Today's Message Index:
----------------------
1. 02:36 AM - Battery failure -- lessons and questions (Frank & Dorothy)
2. 04:02 AM - Re: Battery failure -- lessons and questions on dbmail-mx1 (KITFOXZ@aol.com)
3. 07:10 AM - Re: 11868 Linderman (Robert L. Nuckolls, III)
4. 07:17 AM - Re: Battery failure -- lessons and questions on dbm (earl_schroeder@juno.com)
5. 08:32 AM - Re: Rotary Switch- solution found (jerb)
6. 09:04 AM - Re: Battery failure -- lessons and questions (Robert McCallum)
7. 09:43 AM - Re: Z13a Pre-flight alt test procedure? (Mike Holland)
8. 11:29 AM - Re: Battery failure -- lessons and questions (Paul Messinger)
9. 11:29 AM - turning off an internally regulated alternator (Paul Messinger)
10. 12:49 PM - Re: turning off an internally regulated alternator (Alex Peterson)
11. 01:12 PM - Re: turning off an internally regulated alternator (Paul Messinger)
12. 01:16 PM - Re: turning off an internally regulated alternator (Ed Anderson)
13. 01:28 PM - Re: Re: Load dump comments (Vincent Welch)
14. 01:36 PM - Re: turning off an internally regulated alternator (Paul Messinger)
15. 01:36 PM - Re: turning off an internally regulated alternator (Alex Peterson)
16. 01:52 PM - Load Dump Question (Vincent Welch)
17. 02:00 PM - OVP current limiting (Paul Messinger)
18. 02:02 PM - Pilot stick grip priority options rev B (Mark Banus)
19. 02:30 PM - Re: Load Dump Question (Paul Messinger)
20. 02:30 PM - Re: turning off an internally regulated alternator (Paul Messinger)
21. 03:11 PM - Garmin/Microencoder wiring question (Dan O'Brien)
22. 03:23 PM - General radio grounding question (Dan O'Brien)
23. 04:03 PM - Re: Garmin/Microencoder wiring question (Wayne Sweet)
24. 04:06 PM - Re: General radio grounding question (Wayne Sweet)
25. 04:20 PM - Re: Load Dump Question (Robert L. Nuckolls, III)
26. 04:44 PM - Re: Load Dump Question (Vincent Welch)
27. 06:39 PM - Re: Garmin/Microencoder wiring question (Dan O'Brien)
28. 06:44 PM - Re: General Wiring Question (Dan O'Brien)
29. 07:04 PM - Re: Re: Garmin/Microencoder wiring question (Wayne Sweet)
30. 07:20 PM - Re: Re: General Wiring Question (Wayne Sweet)
Message 1
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| Subject: | Battery failure -- lessons and questions |
on dbmail-mx1
--> AeroElectric-List message posted by: Frank & Dorothy <frankv@infogen.net.nz>
Hi,
Thought you guys might benefit from my experience today with my car
battery (at an air show, so it is aviation related :-) And there are
some bits of what I think are aeroelectric technology information.
Anyone not wanting to read my screeds should skip directly to LESSONS.
I recently installed an engine immobiliser after my car disappeared
overnight a couple of times (the plane project is in the garage). When
the car wouldn't start a couple of times over the last month or two, I
put it down to a not-too-well setup cheap immobiliser. When the car
started after a couple of twiddles with the immobiliser wires, that
confirmed it.
Today though, at an airshow about 2 hours drive from home, it wouldn't
crank again. :-( :-( Just a buzzing series of clicks from the
immobiliser relay. Twiddled the wires. Still no go. Tried the electric
windows -- they went down OK, but still no cranking. Disconnected the
immobiliser entirely. No help. Hmmm... borrowed some jumper leads, and
persuaded the guy on the next-door car in the parking lot to help out
with his alternator and battery. No go. Turning the key resulted in the
dash waring lights all going out. Now, this was really surprising.
someone came along with a diesel-powered car with a *big* battery...
STILL no go. By now, I'd decided that there was probably a fault in the
starter motor or ring gear :-( The kibbitzers (when waiting in a queue
to get out of an airfield carpark after a show, any entertainment is
welcome) and the hassle of somehow getting home, and then coming back
the next day or even 2 days later, it being a holiday on Monday)
eventually persuaded me to try a new battery. I got a ride to the
nearest gas station, bought a battery (at an exorbitant price) and
borrowed a couple of spanners, and got back to the airfield and replaced
the battery.
Somewhat to my surprise, everything suddenly worked properly!
As I see it now, when the starter motor isn't turning, its coils have
less impedance/resistance than the rest of the circuitry in the car.
Hence, turning the key to 'start' would drop the voltage across the
warning lights so that they went out. But the battery couldn't provide
enough oomph to turn the starter motor, so from the battery's point of
view there was more or less a short circuit. I'm thinking that probably
one (or more) of the battery's cells has died, so the battery couldn't
provide 12.5V, and some reduced amount of current. (I kept the bad
battery, and will investigate it with voltmeter, etc tomorrow)
I still don't see why adding more oomph via external battery and jumper
leads didn't get the car started. I guess that somehow the dead cell in
the bad battery was providing some kind of low-resistance path for the
juice from the good battery to flow through, instead of through the
starter motor??? But there was no noticeable heating of the jumper
leads, or loading down of the running car which I'd expect in that
situation. Also, I'd expect (but didn't see) sparks when I attached the
last jumper leads.
Another question that I'm wondering about: How can putting jumper leads
on a car blow its computer (as I was warned about today)? Surely, from
the computer's point of view, it can't tell whether the flow of
electricity its receiving is coming from the car's own battery, an
external battery, or some combination of both? If 'surges of
electricity' are the culprit as someone contended today, then surely
disconnecting a near-dead battery and connecting a new fully-charged
battery is worse than jumpering the full battery across the near-dead
one? And what about the voltage transients when the alternator starts
up? Is this "putting jumper leads on a car blow its computer" just a myth?
BobN, I'd appreciate it if you would satisy my curiosity over the
physics of what happened today.
LESSONS:
1. When your battery suggests that it is about to die, take heed!
2. Somehow, a bad battery can prevent a parallel good battery from
working! This may be especially relevant for people installing dual
batteries in their aircraft -- if you can't isolate a bad battery, it
may prevent starting (or even take down the electrical system???) even
if you have a good battery (or perhaps even a running alternator???)
alongside.
Frank
Message 2
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| Subject: | Re: Battery failure -- lessons and questions on dbmail-mx1 |
--> AeroElectric-List message posted by: KITFOXZ@aol.com
In a message dated 1/22/2005 5:38:12 A.M. Eastern Standard Time,
frankv@infogen.net.nz writes:
LESSONS:
1. When your battery suggests that it is about to die, take heed!
2. Somehow, a bad battery can prevent a parallel good battery from
working! This may be especially relevant for people installing dual
batteries in their aircraft -- if you can't isolate a bad battery, it
may prevent starting (or even take down the electrical system???) even
if you have a good battery (or perhaps even a running alternator???)
alongside.
Frank
Hello Frank,
Your lesson # 1 is so very true! This is one reason that Bob always
preaches about replacing aircraft batteries on a regular interval. The battery
is
the most unpredictable component in your aircraft, and yet the most depended
upon.
An old battery can have a shorted cell, thus reducing the battery's voltage
to 10 volts. A jumper battery connected in parallel across this bad 10 volt
battery will often be unable to boost the system voltage enough to start your
engine. This is why it is a good idea to remove the battery in question
from the circuit, if a jump fails to get you going, and replace it with a known
good battery.
An old battery with a shorted cell will receive full charge current from the
charging system too as the voltage regulator pushes tons of current into
this bad battery trying to restore its voltage to 13.8. The excess charge
current will destroy the other cells in a short time.
I have never liked using an "immobilizer" type of device in any of my cars
for fear that the thing would fail to "make" my starting circuit on a cold and
rainy night. The shops that install them often use any number of poor
connection practices as they install these bottom dollar devices. I prefer to
not
have my starting circuit compromised in any way. A simple noise maker alarm
system is my choice. If the thief defeats the alarm or drives off with it
screaming, I say let it be. Any electronic theft deterrent is just that in my
opinion, a deterrent. The average thief is dumb and in a hurry for an easy
victim. Sure there are the pros out there working for chop shops and those
few guys will know how to start your car no matter what you have installed to
foil them.
