Today's Message Index:
----------------------
1. 03:55 AM - Fw: LVWM and Kilovac contactors (Gilles Thesee)
2. 05:14 AM - Re: 1N4004 vs 1N4001 (Brian Lloyd)
3. 05:50 AM - Re: 1N4004 vs 1N4001 (Mickey Coggins)
4. 06:01 AM - Re: Fw: LVWM and Kilovac contactors (Paul Pengilly)
5. 06:37 AM - Re: 1N4004 vs 1N4001 (Brian Lloyd)
6. 06:43 AM - Re: Trim Systems (Robert L. Nuckolls, III)
7. 06:48 AM - Re: Fw: LVWM and Kilovac contactors (Robert L. Nuckolls, III)
8. 06:48 AM - Re: Fw: LVWM and Kilovac contactors (Gilles Thesee)
9. 06:58 AM - Re: Fw: LVWM and Kilovac contactors (Robert L. Nuckolls, III)
10. 07:07 AM - Re: Conduit Ground System (Robert L. Nuckolls, III)
11. 07:15 AM - Re: Trim Relay Deck (Robert L. Nuckolls, III)
12. 07:28 AM - Re: Fw: LVWM and Kilovac contactors (Gilles Thesee)
13. 07:52 AM - Re: 1N4004 vs 1N4001 (Robert L. Nuckolls, III)
14. 07:55 AM - Re: Fw: LVWM and Kilovac contactors (Paul Messinger)
15. 08:26 AM - Starter Contactor (Maureen & Bob Christensen)
16. 08:56 AM - Re: Fw: LVWM and Kilovac contactors (Gilles Thesee)
17. 09:47 AM - Re: Schematic Review ()
18. 01:36 PM - Re: whalen strobe wire size (Bill and Marsha)
19. 02:05 PM - Re: Starter Contactor (Robert L. Nuckolls, III)
20. 02:17 PM - Re: Re: Schematic Review (Ken Harrill)
21. 03:14 PM - Re: Re: whalen strobe wire size (Joel Jacobs)
22. 05:54 PM - Re: Re: Starter Contactor (Maureen & Bob Christensen)
23. 06:06 PM - Re: Re: Starter Contactor (Robert L. Nuckolls, III)
24. 06:48 PM - Re: Re: Starter Contactor (Scott Jackson)
25. 08:10 PM - OV and Vans 60amp Alternator was 55 Amp Suzuki Alternator (Bobby Hester)
26. 08:24 PM - Re: Starter Contactor (Robert L. Nuckolls, III)
27. 10:57 PM - Re: Re: Starter Contactor (Scott Jackson)
Message 1
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| Subject: | LVWM and Kilovac contactors |
--> AeroElectric-List message posted by: "Gilles Thesee" <Gilles.Thesee@ac-grenoble.fr>
Hi Bob and all,
Hope you won't mind my reposting my last question.
As stated below I made some progress in understanding where the snag might
come from. But I'm still wondering what the problem could be and how I could
possibly work around it.
Any idea as to where to investigate ?
I can send again the diagrams.
Season's greetings,
Gilles Thesee
===========================================================
----- Original Message -----
From: "Gilles Thesee" <Gilles.Thesee@ac-grenoble.fr>
Subject: AeroElectric-List: LVWM and Kilovac contactors
> --> AeroElectric-List message posted by: "Gilles Thesee"
<Gilles.Thesee@ac-grenoble.fr>
>
> Bob,
>
> Some time ago I asked questions about problems with my low voltage
warning.
>
> My diagram is as per figure Z16 with two batteries and ABMM.
> The main battery is monitored by the ABMM, and the auxiliary battery
voltage
> is monitored by a Low Voltage Warning Module with switching functionality
to
> light a panel light when the Aux battery is not online.
> To prevent the LVWM from draining the Aux battery, it is powered through a
> small relay energized by the E-bus.
> I hope my description is clear enough.
>
> Now here is my problem :
> When the ship is powered by a bench supply via the 'cold' contact of the
> main battery contactor, everyhing works as expected.
> But when the Kilovac EV 200 main contactor is energized, the LVWM fails to
> annunciate.
>
> To make a long story short, I came to the conclusion the relay was the
> culprit. When the Kilovac contactor comes on line, the small relay opens,
> isolating the LVWM.
> I conducted some tests with another relay with the same result. I borrowed
a
> standard Cutler-Hammer contactor and used it with jumpers in the airplane
:
> no problem with the LVWM.
> The Kilovac has a special economizer circuit, but how can it disturb this
> particular relay, and only this one ? After all a contactor is a
contactor,
> and everything else is working.
>
> Have you heard about such a problem with the Kilovac EV 200 contactors, or
> do you have an idea as to how to work around the problem ?
>
> Thanks for your help,
> Regards,
>
> Gilles
========================================================
Message 2
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| Subject: | Re: 1N4004 vs 1N4001 |
--> AeroElectric-List message posted by: Brian Lloyd <brianl@lloyd.com>
On Dec 18, 2004, at 3:14 PM, Mickey Coggins wrote:
> --> AeroElectric-List message posted by: Mickey Coggins
> <mick-matronics@rv8.ch>
>
> Hi,
>
> I'm trying to figure out if in our 14v systems there would ever be a
> reason to use an 1N4004 diode vs. a 1N4001 diode. According to the
> data
> sheets I've read, the only difference seems to be Vmax is 50V for the
> 1N4001 and 400V for the 1N4004. Are there any other differences or
> advantages/disadvantages of one over the other?
No.
> The application is to
> keep current from flowing the wrong way on a panel LED indicator.
