Today's Message Index:
----------------------
1. 08:27 AM - Re: - aircraft wiring (Eric M. Jones)
2. 09:02 AM - Toggle Switch for Starter (Phil Birkelbach)
3. 09:12 AM - Re: Dumb Questions (Robert L. Nuckolls, III)
4. 09:21 AM - Protecting LEDs (PeterHunt1@aol.com)
5. 09:51 AM - Re: LED Panel Lights (LarryRobertHelming)
6. 05:19 PM - Re: Another One.. (lm4@juno.com)
7. 06:13 PM - Re: Protecting LEDs (Mike Heinen)
8. 06:27 PM - Re: Re: - aircraft wiring (Robert L. Nuckolls, III)
9. 06:29 PM - Re: aircraft wiring (Robert L. Nuckolls, III)
10. 08:44 PM - Altitude encoder recommendation? (richard@riley.net)
11. 09:22 PM - Re: Toggle Switch for Starter (Robert L. Nuckolls, III)
12. 09:29 PM - Re: Protecting LEDs (Robert L. Nuckolls, III)
13. 09:41 PM - Re: Another One.. (Robert L. Nuckolls, III)
14. 10:34 PM - Re: Altitude encoder recommendation? (Dan Checkoway)
15. 10:38 PM - Re: Protecting LEDs (John R)
16. 11:54 PM - Re: Hall sensor problem??? (Larry & Gerry)
Message 1
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| Subject: | Re: - aircraft wiring |
--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
> 28. 11:16 PM - aircraft wiring (TimRhod@aol.com)
> I was reading http://www.expbus.com/pdfs/wiresize.PDF In this document
> it states that AC43.13 gives a maximum allowable voltage drop of of 0.5
> volts in a wire circuit. It gives an example of an 18 AWG wire and says
the
> maximum allowable length is 9.25 feet.
And doubtlessly some mysterious problems occur as a result. I once had a
small
job to lower a video camera and 12V lights several hundred feet down a hole.
The lights were 8A.
The end result was achieved only by using a 24 volt power supply on top and
a 12V regulator
at the camera end.
> Yet in almost every aircraft wiring diagram I see nav lights wired with
18AWG
> and the circuit has to be 30 to 40 feet. Can you explain this?
In the near future running a bunch of wires to a remote point will seem
barbaric. There are a variety of systems today for running ONE wire out to
multiple loads. The complexity is not great. Even slicker is a high voltage
3-phase AC power to remote loads. Those military guys and their 400 Hz
devices...they're not crazy. All this is easier and cheaper than it has ever
been. We live in a land of undreamt-of riches.
>...building a velocity and almost every circuit that goes to the rear is
15ft
> one way. 30ft round trip. Certainly I don't have to use huge wires for
all
> these circuits Please Help?
Stay tuned. Soon!
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
Phone (508) 764-2072
Email: emjones@charter.net
Ring the bells that still can ring
Forget your perfect offering
There is a crack in everything
That's how the light gets in
- - Leonard Cohen
Message 2
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| Subject: | Toggle Switch for Starter |
--> AeroElectric-List message posted by: "Phil Birkelbach" <phil@petrasoft.net>
I was looking on B and C's website this weekend trying to get all my
switches ordered and I can't find the S700-1-8 switch. (SPDT with spring
return) Can I still order it from them or do I need to find another source?
If I find another source what do I need to order to make sure that it looks
the same as the others?
Godspeed,
Phil Birkelbach
RV-7 Houston
Message 3
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| Subject: | Re: Dumb Questions |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 06:59 AM 9/1/2003 +0200, you wrote:
>--> AeroElectric-List message posted by: "Werner Schneider"
><wernerschneider@compuserve.com>
>
> > 1) Grounding: Even though Iam buildingan aircraft with a steel tube
>fuselage I am planning on running a separate ground cable from instrument
>panel ground bus directly to the battery.
>
> correct
>
> > 2) The alternatorFIELDbreakergoeson the panel and the alternatorOUTPUT
>cirquit protection (probably fusible link in my case)goes near the starter
>contactor, correct?
>
>fuselink for 40 Amps, I doubt, the fuse goes as close a spossible to the
>alternator, which might in this case be on the firewall close to the
>starter contactor.