John P. Marzluf
Columbus, Ohio
Kitfox Outback (out back in the garage)
Message 3
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| Subject: | Re: 11868 Linderman |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 04:24 AM 1/22/2005 +0000, you wrote:
>Below is the result of your inquiry. It was submitted by
>Lucas Linderman (linluc23@email.pct.edu) on Friday, January 21, 2005 at
>20:24:58
>
>Friday, January 21, 2005
>
>Lucas Linderman
>
>,
>Email: linluc23@email.pct.edu
>Comments/Questions: Mr. Nuckolls,
> My name is Luke Linderman and I am senior at the Pennsylvania College
> of Technology in Williamsport Pennsylvania. I am enrolled in the Bachelor
> of Aviation Maintenance with the first two years concentrating on the A&P
> License and the last two on Avionics. As a requirement to graduate we
> have to do an intensive senior project. For my project I am designing and
> electrical system install in RV-7/7A. The homebuilder is currently
> desiding on whether to go with Figure Z-12 or Z-13. I was just wondering
> if those diagrams are just basic idea or if the wires are already set at
> the right size?
Electrical system architecture for light aircraft has not
materially changed since the C-140 and C-170 got their
first generators and batteries installed in the late 40s.
The only real "bump up" in electrical system capabilities
came in the late 60s when generators were replaced with
alternators and the avionics master switch and bus were
added for the wrong reasons.
The Z-figures were crafted to offer some choices for
system architecture allowing a builder to optimize
performance, minimize parts count, and craft simple,
failure tolerant operation tailored to an airplane's mission.
NONE of the wire sizes, breaker/fuse sizes, or part
numbers of components should be construed as recommended
for any particular design. I would begin the design for
a new aircraft by conducting a load analysis. There is
a blank form you can download at:
http://www.aeroelectric.com/articles/LoadAnalysis.pdf
. . . one page for each bus of your selected architecture.
List every electro-whizzie that draws power from the system
and deduce its requirements under all the flight conditions
noted across the top of the form.
This exercise will help you size wires, circuit protection,
batteries and alternators.
> I thank you for your time and look forward to talking to you in the
> future about this if possible.
Please join us on the AeroElectric-List which is described
at:
http://aeroelectric.com/consulting.html
This service is free and may be joined or abandoned
at any time. Participation on this list will put you
in contact with many capable builders/designers who
share your interests. I would encourage you to
pass this invitation along to your fellow students
as well.
As you look forward to your own career, please know
that the best way to advance the state of your own
art is to TEACH IT. The AeroElectric-List is a good
place to acquire those skills by taking advantage of
all that folks on the List are eager and willing to
share. As your personal knowledge and skills grow,
you will have much to offer others.
When we take the time to share our particular stock
of simple ideas and discuss the ways in which those
ideas can be assembled into practical inventions, we
ALL become teachers in the finest sense of the word.
Bob . . .
Message 4
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| Subject: | Re: Battery failure -- lessons and questions on dbm |
ail-mx1
--> AeroElectric-List message posted by: "earl_schroeder@juno.com" <earl_schroeder@juno.com>
In an attempt to squeeze out more life from an old car, I installed an 'aircraft
approved master relay' which completely disconnects the battery as it does in
aircraft. It solved the very intermittent battery draining situation which
I was unable to find. A 'hidden' master switch also serves as an 'immobilizer'
although if someone wants this old car... Now my digital clock serves as a
time-in-route. Earl
-- KITFOXZ@aol.com wrote:
--> AeroElectric-List message posted by: KITFOXZ@aol.com
In a message dated 1/22/2005 5:38:12 A.M. Eastern Standard Time,
frankv@infogen.net.nz writes:
LESSONS:
1. When your battery suggests that it is about to die, take heed!
2. Somehow, a bad battery can prevent a parallel good battery from
working! This may be especially relevant for people installing dual
batteries in their aircraft -- if you can't isolate a bad battery, it
may prevent starting (or even take down the electrical system???) even
if you have a good battery (or perhaps even a running alternator???)
alongside.
Frank
Hello Frank,
Your lesson # 1 is so very true! This is one reason that Bob always
preaches about replacing aircraft batteries on a regular interval. The battery
is
the most unpredictable component in your aircraft, and yet the most depended
upon.
An old battery can have a shorted cell, thus reducing the battery's voltage
to 10 volts. A jumper battery connected in parallel across this bad 10 volt
battery will often be unable to boost the system voltage enough to start your
engine. This is why it is a good idea to remove the battery in question
from the circuit, if a jump fails to get you going, and replace it with a known
good battery.
An old battery with a shorted cell will receive full charge current from the
charging system too as the voltage regulator pushes tons of current into
this bad battery trying to restore its voltage to 13.8. The excess charge
current will destroy the other cells in a short time.
I have never liked using an "immobilizer" type of device in any of my cars
for fear that the thing would fail to "make" my starting circuit on a cold and
rainy night. The shops that install them often use any number of poor
connection practices as they install these bottom dollar devices. I prefer to
not
have my starting circuit compromised in any way. A simple noise maker alarm
system is my choice. If the thief defeats the alarm or drives off with it
screaming, I say let it be. Any electronic theft deterrent is just that in my
opinion, a deterrent. The average thief is dumb and in a hurry for an easy
victim. Sure there are the pros out there working for chop shops and those
few guys will know how to start your car no matter what you have installed to
foil them.
John P. Marzluf
Columbus, Ohio
Kitfox Outback (out back in the garage)
Message 5
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| Subject: | Re: Rotary Switch- solution found |
--> AeroElectric-List message posted by: jerb <ulflyer@verizon.net>
Question - is this switch, switching AC or DV voltages - switches rated for
AC normally will only handle a fraction of their current rating when
operated in a DC application. It has to do with the type of contacts used
in each switch, DC switches cost more to make because of the material that
has to be used to reduce arcing when contacts break and resist welding. AC
switches take advantage of the zero point crossing of the AC swine wave to
reducing arching effect when contact break thus allow the use of lower cost
materials for the contacts.
jerb
At 10:22 PM 1/21/05 -0600, you wrote:
>--> AeroElectric-List message posted by: Bonnie & August Lehmann
><blehmann@pris.bc.ca>
>
>Just to say thank you to Leo Corbalis, Rob Prior, and Sigmo for their leads
>and suggestions to a replacement of a 25A, 120VAC rotary selector switch.
>None of the sources had anything of a high enough capacity, and as a total
>greenhorn in electrical or electronic matters, I hesitated going the
>relay/contacter route.
>
>Then my better half came up with a solution after she examined the broken
>switch, and that was to use parts of a sheet of Lexan I happen to have
>laying around to replace the broken face of the switch. A full day later,
>and voila, its repaired and working! Now we will survive the early stages
>of the 37th ice age this year.
>
>Many thanks to the List and the rapid responses it created to our dilemma.
>
>August
>
>
Message 6
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| Subject: | Re: Battery failure -- lessons and questions |
on dbmail-mx1
--> AeroElectric-List message posted by: Robert McCallum <robert.mccallum2@sympatico.ca>
Frank & Dorothy wrote:
>--> AeroElectric-List message posted by: Frank & Dorothy <frankv@infogen.net.nz>
>
>Hi,
>
>Thought you guys might benefit from my experience today with my car
>battery
>I recently installed an engine immobiliser after my car disappeared
>overnight a couple of times
>
>
Possibly unrelated.
> I got a ride to the
>nearest gas station, bought a battery (at an exorbitant price) and
>borrowed a couple of spanners, and got back to the airfield and replaced
>the battery.
>
>
Re-attaching a couple of connections in the process.
>Somewhat to my surprise, everything suddenly worked properly!
>
>
Not necessarily surprising.
>As I see it now, when the starter motor isn't turning, its coils have
>less impedance/resistance than the rest of the circuitry in the car.
>Hence, turning the key to 'start' would drop the voltage across the
>warning lights so that they went out. But the battery couldn't provide
>enough oomph to turn the starter motor, so from the battery's point of
>view there was more or less a short circuit.
>
Very true. Almost always happens with a "dead" battery.
> I'm thinking that probably
>one (or more) of the battery's cells has died, so the battery couldn't
>provide 12.5V, and some reduced amount of current. (I kept the bad
>battery, and will investigate it with voltmeter, etc tomorrow)
>
>
Possibly but not necessarily true. Remember those connections you
renewed when you changed batteries? An extremely high resistant
connection will display exactly the symptoms you describe. I can't count
the number of times that I have encountered people with non starting
cars with exactly the symptoms you describe whom I've been able to get
started by simply disconnecting the battery cables, cleaning the
connections and re-attaching them. Instant cure. Corrosion on the
terminals of neglected batteries condemns many perfectly good batteries
to the scrap heap. Part of battery maintenance is keeping the terminals
clean, especially here in the "Great White North" where salt used on the
roads in winter corrodes connections very rapidly.
