AeroElectric-Archive.digest.vol-at
April 05, 2002 - April 16, 2002
Red or White (REF. FAR 23.1397), 360 around the aircraft's vertical axis,
75 above and below the horizontal plane (REF. FAR 23.1401).
Joe Larson wrote:
>
> >
> > I did get one of these built... the flash rate and current draw meant that
> > it couldn't possibly be as bright as the FAA wants. (Not that that's a
> > problem for a homebuilt). Also, this is not a project for someone new to
> > electronics... there's enough energy in the system to kill you.
>
> Does anyone know how much power the FAA does want? How many
> watts should be going to each strobe? Is there a good place to look this
> up?
>
> -Joe
>
________________________________________________________________________________
| From: | lhdodge1(at)mmm.com |
22, 2000) at 04/05/2002 10:47:59 AM
I have decided to go the C/B route to protect individual pieces of
equipment. Digi-Key has some switchable C/B's by Tyco called W28 series in
the Digi-Key catalog, page 796. I like the idea of being able to switch off
a troublesome unit in case of fire. These C/B's are very economical. Do you
see any problem using these in a homebuilt?
Thanks,
Larry Dodge
lhdodge1(at)mmm.com
________________________________________________________________________________
| Subject: | Re: Why not E-bus alt feed from auxilliary battery |
too ?
Hi, Bob
T'was on a recent 4 seater kit the same model we are
> >building ! But we consider the wiring is not up to the rest of
the
> >airframe. Hence my questions.
> > (The flaps didn't even have limit switches.)
>
> Opps . . . all bets are off if the system suffers a failure
> mode that arises from a system design error. If he jammed a
> flap system and didn't open a fuse/breaker and end up killing
> the battery, there were far more thing wrong with that airplane
> than not having a second battery.
>
Certainly so. The reason we are gathering as much knowledge as we can.
>
> Flooded battery or RG?
>
I seem to remember having seen the battery installed on it's side on this
aiplane. So it must be some RG model...
> > >
> > > Batteries don't "fail" because they're capricious or
> > > obtuse, they fail because we've expected them to perform
> > > under conditions far beyond their capabilities to support
> > > and then blamed the battery for our misfortune and lack of
> > > understanding.
> >
> > Old tales die hard. My friend has fears about "shorted
batteries"
> >etc.
> >
> Understand. RG's don't flake off the plates and fill up the
> bilge with garbage like an OLD flooded cell will do.
>
Ah yes, fiber mats between the plates, or something ?
>
> What's a "complicated switch combination"? You've got a DC power
master
> and an aux battery master . . .
I was meaning not more complicated than that !
but I'm not sure you need a second battery
> just to power the fuel pump for a Rotax. Dual pumps but a maintained
> RG battery should be plenty of stored snort.
>
>
> Are you using Facet pumps? These critters draw only about 3A
> peak and less than 1A average.
They seem to be Pierburg models. A german brand found on VWs or BMWs. They
come with the engine.
Since you'd already signed up to the notion
> of buying a new battery every year, why not increase your payload
> by 15# and leave the "old" battery on the ground?
Well, we're already sold on the dual battery, so....
cheers,
Gilles
________________________________________________________________________________
| From: | Frank and Dorothy <frankv(at)infogen.net.nz> |
At 01:16 6/04/2002, you wrote:
>Does anyone know how much power the FAA does want? How many
>watts should be going to each strobe? Is there a good place to look this
>up?
My understanding was 10 Joules per flash. But I seem to recall that that's
being increased to 20 Joules. And I don't know how it applies to double- or
quad-flash systems. I don't know if a flash rate is specified either.
Assuming totally efficient electronics, 10 Joules per flash at 1 flash per
second is 10 Watts of power on average. I don't know how efficient the
circuit is at converting electricity to light... let's say its 90%
efficient. I really have no idea whether it should be 90% or 99%, but I'd
guess it wouldn't be less than 90% or you would have a fair amount of heat
being generated. But I could be completely outside the ballpark on this.
