled runaway. Given what we know now, would we have done it any different back then? Hard to tell. We can learn from this failure instance and be cognizant of as many risks as one can deduce individually and collectively. This is what FMEA is all about. The process benefits greatly from lessons learned . . . whether on last months's battery fire or the last century=92s leaky cowls. Bob . . . ________________________________________________________________________________
Date: Feb 19, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Failure modes with Z12
> When I asked for your opinion at the end of my previous post, I > was asking for your approval and to correct anything that I may > have said that was incorrect. I hope that you did not take it any > other way. I have been reading the AeroElectric List for a couple > of years and have learned a lot and respect your work and > opinions. I commend you for offering free advice and taking time > to answer electrical questions from home-builders. Joe, I just re-read my posting. I'm sorry if I sounded reproachful in any way. Please know that it was unintentional. I abhor such behavior in myself and discourage it in others. In fact, I think I complimented your organization of the FEMA thought process and attempted to amplify that stream of ideas. To the best of my recollection, your postings have always been helpful and technically accurate. I value your participation on the List. Bob . . . ________________________________________________________________________________
Date: Feb 20, 2010
Subject: Re: fuel pressure sender ground
From: rparigor(at)suffolk.lib.ny.us
Hi Dan "I just got my Steward Warner fuel pressure sender and am wondering what a good way to get a ground lead from it would be." I have a remote oil sender that is attached to a non conductive line on my Rotax 914. One option is to put some sort of spacer that gets tightly squeezed between sender and fitting and attach to that. I have heard of just washers used, thin NPT nuts or you could be an idiot like I am going to be and turn a precision spacer and make it so I get a tight fit. Like Ira said it dosen't have to be a real tight fit on NPT, butI prefer that, but length is critical so you get enough tension and allow NPT to seal. To be a further idiot I am also considering installing a hose clamp on the OD of sender catching another ground to a piece of brass or copper held by clamp. I have other senders with fairly small brass hex. I will install senders leaving first few threads free of Loctite or sealant in hopes it gets a good ground to block, but will also installMcMaster Carr small 3/8" wide stainless steel mini hose calmps (like automobile fuel injection fuel line clamps) grabbing a piece of copper or brass and use that as an aux. ground. Stupid, simple and looks very nice as well. Ron Parigoris ________________________________________________________________________________
Date: Feb 20, 2010
From: <ronburnett(at)charter.net>
Subject: Re: B&C Regulators and water-falls
My firewall mounted tray supplied for my electric dependent engine contains two Oddessey 680 batts., but I drilled lightening holes in it which should also preclude water/glycol retension. Ron Burnett RV-6A forever finishing Subaru H4-- ---- "Robert L. Nuckolls wrote: ============ Received at AeroElectric Connection today . . . Bill Harrelson and I had a chance to review the investigation and preliminary causes of an in-flight fire in a Lancair IV-P that occurred last spring (2009). The findings and conclusions are not yet established, but the investigator felt that some of the information discovered was not in question, and would be useful to the experimental community. We agreed to help spread the wordas follows: The accident aircraft experienced an in-flight battery fire of the secondary electrical system shortly after takeoff. The pilot was able to return to the airport and extinguish the fire in the tail section of the aircraft after landing. The battery, case, and nearby components were consumed/destroyed, and the aircraft fuselage sustained significant heat damage from the aft pressure bulkhead to the elevators/rudder. The cause of the fire has not been absolutely determined, but the lead/acid battery vents had apparently been obstructed, resulting in a case rupture and venting of hydrogen gas into the tail section of the airplane. The exact cause of this apparent over pressurization and rupture awaits additional information and analysis. This finding and the final NTSB report are expected within a month and we will disseminate this report through the LML and LOBO newsletter. One initial result of the investigation was that the B&C regulator for the secondary electrical system was inoperative upon post-flight analysis. The NTSB investigator conducted a detailed examination and analysis of the defective unit and determined that the electrical design was robust and appropriate to the task. The unit was mounted to the engine side of the firewall with the spade terminal connectors projecting to the side of the aircraft. This unit is not sealed, and at some point liquid (probably water) entered the metal box, most likely through the opening around the spade terminals, Hmmm . . . They speak of "spade" terminals . . . I presume they're referring to the screw-terminal strip. and filled it to a depth of 1/4 to 1/2 inch. The liquid allowed arcing among internal components and to the case ground, leaving carbon tracks on the circuit board and case, and destroying the electrical functionality. It is certain that water and electronics don't mix well. I'm not certain that mounting on the firewall is an automatic no-no . . . we've been tying stuff to firewalls since day-one but it IS a unique environment. ________________________________________________________________________________
Subject: Re: fuel pressure sender ground
From: "al38kit" <alfranken(at)msn.com>
Date: Feb 20, 2010
I think the sender is fine. Regarding the failure I read about, yes it was on a rigid tube, and I believe the tubing failed...the mode of failure would be similar to what you could expect with a few fittings stacked together and the sender mounted to them. >From what I can see in your photos, using a large Adel clamp around the sender body and a second smaller clamp to the engine mount, mating the two together would be a good way to support the sender... Then use a steel braided hose to connect the sender to the pressure port. If there is a two conductor sender available (one with a ground), I'd look into getting one. The good thing is that as this is a fuel pressure sender, if it fails and the engine is still running, it's just a system abnormal.... If it's an oil pressure sender and it indicates zero, you have a more complex situation. Hope this helps. Al messydeer wrote: > Thanks A. :-) > > I understand your comments about the electrical ground. > > As far as the chance of this type of unit mounted in this manner failing, I'd like some clarification. I take it you're saying this type of pressure sender is okay, but not the way it is installed/supported, right? > > And the Questair had one 'on some tubing'. Was this rigid tubing or hose? Seems an installation that would fix the 1-lb sender to the engine mount would work, as long as flexible hose goes in and out of it. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287340#287340 ________________________________________________________________________________
Subject: Re: fuel pressure sender ground
From: "messydeer" <messydeer(at)yahoo.com>
Date: Feb 20, 2010
Thanks, Al :-) I searched the EAA archives and found a few articles by Tony B. about mounting fuel and oil pressure senders. He also recommends mounting the pressure sender to the firewall instead of the engine mount. That would be just as easy for me, if it's better. In these articles (Feb and Mar 1992, I think) he also mentioned putting in custom made pressure reducers in both the oil and fuel lines. Your critique of the fuel pressure sender support makes me wonder about the support of the fuel regulator itself, the ~3" diameter yellow disc shaped object that the T goes into. The pic in my second post shows the Rotec TBI. It's supposedly nearly identical to the Ellison, but has the fuel regulator housed separately from the main unit. The main unit of the TBI has a male AN6 fitting and both ends of the fuel regulator have 1/8" FNPT ports. I have connected the two together with one aluminum AN-NPT adapter fitting. I was planning on supporting this regulator with the Adel clamps as shown in the pic, between the T fitting and engine mount. Maybe this is also a bad idea. If so, I could fasten it instead to the engine with a bracket. You can see two cap screws that hold a plate to the engine mount flange, which is about 4-6" away. I could use the lower cap screw hole to secure a bracket made of 1/8" aluminum. It would go straight to the fuel regulator and fasten through on of its own cap screw holes. The last structural question I have is regarding aluminum vs brass or steel fittings. I'm using aluminum wherever possible. The pics show some brass fittings, but I had planned to replace them with aluminum ones. Would it be better to not use the weaker aluminum for fittings going to the engine? -------- Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287355#287355 Attachments: http://forums.matronics.com//files/restrictor_fittings_by_tony_b_599.jpg http://forums.matronics.com//files/parts_mounted_on_engine_mount_by_tony_b_192.jpg http://forums.matronics.com//files/mounting_fuel_and_oil_pressure_senders_by_tony_b_206.jpg ________________________________________________________________________________
Subject: Re: fuel pressure sender ground
From: "al38kit" <alfranken(at)msn.com>
Date: Feb 20, 2010
I think you're on the right track. Is the thing that looks like a linkage on the regulator just mounted there to control the TBI, or is there a control on the regulator itself...? If the regulator can be mounted elsewhere, consider doing that, perhaps on the firewall or the engine mount and then run the fuel line to the TBI via a flexible line. You could mount the transducer to the regulator, maybe directly and forget about any other fittings....You could then run a dedicated ground wire to the screws on the regulator and solve the transducer grounding thing. Good luck. Al Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287390#287390 ________________________________________________________________________________
Date: Feb 20, 2010
From: Jeff Page <jpx(at)qenesis.com>
Subject: Re: Failure modes with Z14
I received lots of response to this, so rather than copy the text of four messages, I will continue with the pertinent pieces. I appreciate the responses ! To start, I confused everyone, sorry. It is Z14, not Z12 that I am considering (along with Z13/8), so that messed up the discussion a lot, since my actual question was not directly addressed. Also, I didn't mention which electronic ignitions I plan to use. I intend to install E-Mag ignitions, not the Light Speed, but this choice does not really affect the design. I currently fly a 40 year old Cessna. longg@Pjm picked an excellent example, since each spring my wife and I fly it from Toronto to Bahamas to Sun n Fun and back, and other long trips as well. No matter what design I select, it will be a far better system. However, since I can do it better, I want to ;-) Joe described what I like about Z13/8 - pretty much any single electrical failure permits continuation of flight to intended destination. Power from the second alternator can be applied to any chosen load in the airplane as needed, within the limits of the current produced. I have spent quite a lot of times considering the effects of various failures. The only single failure I can think of that would cause a significant problem is an over voltage event that the OV module didn't address in a timely fashion, and the electronics in both ignitions fried. Bob, your experience indicates this is a very unlikely occurance. Medical statistics are the same way. I don't care how rare a disease is if I am the one that has it. Then, in another post, you describe the in-flight fire in a Lancair IV-P due to the abused regulator/OV unit that I am planning on using ;-) An over voltage event is something I have no plan B for. A battery operated radio is great, but there is no equivalent for the ignition. Unlike a regulator and alternator, that I can easily see are working throughout the flight, I have no way of knowing if the OV unit will function as intended in the rare case I need it to. I do not have the resources to analyze and test the design to be convinced it is failure-proof. Of course, like any component, it is not, so I need a plan B. One way of addressing it, is two isolated systems running the ignitions. So although I really like Z13/8, Z14 has possibilities. Unlike Z13/8, Z14 has what seems to me to be a weakness. There is no essential bus diode, so a single contactor failure leaves the battery bus unpowered, in spite of having two working alternators. So if I have one electric fuel pump, and it happens to be on that battery bus, then my flight endurance is limited by battery capacity. Perhaps what I am looking for, is a modification to Z14, that will provide an alternative path to a battery contactor that fails, without providing additional failure modes that take away the advantages of the isolated system. Any ideas how to do this ? Jeff Page Dream Aircraft Tundra #10 ________________________________________________________________________________