>I still don't see why adding more oomph via external battery and jumper
>leads didn't get the car started. I guess that somehow the dead cell in
>the bad battery was providing some kind of low-resistance path for the
>juice from the good battery to flow through, instead of through the
>starter motor??? But there was no noticeable heating of the jumper
>leads, or loading down of the running car which I'd expect in that
>situation. Also, I'd expect (but didn't see) sparks when I attached the
>last jumper leads.
>
>
These comments, (no sparks, no heating of the leads, no loading of the
running car etc.) usually indicates a poorly connected cable or a cable
connected to a corroded battery terminal displaying the above mentioned
high resistance. "Most" battery cables which the average person has are
totally useless. The average hardware/automotive store cables are of
MUCH too small a gauge. A useful jumper cable set should be at least #2
gauge copper wire or heavier with solid copper clamps attached to
brightly cleaned connections on both the booster and boosted cars.
(vehicles) The "cheap" cables properly connected WILL heat up. This heat
is energy not available for starting. No heat and /or no spark and no
loading of the booster car means no connection, no current flow hence no
boost.
>Another question that I'm wondering about: How can putting jumper leads
>on a car blow its computer (as I was warned about today)? Surely, from
>the computer's point of view, it can't tell whether the flow of
>electricity its receiving is coming from the car's own battery, an
>external battery, or some combination of both? If 'surges of
>electricity' are the culprit as someone contended today, then surely
>disconnecting a near-dead battery and connecting a new fully-charged
>battery is worse than jumpering the full battery across the near-dead
>one? And what about the voltage transients when the alternator starts
>up? Is this "putting jumper leads on a car blow its computer" just a myth?
>
>
Generally happens if the boosted car battery is "dead" or disconnected
due to bad connections (see above) and you get the cables connected
backwards thus powering the computer with reverse polarity. Yes, this
can "blow" the computer. Properly connected cables will not cause a
problem just as your analysis suggests.
>BobN, I'd appreciate it if you would satisy my curiosity over the
>physics of what happened today.
>
>
Your turn Bob.
>LESSONS:
>1. When your battery suggests that it is about to die, take heed!
>
>
Good advice !
> <>2. Somehow, a bad battery can prevent a parallel good battery from
> working! This may be especially relevant for people installing dual
> batteries in their aircraft -- if you can't isolate a bad battery, it
> may prevent starting (or even take down the electrical system???) even
> if you have a good battery (or perhaps even a running
> alternator???)alongside.
Not usually, but, I suppose, sometimes possible.
> <>Frank
Bob McC
Message 7
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| Subject: | Re: Z13a Pre-flight alt test procedure? |
--> AeroElectric-List message posted by: "Mike Holland" <hollandm@pacbell.net>
Does your alternator have a built in regulator. Are you wired
per Z-24?
Yes (Vans 60amp) and Yes.
IF NOT . . . then there's nothing at risk for turning
the main alternator OFF and aux alternator ON during runup to
check your ignition system(s). If you have Z-24 and internally
regulated alternator, turn the main alternator OFF and aux alternator
ON at engine idle before runup . . . after run up and at engine idle,
turn aux alternator OFF and main alternator back ON. Don't
concern yourself with voltage readings while aux alternator
is ON . . . just not that the current output comes up. You might
want to consider running BOTH alternator leads through ONE
hall-effect sensor. Since the alternators are tested/used
independently from each other, the one current sensor can be
used to monitor functionality of both alternators.
Would have done that had the b-leads been in some proximity. The main alternator
is connected to the Z24 relay on the engine side, lower right, below the battery
case and the Aux alternator is high and it's lead goes through the firewall
to the regulator mounted inside. I'm using AmpLoc sensors for both so it
will interesting to see how easily they are to calibrate. There wired to the
Grand Rapid EIS using 2 of the available Aux inputs. 4.8 volts supplied. I won't
be concerned about accuracy so much as repeatability since i think if it
more as a benchmark and measure of day to day performance.
Thanks
Message 8
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| Subject: | Re: Battery failure -- lessons and questions |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
Another thing to consider.
There is a ground jumper from the engine block to the frame.
I had this come off and got either
(1) no starting or
(2) the lights going out
(3) or it worked just fine.
With the jumper missing your ground path is thru the wheel bearings etc
which are a variable resistor.
In any event fixing the ground jumper remover ALL the above problems for me.
Paul
----- Original Message -----
From: "Robert McCallum" <robert.mccallum2@sympatico.ca>
Subject: Re: AeroElectric-List: Battery failure -- lessons and questions on
dbmail-mx1
> --> AeroElectric-List message posted by: Robert McCallum
<robert.mccallum2@sympatico.ca>
>
> Frank & Dorothy wrote:
>
> >--> AeroElectric-List message posted by: Frank & Dorothy
<frankv@infogen.net.nz>
> >
> >Hi,
> >
> >Thought you guys might benefit from my experience today with my car
> >battery
> >I recently installed an engine immobiliser after my car disappeared
> >overnight a couple of times
> >
> >
> Possibly unrelated.
>
> > I got a ride to the
> >nearest gas station, bought a battery (at an exorbitant price) and
> >borrowed a couple of spanners, and got back to the airfield and replaced
> >the battery.
> >
> >
> Re-attaching a couple of connections in the process.
>
> >Somewhat to my surprise, everything suddenly worked properly!
> >
> >
> Not necessarily surprising.
>
> >As I see it now, when the starter motor isn't turning, its coils have
> >less impedance/resistance than the rest of the circuitry in the car.
> >Hence, turning the key to 'start' would drop the voltage across the
> >warning lights so that they went out. But the battery couldn't provide
> >enough oomph to turn the starter motor, so from the battery's point of
> >view there was more or less a short circuit.
> >
> Very true. Almost always happens with a "dead" battery.
>
> > I'm thinking that probably
> >one (or more) of the battery's cells has died, so the battery couldn't
> >provide 12.5V, and some reduced amount of current. (I kept the bad
> >battery, and will investigate it with voltmeter, etc tomorrow)
> >
> >
> Possibly but not necessarily true. Remember those connections you
> renewed when you changed batteries? An extremely high resistant
> connection will display exactly the symptoms you describe. I can't count
> the number of times that I have encountered people with non starting
> cars with exactly the symptoms you describe whom I've been able to get
> started by simply disconnecting the battery cables, cleaning the
> connections and re-attaching them. Instant cure. Corrosion on the
> terminals of neglected batteries condemns many perfectly good batteries
> to the scrap heap. Part of battery maintenance is keeping the terminals
> clean, especially here in the "Great White North" where salt used on the
> roads in winter corrodes connections very rapidly.
>
> >I still don't see why adding more oomph via external battery and jumper
> >leads didn't get the car started. I guess that somehow the dead cell in
> >the bad battery was providing some kind of low-resistance path for the
> >juice from the good battery to flow through, instead of through the
> >starter motor??? But there was no noticeable heating of the jumper
> >leads, or loading down of the running car which I'd expect in that
> >situation. Also, I'd expect (but didn't see) sparks when I attached the
> >last jumper leads.
> >
> >
> These comments, (no sparks, no heating of the leads, no loading of the
> running car etc.) usually indicates a poorly connected cable or a cable
> connected to a corroded battery terminal displaying the above mentioned
> high resistance. "Most" battery cables which the average person has are
> totally useless. The average hardware/automotive store cables are of
> MUCH too small a gauge. A useful jumper cable set should be at least #2
> gauge copper wire or heavier with solid copper clamps attached to
> brightly cleaned connections on both the booster and boosted cars.
> (vehicles) The "cheap" cables properly connected WILL heat up. This heat
> is energy not available for starting. No heat and /or no spark and no
> loading of the booster car means no connection, no current flow hence no
> boost.
>
> >Another question that I'm wondering about: How can putting jumper leads
> >on a car blow its computer (as I was warned about today)? Surely, from
> >the computer's point of view, it can't tell whether the flow of
> >electricity its receiving is coming from the car's own battery, an
> >external battery, or some combination of both? If 'surges of
> >electricity' are the culprit as someone contended today, then surely
> >disconnecting a near-dead battery and connecting a new fully-charged
> >battery is worse than jumpering the full battery across the near-dead
> >one? And what about the voltage transients when the alternator starts
> >up? Is this "putting jumper leads on a car blow its computer" just a
myth?
> >
> >
> Generally happens if the boosted car battery is "dead" or disconnected
> due to bad connections (see above) and you get the cables connected
> backwards thus powering the computer with reverse polarity. Yes, this
> can "blow" the computer. Properly connected cables will not cause a
> problem just as your analysis suggests.
>
> >BobN, I'd appreciate it if you would satisy my curiosity over the
> >physics of what happened today.