Well, you might not need the diode then. The LED is also a diode and
will not conduct or light up with reverse voltage applied. I suspect
that you will find that the peak inverse voltage for an LED is on the
order of 50V. In that case the LED is its own 'protection' diode. You
don't need another diode in series.
And even if it does break down in the reverse current direction
(unlikely), the series current-limiting resistor will limit the reverse
current to a safe value thus preventing damage to the device.
OTOH, if the diode is a two-color device where reverse current flow
lights the LED of the alternate color you might need steering diodes to
prevent reverse current from lighting the other diode.
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
+1.340.998.9447 St. Thomas, VI 00802
I fly because it releases my mind from the tyranny of petty things . . .
Antoine de Saint-Exupry
Message 3
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| Subject: | Re: 1N4004 vs 1N4001 |
--> AeroElectric-List message posted by: Mickey Coggins <mick-matronics@rv8.ch>
>>sheets I've read, the only difference seems to be Vmax is 50V for the
>>1N4001 and 400V for the 1N4004. Are there any other differences or
>>advantages/disadvantages of one over the other?
>
>
> No.
Thanks.
>>The application is to
>>keep current from flowing the wrong way on a panel LED indicator.
>
>
> Well, you might not need the diode then. The LED is also a diode and
> will not conduct or light up with reverse voltage applied. I suspect
> that you will find that the peak inverse voltage for an LED is on the
> order of 50V. In that case the LED is its own 'protection' diode. You
> don't need another diode in series.
I didn't know this - thanks for the info. The original design, which
was done by someone else, was for an incandescent bulb. This is
probably why they recommended a diode. I decided that a LED would
be "cooler".
I'm planning on being at SNF, and I really hope I can buy all
you guys beers that have helped me out so much over these last
few months.
Thanks again, and best regards.
Mickey
--
Mickey Coggins
http://www.rv8.ch/
#82007 Wiring
Message 4
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| Subject: | Re: LVWM and Kilovac contactors |
--> AeroElectric-List message posted by: Paul Pengilly <pengilly@southwest.com.au>
Your problem lies with your statement !! and I have seen this problem
before
your statement a contactor is a contactor is not correct a electronic
contactor
can cause problems with circuits and when these problems arise you are
better off
throwing them and using the standard design, that way when you breakdown
and need
a part you can get it.
Regards
Paul
do not archive
>--> AeroElectric-List message posted by: "Gilles Thesee" <Gilles.Thesee@ac-grenoble.fr>
>
>Hi Bob and all,
>
>Hope you won't mind my reposting my last question.
>As stated below I made some progress in understanding where the snag might
>come from. But I'm still wondering what the problem could be and how I could
>possibly work around it.
>Any idea as to where to investigate ?
>I can send again the diagrams.
>
>Season's greetings,
>
>Gilles Thesee
>
>===========================================================
>----- Original Message -----
>From: "Gilles Thesee" <Gilles.Thesee@ac-grenoble.fr>
>To: <aeroelectric-list@matronics.com>
>Subject: AeroElectric-List: LVWM and Kilovac contactors
>
>
>
>
>>--> AeroElectric-List message posted by: "Gilles Thesee"
>>
>>
><Gilles.Thesee@ac-grenoble.fr>
>
>
>>Bob,
>>
>>Some time ago I asked questions about problems with my low voltage
>>
>>
>warning.
>
>
>>My diagram is as per figure Z16 with two batteries and ABMM.
>>The main battery is monitored by the ABMM, and the auxiliary battery
>>
>>
>voltage
>
>
>>is monitored by a Low Voltage Warning Module with switching functionality
>>
>>
>to
>
>
>>light a panel light when the Aux battery is not online.
>>To prevent the LVWM from draining the Aux battery, it is powered through a
>>small relay energized by the E-bus.
>>I hope my description is clear enough.
>>
>>Now here is my problem :
>>When the ship is powered by a bench supply via the 'cold' contact of the
>>main battery contactor, everyhing works as expected.
>>But when the Kilovac EV 200 main contactor is energized, the LVWM fails to
>>annunciate.
>>
>>To make a long story short, I came to the conclusion the relay was the
>>culprit. When the Kilovac contactor comes on line, the small relay opens,
>>isolating the LVWM.
>>I conducted some tests with another relay with the same result. I borrowed
>>
>>
>a
>
>
>>standard Cutler-Hammer contactor and used it with jumpers in the airplane
>>
>>
>:
>
>
>>no problem with the LVWM.
>>The Kilovac has a special economizer circuit, but how can it disturb this
>>particular relay, and only this one ? After all a contactor is a
>>
>>
>contactor,
>
>
>>and everything else is working.
>>
>>Have you heard about such a problem with the Kilovac EV 200 contactors, or
>>do you have an idea as to how to work around the problem ?
>>
>>Thanks for your help,
>>Regards,
>>
>>Gilles
>>
>>
>========================================================
>
>
>
>
Message 5
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| Subject: | Re: 1N4004 vs 1N4001 |
--> AeroElectric-List message posted by: Brian Lloyd <brianl@lloyd.com>
> --> AeroElectric-List message posted by: Mickey Coggins
> <mick-matronics@rv8.ch>
>
>>> sheets I've read, the only difference seems to be Vmax is 50V for the
>>> 1N4001 and 400V for the 1N4004. Are there any other differences or
>>> advantages/disadvantages of one over the other?
>>
>>
>> No.
>
> Thanks.
You are welcome.
>>> The application is to
>>> keep current from flowing the wrong way on a panel LED indicator.
>>
>> Well, you might not need the diode then. The LED is also a diode and
>> will not conduct or light up with reverse voltage applied. I suspect
>> that you will find that the peak inverse voltage for an LED is on the
>> order of 50V. In that case the LED is its own 'protection' diode.
>> You
>> don't need another diode in series.