Subject: Re: fuel pressure sender ground
From: "messydeer" <messydeer(at)yahoo.com>
Date: Feb 20, 2010
The linkage on the regulator is the primer lever. Pull the cable and it presses down on an a diaphragm override valve allowing fuel to spill into the TBI. So it goes wherever the regulator goes. In case you or anybody has questions or comments about anything in the setup, the fuel line exits the slanted firewall a few inches above the gascolator, which is ~3" in front of the firewall. Then a hose connects into the back of the gascolator. The gascolator, Facet pump, and flow sensor are mounted to the 3 closest engine mount tubes. Two clips supporting the front of the gasco and the fuel flow sensor are not shown. Two brass 1/8-1/4 NPT reducer nipples connect these 3 components. Hose will exit the fuel flow sensor, then up to the mechanical pump (not connected in the pic). > if the regulator can be mounted elsewhere, consider doing that, perhaps on the firewall or the engine mount and then run the fuel line to the TBI via a flexible line. You could mount the transducer to the regulator, maybe directly and forget about any other fittings.... Funny, I just posted a question about using a hose between the regulator and TBI on the Yahoo Jabiru Group. The regulator can be mounted pretty much anywhere else. Rotec says to keep it within a few inches up or down of the TBI. The further backwards it would go, the more of a head change there'd be in a climb or dive, which I guess would mean having to tweak the mixture. Same thing would happen if it were mounted much higher or lower than the intake. The firewall is ~8" behind the intake. I don't know if mounting the regulator on the firewall would be the best. I'll get some more info about that. If it can be done, I'd rather mount both the regulator and the pressure sender on the firewall, cuz that would allow me to use a simple hard fitting between the two components. Then there'd be a single hose to the TBI, but it would mean ~16" of extra hose round trip. >From what TB wrote, it sounds he'd not want the pressure sender anywhere but the firewall. But you'd be okay with it on the engine mount, as long as hose connects it and not hard fittings? -------- Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287399#287399 Attachments: http://forums.matronics.com//files/fuel_pump_plumbing_mockup_side_914.jpg ________________________________________________________________________________
Subject: Re: fuel pressure sender ground
From: "al38kit" <alfranken(at)msn.com>
Date: Feb 20, 2010
I think you'd be fine mounting the regulator and transducer on the engine mount...consider the lower one and maybe you could get by with about a 9" sweeping line to the TB...that way putting a push-pull cable on it would be easy. Good luck... Al Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287432#287432 ________________________________________________________________________________
Date: Feb 20, 2010
From: Ken <klehman(at)albedo.net>
Subject: Re: Failure modes with Z14
Jeff I have 320 hours on my Z-14 which is really two electrical systems. Each system powers an ignition and efi system directly from the battery and either system will run the engine. Both alternators have an OVP system that will disconnect the respective alternator. So to damage one ignition or efi computer there must be two failures. The regulator and then the OVP system. I don't worry about two failures but even then the second system will run the engine. As per Bob's directions for the OVP, it is easy to test the OVP module occasionally if I choose. The procedure is simply to bump the voltage a couple of volts with a couple of D cell flashlight batteries as I recall. I guess my main point is that I do not route engine critical current through a contactor. Why put more things to fail in those current paths. I do run other systems, including starter current through a contactor. The only time the crossfeed contactor closes is during engine cranking or if I decide to manually close it after an alternator fails. I also feed one cigarette lighter receptacle from a battery bus in case I ever need to power a handheld device from it. Also comes in handy when camping. Ken Jeff Page wrote: > > I received lots of response to this, so rather than copy the text of > four messages, I will continue with the pertinent pieces. I appreciate > the responses ! > > To start, I confused everyone, sorry. It is Z14, not Z12 that I am > considering (along with Z13/8), so that messed up the discussion a lot, > since my actual question was not directly addressed. > > Also, I didn't mention which electronic ignitions I plan to use. I > intend to install E-Mag ignitions, not the Light Speed, but this choice > does not really affect the design. > > I currently fly a 40 year old Cessna. longg@Pjm picked an excellent > example, since each spring my wife and I fly it from Toronto to Bahamas > to Sun n Fun and back, and other long trips as well. No matter what > design I select, it will be a far better system. However, since I can > do it better, I want to ;-) > > Joe described what I like about Z13/8 - pretty much any single > electrical failure permits continuation of flight to intended > destination. Power from the second alternator can be applied to any > chosen load in the airplane as needed, within the limits of the current > produced. I have spent quite a lot of times considering the effects of > various failures. > > The only single failure I can think of that would cause a significant > problem is an over voltage event that the OV module didn't address in a > timely fashion, and the electronics in both ignitions fried. Bob, your > experience indicates this is a very unlikely occurance. Medical > statistics are the same way. I don't care how rare a disease is if I am > the one that has it. Then, in another post, you describe the in-flight > fire in a Lancair IV-P due to the abused regulator/OV unit that I am > planning on using ;-) > > An over voltage event is something I have no plan B for. A battery > operated radio is great, but there is no equivalent for the ignition. > Unlike a regulator and alternator, that I can easily see are working > throughout the flight, I have no way of knowing if the OV unit will > function as intended in the rare case I need it to. I do not have the > resources to analyze and test the design to be convinced it is > failure-proof. Of course, like any component, it is not, so I need a > plan B. > > One way of addressing it, is two isolated systems running the > ignitions. So although I really like Z13/8, Z14 has possibilities. > > Unlike Z13/8, Z14 has what seems to me to be a weakness. There is no > essential bus diode, so a single contactor failure leaves the battery > bus unpowered, in spite of having two working alternators. So if I have > one electric fuel pump, and it happens to be on that battery bus, then > my flight endurance is limited by battery capacity. > > Perhaps what I am looking for, is a modification to Z14, that will > provide an alternative path to a battery contactor that fails, without > providing additional failure modes that take away the advantages of the > isolated system. Any ideas how to do this ? > > Jeff Page > Dream Aircraft Tundra #10 > ________________________________________________________________________________
Subject: Re: fuel pressure sender ground
From: "messydeer" <messydeer(at)yahoo.com>
Date: Feb 20, 2010
Good to know. I reread the Rotec advice and they said mounting it level or 2" above would be fine, but don't mount it below the intake, if possible. So I think I've got a good spot on the upper tube. The hose between them is about 4-5" and with maybe 10-15 degrees curve. Now I'll order some more fittings and work on the brackets. Thanks for all your help, Al :-) -------- Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287441#287441 Attachments: http://forums.matronics.com//files/fuel_pressure_and_fuel_regulator_on_upper_mount_long_nipple_156.jpg ________________________________________________________________________________
Date: Feb 21, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Failure modes with Z14
At 03:52 PM 2/20/2010, you wrote: > >The only single failure I can think of that would cause a significant >problem is an over voltage event that the OV module didn't address in >a timely fashion, and the electronics in both ignitions fried. But that's a DUAL failure. An OV protection scheme fails followed by a regulator running amok . . . >Bob, your experience indicates this is a very unlikely occurance. Medical >statistics are the same way. I don't care how rare a disease is if I >am the one that has it. How many dual failures do you intend to hypothesize and address as part of your FMEA? >Then, in another post, you describe the in-flight fire in a Lancair >IV-P due to the abused regulator/OV unit that I am planning on using ;-) That wasn't an electronics failure but an INSTALLATION failure. Similarly, you can't have a plan-b for loose prop bolts, thrown jugs, ailerons lost to high speed flutter, etc. These things are even more rare but offer exceedingly dire challenges to your survival skills. >An over voltage event is something I have no plan B for. A optimally managed OV event becomes an LV even in tens of milliseconds after onset of the failure. This is why we generally don't bother to install OV annunciators on the panel . . . but bulbs don't stay lit long enough for you to make much use of what they have to tell you. After the alternator is shut down, plan-b is the same as if you'd thrown a belt, broken a wire, etc. >A battery operated radio is great, but there is no equivalent for >the ignition. >Unlike a regulator and alternator, that I can easily see are working >throughout the flight, I have no way of knowing if the OV unit will >function as intended in the rare case I need it to. I do not have the >resources to analyze and test the design to be convinced it is >failure-proof. Of course, like any component, it is not, so I need a >plan B. This is why instructions for installing our OV modules call for testing every annual along with instructions on how to do it. However, these devices have been installed on TC aircraft for over 40 years. I don't recall seeing any maintenance manual call for annual testing. >One way of addressing it, is two isolated systems running the >ignitions. So although I really like Z13/8, Z14 has possibilities. >Unlike Z13/8, Z14 has what seems to me to be a weakness. There is no >essential bus diode, so a single contactor failure leaves the battery >bus unpowered, in spite of having two working alternators. So if I >have one electric fuel pump, and it happens to be on that battery bus, >then my flight endurance is limited by battery capacity. If a fuel pump is critical to sustained flight, then why don't you have two pumps? Z14 has no ENDURANCE bus because one bus becomes the endurance bus should the other one be taken down due to alternator failure. If the small alternator quits, then most likely both busses can be kept up using the larger alternator. If the big guy quits, then shut the main bus down, reduce loads to get airport in sight using small alternator . . . then close the cross-feed contactor and use both batteries plus small alternator to terminate the flight. >Perhaps what I am looking for, is a modification to Z14, that will >provide an alternative path to a battery contactor that fails, without >providing additional failure modes that take away the advantages of >the isolated system. Any ideas how to do this ? Your stacking failure on top of failure to the degree that you'll have plans B, C, D, etc. Worse yet, you risk becoming and electrical systems failure analyst when you should be concentrating on piloting instead of deducing the appropriate "plan". Make one of the Emags a self-powered version and wire as shown in Figure Z-13/8 . . . you've got redundancy to burn. If your engine is electrically dependent on fuel delivery, then you need two pumps. Run one from the main bus, the other from the battery bus. Run a 9011 multi-channel OV.LV monitor to annunciate contactor failure. Bob . . . ________________________________________________________________________________
Date: Feb 21, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Next generation of OBAM aircraft?
A recent development in gps aided stability and position holding not to mention energy management. http://vimeo.com/6194911 Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ ________________________________________________________________________________
Date: Feb 21, 2010
From: Robert Reed <robertr237(at)att.net>
Subject: Re: Next generation of OBAM aircraft?