> >
> >
> Your turn Bob.
>
> >LESSONS:
> >1. When your battery suggests that it is about to die, take heed!
> >
> >
> Good advice !
>
> > <>2. Somehow, a bad battery can prevent a parallel good battery from
> > working! This may be especially relevant for people installing dual
> > batteries in their aircraft -- if you can't isolate a bad battery, it
> > may prevent starting (or even take down the electrical system???) even
> > if you have a good battery (or perhaps even a running
> > alternator???)alongside.
>
> Not usually, but, I suppose, sometimes possible.
>
> > <>Frank
>
>
> Bob McC
>
>
Message 9
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| Subject: | turning off an internally regulated alternator |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
> then there's nothing at risk for turning
> the main alternator OFF and aux alternator ON during runup to
> check your ignition system(s).
ALL the Jap internally regulated alternators INCL ND (that I have looked at
and that is quite a few but no where all types and ND alone has several
different designs) cannot be turned off once turned on and running.
Toggle the alt ON OFF connection all you want but the internal regulator is
LATCHED on.
IS vans ND different??
Its possible to disconnect the "B" lead using the CB but that is
disconnecting not turning off the alternator.
Paul
Message 10
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| Subject: | turning off an internally regulated alternator |
--> AeroElectric-List message posted by: "Alex Peterson" <alexpeterson@earthlink.net>
> ALL the Jap internally regulated alternators INCL ND (that I
> have looked at and that is quite a few but no where all types
> and ND alone has several different designs) cannot be turned
> off once turned on and running.
>
> Toggle the alt ON OFF connection all you want but the
> internal regulator is LATCHED on.
>
> IS vans ND different??
Paul,
I have an internally regulated ND 40amp alternator (Niagara Air Parts) which
came with my Aerosport engine. The above statement is not true in my case.
My master switch is a three position setup, when the engine is running and I
turn off the alternator (which disconnects the 5 amp supply to the
alternator), the bus voltage drops to battery voltage. Turn it on, 14
volts, off 12, etc..
Alex Peterson
RV6-A 569 hours
Maple Grove, MN
http://www.home.earthlink.net/~alexpeterson/
Message 11
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| Subject: | Re: turning off an internally regulated alternator |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
Thanks that clears that up. I wonder is your a rebuilt unit or OEM original
as the internal regulators might be wired differently. ALL my investigations
were on alternators off autos and none from rebuilders.
Paul
----- Original Message -----
From: "Alex Peterson" <alexpeterson@earthlink.net>
Subject: RE: AeroElectric-List: turning off an internally regulated
alternator
> --> AeroElectric-List message posted by: "Alex Peterson"
<alexpeterson@earthlink.net>
>
> > ALL the Jap internally regulated alternators INCL ND (that I
> > have looked at and that is quite a few but no where all types
> > and ND alone has several different designs) cannot be turned
> > off once turned on and running.
> >
> > Toggle the alt ON OFF connection all you want but the
> > internal regulator is LATCHED on.
> >
> > IS vans ND different??
>
> Paul,
>
> I have an internally regulated ND 40amp alternator (Niagara Air Parts)
which
> came with my Aerosport engine. The above statement is not true in my
case.
> My master switch is a three position setup, when the engine is running and
I
> turn off the alternator (which disconnects the 5 amp supply to the
> alternator), the bus voltage drops to battery voltage. Turn it on, 14
> volts, off 12, etc..
>
> Alex Peterson
> RV6-A 569 hours
> Maple Grove, MN
>
> http://www.home.earthlink.net/~alexpeterson/
>
>
Message 12
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| Subject: | Re: turning off an internally regulated alternator |
--> AeroElectric-List message posted by: "Ed Anderson" <eanderson@carolina.rr.com>
I originally thought my auto alternator was controllable by the voltage to
its field coil. I even convinced myself of this by pulling the 5 amp field
coil circuit breaker and starting the engine - sure enough only battery busy
voltage. I then pushed in the circuit breaker and sure enough 14.2 volts
from the alternator. I then again pulled the alternator field coil circuit
breaker and Whoa! it stated at 14.2 volts. A little research on alternators
revealed the fact that once the alternator is producing voltage it no longer
needs external voltage to the field coil (apparently its provided
internally). So once this initial external "boot strap" voltage is provided
and the alternator starts producing - the external voltage is no longer
required and the alternator can not be disabled by removing it (at least for
my alternator and most auto alternators with internal regulation). Your
mileage may vary
Ed Anderson
RV-6A N494BW
Matthew, NC
----- Original Message -----
From: "Alex Peterson" <alexpeterson@earthlink.net>
Subject: RE: AeroElectric-List: turning off an internally regulated
alternator
> --> AeroElectric-List message posted by: "Alex Peterson"
<alexpeterson@earthlink.net>
>
> > ALL the Jap internally regulated alternators INCL ND (that I
> > have looked at and that is quite a few but no where all types
> > and ND alone has several different designs) cannot be turned
> > off once turned on and running.
> >
> > Toggle the alt ON OFF connection all you want but the
> > internal regulator is LATCHED on.
> >
> > IS vans ND different??
>
> Paul,
>
> I have an internally regulated ND 40amp alternator (Niagara Air Parts)
which
> came with my Aerosport engine. The above statement is not true in my
case.
> My master switch is a three position setup, when the engine is running and
I
> turn off the alternator (which disconnects the 5 amp supply to the
> alternator), the bus voltage drops to battery voltage. Turn it on, 14
> volts, off 12, etc..
>
> Alex Peterson
> RV6-A 569 hours
> Maple Grove, MN
>
> http://www.home.earthlink.net/~alexpeterson/
>
>
Message 13
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| Subject: | Re: Load dump comments |
--> AeroElectric-List message posted by: "Vincent Welch" <welchvincent@hotmail.com>
Paul,
What wattage rating would the 1/2 ohm resistor require?
Vince
>From: "Paul Messinger" <paulm@olypen.com>
>Reply-To: aeroelectric-list@matronics.com
>To: <aeroelectric-list@matronics.com>
>Subject: Re: AeroElectric-List: Re: Load dump comments
>Date: Sat, 8 Jan 2005 12:59:16 -0800
>
>--> AeroElectric-List message posted by: "Paul Messinger"
><paulm@olypen.com>
>
>Its wired exactly as Bob shows.
>
>The power path is thru the CB that powers the relay (in the case of a "B"
>lead the contactor) and the crow bar shorts the CB to ground and the 400
>amps is thru the wiring and thru the CB and OVP SCR. There is no HI current
>thru the field.
>
>Draw a wire from the load side of the CB to ground (thats the OVP). The
>resulting circuit is the battery to the CB to the OVP to ground. The OVP
>tripps and its scr shorts the OVP to ground. Net result is the CB is
>directly across the battery plus wiring. The modern battery will provide
>more than 1000 amps (some closer to 2000 amps) across the CB with very
>short
>leads. One solution is a 1/8 to 1/2 ohm resistor in the OVP shorting path
>to
>limit current and still blow the CB.
>
>I got 730 amps with shorter but realistic leads and the Powersonic 12v18ah
>battery that Bob promotes. Far cry from a Gill flooded cell acft battery.
>
>I tried 3 different popular 5 amp CB brands and all showed at least 50 ms
>to
>open. (and that is when they are warmed up). After a couple of hours at
>rest
>the CB can take more than 80MS to trip. Yes they are that slow.
>
>Paul
>
>----- Original Message -----
>From: "Kevin Horton" <khorton01@rogers.com>
>To: <aeroelectric-list@matronics.com>
>Subject: Re: AeroElectric-List: Re: Load dump comments
>
>
> > --> AeroElectric-List message posted by: Kevin Horton
><khorton01@rogers.com>
> >
> > I'm interested as to which two items the crowbar was shorting when
> > these large currents were measured. I'm assuming this is a different
> > application than the crowbar OV protection that Bod espouses, where
> > the crowbar shorts out the field circuit, popping a 5A CB. I can't
> > imagine how 400 to 700 amps could be generated in the field circuit
> > before the 5A CB popped. Are CBs that slow to trip? Or, was this a
> > different application of a crowbar?
> >
> > Kevin Horton
> >
> > >--> AeroElectric-List message posted by: "Paul Messinger"
><paulm@olypen.com>
> > >
> > >The huge current loop during a shorting crowbar event generates a large
> > >magnetic field that can magnetize steel and mess up your compass
> > >calibration.
> > >
> > >I got 400 amps with longer that likely wires. When I simulated my
>aircraft
> > >wiring I got over 700 amps.
> > >
> > >Measurements were made with calibrated equipment. as well as being
> > >repeatable.