>
> I didn't know this - thanks for the info. The original design, which
> was done by someone else, was for an incandescent bulb. This is
> probably why they recommended a diode. I decided that a LED would
> be "cooler".
I suspected as much. No, you don't need a blocking diode with an LED.
OTOH, you might need a resistor across the LED to keep leakage current
from causing the LED to glow dimly even if it is supposed to be turned
off.
> I'm planning on being at SNF, and I really hope I can buy all
> you guys beers that have helped me out so much over these last
> few months.
It would be nice to go to SnF but I am not going to hold my breath I
will make it. Anyway, consider me thanked. I wish you the best of
luck on the happy completion of your project.
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
+1.340.998.9447 St. Thomas, VI 00802
There is a time to laud one's country and a time to protest. A good
citizen is prepared to do either as the need arises.
Message 6
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| Subject: | Re: Trim Systems |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 07:04 AM 12/17/2004 +0000, you wrote:
>Below is the result of your inquiry. It was submitted by
>Roee Kalinsky (roee@kalinskyconsulting.com) on Thursday, December 16, 2004
>at 23:04:05
>
>Thursday, December 16, 2004
>
>Roee Kalinsky
>
>,
>Email: roee@kalinskyconsulting.com
>Comments/Questions: Bob, thanks for publishing the aeroelectric
>connection. It's a great resource.
>
>I'm contemplating building my own control circuits for MAC servos in an
>RV-7A. I looked at your schematics for a "roll your own" relay deck, and
>had a couple of questions:
>
>1. Seems to me you'd want to use diodes or another form of protection for
>the relay contacts against the inductive kick from the servo motor. Is
>there a reason I'm not aware of why this is not necessary?
The actuator motor doesn't have any "kick" . . . the relay coils
do. If they're small relays, there's little risk and not much
value in adding spike suppression . . . but it doesn't hurt if
you'd like to do it.
>2. Have you tried using FETs instead of relays for this application? If
>so I'd like to hear about your experience. If not, why not?
Sure . . . all new designs are solid state. 98% of the folks I
write for have rudimentary assembly skills. The S704-1 relay with
it's built in mounting base, fast-on tabs, and totally enclosed
design is attractive for it's ease of implementation.
>3. Do you know if a PWM would be a good approach for speed control on
>these servo motors?
Ether PWM or a rigid regulator would suffice. I prefer the
rigid voltage regulator. PWM without a speed feedback sensing
system (closed loop servo) is more like using a series resistor
to control speed. The goal is to be as stable as possible for
all variations including load on motor and bus voltage variations.
The LM317 series voltage regulators do a good job of filtering
out bus voltage changes.
>For reference, I'm an EE but I deal mostly with microelectronics. I admit
>I have near zero experience with motor control. Thanks for your help
Understand. Have you seen the collection of drawings
at http://www.aeroelectric.com/PPS/Flight/Trim
One of those drawings at:
http://www.aeroelectric.com/PPS/Flight/Trim/trim6.pdf
illustrates the linear regulator speed control for
the PM motor actuator.
I will invite you to join us on the AeroElectric List
to continue this and similar discussions. It's useful to
share the information with as many folks as possible.
A further benefit can be realized with membership on
the list. There are lots of technically capable folks
on the list who can offer suggestions too. You can
join at . . .
http://www.matronics.com/subscribe/
Thanks!
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
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Message 7
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| Subject: | Re: LVWM and Kilovac contactors |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 12:13 PM 12/20/2004 +0100, you wrote:
>--> AeroElectric-List message posted by: "Gilles Thesee"
><Gilles.Thesee@ac-grenoble.fr>
>
>Hi Bob and all,
>
>Hope you won't mind my reposting my last question.
>As stated below I made some progress in understanding where the snag might
>come from. But I'm still wondering what the problem could be and how I could
>possibly work around it.
>Any idea as to where to investigate ?
>I can send again the diagrams.
>
>Season's greetings,
>
>Gilles Thesee
Sorry my friend, I thought I'd read where you ran this dog
to ground. I'm mystified by your experience. I'm wondering
what the Kilovac contactor uses in the way of electronics
for holding current reduction and if that feature has
some noise that interacts with the LVM/ABMM modules.
Just for grins, can you put your hands on one of those
el-cheepo contactors. Substituting a plain-vanilla contactor
for the Kilovac product would, by process of elimination,
point us in the right direction.
Bob . . .
--
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Message 8
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| Subject: | Re: LVWM and Kilovac contactors |
--> AeroElectric-List message posted by: "Gilles Thesee" <Gilles.Thesee@ac-grenoble.fr>
> Your problem lies with your statement !! and I have seen this problem
> before
> your statement a contactor is a contactor is not correct a electronic
> contactor
> can cause problems with circuits and when these problems arise you are
> better off
> throwing them and using the standard design, that way when you breakdown
> and need
> a part you can get it.
Paul,
Thanks for your message.
Of course I would like to get some additionnal info before throwing brand
new contactors away ! The rest of the ship's system work as expected. The
power section of the EV 200 is just like any other contactor, so my question
is, what can pose a problem with the bus when it is powered through them ?
Can you be a bit more specific as to what problem you have encountered ?
Regards,
Gilles
Message 9
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| Subject: | Re: LVWM and Kilovac contactors |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 10:02 PM 12/20/2004 +0800, you wrote:
>--> AeroElectric-List message posted by: Paul Pengilly
><pengilly@southwest.com.au>
>
>Your problem lies with your statement !! and I have seen this problem
>before
>your statement a contactor is a contactor is not correct a electronic
>contactor
>can cause problems with circuits and when these problems arise you are
>better off
>throwing them and using the standard design, that way when you breakdown
>and need
>a part you can get it.