I would love to get one of those to play with and a dozen or so for busines s.- Sure would be a lot cheaper method of doing aerial photography among other things.- I can see a business in the making.=0A=0A-=0A=0A=0A=0A__ ______________________________=0AFrom: "Robert L. Nuckolls, III" <nuckolls. bob(at)aeroelectric.com>=0ATo: aeroelectric-list(at)matronics.com=0ASent: Sun, Fe bruary 21, 2010 11:54:48 AM=0ASubject: AeroElectric-List: Next generation o uckolls, III" =0A=0AA recent development in gps aided stability and position=0Aholding not to mention energy management .=0A=0A=0Ahttp://vimeo.com/6194911=0A=0A=0A- Bob . . .=0A=0A- - - - - - - - - ////=0A- - - - - - - - - (o o)=0A - ===========o00o=(_)=o00o======= ===0A- < Go ahead, make my day . . .- >=0A- < show me where I'm w rong.- - - >=0A- ================ ============ ________________________________________________________________________________
Subject: notes on Z Drawings
From: "falconarf12a" <buzzleo(at)graceba.net>
Date: Feb 21, 2010
How can I access the notes the are reference on the Z drawings? [Question] -------- SEL Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287514#287514 ________________________________________________________________________________
From: "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net>
Subject: notes on Z Drawings
Date: Feb 21, 2010
How can I access the notes the are reference on the Z drawings? [Question] -------- SEL The notes are listed in this section. http://www.aeroelectric.com/R12A/AppZ_12A4.pdf Roger ________________________________________________________________________________
Date: Feb 21, 2010
Subject: Stick drawing for warning lights
From: rparigor(at)suffolk.lib.ny.us
I have a Europa monowheel with Rotax 914. Do have a Dynon D-10A piece of glass but engine and other instruments are analogue. I was thinking it would be neat to have a sketch/stick drawing of aeroplane missing aft section and have lights to indicate status or warnings. I have a 6" x 6" piece of real estateto work with on ceilingbegining a few inches aft of windscreen with conduits installed to run plumb in electron flow. Has anyone done something like thisr? Any pictures? Ideas, opinions and detailswelcomed. Ron Parigoris ________________________________________________________________________________
Subject: Re: notes on Z Drawings
From: "falconarf12a" <buzzleo(at)graceba.net>
Date: Feb 21, 2010
This link doesn't work for me......is it correct? http://www.aeroelectric.com/R12A/AppZ_12A4.pdf -------- SEL Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287539#287539 ________________________________________________________________________________
Subject: Re: notes on Z Drawings
From: "falconarf12a" <buzzleo(at)graceba.net>
Date: Feb 21, 2010
OK never mind I got it to work!!!!! Thanks -------- SEL Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287544#287544 ________________________________________________________________________________
From: "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net>
Subject: Re: notes on Z Drawings
Date: Feb 21, 2010
This link doesn't work for me......is it correct? http://www.aeroelectric.com/R12A/AppZ_12A4.pdf It works fine for me. Try www.aeroelectric.com > click on "Whats New" > go to Rev 12A Appendix Z Power distribution drawings. The notes are toward the end of the text portion, just prior to the drawings. Roger Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287539#287539 ________________________________________________________________________________
Date: Feb 22, 2010
From: Jeff Page <jpx(at)qenesis.com>
Subject: Re: Failure Modes with Z14
> I guess my main point is that I do not route engine critical current > through a contactor. Why put more things to fail in those current paths. > I do run other systems, including starter current through a contactor. Yes, I intend to power the ignitions and fuel pump directly from the battery bus (through fuses of course). > The only time the crossfeed contactor closes is during engine cranking > or if I decide to manually close it after an alternator fails. I also > feed one cigarette lighter receptacle from a battery bus in case I ever > need to power a handheld device from it. Also comes in handy when camping. I re-wired the cigarette lighter in my Cessna so I could charge my phone at Sun n fun and Oshkosh :-) > Ken >> The only single failure I can think of that would cause a significant >> problem is an over voltage event that the OV module didn't address in >> a timely fashion, and the electronics in both ignitions fried. > > But that's a DUAL failure. An OV protection scheme fails > followed by a regulator running amok . . . > How many dual failures do you intend to hypothesize and > address as part of your FMEA? Failure of any single part should cause little concern, and probably little notice by an oblivious passenger. Probably most dual failures would mean full utilization of plan B, rather than a forced landing. The dual failure that merits my attention is both ignitions failing. With isolated electrical systems, that would be exceptionally unlikely. With Z13/8 and a B&C LR3C-14 (or equivalent), that could potentially happen. I don't plan on mounting it upside down so it can fill with water, but it is not impossible that I unknowingly make a similar mistake. In the event of an OV situation, I have to count on the controller and the circuit breaker both doing what they are supposed to do. Most of us have much confidence due to familiarity in the electrical items like alternators installed on our planes, because we have used them in cars etc. for years and have monitored their operation. And we know they fail sometimes. Who hasn't replaced an alternator ? At best we can occasionally test the OV circuitry. How many of us have extensive experience with the OV protection accomplishing its mission when it was needed ? How do I compare the sensitivity of the OV module compared to the ignition module ? If I install isolated systems to run the ignitions, I do not need to determine the potential for failure of the regulator, OV circuitry and circuit breaker. I know it seems like I am overly concerned about a very unlikely possibility. As ugly and maintenance prone as magentos are, they are unbelievably unlikely to both fail on the same flight. I don't want to replace them with another system, for which I can identify a possible failure mode that takes them both out, while addressing it only with "well, that is very unlikely". I need to either modify the design to eliminate the possibility, or be convinced that very unlikely is much more unlikely than, say, my prop coming off. I have no practical way of quantifying "very unlikely", so I am trying to eliminate the possibility. An isolated system is not excessively complex or expensive, I just need to determine the best way to do it. >> Then, in another post, you describe the in-flight fire in a Lancair >> IV-P due to the abused regulator/OV unit that I am planning on using ;-) > That wasn't an electronics failure but an INSTALLATION failure. Hopefully, due to the time spent learning from your book and this list (much appreciated !), together with my schooling and attention to detail, I won't make a similar error. > Similarly, you can't have a plan-b for loose prop bolts, thrown > jugs, ailerons lost to high speed flutter, etc. These things > are even more rare but offer exceedingly dire challenges to > your survival skills. The best I can do to mitigate some of these risks is to purchase quality parts and assemble them with mentors and mechanics checking my work, plus dual instruction in handling emergencies. >> An over voltage event is something I have no plan B for. > A optimally managed OV event becomes an LV even in tens > of milliseconds after onset of the failure. This is why > we generally don't bother to install OV annunciators > on the panel . . . but bulbs don't stay lit long enough > for you to make much use of what they have to tell you. > After the alternator is shut down, plan-b is the same > as if you'd thrown a belt, broken a wire, etc. As long as my ignitions are still working, plan B works well, otherwise I am landing in a very undesirable place :-( >> One way of addressing it, is two isolated systems running the >> ignitions. So although I really like Z13/8, Z14 has possibilities. >> Unlike Z13/8, Z14 has what seems to me to be a weakness. There is no >> essential bus diode, so a single contactor failure leaves the battery >> bus unpowered, in spite of having two working alternators. So if I >> have one electric fuel pump, and it happens to be on that battery bus, >> then my flight endurance is limited by battery capacity. > > If a fuel pump is critical to sustained flight, then why > don't you have two pumps? Z14 has no ENDURANCE bus because > one bus becomes the endurance bus should the other one be > taken down due to alternator failure. If the small alternator > quits, then most likely both busses can be kept up using > the larger alternator. If the big guy quits, then shut > the main bus down, reduce loads to get airport in sight using > small alternator . . . then close the cross-feed contactor > and use both batteries plus small alternator to terminate > the flight. The electric fuel pump is only necessary to back up the mechanical pump. It just seems odd that with the design of Z14, that with the single failure of a contactor, but two working alternators, there is no path to charge both batteries. With Z13/8 there are dual charging paths, which is a very nice design. > Make one of the Emags a self-powered version and wire > as shown in Figure Z-13/8 . . . you've got redundancy > to burn. Actually, I do intend to run one or two P-Mags. I just need to ensure I will not fry both of them with an OV event. > Run a 9011 multi-channel OV.LV monitor to annunciate > contactor failure. I have designed, but not yet prototyped a LV monitor that will annunicate LV on either battery, and be activated by either battery contactor switch or the "clearance delivery" switch (the don't drain the battery by leaving the switch on idiot feature). Some of the features of Z14 I probably don't need. There has been some discussion that two smaller batteries cannot delivery the same starter current that a single large battery can. Perhaps the solution is a modification to Z13/8, whereby the standby alternator is always in use to power the second ignition. Isolate that with a cross feed relay and add a second small battery. The cross feed relay would be only used to route power to the endurance bus after main alternator failure, but not to kick in the second battery during starting. Jeff Page Dream Aircraft Tundra #10 ________________________________________________________________________________
Subject: Strobe power ground?
From: "jayb" <jaybrinkmeyer(at)yahoo.com>
Date: Feb 22, 2010
I have a Wheelen strobe power pack in the back of an RV-10. My forest of tabs ground is on the firewall. Should I pull the power pack ground forward or just ground locally? I can't think of a good reason the strobe would be a ground loop victim. Thanks in advance for your reply. Jay Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287606#287606 ________________________________________________________________________________
Subject: Re: Next generation of OBAM aircraft?
From: "sonex293" <sonex293(at)gmail.com>
Date: Feb 22, 2010
Kits are available... http://www.mikrokopter.de/ -- MC -------- Michael Crowder Jabiru 3300A w/ Hyd Lifters AeroCarb w/ #3 needle Sonex N293SX Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287607#287607 ________________________________________________________________________________
From: "Carlos Trigo" <trigo(at)mail.telepac.pt>
Subject: Re: Next generation of OBAM aircraft?
Date: Feb 22, 2010
There is also a Portuguese small Tech company doing a similar bird, which I know has already sold some of these aero-robots to the Military, some Fire Department, the Homeland Security.Dept and the Agricultural Department. See http://www.uavision.com/aeronautics/ Carlos > -----Original Message----- > From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list- > server(at)matronics.com] On Behalf Of sonex293 > Sent: segunda-feira, 22 de Fevereiro de 2010 12:48 > To: aeroelectric-list(at)matronics.com > Subject: AeroElectric-List: Re: Next generation of OBAM aircraft? > > > Kits are available... > > http://www.mikrokopter.de/ > > -- > MC > > -------- > Michael Crowder > Jabiru 3300A w/ Hyd Lifters > AeroCarb w/ #3 needle > Sonex N293SX > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=287607#287607 > > > > > > > > > ________________________________________________________________________________
Subject: RFC: My external power schematic
From: "mouser" <mouser(at)mouser.org>
Date: Feb 22, 2010
I'm about to add in the external power connector to my RV-10 project and I'd like to get some feedback on my schematic before I implement it. The idea is to have a small door in the baggage bulkhead which gives access to the standard 3-pin connector, a LED which indicates contactor status, and a switch that gives some control over how the contactor behaves. The switch will have three positions: FORCE: The external power contactor is held closed by the main aircraft battery. AUTO: The external power contactor is actuated by the signal on the third (small) pin in the connector. INHIBIT: The external power contactor will not close, regardless of the signal on the connector. The LED next to the switch indicates the contactor status. I think in my installation the switch and LED will be mounted adjacent to the connector, as I won't likely need to change the external power contactor behavior while sitting up front. The only problem with this setup is that when the switch is set to "FORCE," the LED is always on. So if I walk away and forget about that, it's a slow drain on the main battery. I've attached the schematic I'm currently considering. Comments? Advice? Thanks, -Richard RV-10 #40988 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287612#287612 Attachments: http://forums.matronics.com//files/external_power_schematic_208.png ________________________________________________________________________________
Subject: Re: Stick drawing for warning lights
From: "Eric M. Jones" <emjones(at)charter.net>
Date: Feb 22, 2010
Ron, If I get what you're asking for--there are already symbols for every type of condition published by ISO. Just Google ISO symbols.... If you have been driven crazy by the ISO symbols already, you can make up your own using ISO-symbol protocols. Yes, it's a bit much, but it's the only game in town now. And don't forget the warning for "My God...Don't touch that button!" "Hell, there are no rules here , we're trying to accomplish something." --Thomas Edison -------- 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=287614#287614 ________________________________________________________________________________
Date: Feb 22, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Strobe power ground?
At 06:40 AM 2/22/2010, you wrote: > >I have a Wheelen strobe power pack in the back of an RV-10. My >forest of tabs ground is on the firewall. Should I pull the power >pack ground forward or just ground locally? I can't think of a good >reason the strobe would be a ground loop victim. > >Thanks in advance for your reply. See illustrations in Figure Z15. Bob . . . ________________________________________________________________________________
Date: Feb 22, 2010
From: David <ainut(at)knology.net>
Subject: Re: Next generation of OBAM aircraft?
