Today's Message Index:
----------------------
1. 01:15 AM - Re: OVP etc - do we have a bottom line? (owner-aeroelectric-list-server@matronics.com)
2. 01:52 AM - Re: OVP etc - do we have a bottom line? (Gerry Holland)
3. 05:12 AM - Re: Re: Fresh approach (n801bh@netzero.com)
4. 05:45 AM - Re: Re: Fresh approach (Mickey Coggins)
5. 06:58 AM - Re: PMags and RPM (Robert L. Nuckolls, III)
6. 07:24 AM - Re: Re: Fresh approach (Robert L. Nuckolls, III)
7. 07:34 AM - Re: OVP etc - do we have a bottom line? (Vern W.)
8. 07:39 AM - Re: OVP etc - do we have a bottom line? (Robert L. Nuckolls, III)
9. 07:45 AM - Eric's Plans/ Failure Modes? (Troy Scott)
10. 07:46 AM - Re: Zeftronics transistor (Robert L. Nuckolls, III)
11. 07:48 AM - Re: Looking for a B&C oil pressure switch (Robert L. Nuckolls, III)
12. 07:50 AM - Re: OVP etc - Bottom Line - Seeds of Z-20 are planted! (Robert L. Nuckolls, III)
13. 07:52 AM - Re: FADEC Relay (Robert L. Nuckolls, III)
14. 07:56 AM - Re: RAC Trim noise (Robert L. Nuckolls, III)
15. 08:13 AM - ptt problem (Ron Raby)
16. 09:05 AM - Re: Fresh Approach (Speedy11@aol.com)
17. 09:05 AM - Re: RAC Trim noise (Gilles Thesee)
18. 09:26 AM - Re: Looking for a B&C oil pressure switch pinout... (Harley)
19. 09:27 AM - Dear Bob; (Eric Ruttan)
20. 09:46 AM - Re: Help! (Mike Larkin)
21. 09:52 AM - Re: ptt problem (Mike Larkin)
22. 10:02 AM - Re: Help! (Chris Horsten)
23. 10:26 AM - Re: ptt problem (Ron Raby)
24. 11:08 AM - Re: Dear Bob; (Jerry Grimmonpre)
25. 11:21 AM - Day/Night mode for Digitrak or Pictorial Pilot (Dan Checkoway)
26. 11:57 AM - Re: Day/Night mode for Digitrak or Pictorial (David E. Nelson)
27. 12:26 PM - Re: Re: Fresh approach (Paul Messinger)
28. 02:01 PM - Re: OVP etc - do we have a bottom line? (Paul Messinger)
29. 02:01 PM - Well Bob you win (Paul Messinger)
30. 02:29 PM - Re: RAC Trim noise (Eric M. Jones)
31. 03:16 PM - Re: Re: RAC Trim noise (Gilles Thesee)
32. 03:35 PM - Re: OVP, grounds, resistive loads (Carlos Trigo)
33. 04:43 PM - Re: OVP etc - do we have a bottom line? (Robert L. Nuckolls, III)
34. 04:47 PM - Re: Dear Bob; (N1deltawhiskey@aol.com)
35. 04:52 PM - Re: Cessna A-510 ignition switch (Dj Merrill)
36. 05:14 PM - Re: Well Bob you win (Chuck Jensen)
37. 05:42 PM - Re: Cessna A-510 ignition switch (Wayne Sweet)
38. 05:42 PM - Re: Well Bob you win (Matt Prather)
39. 06:08 PM - Re: Dear Bob; (Jerry Grimmonpre)
40. 06:20 PM - P-Mag Excess Amps response (Joe & Jan Connell)
41. 06:21 PM - Re: Cessna A-510 ignition switch (Dj Merrill)
42. 06:48 PM - Re: Well Bob you win (n801bh@netzero.com)
43. 07:09 PM - Re: Zeftronics transistor (Brian Kraut)
44. 09:30 PM - Re: Looking for a B&C oil pressure switch pinout... (Werner Schneider)
Message 1
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| Subject: | OVP etc - do we have a bottom line? |
--> AeroElectric-List message posted by:
Paul, please,
You are addressing a bunch of builders who are not as electrically and
electronically savvy as yourself. I cannot welcome your sweeping
generalizations.
Engineering has trained me to the fact that all design decisions are
compromises. KISS is a question of perspective. Look at the modern automatic
car - seen from the driver's point of view, you can hardly make it simpler -
it is KISS to the nth degree, but look at the complexity behind the
dashboard... Operating a Lycoming is certainly lots more complex than
operating a car but that is because the stuff behind the airplane's
dashboard is a lot simpler than a car's. Remember the old cars way back in
the 10's and 20's, very simple electrical systems, with manual advance,
priming... but what a chore to start them, to run them and to avoid damaging
them.
This being said, I'll say that Bob Knuckolls has done a tremendous amount of
work which has profited thousands of builders. I very much respect him and
shall listen to what he has to say. He has established a very high degree of
credibility. The last thing we want is to discourage him. I've seen good
people leave lists because things got a little out of hand.
Please remember that most of us are trying our best to make intelligent,
knowledgeable choices on subjects we are far from mastering and we need
people such as Bob, and you, to remain on the list and to respond
knowledgeably.
As for your past posts, I have found them mostly positive. If you could
possibly keep them that way I'd say great and thank you.
Michele Delsol
RV8 - Fuselage - France
> -----Original Message-----
> From: owner-aeroelectric-list-server@matronics.com [mailto:owner-
> aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls,
> III
> Sent: Monday, April 04, 2005 8:27 AM
> To: aeroelectric-list@matronics.com
> Subject: Re: AeroElectric-List: OVP etc - do we have a bottom line?
>
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
> <b.nuckolls@cox.net>
>
> At 09:49 AM 4/3/2005 -0700, you wrote:
>
> >--> AeroElectric-List message posted by: "Paul Messinger"
> <paulm@olypen.com>
> >
> >I am sorry that the exchanges are so long and confusing (I am getting
> >confused myself).
> >
> >Much of the debate is regarding worst case design and the design approach
> of
> >the OVP that can false trigger.
> >
> >Then there is the current and the related CB ratings.
> >
> >Also there is the potential of alternator damage in the case of a false
> >trip.
> >
> >Lets go back and see where we are right now.
> >
> >The CB max no damage current rating is a personal concern to some and not
> a
> >big deal IF you have a real event as the alternator has failed. replacing
> >the CB may or may not be needed. A purest will replace it most will
> simply
> >press on by resetting. My objection is it does overstress the CB and a
> good
> >design of OVP would limit the current so there would be no question.
> >
> >The high current of hundreds of amps is a concern in some cases. It
> depends
> >on if you have steel tubes in the cockpit (many of us do) and even if not
> >the modern avionics sometimes include sensitive magnetometers that can be
> >overloaded with hi currents nearby (near by can be more than 12" and
> still
> >be too close. Finally if your engine depends on the 12 V bus to be above
> >some voltage to run there is a potential case when the OVP module trips.
> >this depends on the specific electronics. I have a documented case of
> >certificated aircraft having major compass errors accumulating over time
> >with currents around 50 amps max passing 18" away from the compass so it
> can
> >be a concern (The mandatory service bulletin to correct this problem
> will
> >be soon posted here for all to see).
> >
> >If you have a RV with Van's alternator add the recommended Transorbs and
> >consider using Erics OVP approach. If you have the Aeroelectric OVP any
> >false trip is unlikely to be a problem to the alternator with the added
> >Transorbs.
> >
> >There is little probability of problems with the B & C conversion using
> the
> >LR-3 regulator but adding "B" 'lead transorbs are recommended by both
> Eric
> >and myself on all alternators.
> >
> >If you have a Glastar or other aircraft with a steel tube inner or outer
> >cabin structure I would NOT use Bob's OVP module simply due to the poor
> >effects of HI currents in the cabin. IE careful wiring and transient
> >currents in the 50 amp or above might be hazardous to your flight
> >instruments and as a minimum a compass accuracy check on an annual basis
> is
> >recommended.
> >
> >In conclusion;
> >
> >There is simply no one size fits all that is safe to use. Most of the
> >builders are safe with the externally regulated LR-3 setup. some will be
> >unsafe with the use of Bob's OVP module and many are in the middle.
> >
> >However remember any who want to use the emergency mode of "No battery"
> need
> >to know that both the LR-3 and the OVP module have a 100% chance of
> tripping
> >the alternator off line with no battery and the often suggested addition
> of
> >a 25,000 mfd capacitor to "stabilize the alternator regulator is by test
> not
> >going to prevent false triggering of these devices from such simple
> things
> >as turning off landing lights or strobes or recognition lights if the
> >alternator is lightly loaded.
> >
> >No battery operation is my opinion a very important emergency mode of
> >operation.
> >
> >Here is what Bob has recently stated on this subject "but the question of
> >no-battery operation has never been addressed nor recommended in any of
> my
> >writings"
> >
> >I agree that none of his suggested schematic designs allow this mode
> simply
> >because they all include a LR-3 or OVP module that triggers with a load
> sump
> >(that Bob requires the battery to clamp). No battery, no clamp, first
> event
> >and alternator trips off line and no electrical power.
> >
> >But this is a different discussion.
> >
> >Sorry but as there is no one solution proposed todate we have no simple
> >reply.
> >
> >Paul
> >
> >
> >----- Original Message -----
> >From: "Vincent Welch" <welchvincent@hotmail.com>
> >To: <aeroelectric-list@matronics.com>
> >Subject: RE: AeroElectric-List: OVP etc - do we have a bottom line?
> >
> >
> > > --> AeroElectric-List message posted by: "Vincent Welch"
> > > <welchvincent@hotmail.com>
> > >
> > > A M E N ! ! !
> > >
> > >
> > >>From: Richard Riley <Richard@RILEY.NET>
> > >>Reply-To: aeroelectric-list@matronics.com
> > >>To: aeroelectric-list@matronics.com
> > >>Subject: AeroElectric-List: OVP etc - do we have a bottom line?
> > >>Date: Fri, 01 Apr 2005 07:47:28 -0800
> > >>
> > >>--> AeroElectric-List message posted by: Richard Riley
> <Richard@Riley.net>
> > >>
> > >>I've now spent much of the night trying to read and understand all the
> > >>objections to and defences of the crowbar OVP system.
> > >>
> > >>I still have no idea who's right. I just have a migraine.
> > >>
> > >>If I'm willing to spend enough money, can I build a system that
> satisfies
> > >>all the critics? For example, many of the crowbar posts involve
> > >>internally
> > >>regulated alternators. If I'm using a B&C 60 amp alternator, an LR3,
> and
> > >>SD8 and 2 batteries, am I still in danger of frying $50k worth of
> avionics
> > >>because I blinked wrong?
> > >>
> > >>Please understand, I am willing to spend whatever it takes to make
> this
> > >>problem (if it is a problem) go away. I don't want the "best"
> solution, I
> > >>want all the solutions that are worthwhile and applicable. I'm not
> going
> > >>to worry about an extra $100 for a transorb, I want belt and
> suspenders
> > >>and
> > >>nail gun and epoxy. Is that possible? Or are the approaches being
> > >>described mutually incompatible?
> > >>
> > >>
> > >
> > >
> > >
> >
> >
> >--
> >No virus found in this incoming message.
> >
> >
> >-- incoming mail is certified Virus Free.
>
>
> Bob . . .
>
>
> --------------------------------------------------------
> < Throughout history, poverty is the normal condition >
> < of man. Advances which permit this norm to be >
> < exceeded -- here and there, now and then -- are the >
> < work of an extremely small minority, frequently >
> < despised, often condemned, and almost always opposed >
> < by all right-thinking people. Whenever this tiny >
> < minority is kept from creating, or (as sometimes >
> < happens) is driven out of a society, the people >
> < then slip back into abject poverty. >
> < >
> < This is known as "bad luck". >
> < -Lazarus Long- >
> <------------------------------------------------------>
> http://www.aeroelectric.com
>
>
>
>
>
Message 2
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| Subject: | Re: OVP etc - do we have a bottom line? |
--> AeroElectric-List message posted by: Gerry Holland <gnholland@onetel.com>
Bonjour Michele
Bravo! at your entente cordiale! regarding OVP.
It came just in time as the subject had lost it's interest and caused me
enough aggravation to consider to unsubscribe, something I was not keen to
do.
The OBAM community can make choices for reliability and safety and many wise
words are said here in that vein. Recent technical discussions are aimed
down at a technical level that only leads to confusion and some self doubt
on earlier decisions.
For myself. I want a clear indication of a problem and then apply that to a
set of rehearsed actions to ensure that problem does not escalate to a fatal
conclusion. Many of the suggestions made help in that endeavour,
unfortunately they also contradict based on the fervour of each opinion
stated.
Come on Gentlemen! A short list of what criteria are essential to be met and
why, based on experience and proven reliability.
Salutations Cordiale Michele
Gerry
Europa 384 G-FIZY
Trigear with Rotax 912 and Arplast CS Prop.
Dynon EFIS, KMD 150, Icom A-200 and SL70 Transponder.
PSS AoA Fitted.
http://www.g-fizy.com
Mobile: +44 7808 402404
WebFax: +44 870 7059985
gnholland@onetel.com
Message 3
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| Subject: | Re: Fresh approach |
--> AeroElectric-List message posted by: "n801bh@netzero.com" <n801bh@netzero.com>
> best,
> .pdf's are most acceptable but I'll work with crayon on toilet paper
> if necessary. If you're offering the next greatest thing, let's get
> it out there for folks to exploit. I've hidden nothing, you've
> revealed nothing.
>
> Bob . . .
>
> "VERY WELL PUT" Bob. I have endured the same reception from
people in several internet chat rooms on my auto engine conversion. Virtually
all claims my powerplant wouldn't work came from arm chair engineers and nay
sayers who couldn't take apart a ball point pen. I have been in the racing,
fabricating and designing business longer then I care to admit. This is my first
homebuilt, and I try to think EVERYTHING through. So far it flies great, runs
real smooth, is getting better the expected fuel burn and most of all, it is not
following the "certified" designs of 60 year old technology.
> Of course anyone putting several times the HP in an airframe has to pushing
the envelope for sure, I knew it going in, planned for as many outcomes as
possible and used the best parts available.
>
> I admit the other guy has made some well versed statements and sounds up
to speed on the topic but like anything else ," the proof is in the
pudding". I speak for myself and probably a lot of other OBAM out there.
Bob has been there for us using common sense to help us wire our toys and I for
one certainly appreaciate it. Chin up Bob.
>
>
> Ben Haas
> N801BH
> www.haaspowerair.com
>
Ben Haas
N801BH
www.haaspowerair.com
Message 4
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| Subject: | Re: Fresh approach |
--> AeroElectric-List message posted by: Mickey Coggins <mick-matronics@rv8.ch>
> ... I have endured the same reception from
> people in several internet chat rooms on my auto engine conversion. Virtually
> all claims my powerplant wouldn't work came from arm chair engineers and nay
> sayers who couldn't take apart a ball point pen.