>Regards
>Paul
This may be true but allow me to suggest that it's far
better to know all of the simple-ideas underlying ALL
of our choices for components. In the certified side of
general aviation, we have far too many antiques going out
the door in brand new airplanes because the cost-of-education
has been judged "too high".
If there is any single feature lacking in the engineering
of modern aircraft it's the loss of our "skunk works" facilities.
Today's management would like to believe that we can
take piles of catalogs (on the Internet of course) and
sit at a CAD 'scope and design a pristine product.
The concept of a flight test hangar where engineers
and good technicians have the freedom to fail inexpensively
has been replaced with some utopian notions of
design by "Integrated Product Development Systems" . . .
Creativity is not a process but an art that depends on
the science of understanding. It works best
when everyone involved is getting their hands dirty
and everyone contributes from their personal bag of
simple-ideas (education acquired to date).
Bob . . .
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Message 10
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| Subject: | Re: Conduit Ground System |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 11:14 AM 11/19/2004 +0000, you wrote:
>--> AeroElectric-List message posted by: Graham Singleton
><graham@gflight.f9.co.uk>
>
>At 23:55 16/12/2004 -0800, you wrote:
> >Canard Pusher Grounding Scheme
> >
> >--> AeroElectric-List message posted by: "Eric M. Jones"
> <emjones@charter.net>
> >
> >I have a vested interest in this---but if it were my airplane I would look
> >at the Super-2-CCA FatWire.
> >
> >Regards,
> >Eric M. Jones
>
>
>So would I, but I'd also look at using a soft aluminum tube for the ground.
>Might be a bit tricky though and certainly more work.
>Does anyone make copper coated aluminum tube?
>Graham
If you analyze this option for total parts count, difficulty of
fabricating and maintaining low resistance joints and labor to
install, you may find that it's not very good value. I suggested
the copper conduit design in the first issues of the 'Connection
because it was a close clone of a system I did in a Long Ez about
1983 which was being converted to a UAV. We needed a super quiet
electrical system . . . especially in the area of the back seat
where the avionics sits. The airplane's front seat was still
usable for manned-flight operations.
The conduit was also attractive to the skunk works environment
where we were adding and removing wires running the length of
the airplane.
After several years of discussions with builders who installed
the copper tube conduit, we deduced that this was overkill for
an OBAM aircraft and a pair of fat wires tied together for
parallel-conductor field-cancellation was quite adequate to
the mission.
I presume you're interested in getting your project airborne
with the minimum of time and effort while crafting on-board
systems with high levels of performance. I can confidently
suggest now that conduit ground systems have a poor return
on investment of time for the benefits to be realized.
Bob . . .
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Message 11
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| Subject: | Re: Trim Relay Deck |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 05:30 PM 12/18/2004 -0500, you wrote:
>--> AeroElectric-List message posted by: SportAV8R@aol.com
>
>Thank you, Bob, for everything you do to help the OBAM community
>along. I'm indebted to you, because as I refine and re-do my RV's
>electrics, I am increasingly the beneficiary of your mental sweat.
It's "sweat" only when it's hard . . . you folks are responsible
for much of my success as a designer and troubleshooter at
Raytheon. I've learned more about fabricating elegant systems
on the List than I have in my professional activities at
RAC. We are better able to sift the sand here for simple-ideas
in the skunk-works that is the collection of your workshops
classroom that is the collection of your past experiences.
This is a symbiotic relationship from which we all benefit
so my thanks go out to you to sir.
Bob . . .
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Message 12
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| Subject: | Re: LVWM and Kilovac contactors |
--> AeroElectric-List message posted by: "Gilles Thesee" <Gilles.Thesee@ac-grenoble.fr>
Bob,
Thank you for responding.
I'm mystified by your experience. I'm wondering
> what the Kilovac contactor uses in the way of electronics
> for holding current reduction and if that feature has
> some noise that interacts with the LVM/ABMM modules.
>
In fact I believe I traced the problem down to the small relay that powers
the LVWM. I removed the LVWM fuse and the problem still seemed to be with
the relay. I made the same test with a different relay : same problem.
> Just for grins, can you put your hands on one of those
> el-cheepo contactors. Substituting a plain-vanilla contactor
> for the Kilovac product would, by process of elimination,
> point us in the right direction.
This is what I did : I removed a standard contactor from an aerobatic
airplane and tested it with jumpers : no more problems, the small relay and
the LVWM operate as intended.
What mystifies me is that the contactor powers the e-bus, and the relay
should not care who's bringing power to the bus. I thought about the noise
issue, but how come this noise disturbs only the relay in question ?
I'm intending to conduct any investigation needed to sort out the problem.
Would it help to wire a diode between the plus contact and the relay coil
lead ?
Thanks ,
Gilles
Message 13
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| Subject: | Re: 1N4004 vs 1N4001 |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 08:22 AM 12/20/2004 +0100, you wrote:
>--> AeroElectric-List message posted by: Mickey Coggins
><mick-matronics@rv8.ch>
>
> > As the peak inverse voltage rating goes up with each different P/N, the
> > forward voltage (conducting) voltage drop also goes up.
> > Bob White
>
>That was my concern, but I could not find any indication of this on
>the data sheet. Did you see something else that led you to this
>conclusion?
Hmmm . . . this may be true in practice but I suspect the
effect is very small. So small in fact that the data
sheets don't talk about it.
http://www.fairchildsemi.com/ds/1N/1N4007.pdf
Bob . . .
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Message 14
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| Subject: | Re: LVWM and Kilovac contactors |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
I have decided that the best contactor around for many reasons is the
Kilovac. The coil circuit is nothing strange just remember you are really
powering up electronics not a inductive coil.