________________________________________________________________________________
Date: Feb 22, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: RFC: My external power schematic
At 07:27 AM 2/22/2010, you wrote: > > >I've attached the schematic I'm currently considering. How would you use these features? What are the conditions that make them useful? Keep in mind too that a crow-bar ov module MUST be paired with a 2-5A breaker or breaker switch capable of co-existing with this technology. I.e. high interrupt current ratings. Commercial breakers are suspect. See: http://aeroelectric.com/Pictures/Breakers/Breaker_Failure_1a.jpg Miniature breakers popular with aviation are quite happy working this task: http://aeroelectric.com/Pictures/Breakers/Klixon_1.jpg Let's discuss the ways in which the schematic in Z-31A falls short of your design goals. Bob . . . ________________________________________________________________________________
Date: Feb 22, 2010
From: Jeff Page <jpx(at)qenesis.com>
Subject: Re: Next Generation of OBAM aircraft
> From: Robert Reed <robertr237(at)att.net> > Subject: Re: AeroElectric-List: Next generation of OBAM aircraft? > > I would love to get one of those to play with and a dozen or so for busines > s.- Sure would be a lot cheaper method of doing aerial photography among > other things.- I can see a business in the making I had the same thought. The kits are in the $2000 range. There are a few distributors located around the world. http://www.mikrokopter.de/ucwiki Jeff Page Dream Aircraft Tundra #10 ________________________________________________________________________________
Subject: Re: Failure modes with Z14
From: "user9253" <fran4sew(at)banyanol.com>
Date: Feb 22, 2010
The battery is NOT the power source for electrical equipment on an aircraft. The alternator is. Z-13/8 has two alternators. If the main one fails, the aux alternator will power the ignition. If both alternators fail, the battery is a backup. Once the engine is running, failure of the battery contactor will most likely not affect the operation of the alternators. An ignition connected to the E-bus will keep working after the battery contactor fails, drawing its power from the alternator as usual. Each ignition should be connected to separate points of the electrical system so that a bad connection will only affect one ignition. In Z-13/8 after a battery contactor failure, the battery can be kept charged by the main alternator through the E-Bus relay or by the aux alternator. Even if both alternators and the battery contactor fail, the battery still has enough stored energy to power one ignition for a couple of hours. The length of time can be determined by doing a load test on the battery. This is something that should be done periodically anyway. If there are still concerns of contactor failure, a diode can be placed across the big terminals of the contactor with the arrow pointing towards the battery. However, this is not needed or recommended. Many years ago I had a VW with a 6 volt battery. The generator quit working (but I did not know it). The engine barely cranked when I started it to go home after work at night. After a couple of miles, the headlights got dimmer and dimmer, then the engine quit. Before the car coasted to a stop, I shut off the headlights and the engine started to run again. There was not much traffic that late at night. Every time a car approached, I pulled off onto the shoulder and waited for it to go by. It was hard to see without headlights. I discovered that the engine would keep running with the turn signal on. So I used that to see the road, driving very slowly. It took me a couple of hours to get home, but I made it. The point is that it doesn't take a fully charged battery to power the ignition. As for over voltage protection, two OV modules can be used. Then the regulator would have to fail along with both OV modules before the electronics would be fried. I do not think these extreme measures are necessary or desired. If the voltage regulator fails, an alternator properly sized to just barely meet the expected load will not develop as high of a voltage as a larger alternator will. Many things can go wrong on an aircraft. Perhaps a BRS is the answer. But even those malfunction. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287634#287634 ________________________________________________________________________________
Date: Feb 22, 2010
From: Ken <klehman(at)albedo.net>
Subject: Re: Failure Modes with Z14
Jeff The 2 little Dekka 8 AH batteries on my Z-14 system are indeed equivalent to one 16AH battery except for being more expensive. They have large bolted lead terminals and one will start the subaru. Two are better when it is very cold. The batteries do what the manufacturer says. Small batteries with small terminals that are not designed to start engines will be a different story. My system does indeed allow charging both batteries with any single contactor failure. Not a big deal but a consideration with small batteries. Both alternators feed through their OV contactors to the respective battery. No second contactor between them and the batteries. With appropriate component placement I believe that I have no additional always hot wiring risk with this setup. Because I feed non engine loads (and cranking current) through a contactor, a failure of that contactor will kill most other systems but it won't affect the engine. I have ample battery bus (the cigarette lighter and limited panel lighting), and handheld backup options for that. I do not have any IFR avionics at this time. Your failure concerns do resonate with me. My design was heavily influenced by the knowledge that it was a one off system by a first time builder using components placed in a new environment that nullified previous failure data. That is why Bob's philosophy and Z-14 suited me so well with an electric dependent engine. Even though electric components can fail without warning, the engine electrical and EFI systems are the least of my engine reliability concerns now. If it helps - yes I did spend some time testing the OV modules and yes they perform exactly as advertised and the current version simply does not trip unless there is a real OV event. Don't overlook ergonomics. Keep your system as operationally simple as possible. Give some thought to what you actions you will take for failures and locate controls to make those actions simple and methodical. Ideally one procedure for all engine problems is ideal. Ken snip> > Some of the features of Z14 I probably don't need. There has been some > discussion that two smaller batteries cannot delivery the same starter > current that a single large battery can. Perhaps the solution is a > modification to Z13/8, whereby the standby alternator is always in use > to power the second ignition. Isolate that with a cross feed relay and > add a second small battery. The cross feed relay would be only used to > route power to the endurance bus after main alternator failure, but not > to kick in the second battery during starting. > > Jeff Page > Dream Aircraft Tundra #10 > > > > > ________________________________________________________________________________
Subject: External Power Options
Date: Feb 22, 2010
From: <longg(at)pjm.com>
I don't know what everyone is using but I definitely don't want the lead anchor plug and related equipment I had on My Cherokee. I don't want the Cessna variety either. These days you're hard pressed to find support for either after business hours. Finding a 110 plug is much more feasible. Couldn't I just use two of the below recessed into my cowling/fuselage and connect them directly to the battery +/-? In that way I can just connect my charger and receive the same benefit. http://www.pegasusautoracing.com/productdetails.asp?RecID=2848 ________________________________________________________________________________
Subject: Re: RFC: My external power schematic
From: "mouser" <mouser(at)mouser.org>
Date: Feb 22, 2010
nuckolls.bob(at)aeroelect wrote: > > Let's discuss the ways in which the schematic in > Z-31A falls short of your design goals. > First, the minor differences: I put an LED across the solenoid so that I have some immediate feedback that it is engaged when I think it should be (and not engaged when I think it shouldn't be). Ran into a problem with this at work one day with a Twin Otter sitting on the ramp plugged into a generator but the small pin wasn't connected properly within the plug and never engaged the solenoid. I had no feedback that this was the case, the ramp was too noisy to hear the solenoid click, and didn't have direct access to the solenoid to DVM the contacts. Drained the main batteries (and a fair amount of fuel out of the generator for no reason) without realizing it. I also added a second diode reversed across the solenoid, similar to the one you have across the main battery contactor in Z-31A. Is there something different about the external power contactor that makes this safety not recommended? I do need to add the circuit breaker as you recommend, that was an oversight. The major departure in my schematic is the addition of the switch. The center position gives the same behavior as Z-31A. The "force" position I put in there as a means of overcoming the problem I saw with the Otter. If I am presented with a power supply whose third pin is not engaging the contactor, I can force it closed manually. The "inhibit" position I don't have a specific operational need for, but it came at a cost of zero complexity (the DP3T switch is internally more complex than a SPDT, I suppose... but there are no extra wires or parts). I think the only time it would see use is if I found myself in a position of troubleshooting something and wanted to repeatedly add and remove ground power with minimal physical effort. With any luck, I'd just leave the switch on Auto for the lifetime of the airplane. But weird stuff happens... :) Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287643#287643 ________________________________________________________________________________
Date: Feb 22, 2010
From: Ken <klehman(at)albedo.net>
Subject: Re: Failure modes with Z14
While I have also seen an electrical system function just fine with the battery disconnected, such performance is not a certainty in all situations. You raise a point that is dear to me though. Perhaps because I've seen the results of batteries fed by a runaway regulator, I am also a proponent of using a small alternator. ie. one that is adequate for normal ops rather than one that can put out twice the power that will ever be needed. Especially as we migrate to lower power electronics, lights, and smaller batteries. Years ago I also had an occasion to manually cycle a runaway generator with a melting battery while IFR and it would have been much less tense had it been a smaller unit. I have confidence in the OV protection but my OV contactor still has to open for it to work and the less current going through it the better I think. Actually I had a different contactor fail to open this weekend but it worked on about 20 subsequent tries so I don't know yet whether it is the switch or the contactor. My OV contactors normally switch while unloaded so they will likely last forever. Ken user9253 wrote: > > > The battery is NOT the power source for electrical equipment on an > aircraft. The alternator is. Z-13/8 has two alternators. If the > main one fails, the aux alternator will power the ignition. If both > alternators fail, the battery is a backup. Once the engine is > running, failure of the battery contactor will most likely not affect > the operation of the alternators. An ignition connected to the E-bus > will keep working after the battery contactor fails, drawing its > power from the alternator as usual. Each ignition should be > connected to separate points of the electrical system so that a bad > connection will only affect one ignition. In Z-13/8 after a battery > contactor failure, the battery can be kept charged by the main > alternator through the E-Bus relay or by the aux alternator. Even if > both alternators and the battery contactor fail, the battery still > has enough stored energy to power one ignition for a couple of hours. > The length of time can be determined by doing a l! oad test on the > battery. This is something that should be done periodically anyway. > If there are still concerns of contactor failure, a diode can be > placed across the big terminals of the contactor with the arrow > pointing towards the battery. However, this is not needed or > recommended. Many years ago I had a VW with a 6 volt battery. The > generator quit working (but I did not know it). The engine barely > cranked when I started it to go home after work at night. After a > couple of miles, the headlights got dimmer and dimmer, then the > engine quit. Before the car coasted to a stop, I shut off the > headlights and the engine started to run again. There was not much > traffic that late at night. Every time a car approached, I pulled > off onto the shoulder and waited for it to go by. It was hard to see > without headlights. I discovered that the engine would keep running > with the turn signal on. So I used that to see the road, driving > very slowly. It took me a couple of hours to get home, but I made > it. The point is that it doesn't take a fully charged battery to > power the ignition. As for over voltage protection, two OV modules > can be used. Then the regulator would have to fail along with both > OV modules before the electronics would be fried. I do not think > these extreme measures are necessary or desired. If the voltage > regulator fails, an alternator properly sized to just barely meet the > expected load will not develop as high of a voltage as a larger > alternator will. Many things can go wrong on an aircraft. Perhaps a > BRS is the answer. But even those malfunction. Joe > > -------- Joe Gores > > ________________________________________________________________________________
Subject: Re: Strobe power ground?
From: "johngoodman" <johngoodman(at)earthlink.net>
Date: Feb 22, 2010
I think that Bob is saying you can ground it to the airframe or the forest of tabs. It brings up another question concerning aluminum RVs. If the forest of tabs is on the stainless steel firewall and the engine is grounded to it, shouldn't the forest of tabs be linked to some nearby aluminum for better grounding? I think a braided line has been suggested, but a wire back to the actual main battery ground would also work - but how big? A #2awg is impractical. Would somethings as small as a #10awg be good enough, since it's all still attached to the airframe? John -------- #40572 QB. Engine on, wing attach coming soon. Panel delivery soon. N711JG reserved Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287678#287678 ________________________________________________________________________________
Date: Feb 22, 2010
From: Bill Mauledriver Watson <MauleDriver(at)nc.rr.com>
Subject: Re: Next generation of OBAM aircraft?