Ben,
As I learned in my high school chemistry class, "the universe is
entropy". It's much easier to tear things down than to
build them up.
Your engine package looks very slick. I love the photo on your
site where it looks like the VP is trying to get you trade aircraft.
BTW, do you have your wiring schematic somewhere up where I
can check it out? I assume your engine is electrically dependent,
like mine. I'm always interested in looking at how others have
done it.
Thanks,
Mickey
--
Mickey Coggins
http://www.rv8.ch/
#82007 Wiring
Message 5
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| Subject: | Re: PMags and RPM |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 06:37 AM 4/2/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: "Kelly Patterson" <kbob@cox.net>
>
>I'm a happy owner of an Emag and have spoken to the owners at length about
>the E & P models. So I'll quote what I know from memory, which we know can
>be flaky at times :)
>
>They have a big following in the plastic plane arena, and are gathering
>interest with the RV community. They did not indicate they monitor any
>'lists', they are simply working hard to start a new business and answer
>questions.
>
> From what I understand about the PMag.which I don't own, but may someday.
>The generator puts out 12-14V at approx. 1500 RPM, and drops voltage output
>as the RPM drops. The PMag & Emag will still make spark at some ridiculous
>low number like 5 V. So by generating 5+ V at 800 RPM it is self
>sustaining.
This feature in the E-mag's low voltage operation also says that
it's not subject to wandering off into the weeds during a starter-inrush
brownout . . . a battery powered ignition system truly designed to live
in the current world of aircraft DC power systems.
> The deal is - it has no excess voltage that can charge a
>battery below 1500 RPM, but it can help in a failed alternator situation
>above that RPM. Of course the output would be a very low amperage, and I
>wouldn't count on continued flight after an alternator failure.
An you wouldn't want it to. Having a DEDICATED low energy power source
to support a low energy but very important operating requirement is
good design. Further, given that the energy requirements for the e-mag
are so low, it represents a lower energy budget for calculating battery-
only operations. Adding the "p-" only shifts alternator out ignition loads
from battery to internal power source . . . and in my mind that's a good
thing.
>That is the gist of it - no hard numbers - do some research on the website -
>your mileage will vary - and I love this list and it's wealth of
>information!
>
>Kelly Patterson
>RV-6A finishing & wiring
>PHX, AZ
>
>
>I think this sounds like a good question to ask the people that make the
>PMags. Does someone that plays a principle role in the company monitor
>the list?
I don't think so. I've spoken with them and had e-mails from them
directly but my sense is that they do not participate on the
AeroElectric-List.
They might be on others.
I'm planning a trip down to visit them this spring sometime.
> > In case of the unlikely scenario that the electrical system should die
> > and the RPM should fall below PMag's self sustaining level, would wind
> > milling by diving bring the engine RPM up sufficiently, thereby
> > restoring engine power?
> >
> > A similar scenario would occur as one is on short final with engine at
> > 800 RPM. If the electrical system is down, are we in a situation
> > whereby the PMag could stop generating its own electricity, thereby
> > committing the flight to a definitive landing no matter what, i.e. no
> > go around possibility?
If you had a dark panel and knew that the p-mag needed minimal
engine speed to continue to function, why would you ALLOW rpm
to drop below some minimum value until your comfortable arrival
was assured?
Bob . . .
Message 6
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| Subject: | Re: Fresh approach |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 12:09 PM 4/4/2005 +0000, you wrote:
>--> AeroElectric-List message posted by: "n801bh@netzero.com"
><n801bh@netzero.com>
>
>
> > best,
> > .pdf's are most acceptable but I'll work with crayon on toilet paper
> > if necessary. If you're offering the next greatest thing, let's get
> > it out there for folks to exploit. I've hidden nothing, you've
> > revealed nothing.
> >
> > Bob . . .
> >
> > "VERY WELL PUT" Bob. I have endured the same reception from
>people in several internet chat rooms on my auto engine conversion. Virtually
>all claims my powerplant wouldn't work came from arm chair engineers and nay
>sayers who couldn't take apart a ball point pen. I have been in the racing,
>fabricating and designing business longer then I care to admit. This is my
>first
>homebuilt, and I try to think EVERYTHING through.
And you've probably discovered, it's very USEFUL to have conversations
with others who understand the role of good critical design review . .
. they
are invaluable resources for thinking EVERYTHING trough. It's a win-win
. . .
either good ideas are deduced as sound and bad ideas are prevented from
going into production.
> So far it flies great, runs
>real smooth, is getting better the expected fuel burn and most of all, it
>is not
>following the "certified" designs of 60 year old technology.
> > Of course anyone putting several times the HP in an airframe has to
> pushing
>the envelope for sure, I knew it going in, planned for as many outcomes as
>possible and used the best parts available.
> >
> > I admit the other guy has made some well versed statements and sounds up
>to speed on the topic but like anything else ," the proof is in the
>pudding". I speak for myself and probably a lot of other OBAM out there.
>Bob has been there for us using common sense to help us wire our toys and
>I for
>one certainly appreaciate it. Chin up Bob.
Thank you. This isn't a battle to be won or lost. It's an arena of ideas
wherein every idea should be evaluated for suitability to task. The hard
part is defining "task" and "suitability" in real numbers and failure
mode effects analysis and then fitting that to the marketplace.
Eric's description of what he would do "if it were my airplane" has offered
the greatest insight yet. Single bus, manual battery switch, alternator as
reliable as prop bolts, but add Transorbs no so much for real OV
protection as
for load-dump protection when a battery that is NOT as reliable as prop
bolts
opens up.
My philosophy for design assumes that any part of the airplane can fail and
to offer architectures that mitigate various levels of failures to be
tolerated depending on how the airplane is equipped and used.
The "new age" system still needs a second battery of some kind to support
products not designed to live in the "old age" aircraft systems that wander
of into the weeds during starter inrush brownout intervals. The "new
age" system would still need battery bus(ses) to support system-cold ops
of things like dome lights and, of course, those items not designed to live
in the "old age" system.
So the full-up, "new age" system is still a three bus system (figure z-11
with a second battery, no e-bus, manual battery switches, no alternator
control switch, no OV protection, and transorbs for mitigating the
inevitable load dump transients from an alternator running sans battery.
One would also want to have a definitive part numbers and manufacturers
who offers the alternator as reliable as prop bolts and it wouldn't
hurt to offer part numbers and manufacturers of batteries that are
also blessed with superior reliability. I chose to offer architectures
wherein I don't care what alternator (or battery) is used. The "new age"
system
should be very specific as to components suited to the task. I would also
be interested in the battery servicing philosophy . . . can we run this
battery 'til it dosen't crank the engine any more? We can run airborne
without it comfortably . . . it seems that one goal of the "new age" system
is to wring every last watt-second of functionality out of the battery.
Or, should we still do attentive preventative maintenance on the battery
so as to support alternator-out operations . . . oops, no that guy is
as reliable as prop bolts so we can run the battery dry.
For the first time, I think I'm getting a picture of what's being proposed.
How about it Eric and Paul, am I close? Please correct any misconceptions.
As soon as the architecture and recommended operating philosophies are
defined, ONLY THEN do we know enough about it to ask/answer the definitive
questions for an FMEA and the sifting of simple-ideas.
Bob . . .
Message 7
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| Subject: | Re: OVP etc - do we have a bottom line? |
--> AeroElectric-List message posted by: "Vern W." <vernw@ev1.net>
> Come on Gentlemen! A short list of what criteria are essential to be met
and
> why, based on experience and proven reliability.
>
> Salutations Cordiale Michele
The difficulty I'm having with the current OVP debate is that, besides
being above my head, these solutions are being presented as one-fits-all
arrangements (Crowbar good/bad, Transorb good/bad... whatever). I
understand the "meat" (schematics) of the electronics going on, but I don't
understand the philosophy with regard to negative effects downstream of an
OVP initiation and where I might better use one type of OVP over the other.
I make this comment thinking that I'm not alone among the non-pros who are
lurking here in the AE list hoping to find some help.
There are reasons why different people choose different "basic" systems
to go with our specific applications, and I'm having trouble trying to fit
in parts of this discussion with what I am specifically trying to do.
For example, and specifically in my case, I like the basic design
philosophy of Bob's Z-13, but I'm uncomfortable with what I see as a weak
link being what happens if a battery terminal breaks, i.e., both alternators
become just dead weight. At the same time, I don't feel the need or expense
of going with a full "split" dual alt/dual batt system like the Z-14.
So what I'd like to do is to stay with the Z-13 system and "simply" add
an additional 4.5amp battery somewhere in the system that will serve as both
a backup power source for JUST the electronic ignition (as recommended by
Lightspeed), AND as an exciter for either of the alternators. I want the
4.5amp battery to be able to be charged by either alternator, but to only
supply power to the ignition unless intentionally switched into the Aux.
buss. A system like that, and with bullet-proof OVP (whether Crowbar or
Transorb), will allow me to happily fly over mountains and large bodies of
water.
I'm just not up to speed on where this OVP debate fits in with what I am
wanting to do.
Vern
----- Original Message -----
From: "Gerry Holland" <gnholland@onetel.com>
Subject: Re: AeroElectric-List: OVP etc - do we have a bottom line?
> --> AeroElectric-List message posted by: Gerry Holland
<gnholland@onetel.com>
>
> Bonjour Michele
>
> Bravo! at your entente cordiale! regarding OVP.
>
> It came just in time as the subject had lost it's interest and caused me
> enough aggravation to consider to unsubscribe, something I was not keen to
> do.
>
> The OBAM community can make choices for reliability and safety and many
wise
> words are said here in that vein. Recent technical discussions are aimed
> down at a technical level that only leads to confusion and some self doubt
> on earlier decisions.
>
> For myself. I want a clear indication of a problem and then apply that to
a
> set of rehearsed actions to ensure that problem does not escalate to a
fatal
> conclusion. Many of the suggestions made help in that endeavour,
> unfortunately they also contradict based on the fervour of each opinion
> stated.
>
> Come on Gentlemen! A short list of what criteria are essential to be met
and
> why, based on experience and proven reliability.
>
> Salutations Cordiale Michele
>
> Gerry
>
> Europa 384 G-FIZY
> Trigear with Rotax 912 and Arplast CS Prop.
> Dynon EFIS, KMD 150, Icom A-200 and SL70 Transponder.
> PSS AoA Fitted.
>
> http://www.g-fizy.com
> Mobile: +44 7808 402404
> WebFax: +44 870 7059985
> gnholland@onetel.com
>
>
Message 8
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| Subject: | Re: OVP etc - do we have a bottom line? |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 08:32 PM 4/3/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: "B. Wright" <r.wmitty@gmail.com>
>
>Gentlemen:
>
>I seem to be getting copies of material that you may not want public?
>I am not part of your group or organisation and really don't need to
>know about your unsolved stress points. I have been receiving several
>of these emails this evening?
Don't know who wouldn't want it public. I have nothing
to hide and don't believe I've done anything I should
be ashamed of.
What we're discussing is a alternative architecture and
fabricating philosophy for an aircraft electrical system
design. It may have a great deal of merit but we won't
know until all is laid out on the table for everyone to
ponder and formulate questions that are part of any
good critical design review.
If you detect some stress in my words, be advised that it's
only frustration and not anger. But I am to the point where
I'll have to insist on forthright and open participation of
the other participants for me to continue. At the moment
I don't see ideas and understanding moving forward and I
do have other things to do if this train doesn't get moving.
I'm comfortable with either outcome.
Bob . . .
Message 9
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| Subject: | Eric's Plans/ Failure Modes? |
--> AeroElectric-List message posted by: "Troy Scott" <tscott1217@bellsouth.net>
Eric,
Would you please discuss possible failure modes with your plan for your
GlaStar?
Please include the maintenance required after each failure, and how you
would go about performing said maintenance (how invasive is it?, etc..)
Regards,
Troy
ERIC WROTE:
My opinion only---and I have a lot of them. I am building a Glastar and as
of this date, here's what I believe is going into it----
1) I would buy a new or expertly rebuilt internally regulated Nippondenso
55A (or so).
2) I would use a fusible link as the B+ lead from the alternator and hang
off it 6 X 5kW 18V unidirectional Transorbs (and one or two bi-directionals
around, too). It would be fine and perhaps preferable to distribute these
Transorbs, the reason being that a lightning strike might well do less
damage is the transorbs are generally sprinkled instead of grouped.
3) Battery disconnect contactor would be eliminated but if the FAA wants it
then I would design this as a pull-to-disconnect mechanical switch at the
battery terminals (from car racing products). Use only in a real crash
emergency and maybe a half-way-decent anti-theft device.
All the details of busses and batteries need to be worked out. But this is a
core part. No crowbar, no OVP, no alternator contactor, no battery
contactor, no external regulator, no field breaker, no load dump concerns,
maximum reliability, minimum cost and weight.
Regards,
Eric M. Jones
www.PerihelionDesign.com
Message 10
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| Subject: | Re: Zeftronics transistor |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 07:05 PM 4/3/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: "Brian Kraut"
><brian.kraut@engalt.com>
>
>I have a Zeftronics R15100 voltage regulator that is blown because the
>previous owner of the plane used a shielded wire on the alternator without
>the shield insulated and it shorted to the field stud on the alternator.
Yup . . . field shorts will take down many regulator designs . . . A
B&C LR-3 uses the crowbar system to shut down the supply and protect the
regulator in case of a field short.
>The TO-220 output transistor is toasted and I can't read the complete part
>number on it. It is a TIP1 something. If I had to take a wild ass guess I
>would say a TIP120 is the most likely candidate, but I want to be sure.
>Does anyone know for sure or know where I can get a schematic?
You might call Zeftronics and ask . . . as for Femmi (assming
he's still there). He might just tell you the part number.
It's a plain vanilla transistor. Get someting good for 5A or more,
80v or more. Try a PNP and operate if from a variable power supply
on the bench using a 10 ohm resistor for a "field" load. 99% sure
this will fix it. I've not seen a practical approach to using an
NPN transistor in that slot on a regulator.
Bob . . .
Message 11
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| Subject: | Re: Looking for a B&C oil pressure switch |
pinout...
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
pinout...
At 11:29 AM 4/3/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: "Marcos Della" <mdella@cstone.com>
>
>
>Ok, I got one of the three connector switches. Normally I've seen the
>connections
>Marked as C, NC, and NO. On this one they are marked P, S, and I... So.
>Which ones
>Are which? w/o pressure, P and S are shorted... But I don't know which
>one of them
>Is the "common" lead...