Maybe Bob could give us a ballpark figure?
So, to generate 10 Joules of light each second you need to input maybe 11
Watts of electricity. At about 12 Volts, that's about 0.9 Amps continuous
current draw. IIRC, the DIY design only pulled about 0.7 Amps.
I did talk to an electronics dude about the circuit... he said that
replacing the transformer would increase the current draw and consequently
provide a faster flash rate and/or brighter flashes. However, at that stage
I moved to a different town and lost contact with the whole thing.
HTH,
Frank.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Why not E-bus alt feed from auxilliary battery |
too ?
>
>
>Well, we're already sold on the dual battery, so....
>
>
>cheers,
>
>Gilles
Okay . . . yeaaahhhhh . . . but.
I've been thinking about loading your 18A alternator
with TWO battery contactors. That's about 10% of
your total used just to keep the batteries on line.
Of course, this goes away in an alternator-out situation.
Let's keep some options alive in the hip pocket. Maybe
the aux battery should be a little 4-8 a.h. battery
that's never used to support cranking and is paralleled
on to the system with an S704-1 power relay or something
similar. Relays like this take only 100 mA or so to close
them and since your #2 battery's primary duty is to support
a low current fuel pump, this might free up 800 mA or so
of main alternator output to do more useful things.
A smaller aux battery could save some weight too.
Have you added up the running loads for everything
you're going to have in the airplane?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: c/b question |
>I have decided to go the C/B route to protect individual pieces of
>equipment. Digi-Key has some switchable C/B's by Tyco called W28 series in
>the Digi-Key catalog, page 796. I like the idea of being able to switch off
>a troublesome unit in case of fire. These C/B's are very economical. Do you
>see any problem using these in a homebuilt?
None whatsoever . . . it's your airplane and your decision
as to how you'll devote time and dollars to assuage your
concerns. Any circuit breaker you want to pick is better
than no circuit breaker . . .
Have you read any of the published materials on our
website concerning flight system reliability? What
points have I missed that still have you convinced
that you what to play airborne systems analyst and
repair person?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
>
> >
> > I did get one of these built... the flash rate and current draw meant that
> > it couldn't possibly be as bright as the FAA wants. (Not that that's a
> > problem for a homebuilt). Also, this is not a project for someone new to
> > electronics... there's enough energy in the system to kill you.
>
> Does anyone know how much power the FAA does want? How many
> watts should be going to each strobe? Is there a good place to look this
> up?
>
>
>This is from Whelen's site
>3. Aircraft for which type certificate was applied for after July 18, 1977:
>These anti-collision systems must produce a minimum of 400 effective
>candela in aviation
>
>Red or White (REF. FAR 23.1397), 360 around the aircraft's vertical axis,
>75 above and below the horizontal plane (REF. FAR 23.1401).
Now . . . what can you do with that information?
This is why I suggested that you use a suitable flash-meter
as a transfer standard to compare one or more certified units
against your proposed substitution. Measuring the light
output with "calibrated" equipment can be very expensive by
comparison. Horizontal radiation from the strobe tubes is
enhanced/controlled by the cute little knobbies molded into
the lens surface. You can get by with fewer watt-seconds
total if you carefully craft the lenses to focus the energy
in desired directions. Alternatively, you can go the brute
force route with 30-40 watt-seconds of light per flash in
every direction and REALLY be seen.
This is not a simple task but it is doable. I'd do my homework
to show that my substitute is equal to or better
than anything certified. My first demonstration would be to
have an interested individual observe my airplane on a night-
time ramp next to one with a certified system. I'd show spherical
radiation data that supports what he can readily observe.
Don't ask if it's alright, tell him that it's better and
be able to show it. . . . and then see what happens.
It's a coin toss from there.
If you go out and try to actually measure the light output,
then you're starting to act like someone who is trying to
"certify" a new system . . . that completely changes
the mid-set of the inspector. He'll probably beg off and
refer you to someone who does accessory certifications
and THAT will open big cans of worms.