The next gen of OBAM aircraft? It reminds me that we are probably in the golden age of OBAMA and personal GA (no pun intended). Just reverse this scenario http://alturl.com/gmqu As unmanned and unpiloted aircraft hit their stride, those unpredictable piloted aircraft with their free thinking, and at times, malevolent pilots are going to be increasingly pushed into airspace restricted to non-commercial, non-military, no-ATC-services areas. Probably to be called 'uncontrolled' airspace... and we know how rare that has become. Makes one savor the ability to hand fly our hand built aircraft from coast to coast, all within the system. Neat link. Thanks. Bill "breaking at 4:30 to do the windscreen lay-up" Watson sonex293 wrote: > > Kits are available... > > http://www.mikrokopter.de/ > > -- > MC > > -------- > Michael Crowder > Jabiru 3300A w/ Hyd Lifters > AeroCarb w/ #3 needle > Sonex N293SX > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=287607#287607 > > > ________________________________________________________________________________
Date: Feb 22, 2010
From: Peter Pengilly <peter(at)sportingaero.com>
Subject: Re: Strobe power ground?
Let's think about what is going on here for a moment. The idea is to allow the current to flow back to the alternator/battery without much impediment (and without inducing ground loops in sensitive audio circuits). The firewall is riveted to the rest of the fuselage with perhaps hundreds of rivets, each clamping the components tightly together. The forest of tabs has a large brass nut on it to which the battery earth strap is connected. All the frames in the fuselage are riveted to the skin and the longerons with 10s of rivets. Installing an earth stud (that makes good contact with the metal) on a frame near to the strobe power supply, and hooking the power supply up to it with a #18 wire, will complete the circuit and achieve the desired aim with minimum weight. Sure you can run a #10 (or #18) wire back to the forest of tabs, but its completely redundant. Peter johngoodman wrote: > > I think that Bob is saying you can ground it to the airframe or the forest of tabs. It brings up another question concerning aluminum RVs. If the forest of tabs is on the stainless steel firewall and the engine is grounded to it, shouldn't the forest of tabs be linked to some nearby aluminum for better grounding? > I think a braided line has been suggested, but a wire back to the actual main battery ground would also work - but how big? A #2awg is impractical. Would somethings as small as a #10awg be good enough, since it's all still attached to the airframe? > John > > -------- > #40572 QB. Engine on, wing attach coming soon. Panel delivery soon. > N711JG reserved > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=287678#287678 > > > ________________________________________________________________________________
Subject: Re: Strobe power ground?
From: "johngoodman" <johngoodman(at)earthlink.net>
Date: Feb 22, 2010
Peter is right, but I do think Bob suggested some kind of supplemental grounding if the forest of tabs is on the stainless steel firewall. John -------- #40572 QB. Engine on, wing attach coming soon. Panel delivery soon. N711JG reserved Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287695#287695 ________________________________________________________________________________
Date: Feb 22, 2010
From: Bill Mauledriver Watson <MauleDriver(at)nc.rr.com>
Subject: Re: Strobe power ground?
I have no idea whether it is acceptable - but I have a #8 running from my batteries to the forest of tabs on the firewall with the thought that the tab is grounded to the airframe and directly. Feel good about it and think I discussed it with Bob here sometime ago. Bill johngoodman wrote: > > I think that Bob is saying you can ground it to the airframe or the forest of tabs. It brings up another question concerning aluminum RVs. If the forest of tabs is on the stainless steel firewall and the engine is grounded to it, shouldn't the forest of tabs be linked to some nearby aluminum for better grounding? > I think a braided line has been suggested, but a wire back to the actual main battery ground would also work - but how big? A #2awg is impractical. Would somethings as small as a #10awg be good enough, since it's all still attached to the airframe? > John > > -------- > #40572 QB. Engine on, wing attach coming soon. Panel delivery soon. > N711JG reserved > > > ________________________________________________________________________________
Subject: Loss of LR3C compared to switcher
From: "rparigoris" <rparigor(at)suffolk.lib.ny.us>
Date: Feb 23, 2010
Curiosity question, according to B+C a SD20S alternator turning when hot at 2500RPM it will produce 24 amps at 14V, how much approximate loss will there be using a LR3C regulator? How much approx. loss using a switcher? Same question for SD20S at 2000RPM, 15 amp output at 14V? Thx. Ron Parigoris Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287768#287768 ________________________________________________________________________________
Subject: Re: RFC: My external power schematic
From: "user9253" <fran4sew(at)banyanol.com>
Date: Feb 23, 2010
The whole purpose of having a diode and relay is to prevent a reversed polarity connection between the aircraft and external power. The switch in the forced position defeats that safety feature, putting expensive avionics at risk along with a potential for fire or exploding batteries. Compare those risks to the inconvenience of the 3d pin not making contact in Z-31A. It isn't just inexperienced line-boys who connect batteries backwards. Qualified people who are complacent or preoccupied make mistakes too. Dwg Z-31B eliminates the 3d pin. Or how about modifying your circuit to use external power through a diode to power the relay like this: http://tinyurl.com/ylbabzd Here is a discussion about plugs and sockets if you have not purchased them yet: http://forums.matronics.com/viewtopic.php?t=68440&sid=19d878ba84382f9b62db3fdf8411436f Here is a link to plugs and sockets for sale: http://www.ryderfleetproducts.com/cgi-bin/ryderfp/products/srm/oid/51817/pn/Single-Pole-Socket-Female/erm/product_detail.jsp -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287808#287808 ________________________________________________________________________________
Date: Feb 23, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Loss of LR3C compared to switcher
At 02:11 AM 2/23/2010, you wrote: > > >Curiosity question, according to B+C a SD20S alternator turning when >hot at 2500RPM it will produce 24 amps at 14V, how much approximate >loss will there be using a LR3C regulator? How much approx. loss >using a switcher? > >Same question for SD20S at 2000RPM, 15 amp output at 14V? No difference. The regulator's influence on max current available is minimal. The alternators driven from a vacuum pump pad are RPM limited. Bob . . . ________________________________________________________________________________
Date: Feb 23, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Failure Modes with Z14
At 09:38 AM 2/22/2010, you wrote: > >Jeff > >The 2 little Dekka 8 AH batteries on my Z-14 system are indeed >equivalent to one 16AH battery except for being more expensive. They >have large bolted lead terminals and one will start the subaru. Two >are better when it is very cold. The batteries do what the >manufacturer says. Small batteries with small terminals that are not >designed to start engines will be a different story. Yes, the Dekka products are unique for their size. >My system does indeed allow charging both batteries with any single >contactor failure. Not a big deal but a consideration with small >batteries. Both alternators feed through their OV contactors to the >respective battery. No second contactor between them and the batteries. Your words generate an interesting idea . . . Assume the builder chooses commercial off the shelf IR alternators and a variant on Z-24 for control and ov protection. In this instance, one COULD set the altenrator b-lead contactor next to a battery contactor and tie it's output directly to the battery. This configuration satisfies the legacy design goal of minimizing hot fat-wires when all switches are OFF. Now you can have your battery contactors feed a single main bus. No e-bus is needed since you're not likely to every need battery-only ops. Now you have two, independently alternator-supported batteries. Two battery busses to distribute loads for an electrically dependent engine. A main bus that's not subject to single-point-of-failure. Cool. I'll pray over this a bit. Perhaps a Figure Z-8 is being conceived . . . Bob . . . ________________________________________________________________________________
Date: Feb 23, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: External Power Options
At 09:43 AM 2/22/2010, you wrote: > >I don't know what everyone is using but I definitely don't want the lead >anchor plug and related equipment I had on My Cherokee. I don't want the >Cessna variety either. These days you're hard pressed to find support >for either after business hours. Finding a 110 plug is much more >feasible. > >Couldn't I just use two of the below recessed into my cowling/fuselage >and connect them directly to the battery +/-? > >In that way I can just connect my charger and receive the same benefit. > > >http://www.pegasusautoracing.com/productdetails.asp?RecID=2848 The Piper-Style ground power connector is light and low cost . . . an readily serviced by folks who are truly in FBO business. Further, you can fabricate your own set of jumper cables with the mating connector on one end and carry it in the a/c for use when only a car or portable battery is available for support. I don't think I'd want hi-fault current terminals hanging out just to support and exceedingly rare need for ground power. In 20+ years I've only be to the FBO twice to get ground power support. And that was with weather conditions that I would much rather not have been flying in (-10F). For 99.9% of your flying, ground power support is just dead weight. If your proposed missions put you at higher risk for needing ground power, then some robust, universally installed architecture will probably serve you best. Bob . . . P.S. those plastic firewall feed-throughs are NOT firewall rated just in case anyone is thinking they might use those elsewhere . . . ________________________________________________________________________________
Date: Feb 23, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Strobe power ground?
At 01:32 PM 2/22/2010, you wrote: > > >I think that Bob is saying you can ground it to the airframe or the >forest of tabs. It brings up another question concerning aluminum >RVs. If the forest of tabs is on the stainless steel firewall and >the engine is grounded to it, shouldn't the forest of tabs be linked >to some nearby aluminum for better grounding? Not necessary. The only currents carried on the firewall sheet are those few items locally grounded as shown on http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/Z15K3p1.pdf >I think a braided line has been suggested, but a wire back to the >actual main battery ground would also work - but how big? A #2awg is >impractical. Would somethings as small as a #10awg be good enough, >since it's all still attached to the airframe? No added value. If you do a micro-ohmmeter check between the firewall ground block and major aluminum airframe structure, it will be hundreds of micro-ohms. Bob . . . ________________________________________________________________________________
Date: Feb 23, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Strobe power ground?
At 02:29 PM 2/22/2010, you wrote: > > >I have no idea whether it is acceptable - but I have a #8 running >from my batteries to the forest of tabs on the firewall with the >thought that the tab is grounded to the airframe and directly. Feel >good about it and think I discussed it with Bob here sometime ago. ???? Did I recommend this . . . or just offer that it didn't hurt anything ??? Bob . . . ________________________________________________________________________________
Date: Feb 23, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Strobe power ground?