I do not remember your exact circuit but I have extensively used these
contactors and can find no down side other than price.
The contact part of the kilovac is isolated from the "coil" circuit and acts
just like any other contactor with a couple of differences. It has little or
no contact bounce and the release time is much shorter. So its quicker and
much less likely to have contact bounce. My seemingly never ending test
report shows extensive fallout from the auto style contactors with both the
hold time from the diode and also the occasional huge contact bounce that
had secondary effects under sone specific ciruit setup conditions.
Can you remind us of your original circuit and problems.
Paul
----- Original Message -----
From: "Gilles Thesee" <Gilles.Thesee@ac-grenoble.fr>
Subject: Re: Fw: AeroElectric-List: LVWM and Kilovac contactors
> --> AeroElectric-List message posted by: "Gilles Thesee"
<Gilles.Thesee@ac-grenoble.fr>
>
>
> > Your problem lies with your statement !! and I have seen this problem
> > before
> > your statement a contactor is a contactor is not correct a electronic
> > contactor
> > can cause problems with circuits and when these problems arise you are
> > better off
> > throwing them and using the standard design, that way when you breakdown
> > and need
> > a part you can get it.
>
>
> Paul,
>
> Thanks for your message.
> Of course I would like to get some additionnal info before throwing brand
> new contactors away ! The rest of the ship's system work as expected. The
> power section of the EV 200 is just like any other contactor, so my
question
> is, what can pose a problem with the bus when it is powered through them ?
> Can you be a bit more specific as to what problem you have encountered ?
>
> Regards,
>
> Gilles
>
>
Message 15
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| Subject: | Starter Contactor |
--> AeroElectric-List message posted by: "Maureen & Bob Christensen" <mchriste@danvilletelco.net>
This may be a stupid question . . .
Is there a up or down to a (Van's) starter contactor . . . mine comes closer
than I like to the engine mount (RV-8) when it's mounted with the terminals
down . . . I talked a another builder who had mounted his that way
(terminals down) and he had heard G forces (causing the starter to run)
during aerobatics may be a factor when it's mounted terminal up.
Is the a problem with mounting the contactor terminals up?
Thanks,
Bob
Message 16
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| Subject: | Re: LVWM and Kilovac contactors |
--> AeroElectric-List message posted by: "Gilles Thesee" <Gilles.Thesee@ac-grenoble.fr>
> I have decided that the best contactor around for many reasons is the
> Kilovac. The coil circuit is nothing strange just remember you are really
> powering up electronics not a inductive coil.
>
> I do not remember your exact circuit but I have extensively used these
> contactors and can find no down side other than price.
>
> The contact part of the kilovac is isolated from the "coil" circuit and
acts
> just like any other contactor with a couple of differences. It has little
or
> no contact bounce and the release time is much shorter. So its quicker and
> much less likely to have contact bounce. My seemingly never ending test
> report shows extensive fallout from the auto style contactors with both
the
> hold time from the diode and also the occasional huge contact bounce that
> had secondary effects under sone specific ciruit setup conditions.
>
> Can you remind us of your original circuit and problems.
>
> Paul
Paul,
Thank you for you reassuring message. You'll find the circuits in question
at the following URL.
http://gilles.thesee.free.fr/TOTO.pdf
The general architecture diagram is not up to date (aux battery management
switch, LVWM relay wiring). But the individual circuit diagrams are.
When I have time to spare (when the airplane is ready and free of bugs ;-),
I'll upgrade my website.
Your help is much appreciated !
Regards,
Gilles
Message 17
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| Subject: | RE: Schematic Review |
--> AeroElectric-List message posted by: <swmat@cox.net>
Bob,
Thank you for your response. I am familiar with the FEMA concept but
exercising these principles will be a new path to me. If you are willing
to help me through it, I'll be happy to participate, I understand your
concept and the goal of the exercise.
To answer your first question: The mission for the aicraft is long range
IFR flight will dual electronic ignition, EFIS glass cockpit, with
electrical backups and static backups, no vacuum system is planned.
As previously stated, the goals are simple operation and sufficient
redundancy to provide comfortable flight into known IFR conditions.
Secondary goals are light weight aft of the firewall and low cost.
I chose Z-13 as a foundation because it provides dual power sources, and
utilizes the SD-8 alternator which is a light weight (and low cost) unit
which helps to address weight goal aft of the firewall. I also like the
SD-8 design which as a PM alternator is very simple with few moving
parts.
I have found Z-13 to be sufficient for the intended mission and goals of
this aircraft in all areas. My main motivation for wanting two batteries
is the maintenance aspect of it. I can simply replace one of the
batteries on a yearly basis, rotating them around as you describe. On
the long-ez I have a requirement of a certain amount of nose weight that
is intended to be battery. Knowing that I'll need about 25-30 pounds of
batteries to satisfy my W&B, I found the Z-30 diagram and endeavored to
add it to Z-13.
After adding Z-30, I realized that I now had a circuit which offers a
new failure mode protection. A rare occurance of battery failure could
now be considered a 'no sweat' situation. If one of the batteries fails,
it can be isolated and the main bus can be powered by the remaining good
battery. Another failure mode which is now easily accomodated is 'master
switch' failure or even a battery contactor failure. If either of these
itesm fail, the main bus can be powered by the aux battery.
At this point in my integration of Z-30 I had to make a couple of
choices. First, how does the essential bus alternate feed integrate with
the dual battery configuration? My decision was to change the alternate
feed SPST switch to a SPDT switch. This allows essential bus to be fed
from either battery.
This presents a new problem with Z-30 integration into the Z-13
schematic. The SD-8 output is wired to the battery bus in Z-13. After
adding Z-30 there are two battery busses. I chose to again change the
Ebus feed switch. It now becomes a 2-1 switch, switching both the SD-8
and the alt feed. The resulting schematic is Z-13 with a full
integration of Z-30.