I'd approach it with a very low-key sell of equal-to-or-better-
than-certified for an experimental airplane and then pray
that he understands and agrees with the logic.
Bob . . .
________________________________________________________________________________
| From: | "Jim Robinson" <jbr(at)hitechnetworks.net> |
Does anyone have any info on how the proper way to tie wire
bundles using nylon lacing tape. Is there some trick to this?
Jim Robinson
________________________________________________________________________________
| From: | "Gabe and Marisol Ferrer" <ferrergm(at)bellsouth.net> |
| Subject: | Tefzel Harness for EIS |
I spoke with Gregg (Grand Rapids Technologies, EIS) today about buying a
tefzel harness for my EIS. He said that he will be offering it in the next
two to three weeks. He's found a supplier that will supply tefzel wire in
many colors.
Gabe A Ferrer
ferrergm(at)bellsouth.net
Cell: 561 758 8894
Night or FAX: 561 622 0960
________________________________________________________________________________
| From: | "Jim Cameron" <toucan(at)78055.com> |
"Lancair Mail List"
| Subject: | Ritchie Electronic Compass |
For what it's worth, I've just replaced my Ritchie electronic compass
with an R.C. Allen electric DG. The Ritchie compass looked very attractive
when I was designing my panel -- new technology, no precession, light
weight, and quite inexpensive (about $260, as I recall). After some flight
hours with it, however, I elected to replace it with the old-tech RC Allen
model. The Ritchie compass was sluggish, hard to read (I got the 2" job,
although they do make a larger one), and didn't like extreme bank angles.
It also did the E.I. fuel gauge trick: when you key the mic to transmit on
your COM, the Ritchie compass goes nuts (along with the E.I. fuel gauge).
Seems that neither of these instruments like stray RF.
I went through the compensating procedure for the Ritchie compass, and
it seemed to go about 10 degrees further off each time! Too bad -- with all
the nifty solid-state compass-type gizmos on the market, there should be a
better mousetrap out there at an affordable price. To be fair, Ritchie
don't sell this model for aircraft use, and would probably have a small fit
if they knew that's what I bought if for. I now have the Aerolectrics
all-electric panel on a more seriously stressed budget than before. The
R.C. Allen model is sure bargain, compared to the vacuum model. For about a
grand more, you get no heading bug and no autopilot pick-off. Just yer
basic DG.
Jim Cameron
Lancair Super ES, N143ES
________________________________________________________________________________
| From: | "Ronald A. Cox" <racox(at)ix.netcom.com> |
>Thank God for Bob Nuckolls!
>
>Pat Hatch
>RV-4 Flying
>RV-6 Firewall Foreward
>Vero Beach, FL
You better believe it! I have on a regular basis!!! This is tough enough
WITH his help, I can't imagine slogging through without it.
Ron Cox
________________________________________________________________________________
| From: | "Gabe and Marisol Ferrer" <ferrergm(at)bellsouth.net> |
| Subject: | Tefzel Harness for EIS |
I spoke with Gregg (Grand Rapids Technologies, EIS) today about buying a
tefzel harness for my EIS. He said that he will be offering it in the next
two to three weeks. He's found a supplier that will supply tefzel wire in
many colors.
Gabe A Ferrer
ferrergm(at)bellsouth.net
Cell: 561 758 8894
Night or FAX: 561 622 0960
________________________________________________________________________________
| From: | George Braly <gwbraly(at)gami.com> |
| Subject: | RE: New "Special Conditions" for FADEC systems - - |
?
Bob,
Have you seen the FAA's new "special conditions" for certification of
FADECs.
This is a HIRF deal where they have decided to allow testing of the systems
in an unprotected environment (ie, no airframe around the systems) at a
level of 100V/meter from 10KHz to 18GHz.
Passing this test would meet the full up requirements for these systems that
are then installed in the protective environment of the airframe.
At least, that is what I took from it, on a first read.
If you do the testing in an airframe, some of the requirements go up to
3000V/meter in some of the higher frequencies.
Any thoughts on this subject?
