Today's Message Index:
----------------------
1. 06:43 AM - Re: Causes for epidemic horizon failures ? (Gilles.Thesee)
2. 06:48 AM - Ground Strap Location? (Joe Dubner)
3. 07:31 AM - Re: OV Module question for Bob (Gilles.Thesee)
4. 12:14 PM - Battery Drain (Ross Mickey)
5. 12:16 PM - Re: Instrument Panel Design (Eric M. Jones)
6. 01:07 PM - Re: Battery Drain (Matt Prather)
7. 01:17 PM - Re: Battery Drain (Scot Stambaugh)
8. 02:13 PM - Re: Battery Drain (Phil Birkelbach)
9. 03:44 PM - Re: Re: less expensive power supply with Aeroflash (czechsix@juno.com)
10. 05:51 PM - Re: Little recognition lights (jmfpublic@comcast.net)
11. 06:20 PM - Re: Causes for epidemic horizon failures ? (Alex Peterson)
12. 06:37 PM - Little recognition lights (David Burton)
13. 07:53 PM - Re: DC power panel minutia (Robert L. Nuckolls, III)
14. 07:53 PM - Re: Test Adapter (Robert L. Nuckolls, III)
15. 08:32 PM - Re: Ground Strap Location? (Robert L. Nuckolls, III)
16. 09:23 PM - Re: Test Adapter (Rick Fogerson)
Message 1
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Causes for epidemic horizon failures ? |
--> AeroElectric-List message posted by: "Gilles.Thesee" <Gilles.Thesee@ac-grenoble.fr>
>
> As you have noted, the query is devoid of supporting
> data to even begin development of a hypothesis. If
> I were to take a WAG at it, I'd look at mechanical
> issues first . . . vibration is the single most
> deleterious stress on gyro bearings. That presupposes
> that the person asking the question doesn't already
> KNOW that they've experienced a rash of electrical
> failures . . .
>
> Have them contact me directly and I'll make inquiries
> with local overhaul shops after we've deduced the
> logical investigative pathways to root-cause of
> the failures.
Bob,
Will do.
Thanks so much once more for your help.
Gilles
Message 2
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Ground Strap Location? |
--> AeroElectric-List message posted by: Joe Dubner <jdubner@yahoo.com>
B&C sells a braided bonding strap. The description of it states:
". . . Engine mounts should not be part of the electrical circuitry for
the engine; these bonding straps establish the appropriate pathway for
starter and alternator currents to the airframe. . . ."
(I have to take that with a grain of salt as my airplane is a Long-EZ,
so routing "starter and alternator currents to the airframe" is futile.
But they do need to route to the battery of course.)
If not an engine mount bolt, where specifically should the engine ground
strap connection be made. I'm particularly interested in the proper
location(s) for my Lycoming O-235 as it currently uses an engine mount
bolt.
Thanks,
Joe
Long-EZ 821RP
Clarkston, WA
Message 3
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: OV Module question for Bob |
--> AeroElectric-List message posted by: "Gilles.Thesee" <Gilles.Thesee@ac-grenoble.fr>
> >Bob, I did a couple of tests this evening before going ahead and shipping
> >this module over to you. I disconnected my starter motor. Now if I hit
the
> >start button the starter relay pulls in and the OV breaker does not trip.
> >This I assume means that if there is an OV condition it is being caused
by
> >the starter motor itself? Btw, wiring is as per fig 16 for the 912 and
my
> >module is built from the current cct diagram on your web site using the
two
> >transistors and zener.
> >
> >Is there anyone else on the list with a Rotax 912, wiring per fig.16 and
an
> >OV module??
>
> It's probably not a true OV condition that's tripping your
> module. There is a characteristic of silicon controlled
> rectifiers that makes the device itself sensitive to
> rapid changes (called dv/dt or change-in-voltage-with-
> respect-to-time) that can cause the SCR to trigger
> irrespective of the design intent of the circuit.
.......................
........................
>
> For what is worth, the vast majority of my experience
> with nuisance tripping of the crowbar SCR has been
> with Rotax installations ........
...................
...................
> I'm considering a new design that substitutes
> a boss-hog MOS-FET for the SCR. Totally free of
> dv/dt trigger effects. Until a few years ago,
> FETs that could stand up to the 300A crowbar
> impulse were expensive. They're getting cheaper
> all the time.
>
> Bob . . .