"Fuselink" should not be confused with "fusible link" and
the supper fat fuses like the JJN/JJS/ANL series fuses
that you will find called out on various wiring diagrams.
Fusible links are described at:
http://www.aeroelectric.com/articles/fuselink/fuselink.html
really big fuses (sometimes called current limiters)
are illustrated at:
http://www.aeroelectric.com/articles/fuselink/fuselink.html
http://216.55.140.222/Pictures/clbase.jpg
and
http://www.bussmann.com/library/bifs/1029.pdf
Circuit protection goes as close as possible to the
SOURCE of energy that puts the wire at risk. Alternators
are physically incapable of tripping their own b-lead
protection . . . it's ship's BATTERY that will burn
this wire IF you experience mechanical failure or shorted
diodes in alternator (both very rare). Sooo . . . b-lead
protection is installed at the FAR END of the wire
leading from alternator b-lead to wherever it ties to
ship's power distribution.
> >
> > 3) When would one want to pull the alternator field breaker to run on
>battery only?
>
>if you want to shutdown the alternator you pull the breaker, this could be
>for test reason, or if you supsect the OV did not work or ..... and the
>breaker is also triggered from the OV module.
OR . . . should the regulator become unstable and
the bus voltage is jumping round (like the thread on
increased alternator field supply resistance we've
been discussing in another thread). The breaker is
shown on our wiring diagrams as the ONLY breaker in
a fuse-block equipped airplane because the CROWBAR
OV protection needs the breaker. It's not included
just because you "might want to pull the field
breaker" . . . the latest versions of Z-drawings
show the S700-2-10 progressive transfer switch that
mimics the infamous split-rocker switch and allows
you to move the DC PWR MASTER switch to a mid, battery
only operating position.
Bob . . .
Message 4
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--> AeroElectric-List message posted by: PeterHunt1@aol.com
Hi Bob,
I would appreciate your helping me better understanding when and how to
protect LED lights. I read your recent post where you suggest putting a 330 ohm
resister in series at the feed end to the LED and a diode (1N4005 or similar) in
parallel with the LED with banded end (cathode) of the diode tied to the plus
wire on the LED. My first question ... Should I wire each of the following
four LEDs on my panel in this manner?
1. LED in parallel with flap motor when switch is in the "flaps up" position.
2. LED in parallel with pitot heat.
3. LED in series with micro switch on canopy locking mechanism.
4. LED in parallel with boost pump.
I am using Radio Shack 276-084A LEDs. Both wires are equal length. My
second question ... Is the red wire of the LED positive and the black wire
negative? (This is a convenient LED as the bulb has a lip on the outside and a
nut
on the back side and so requires no holder.) Just a 13/64" hole in the panel.
Thanks in advance, Bob.
Peter
Message 5
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| Subject: | Re: LED Panel Lights |
--> AeroElectric-List message posted by: "LarryRobertHelming" <lhelming@sigecom.net>
Jon: I have a couple of these Jameco #150922 clusters and have tested them.
They will work just great for what you are wanting to do with them. I have
even tested with a zener diode in line to reduce their brightness which
seems more than adequate for night use. The current draw is low and with
the expected long life of the led I am considering not putting them on a
switch but rather just leaving them on at all times the main is on. I plan
to wire one light to main buss and other to e-buss each with 1 amp fuse.
Indiana Larry, RV7 Tip-up TMX-O-360 ACS2002 Dynon CNS430 Digitrak
On Finish Kit
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
Subject: Re: AeroElectric-List: LED Panel Lights
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<bob.nuckolls@cox.net>
>
> At 05:05 PM 8/31/2003 -0500, you wrote:
> >--> AeroElectric-List message posted by: "Jon Finley" <jon@finleyweb.net>
> >
> >Hi all,
> >
> >I'm working on a panel lighting project and am looking for some input.
> >
> >I fly a Q2 which, for a seatback, has a full height bulkhead and full
> >canopy. I would like to install two LED clusters in this seatback
> >bulkhead that shine on the panel. I don't have individually lighted
> >gauges and don't plan to install post lights. So, with that in mind:
> >
> >I have searched for LED clusters I have found these units
> >(http://www.jameco.com/cgi-bin/ncommerce3/ProductDisplay?prmenbr=91&prrf
> >nbr=4151&cgrfnbr=501&ctgys=) from Jameco (Jameco #150922). They don't
> >provide any beam width information, of course.