Regards, George
-----Original Message-----
From: Gabe and Marisol Ferrer [mailto:ferrergm(at)bellsouth.net]
Subject: AeroElectric-List: Tefzel Harness for EIS
I spoke with Gregg (Grand Rapids Technologies, EIS) today about buying a
tefzel harness for my EIS. He said that he will be offering it in the next
two to three weeks. He's found a supplier that will supply tefzel wire in
many colors.
Gabe A Ferrer
ferrergm(at)bellsouth.net
Cell: 561 758 8894
Night or FAX: 561 622 0960
http://www.matronics.com/browselist/aeroelectric-list
________________________________________________________________________________
| From: | deltab(at)erols.com |
| Subject: | Lead acid storage batteries. |
For personal enrichment: this is how the other half lives.
(hint:download first)
<<http://m4ruby.ece.jhu.edu/library/nstm/223v1r2a.pdf>>
The DOE had some links to valved SLA batteries. I'll see if the links still exist.
Bernie C.
________________________________________________________________________________
| From: | "Richard M. Martin" <martinrm(at)ncplus.net> |
Tie with a clove hitch followed with a square knot. Cut ends about a 1/4"
from the knot.
Richard
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Jim
Robinson
Subject: AeroElectric-List: RE: wire tying
Does anyone have any info on how the proper way to tie wire
bundles using nylon lacing tape. Is there some trick to this?
Jim Robinson
http://www.matronics.com/browselist/aeroelectric-list
________________________________________________________________________________
| Subject: | Why not E-bus alt feed from auxilliary battery too |
?
> Okay . . . yeaaahhhhh . . . but.
>
> I've been thinking about loading your 18A alternator
> with TWO battery contactors. That's about 10% of
> your total used just to keep the batteries on line.
Oh , we didn't think of that.
>
> Of course, this goes away in an alternator-out situation.
> Let's keep some options alive in the hip pocket. Maybe
> the aux battery should be a little 4-8 a.h. battery
> that's never used to support cranking and is paralleled
> on to the system with an S704-1 power relay or something
> similar. Relays like this take only 100 mA or so to close
> them and since your #2 battery's primary duty is to support
> a low current fuel pump, this might free up 800 mA or so
> of main alternator output to do more useful things.
We'll dig into it. But then, we'll have to perform capacity checks.
>
> Have you added up the running loads for everything
> you're going to have in the airplane?
>
Just a rough estimate, as we're still in the choice phase.
The airplane is primary to fly day VFR since French regulations forbid night
VFR or IFR operations in an experimental class aircraft. But who knows...
The equipment list, still mainly on paper, includes :
Main always running fuel pump (Pierburg models, Rotax table reads from 2 to
a max of 3 amps)
Backup fuel pump
Turbo control unit (current draw unknown to date)
Becker radio
Becker XPDR
Sigtronic intercom
Handheld GPS (to be followed by moving map NAV system when direct sun
readable displays will be available)
Electric horizon (no DG for the time being)
Electric turn coordinator
Electric engine and fuel gauges
Annunciator lights
Instruments internal lighting
Panel EL lighting (may include 9 v battery backup)
Nav lights
Dual or triple strobes
2 landing lights
Pitch trim motor
Maybe aileron trim motor
Flap motors
What would be your best bid for battery capacity ?
Thanks,
Gilles
________________________________________________________________________________
| From: | "Piers Herbert" <piers.herbert(at)ntlworld.com> |
| Subject: | Re: Why not E-bus alt feed from auxilliary battery |
too ?
> Becker radio
> Becker XPDR
> Sigtronic intercom
> Handheld GPS (to be followed by moving map NAV system when direct sun
> readable displays will be available)
Hi Gilles,
Have you looked at the Filser range of avionics? They are developing a mode
S transponder which may become mandatory for VFR in Europe in 2008 (little
point in fitting a mode A transponder if it will be oboslete in a few
years). They also have a moving map which they reckon to be sunlight
readable (DX400). They now have a panel mount version of this which has the
connectors on the back, not on the side. See:
http://www.filser.de/filsere.html
Piers
________________________________________________________________________________
| From: | "Piers Herbert" <piers.herbert(at)ntlworld.com> |
> My understanding was 10 Joules per flash. But I seem to recall that that's
> being increased to 20 Joules. And I don't know how it applies to double-
or
> quad-flash systems. I don't know if a flash rate is specified either.