Bob,
When the time comes to fire our Rotax engine I'm concerned by the
possiblility of similar OV nuisance trips of our B&C module.
Our panel is already painted and equipped, and for space reasons we won't be
able to install a 2-10 switch in place of the present 2-3.
Just in case, do you think we could modify or buy a new OV module with a
big MOS-FET in the near future ?
Thanks,
Gilles
Message 4
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
--> AeroElectric-List message posted by: "Ross Mickey" <rmickey@ix.netcom.com>
I have hooked up my electrical system and all items check out. My problem
is that when I shut everything down, the battery goes dead in a few days.
Something in the system is obviously drawing current. How do I go about
trouble shooting this? All I can think of is to pull all the fuses, charge
the battery and replace the fuses one by one waiting a day or two between
each addition to see if the battery is being drained. There has to be a
faster solution but I am not electrical enough to figure it out.
All electric
One Lightspeed EI
Backup SD-8
One battery
Always hot, Essential and main buses (fuses)
What's always hot?
Electronic ignition
Cigarette lighter
Battery trickle charger
Interior light
Keep alive Dynon EFIS
Ross Mickey
RV6A N9PT
At the painters
Message 5
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Instrument Panel Design |
--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
Gary Casey's inquiry on panel design is hard to answer any better than the
three-part series by
Ricardo A. Price, in Kitplanes Dec95 and Jan96 and Feb96. I pore over this
stuff. I even have "Confusion in the Cockpit" from 1948 on the subject. But
everytime I want to make any comment on the subject I review Price's
articles and am re-impressed. I highly recommend getting the back issues
from Kitplanes (on line) if you have an interest in the subject. It's a real
keeper.
ps--Ricardo, can I get your email address?
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
Phone (508) 764-2072
Email: emjones@charter.net
For every complex problem, there is a solution that is simple, neat, and
wrong.
- H. L. Mencken
Message 6
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Battery Drain |
--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
Ross,
You have a good idea with pulling all of the fuses. As you thought,
there is a faster way to find the leak. What I think you need is to
use some instrumentation. The easiest way I can think of is to use
your multimeter on its amps setting (and connection). Connect the
ammeter in line between either of the batter cables. With all of the
fuses pulled/breakers open, you should read in the micro (u) range,
or less. If you read in the milli (m) range, you might have a problem
with the wiring somewhere.
If everything looks good so far, add one fuse at a time until you
note a significant increase in current demanded of the battery. If
you can't identify any offending circuit, its possible that you have
a tired, old battery that has a leak. Check this by disconnecting the
battery from the airplane, and letting it sit for a few days, and then
check its level of charge.
Good luck!
Regards,
Matt Prather
N34RD
> --> AeroElectric-List message posted by: "Ross Mickey"
> <rmickey@ix.netcom.com>
>
> I have hooked up my electrical system and all items check out. My
> problem is that when I shut everything down, the battery goes dead in a
> few days. Something in the system is obviously drawing current. How do
> I go about trouble shooting this? All I can think of is to pull all the
> fuses, charge the battery and replace the fuses one by one waiting a day
> or two between each addition to see if the battery is being drained.
> There has to be a faster solution but I am not electrical enough to
> figure it out.
>
> All electric
> One Lightspeed EI
> Backup SD-8
> One battery
> Always hot, Essential and main buses (fuses)
>
> What's always hot?
> Electronic ignition
> Cigarette lighter
> Battery trickle charger
> Interior light
> Keep alive Dynon EFIS
>
> Ross Mickey
> RV6A N9PT
> At the painters
>
>
Message 7
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Battery Drain |
--> AeroElectric-List message posted by: Scot Stambaugh <sstambaugh@qualcomm.com>
It is actually quite easy if you have a current meter. Remove the fuses
from the fuse block. Disconnect the positive terminal of the battery and
connect it to the positive terminal of the current meter, being careful to
keep it from comin into contact with the ship's ground. Connect the
negative terminal of the current meter to the positive post on the battery.
install the fuses one at a time to see if you get any current flow. You
may have more than one culprit so check all of the fuses for current
flow. How you deal with the offending circuit is for another E-mail. good
luck,
scot
At 12:13 PM 9/10/2003 -0700, you wrote:
>--> AeroElectric-List message posted by: "Ross Mickey" <rmickey@ix.netcom.com>
>
>I have hooked up my electrical system and all items check out. My problem
>is that when I shut everything down, the battery goes dead in a few days.