I used to sell that switch and thought I had the data on it but
can't put my hands on it. Call Tim at B&C.
Bob . . .
Message 12
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| Subject: | RE: OVP etc - Bottom Line - Seeds of Z-20 are planted! |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 11:01 AM 4/3/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
>
>Paul Messinger forced all this to condense and the more I look at it the
>more I like it.
>
>My opinion only---and I have a lot of them. I am building a Glastar and as
>of this date, here's what I believe is going into it----
>
>1) I would buy a new or expertly rebuilt internally regulated Nippondenso
>55A (or so).
>
>2) I would use a fusible link as the B+ lead from the alternator and hang
>off it 6 X 5kW 18V unidirectional Transorbs (and one or two bi-directionals
>around, too). It would be fine and perhaps preferable to distribute these
>Transorbs, the reason being that a lightning strike might well do less
>damage is the transorbs are generally sprinkled instead of grouped.
>
>3) Battery disconnect contactor would be eliminated but if the FAA wants it
>then I would design this as a pull-to-disconnect mechanical switch at the
>battery terminals (from car racing products). Use only in a real crash
>emergency and maybe a half-way-decent anti-theft device.
>
>All the details of busses and batteries need to be worked out. But this is a
>core part. No crowbar, no OVP, no alternator contactor, no battery
>contactor, no external regulator, no field breaker, no load dump concerns,
>maximum reliability, minimum cost and weight.
Thank you sir! Let me take these words and begin to craft Z-20. I'll
publish the drawing as soon as I can and you can start feeding me errata
and we can begin to discuss the companion notes that will help the
neophyte builder achieve the perceived performance levels.
Bob . . .
Message 13
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--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 11:18 PM 4/2/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: "Mark Taylor" <mtaylo17@msn.com>
>
>Listers,
>
>I have a relay with hooks on it as supplied with my FADEC Cabin harness kit.
>Pictures available at http://home.comcast.net/~mtaylo17/RV7/fadec.htm#Latest
>
>Does anybody know how I'm supposed to make a connection to this thing? Right
>now, I'm assuming I twist a loop in the wire, hook it on and solder it.
>
>Seems to go against convention of not soldering stuff if you can help it.
Yup, those are solder-hooks. Wrap the wire around it, solder it, cover with
heatshrink.
Bob . . .
Message 14
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| Subject: | Re: RAC Trim noise |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 10:51 PM 4/1/2005 +0200, you wrote:
>--> AeroElectric-List message posted by: Gilles Thesee
><Gilles.Thesee@ac-grenoble.fr>
>
>Hi all,
>
>I would appreciate your opinion about the following point :
>In our Rotax 914 powered MCR 4S, the only electrical noise audible is
>from the small RAC Trim in the right aileron, not far from the Bob
>Archer's VHF antenna in the wingtip. This is not a real nuisance, since
>the aileron trim is seldom used in flight.
>Nevertheless would a capacitor across the trim motor wires improve things ?
>
>Thanks for your advice,
>Regards,
Probably. Try 1000 pf ceramic capacitor across motor leads (white wires).
Bob . . .
Message 15
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--> AeroElectric-List message posted by: "Ron Raby" <ronr@advanceddesign.com>
To everyone:
I am having a problem with my push to talk on the pilot side. On the ground
and for a while during flight the push to talk works fine. It then stops
working. The copilot side works fine. The parts involved are the PS
engineering pma 7000, approach systems hub, approach system cables, Garmin
530 and an SL30.
I have rang out the cables directly up to the pma 7000. I cannot find a
problem. I have rang out the switch both when it is working and not and it
is ok. I have shut of the intercom during flight and it still does not work.
my gut feeling is something is not working in the pma 7000 when it gets
warm. Ideas would be appreciated.
Thanks
Ron Raby
Lancair ES
flying
----- Original Message -----
From: "Mickey Coggins" <mick-matronics@rv8.ch>
Subject: Re: AeroElectric-List: Re: Fresh approach
> --> AeroElectric-List message posted by: Mickey Coggins
> <mick-matronics@rv8.ch>
>
>> ... I have endured the same reception from
>> people in several internet chat rooms on my auto engine conversion.
>> Virtually
>> all claims my powerplant wouldn't work came from arm chair engineers and
>> nay
>> sayers who couldn't take apart a ball point pen.
>
> Ben,
>
> As I learned in my high school chemistry class, "the universe is
> entropy". It's much easier to tear things down than to
> build them up.
>
> Your engine package looks very slick. I love the photo on your
> site where it looks like the VP is trying to get you trade aircraft.
>
> BTW, do you have your wiring schematic somewhere up where I
> can check it out? I assume your engine is electrically dependent,
> like mine. I'm always interested in looking at how others have
> done it.
>
> Thanks,
> Mickey
>
> --
> Mickey Coggins
> http://www.rv8.ch/
> #82007 Wiring
>
>
>
Message 16
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| Subject: | Re: Fresh Approach |
--> AeroElectric-List message posted by: Speedy11@aol.com
In a message dated 4/4/2005 4:31:52 AM Eastern Standard Time,
aeroelectric-list-digest@matronics.com writes:
If you're offering the next greatest thing, let's get
it out there for folks to exploit. I've hidden nothing, you've
revealed nothing.
Well said!
Do not archive
Stan Sutterfield
www.rv-8a.net
Message 17
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| Subject: | Re: RAC Trim noise |
--> AeroElectric-List message posted by: Gilles Thesee <Gilles.Thesee@ac-grenoble.fr>
>>Nevertheless would a capacitor across the trim motor wires improve things ?
>>
>>Thanks for your advice,
>>Regards,
>>
>>
>
> Probably. Try 1000 pf ceramic capacitor across motor leads (white wires).
>
>
>
Bob,
Thanks a lot.
Regards,
Gilles Thesee
Grenoble, France
Message 18
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| Subject: | Re: Looking for a B&C oil pressure switch pinout... |
--> AeroElectric-List message posted by: Harley <harley@agelesswings.com>
>>they are marked P, S, and I...<<
Interesting...on the B&C website, the picture of that switch shows the
same terminology, but when clicking on the wiring diagram for it, it
shows, as you said, NC, NO and C!
If you do contact Tim, suggest that they change the wiring diagram!
Anyway, it sounds like you have a meter or a continuity device of some
kind to be able to determine that P and S are continuous with no
pressure, so one of them must be the common, and the other is the NC
terminal.
To determine which, I'd just put about 10 pounds of air pressure on it,
while having my meter leads connected to I and S, then again with I and
P...whichever one gives you continuity, is the common. And of course, I
is the NO lead.
Harley Dixon
Robert L. Nuckolls, III pinout... wrote:
>--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
pinout...
>
>At 11:29 AM 4/3/2005 -0700, you wrote:
>
>
>
>>--> AeroElectric-List message posted by: "Marcos Della" <mdella@cstone.com>
>>
>>
>>Ok, I got one of the three connector switches. Normally I've seen the
>>connections
>>Marked as C, NC, and NO. On this one they are marked P, S, and I... So.
>>Which ones
>>Are which? w/o pressure, P and S are shorted... But I don't know which
>>one of them
>>Is the "common" lead...
>>
>>
>
> I used to sell that switch and thought I had the data on it but
> can't put my hands on it. Call Tim at B&C.
>
> Bob . . .
>
>
>
>
Message 19
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--> AeroElectric-List message posted by: "Eric Ruttan" <ericruttan@chartermi.net>
Dear Mr. Nuckolls;
Last time I commented on this topic a very well known engineer ran away and
did not come back for months. I do not desire a repeat of that but I think
there are some problems that have not been addressed.
It is with deep personal respect for your thinking process and work ethic I
send these comments.
From: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
> .pdf's are most acceptable but I'll work with crayon on toilet paper
> if necessary. If you're offering the next greatest thing, let's get
> it out there for folks to exploit. I've hidden nothing, you've
> revealed nothing.
>
> Bob . . .
"I've hidden nothing, you've revealed nothing."
This is the single point I have perceived from the very beginning of this
discussion months ago. Claims are made. Ideas are shouted. But not a
single simple idea critique has been proposed. Not a single, real world,
valid critique, of any Z diagram has been made. Not single actually
verifiable experiment or test has been shown in support of this "critique".
In fact you have done experiments in response to these vague claims to
quantify an area of these vague claims as not valid.
Bob, at what point do you stop repeating yourself and realize your request
for clarification is not being addressed? At what point to you stop doing
work to disprove or quantify accusers unsupported and vague claims? When
should they be responsible for SUPPORTING data behind a critique, OR EVEN
CLEARLY ARTICULATING said critique?
> And you've probably discovered, it's very USEFUL to have conversations
> with others who understand the role of good critical design review . .
> . they
> are invaluable resources for thinking EVERYTHING trough. It's a
win-win
> . . .
> either good ideas are deduced as sound and bad ideas are prevented
from
> going into production.
I totally agree in the value of peer review. Bob, let me humbly suggest
this is not what is happening here. What I see is a vague and changing
critique of a well proven design. I see no clear articulation of simple
ideas or raw data to suggest we can even begin to determine what the
critique is. How can a discussion occur when peer reviewer will not clarify
to a "simple idea" the critique? I see you, Bob, having a discussion with
what you think they mean. I see you building an experiment showing an
entire area of these vague claims are not supported in your experiments.
The response to your experiment was to ask about parts, not get into the lab
and repeat it. Bob, what does that mean to you? It holds great meaning for
me.
> > Chin up Bob.
>
> Thank you. This isn't a battle to be won or lost. It's an arena of
ideas
> wherein every idea should be evaluated for suitability to task.
In your world it is an arena of ideas. But you are in the arena with
someone who wont share/talk about/quantify ideas. If that is true, and it
may not be, then I suggest you question your premise about where you are.
> The hard
> part is defining "task" and "suitability" in real numbers and failure
> mode effects analysis and then fitting that to the marketplace.
Bob, task is not hard. This "peer" discussion has refused to even addressed
task.
I cut your response to Eric's post. It also takes us down the same path.
Eric is a very bright guy. He knows that saying "I would do this" is
useless. It is the "because" that matters, which for some reason is missing
from his post.
Again I thank you for your time.
Eric
Message 20
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--> AeroElectric-List message posted by: "Mike Larkin" <mlas@cox.net>
I'm thinking ignition noise from a bad plug lead could be your problem.
Mike Larkin
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Chris
Horsten
Subject: RE: AeroElectric-List: Help!
--> AeroElectric-List message posted by: "Chris Horsten"
<airplanes@sympatico.ca>
Hi Matt,
Thanks for this hints
It's a Zenith CH-250. A further report from the ferry pilot reveals that
there is power. Radio is good during a message received, but reverts to
static once it ends. I will advise them re the TX as they probably don't
know that (I didn't). The aircraft was running perfect up until now. No
known issues. We did switch out the encoder about a week ago because the
last one seemed bad.
Re voltage being low I don't think this is the problem. Something is
generating some noise, because even the hand held is acting up and it is
operating on its own power. Engine is running fine and was started up at
least twice for a circuit after the problem surfaced. They are handing
off
to a mechanic this am I believe.
Other possible sources: Master relay? Noise filter (capacitor)? Voltage
regulator?
Chris
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
mprather
Subject: Re: AeroElectric-List: Help!
--> AeroElectric-List message posted by: mprather <mprather@spro.net>
Random questions and comments:
If it were the brushes, I would guess that there would be some warning
symptoms. I have had alternator brushes go bad before, and normally,
the
alternator light starts to flash occasionally, or just at start up.
Finally it gets bad enough that the battery is not getting charged, and
then
is dead.
Is this airplane new, or new to your friend? I am wondering about pre
existing, but undisclosed problems, like maybe the charging system never
actually worked, but the seller sent them on their way with a charged
battery. Now maybe it's low?
Does the engine crank okay with battery power?
Do the stranded folks have any diagnostic instrumentation at their
disposal?
It would be helpful if they either have a panel mounted volt/charging
meter,
or even better, if they have access to a multimeter. Check the battery
voltage with everything turned off, then again with the engine running.
My Narco transponder light stays on solid for the first few minutes of
operation (I assume during warmup). I wonder if they have left the txp
on
long enough to warm up.
I also wonder if bus voltage is so low that the com radio is having
problems
operating.
I am not a generator expert.. I sort of doubt the generator has the
capability to raise the bus voltage high enough to damage anything, but
I
could be wrong.
If the system is actually pretty standard, find a mech to take a look at
it.
Is the airplane a Tailwind (random shot - I couldn't think of any other
OBAM
aircraft that have O-300's)?
Good luck. Keep us posted..
Regards,
Matt-
--
No virus found in this incoming message.
--
Message 21
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--> AeroElectric-List message posted by: "Mike Larkin" <mlas@cox.net>
How long did the system work until it failed or started giving you
problems? Does the problem happen on both com radios the same way?
If so I think you are on the right track, it sounds like it is the audio
panel (PMA 7000). Give PS-Engineering a call and see if this is a
common problem. There are good people at PS-Engineering.
Mike Larkin
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Ron
Raby
Subject: AeroElectric-List: ptt problem
--> AeroElectric-List message posted by: "Ron Raby"
<ronr@advanceddesign.com>
To everyone:
I am having a problem with my push to talk on the pilot side. On the
ground
and for a while during flight the push to talk works fine. It then stops
working. The copilot side works fine. The parts involved are the PS
engineering pma 7000, approach systems hub, approach system cables,
Garmin
530 and an SL30.
I have rang out the cables directly up to the pma 7000. I cannot find a
problem. I have rang out the switch both when it is working and not and
it
is ok. I have shut of the intercom during flight and it still does not
work.
my gut feeling is something is not working in the pma 7000 when it gets
warm. Ideas would be appreciated.
Thanks
Ron Raby
Lancair ES
flying
----- Original Message -----
From: "Mickey Coggins" <mick-matronics@rv8.ch>
Subject: Re: AeroElectric-List: Re: Fresh approach
> --> AeroElectric-List message posted by: Mickey Coggins
> <mick-matronics@rv8.ch>
>
>> ... I have endured the same reception from
>> people in several internet chat rooms on my auto engine conversion.
>> Virtually
>> all claims my powerplant wouldn't work came from arm chair engineers
and
>> nay
>> sayers who couldn't take apart a ball point pen.
>
> Ben,
>
> As I learned in my high school chemistry class, "the universe is
> entropy". It's much easier to tear things down than to
> build them up.
>
> Your engine package looks very slick. I love the photo on your
> site where it looks like the VP is trying to get you trade aircraft.
>
> BTW, do you have your wiring schematic somewhere up where I
> can check it out? I assume your engine is electrically dependent,
> like mine. I'm always interested in looking at how others have
> done it.