> >
> >I don't mind fabricating my own mount and/or my own LED cluster.
> >Wondering if anyone has already done this and has tips that could save
> >the next person (me!) some time??
>
> Sure . . . and it's easy. For an overhead flood, you probably
> don't want someone else's idea of what a "cluster" of
> LEDs is supposed to do. When you get one of the prefab
> assy leds pointed the right way, you'll be lucky if more
> than one of the remaining LEDs points where you want it.
>
> I've built LED replacements for the overhead flood
> in high wing ships like a Cessna using at most 4 and usually
> only 3, hi-intensity red LEDs. Three lamps in series can
> be powered from 12v with a 180 ohm resistor to limit current.
>
> Just jury-rig a means for holding the lamps and positioning
> them for best uniformity across the panel. Once you've decided
> how many lamps and where they need to point, you can work
> on hardening up the mounting for permanent installation.
>
> Some builders have designed overhead floods to run from
> an array of 9v alkaline batteries. For no more often than
> you'll need panel lighting, three alkaline batteries will
> give you approximately 30 hours of high intensity lighting
> and 50-60 low intensity lighting. This would make your
> panel lighting totally independent of ship's power.
>
> If you want to work with white lights, use only 2
> in series per 180 ohm resistor. Count on four lights
> total, two separate strings.
>
> Bob . . .
>
>
Message 6
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| Subject: | Re: Another One.. |
--> AeroElectric-List message posted by: lm4@juno.com
Grant,
Have a look at Z-11 again. The left mag has no power to it.
It's a mag and makes it's own power. The other diagram, the one
powered by the battery buss, goes to an electronic ignition.
Still nothing to do with the starter. The start switch shows as a
push button but could be anything. A twenty awg wire with a 7 amp
fuse could hang out of your panel and you could touch them together
to energize the starter solonoid. A standard size, spring loaded of
course,
would be quite acceptable for this kind of light current load. Most of
these small solonoids draw less than an amp. HTH.
Larry Mac Donald
Rochester N.Y.
--> AeroElectric-List message posted by: "Tinne maha"
<tinnemaha@hotmail.com>
Forgot one question I know it seems really dumb but I'd feel better
hearing the answer I'm 99% sure of.
I'm unclear about the starter switch on the panel: The way Z-11 is drawn
the starter is energized by a spring loaded toggle mag switch.That's
whatI'm planning on. I've been confused though bytalk ofpush button
starters. I know they are an option for those who like them but are they
a requirement ( the spring loaded toggle switch only allows current to
flow to the push button starter)?
Thanks again,
Grant
Message 7
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| Subject: | Re: Protecting LEDs |
--> AeroElectric-List message posted by: "Mike Heinen" <mjheinen@adelphia.net>
My understanding is the resistor is to get the voltage down to tolerable
levels for the LED. The long lead should be positive. THe LEDsI have are
rated at 3.6 volts at 20 mA. I used 47 ohm resitors ...one on each side of
the LEDs with the circuit being...
12 volt battery positive >switch > 47 ohm resistor > Positive lead on led>
Negative lead on led > + led >- led >+led > - led > 47 ohm resistor >
negative ground.
Check out ....good service and price...
http://www.whitelightled.com/
----- Original Message -----
From: <PeterHunt1@aol.com>
Subject: AeroElectric-List: Protecting LEDs
> --> AeroElectric-List message posted by: PeterHunt1@aol.com
>
> Hi Bob,
>
> I would appreciate your helping me better understanding when and how to
> protect LED lights. I read your recent post where you suggest putting a
330 ohm
> resister in series at the feed end to the LED and a diode (1N4005 or
similar) in
> parallel with the LED with banded end (cathode) of the diode tied to the
plus
> wire on the LED. My first question ... Should I wire each of the
following
> four LEDs on my panel in this manner?
>
> 1. LED in parallel with flap motor when switch is in the "flaps up"
position.
>
> 2. LED in parallel with pitot heat.
>
> 3. LED in series with micro switch on canopy locking mechanism.
>
> 4. LED in parallel with boost pump.