>Something in the system is obviously drawing current. How do I go about
>trouble shooting this? All I can think of is to pull all the fuses, charge
>the battery and replace the fuses one by one waiting a day or two between
>each addition to see if the battery is being drained. There has to be a
>faster solution but I am not electrical enough to figure it out.
>
>All electric
>One Lightspeed EI
>Backup SD-8
>One battery
>Always hot, Essential and main buses (fuses)
>
>What's always hot?
>Electronic ignition
>Cigarette lighter
>Battery trickle charger
>Interior light
>Keep alive Dynon EFIS
>
>Ross Mickey
>RV6A N9PT
>At the painters
>
>
Message 8
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Battery Drain |
--> AeroElectric-List message posted by: "Phil Birkelbach" <phil@petrasoft.net>
Take all the fuses out. Disconnect the (+) lead from the battery and put an
ammeter in series with the battery and the (+) lead. Start putting fuses
in. When you find the one that is pulling the amps it'll register on the
meter. The Dynon keepalive circuit will pull current all the time but it
should be a fairly low amount, and I don't understand the 'Battery Trickle
Charger' it may cause some grief. I assume that the LSE is on a switch and
is not really 'Always Hot' as is the interior light.
If you read current with all the fuses pulled then you may have a wiring
fault somewhere. What size battery do you have? If you know the Ah
(amp-hour) rating of the battery then you should be able to figure how much
current it would take to drain it in 48 hours. It would take roughly 350 mA
to drain a 17Ah battery in 48 hours. (somebody check my math). That's
pretty substaintial. The Dynon book says that it'll draw 1mA as long as the
internal battery is charged.
Oh don't hit the starter button with the ammeter in there unless you like
watching smoke rapidly escape from electrical test equipment. :-)
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Canopy
http://www.myrv7.com
----- Original Message -----
From: "Ross Mickey" <rmickey@ix.netcom.com>
Subject: AeroElectric-List: Battery Drain
> --> AeroElectric-List message posted by: "Ross Mickey"
<rmickey@ix.netcom.com>
>
> I have hooked up my electrical system and all items check out. My problem
> is that when I shut everything down, the battery goes dead in a few days.
> Something in the system is obviously drawing current. How do I go about
> trouble shooting this? All I can think of is to pull all the fuses,
charge
> the battery and replace the fuses one by one waiting a day or two between
> each addition to see if the battery is being drained. There has to be a
> faster solution but I am not electrical enough to figure it out.
>
> All electric
> One Lightspeed EI
> Backup SD-8
> One battery
> Always hot, Essential and main buses (fuses)
>
> What's always hot?
> Electronic ignition
> Cigarette lighter
> Battery trickle charger
> Interior light
> Keep alive Dynon EFIS
>
> Ross Mickey
> RV6A N9PT
> At the painters
>
>
Message 9
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: less expensive power supply with Aeroflash |
heads
--> AeroElectric-List message posted by: czechsix@juno.com
Hi Shaun,
Yes the Xpak 904 pulls a bit more power, but if keeping alternator loads really
light is a high priority, you don't have to choose between dollars or load....just
go with a lower power NOVA unit (or other commercial power supply manufacturer).
Then you'll save amps *and* dollars! Of course, your strobes won't
be as bright either. For me the Xpak 904 load is fine, I have a 40 A alternator
and a deluxe day/night VFR panel with dual 100 w landing lights etc etc and
my theoretical worst case load analysis with *everything* ON is 35 A (I'd be
surprised if in real life I ever see anything over 30 A). I could go full IFR
with my existing alternator and still not have any problems. Unless you're running
an air conditioner or something really power hungry you shouldn't have
problems with electrical loads (assuming a 40 A alternator...if you were going
to get by with the 20 A vac pad unit that B&C sells, you'd have to really be
careful but that's not suitable for most night VFR equipped aircraft...).
I think the NOVA flash pattern/rate is slightly more visible than Whelen's...I
haven't done any objective tests for this but watching my friend's RV-8 with the
Xpak 904 in the pattern with other aircraft equipped with Whelens or Aeroflash
systems, I'd give the nod to the Xpak for most attention-getting. In addition
to outright brightness, the higher flash rate seems to catch your eye better
than a slower rate. The ideal seems to be the really high rate you see on
emergency vehicles (which is usually a combination of several strobe systems
going at once) but these rates are too high to be legal for aircraft. So the
Xpak 904 still fits the bill perfectly if you want optimized flash power and rate
for half the price and 5X better warranty that the Whelen Cometflash offers...