>
> Thanks,
> Mickey
>
> --
> Mickey Coggins
> http://www.rv8.ch/
> #82007 Wiring
>
>
>
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Message 22
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--> AeroElectric-List message posted by: "Chris Horsten" <airplanes@sympatico.ca>
Thanks Mike,
That's one thing no one has thought of yet.
Chris
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Mike
Larkin
Subject: RE: AeroElectric-List: Help!
--> AeroElectric-List message posted by: "Mike Larkin" <mlas@cox.net>
I'm thinking ignition noise from a bad plug lead could be your problem.
Mike Larkin
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Chris
Horsten
Subject: RE: AeroElectric-List: Help!
--> AeroElectric-List message posted by: "Chris Horsten"
<airplanes@sympatico.ca>
Hi Matt,
Thanks for this hints
It's a Zenith CH-250. A further report from the ferry pilot reveals that
there is power. Radio is good during a message received, but reverts to
static once it ends. I will advise them re the TX as they probably don't
know that (I didn't). The aircraft was running perfect up until now. No
known issues. We did switch out the encoder about a week ago because the
last one seemed bad.
Re voltage being low I don't think this is the problem. Something is
generating some noise, because even the hand held is acting up and it is
operating on its own power. Engine is running fine and was started up at
least twice for a circuit after the problem surfaced. They are handing off
to a mechanic this am I believe.
Other possible sources: Master relay? Noise filter (capacitor)? Voltage
regulator?
Chris
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of mprather
Subject: Re: AeroElectric-List: Help!
--> AeroElectric-List message posted by: mprather <mprather@spro.net>
Random questions and comments:
If it were the brushes, I would guess that there would be some warning
symptoms. I have had alternator brushes go bad before, and normally, the
alternator light starts to flash occasionally, or just at start up.
Finally it gets bad enough that the battery is not getting charged, and then
is dead.
Is this airplane new, or new to your friend? I am wondering about pre
existing, but undisclosed problems, like maybe the charging system never
actually worked, but the seller sent them on their way with a charged
battery. Now maybe it's low?
Does the engine crank okay with battery power?
Do the stranded folks have any diagnostic instrumentation at their disposal?
It would be helpful if they either have a panel mounted volt/charging meter,
or even better, if they have access to a multimeter. Check the battery
voltage with everything turned off, then again with the engine running.
My Narco transponder light stays on solid for the first few minutes of
operation (I assume during warmup). I wonder if they have left the txp on
long enough to warm up.
I also wonder if bus voltage is so low that the com radio is having problems
operating.
I am not a generator expert.. I sort of doubt the generator has the
capability to raise the bus voltage high enough to damage anything, but I
could be wrong.
If the system is actually pretty standard, find a mech to take a look at it.
Is the airplane a Tailwind (random shot - I couldn't think of any other OBAM
aircraft that have O-300's)?
Good luck. Keep us posted..
Regards,
Matt-
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Message 23
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--> AeroElectric-List message posted by: "Ron Raby" <ronr@advanceddesign.com>
Mike
It happened on the first flight, and the same thing on both radios. PS eng.
allready said they would take it back an check it out. I am just trying to
eliminate anything I may have missed before I send it back
Thanks
Ron Raby
----- Original Message -----
From: "Mike Larkin" <mlas@cox.net>
Subject: RE: AeroElectric-List: ptt problem
> --> AeroElectric-List message posted by: "Mike Larkin" <mlas@cox.net>
>
> How long did the system work until it failed or started giving you
> problems? Does the problem happen on both com radios the same way?
>
> If so I think you are on the right track, it sounds like it is the audio
> panel (PMA 7000). Give PS-Engineering a call and see if this is a
> common problem. There are good people at PS-Engineering.
>
> Mike Larkin
>
> -----Original Message-----
> From: owner-aeroelectric-list-server@matronics.com
> [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Ron
> Raby
> To: aeroelectric-list@matronics.com
> Subject: AeroElectric-List: ptt problem
>
> --> AeroElectric-List message posted by: "Ron Raby"
> <ronr@advanceddesign.com>
>
> To everyone:
>
> I am having a problem with my push to talk on the pilot side. On the
> ground
> and for a while during flight the push to talk works fine. It then stops
>
> working. The copilot side works fine. The parts involved are the PS
> engineering pma 7000, approach systems hub, approach system cables,
> Garmin
> 530 and an SL30.
>
> I have rang out the cables directly up to the pma 7000. I cannot find a
> problem. I have rang out the switch both when it is working and not and
> it
> is ok. I have shut of the intercom during flight and it still does not
> work.
> my gut feeling is something is not working in the pma 7000 when it gets
> warm. Ideas would be appreciated.
>
> Thanks
>
> Ron Raby
>
> Lancair ES
> flying
>
Message 24
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--> AeroElectric-List message posted by: "Jerry Grimmonpre" <jerry@mc.net>
Eric Ruttan ...
You seem to be on to something here and the tone of your note is solid and
well meaning ... what is the message the reader should capture?
Confused in Illinois ...
Jerry Grimmonpre
----- Original Message -----
From: "Eric Ruttan" <ericruttan@chartermi.net>
Subject: AeroElectric-List: Dear Bob;
> --> AeroElectric-List message posted by: "Eric Ruttan"
> <ericruttan@chartermi.net>
>
> Dear Mr. Nuckolls;
>
> Last time I commented on this topic a very well known engineer ran away
> and
> did not come back for months. I do not desire a repeat of that but I
> think
> there are some problems that have not been addressed.
>
> It is with deep personal respect for your thinking process and work ethic
> I
> send these comments.
>
> From: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
>
>> .pdf's are most acceptable but I'll work with crayon on toilet paper
>> if necessary. If you're offering the next greatest thing, let's get
>> it out there for folks to exploit. I've hidden nothing, you've
>> revealed nothing.
>>
>> Bob . . .
>
> "I've hidden nothing, you've revealed nothing."
> This is the single point I have perceived from the very beginning of this
> discussion months ago. Claims are made. Ideas are shouted. But not a
> single simple idea critique has been proposed. Not a single, real world,
> valid critique, of any Z diagram has been made. Not single actually
> verifiable experiment or test has been shown in support of this
> "critique".
> In fact you have done experiments in response to these vague claims to
> quantify an area of these vague claims as not valid.
>
> Bob, at what point do you stop repeating yourself and realize your request
> for clarification is not being addressed? At what point to you stop doing
> work to disprove or quantify accusers unsupported and vague claims? When
> should they be responsible for SUPPORTING data behind a critique, OR EVEN
> CLEARLY ARTICULATING said critique?
>
>> And you've probably discovered, it's very USEFUL to have
>> conversations
>> with others who understand the role of good critical design review .
>> .
>> . they
>> are invaluable resources for thinking EVERYTHING trough. It's a
> win-win
>> . . .
>> either good ideas are deduced as sound and bad ideas are prevented
> from
>> going into production.
>
> I totally agree in the value of peer review. Bob, let me humbly suggest
> this is not what is happening here. What I see is a vague and changing
> critique of a well proven design. I see no clear articulation of simple
> ideas or raw data to suggest we can even begin to determine what the
> critique is. How can a discussion occur when peer reviewer will not
> clarify
> to a "simple idea" the critique? I see you, Bob, having a discussion with
> what you think they mean. I see you building an experiment showing an
> entire area of these vague claims are not supported in your experiments.
>
> The response to your experiment was to ask about parts, not get into the
> lab
> and repeat it. Bob, what does that mean to you? It holds great meaning
> for
> me.
>
>> > Chin up Bob.
>>
>> Thank you. This isn't a battle to be won or lost. It's an arena of
> ideas
>> wherein every idea should be evaluated for suitability to task.
>
> In your world it is an arena of ideas. But you are in the arena with
> someone who wont share/talk about/quantify ideas. If that is true, and it
> may not be, then I suggest you question your premise about where you are.
>
>> The hard
>> part is defining "task" and "suitability" in real numbers and failure
>> mode effects analysis and then fitting that to the marketplace.
>
> Bob, task is not hard. This "peer" discussion has refused to even
> addressed
> task.
>
> I cut your response to Eric's post. It also takes us down the same path.
> Eric is a very bright guy. He knows that saying "I would do this" is
> useless. It is the "because" that matters, which for some reason is
> missing
> from his post.
>
> Again I thank you for your time.
> Eric
Message 25
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| Subject: | Day/Night mode for Digitrak or Pictorial Pilot |
--> AeroElectric-List message posted by: "Dan Checkoway" <dan@rvproject.com>
If you have a Digtrak or Pictorial Pilot, you might find this
interesting...if not, delete!
When I installed my Digitrak a while back, I wired it into my panel lights
dimmer. This was a mistake. The only usable setting at night in my opinion
is the DIMMEST setting. Any brighter than that and the LED display gets way
too bright. In my case, hooked to my panel lights dimmer, as I brightened
the panel, the Digitrak's display was really distracting (too bright).
The Digitrak and Pictorial Pilot really need an "inverse" dimmer (dim at
night, bright during the day). But that's way too complicated for me.
I recently installed the Pictorial Pilot (same exact wiring/connector), and
I finally got around to fixing this problem. My "solution" is really simple
and super cheap.
http://www.rvproject.com/20050329.html
I wired up a mini-toggle switch ("Day/Night"). In the "Day" position, the
wire is not connected, and the display is full bright. In the "Night"
position it gets +12V through a 22k resistor, and it's about as dim as
possible. I've flown at night with this and it is muuuuch better.
Anyway, I wanted to spread the word that a 22k resistor will do the trick
for minimum brightness. Current consumption is almost nil, so the resistor
rating doesn't even matter imho. I used a Radio Crack special.
Hope this helps,
)_( Dan
RV-7 N714D
http://www.rvproject.com
Message 26
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| Subject: | Re: Day/Night mode for Digitrak or Pictorial |
Pilot
04/04/2005 01:56:04 PM,
Serialize by Router on MailServ58-US/AUS/H/NIC(Release 6.5.1|January 21,
2004) at
04/04/2005 01:56:06 PM,
Serialize complete at 04/04/2005 01:56:06 PM
--> AeroElectric-List message posted by: "David E. Nelson" <david.nelson@pobox.com>
Sounds like a good application for a photocell/photoresistor to negate the
switch. Looks like RadShack has them listed as 'CdS Photoresistor Mukti Pak'
(276-1657). They don't advertise the resistive ranges but that can be fixed.
/\/elson
On Mon, 4 Apr 2005, Dan Checkoway wrote:
> --> AeroElectric-List message posted by: "Dan Checkoway" <dan@rvproject.com>
>
> If you have a Digtrak or Pictorial Pilot, you might find this
> interesting...if not, delete!
>
> When I installed my Digitrak a while back, I wired it into my panel lights
> dimmer. This was a mistake. The only usable setting at night in my opinion
> is the DIMMEST setting. Any brighter than that and the LED display gets way
> too bright. In my case, hooked to my panel lights dimmer, as I brightened
> the panel, the Digitrak's display was really distracting (too bright).
>
> The Digitrak and Pictorial Pilot really need an "inverse" dimmer (dim at
> night, bright during the day). But that's way too complicated for me.
>
> I recently installed the Pictorial Pilot (same exact wiring/connector), and
> I finally got around to fixing this problem. My "solution" is really simple
> and super cheap.
>
> http://www.rvproject.com/20050329.html
>
> I wired up a mini-toggle switch ("Day/Night"). In the "Day" position, the
> wire is not connected, and the display is full bright. In the "Night"
> position it gets +12V through a 22k resistor, and it's about as dim as
> possible. I've flown at night with this and it is muuuuch better.
>
> Anyway, I wanted to spread the word that a 22k resistor will do the trick
> for minimum brightness. Current consumption is almost nil, so the resistor
> rating doesn't even matter imho. I used a Radio Crack special.
>
> Hope this helps,
> )_( Dan
> RV-7 N714D
> http://www.rvproject.com
>
>
--
~~ ** ~~ If you didn't learn anything when you broke it the 1st ~~ ** ~~
time, then break it again.
Message 27
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| Subject: | Re: Fresh approach |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
----- Original Message -----
From: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
Subject: AeroElectric-List: Re: Fresh approach
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
> <b.nuckolls@cox.net>
>
> At 01:17 PM 4/3/2005 -0700, you wrote:
>
>>--> AeroElectric-List message posted by: "Paul Messinger"
>><paulm@olypen.com>
> or complex?
>
>>The more
>>complex the design the more likely of failure and or improper pilot usage.
>>Having a "after failure of the alternator" multipart reconfiguration check
>>list is not a good idea in my opinion (as I recall Bob's design needs up
>>to
>>6 steps to reconfigure for emergency ops).
>
> Absolute BS Paul. Describe your perceived emergency checklist for
> emergency ops on ANY system described in the 'Connection . . . no,
> let's limit it to Z-13. If a low voltage light comes on, what is
> your perception of pilot response that take more than three steps?
I got the long list of steps from a post you made last fall discussing the
switching process when the alternator failed and it was necessary to turn
off things and switch to the emergency??? bus that is directly connected to
the battery. It was 5-6 steps as I recall. Its not worth it to me to go back
and pull the post out of the archives. NO BS but so what??
You said it, and others remember but so what? ANY check list is too much. I
am finishing the design of a system that requires NO action by the pilot. If
the battery fuel gauge says he has enough battery fuel with the current load
to get to a safe airport. Then the pilot can take optional actions to extend
the range and immediately see the results of turning things on or off. If
the pilot has tested the batteries and has installed quality batteries he
will have plenty of time to make decisions.
In your system there is NO means to tell how long you have on batteries
except trust as even the minimal current meter is not included.
You say use any battery but I have one of the "any" batteries that lost 2/3
of its AH in 2 years. If the pilot was counting on that battery he would
only have 1/3 the flight time left he was counting on. I think that is
unacceptable. You say to simple never check the battery AH and simply
replace the primary battery annually and take the one year old unchecked
battery and use it for the backup battery. Now we have a new but untested
battery in primary and a used untested battery in the backup position. I
have a sample of one where a 2 year old battery of that class having lost
2/3 of its AH. How much did it loose at the end of one year? Who knows. The
point is there is no way to tell what is left and clearly at 23 months and
28 days you may have far less ah than expect or need. With no way be sure
how fast you are now draining the batteries its possible you can end short
of the runway. I know of many cases of this on auto engine conversions. Sure
its important to be alerted that the alternator has failed but then its
critical to know how long you have left to fly. NONE of your designs and
recommendations supports knowing, they all are based on trust.
> You pushed aside a DEMONSTRATED current limit of under 260 amps for
> a crowbar event and insisted that events in the 400A to 700A range
> exist. Tell me how to duplicate your measurement or drop it.
I have posted at least twice the details of my test that resulted in 400
amps.
If you took the time to do a worst case analysis you would see that how it
is possible that more than 400 amps can occur.