>
> I am using Radio Shack 276-084A LEDs. Both wires are equal length. My
> second question ... Is the red wire of the LED positive and the black
wire
> negative? (This is a convenient LED as the bulb has a lip on the outside
and a nut
> on the back side and so requires no holder.) Just a 13/64" hole in the
panel.
>
> Thanks in advance, Bob.
>
> Peter
>
>
Message 8
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| Subject: | Re: - aircraft wiring |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
Didn't see where this thread got started so I'm not really sure
of the details offered by the original posting . . .
At 11:31 AM 9/1/2003 -0400, you wrote:
>--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
>
> > 28. 11:16 PM - aircraft wiring (TimRhod@aol.com)
> > I was reading http://www.expbus.com/pdfs/wiresize.PDF In this document
> > it states that AC43.13 gives a maximum allowable voltage drop of of 0.5
> > volts in a wire circuit. It gives an example of an 18 AWG wire and says
>the
> > maximum allowable length is 9.25 feet.
>
>And doubtlessly some mysterious problems occur as a result. I once had a
>small
>job to lower a video camera and 12V lights several hundred feet down a hole.
>The lights were 8A.
>The end result was achieved only by using a 24 volt power supply on top and
>a 12V regulator
>at the camera end.
>
> > Yet in almost every aircraft wiring diagram I see nav lights wired with
>18AWG
> and the circuit has to be 30 to 40 feet. Can you explain this?
It's not difficult. Nav light circuits are unique in that unlike
ALL other systems in the airplane, the circuit branches out to
MULTIPLE loads. Each LOAD in a 14v nav light circuit is a 2A bulb
for a combined system load of 6A. While 18AWG wire is indeed
oversized for the load presented by each lamp, one has to consider
that the circuit protection and individual strands of wire should
match up. Sooo . . . if one puts 10A of circuit protection on
the nav lights, one is obligated to string wire of that rating
(or larger) also. Hence 18AWG.
Now, how about voltage drop. 18AWG is 6.4 milliohms per foot.
2A of current products 12.8 millivolts per foot drop. 500
millivolts divided 12.8 mv/foot yields 39 feet. In a composite
aircraft this means that your nav light can be 20 wire-feet
away from the source for a 40-foot round trip.
I suspect the 9.25 foot value cited came from the notion that
every strand of wire in the system carries total load for the
system which isn't true.
Now, does the breaker/fuse HAVE to be 10A? No, you're
only drawing 6A so a 7.5A protection would do. If you're
building a metal airplane and will ground nav lights
locally, one could consider 20AWG wire at 10 milliohms
per foot where a 25-foot loop length calculates under the
RECOMMENDED 500 millivolt drop per lamp circuit.
> >...building a velocity and almost every circuit that goes to the rear is
> 15ft
> > one way. 30ft round trip. Certainly I don't have to use huge wires for all
> > these circuits Please Help?
The 500 mv suggestion is just that, a suggestion. He's so
close to the 25-foot loop limit for 20AWG wire that should
he be inclined to run the 20 instead of 18, it's no big deal.
If he has other system that requires 18AWG wire, then ordering
enough to do that system along with the nav lights would make
sense but if nav lights is the ONLY system that calls for
18, then wiring it with 20 and fusing it at 7.5 amps would be
an acceptable alternative.
Bob . . .
Message 9
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| Subject: | Re: aircraft wiring |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 02:15 AM 9/1/2003 -0400, you wrote:
>--> AeroElectric-List message posted by: TimRhod@aol.com
oops, okay, the original post showed up in my mailbox . . .
>Can someone tell me if M22759/16 aircraft wire is the same as Mil-W-22759/16
>aircraft wire? I found the former on the web at a significanty less cost
>than the latter.
Yes, they are the same wire.
>Also I was reading http://www.expbus.com/pdfs/wiresize.PDF In this document
>it states that AC43.13 gives a maximum allowable voltage drop of of 0.5
>volts in a wire circuit. It gives an example of an 18 AWG wire and says the
>maximum allowable length is 9.25 feet.
see my post of a few minutes ago . . .
>Yet in almost every aircraft wiring diagram I see nav lights wired with 18AWG
>and the circuit has to be 30 to 40 feet. Can you explain this?