I searched the archives on battery failure, and it is obvious that it is
a very rare event and the odds are that it won't ever happen. I accept
that this may be a failure mode that is not worth considering, however
as you have pointed out in the past having dual batteries offers
advantages in maintenance of the system.
The following link discusses failure modes of RG batteries:
http://www.dynastybattery.com/cd_dyn/contact/tech_support/7264.htm
Here is my attempt at an analysis of an in-flight battery failure (Cell
short) in a Z-13 configuration:
If a single cell shorts, the charging current from the primary
alternator will increase. The internal resistance of the battery will
decrease, and the voltage on the remaining good cells will increase. The
bus voltage should remain the same, the remaining good cells will begin
to be over-charged and the battery temperature will begin to rise.
Method of detection: Unusually high charging current
Detection of failure during pre-flight: If we pre-suppose that a cell
short is possible in flight, it could not be detected in a pre-flight
configuration. An existing cell short could be detected during
pre-flight by the noticeably lower terminal voltage and poor cranking
performance and more likely inability to start the engine.
Is the failure a hazard to flight? This failure would over-charge the
battery, possibly causing the 'venting' of the battery due to this
overcharge condition, battery overheating and could potentially cause
the alternator fuse to blow. Another possible harmful effect is of the
short causing an internal arc that could cause battery explosion. (see
the dynasty article).
Will this failure overtax piloting skills and be deterimental to the
comfortable termination of the flight? The observance of this failure
mode would indicate to the pilot the need to turn off the Z-13 master
switch. This would disconnect the alternator from the failed battery.
The bus voltage would be low and of an unknown remaining capacity.
Engagement of the Aux alternator would not be recommended, as this would
begin to over-charge the battery in the same manner as the main
alternator, further aggravating the situation. The only alternative is
to remain on battery only power with no certainty of sufficient power
reserves to successfully terminate the flight.
The second failure mode is simpler, an 'open' cell. This failure would
cause the alternator voltage to rise as the battery circuit would no
longer be complete. The overvoltage protection would disconnect the
alternator from the circuit and the main bus would go dark. The SD-8
alternator cannot be utilized without a battery (I searched the
archives, msg #11464). In the event of a battery 'open' failure the
panel would remain dark even with two alternators aboard. The dual
electronic ignition systems would be dead as well. This failure mode
would be immediately apparent, and would pose substantial risk to the
succesful completion of the flight.
Is this the type of dialog you were hoping for?
I realize that battery failures of this type are a very rare occurance
with properly maintained batteries. However, I have experienced a
shorted cell in my previous automobile with a sealed lead acid battery
that resulted in a battery explosion. Thankfully the battery was under
the hood, not in the cabin with me. I do not know if this was an AGM
battery, it was a 'maintenance free' battery as sold by a major auto
parts chain.
All of my experiences with 'maintenance free' batteries in automobiles
have been poor. My current vehicle came with a Yuasa 'maintenance free'
battery. It was small and cranked the engine well. It was replaced twice
by the dealer under factory warranty due to failure (internally shorted
cell) within a period of two years. When the third 'maintenance free'
battery failed six months later in the same manner I replaced it with an
Interstate brand flooded battery. The cranking performance is not as
good, and of course I have to periodically maintain the water level but
it has not shorted or otherwise failed. I assume that these batteries
are of an Recombinant Gas design if they are sealed. I do not know if
they were AGM batteries or not. I do not know the cause of the poor
performance of 'maintenance free' batteries.
If you look at a comparison of a dual alternator single battery system
with a dual battery, single alternator system, it appears to me that the
dual battery system appears to be a more robust system.
With the dual battery, single alternator system, if the alternator
fails, the two good batteries continue to provide power. If one the
batteries fail, the remaining good battery and the alternator continue
to provide power. This design can tolerate several modes of
wiring/contactor/switch failure.
The single battery dual alternator system cannot tolerate a battery
failure because of the reliance on the battery for alternator output.
This design cannot tolerate a battery wiring failure.
--Scott
San Diego, CA
Message 18
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| Subject: | Re: whalen strobe wire size |
--> AeroElectric-List message posted by: "Bill and Marsha" <docyukon@ptcnet.net>
----- Original Message -----
From: "Bill and Marsha" <docyukon@ptcnet.net>
Subject: whalen strobe wire size
> How do you calculate wire size for flash tubes? I'm useing a HDACF
> Whalen power suply with A610 wingtip tubes and a A500 series taillight
> assy. Max. joules will be 42. Thanks Bill S. Pulsar III
>
Message 19
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| Subject: | Re: Starter Contactor |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 09:12 PM 12/19/2004 -0600, you wrote:
>--> AeroElectric-List message posted by: "Maureen & Bob Christensen"
><mchriste@danvilletelco.net>
>
>This may be a stupid question . . .
>
>Is there a up or down to a (Van's) starter contactor . . . mine comes closer
>than I like to the engine mount (RV-8) when it's mounted with the terminals
>down . . . I talked a another builder who had mounted his that way
>(terminals down) and he had heard G forces (causing the starter to run)
>during aerobatics may be a factor when it's mounted terminal up.
Complete EH (elephant hocky). G-loading on starter contactors
just doesn't happen. Especially if your contactor looks like . . .
http://www.aeroelectric.com/Pictures/s702wire.jpg
http://www.aeroelectric.com/Pictures/s702-1l.jpg
(and I hope it does). This contactor is usually mounted
on firewall with contacts facing forward where the
dreaded in-flight closure due to g-loading would occur
only if you hit a mountainside at cruise.
>Is the a problem with mounting the contactor terminals up?