--Mark Navratil
Cedar Rapids, Iowa
RV-8A N2D in painting hell....
From: "Shaun Simpkins" <shauns@hevanet.com>
Subject: AeroElectric-List: Re: less expensive power supply with Aeroflash heads
--> AeroElectric-List message posted by: "Shaun Simpkins" <shauns@hevanet.com>
Mark, all:
The X-pac 904 has some cool features.
It appears that although the Nova X-pac 904 beats the Whelen CometFlash supply
by 2:1 in price,
it does so at an extra 15% in current draw. This appears to be because the Whelen
flashes slower,
putting about 5% extra energy into each flash but at a 20% slower rate ( 55 vs.
70 / min ). So, if we
can believe the current draw specifications of each manufacturer, the Whelen puts
less load on your
alternator, the Nova less load on your wallet. A consideration for the power-efficient
OBAM ship...
Whelen is expensive, for sure...as the sole U.S. manufacturer of FAA-compliant
strobe heads and
power supplies, it can charge legal eagle builders what it wants. I agree, whatever
you decide
about the power supply, use the Whelen heads.
What I'd like some manufacturer to do is make a more efficient strobe power supply.
But if we're to
believe the input/output power specs that Nova quotes, strobe supplies are already
85% efficient. Not
much left to gain...
Shaun
The best thing to hit the internet in years - Juno SpeedBand!
Surf the web up to FIVE TIMES FASTER!
Message 10
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | RE: Little recognition lights |
--> AeroElectric-List message posted by: jmfpublic@comcast.net
Keith,
Here is the link to the Gilway catalog which has 8 G4 socket, using either
teflon or silicon insulation. The telephone number for sales in on each page
of this catalog. I'm sure you will find what you need.
http://www.gilway.com/pdf/allholders.pdf
Jim Foerster
Message 11
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Causes for epidemic horizon failures ? |
--> AeroElectric-List message posted by: "Alex Peterson" <alexpeterson@usjet.net>
> > As you have noted, the query is devoid of supporting
> > data to even begin development of a hypothesis. If
> > I were to take a WAG at it, I'd look at mechanical
> > issues first . . . vibration is the single most
> > deleterious stress on gyro bearings. That presupposes
> > that the person asking the question doesn't already
> > KNOW that they've experienced a rash of electrical
> > failures . . .
> >
> > Have them contact me directly and I'll make inquiries
> > with local overhaul shops after we've deduced the
> > logical investigative pathways to root-cause of
> > the failures.
Sorry I got in on this one late, but I have an interesting gyro story to
tell regarding vibration. I have a Sigmatek gyro in my plane, which is
made for Century Flight Systems (the gyro is vacuum, and gives input to
the autopilot system). Anyway, I had no problems for the first 300
hours or so, but then started noticing the gyro giving a nose down
indication during climbs. After leveling off, it would recover in a
minute or two. This sporadically happened over the last 60 hours or so.
It wasn't until last week when - duh - I correlated the pitch down with
engine rpm's. I typically climb at 2400 rpm, but pull it back to 2300
for cruise. There is something in the gyro which resonates when my
engine is at or near 2400 which causes it to show a nose down
indication. I moved the gyro forward in the airplane 1/2", mounting it
with little rubber vibration isolators, and presto, problem is gone. It
looks a little strange, but I'll come up with something to improve the
cosmetics. BTW, I had the dynamic balance of the prop checked, and it
was still in balance. I have no explanation for why the problem didn't
exist for the first 300 hours, except perhaps the intricate linkages
connecting the gyro to the "football" indicator might be getting a
little sloppy.
I happen to disagree with the above statement that vibration is the main
stress in gyros - hitting their stops while spun up has got to be the
highest stress that the gyro bearings see. The vibration levels, even
if they seem like a lot to ones finger, are still only very fractional g
loadings. The key is whether or not they drive something inside the
gyro at resonance, in which case, the forces could indeed be high.
Alex Peterson
Maple Grove, MN
RV6-A N66AP 372 hours
www.usfamily.net/web/alexpeterson updated with Van's homecoming photos!
Message 12
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Little recognition lights |
--> AeroElectric-List message posted by: "David Burton" <dburton@nwlink.com>
> Keith,
> Here is the link to the Gilway catalog which has 8 G4 socket, using either
> teflon or silicon insulation. The telephone number for sales in on each
page
> of this catalog. I'm sure you will find what you need.