I repeat for the third time! My battery setup was dual PC625 with a combined
internal resistance of 3.5 milliohms. My CB has a measured resistance of 10
milliohms ( the CB spec only specifies the max not the min and I have 3 that
range from 10-12 milliohms) I have approx 4 ft of #4 and 5 ft of #6 wire to
and from the CB and local ground ( I would have to go and measure exactly
but its copper lugs to copper lugs except at the battery where its brass to
copper. The CB buss is a bussbar connected to the #6 wire. Your OVP module
has 1" leads as its directly across the CB. ALL bolted connections. (Short
circuit battery current greater than 3600 amps).
Bottom line is that any test or even 100 different tests will never
determine the possible range of results.
> You make statements that ARE YET to be described in any repeatable
> experiment
Pure BS as you say. That you have not run my test with my specific parts IN
NO WAY MEANS THE TEST IS NOT REPEATABLE.
Perhaps I do not understand your definition of repeatable? Surely you do not
mean any 5 amp CB will give the same results. In collage we had experiments
and each set of equipment was identified as part of a specific set and in
that case the results were repeatable but varied quite a lot from one
students kit to another When you wrote up the lab report it was critical you
includes the kit serial number.
Your experiment is repeatable but change your batty or change the wiring or
the CB and you will get different results that are repeatable with that
specific configuration
MY tests was run dozens of times and witnessed others including my peers who
were able to properly evaluate the setup. The equipment was Tektronix in
calibration. That you have not seen that test is not relevant. I did not see
your test but I respect your data as you should respect mine but that seems
to be a fantasy.
yet you push aside my fully described and published experiment
> by claiming that I have made some conclusion based on a single test which
> represents no type of engineering you respect. This was in spite of the
> fact that no conclusion was made. I did the work, gathered the data,
> hypothesized a 250A max limit (installed systems run much lower) and
> you have yet to tell me where that experiments was bad . . . respectable
> or otherwise.
More BS facts not in evidence. My test was directly modeled from the wiring
in MY aircraft.
You did make a conclusion and even in this post you say that installed
systems run much lower. How can any person believe that? How many installed
systems have you looked at and measured?? Surely not mine where I used good
engineering methods to reduce the wiring voltage drops to the CB panel.
If you would do a worst case analysis using all possible part variations you
would see how easy it is to get 400 amps. Use my battery, wiring and CB
resistances its not hard to run the numbers.
Lets see, I measured under 0.020 ohms battery + to battery - (that is actual
not the estimated listed above wiring and CB in series). So if the battery
terminal voltage under load dropped to 8 V that makes the load current 400
amps. Perhaps that is maximum possible but my having 3 CB's in the 10-12
milliohm range is that the absolute minimum resistance? The actual battery
internal resistance is not specified just that the short circuit current is
specified to be greater than 3600 amps in this example of 2 in parallel.
Math department. External battery load resistance (measured) 0.020 ohms. 400
amps current V=IR so 0.020 x 400 = 8 V battery terminal minimum required.
Actual battery terminal voltage was higher indicating the real internal
resistance was lower than the nominal value specified.
I mentioned I had one non repeatable 700+ amp test in a different
configuration. That test was not something I repeated as it was not a
reasonable wiring configuration but the 400 amp case was.
BUT so what even 200 amps is out of line with good engineering practices and
not necessary with the addition of a series resistor or a different approach
to opening the "B" lead.
I guess your definition of repeatable test is different from mine. The test
is repeatable only if the same identical parts are used. Not the same part
numbers, the identical parts. If I shipped to you my complete test you would
find it repeatable
>
>>Why worry about faults that are as likely as prop bolt failures?
Exactly and I suggest that a hard failure of the alternator field is very
rare. Breaking the "B" lead in that case may weld the contacts on opening
and you end up with no separation of the alternator. If the regulator
failure is simply HI output the current/voltage is controlled and the
voltage across the contacts are lower and the opening arc is very likely to
simply go out.
I know of no testing where the field is connected directly to the "B" lead
and then the load and rpm is varied to see what any specific alternator
does. While such testing might give us a general idea of what happens its
not valid to conclude that all alternators will perform the same way and as
we use different brands the results will even less indicative or what might
happen.
As above I have shown that battery voltage can be 8 v and that can be what
the "B" lead sees during the OVP event depending on how the wiring is
physically connected. The voltage at the CB is thru mostly different wiring
that the "B" lead wiring so V drops to the CB are not the same.
8 V is more than enough when you consider the alternator field is directly
connected internally to the alternator to the "B" lead. With a shorted to
ground regulator that puts full voltage to the field and soon as the OVP
event trips the CB the OVP load is removed and immediately the alternator
output V is only held down by the battery while the slow opening of the "B"
lead contactor is in process. Given your test with a 15 ms OVP CB opening
and the contactors opening time of 50 ms (with a diode across it) there is
plenty of time for the alternator to recover and make contact opening a
firey event. If I can remember you stated that you were not sure the
contactor contacts could take it. On that WE agree.
The failure of the internal regulator in a hard short mode which results in
the burnout of the alternator is exceedingly rare. I only have heard of one
in the last 20 years and none were ever noted by local alternator and auto
shop personnel. Its extremely rare, just that if it happened it can be bad
news. But so can a prop failure which is reported much more often. Failing a
little high is the second most common failure as the failure of no output is
99+% of the failures reported locally.
Do we know if any failed high but not shorted outputs loose control of the
field control??
Perhaps its a simple opening of the field control lead is all that is
needed.
The simple alternator regulator going a little high and the OVP tripping is
a very different failure mode that is much easier to deal with. AN OVP trip
may or may not even be the result of a failure. It could simply be a false
trip. I and others have been told by dozens of builders that they have
scrapped the OVP module because of false tripping. AS you agreed its
possible to false trip simply from excessive contact bounce when switching a
heavy load as I found in the Load dump testing (Yes you agreed in one post
here) where the false trip was 100% of the time until I added a large
capacitor across the OVP 10 mfd was not enough and I ended up with 1000 mfd
to eliminate false tripping. The OVP still worked as I would have expected
it to but only in the case of true OV. Any OVP module we install on the
aircraft must NOT false trip. Its easy to design one that does not false
trip and one that does not crowbar with large currents (two different
concepts).
If you review experimental prop failures you will find prop bolt failure
(not fracture as much as loosening) has killed people. In one case it was a
family of 4.
The feedback in
> received from you has only generated a need to address your concerns
> by going to the manufacturers and other spec sources.
I am only pointing out over and over that designs need to be done with
respect to the specifications as a parts ratings are not determined by test
and ignoring (or overlooking a limitation in the data sheets).
In the engineering world I come from the engineer that designed the circuit
must defend it. You have turned it around and said prove me wrong. You have
simply gotten it backwards. I say your OVP design as a module its self over
stresses parts when installed in a possible aircraft configuration. Its up
to you to show its not possible to overstress it.
But clearly that is never going to happen.
Perhaps you can show us ANY case where the crow bar approach has been used
to directly short a large battery supply. I have found no such application
and all my peers have never heard of one either. Its simply a misapplication
that my peers all agree on. The crow bar has its place but no one I know has
ever seen it used this way.
I am going to respond to a few previous incorrect statements you have made
about me but if you truly want to stop this exchange simply stop your
replies. I will not continue the debate over things like the "need to design
within the specifications" and "worst case analysis" as clearly we do not
agree and its confusing the rest of the list. Also your OVP is off limits by
me from future posts. We will never agree.
Paul
Message 28
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| Subject: | Re: OVP etc - do we have a bottom line? |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
----- Original Message -----
From: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
Subject: Re: AeroElectric-List: OVP etc - do we have a bottom line?
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
> <b.nuckolls@cox.net>
>
>
>>
>>The CB max no damage current rating is a personal concern to some and not
>>a
>>big deal IF you have a real event as the alternator has failed. replacing
>>the CB may or may not be needed. A purest will replace it most will simply
>>press on by resetting. My objection is it does overstress the CB and a
>>good
>>design of OVP would limit the current so there would be no question.
>
> The data I'm getting so far does not support the "no damage"
> interpretation
> of the specification cited . . . but that's a study in process.
My point is the spec says it may no longer meet spec. It does not say in
what parameters are out of spec. Until the spec is revised with more detail
the engineers I have worked with would never operate the device out of
spec.... To me out of spec clearly means damage. It might mean contact
resistance or lifetime etc but we have no way of knowing and unless the spec
is clarified in writing by the manufacturer we have no choice but to not
violate the spec. As its simple to modify the circuit to meet spec why even
spend the time to get the 3 or 4 manufacturers to clarify in writing what
happens. My guess is you will never get anything in writing beyond perhaps
an engineers opinion.
What is so hard about adding a current limiting resistor? I simply do not
understand your apparent resistance.
The worst thing to happen to current installations is the potential need to
replace the CB in the event of an OV event. If there is a valid OVP event
the owner already needs to replace the alternator so it not that big a deal.
That is on OBAM acft. Certificated aircraft is a different case where I am
being told its mandatory to replace the CB is the LR-3 trips.
>> I have a documented case of
>>certificated aircraft having major compass errors accumulating over time
>>with currents around 50 amps max passing 18" away from the compass so it
>>can
>>be a concern (The mandatory service bulletin to correct this problem will
>>be soon posted here for all to see).
>
> Whoa! Where does that come from? This issue has been addressed
> years ago and improved upon when b-leads were taken out of the
> cockpit and bus bars were moved off the panel into fuse blocks.
> Just about EVERY airplane has a placard saying that the compass
> is calibrated with certain things ON or OFF. There are demonstrated
> concerns and techniques involving wires carrying high static current
> loads since the first generator went into an airplane. So what's that
> have to do with a crowbar ov event? Every time you crank the engine
> you have a 500-1000 amp event, why do we not agonize over that?
Its not the currents, its the location of the wiring. Mooney released a
Mandatory Service Bulletin M20-150A that addressed the need to relocate the
wire feeding the aux CB panel. It even required the elimination of the
remote grounding of the recognition light wiring in the wings by replacing
the single wire grounded at the tip with a twisted pair grounded at the main
ground point. Over kill perhaps but as there were mod kits made available I
suggest the modifications had merit.
We are looking at a gradual increase in the compass error of 30 deg or more.
I know the owner who is a IA who had that happen on his aircraft and had a
30 deg error from the simple over time of the current flowing from the left
to the right side of the panel. The compass was 1/2 way up the windshield.
He complied with the bulletin and the problem has not recurred in 35 years
I am not talking about the need to swing the compass with specific things
ON, this was a permanent change over time from the electric field
magnetizing the steel tube inner structure. The currents were well under 50
amps and had nothing to do with starting. Also this was manual gear aircraft
so there is only the starter and alternator that produce large currents and
with the battery ahead of the firewall there was nothing like you suggest to
generate large currents. All starting and alternator wiring was ahead of the
firewall along with the battery and the specific cause was mostly the wire
from the left side of the panel to the right connecting the main power to
the aux CB panel for things like avionics etc.
My concern is we are now installing avionics that may contain very sensitive
magnetometers and even 50 amps can be a problem. Having a steel tube cockpit
only increases the need to be very careful in wire routing. There are some
popular OBAM acft with steel tubing like the Glastar.
>
> I had to chase a rat out of the woodpile on Bonanza compasses that
> didn't like having the SD-20 alternator turned on . . . on the OTHER
> side of the firewall . . . we went to the alternative compass location
> on the windshield. Yes, every airplane has issues of electrically
> induced magnetics but none of those issues are foundation for
> dismissing the value or utility of a crowbar ov protection system.
>
>
>>If you have a RV with Van's alternator add the recommended Transorbs and
>>consider using Erics OVP approach. If you have the Aeroelectric OVP any
>>false trip is unlikely to be a problem to the alternator with the added
>>Transorbs.
>>
>>There is little probability of problems with the B & C conversion using
>>the
>>LR-3 regulator but adding "B" 'lead transorbs are recommended by both Eric
>>and myself on all alternators.
>>
>>If you have a Glastar or other aircraft with a steel tube inner or outer
>>cabin structure I would NOT use Bob's OVP module simply due to the poor
>>effects of HI currents in the cabin. IE careful wiring and transient
>>currents in the 50 amp or above might be hazardous to your flight
>>instruments and as a minimum a compass accuracy check on an annual basis
>>is
>>recommended.
>
> Unmitigated BS Paul . . .
True (not BS) and see my above comments on the case of Mooney. I am tired of
your comment about BS when you simple do not like the truth or a valid
opinion backed by Facts! I base my comments on industry documents (l have
posted in the past) and it would be nice if you asked for references and not
simply say its BS when its clearly not and I can back it up.
Its widely know that its very easy to magnetize steel and 4130 is no
exception. The small field form a steel tube can and does often effect a
compass a couple of feet away. In this case it was cumulative from currents
over time where the currents were relatively small. Not at all like the
direct effect of current where there is no lasting effect.
There are far too many cases of your simply saying it is BS for me to
continue most any discussion with you given your apparent closed mind. How
about the widespread use of simple diodes across relay coils?? When the
relay industry in the US and Europe (as an example) says that is not the way
to do it. I am sure that I would have gotten a BS comment If I have not
posted proof than the simple diode was not the best way but actually
encouraged contact welding on opening due to the slowing down of the opening
speed. You have often stated that the speed of opening is not slowed once it
starts but industry says you are wrong. Just as you are wrong in saying
diodes are the way to clamp transients across the relay coils. If the coil
was the only concern I might agree but the potential damage to the contacts
is equally important. Thus the relay industry says do not use a simple
diode.
>>In conclusion;
>>
>>There is simply no one size fits all that is safe to use. Most of the
>>builders are safe with the externally regulated LR-3 setup. some will be
>>unsafe with the use of Bob's OVP module and many are in the middle.
>
> How "unsafe" . . . are we talking about hazard to equipment or
> hazard to people?
Hazard to equipment and that may result in hazard to people. If the compass
heading is in error from the above case it can be hazard to people. If the
magnetometer inside a piece of avionics is damaged or the calibration is
shifted it may be hard to detect and expensive to fix.
My point is not necessary to have the large currents. I am mystified why
you insist high currents are OK and not redesign to lower currents.
>
>>However remember any who want to use the emergency mode of "No battery"
>>need
>>to know that both the LR-3 and the OVP module have a 100% chance of
>>tripping
>>the alternator off line with no battery and the often suggested addition
>>of
>>a 25,000 mfd capacitor to "stabilize the alternator regulator is by test
>>not
>>going to prevent false triggering of these devices from such simple things
>>as turning off landing lights or strobes or recognition lights if the
>>alternator is lightly loaded.
>
> I have yet to see any data that shows alternator only operations
> are compatible with the DO-160 suite of aviation products, much less
> those for which you're trying to craft a kinder and gentler electrical
> system. The dynamics of the voltage regulator's servo loop are "tuned"
> with a battery on line. If one desires a regulator optimized for
> no-battery operation, that can be supplied but to the present time,
> no one has asked for it.