I think I was at OSH when this hangar legend was born.
An air-show performer landed with a torn up starter
ring-gear and pinion. Everyone seemed to think that
he'd welded the contacts on the starter motor while
performing acts of daring do.
It's more likely that the contactor stuck when he started
the engine.
Bob . . .
--
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Message 20
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| Subject: | RE: Schematic Review |
--> AeroElectric-List message posted by: Ken Harrill <KHarrill@osa.state.sc.us>
Scott,
In my RV-6 I modified the "All Electric On a Budget" system such that the
SD-8 circuit includes a small .8(that's 8/10ths)AH battery and is completely
independent of the main electrical system(and main battery). The system has
worked flawlessly for almost 400 hours now. The battery is about the size
of a deck of cards and is widely available.
Ken Harrill
Rv-6,
Columbia, SC
-----Original Message-----
From: swmat@cox.net [mailto:swmat@cox.net]
Subject: AeroElectric-List: RE: Schematic Review
--> AeroElectric-List message posted by: <swmat@cox.net>
-snip-
The single battery dual alternator system cannot tolerate a battery
failure because of the reliance on the battery for alternator output.
This design cannot tolerate a battery wiring failure.
--Scott
San Diego, CA
Message 21
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| Subject: | Re: whalen strobe wire size |
--> AeroElectric-List message posted by: "Joel Jacobs" <jj@sdf.lonestar.org>
Since you bumped this thread a couple times and none have answered I'll give
it a shot. I don't think the wire size is too important here. The duty
cycle is low and the power to the strobe cannot be more than the power to
the power supply so the same gauge you used to wire to the supply would
surely work between the supply and the strobe. Actually the average current
to the strobe tube is likely much less because the voltage is high. I made
a cable for mine that is about 3 feet long with 24ga and it's fine.
That being said, I think considerations more important than gage are
insulation ratings and shielding. What I used was just plain old 600v and
it's working but I'm keeping my eye out for some higher voltage stuff - I'd
be more comfortable with 1kv or more..
Joel Jacobs
----- Original Message -----
From: "Bill and Marsha" <docyukon@ptcnet.net>
Subject: AeroElectric-List: Re: whalen strobe wire size
> --> AeroElectric-List message posted by: "Bill and Marsha"
<docyukon@ptcnet.net>
>
>
> ----- Original Message -----
> From: "Bill and Marsha" <docyukon@ptcnet.net>
> To: <aeroelectric-list@matronics.com>
> Subject: whalen strobe wire size
>
>
> > How do you calculate wire size for flash tubes? I'm useing a HDACF
> > Whalen power suply with A610 wingtip tubes and a A500 series taillight
> > assy. Max. joules will be 42. Thanks Bill S. Pulsar III
> >
>
>
Message 22
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| Subject: | Re: Starter Contactor |
--> AeroElectric-List message posted by: "Maureen & Bob Christensen" <mchriste@danvilletelco.net>
Thanks Bob,
I guess I'm a "stray" . . . it look pretty much like this one.
http://www.vansaircraft.com/cgi-bin/catalog.cgi?ident=1103566372-394-261&browse=electrical&product=start-sw
but I'm betting it will work in either position!
Bob
----- Original Message -----
From: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
Subject: AeroElectric-List: Re: Starter Contactor
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<b.nuckolls@cox.net>
>
> At 09:12 PM 12/19/2004 -0600, you wrote:
>
> >--> AeroElectric-List message posted by: "Maureen & Bob Christensen"
> ><mchriste@danvilletelco.net>
> >
> >This may be a stupid question . . .
> >
> >Is there a up or down to a (Van's) starter contactor . . . mine comes
closer
> >than I like to the engine mount (RV-8) when it's mounted with the
terminals
> >down . . . I talked a another builder who had mounted his that way
> >(terminals down) and he had heard G forces (causing the starter to run)
> >during aerobatics may be a factor when it's mounted terminal up.
>
> Complete EH (elephant hocky). G-loading on starter contactors
> just doesn't happen. Especially if your contactor looks like . . .
>
> http://www.aeroelectric.com/Pictures/s702wire.jpg
>
> http://www.aeroelectric.com/Pictures/s702-1l.jpg
>
> (and I hope it does). This contactor is usually mounted
> on firewall with contacts facing forward where the
> dreaded in-flight closure due to g-loading would occur
> only if you hit a mountainside at cruise.
>
> >Is the a problem with mounting the contactor terminals up?
>
> I think I was at OSH when this hangar legend was born.
> An air-show performer landed with a torn up starter
> ring-gear and pinion. Everyone seemed to think that
> he'd welded the contacts on the starter motor while
> performing acts of daring do.
>
> It's more likely that the contactor stuck when he started
> the engine.
>
> Bob . . .
>
>
> --
> No virus found in this outgoing message.
> Checked by AVG Anti-Virus.
>
>
Message 23
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| Subject: | Re: Starter Contactor |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 07:53 PM 12/20/2004 -0600, you wrote:
>--> AeroElectric-List message posted by: "Maureen & Bob Christensen"
><mchriste@danvilletelco.net>
>
>Thanks Bob,
>
>I guess I'm a "stray" . . . it look pretty much like this one.
>http://www.vansaircraft.com/cgi-bin/catalog.cgi?ident=1103566372-394-261&browse=electrical&product=start-sw
>but I'm betting it will work in either position!
>
>Bob
I believe you are correct.
Bob . . .
--
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Checked by AVG Anti-Virus.
Message 24
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| Subject: | Re: Starter Contactor |
--> AeroElectric-List message posted by: "Scott Jackson" <jayeandscott@telus.net>
> It's more likely that the contactor stuck when he started
> the engine.
>
Just curious what the cockpit indications would be that this had happened.