> http://www.gilway.com/pdf/allholders.pdf
>
> Jim Foerster
I like Gilway a lot and have purchased hundreds of sockets from them in the
past. The last time I called them though they would not take an order from
me... They said that unless I ordered hundreds of one type at a time
(instead of hundreds of assorted which is how I order) they were not
interested in helping me.
I have been dealing with Bulbworks for sockets and Bulbman for lightbulbs.
Good luck!
http://www.bulbworks.com/sockets.html
Message 13
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: DC power panel minutia |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 11:30 PM 9/9/2003 -0400, you wrote:
>--> AeroElectric-List message posted by: Dj Merrill
><deej@thayer.dartmouth.edu>
>
>On Tue, 9 Sep 2003, Robert L. Nuckolls, III wrote:
>
> > This simple system will tell you within a few seconds that
> > the alternator has failed while it may take some time
> > (if ever) to catch the ammeter reading.
> > Bob . . .
>
> Yes, but IMHO you should be checking both if you have
>a lamp and a meter. Bulbs can die, and it is just good practice to
>scan all your gauges on occasion... :-)
That's why the lamp fixtures we ship are fitted with LEDs . .
and when driven from the main bus, the circuit gets pre-flight
tested when the master comes on and before the engine is started.
Bob . . .
Message 14
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Test Adapter |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 10:32 PM 9/9/2003 -0400, you wrote:
>--> AeroElectric-List message posted by: John Schroeder
><jschroeder@perigee.net>
>
>Bob -
>
>I missed this thread. Would you post the info on this test adaptor or where
>one could download it.
>
>Many Thanks,
>
>John
It's illustrated as a "patch" schematic in
http://www.aeroelectric.com/articles/Rev10/z10.pdf
figure Z-23.
Bob . . .
Message 15
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Ground Strap Location? |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 06:48 AM 9/10/2003 -0700, you wrote:
>--> AeroElectric-List message posted by: Joe Dubner <jdubner@yahoo.com>
>
>B&C sells a braided bonding strap. The description of it states:
>
>". . . Engine mounts should not be part of the electrical circuitry for
>the engine; these bonding straps establish the appropriate pathway for
>starter and alternator currents to the airframe. . . ."
>
>(I have to take that with a grain of salt as my airplane is a Long-EZ,
>so routing "starter and alternator currents to the airframe" is futile.
> But they do need to route to the battery of course.)
>
>If not an engine mount bolt, where specifically should the engine ground
>strap connection be made. I'm particularly interested in the proper
>location(s) for my Lycoming O-235 as it currently uses an engine mount
>bolt.
DC power ground should come through your firewall on a
5/16" (min) or 3/8" (better) brass bolt. This bolt may or
may not be associated with a firewall ground bus as illustrated
in http://www.bandc.biz/GroundBlock.html
The bonding strap should run from some bolt on the crankcase
to the firewall penetration stud . . . others on the list
can advise you of where they found suitable bolts on or near
the rear of their Lycoming engines.
A #2 ground wire continues forward from that bolt to a panel
ground bus and from there on forward to the battery (-) terminal.
See view -B- of
http://www.aeroelectric.com/articles/Appendix_Z_Drawings/z15ak.pdf
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
Message 16
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Test Adapter |
--> AeroElectric-List message posted by: "Rick Fogerson" <rickf@cableone.net>
I just noticed the resistor I bought was 1k ohm which I'm now thinking
probably means 1000 ohms. If that is true then is 1000 ohm, 1 watt resistor
okay instead of the one on the note 8 which has a 1k ohm, 1/2 watt resistor?
thanks, Rick
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
Subject: Re: AeroElectric-List: Test Adapter
> >Just a couple of questions on your test adapter (Note 8):
> >2) Radio Shack only had a 1 ohm, 1 watt resistor. Will it work and will
> >the readings be the same?
>
> The resistor is there to prevent damage to the instrumentation
> wire or disabling the alternator system should the wire become
> shorted to ground. 1-ohm is will put a pretty good load on the
> regulator . . . I'd rather see something bigger. The exact value is
> unimportant to readings . . . input resistance of the multimeter
> is many times higher. The protection resistor won't alter readings
> appreciably.
>
> I chose a 1-watt resistor for mechanical robustness. A larger
> value of resistance would be in order. I can send you something
> more suitable. Shoot me your mailing address.
>
> Bob . . .
>
>
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|