Disagree that alternators need a battery. They do need some sort of load to
stabilize the output voltage and there is the load dump to consider and the
solution is simple.
The alternator regulator simply adds current to the field if the load
increases and stops current flow if the voltage is too high. There is no was
for a regulator to stop load dumps as the regulator has no control of the
output other than cutting field current. redesign of a regulator to clamp
load dumps is not a minor change as the regulator would need control of the
output side of the alternator which it currently does not have. But the
addition of proper transorbs is a simple thing to add to clamp the load dump
and VOLA you have a setup that does not need a battery for stable operation
Or at least the popular ND brand
This is not theory as flight tests have been made with no transorbs no OVP
crowbar and no capacitor. Flight testing including load dumps from landing
light cycling and no damage to any component. Not that this should be done
with out transorbs in normal operation but its a flight test of a real
aircraft as you seem to desire. (55 amp ND rebuilt alternator by Bosch as
the rebuilder).
Its been demonstrated many times that a 25,000 cap does filter much of the
load dump and acts as a ripple filter for the alternators switching
regulator. Its also been demonstrated that no cap will work IF you control
the load dumps with Transorbs. In fact you do not need the capacitor if you
have properly added transorbs.
The problem is the use of a quick acting OVP as in the LR-3 or the OVP
module is they cannot tell the difference between a load dump and a
regulator failure and that is why they need a battery. Thus my statement
that no battery operations is prevented if these or a similar fast acting
OVP is in the system, The use of a 25,000 mfd capacitor does not keep the
Voltage under the 16.x volts so the OVP trips. Eric and I have demonstrated
by test and analysis that a 200 MS delay in the OVP along with the use of
transorbs allows no battery operation while insuring a legitimate failure is
detected and action taken
>
>
>>No battery operation is my opinion a very important emergency mode of
>>operation.
>>
>>Here is what Bob has recently stated on this subject "but the question of
>>no-battery operation has never been addressed nor recommended in any of my
>>writings"
>>
>>I agree that none of his suggested schematic designs allow this mode
>>simply
>>because they all include a LR-3 or OVP module that triggers with a load
>>sump
>>(that Bob requires the battery to clamp).
>
> That was not the consideration at the the time. NOBODY but Barons
> and Bonanzas allows battery-less operation by manipulation of
> panel controls. There was a good reason for that long before the
> manner and style of ov protection was considered. To imply that
> I don't recommend battery-less operation just to satisfy some
> feature of the ov protection system is a presumption of facts
> not in evidence and patently untrue . . . I was there. I did it
> and I know the foundation upon which the system was built.
I know and certificated aircraft are not the issue here. I do not think they
ever were given the ability to change the basic electrical design under the
FAA regulations including batteries. Also what has been done in the past in
not at issue. Past times the engine ran fine with no electrons needed.
Today (and to for over 10 years) we have the need in some cases for large
currents (10-20 amps) to keep the engine running. I object to the lack of
the Aeroelectric connection not recognizing this and supporting this
emerging use of electrically dependent engines There are thousands of auto
conversions flying today and this is not new as the numbers have been
growing over the last 15 years. This is nearly always a OBAM aircraft and
yet today there is no electrical system design that meets that need
properly.
>
>
>> No battery, no clamp, first event
>>and alternator trips off line and no electrical power.
>
> Neither the LR-3 nor the OVM-14 was designed to accommodate the
> battery-less system. They COULD be . . . the first question that needs
> to be address is whether battery-less operations are broadly practical
> and therefore recommendable. If that proves to be useful, a suitable
> regulator and ov protection system can be designed for that service.
> Please don't imply that the products presently offered are somehow
> evil because they don't meet requirements not in place when those
> components were designed.
I have demonstrated by test and others have demonstrate by flight that
current alternator regulators will work properly with the use of load dump
controls WE do not need a new type of alternator regulator just a load dump
control (extremely simple) and a different type of OVP (commercially
available right now from Eric Jones and its been tested to verify it truly
works)
>
> If your suggesting a new environment, get it out there on paper
> and let's explore the numbers. See my other posting.
Nothing beyond what I have already posted. Add load dump control and a time
delay OVP and you are there; Both are a matched set as the Load dump
transorbs need to be matched to the alternator so they are not overloaded by
the end of the OVP time out (if the failure is real and not a simple load
dump).
Tested extensively and backed up with analysis. As you often say If you do
not believe me do some analysis and post where I have gone wrong. I have
both analysis and real tests to back up the analysis.
However I have not studied the external regulator approach much as its
easier to go with the flow as internal stock auto alternators are the wave
of the future in OBAM. If I can get a brand new or quality rebuilt
alternator for $200 to $300 why would I even consider the B & C nearly
$1,000 approach. Even more important in the case of away from home failures
the local auto store likely has a replacement in stock (an important
consideration to many). There are at least 5000 OBAM acft flying with
internal regulators and no OVP modules. Foolish perhaps but its hard to
argue with the numbers. No known failure HI reported. Prop bolts anyone??
Paul
Message 29
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| Subject: | Well Bob you win |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
I cannot continue to spend the time when its clear we have such different
backgrounds and backgrounds of experience. There is simply no common ground
to a discussion.
In aerospace, "failure was not an option" so every design was subjected to a
detailed design review and the review package included a worst case design
analysis as well as a proof of concept, sample of one lab test. Design
approval was based on the worst case analysis demonstrating all component
variations resulted in parts stress of less that specified maximum so any
combination of parts would work and not be overstressed. Or even work as its
possible to have a single lab test work and production parts when assembled
fail to work. Happens more than some might think.
I have tried to reason and for a while I thought you were considering my
facts but that moment of sanity has past and you are back in the old mode
Bob is so famous for.
Just as one cannot test reliability in to a product:
You cannot test a bad design into a good one.
You cannot sample the population with one sample and get meaningful results
etc etc.
This is the only place where a single test is suffient to justify the design
is good.
I have never experienced a case where the designer not only had never done a
worst case analysis but clearly had no intention of doing so. This is based
on a partial worst case analysis I performed showing any part combination
would not work.
We have gotten into a debate and lately you have resorted to name calling to
the extent most of the list readers are confused and the original facts are
buried in reply's to reply's.
I have many more relevant things to bring up that potentially can effect how
OBAM aircraft are electrically wired but its clear that I am wasting my
time.
I have a real contract with a real player in the experimental engine market
to advance the state of the art. That is where I will be spending my time as
our debating is a huge waste of my time.
For those who may think I am an air head as Bob would like you to believe I
have enough commendations and awards for performance and technical
excellence to paper a hanger door and have paper left over.
How else would I win such a contract for a new generation of aircraft
electrical systems??
I have many posts that need reply's but they will simply not be posted this
is truly the end.
Any who want to ask me something must email directly to me.
Paul
Message 30
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| Subject: | Re: RAC Trim noise |
--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
--> AeroElectric-List message posted by: Gilles Thesee
<Gilles.Thesee@ac-grenoble.fr>
>Nevertheless would a capacitor across the trim motor wires improve things ?
> Probably. Try 1000 pf ceramic capacitor across motor leads (white wires).
>Bob,
Gilles,
Even better---open up the case and add a 0.01 uF cap across the two
terminals on the motor. Then a 0.01 uF cap from each terminal to ground (if
available). This is easy to do.
I've never seen anyone discuss changing the motor and/or brushes in the
MAC/RAC trim boxes, but they certainly can't last forever--and when the
motor brushes wear out they make a lot of electrical noise just before
becoming very very quiet.........So don't squash the noise before you find
out if it might be trying to tell you something.
I think in general that unexplained EMI/RFI noises should make one put motor
brushes on the short list of possibilities.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
Phone (508) 764-2072
Email: emjones@charter.net
Message 31
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| Subject: | Re: RAC Trim noise |
--> AeroElectric-List message posted by: Gilles Thesee <Gilles.Thesee@ac-grenoble.fr>
Eric,
Thank you for responding.
>Even better---open up the case and add a 0.01 uF cap across the two
>terminals on the motor. Then a 0.01 uF cap from each terminal to ground (if
>available). This is easy to do.
>
>
>
Open the case, hmm, my buddy is going to frown upon that...;-) I'll try
to convince him.
>I've never seen anyone discuss changing the motor and/or brushes in the
>MAC/RAC trim boxes, but they certainly can't last forever--and when the
>motor brushes wear out they make a lot of electrical noise just before
>becoming very very quiet.........
>
The trim unit has 17 hours on it since new, and it is seldom used in flight.
Regards,
Gilles
Message 32
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Received-SPF: softfail (mta6: domain of transitioning trigo@mail.telepac.pt does
not designate 85.138.31.240 as permitted sender) receiver=mta6; client_ip=85.138.31.240;
envelope-from=trigo@mail.telepac.pt;
| Subject: | Re: OVP, grounds, resistive loads |
0.60 COMMA_SUBJECT Subject is like 'Re: FDSDS, this is a subject'
--> AeroElectric-List message posted by: "Carlos Trigo" <trigo@mail.telepac.pt>
AeroElectric-List message posted by: Christopher Stone <rv8iator@earthlink.net>
.......
2. I am using a single point ground for all grounds per above description. Z-13
shows a firewall ground, instrument ground and avionics ground. I don't see
any reason not to combine all these to a single point. Am I missing something?
3. Pure resistive loads (heater elements)should not be a source of electrical
noise. That said, I am locally grounding the pitot heat and seat heaters. Again,
am I missing anything here?
4. The wire feeding the main bus is shown unprotected. In my ship this is four
feet of AWG 6 that goes from the bat side of the starter contactor to the main
fuse block. I realize that turning off the master turns this off, but a
short to ground along this wire run could be disastrous! Do I need to be concerned?
......
I appeal to the experts of this list to please answer Chris Stone's questions,
because I am also very interested on the answers.
Carlos Trigo
Message 33
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| Subject: | Re: OVP etc - do we have a bottom line? |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 01:35 PM 4/4/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
>
>
>----- Original Message -----
>From: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
>To: <aeroelectric-list@matronics.com>
>Subject: Re: AeroElectric-List: OVP etc - do we have a bottom line?
>
>
> > --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
> > <b.nuckolls@cox.net>
> >
> >
> >>
> >>The CB max no damage current rating is a personal concern to some and not
> >>a
> >>big deal IF you have a real event as the alternator has failed. replacing
> >>the CB may or may not be needed. A purest will replace it most will simply
> >>press on by resetting. My objection is it does overstress the CB and a
> >>good
> >>design of OVP would limit the current so there would be no question.
> >
> > The data I'm getting so far does not support the "no damage"
> > interpretation
> > of the specification cited . . . but that's a study in process.
>
>My point is the spec says it may no longer meet spec. It does not say in
>what parameters are out of spec. Until the spec is revised with more detail
>the engineers I have worked with would never operate the device out of
>spec.... To me out of spec clearly means damage.
. . . not necessarily. Take a 10A switch and operate it at
15A . . . catastrophic damage or reduced service life? Yes,
I see those curves lopped off very neatly at 10X of breaker
rating and the data which says the breaker is rated for so
many killobreaks . . . so suppose I operate it at 15x or even
50x . . . are we talking about catastrophic damage wherein
the device will fail to function or are we shortening service
life? As an component of a system that won't be called upon to
operate more than a few times in the lifetime of the airplane, the
notion of operating a 5A breaker with 200A trip currents and reducing
life from 2500 to say 200 operations doesn't bother me.
> It might mean contact
>resistance or lifetime etc but we have no way of knowing and unless the spec
>is clarified in writing by the manufacturer we have no choice but to not
>violate the spec. As its simple to modify the circuit to meet spec why even
>spend the time to get the 3 or 4 manufacturers to clarify in writing what
>happens. My guess is you will never get anything in writing beyond perhaps
>an engineers opinion.
If I cannot get a clarification in writing, then the spec is useless
and I have to depend on my own verification of that particular feature.
Charles Kettering was mightily castigated for proposing that one
could drag 2 hp out of a .1 hp motor for a few seconds at a time
in order to get an engine started. He was operating the motor way
of out specification for continuous duty cycle on a motor that might
have a .1 hp service life of hundreds of hours. Yes, if he overloaded
the thing for 10 seconds per start and reduced the service life to
10 hours total, that's still 3600 starts for the lifetime of a
BLOWER motor pressed into STARTER service. So while his contemporaries
said it couldn't be done because a starter motor would have to be
a foot in diameter and 2 feet long, he showed how to design for
controlled overloading of a device to achieve a different result.
>What is so hard about adding a current limiting resistor? I simply do not
>understand your apparent resistance.
A goal of my spec for creating the the crowbar ovm in the first
place was to REDUCE field drive voltage to the lowest possible value
even before the breaker opened. We did a lot of testing that showed
the approx 2 volt ON-voltage for the SCR drove toward that goal.
Therefore, for an internally regulated alternator, the commencement
of the shutdown event was not predicated on response time of the circuit
breaker. This feature impressed the folks at Beech a great deal and
we proved through our own and their independent testing that it
generated no electrical events outside the DO-160/Mil-Std-704 envelope
and was imminently certifiable.
When we expanded application of this technology into the internally
regulated world, the crowbar module was no longer able to act directly
on the alternator . . . opening time of the breaker was added to
opening time of the b-lead contactor in a situation where successful
breaking of the b-lead was dependent on the fastest possible response.
So, adding a resistor to pamper a breaker that may not need pampering
drives us away from the original design goals.
>The worst thing to happen to current installations is the potential need to
>replace the CB in the event of an OV event. If there is a valid OVP event
>the owner already needs to replace the alternator so it not that big a deal.
>That is on OBAM acft. Certificated aircraft is a different case where I am
>being told its mandatory to replace the CB is the LR-3 trips.
Find that in writing . . . I've already talked with the gray beards
at RAC, and one of the most capable and informed representativesw
at Eaton/Cutler-Hammer and nobody's ever heard of this requirement.
I can't find in in the FARS or advisory circulars I have.
> >> I have a documented case of
> >>certificated aircraft having major compass errors accumulating over time
> >>with currents around 50 amps max passing 18" away from the compass so it
> >>can
> >>be a concern (The mandatory service bulletin to correct this problem will
> >>be soon posted here for all to see).
> >
> > Whoa! Where does that come from? This issue has been addressed
> > years ago and improved upon when b-leads were taken out of the
> > cockpit and bus bars were moved off the panel into fuse blocks.
> > Just about EVERY airplane has a placard saying that the compass
> > is calibrated with certain things ON or OFF. There are demonstrated
> > concerns and techniques involving wires carrying high static current
> > loads since the first generator went into an airplane. So what's that
> > have to do with a crowbar ov event? Every time you crank the engine
> > you have a 500-1000 amp event, why do we not agonize over that?