Does the starter become an unwilling generator? Would anything show on the
voltmeter or ammeter? I have wired in a "STRTR PWRD" annunciator that senses
power downstream of the starter relay, and hoped that it would stay lit if
the starter hung up.
I don't know if it would if the contactor operated normally but the starter
bendix stayed engaged to the ring gear.
Scott in VAncouver--
> No virus found in this outgoing message.
> Checked by AVG Anti-Virus.
>
>
>
Message 25
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| Subject: | OV and Vans 60amp Alternator was 55 Amp Suzuki Alternator |
--> AeroElectric-List message posted by: Bobby Hester <bhester@hopkinsville.net>
John Crate wrote:
>--> AeroElectric-List message posted by: "John Crate" <john.crate@encode.com>
>
>
>Question 2
>My plan is to use the OVM-14 with the requisite contactor for over-voltage
>protection as per the Aeroelectric book/drawings. Reading a warning on
>Van's web page about over-voltage protection on their 60 amp internally
>regulated alternator now has me worried. In bright red letters it states:
>Warning!
>The internally regulated 60 ampere alternator should not be used with
>overvoltage protection systems. If you open the charging circuit while it is
>in operation, it will destroy the regulator.
>I am now confused more than normal. Is this something I should be worried
>about with respect to my particular alternator and planned application?
>
>
John did you get any responses to this question? I'd like to here them!
--
Surfing the Web from Hopkinsville, KY
Visit my web site at: http://www.geocities.com/hester-hoptown/RVSite/
RV7A Slowbuild wings-QB Fuse :-)
Message 26
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| Subject: | Re: Starter Contactor |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 06:48 PM 12/20/2004 -0800, you wrote:
>--> AeroElectric-List message posted by: "Scott Jackson"
><jayeandscott@telus.net>
>
>
> > It's more likely that the contactor stuck when he started
> > the engine.
> >
>Just curious what the cockpit indications would be that this had happened.
>Does the starter become an unwilling generator?
No . . .
> Would anything show on the
>voltmeter or ammeter? I have wired in a "STRTR PWRD" annunciator that senses
>power downstream of the starter relay, and hoped that it would stay lit if
>the starter hung up.
A loadmeter would show an extra-ordinary load on the alternator.
Some spam cans have STARTER ENERGIZED lights that monitor downstream
side of contactor.
>I don't know if it would if the contactor operated normally but the starter
>bendix stayed engaged to the ring gear.
Modern starters don't use internally engaged pinion gears
(Bendix) rather a directly engaged pinion driven from a
combination contactor/solenoid. See
http://aeroelectric.com/articles/strtctr.pdf
Modern starters have overrun clutches that prevent the engine
from driving the starter motor after the engine starts. This
prevents the engine from damaging the motor by overspeeding
it. However, this clutch is not designed for long periods
of operation in the overrunning disconnect mode. I'm not
sure if the Bendix pinion assembly has a real clutch. I suspect
the Bendix pinion's engagement spiral would tend to withdraw
the pinion gear during an overruning situation. In
any case, a stuck contactor that goes undetected will
keep an intermittent duty motor operating continuously
and may keep the pinion gear engaged.
It's important that one use a REAL starter contactor
(intermittent duty) and it's a good idea to put a warning
light on the contactor's "I" terminal as suggested
in:
http://www.aeroelectric.com/Pictures/s702wire.jpg
Bob . . .
--
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Message 27
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| Subject: | Re: Starter Contactor |
--> AeroElectric-List message posted by: "Scott Jackson" <jayeandscott@telus.net>
thanks again for the timely and informative answer, Sir.
----- Original Message -----
From: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
Subject: AeroElectric-List: Re: Starter Contactor
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
> <b.nuckolls@cox.net>
>
> At 06:48 PM 12/20/2004 -0800, you wrote:
>
>>--> AeroElectric-List message posted by: "Scott Jackson"
>><jayeandscott@telus.net>
>>
>>
>> > It's more likely that the contactor stuck when he started
>> > the engine.
>> >
>>Just curious what the cockpit indications would be that this had happened.
>>Does the starter become an unwilling generator?
>
> No . . .
>
>
>> Would anything show on the
>>voltmeter or ammeter? I have wired in a "STRTR PWRD" annunciator that
>>senses
>>power downstream of the starter relay, and hoped that it would stay lit if
>>the starter hung up.
>
> A loadmeter would show an extra-ordinary load on the alternator.
> Some spam cans have STARTER ENERGIZED lights that monitor downstream
> side of contactor.
>
>
>>I don't know if it would if the contactor operated normally but the
>>starter
>>bendix stayed engaged to the ring gear.
>
> Modern starters don't use internally engaged pinion gears
> (Bendix) rather a directly engaged pinion driven from a
> combination contactor/solenoid. See
>
> http://aeroelectric.com/articles/strtctr.pdf
>
> Modern starters have overrun clutches that prevent the engine
> from driving the starter motor after the engine starts. This
> prevents the engine from damaging the motor by overspeeding
> it. However, this clutch is not designed for long periods
> of operation in the overrunning disconnect mode. I'm not
> sure if the Bendix pinion assembly has a real clutch. I suspect
> the Bendix pinion's engagement spiral would tend to withdraw
> the pinion gear during an overruning situation. In
> any case, a stuck contactor that goes undetected will
> keep an intermittent duty motor operating continuously
> and may keep the pinion gear engaged.
>
> It's important that one use a REAL starter contactor
> (intermittent duty) and it's a good idea to put a warning
> light on the contactor's "I" terminal as suggested
> in:
>
> http://www.aeroelectric.com/Pictures/s702wire.jpg
>
> Bob . . .
>
>
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>
>
>
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