At 05:18 PM 2/22/2010, you wrote: > > >Peter is right, but I do think Bob suggested some kind of >supplemental grounding if the forest of tabs is on the stainless >steel firewall. Hmmmm . . . I'll need to search the archives on that. I wonder if I was smoking something really good that night. I can't imagine the thought processes that would have made a redundant ground attractive. I do seem to recall some folks wondering if they could ground tail mounted batteries locally . . . or does the system work better if battery ground is brought forward on it's own wire. Upon further reflection, we've been grounding batteries in the tail on metal airplanes for a very long time. Tradeoffs for performance are pretty small if even measurable. Bob . . . ________________________________________________________________________________
Date: Feb 23, 2010
From: Ken <klehman(at)albedo.net>
Subject: Re: Failure Modes with Z14
Yes I was thinking that a small Bosch "40" amp relay and fuse would be quite adequate for turning my main bus into an E bus since my main bus loads are under 20 amps. Halogen landing lights and nav lights are the only things on it that draw significant power. With my key starter switch, it is not possible to crank the engine unless the main bus contactor is closed. Similar to a car, first key position closes the main bus contactor and then the spring loaded position cranks the engine. It has worked well for me. Alternatively, with a 20 amp or larger second alternator, most folks could eliminate the crossfeed contactor and then dual main bus contactors would in fact be the crossfeed. Ken Robert L. Nuckolls, III wrote: > > > At 09:38 AM 2/22/2010, you wrote: >> >> Jeff >> >> The 2 little Dekka 8 AH batteries on my Z-14 system are indeed >> equivalent to one 16AH battery except for being more expensive. They >> have large bolted lead terminals and one will start the subaru. Two >> are better when it is very cold. The batteries do what the >> manufacturer says. Small batteries with small terminals that are not >> designed to start engines will be a different story. > > Yes, the Dekka products are unique for their size. > >> My system does indeed allow charging both batteries with any single >> contactor failure. Not a big deal but a consideration with small >> batteries. Both alternators feed through their OV contactors to the >> respective battery. No second contactor between them and the batteries. > > Your words generate an interesting idea . . . > > Assume the builder chooses commercial off the shelf > IR alternators and a variant on Z-24 for control and > ov protection. In this instance, one COULD set the > altenrator b-lead contactor next to a battery contactor > and tie it's output directly to the battery. > > This configuration satisfies the legacy design goal > of minimizing hot fat-wires when all switches are > OFF. Now you can have your battery contactors feed > a single main bus. No e-bus is needed since you're > not likely to every need battery-only ops. Now you > have two, independently alternator-supported batteries. > Two battery busses to distribute loads for an electrically > dependent engine. A main bus that's not subject to > single-point-of-failure. Cool. > > I'll pray over this a bit. Perhaps a Figure Z-8 is > being conceived . . . > > Bob . . . > ________________________________________________________________________________
Date: Feb 23, 2010
From: Bill Mauledriver Watson <MauleDriver(at)nc.rr.com>
Subject: Re: Strobe power ground?
Robert L. Nuckolls, III wrote: > > > At 02:29 PM 2/22/2010, you wrote: >> >> >> I have no idea whether it is acceptable - but I have a #8 running >> from my batteries to the forest of tabs on the firewall with the >> thought that the tab is grounded to the airframe and directly. Feel >> good about it and think I discussed it with Bob here sometime ago. > > ???? Did I recommend this . . . or just offer that > it didn't hurt anything ??? > > Bob . . . > You definitely didn't recommend it and from what I can see didn't even offer a comment. My bad in suggesting you did. ________________________________________________________________________________
Date: Feb 23, 2010
Subject: Re: Loss of LR3C compared to switcher
From: rparigor(at)suffolk.lib.ny.us
Hi Bob Thx. for the reply. ">>Curiosity question, according to B+C a SD20S alternator turning when >>hot at 2500RPM it will produce 24 amps at 14V, how much approximate >>loss will there be using a LR3C regulator? How much approx. loss >>using a switcher? >> >>Same question for SD20S at 2000RPM, 15 amp output at 14V?" " "> No difference. The regulator's influence on max current > available is minimal. The alternators driven from a > vacuum pump pad are RPM limited. > " " I may not understand what you said, or I find what I think you said hard to believe. Are you saying that a LR3C creates no loss what so ever off the listed output of a SD20S on B+Cs spec sheet? Are you saying thata switcher is not more efficient than a linear regulator? I was hoping perhaps someone had actual measured losses. B+C never measured a switcher, but thinks perhaps LR3C will incur a 1.5 amp loss (the more amps, the more loss) not more than 2 amps in my scenario. Thx. Ron Parigoris ________________________________________________________________________________
Date: Feb 23, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Loss of LR3C compared to switcher
At 02:34 PM 2/23/2010, you wrote: >Hi Bob >Thx. for the reply. >">>Curiosity question, according to B+C a SD20S alternator turning when > >>hot at 2500RPM it will produce 24 amps at 14V, how much approximate > >>loss will there be using a LR3C regulator? How much approx. loss > >>using a switcher? > >> > >>Same question for SD20S at 2000RPM, 15 amp output at 14V?" > >" "> No difference. The regulator's influence on max current > > available is minimal. The alternators driven from a > > vacuum pump pad are RPM limited. > " " > >I may not understand what you said, or I find what I think you said >hard to believe. Are you saying that a LR3C creates no loss what so >ever off the listed output of a SD20S on B+Cs spec sheet? Are you >saying that a switcher is not more efficient than a linear >regulator? I was hoping perhaps someone had actual measured losses. >B+C never measured a switcher, but thinks perhaps LR3C will incur a >1.5 amp loss (the more amps, the more loss) not more than 2 amps in >my scenario. Not sure what you're calling "losses". The controlling device in a plain-vanilla duty-cycle controlled regulator does not get as hot as the linear device. However, just because a linear tosses off heat (maximum when the field voltage is 1/2 of bus voltage) doesn't mean that there's more energy available from the alternator. Minimum speed for regulation, minimum speed for full output and maximum output are measured under conditions that the regulator is turned on max-hard. In both styles this is 100% duty cycle output with the field voltage being only a tad below bus voltage. The drop in a max-on linear vs. a max-on switching regulators might be a bit different . . . but both are on the order of 1 volt. In a belt driven alternator running nearly 10,000 rpm, this is an insignificant drop that does not limit the alternator's ability to deliver max rated power. When you're RPM limited, then it MAY be that one regulator may produce a tad more output. You'd have to do a side-by-side bench test or have access to the alternator's transfer function curves for the RPM of interest. In any case, the differences are small and mostly academic . . . if ones successful termination of flight in the endurance mode hinges on the availability of just a tad more alternator output, the load analysis for that condition needs to be re-evaluated. Keep in mind too that field current supplied through the regulator comes from the bus and is probably on the order of 2.5 amps. This is PART of your running load. So energy available to run the elecro-whizzies is taxed by the value of field supply current. For internally regulated alternators, rated output is over and above field supply requirements. But for the SD-20 in an RPM limited mode, the field current comes off the top of what ever the total output of the alternator happens to be. A switching regulator of any style cannot improve upon that. Bob . . . ________________________________________________________________________________
Date: Feb 23, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Strobe power ground?
>> ???? Did I recommend this . . . or just offer that >> it didn't hurt anything ??? >You definitely didn't recommend it and from what I can >see didn't even offer a comment. My bad in suggesting you did. No problem. With as many conversations as I participate in on-list, off-list and with clients, it's difficult to recall sometimes just who said what to whom and why. That's the nice thing about archives. I've got every document I ever posted to the List on file. It's been handy on many occasions over the years. Bob . . . ________________________________________________________________________________
Date: Feb 23, 2010
From: Jeff Page <jpx(at)qenesis.com>
Subject: Re: Failure modes with Z14
Joe, I am quite comfortable with the situation that would occur if any of the individual parts of Z13/8 should fail. I don't expect a contactor failure is any more significant than other failures. What I like about Z13/8 is that there are alternate feed paths so that the alternator(s) can continue to keep the batteries charged, and power can be supplied to the endurance bus. I once drove a car all winter without a functioning alternator. It was mounted on the bottom of the engine and I didn't want to lie in the snow to fix it. I knew how many starts and how long I could drive with and without the headlights. I only got caught needing a boost once all winter ;-) So the only thing that I would like to do is ensure that an overvoltage condition cannot damage both ignitions. Perhaps two OV modules would do it, but I would feel more comfortable with an isolated system. Ken, > The 2 little Dekka 8 AH batteries on my Z-14 system are indeed > equivalent to one 16AH battery except for being more expensive. This is good to know. > My system does indeed allow charging both batteries with any > single contactor failure. How did you change the circuit to accomplish this ? > If it helps - yes I did spend some time testing the OV modules and yes > they perform exactly as advertised and the current version simply does > not trip unless there is a real OV event. Also useful to know. How did you test them ? I expect that applying 16V to the sense lead would result in the field breaker tripping. My concern would be duplicating the shorted regulator scenario, that is, applying 12V directly to the field terminal. This should result in the alternator producing possibly 80-120V ? Does the breaker trip in time to protect some cheap auto headlamps ? I don't think I want to do this test with my expensive ignitions. > Don't overlook ergonomics. Keep your system as operationally simple as > possible. Give some thought to what you actions you will take for > failures and locate controls to make those actions simple and > methodical. Ideally one procedure for all engine problems is ideal. This I have thought a lot about. In the end, I came up with a color coded system. If this LV light illuminates, flip the switches joined with the same color line. Easy to do in flight without a checklist (although I would use one anyway). No troubleshooting in flight. I would like opinions on the feasibility of modifying Z13/8 by isolating the aux alternator path with a cross feed relay that would be open in flight except after alternator failure. I would add a small battery to ensure the SD-8 produces power. Jeff Page Dream Aircraft Tundra #10 ________________________________________________________________________________
Date: Feb 23, 2010
From: ray <raymondj(at)frontiernet.net>
Subject: Re: Failure modes with Z14
Jeff, I would be interested in seeing your "Light/line" switch layout on your panel. Sounds like a good idea. Are there any pictures posted anywhere I can look at? Raymond Julian Kettle River, MN. Jeff Page wrote: > > Joe, > > I am quite comfortable with the situation that would occur if any of the > individual parts of Z13/8 should fail. I don't expect a contactor > failure is any more significant than other failures. What I like about > Z13/8 is that there are alternate feed paths so that the alternator(s) > can continue to keep the batteries charged, and power can be supplied to > the endurance bus. > > I once drove a car all winter without a functioning alternator. It was > mounted on the bottom of the engine and I didn't want to lie in the snow > to fix it. I knew how many starts and how long I could drive with and > without the headlights. I only got caught needing a boost once all > winter ;-) > > So the only thing that I would like to do is ensure that an overvoltage > condition cannot damage both ignitions. Perhaps two OV modules would do > it, but I would feel more comfortable with an isolated system. > > Ken, > >> The 2 little Dekka 8 AH batteries on my Z-14 system are indeed >> equivalent to one 16AH battery except for being more expensive. > > This is good to know. > >> My system does indeed allow charging both batteries with any >> single contactor failure. > > How did you change the circuit to accomplish this ? > >> If it helps - yes I did spend some time testing the OV modules and yes >> they perform exactly as advertised and the current version simply does >> not trip unless there is a real OV event. > > Also useful to know. How did you test them ? I expect that applying > 16V to the sense lead would result in the field breaker tripping. My > concern would be duplicating the shorted regulator scenario, that is, > applying 12V directly to the field terminal. This should result in the > alternator producing possibly 80-120V ? Does the breaker trip in time > to protect some cheap auto headlamps ? I don't think I want to do this > test with my expensive ignitions. > >> Don't overlook ergonomics. Keep your system as operationally simple as >> possible. Give some thought to what you actions you will take for >> failures and locate controls to make those actions simple and >> methodical. Ideally one procedure for all engine problems is ideal. > > This I have thought a lot about. In the end, I came up with a color > coded system. If this LV light illuminates, flip the switches joined > with the same color line. Easy to do in flight without a checklist > (although I would use one anyway). No troubleshooting in flight. > > I would like opinions on the feasibility of modifying Z13/8 by isolating > the aux alternator path with a cross feed relay that would be open in > flight except after alternator failure. I would add a small battery to > ensure the SD-8 produces power. > > Jeff Page > Dream Aircraft Tundra #10 > > > > > > > ________________________________________________________________________________
From: Richard Talbot <richard(at)talbots.net.au>
Date: Feb 24, 2010
Subject: Alt Cb Pops
G'day List, I have a problem that my Plane Power alternator has started poping the crowbar OV CB when I switch on the ignition. I have 90 hours so far without too many issues. I have checked wiring etc and run continuity checks. There is no resistance in the wiring runs. The current draw is 10A through the CB and it pops 3-5 seconds after switch on. Any ideas? I think the internals might have failed. Could there be a cheap fix? Thanks Richard ________________________________________________________________________________
Subject: Re: Failure modes with Z14
From: "user9253" <fran4sew(at)banyanol.com>
Date: Feb 24, 2010
Jeff, > Perhaps two OV modules would do it, but I would feel more comfortable with an isolated system. The advantage of building your own plane is that you can design it to meet your goals. > How did you test them? I expect that applying 16V to the sense lead would result in the field breaker tripping. My concern would be duplicating the shorted regulator scenario, that is, applying 12V directly to the field terminal. > Testing is accomplished by applying a high voltage directly to the OV module and not to the rest of the electrical system. Do this by disconnecting the wire to the OV module and inserting 2 D-Cells in series with the wire. The test can be conducted with the engine not running. See this circuit: http://tinyurl.com/ydpjzkl This document also describes testing the over voltage protection, but it does not test the circuit breaker: http://www.aeroelectric.com/DIY/DIY_Crowbar_OVP_F.pdf > I would add a small battery to ensure the SD-8 produces power. The SD-8 is a permanent magnet alternator. It does not require any battery power to excite the field windings because there are none. Bob N offers very good philosophy on the subject of backup systems: http://tinyurl.com/ybbdffj Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287974#287974 ________________________________________________________________________________
From: "Randy Pinkston" <pinkston(at)carolina.rr.com>
Subject: 3010042 fuel vmc transducer wtb
Date: Feb 24, 2010
Anyone have a vision micro fuel transducer # 3010042 for sale 704-694-5053 Randy Pinkston ________________________________________________________________________________
Date: Feb 24, 2010
From: Jeff Page <jpx(at)qenesis.com>
Subject: Re: Failure Modes with Z14
Ray, My circuit diagram and the switch panel layout are available here: http://www.qenesis.com/tundra/Electrical Jeff Page Dream Aircraft Tundra #10 Re: Failure Modes with Z14 > I would be interested in seeing your "Light/line" switch layout on your > panel. Sounds like a good idea. Are there any pictures posted anywhere > I can look at? > > Raymond Julian ________________________________________________________________________________
Date: Feb 24, 2010
From: Kenneth Johnson <kjohnsondds(at)yahoo.com>
Subject: Figure Z?