> > >
> > >If this does not bother you, be my guest.
> > >
> > >Paul
> > >
> > >
> > >> Sure that sounds scary but I'll wait for the report before getting
> > >> concerned. With 6 feet of 18awg wire in series with a C/B, an SCR,
>and
> > >> several connections it may be possible to get a couple of hundred
>amps
> > >> of instantaneous current flowing but so what? It is drawing down the
> > >> voltage which is what we want.
> > >>
> > >> The interesting thing to me is a nuisance trip. It sounds like it is
> > >> possible to ramp up the alternator output during the delay (40 ms?)
> > >> waiting for the OV contactor to open. However I haven't seen any
>reason
> > > > to be concerned about that yet and I will await the report.
> >
> >
>
>
Message 14
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| Subject: | Re: turning off an internally regulated alternator |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
Your alternator internal regulator sounds like what I have seen. There is an
internal path from the "B" lead that powers the regulator as well as
internal regulator logic that "latches" the regulator in the ON condition
Clearly different brands and differenced between types of the same brand are
out there.
Both of the below messages demonstrate this.
Can anyone who has a Vans rebuilt ND alternator comment on how that version
works with respect to this thread.
Paul
----- Original Message -----
From: "Ed Anderson" <eanderson@carolina.rr.com>
Subject: Re: AeroElectric-List: turning off an internally regulated
alternator
> --> AeroElectric-List message posted by: "Ed Anderson"
<eanderson@carolina.rr.com>
>
> I originally thought my auto alternator was controllable by the voltage to
> its field coil. I even convinced myself of this by pulling the 5 amp
field
> coil circuit breaker and starting the engine - sure enough only battery
busy
> voltage. I then pushed in the circuit breaker and sure enough 14.2 volts
> from the alternator. I then again pulled the alternator field coil
circuit
> breaker and Whoa! it stated at 14.2 volts. A little research on
alternators
> revealed the fact that once the alternator is producing voltage it no
longer
> needs external voltage to the field coil (apparently its provided
> internally). So once this initial external "boot strap" voltage is
provided
> and the alternator starts producing - the external voltage is no longer
> required and the alternator can not be disabled by removing it (at least
for
> my alternator and most auto alternators with internal regulation). Your
> mileage may vary
>
> Ed Anderson
> RV-6A N494BW
> Matthew, NC
> ----- Original Message -----
> From: "Alex Peterson" <alexpeterson@earthlink.net>
> To: <aeroelectric-list@matronics.com>
> Subject: RE: AeroElectric-List: turning off an internally regulated
> alternator
>
>
> > --> AeroElectric-List message posted by: "Alex Peterson"
> <alexpeterson@earthlink.net>
> >
> > > ALL the Jap internally regulated alternators INCL ND (that I
> > > have looked at and that is quite a few but no where all types
> > > and ND alone has several different designs) cannot be turned
> > > off once turned on and running.
> > >
> > > Toggle the alt ON OFF connection all you want but the
> > > internal regulator is LATCHED on.
> > >
> > > IS vans ND different??
> >
> > Paul,
> >
> > I have an internally regulated ND 40amp alternator (Niagara Air Parts)
> which
> > came with my Aerosport engine. The above statement is not true in my
> case.
> > My master switch is a three position setup, when the engine is running
and
> I
> > turn off the alternator (which disconnects the 5 amp supply to the
> > alternator), the bus voltage drops to battery voltage. Turn it on, 14
> > volts, off 12, etc..
> >
> > Alex Peterson
> > RV6-A 569 hours
> > Maple Grove, MN
> >
> > http://www.home.earthlink.net/~alexpeterson/
> >
> >
>
>
Message 15
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| Subject: | turning off an internally regulated alternator |
--> AeroElectric-List message posted by: "Alex Peterson" <alexpeterson@earthlink.net>
Mine is (was) new five years ago. Call to confirm, but I seem to recall
that Aerosport Power got them from Niagara Air Parts. See
http://www.niagaraairparts.com/ 3/4's down the page.
Alex Peterson
> --> AeroElectric-List message posted by: "Paul Messinger"
> --> <paulm@olypen.com>
>
> Thanks that clears that up. I wonder is your a rebuilt unit
> or OEM original as the internal regulators might be wired
> differently. ALL my investigations were on alternators off
> autos and none from rebuilders.
>
> Paul
>
> ----- Original Message -----
> From: "Alex Peterson" <alexpeterson@earthlink.net>
> To: <aeroelectric-list@matronics.com>
> Subject: RE: AeroElectric-List: turning off an internally
> regulated alternator
>
>
> > --> AeroElectric-List message posted by: "Alex Peterson"
> <alexpeterson@earthlink.net>
> >
> > > ALL the Jap internally regulated alternators INCL ND (that I have
> > > looked at and that is quite a few but no where all types and ND
> > > alone has several different designs) cannot be turned off once
> > > turned on and running.
> > >
> > > Toggle the alt ON OFF connection all you want but the internal
> > > regulator is LATCHED on.
> > >
> > > IS vans ND different??
> >
> > Paul,
> >
> > I have an internally regulated ND 40amp alternator (Niagara
> Air Parts)
> which
> > came with my Aerosport engine. The above statement is not
> true in my
> case.
> > My master switch is a three position setup, when the engine
> is running
> > and
> I
> > turn off the alternator (which disconnects the 5 amp supply to the
> > alternator), the bus voltage drops to battery voltage.
> Turn it on, 14
> > volts, off 12, etc..
> >
> > Alex Peterson
> > RV6-A 569 hours
> > Maple Grove, MN
> >
> > http://www.home.earthlink.net/~alexpeterson/
> >
> >
>
>
> =========
> Matronics Forums.
> =========
> http://www.matronics.com/FAQ/AeroElectric-List.htm
> =========
>
>
>
>
>
Message 16
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| Subject: | Load Dump Question |
--> AeroElectric-List message posted by: "Vincent Welch" <welchvincent@hotmail.com>
Hey guys, I have been watching this "Battle Of The Titans" with great
interest. I have a question from one a bit lower down the food chain:)
It has always been my understanding that the purpose of the OV circuit was
to protect my avionics from a runaway alternator. The alternator or
regulator has already failed and the voltage is climbing. The crowbar opens
the circuit to limit prevent damage to my expensive avionics. The
alternator/regulator has already failed, its trash, so I open the B-lead
under load, I get a load dump event. So what? Why do I care about trying
to protect the alternator now?
I can understand limiting the crowbar circuit current and adding a resistor
sounds like a simple easy solution to that problem.
What am I missing here? Please further educate me.
Vince
Message 17
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|
| Subject: | OVP current limiting |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
New subject line above
First lets pick a resistance from the following table to suit your comfort.
OHM aprox current
0.1 120 amps
0.2 60 amps
0.3 40 amps
0.4 30 amps
0.5 24 amps
Any of the above resistance values will blow most CB's in about the same
time. Any value is better than a dead short plus wiring drops. (I get
400-700+ amps depending on wiring length etc and battery used with no series
resistor.)
I would recommend 0.2 to 0.4 ohms as reasonable compromise. Around 10 times
the CB rating ends up with the fastest possible trip time. Thus 50 amps is
more than enough for a 5 amp CB.
Wattage is not important but the resistors ability pass the current pulse is
the driving parameter. So a 1/2 watt might be OK, I would use a one watt to
be sure. Most any brand or type will work fine. If you made your OVP from
Bob's plans it can be added to the circuit, or simply added in line
externally.
I will have more comments on the Crowbar approach and how its different from
the classic short and blow a fuse or CB protecting avionics etc. Not quite
the same issues and concerns.
Paul
PS Thanks for asking
----- Original Message -----
From: "Vincent Welch" <welchvincent@hotmail.com>
Subject: Re: AeroElectric-List: Re: Load dump comments
> --> AeroElectric-List message posted by: "Vincent Welch"
<welchvincent@hotmail.com>
>
> Paul,
>
> What wattage rating would the 1/2 ohm resistor require?
>
> Vince
>
> >From: "Paul Messinger" <paulm@olypen.com>
> >Reply-To: aeroelectric-list@matronics.com
> >To: <aeroelectric-list@matronics.com>
> >Subject: Re: AeroElectric-List: Re: Load dump comments
> >Date: Sat, 8 Jan 2005 12:59:16 -0800
> >
> >--> AeroElectric-List message posted by: "Paul Messinger"
> ><paulm@olypen.com>
> >
> >Its wired exactly as Bob shows.
> >
> >The power path is thru the CB that powers the relay (in the case of a "B"
> >lead the contactor) and the crow bar shorts the CB to ground and the 400
> >amps is thru the wiring and thru the CB and OVP SCR. There is no HI
current
> >thru the field.