>
>Its not the currents, its the location of the wiring. Mooney released a
>Mandatory Service Bulletin M20-150A that addressed the need to relocate the
>wire feeding the aux CB panel. It even required the elimination of the
>remote grounding of the recognition light wiring in the wings by replacing
>the single wire grounded at the tip with a twisted pair grounded at the main
>ground point. Over kill perhaps but as there were mod kits made available I
>suggest the modifications had merit.
Fine . . . do like we've all been doing for years . . . move the wiring.
I'm writing a change request tomorrow morning to move a wire from one
bundle to another in a 30 year old design to reduce a noise issue.
It seems better to figure out how all the big noises and tender ears
can be engineered to co-exist than to suggest that we should never
generate a big noise because it MIGHT injure tender ears.
>We are looking at a gradual increase in the compass error of 30 deg or more.
>I know the owner who is a IA who had that happen on his aircraft and had a
>30 deg error from the simple over time of the current flowing from the left
>to the right side of the panel. The compass was 1/2 way up the windshield.
>He complied with the bulletin and the problem has not recurred in 35 years
>
>I am not talking about the need to swing the compass with specific things
>ON, this was a permanent change over time from the electric field
>magnetizing the steel tube inner structure. The currents were well under 50
>amps and had nothing to do with starting. Also this was manual gear aircraft
>so there is only the starter and alternator that produce large currents and
>with the battery ahead of the firewall there was nothing like you suggest to
>generate large currents. All starting and alternator wiring was ahead of the
>firewall along with the battery and the specific cause was mostly the wire
>from the left side of the panel to the right connecting the main power to
>the aux CB panel for things like avionics etc.
>
>My concern is we are now installing avionics that may contain very sensitive
>magnetometers and even 50 amps can be a problem. Having a steel tube cockpit
>only increases the need to be very careful in wire routing. There are some
>popular OBAM acft with steel tubing like the Glastar.
Magnetometers have classically be placed as far from potential noise
sources as possible . . . out on wing tips, back in the tail cone,
etc. Anyone who puts a magnetometer on or near the panel should
consider his system integration design very carefully. This isn't
a new issue and probability of it becoming an issue is a combination
of poor systems integration.
> >>
> >>If you have a Glastar or other aircraft with a steel tube inner or outer
> >>cabin structure I would NOT use Bob's OVP module simply due to the poor
> >>effects of HI currents in the cabin. IE careful wiring and transient
> >>currents in the 50 amp or above might be hazardous to your flight
> >>instruments and as a minimum a compass accuracy check on an annual basis
> >>is
> >>recommended.
> >
> > Unmitigated BS Paul . . .
>
>True (not BS) and see my above comments on the case of Mooney. I am tired of
>your comment about BS when you simple do not like the truth or a valid
>opinion backed by Facts! I base my comments on industry documents (l have
>posted in the past) and it would be nice if you asked for references and not
>simply say its BS when its clearly not and I can back it up.
<snip>
>Its widely know that its very easy to magnetize steel and 4130 is no
>exception. The small field form a steel tube can and does often effect a
>compass a couple of feet away. In this case it was cumulative from currents
>over time where the currents were relatively small. Not at all like the
>direct effect of current where there is no lasting effect.
That's why I don't like for folks to ground their tail mounted
batteries to the airframe . . . but connecting the magnetized
fuselage steel and crowbar events as mutually risky to the compass
is a real stretch.
>There are far too many cases of your simply saying it is BS for me to
>continue most any discussion with you given your apparent closed mind. How
>about the widespread use of simple diodes across relay coils?? When the
>relay industry in the US and Europe (as an example) says that is not the way
>to do it. I am sure that I would have gotten a BS comment If I have not
>posted proof than the simple diode was not the best way but actually
>encouraged contact welding on opening due to the slowing down of the opening
>speed. You have often stated that the speed of opening is not slowed once it
>starts but industry says you are wrong. Just as you are wrong in saying
>diodes are the way to clamp transients across the relay coils. If the coil
>was the only concern I might agree but the potential damage to the contacts
>is equally important. Thus the relay industry says do not use a simple
>diode.
>
>
> >>In conclusion;
> >>
> >>There is simply no one size fits all that is safe to use. Most of the
> >>builders are safe with the externally regulated LR-3 setup. some will be
> >>unsafe with the use of Bob's OVP module and many are in the middle.
> >
> > How "unsafe" . . . are we talking about hazard to equipment or
> > hazard to people?
>
>Hazard to equipment and that may result in hazard to people. If the compass
>heading is in error from the above case it can be hazard to people. If the
>magnetometer inside a piece of avionics is damaged or the calibration is
>shifted it may be hard to detect and expensive to fix.
Anyone mouning a magnetometer inside a piece of avionics needs
to attend a really good critical design review to see that he
has not created the hazard you hypothesize. I wouldn't do it,
don't know why anyone else would if they want the best performance.
There's no magnetometers anywhere in the cockpit/cabin of any
airplanes we build.
> My point is not necessary to have the large currents. I am mystified why
>you insist high currents are OK and not redesign to lower currents.
For the reason cited. Letting the breaker operating time
drift upward in the internally regulated ov protection system
allows the alternator to get just that much more head start
on the b-lead contactor. I'm still not sure that the Cole-Hersee/
Stancor contactors will reliably serve in this function
> >
> > I have yet to see any data that shows alternator only operations
> > are compatible with the DO-160 suite of aviation products, much less
> > those for which you're trying to craft a kinder and gentler electrical
> > system. The dynamics of the voltage regulator's servo loop are "tuned"
> > with a battery on line. If one desires a regulator optimized for
> > no-battery operation, that can be supplied but to the present time,
> > no one has asked for it.
>
>Disagree that alternators need a battery. They do need some sort of load to
>stabilize the output voltage and there is the load dump to consider and the
>solution is simple.
>
>The alternator regulator simply adds current to the field if the load
>increases and stops current flow if the voltage is too high. There is no was
>for a regulator to stop load dumps as the regulator has no control of the
>output other than cutting field current. redesign of a regulator to clamp
>load dumps is not a minor change as the regulator would need control of the
>output side of the alternator which it currently does not have. But the
>addition of proper transorbs is a simple thing to add to clamp the load dump
>and VOLA you have a setup that does not need a battery for stable operation
>Or at least the popular ND brand
>
>This is not theory as flight tests have been made with no transorbs no OVP
>crowbar and no capacitor. Flight testing including load dumps from landing
>light cycling and no damage to any component. Not that this should be done
>with out transorbs in normal operation but its a flight test of a real
>aircraft as you seem to desire. (55 amp ND rebuilt alternator by Bosch as
>the rebuilder).
>
>Its been demonstrated many times that a 25,000 cap does filter much of the
>load dump and acts as a ripple filter for the alternators switching
>regulator. Its also been demonstrated that no cap will work IF you control
>the load dumps with Transorbs. In fact you do not need the capacitor if you
>have properly added transorbs.
>
>The problem is the use of a quick acting OVP as in the LR-3 or the OVP
>module is they cannot tell the difference between a load dump and a
>regulator failure and that is why they need a battery. Thus my statement
>that no battery operations is prevented if these or a similar fast acting
>OVP is in the system, The use of a 25,000 mfd capacitor does not keep the
>Voltage under the 16.x volts so the OVP trips. Eric and I have demonstrated
>by test and analysis that a 200 MS delay in the OVP along with the use of
>transorbs allows no battery operation while insuring a legitimate failure is
>detected and action taken . . .
Fine, show me the test data. I'm not saying that it cannot
be done but stories of demonstrations do not replace data
from demonstrations. By the same token, I'm not going to justify
the "over spec" stresses on a circuit breaker by telling you that
"I've done it thousands of times and have yet to kill a breaker."
The 5A field breaker in B&C's test stand was subject to many,
many ov test events for years before it ultimately needed replacing.
Before it died, it was still performing the intended function
to the extent that thousands of alternators and regulators
were run across that stand in their final acceptance tests. Far
more abuse than anything an airplane would do to it.
I'm talking to folks who manufacture breakers then I'll craft an
experiment to demonstrate what I believe to be true. Then I'll invite
anyone to critique that data so that anyone can be sure I'm not
trying to dry-lab an experiment to produce data that pushes an
agenda. The more I look into it, the more convinced I am of our
design decisions 25 years ago when we were qualifying the crowbar
system. Yes, it's rather indelicate but it satisfied numerous
design goals and bypassed problems common to ov relays at that
time.
> <SNIP>
> >
> > That was not the consideration at the the time. NOBODY but Barons
> > and Bonanzas allows battery-less operation by manipulation of
> > panel controls. There was a good reason for that long before the
> > manner and style of ov protection was considered. To imply that
> > I don't recommend battery-less operation just to satisfy some
> > feature of the ov protection system is a presumption of facts
> > not in evidence and patently untrue . . . I was there. I did it
> > and I know the foundation upon which the system was built.
>
>I know and certificated aircraft are not the issue here. I do not think they
>ever were given the ability to change the basic electrical design under the
>FAA regulations including batteries. Also what has been done in the past in
>not at issue. Past times the engine ran fine with no electrons needed.
>
>Today (and to for over 10 years) we have the need in some cases for large
>currents (10-20 amps) to keep the engine running. I object to the lack of
>the Aeroelectric connection not recognizing this and supporting this
>emerging use of electrically dependent engines There are thousands of auto
>conversions flying today and this is not new as the numbers have been
>growing over the last 15 years. This is nearly always a OBAM aircraft and
>yet today there is no electrical system design that meets that need
>properly.
Your objections are duly noted but totally mystifying. I've published
invitations for any and all creative persons to submit anything
they think should be a part of the 'Connection or the website with
only one small caveat . . . be prepared to defend it with a critical
design review.
The fact that I've not covered this information on my own is in
no way a reluctance to do so . . . there are only so many hours
in the day and it just hasn't moved to the front burners. When
you stated that you were going to do the testing and produce
a report on a system friendly to the automotive conversion
engines, I was delighted. But to date, the only thing I've
heard or seen is nit picking on what's wrong with stuff already
in place and nary a whit on what you want to put into Figure Z-21.
> <snip>
>
>Tested extensively and backed up with analysis. As you often say If you do
>not believe me do some analysis and post where I have gone wrong. I have
>both analysis and real tests to back up the analysis.
Be delighted to see it.
>However I have not studied the external regulator approach much as its
>easier to go with the flow as internal stock auto alternators are the wave
>of the future in OBAM. If I can get a brand new or quality rebuilt
>alternator for $200 to $300 why would I even consider the B & C nearly
>$1,000 approach. Even more important in the case of away from home failures
>the local auto store likely has a replacement in stock (an important
>consideration to many). There are at least 5000 OBAM acft flying with
>internal regulators and no OVP modules. Foolish perhaps but its hard to
>argue with the numbers. No known failure HI reported. Prop bolts anyone??
Really? Allow me to quote the following exchange from a few years
back at http://aeroelectric.com/articles/spike.pdf
On 4-2-98 he responds and I offer further comments .
. . .
Perhaps you missed the Kitfox alternator failure where
your regulator was installed and the later string of
failures that destroyed thousands of dollars of electronics
with a transient with a good battery installed. Clearly this
set of electronics needed better protection.
I believe you're referring to Peter G.'s experience
flying to Sun-n-Fun last year. Re-reading his post of
March 11th I've confirmed my recollection that he
started out with an LR3 regulator and a non-B&C
alternator suitably modified for compatibility with the
LR3.
An alternator failure en route prompted
replacement of the whole system with an alternator
having a built-in regulator and an OV protection
system that I'm not familiar with. No B&C hardware
was installed when the system smoked his radios.
If you're speaking about another airplane, I'm not
aware of it and would appreciate knowing who the
owner is.
------------------------------------------------
That's you and me talking. Yes, the failures are rare but
they're never pleasant. Peter isn't the only one to have
suffered the condition. If you have recommended alternator/
regulator combinations to recommend, lets include them
in the notes for Figure Z-21. I'm sure that you're not
suggesting that just any internally regulated alternator
will do.
I've published a first crack at Z-21 at:
http://www.aeroelectric.com/PPS/Architecture/Z21K.pdf
Let's mark it up and get the supporting notes crafted.
Here's not only an invitation but a plea to give us
the benefits of your ideas.
Bob . . .
Message 34
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--> AeroElectric-List message posted by: N1deltawhiskey@aol.com
In a message dated 04-Apr-05 11:09:27 Pacific Standard Time, jerry@mc.net
writes:
Confused in Illinois ...
Jerry Grimmonpre
Jerry,
As you are confused, Paul and his friend have successfully won.
If you were playing poker, would you rather bet on the outcome of a hand
where there was only 1 unknown rather that 5? With all the cards turned up, we
may not necessarily like the hand we have, but we can more safely bet on it than
if all the cards are down.
To be less confused, look a who is holding their cards face down vs. face up.
Doug Windhorn
Message 35
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| Subject: | Re: Cessna A-510 ignition switch |
--> AeroElectric-List message posted by: Dj Merrill <deej@thayer.dartmouth.edu>
Hi all,
Thought I'd post an update on my troubleshooting
in case anyone is interested. Turns out that after
disconnecting the mags from the back of the switch,
the keyswitch tests fine, so that is likely not
the problem.
The rest of this is decidedly non-electrical
in nature, and is probably somewhat off-topic, so please
stop reading if you are not interested... *grin*
I took the cowl off the Glasair and upon initial
inspection could not find anything obviously wrong.
So, throwing caution to the wind I decided to try
to start the engine again (the plane had been sitting
for about 2 weeks at this point since the engine had
died halfway down the runway while landing, throttle at idle).
The engine started right up like it always has, and ran fine.
No stutters, bumps, hiccups, and nothing sounded out of the ordinary.
I ran it up, and at various power settings for about 10 mins.
Hmmmm. I'm still looking for the smoking gun,
but I'm not even smelling the gun powder at this point.
So, let's review, says I. I landed on a rather rough
grass strip, and was bounced around a bit (but not
horribly so). Best I can come up with is:
1) carb ice (although I am fairly sure the carb heat was
on during the pattern descent, as normal).
2) vapor lock (although I am running 100LL, and it was
not a terribly hot day, maybe 50-55F, and I've never had
an instance of vapor lock in the three years I've been
flying it).
3) the bumpy landing bounced the float around in the
carb and caused it to stick, or some cruft in the
bottom of the carb was loosened up, causing the same.
4) The engine stalled for whatever reason being at
low idle, and something in the impulse coupling
stuck in the one mag, which would lot allow the
engine to be restarted (but I can't explain why
it worked 2 weeks later).
So I removed the drain from the bottom of the carb,
and drained the fuel out, and ran some more through it.
I could not find any debris in the fuel, but maybe
it got "sucked through" when I ran the engine.