Hi Electrical Gurus,=0AI have been building a Zenith CH 801 for the past se veral years.- It has given me time to plan for engine placement and panel instruments.- Wiring the plane and panel has been a concern.- In placi ng questions on the internet regarding wiring, several people recommended t his site, along with purchasing the AeroElectric Connection.- After readi ng the AeroElectric Connection, I was looking for a schematic that would re flect the engine I am using.- I am using a Mazda rotary engine that has b een built by Dave Atkins.- It has a new Bosch AL394X alternator which ind icates it rectifies 100% and has its own voltage regulator.- The engine c omes with a Microtech LT-10 RX8 13B Sequential electronic engine management system.- =0A=0ABasically, this is an automotive engine.- It has one al ternator and no magnitos.- It has been build to produce about 180 hp.- What Z wiring diagram fits this engine?=0A=0AThe chapter on batteries sugge sts an Odyssey PC680 battery.- In doing research on this battery, it seem s to be indicated for a motorcycle engine.- Would it provide enough crank ing power?- Would the Odyssey PC925 battery be better?- Zenith recommen ds that the battery fit under the passenger seat.- Since the rotary engin e is lighter than the recommended Lycoming 360, the engine will probably be place more anterior from the firewall.- This will leave room to mound an Odyssey PC680 mounted to the firewall.- It weighs 15.4 pounds.--- ThePC 925 weighs 24 pounds and may be another story.=0A=0AIn reading, many times it suggested that grounding the engine should be done through the eng ine pan.- Is there a reason why the engine pan is used VS gounding direct ly to the engine block?=0A=0AThe Zenith 801 is a bush plane.- My goal in finishing the plane is to keep it as light as possible.- Over the last se veral months I have "listened" in on the discussion of fuses vs breakers an d whether a transponder is needed.- Basically, I believe what a person re ally needs is a list of parts needed to wire a panel and where they can be purchased.- There were good suggestions on fuse blocks and cup holders, b ut many things are missing.- I guess it first begins with which Z diagram I need to use and then, I can go from there.=0A=0AI have studied Spanish f or thirty years, and-can-do well.- However, if we had a discussion on auto parts in Spanish, I would be lost.- In reading your discussions on many issues, I feel like the kid who can tell you, "Where is the bathroom" in spanish, but is lost when asked to say more.- As a read more and more, I catch a little more.- However, there is a large void to fill.- =0A =0AThanks for your discussions=0A=0AKen Johnson=0A=0A=0A ________________________________________________________________________________
Date: Feb 24, 2010
From: ray <raymondj(at)frontiernet.net>
Subject: Re: Failure Modes with Z14
Jeff, Thanks for the link. Your layout looks like a good way to aid in decision making during high stress events. I will definitely include that feature in my panel planning. Raymond Julian Kettle River, MN. Jeff Page wrote: > > Ray, > > My circuit diagram and the switch panel layout are available here: > http://www.qenesis.com/tundra/Electrical > > Jeff Page > Dream Aircraft Tundra #10 > > Re: Failure Modes with Z14 > >> I would be interested in seeing your "Light/line" switch layout on your >> panel. Sounds like a good idea. Are there any pictures posted anywhere >> I can look at? >> >> Raymond Julian > > > > > > ________________________________________________________________________________
Subject: Re: Failure modes with Z14
From: "user9253" <fran4sew(at)banyanol.com>
Date: Feb 24, 2010
Jeff, I looked over your schematic at http://www.qenesis.com/tundra/Electrical/Tundra_Power_Wiring.pdf and it looks very good. It would be interesting to see the internal schematic for the low voltage module and the purpose of the wires connected to it from switches. I am not saying that anything is wrong, only that I do not know what is inside of that box and how it works. Good job. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=288019#288019 ________________________________________________________________________________
Subject: Figure Z?
Date: Feb 24, 2010
From: <longg(at)pjm.com>
Ken, This is quite an assortment of questions. It will be best to break them down. These are typical questions which can each be answered individually. Be sure to spend time to search the list archives for individual topics. Many of them answered before. On Batteries... I use the PC680 which is 17AH and has plenty of umph to kick over my 200 HP IO-375. It fits my design goals. As far as weight, about 15 pounds and yes it could go under your seat. As far as true capacity is concerned, you'll need to do a full analysis of your design goals and mission before buying. Remember, contactors live near batteries, batteries live where your design needs them. Front, back, wherever. In General any good recumbent gas battery www.bandc.biz will work well in the aircraft and can be installed in any position. Whoever wrote the book on grounding the airplanes electrical system via the engine oil pan is a complete Gomer. Hit him over the head. When's the last time you saw a battery ground go straight to the oil pan? The language may have intended another meaning. Bolt/Weld it to the block - that's it. Bob has several Z diagrams which lend themselves to auto or electrical dependent installation. Again, the diagrams are based on missions success and ultimately what you want or want to tolerate in your design. A bit of time and a good checkbook will fix most of the issues. Enjoy, Glenn -----Original Message----- From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Kenneth Johnson Sent: Wednesday, February 24, 2010 3:00 PM Subject: AeroElectric-List: Figure Z? Hi Electrical Gurus, I have been building a Zenith CH 801 for the past several years. It has given me time to plan for engine placement and panel instruments. Wiring the plane and panel has been a concern. In placing questions on the internet regarding wiring, several people recommended this site, along with purchasing the AeroElectric Connection. After reading the AeroElectric Connection, I was looking for a schematic that would reflect the engine I am using. I am using a Mazda rotary engine that has been built by Dave Atkins. It has a new Bosch AL394X alternator which indicates it rectifies 100% and has its own voltage regulator. The engine comes with a Microtech LT-10 RX8 13B Sequential electronic engine management system. Basically, this is an automotive engine. It has one alternator and no magnitos. It has been build to produce about 180 hp. What Z wiring diagram fits this engine? The chapter on batteries suggests an Odyssey PC680 battery. In doing research on this battery, it seems to be indicated for a motorcycle engine. Would it provide enough cranking power? Would the Odyssey PC925 battery be better? Zenith recommends that the battery fit under the passenger seat. Since the rotary engine is lighter than the recommended Lycoming 360, the engine will probably be place more anterior from the firewall. This will leave room to mound an Odyssey PC680 mounted to the firewall. It weighs 15.4 pounds. ThePC 925 weighs 24 pounds and may be another story. In reading, many times it suggested that grounding the engine should be done through the engine pan. Is there a reason why the engine pan is used VS gounding directly to the engine block? The Zenith 801 is a bush plane. My goal in finishing the plane is to keep it as light as possible. Over the last several months I have "listened" in on the discussion of fuses vs breakers and whether a transponder is needed. Basically, I believe what a person really needs is a list of parts needed to wire a panel and where they can be purchased. There were good suggestions on fuse blocks and cup holders, but many things are missing. I guess it first begins with which Z diagram I need to use and then, I can go from there. I have studied Spanish for thirty years, andcando well. However, if we had a discussion on auto parts in Spanish, I would be lost. In reading your discussions on many issues, I feel like the kid who can tell you, "Where is the bathroom" in spanish, but is lost when asked to say more. As a read more and more, I catch a little more. However, there is a large void to fill. Thanks for your discussions Ken Johnson ________________________________________________________________________________
Date: Feb 24, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: Alt Cb Pops
At 05:47 AM 2/24/2010, you wrote: > > >G'day List, > >I have a problem that my Plane Power alternator has started poping the >crowbar OV CB when I switch on the ignition. I have 90 hours so far >without too many issues. > >I have checked wiring etc and run continuity checks. There is no >resistance in the wiring runs. The current draw is 10A through the CB >and it pops 3-5 seconds after switch on. Hmmmm . . . I think the breaker is 5A. A 10A draw is indeed suspicious. The max draw on this wire is generally no more than 3 to 3.5 amps engine stopped and much less in flight. >Any ideas? I think the internals might have failed. Could there be a >cheap fix? Probably not. Shorted turns in the field winding are the most plausible hypothesis but I have a hard time figuring out how this might happen. You'll probably have to return it to PlanePower for diagnosis . . . but if you have MEASURED a 10A draw before the breaker pops, then it's a certainty that something is wrong inside the alternator. Bob . . . ________________________________________________________________________________
Date: Feb 24, 2010
Subject: Official color of levers
From: rparigor(at)suffolk.lib.ny.us
Is there an officiallisting ofcolor to be used on balls or knobs for control levers? I think Black for throttle, Blue for prop, Red for mixture. How about cowl flap, choke, wheel brake, glider airbrake and doors? If not official, what would standard practice for color be for cowl flap, choke, wheel brake, glider airbrake and door? I want to have my aluminum balls and knobs anozied and there are plenty of colors to choose from sooooo.... Thx. Ron Parigoris ________________________________________________________________________________
Date: Feb 24, 2010
Subject: Re: GPU for Piper
From: John McMahon <blackoaks(at)gmail.com>
Bob, Could you expand on the two philosophies or point me to a further discussion. I've been wrestling with both ways and each time I decide one way, I think about it some more and change my mind...again? Is either choice superior or is it six of one and half a dozen of the other? As usual, thanks for all the thought and knowledge you share with all of us. On Sun, Feb 14, 2010 at 7:03 AM, Robert L. Nuckolls, III < nuckolls.bob(at)aeroelectric.com> wrote: > nuckolls.bob(at)aeroelectric.com> > > > You also need to see how the ship's battery > is tied to the system when ground power is plugged > in. Some manufacturers tied their ground power > to the battery side of the battery contactor. > This allowed charging a battery externally without > having the whole airplane "hot". Others tied it > to the bus such that ground power could operated > the airplane with the ship's battery contactor > open. There are good reasons for either philosophy, > you need to know which one has been applied to > your airplane. > ________________________________________________________________________________
Date: Feb 24, 2010
From: "Brooks Wolfe" <slipstream(at)wavecable.com>
Subject: GNS430 Wire Book