> >
> >Draw a wire from the load side of the CB to ground (thats the OVP). The
> >resulting circuit is the battery to the CB to the OVP to ground. The OVP
> >tripps and its scr shorts the OVP to ground. Net result is the CB is
> >directly across the battery plus wiring. The modern battery will provide
> >more than 1000 amps (some closer to 2000 amps) across the CB with very
> >short
> >leads. One solution is a 1/8 to 1/2 ohm resistor in the OVP shorting path
> >to
> >limit current and still blow the CB.
> >
> >I got 730 amps with shorter but realistic leads and the Powersonic
12v18ah
> >battery that Bob promotes. Far cry from a Gill flooded cell acft battery.
> >
> >I tried 3 different popular 5 amp CB brands and all showed at least 50 ms
> >to
> >open. (and that is when they are warmed up). After a couple of hours at
> >rest
> >the CB can take more than 80MS to trip. Yes they are that slow.
> >
> >Paul
> >
> >----- Original Message -----
> >From: "Kevin Horton" <khorton01@rogers.com>
> >To: <aeroelectric-list@matronics.com>
> >Subject: Re: AeroElectric-List: Re: Load dump comments
> >
> >
> > > --> AeroElectric-List message posted by: Kevin Horton
> ><khorton01@rogers.com>
> > >
> > > I'm interested as to which two items the crowbar was shorting when
> > > these large currents were measured. I'm assuming this is a different
> > > application than the crowbar OV protection that Bod espouses, where
> > > the crowbar shorts out the field circuit, popping a 5A CB. I can't
> > > imagine how 400 to 700 amps could be generated in the field circuit
> > > before the 5A CB popped. Are CBs that slow to trip? Or, was this a
> > > different application of a crowbar?
> > >
> > > Kevin Horton
> > >
> > > >--> AeroElectric-List message posted by: "Paul Messinger"
> ><paulm@olypen.com>
> > > >
> > > >The huge current loop during a shorting crowbar event generates a
large
> > > >magnetic field that can magnetize steel and mess up your compass
> > > >calibration.
> > > >
> > > >I got 400 amps with longer that likely wires. When I simulated my
> >aircraft
> > > >wiring I got over 700 amps.
> > > >
> > > >Measurements were made with calibrated equipment. as well as being
> > > >repeatable.
> > > >
> > > >If this does not bother you, be my guest.
> > > >
> > > >Paul
> > > >
> > > >
> > > >> Sure that sounds scary but I'll wait for the report before getting
> > > >> concerned. With 6 feet of 18awg wire in series with a C/B, an SCR,
> >and
> > > >> several connections it may be possible to get a couple of hundred
> >amps
> > > >> of instantaneous current flowing but so what? It is drawing down
the
> > > >> voltage which is what we want.
> > > >>
> > > >> The interesting thing to me is a nuisance trip. It sounds like it
is
> > > >> possible to ramp up the alternator output during the delay (40
ms?)
> > > >> waiting for the OV contactor to open. However I haven't seen any
> >reason
> > > > > to be concerned about that yet and I will await the report.
> > >
> > >
> >
> >
>
>
Message 18
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| Subject: | Pilot stick grip priority options rev B |
--> AeroElectric-List message posted by: "Mark Banus" <mbanus@hotmail.com>
Bob,
I am about to start building your circuit for pilot priority. I intend to
use 1N4001 diodes and a T9AP5D52-12 relay. Is there a more appropriate relay
for this application?
Thanks
Mark Banus
Glasair S II S FT
Message 19
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| Subject: | Re: Load Dump Question |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
As I recall the original start of this thread was early last year when there
were failures of Van's rebuilt alternators. Bob and others questioned the
quality of the rebuilt regulator in the Van's alternator.
Personally I have never seen any real proof of what was the true cause. I
have real trouble believing Van would sell substandard alternators. ALL
standard alternator internal regulators are protected against worst case
load dump.
Any way You are correct that in the case of a real alternator regulator HI
voltage failure, the only solution is to cut the "B" lead and "so what" if
that causes an isolated load dump that the alternator cannot take.
However if the alternator is working fine and the battery is disconnected
the resulting load dump is distributed to the bus and can cause harm
depending on what is on the bus and how big the load dump is.
There are a couple of solutions to this. First a transorb big enough to
clamp the load dump hi voltage. This has nothing directly to do with any OVP
device present.
However Bob's crow bar OVP will trigger with the above load dump and this
results in the hi current during its operation that some of us object to. A
simple addition of a small value series resistor fixes that.
If the load dump is a result of the "B" lead opening the load dump issue is
contained to the alternator where you may or may not damage the alternator
internal regulator. A transorb on the alternator side of the "B" lead
contactor will protect the alternator if the regulator is not up to the
task. This is a second transorb as one needs to be on the Bus side also.
If the load dump is a result of disconnecting a charging battery the load
dump is delivered to the aircraft bus and potential damage can result to
your avionics. Its likely the OVP will trip but not in time in all cases to
prevent a short hi voltage pulse on the BUS. The OVP takes some time to
start clamping (5-10MS?) and much longer (50-100ms) to disconnect the
alternator thru the "B" lead contactor. Even 5 ms is long with a 60V or
higher pulse on BUS.
So some of us feel the need for the "Transorb" to keep the BUS voltages
clamped while the OVP can act. The transorb acts not in 5 MS but in 1/2 pico
second 10,000+ times faster and faster than any damage can start.
If the failure is a failed hi voltage alternator the transorb clamps the
voltage while the OVP acts. Both arte needed in the safest system.
If this does not answer your concerns ask more as everyone benefits from
such a "conversation"
Paul
----- Original Message -----
From: "Vincent Welch" <welchvincent@hotmail.com>
Subject: AeroElectric-List: Load Dump Question
> --> AeroElectric-List message posted by: "Vincent Welch"
<welchvincent@hotmail.com>
>
> Hey guys, I have been watching this "Battle Of The Titans" with great
> interest. I have a question from one a bit lower down the food chain:)
>
> It has always been my understanding that the purpose of the OV circuit was
> to protect my avionics from a runaway alternator. The alternator or
> regulator has already failed and the voltage is climbing. The crowbar
opens
> the circuit to limit prevent damage to my expensive avionics. The
> alternator/regulator has already failed, its trash, so I open the B-lead
> under load, I get a load dump event. So what? Why do I care about trying
> to protect the alternator now?
>
> I can understand limiting the crowbar circuit current and adding a
resistor
> sounds like a simple easy solution to that problem.
>
> What am I missing here? Please further educate me.
>
> Vince
>
>
Message 20
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| Subject: | Re: turning off an internally regulated alternator |
--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
Thanks I will try to get more info monday when they are open.
Paul
----- Original Message -----
From: "Alex Peterson" <alexpeterson@earthlink.net>
Subject: RE: AeroElectric-List: turning off an internally regulated
alternator
> --> AeroElectric-List message posted by: "Alex Peterson"
<alexpeterson@earthlink.net>
>
>
> Mine is (was) new five years ago. Call to confirm, but I seem to recall
> that Aerosport Power got them from Niagara Air Parts. See
> http://www.niagaraairparts.com/ 3/4's down the page.
>
> Alex Peterson
>
> > --> AeroElectric-List message posted by: "Paul Messinger"
> > --> <paulm@olypen.com>
> >
> > Thanks that clears that up. I wonder is your a rebuilt unit
> > or OEM original as the internal regulators might be wired
> > differently. ALL my investigations were on alternators off
> > autos and none from rebuilders.
> >
> > Paul
> >
> > ----- Original Message -----
> > From: "Alex Peterson" <alexpeterson@earthlink.net>
> > To: <aeroelectric-list@matronics.com>
> > Subject: RE: AeroElectric-List: turning off an internally
> > regulated alternator
> >
> >
> > > --> AeroElectric-List message posted by: "Alex Peterson"
> > <alexpeterson@earthlink.net>
> > >
> > > > ALL the Jap internally regulated alternators INCL ND (that I have
> > > > looked at and that is quite a few but no where all types and ND
> > > > alone has several different designs) cannot be turned off once
> > > > turned on and running.
> > > >
> > > > Toggle the alt ON OFF connection all you want but the internal
> > > > regulator is LATCHED on.
> > > >
> > > > IS vans ND different??
> > >
> > > Paul,
> > >
> > > I have an internally regulated ND 40amp alternator (Niagara
> > Air Parts)
> > which
> > > came with my Aerosport engine. The above statement is not
> > true in my
> > case.