Okay, put it back in, leak check by turning on the
electric fuel pump. Hey there, why do I have fuel
dripping out of the bottom of the carburator?
With the fuel boost pump on, I am reading about
6-6.5 lbs of fuel pressure, and fuel will drip rapidly
out of the air intake of the carb. I do not believe this
is normal - anyone care to comment? Is the pressure
high enough to force the float valve to open in the carb?
At the moment I am thinking that I have some carb
issues, although the engine seems to run fine now.
I can't seem to come up with any other explanation, though.
-Dj
--
Dj Merrill
deej@thayer.dartmouth.edu
"TSA: Totally Screwing Aviation"
Message 36
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| Subject: | Well Bob you win |
--> AeroElectric-List message posted by: "Chuck Jensen" <cjensen@dts9000.com>
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Paul
Messinger
Subject: AeroElectric-List: Well Bob you win
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
I cannot continue to spend the time when its clear we have such different
backgrounds and backgrounds of experience. There is simply no common ground
to a discussion.
In aerospace, "failure was not an option" so every design was subjected to a
detailed design review and the review package included a worst case design
analysis as well as a proof of concept, sample of one lab test. Design
approval was based on the worst case analysis demonstrating all component
variations resulted in parts stress of less that specified maximum so any
combination of parts would work and not be overstressed. Or even work as its
possible to have a single lab test work and production parts when assembled
fail to work. Happens more than some might think.
I have tried to reason and for a while I thought you were considering my
facts but that moment of sanity has past and you are back in the old mode
Bob is so famous for.
Just as one cannot test reliability in to a product:
You cannot test a bad design into a good one.
You cannot sample the population with one sample and get meaningful results
etc etc.
This is the only place where a single test is suffient to justify the design
is good.
I have never experienced a case where the designer not only had never done a
worst case analysis but clearly had no intention of doing so. This is based
on a partial worst case analysis I performed showing any part combination
would not work.
We have gotten into a debate and lately you have resorted to name calling to
the extent most of the list readers are confused and the original facts are
buried in reply's to reply's.
I have many more relevant things to bring up that potentially can effect how
OBAM aircraft are electrically wired but its clear that I am wasting my
time.
I have a real contract with a real player in the experimental engine market
to advance the state of the art. That is where I will be spending my time as
our debating is a huge waste of my time.
For those who may think I am an air head as Bob would like you to believe I
have enough commendations and awards for performance and technical
excellence to paper a hanger door and have paper left over.
How else would I win such a contract for a new generation of aircraft
electrical systems??
I have many posts that need reply's but they will simply not be posted this
is truly the end.
Any who want to ask me something must email directly to me.
Paul
Message 37
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| Subject: | Re: Cessna A-510 ignition switch |
--> AeroElectric-List message posted by: "Wayne Sweet" <w_sweet@comcast.net>
IMHO, the carb needs attention, such as a complete overhaul, just to be
thorough and complete. Why fuss around when a few $ will probably fix the
problem.
Wayne
----- Original Message -----
From: "Dj Merrill" <deej@thayer.dartmouth.edu>
Subject: Re: AeroElectric-List: Cessna A-510 ignition switch
> --> AeroElectric-List message posted by: Dj Merrill
> <deej@thayer.dartmouth.edu>
>
> Hi all,
> Thought I'd post an update on my troubleshooting
> in case anyone is interested. Turns out that after
> disconnecting the mags from the back of the switch,
> the keyswitch tests fine, so that is likely not
> the problem.
>
> The rest of this is decidedly non-electrical
> in nature, and is probably somewhat off-topic, so please
> stop reading if you are not interested... *grin*
>
> I took the cowl off the Glasair and upon initial
> inspection could not find anything obviously wrong.
> So, throwing caution to the wind I decided to try
> to start the engine again (the plane had been sitting
> for about 2 weeks at this point since the engine had
> died halfway down the runway while landing, throttle at idle).
> The engine started right up like it always has, and ran fine.
> No stutters, bumps, hiccups, and nothing sounded out of the ordinary.
> I ran it up, and at various power settings for about 10 mins.
>
> Hmmmm. I'm still looking for the smoking gun,
> but I'm not even smelling the gun powder at this point.
> So, let's review, says I. I landed on a rather rough
> grass strip, and was bounced around a bit (but not
> horribly so). Best I can come up with is:
>
> 1) carb ice (although I am fairly sure the carb heat was
> on during the pattern descent, as normal).
>
> 2) vapor lock (although I am running 100LL, and it was
> not a terribly hot day, maybe 50-55F, and I've never had
> an instance of vapor lock in the three years I've been
> flying it).
>
> 3) the bumpy landing bounced the float around in the
> carb and caused it to stick, or some cruft in the
> bottom of the carb was loosened up, causing the same.
>
> 4) The engine stalled for whatever reason being at
> low idle, and something in the impulse coupling
> stuck in the one mag, which would lot allow the
> engine to be restarted (but I can't explain why
> it worked 2 weeks later).
>
> So I removed the drain from the bottom of the carb,
> and drained the fuel out, and ran some more through it.
> I could not find any debris in the fuel, but maybe
> it got "sucked through" when I ran the engine.
> Okay, put it back in, leak check by turning on the
> electric fuel pump. Hey there, why do I have fuel
> dripping out of the bottom of the carburator?
>
> With the fuel boost pump on, I am reading about
> 6-6.5 lbs of fuel pressure, and fuel will drip rapidly
> out of the air intake of the carb. I do not believe this
> is normal - anyone care to comment? Is the pressure
> high enough to force the float valve to open in the carb?
>
> At the moment I am thinking that I have some carb
> issues, although the engine seems to run fine now.
> I can't seem to come up with any other explanation, though.
>
> -Dj
>
> --
> Dj Merrill
> deej@thayer.dartmouth.edu
>
> "TSA: Totally Screwing Aviation"
>
>
>
Message 38
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| Subject: | Re: Well Bob you win |
--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
This is an unfortunate conclusion of this part of the discussion. I
suspect that if
all of the players were in the same room together and had a couple of
calculators,
an internet connection and a dry erase board, all of this nonsense could
be sorted
out rather quickly. Start with a good breakfast.. Hungry people do not
think clearly. :)
The internet is a magical thing most of the time, but it is not a perfect
means of
communication. The interactivity is not perfect, and hence it will not
replace face to
face encounters.
Best regards,
Matt-
VE N34RD, C150 N714BK
> --> AeroElectric-List message posted by: "Paul Messinger"
> <paulm@olypen.com>
>
> I cannot continue to spend the time when its clear we have such
> different backgrounds and backgrounds of experience. There is simply no
> common ground to a discussion.
>
> In aerospace, "failure was not an option" so every design was subjected
> to a detailed design review and the review package included a worst
> case design analysis as well as a proof of concept, sample of one lab
> test. Design approval was based on the worst case analysis
> demonstrating all component variations resulted in parts stress of less
> that specified maximum so any combination of parts would work and not
> be overstressed. Or even work as its possible to have a single lab test
> work and production parts when assembled fail to work. Happens more
> than some might think.
>
snip
> Any who want to ask me something must email directly to me.
>
> Paul
>
>
Message 39
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--> AeroElectric-List message posted by: "Jerry Grimmonpre" <jerry@mc.net>
Hey Doug ...
Good point.
Along with that analogy, I would declare a misdeal and ask for a new deck of
cards ... the kind with all the Kings smiling!
Jerry Grimmonpre
> --> AeroElectric-List message posted by: N1deltawhiskey@aol.com
> Jerry,
>
> As you are confused, Paul and his friend have successfully won.
>
> If you were playing poker, would you rather bet on the outcome of a hand
> where there was only 1 unknown rather that 5? With all the cards turned
> up, we
> may not necessarily like the hand we have, but we can more safely bet on
> it than
> if all the cards are down.
>
> To be less confused, look a who is holding their cards face down vs. face
> up.
>
> Doug Windhorn
Message 40
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| Subject: | P-Mag Excess Amps response |
--> AeroElectric-List message posted by: "Joe & Jan Connell" <jconnell@rconnect.com>
This item forwarded to AeroElectric-List@matronics.com
Joe Connell
----- Original Message -----
From: Bob Barrow
Subject: PMag excess amps
Hi Joe, I've been reading the PMag thread with interest because I fancy the PMag
concept...but like everyone else I'm waiting for feedback from early users before
committing.
Anyway a recent post on the Aeroelectric list stated the following:
"From what I understand about the PMag.which I don't own, but may someday.
The generator puts out 12-14V at approx. 1500 RPM, and drops voltage output
as the RPM drops. The PMag & Emag will still make spark at some ridiculous
low number like 5 V. So by generating 5+ V at 800 RPM it is self
sustaining. The deal is - it has no excess voltage that can charge a
battery below 1500 RPM, but it can help in a failed alternator situation
above that RPM. Of course the output would be a very low amperage, and I
wouldn't count on continued flight after an alternator failure."
The above comment seems to imply that above 1500RPM the PMag can assist with battery
charging in the event of a failed alternator. The following is a comment
from Emagair which refutes the above :
Hello Bob:
1. The P-MAG power supply is designed to be as isolated as possible from the aircraft.
There is no provision for exporting excess current.
2. The P-MAG alternator is sized to match the needs of the ignition system. Yes,
the power output of the alternator does increase with rpm, but so does the
demand for spark energy. There is little surplus, regardless of engine speed.
I hope that helps.
Kindest Regards,
Brad Dement
I read Aerolectric posts but I cannot make a posting because I am not a subsciber
(don't want to be because it fills up my email box). So I thought you might
find the above information from Brad Dement interesting....and if so you might
like to post it to the Aeroelectric list because I'm sure others would also
find it interesting.
Regards Bob Barrow
RV7A Melbourne Australia
Message 41
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| Subject: | Re: Cessna A-510 ignition switch |
--> AeroElectric-List message posted by: Dj Merrill <deej@thayer.dartmouth.edu>
Wayne Sweet wrote:
> --> AeroElectric-List message posted by: "Wayne Sweet" <w_sweet@comcast.net>
>
> IMHO, the carb needs attention, such as a complete overhaul, just to be
> thorough and complete. Why fuss around when a few $ will probably fix the
> problem.
> Wayne
I agree - I just want to make sure that really
is the problem before shelling out another $400 bucks
to get the carb rebuilt, again (just had it done less than
2 years ago). I'm certainly not going to fly it before
I figure out the problem, but I also don't want to spend
money on something that does not need fixing (there's not
a lot of "spare" cash around these days). However, if the
carb does need attention, it will definitely get the full
attention it needs. It is my butt on the line, after all! :-)
Thanks,
-Dj
do not archive
--
Dj Merrill
deej@thayer.dartmouth.edu
"TSA: Totally Screwing Aviation"
Message 42
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| Subject: | Re: Well Bob you win |
--> AeroElectric-List message posted by: "n801bh@netzero.com" <n801bh@netzero.com>
In aerospace, "failure was not an option" so every design was
subjected to a
detailed design review and the review package included a worst case design
analysis as well as a proof of concept, sample of one lab test. Design
approval was based on the worst case analysis demonstrating all component
variations resulted in parts stress of less that specified maximum so any
combination of parts would work and not be overstressed. Or even work as its
possible to have a single lab test work and production parts when assembled
fail to work. Happens more than some might think
You don't happen to work at Lycoming in their "certified" crankshaft section do
ya???
They call themselves an aerospace company.....And so far their aerospace cranks
have killed at least 12 people in the last few years. So much for their overstressed
ideas.. The cranks probably looked good on "paper"
Ben Haas
N801BH
www.haaspowerair.com
Message 43
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| Subject: | Zeftronics transistor |
--> AeroElectric-List message posted by: "Brian Kraut" <brian.kraut@engalt.com>
This one supposedly has protection against shorts on the field wire, oh
well. I guess an intermittent short for a long time was just a little too
much.
I did call today and ask for tech support and got someone with an accent. I
guess that was Femmi. He gave me a flat out "no" when I asked for the part
number. Nothing really secret about it since the number was on the part
before it burned up. Guess it is a liability thing.
I can figure out something that will work fine easily enough, it just sure
would be nice if someone had the correct part number though.
Brian Kraut
Engineering Alternatives, Inc.
www.engalt.com
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Robert
L. Nuckolls, III
Subject: Re: AeroElectric-List: Zeftronics transistor
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<b.nuckolls@cox.net>
At 07:05 PM 4/3/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: "Brian Kraut"
><brian.kraut@engalt.com>
>
>I have a Zeftronics R15100 voltage regulator that is blown because the
>previous owner of the plane used a shielded wire on the alternator without
>the shield insulated and it shorted to the field stud on the alternator.
Yup . . . field shorts will take down many regulator designs . . . A
B&C LR-3 uses the crowbar system to shut down the supply and protect the
regulator in case of a field short.
>The TO-220 output transistor is toasted and I can't read the complete part
>number on it. It is a TIP1 something. If I had to take a wild ass guess I
>would say a TIP120 is the most likely candidate, but I want to be sure.
>Does anyone know for sure or know where I can get a schematic?
You might call Zeftronics and ask . . . as for Femmi (assming
he's still there). He might just tell you the part number.
It's a plain vanilla transistor. Get someting good for 5A or more,
80v or more. Try a PNP and operate if from a variable power supply
on the bench using a 10 ohm resistor for a "field" load. 99% sure
this will fix it. I've not seen a practical approach to using an
NPN transistor in that slot on a regulator.
Bob . . .
Message 44
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| Subject: | Re: Looking for a B&C oil pressure switch pinout... |
--> AeroElectric-List message posted by: "Werner Schneider" <glastar@gmx.net>
Bob,
it's in your seminar drawings sheet #20 =(;o)
S = common lead
P = should be open contact (no oil pressure)
I = closed contact (no oil pressure)
I had one of this switches failing and got a replacement with the
Common: COM
Normally Open: NO
Normally Closed: NC
markings, there should be a drwaing included with the switch.
Werner
----- Original Message -----
From: "Robert L. Nuckolls, III pinout..." <b.nuckolls@cox.net>
Subject: Re: AeroElectric-List: Looking for a B&C oil pressure switch
pinout...
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<b.nuckolls@cox.net> pinout...
>
> At 11:29 AM 4/3/2005 -0700, you wrote:
>
> >--> AeroElectric-List message posted by: "Marcos Della"
<mdella@cstone.com>
> >
> >
> >Ok, I got one of the three connector switches. Normally I've seen the
> >connections
> >Marked as C, NC, and NO. On this one they are marked P, S, and I... So.
> >Which ones
> >Are which? w/o pressure, P and S are shorted... But I don't know which
> >one of them
> >Is the "common" lead...
>
> I used to sell that switch and thought I had the data on it but
> can't put my hands on it. Call Tim at B&C.
>
> Bob . . .
>
>
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