I'm still trying to sort out my GNS430W's lack of comm. I had the unit bench tested here locally, and it works just fine at the avionics shop, s o the issue must be my wiring somewhere. The wire book for AGATE that I've downloaded shows the 430 being hooked up through the GMA340. All I want to use is a simple Sigtronics intercom; no audio panel. The Sigtronics does not have "audio low" or "mic low" inputs. I believe I read somewhere that these are to be grounded, so that's what I did, but I can't find that reference right now. The Garmin manual (4.7.2.3) states that they're balanced inputs, and that both must be connected. I'm a bit wary of experimenting willy-nilly with this radio, so I haven't gone and tried tying them together yet. Also, the AGATE wire book shows a "Comm Mic Return" pin 8 on P4002, to be joined with the Comm Audio Lo. The Garmin manual simply shows that as a reserved or unused pin. Brooks Wolfe ________________________________________________________________________________
From: "JOHN TIPTON" <jmtipton(at)btopenworld.com>
Subject: Re: Official color of levers
Date: Feb 25, 2010
Hi Guys And what colours (colors) are recommended for the various warning lights Regards John (England) ----- Original Message ----- From: rparigor(at)suffolk.lib.ny.us To: AeroelectricList Sent: Thursday, February 25, 2010 4:10 AM Subject: AeroElectric-List: Official color of levers Is there an official listing of color to be used on balls or knobs for control levers? I think Black for throttle, Blue for prop, Red for mixture. How about cowl flap, choke, wheel brake, glider airbrake and doors? If not official, what would standard practice for color be for cowl flap, choke, wheel brake, glider airbrake and door? I want to have my aluminum balls and knobs anozied and there are plenty of colors to choose from sooooo.... Thx. Ron Parigoris ________________________________________________________________________________
Subject: Re: Official color of levers
From: "mmayfield" <mmayfield(at)ozemail.com.au>
Date: Feb 25, 2010
I'm not aware of any mandatory standard colour code convention for cockpit controls. Take a browse through some cockpit photos and you will see. Some are decidedly uncolourful! There are however conventions which are generally adhered to when colour is used. They generally fall in an order of importance. Red is vital (examples may be fuel/oil shutoff valves, anything which will stop your engine running if it's not in the right spot, fire extinguisher handles). Yellow is important (examples may be canopy latches, park brake lever, something which could cause embarrassment or damage if it's not in the right spot). Anything else doesn't matter too much. As for lights - the design follows a pattern of urgency and the convention is widely adhered to in my experience: Red: You need to take positive action now (eg - fire detected, you've just stalled). Amber: You need to take action pretty soon (eg - low/overvoltage, door unlocked, something has low pressure when it shouldn't). Green/Blue/White: I'm telling you something you might like to know (eg - gear down). Even the modern EICAS/glass planes are designed like this with their messaging systems. Red is bad & you better do something pronto. Amber is important, but probably won't kill you just yet. White is just telling you something. Green is the gear down & locked. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=288109#288109 ________________________________________________________________________________
From: "glen matejcek" <aerobubba(at)earthlink.net>
Subject: RE: Official color of levers
Date: Feb 25, 2010
Subject: AeroElectric-List: Official color of levers HI Ron- In a glider, flaps are grey, speed / air / dive brakes are blue, and canopy release / jettison are red. Wheel brakes are typically either a metallic bicycle brake-type affair mounted just below the stick grip or are incorporated into the dive brake at the extreme end of the deploy travel. >Is there an officiallisting ofcolor to be used on balls or >knobs for control levers? >I think Black for throttle, Blue for prop, >Red for mixture. How about cowl flap, choke, wheel brake, glider airbrake >and doors? >If not official, what would standard practice for color be >for cowl flap, choke, wheel brake, glider airbrake and door? I want to >have my aluminum balls and knobs anozied and there are plenty of colors to >choose from sooooo.... >Thx. >Ron Parigoris glen matejcek aerobubba(at)earthlink.net ________________________________________________________________________________
Date: Feb 25, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: GPU for Piper
At 11:30 PM 2/24/2010, you wrote: >Bob, Could you expand on the two philosophies or point me to a >further discussion. I've been wrestling with both ways and each >time I decide one way, I think about it some more and change my >mind...again? Is either choice superior or is it six of one and >half a dozen of the other? If you hook ground power to the battery side of the GP_Contactor, you can charge the battery without powering up the aircraft. Further, you would not be able to hook ground power to the aircraft WITHOUT having the battery on line as well. This would be my preferred configuration. Production TC do it both ways but predominantly the OTHER way. I'm mystified as to the rationale for doing it the other way . . . somebody made that decision long before my time and isn't around to explain it any more. I'm unable to deduce any advantage that would give it precedence over the first way. I am presuming that they had a "good" reason but I don't know what it is. Bob . . . ________________________________________________________________________________
Date: Feb 25, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Re: GNS430 Wire Book
At 11:41 PM 2/24/2010, you wrote: >I'm still trying to sort out my GNS430W's lack of comm. I had the >unit bench tested here locally, and it works just fine at the >avionics shop, so the issue must be my wiring somewhere. The wire >book for AGATE that I've downloaded shows the 430 being hooked up >through the GMA340. All I want to use is a simple Sigtronics >intercom; no audio panel. > >The Sigtronics does not have "audio low" or "mic low" inputs. I >believe I read somewhere that these are to be grounded, so that's >what I did, but I can't find that reference right now. Yes . . . when those pins are not available as dedicated inputs, use signal or power grounds as close to the intercom's cable connector as practical . . . > The Garmin manual (4.7.2.3) states that they're balanced inputs, > and that both must be connected. I'm a bit wary of experimenting > willy-nilly with this radio, so I haven't gone and tried tying them > together yet. > >Also, the AGATE wire book shows a "Comm Mic Return" pin 8 on P4002, >to be joined with the Comm Audio Lo. The Garmin manual simply shows >that as a reserved or unused pin. Hmmmm . . . I did those drawings some years ago and a tech over in experimental flight installed the radio. A week later I noticed that the radio was in and working . . . but if he found any errors in my drawing he didn't mention them. So I'm assuming that the drawings are correct as depicted. Is it just an audio issue? Which way . . . can't talk or can't hear or both? Does the transmitter key when you press the mic button. Bob . . . ________________________________________________________________________________
From: "ROGER & JEAN CURTIS" <mrspudandcompany(at)verizon.net>
Subject: RE: Official color of levers
Date: Feb 25, 2010
HI Ron- In a glider, flaps are grey, speed / air / dive brakes are blue, and canopy release / jettison are red. Wheel brakes are typically either a metallic bicycle brake-type affair mounted just below the stick grip or are incorporated into the dive brake at the extreme end of the deploy travel. And again..... What color was the throttle ball?? ________________________________________________________________________________
Subject: Re: Figure Z?
From: "user9253" <fran4sew(at)banyanol.com>
Date: Feb 25, 2010
Ken, You could pick one of the Z-Drawings, add to it and modify for the rotary engine, then post your schematic for others to comment on. If you do not know which drawing to start with, try Z-11. I agree with Glenn that the ground wire should be attached to a solid part of the engine, not to sheet metal. The PC680 should be adequate and meets your goal of light weight. You could ask Dave Atkins opinion. Do you have any information on the wiring requirements for the alternator or ignition? What about a fuel pump? Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=288144#288144 ________________________________________________________________________________
Date: Feb 25, 2010
Subject: RE: Official color of levers
From: "Matt Prather" <mprather(at)spro.net>
Gliders don't have throttles.. All the airplanes I have flown with throttles have black marking on that control. So far it sounds like the conflicts would be with the canopy release and mixture both being red, and the air brakes and propeller both being blue. Regards, Matt- > > HI Ron- > > In a glider, flaps are grey, speed / air / dive brakes are blue, and > canopy > release / jettison are red. Wheel brakes are typically either a metallic > bicycle brake-type affair mounted just below the stick grip or are > incorporated into the dive brake at the extreme end of the deploy travel. > > > And again..... What color was the throttle ball?? > ________________________________________________________________________________
Date: Feb 25, 2010
Subject: RE: Official color of levers
From: rparigor(at)suffolk.lib.ny.us
Hi Roger "And again..... What color was the throttle ball??" To my understanding the throttle balls of the vast majority of gliders are connected to the pilot. Thus usually hidden out of sight and color depends on race ;-) Ron Parigoris ________________________________________________________________________________
Date: Feb 25, 2010
From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>
Subject: Clearing some away some fog and fuzzy logic . . .
I've been invited in a private discussion where a builder is wrestling with his panel fabricator. Seems his hired wire-slinger has been discovered some stuff fuses vs. breakers and breakers only for crow-bar protected alternators. For many of you, this is pretty old stuff but this is a large group. For folks who have not followed this discussion for the last 15 years or so, I'll offer the following. The AeroElectric-List graybeards can delete and move on . . . Q: The Aeroelectric is such a proponent of Autocar Fuses . . . Bob: The PRIMARY attraction for fuses is equivalent protection for MUCH less cost and conservation of panel space. Q(continued) . . . instead of breakers because if it trips he says you should not attempt to put it back on while in the air, hence fuses makes sense...but in his diagrams he still adds a 5 amp breaker to alternator field instead of fuses.? But would one reset this breaker 'in flight' after it trips, cause re-setting breakers in flight could cause more harm, maybe you can explain a bit more. A(reader): Engaging the field circuit while the alternator is spinning at rated speed (i.e. - in flight) is hard on the alternator and even harder on the regulator and (my opinion only) should not be done on a regular or casual basis. Bob: Absolutely not true. This myth has been bubbling in old mechanic's tales cauldron for decades and has NO foundation in physics. There IS a phenomenon exhibited by some alternator regulators where energizing the alternator at light load and hi rpm produces an voltage overshoot that may even trip WHAT EVER ov protection is in place. This is a design feature of regulator dynamics that can be disconcerting but in no way does it represent a hazard to the alternator, regulator or the rest of the system.


February 05, 2010 - February 25, 2010

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