> > > My master switch is a three position setup, when the engine
> > is running
> > > and
> > I
> > > turn off the alternator (which disconnects the 5 amp supply to the
> > > alternator), the bus voltage drops to battery voltage.
> > Turn it on, 14
> > > volts, off 12, etc..
> > >
> > > Alex Peterson
> > > RV6-A 569 hours
> > > Maple Grove, MN
> > >
> > > http://www.home.earthlink.net/~alexpeterson/
> > >
> > >
> >
> >
> > =========
> > Matronics Forums.
> > =========
> > http://www.matronics.com/FAQ/AeroElectric-List.htm
> > =========
> >
> >
> >
> >
> >
>
>
Message 21
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| Subject: | Garmin/Microencoder wiring question |
--> AeroElectric-List message posted by: "Dan O'Brien" <danobrien@cox.net>
I am wiring the serial connection from my Microencoder to my Garmin
430. The Garmin documentation shows a shielded twisted pair with the
shield grounded a both ends and the Attitude Common pin (part of the
twisted pair) connected to the shield at the Garmin and connected to the
Power Ground wire at the encoder. Question: Does it matter whether the
Attitude Common pin is grounded at the Garmin given that it is also
grounded through the encoder? I'm asking because I already wired the
Garmin end without connecting it to the shield. I can always rip the pin
out and do it over, but would prefer not to :).
Message 22
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| Subject: | General radio grounding question |
--> AeroElectric-List message posted by: "Dan O'Brien" <danobrien@cox.net>
My Garmin 430 and UPS SL30 both have case ground studs. Question: Do the
ground studs run to Power Ground through the radios, or are they something
completely different?
I'm puzzling over this because my Garmin came with a partial harness that
connects shields to the case, which is simply depicted with a ground symbol
in the installation manual. I'm assuming that this means that the case is
connected to the Aircraft ground through the Power Ground pin in the
harness. If this were not the case, how would I know from the ground
symbol depicted in the manual that the case ground is something different
than the aircraft power ground? There is no mention in the manual that the
shields should be grounded to the case INSTEAD OF the aircraft power ground.
If I sound a bit confused, it's because I AM !
Message 23
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|
| Subject: | Re: Garmin/Microencoder wiring question |
--> AeroElectric-List message posted by: "Wayne Sweet" <w_sweet@comcast.net>
I just finished wiring my 430 with encoder, but the input was the 11 pin
(gray code, I think it's referred to as). The Garmin wiring diagrams are
wrong in this and one other in respect to the grounding at both ends of the
shields. Do not ground both ends of the shields or the least that will
(could) cause a ground plane loop. I called, and asked Garmin tech guys at
the AOPA convention about the shield grounding at both ends for the GI-106A
obs, and at first I received somewhat blank stares. Then finally got a
definitive NO, do not ground shields at both ends. I know for a fact, that
grounding the shields between the 430 and the audio panel (in my case, PS
Engineering's PMA6000) will cause havoc with the com output.
On mine the altitude common is simply ground. This was the answer I finally
got from Garmin; the TransCal (my encoder) people didn't know and in fact
ask me to call them back when I found the answer. If the encoder pin-out has
a Altitude Common, then of course use it.
BTW, I would NEVER do that sort of wiring job myself (GNS430, GI-106A,
PMA6000, Navaid Device, Terra NAV/COM, Terra Marker Beacon). After having
done it, I learned of FastStack by Approach Systems.
Good luck; Oh I learned that the ungrounded end of the shields should be
heat shrink wrapped to prevent the shield from touching any structure, other
wires, thereby causing a ground plane loop.
Wayne
----- Original Message -----
From: "Dan O'Brien" <danobrien@cox.net>
Subject: AeroElectric-List: Garmin/Microencoder wiring question
> --> AeroElectric-List message posted by: "Dan O'Brien" <danobrien@cox.net>
>
> I am wiring the serial connection from my Microencoder to my Garmin
> 430. The Garmin documentation shows a shielded twisted pair with the
> shield grounded a both ends and the Attitude Common pin (part of the
> twisted pair) connected to the shield at the Garmin and connected to the
> Power Ground wire at the encoder. Question: Does it matter whether the
> Attitude Common pin is grounded at the Garmin given that it is also
> grounded through the encoder? I'm asking because I already wired the
> Garmin end without connecting it to the shield. I can always rip the pin
> out and do it over, but would prefer not to :).
>
>
>
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Message 24
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| Subject: | Re: General radio grounding question |
--> AeroElectric-List message posted by: "Wayne Sweet" <w_sweet@comcast.net>
The assumption is (by Garmin) is the 430 tray is connected to the airframe
through mounting screws, and the ground terminals (I found the purpose of
those at AOPA convention) is connected to the tray, and the tray to the
airframe. At least that's the way mine is and it works.
Wayne
----- Original Message -----
From: "Dan O'Brien" <danobrien@cox.net>
Subject: AeroElectric-List: General radio grounding question
> --> AeroElectric-List message posted by: "Dan O'Brien" <danobrien@cox.net>
>
> My Garmin 430 and UPS SL30 both have case ground studs. Question: Do the
> ground studs run to Power Ground through the radios, or are they something
> completely different?
>
> I'm puzzling over this because my Garmin came with a partial harness that
> connects shields to the case, which is simply depicted with a ground
> symbol
> in the installation manual. I'm assuming that this means that the case is
> connected to the Aircraft ground through the Power Ground pin in the
> harness. If this were not the case, how would I know from the ground
> symbol depicted in the manual that the case ground is something different
> than the aircraft power ground? There is no mention in the manual that
> the
> shields should be grounded to the case INSTEAD OF the aircraft power
> ground.
>
> If I sound a bit confused, it's because I AM !
>
>
>
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Message 25
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|
| Subject: | Re: Load Dump Question |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 02:26 PM 1/22/2005 -0800, you wrote:
>--> AeroElectric-List message posted by: "Paul Messinger" <paulm@olypen.com>
>
>As I recall the original start of this thread was early last year when there
>were failures of Van's rebuilt alternators. Bob and others questioned the
>quality of the rebuilt regulator in the Van's alternator.
>
>Personally I have never seen any real proof of what was the true cause. I
>have real trouble believing Van would sell substandard alternators. ALL
>standard alternator internal regulators are protected against worst case
>load dump.
>
>Any way You are correct that in the case of a real alternator regulator HI
>voltage failure, the only solution is to cut the "B" lead and "so what" if
>that causes an isolated load dump that the alternator cannot take.
>
>However if the alternator is working fine and the battery is disconnected
>the resulting load dump is distributed to the bus and can cause harm
>depending on what is on the bus and how big the load dump is.
>
>There are a couple of solutions to this. First a transorb big enough to
>clamp the load dump hi voltage. This has nothing directly to do with any OVP
>device present.
>
>However Bob's crow bar OVP will trigger with the above load dump and this
>results in the hi current during its operation that some of us object to. A
>simple addition of a small value series resistor fixes that.
If the battery is off line and the crowbar "trips" there is no
high current pulse. The alternator is physically incapable of
delivering more than a few percent above rated current. Once
the battery is out of the loop, a crowbar trip sinks the relatively
low current of the alternator . . . the alternator looses excitation
and dies.
>If the load dump is a result of the "B" lead opening the load dump issue is
>contained to the alternator where you may or may not damage the alternator
>internal regulator. A transorb on the alternator side of the "B" lead
>contactor will protect the alternator if the regulator is not up to the
>task. This is a second transorb as one needs to be on the Bus side also.
Why? if load dump energies come from the alternator, one Transorb
at the alternator's b-lead terminal should suffice for all cases.
>If the load dump is a result of disconnecting a charging battery the load
>dump is delivered to the aircraft bus and potential damage can result to
>your avionics. Its likely the OVP will trip but not in time in all cases to
>prevent a short hi voltage pulse on the BUS. The OVP takes some time to
>start clamping (5-10MS?) and much longer (50-100ms) to disconnect the
>alternator thru the "B" lead contactor. Even 5 ms is long with a 60V or
>higher pulse on BUS.
>
>So some of us feel the need for the "Transorb" to keep the BUS voltages
>clamped while the OVP can act. The transorb acts not in 5 MS but in 1/2 pico
>second 10,000+ times faster and faster than any damage can start.
>
>If the failure is a failed hi voltage alternator the transorb clamps the
>voltage while the OVP acts. Both arte needed in the safest system.
>
>If this does not answer your concerns ask more as everyone benefits from
>such a "conversation"
Agreed!
Bob . . .
Message 26
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| Subject: | Re: Load Dump Question |
--> AeroElectric-List message posted by: "Vincent Welch" <welchvincent@hotmail.com>
OK, I'm almost with you Paul. If I place a transorb (say, the Whackjack) on
the alternator side of the B-Lead contactor, doesn't that clamp the entire
line from alternator, through contactor, to the bus? If the battery is
taken offline accidently isn't the bus still clamped through that transorb?