>
>Im building a velocity and almost every circuit that goes to the rear is 15ft
>one way. 30ft round trip. Certainly I dont have to use hugh wires for all
>these circiuts Please Help?
20AWG would probably be fine, 18AWG would definitely satisfy
the most discriminating critics.
Bob . . .
Message 10
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| Subject: | Altitude encoder recommendation? |
--> AeroElectric-List message posted by: richard@riley.net
I have a new Microair transponder I'm installing. I have an ancient Terra
encoder but I don't trust it, and I think I'm just going to chuck it and
buy a new one.
What do you all recommend? Transcal? Ack?
Message 11
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| Subject: | Re: Toggle Switch for Starter |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 11:23 AM 9/1/2003 -0500, you wrote:
>--> AeroElectric-List message posted by: "Phil Birkelbach"
><phil@petrasoft.net>
>
>I was looking on B and C's website this weekend trying to get all my
>switches ordered and I can't find the S700-1-8 switch. (SPDT with spring
>return) Can I still order it from them or do I need to find another source?
>If I find another source what do I need to order to make sure that it looks
>the same as the others?
>
>Godspeed,
>
>Phil Birkelbach
>RV-7 Houston
That one has never been stocked. You are about third person
in 5 or 6 years that wanted on. Most folks who have controlled
starters with toggles have interlocked them with magnetos such
that right mag has to be off and left mag on for starter to
be engaged by lifting left mag switch to full up. This uses
the 2-5 switch which is stocked by B&C. Alternatively
folks have used the guarded push-button also offered by
B&C. I'll drop them a note and see if they would add the 1-8 . . .
Bob . . .
Message 12
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| Subject: | Re: Protecting LEDs |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 12:20 PM 9/1/2003 -0400, you wrote:
>--> AeroElectric-List message posted by: PeterHunt1@aol.com
>
>Hi Bob,
>
>I would appreciate your helping me better understanding when and how to
>protect LED lights. I read your recent post where you suggest putting a
>330 ohm
>resister in series at the feed end to the LED and a diode (1N4005 or
>similar) in
>parallel with the LED with banded end (cathode) of the diode tied to the plus
>wire on the LED. My first question ... Should I wire each of the following
>four LEDs on my panel in this manner?
when they're used as a starter engaged light, there is some
risk to the led for low energy, reverse transients.
>1. LED in parallel with flap motor when switch is in the "flaps up" position.
>
>2. LED in parallel with pitot heat.
>
>3. LED in series with micro switch on canopy locking mechanism.
>
>4. LED in parallel with boost pump.
>
>I am using Radio Shack 276-084A LEDs. Both wires are equal length. My
>second question ... Is the red wire of the LED positive and the black wire
>negative? (This is a convenient LED as the bulb has a lip on the outside
>and a nut
>on the back side and so requires no holder.) Just a 13/64" hole in the panel.
understand. I think your risks are minimal. it would be interesting
to see how they stand up in the service you've assigned to them
without going to any extra lengths to "protect" them.
Bob . . .
Message 13
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| Subject: | Re: Another One.. |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 06:49 PM 8/31/2003 -0700, you wrote:
>--> AeroElectric-List message posted by: "Tinne maha" <tinnemaha@hotmail.com>
>
>Forgot one question I know it seems really dumb but I'd feel better
>hearing the answer I'm 99% sure of.
>
>I'm unclear about the starter switch on the panel: The way Z-11 is drawn
>the starter is energized by a spring loaded toggle mag switch.That's
>whatI'm planning on. I've been confused though bytalk ofpush button
>starters. I know they are an option for those who like them but are they a
>requirement ( the spring loaded toggle switch only allows current to flow
>to the push button starter)?
you can use either toggle or push-button switches for engagine
the starter. See figures Z-27, Z-28 and Z-12 for variations on
this theme. If you're going to interlock mags and starter such
that the starter cannot be engaged with non-impulse coupled
mag on, then you can use either Z-27 with two 2-3 switches for
mags and a S895-1 guarded push-button -OR- you can use
2-5 switches for the mags and wire so that starter is engaged
when left mag switch is pushed full up.
Bob . . .