If the B-Lead contactor opens due to the OVP trip won't the bus voltage be
stabilized by the battery? If all of these things are true, why do we need
a second transorb on the bus side?
If I do need a second transorb on the bus side, is another Whackjack
acceptable or should I use something else? If so, what?
Vince
>From: "Paul Messinger" <paulm@olypen.com>
>Reply-To: aeroelectric-list@matronics.com
>To: <aeroelectric-list@matronics.com>
>Subject: Re: AeroElectric-List: Load Dump Question
>Date: Sat, 22 Jan 2005 14:26:53 -0800
>
>--> AeroElectric-List message posted by: "Paul Messinger"
><paulm@olypen.com>
>
>As I recall the original start of this thread was early last year when
>there
>were failures of Van's rebuilt alternators. Bob and others questioned the
>quality of the rebuilt regulator in the Van's alternator.
>
>Personally I have never seen any real proof of what was the true cause. I
>have real trouble believing Van would sell substandard alternators. ALL
>standard alternator internal regulators are protected against worst case
>load dump.
>
>Any way You are correct that in the case of a real alternator regulator HI
>voltage failure, the only solution is to cut the "B" lead and "so what" if
>that causes an isolated load dump that the alternator cannot take.
>
>However if the alternator is working fine and the battery is disconnected
>the resulting load dump is distributed to the bus and can cause harm
>depending on what is on the bus and how big the load dump is.
>
>There are a couple of solutions to this. First a transorb big enough to
>clamp the load dump hi voltage. This has nothing directly to do with any
>OVP
>device present.
>
>However Bob's crow bar OVP will trigger with the above load dump and this
>results in the hi current during its operation that some of us object to. A
>simple addition of a small value series resistor fixes that.
>
>If the load dump is a result of the "B" lead opening the load dump issue is
>contained to the alternator where you may or may not damage the alternator
>internal regulator. A transorb on the alternator side of the "B" lead
>contactor will protect the alternator if the regulator is not up to the
>task. This is a second transorb as one needs to be on the Bus side also.
>
>If the load dump is a result of disconnecting a charging battery the load
>dump is delivered to the aircraft bus and potential damage can result to
>your avionics. Its likely the OVP will trip but not in time in all cases to
>prevent a short hi voltage pulse on the BUS. The OVP takes some time to
>start clamping (5-10MS?) and much longer (50-100ms) to disconnect the
>alternator thru the "B" lead contactor. Even 5 ms is long with a 60V or
>higher pulse on BUS.
>
>So some of us feel the need for the "Transorb" to keep the BUS voltages
>clamped while the OVP can act. The transorb acts not in 5 MS but in 1/2
>pico
>second 10,000+ times faster and faster than any damage can start.
>
>If the failure is a failed hi voltage alternator the transorb clamps the
>voltage while the OVP acts. Both arte needed in the safest system.
>
>If this does not answer your concerns ask more as everyone benefits from
>such a "conversation"
>
>Paul
>
>----- Original Message -----
>From: "Vincent Welch" <welchvincent@hotmail.com>
>To: <aeroelectric-list@matronics.com>
>Subject: AeroElectric-List: Load Dump Question
>
>
> > --> AeroElectric-List message posted by: "Vincent Welch"
><welchvincent@hotmail.com>
> >
> > Hey guys, I have been watching this "Battle Of The Titans" with great
> > interest. I have a question from one a bit lower down the food chain:)
> >
> > It has always been my understanding that the purpose of the OV circuit
>was
> > to protect my avionics from a runaway alternator. The alternator or
> > regulator has already failed and the voltage is climbing. The crowbar
>opens
> > the circuit to limit prevent damage to my expensive avionics. The
> > alternator/regulator has already failed, its trash, so I open the B-lead
> > under load, I get a load dump event. So what? Why do I care about
>trying
> > to protect the alternator now?
> >
> > I can understand limiting the crowbar circuit current and adding a
>resistor
> > sounds like a simple easy solution to that problem.
> >
> > What am I missing here? Please further educate me.
> >
> > Vince
> >
> >
>
>
Message 27
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| Subject: | Re: Garmin/Microencoder wiring question |
--> AeroElectric-List message posted by: "Dan O'Brien" <danobrien@cox.net>
>The Garmin wiring diagrams are wrong in this and one other in respect
>to the grounding at both ends of the
>shields. Do not ground both ends of the shields or the least that will
>(could) cause a ground plane loop. I called, and asked Garmin tech guys at
>the AOPA convention about the shield grounding at both ends for the GI-106A
>obs, and at first I received somewhat blank stares. Then finally got a
>definitive NO, do not ground shields at both ends.
So the manual is incorrect? Well, that leaves me in a lurch, since if the
shield
is only supposed to be grounded at one end, which end? Guess I'll call Garmin.
In the past, they've not been very helpful, as the unit is "supposed to be
wired by an avionics supplier." (This is unlike the old UPS, which was great
in supporting the experimental market. Of course, USP is now Garmin too.)
We'll see.
Message 28
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| Subject: | Re: General Wiring Question |
--> AeroElectric-List message posted by: "Dan O'Brien" <danobrien@cox.net>
>The assumption is (by Garmin) is the 430 tray is connected to the airframe
>through mounting screws, and the ground terminals (I found the purpose of
>those at AOPA convention) is connected to the tray, and the tray to the
>airframe. At least that's the way mine is and it works.
On a composite like my Lancair, the mounting screws will not ground the tray.
Is one supposed to run a wire from the ground stud
on the radio case to the ground bus? There is no mention of this
in either the Garmin 430 or UPS SL30 manuals.
Message 29
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| Subject: | Re: Garmin/Microencoder wiring question |
--> AeroElectric-List message posted by: "Wayne Sweet" <w_sweet@comcast.net>
Dan,
I told them it was an experimental airplane and I was the builder. They
willingly answered my questions. Are you calling Garmin or the avionics
retail store you bought it from??
I would ground the shields for the encoder wiring at the GND430, on the
shield ground connector.
Wayne
----- Original Message -----
From: "Dan O'Brien" <danobrien@cox.net>
Subject: AeroElectric-List: Re: Garmin/Microencoder wiring question
> --> AeroElectric-List message posted by: "Dan O'Brien" <danobrien@cox.net>
>
>
> >The Garmin wiring diagrams are wrong in this and one other in respect
> >to the grounding at both ends of the
> >shields. Do not ground both ends of the shields or the least that will
> >(could) cause a ground plane loop. I called, and asked Garmin tech guys
> >at
> >the AOPA convention about the shield grounding at both ends for the
> >GI-106A
> >obs, and at first I received somewhat blank stares. Then finally got a
> >definitive NO, do not ground shields at both ends.
>
> So the manual is incorrect? Well, that leaves me in a lurch, since if the
> shield
> is only supposed to be grounded at one end, which end? Guess I'll call
> Garmin.
> In the past, they've not been very helpful, as the unit is "supposed to be
> wired by an avionics supplier." (This is unlike the old UPS, which was
> great
> in supporting the experimental market. Of course, USP is now Garmin too.)
> We'll see.
>
>
>
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Message 30
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| Subject: | Re: General Wiring Question |
--> AeroElectric-List message posted by: "Wayne Sweet" <w_sweet@comcast.net>
OK, I may be wrong. The 430 does have a ground wire for both the COM and GPS
power supplies (connectors P4002 and P4001). Check with a multimeter (ohms)
to see if the ground terminals, that funny looking thing on the back of the
tray, Fig F-6 which identifies it as Shield Grounds, and one of the ground
wires have continuity when the 430 is plugged in. If not, then I would guess
you need to run a ground wire from the tray to you aircraft ground bus.
Let us know what you find out.
Wayne
----- Original Message -----
From: "Dan O'Brien" <danobrien@cox.net>
Subject: AeroElectric-List: Re: General Wiring Question
> --> AeroElectric-List message posted by: "Dan O'Brien" <danobrien@cox.net>
>
>
> >The assumption is (by Garmin) is the 430 tray is connected to the
> >airframe
> >through mounting screws, and the ground terminals (I found the purpose of
> >those at AOPA convention) is connected to the tray, and the tray to the
> >airframe. At least that's the way mine is and it works.
>
> On a composite like my Lancair, the mounting screws will not ground the
> tray.
> Is one supposed to run a wire from the ground stud
> on the radio case to the ground bus? There is no mention of this
> in either the Garmin 430 or UPS SL30 manuals.
>
>
>
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