Message 14
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| Subject: | Re: Altitude encoder recommendation? |
--> AeroElectric-List message posted by: "Dan Checkoway" <dan@rvproject.com>
Sandia SAE5-35. It has both serial & gray code output -- nice if you need
to feed a GPS (serial) as well as a transponder (typically gray code) and
don't feel like springing for a serializer. Easy to remove from its base,
which is easy to install. Other than that, I haven't flown with it yet, so
I can't vouch for anything but its specs or form factor.
)_( Dan
RV-7 N714D
http://www.rvproject.com
----- Original Message -----
From: <richard@riley.net>
Subject: AeroElectric-List: Altitude encoder recommendation?
> --> AeroElectric-List message posted by: richard@riley.net
>
> I have a new Microair transponder I'm installing. I have an ancient Terra
> encoder but I don't trust it, and I think I'm just going to chuck it and
> buy a new one.
>
> What do you all recommend? Transcal? Ack?
>
>
Message 15
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|
| Subject: | Re: Protecting LEDs |
--> AeroElectric-List message posted by: John R <jrourke@allied-computer.com>
Mike Heinen wrote:
>--> AeroElectric-List message posted by: "Mike Heinen" <mjheinen@adelphia.net>
>
>My understanding is the resistor is to get the voltage down to tolerable
>levels for the LED.
>
Close, but not quite. If the LED is rated at 3.6v, that's pretty much
what it will pull unless overdriven - and then it won't last very long
at all. What the resistor actually does is limit current - in fact, they
are known as "current-limiting" resistors in this circuit - but you
could put any kind of current limiter there, it's just that resistors
are the cheapest - but you have to size them properly.
You see, the LED is highly non-linear WRT current - it will "require"
very close to 3.6v over a wide range of current - anything from less
than 1 milliamp to 100 milliamps or more... less current and it's dim;
more current and it's brighter (up until it burns out) - but the voltage
stays pretty much the same over the range I mentioned. It's your job to
calculate the resistor value that will allow just the right amount of
current through - not enough resistance, and the current goes up and
reduces the life of the LED; too much resistance, and it may be dimmer
than you want.
The calculation is simple - the available voltage is 13.8v (typical main
bus voltage) minus the 3.6 volt that the LED will use... so you've got
10.2v across the resistor (or resistors if you like, but there's no good
reason in this case to use more than one) - and you want no more than
20mA to pass through it... ohm's law says E=IR or E/I=R... 10.2/.02 =
510 ohms.
Any higher resistance will mkae the light dimmer; any lower resistance
and you will be exceeding the rated current, possibly reducing the LED's
life. Actually, with your proposed 94 ohms resistance, the current will
be (E/R=I) or 10.2/94 = 0.11, or 110 milliamps - not a good idea... they
will get pretty hot, and expected life will definitely be reduced. Not
only that, but the power dissipated in each resistor (P=I
2*R) will be
47*.11*.11, or over 1/2 watt, requiring each resistor to be 1 watt
rating - relatively large!
> The long lead should be positive. THe LEDsI have are
>rated at 3.6 volts at 20 mA. I used 47 ohm resitors ...one on each side of
>the LEDs with the circuit being...
>
>12 volt battery positive >switch > 47 ohm resistor > Positive lead on led>
>Negative lead on led > + led >- led >+led > - led > 47 ohm resistor >
>negative ground.
>
>
A single 510-ohm resistor will get you the proper current, and will only
dissipate less than a quarter-watt, so a half-watt resistor would be the
proper choice. Why do you want to use two resistors?
-John R.
P.S.: Digikey has brighter LEDs with lower cost - but it does require a
bit of searching, they have so many! Here's an interesting one,
441-1008-ND on page
http://dkc3.digikey.com/PDF/T033/1199.pdf
Actually, this one is mounted in a wedge base for use with standard
automotive light sockets (although you'll probably never need to replace
it) - and it even apparently contains its own current-limiting resistor
(it has a 12-volt rating)!
Message 16
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| Subject: | Re: Hall sensor problem??? |
--> AeroElectric-List message posted by: "Larry & Gerry" <psychden@sonic.net>
I believe that the Hall sensor setup for the VM 1000 is designed to show alternator
output and not the system load directly. Until you run your engine (and
the alternator) you won't see anything but "0" on the "amps" display. Larry Ford
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