Flash rate is 40 to 100 per minute (or up to 180 where visibility from two
flash heads overlap).
The question is how does Joules per flash relate to "effective" intensity in
candelas as defined in FAR/JAR 23.1401? There is an awkward looking equation
in there which I don't feel like tackling!
I am considering the sky flash strobes for my project
http://www.airworlduk.com/skyflash.html
These quote 52 joules per cycle, but by "cycle" they might mean a double
flash. I have e mailed them to ask if they meet the requirements of JAR
23.1401.
They have two lens options (same electrics) The "Fresnel" lens is claimed to
concentrate the light where it is most needed (i.e horizontal plane).
I think I might put one streamline head on the top of the VS and one Fresnel
head under the fuselage.
Piers
________________________________________________________________________________
| Subject: | Re: Why not E-bus alt feed from auxilliary battery |
too ?
> Hi Gilles,
>
> Have you looked at the Filser range of avionics? They are developing a
mode
> S transponder which may become mandatory for VFR in Europe in 2008 (little
> point in fitting a mode A transponder if it will be oboslete in a few
> years). They also have a moving map which they reckon to be sunlight
> readable (DX400). They now have a panel mount version of this which has
the
> connectors on the back, not on the side. See:
>
> http://www.filser.de/filsere.html
>
Piers,
You're right about transponder modes. We were thinking of mode C.
Interesting website. We'll look further into it.
thanks,
Gilles
gilles
________________________________________________________________________________
| From: | czechsix(at)juno.com |
OR.....instead of going through all this light meter stuff, you can just
get a non-aviation power supply that has specs in joules delivered to the
strobe heads that are comparable to that of an approved aviation system
and my bet is that's more than enough for the average FAA inspector. I
got a NOVA X-PAK 904, which after a lot of research was and still is the
absolute best commercial strobe power pack available for the money. It's
a 90 Watt unit and delivers joules-per-strobe (up to four head)
comparable to Whelen's HDA-CF Cometflash system (which is the most
powerful multi-strobe aviation supply on the market). The only
disadvantage to the NOVA power pack is the price is about a third of the
Whelen system, and the warranty is 5 years instead of 1 (or 2?) for the
Whelen. Well I guess ya can't have it all... : ) Before inundating me
with dozens of questions I've already answered, search the RV-List
archives for "Cometflash on a beer budget" ....you'll only get a few
hits, and it's ALL there in exhaustive, nauseating detail.
--Mark Navratil
Cedar Rapids, Iowa
RV-8A sanding fiberglass, wishing I was at Sun & Fun...
_______
From: "Robert L. Nuckolls, III" <nuckolls(at)kscable.com>
Subject: AeroElectric-List: Strobes:
>
> >
> > I did get one of these built... the flash rate and current draw meant
that
> > it couldn't possibly be as bright as the FAA wants. (Not that that's
a
> > problem for a homebuilt). Also, this is not a project for someone new
to
> > electronics... there's enough energy in the system to kill you.
>
> Does anyone know how much power the FAA does want? How many
> watts should be going to each strobe? Is there a good place to look
this
> up?
>
>
>This is from Whelen's site
>3. Aircraft for which type certificate was applied for after July 18,
1977:
>These anti-collision systems must produce a minimum of 400 effective
>candela in aviation
>
>Red or White (REF. FAR 23.1397), 360 around the aircraft's vertical
axis,
>75 above and below the horizontal plane (REF. FAR 23.1401).
Now . . . what can you do with that information?
This is why I suggested that you use a suitable flash-meter
as a transfer standard to compare one or more certified units
against your proposed substitution. Measuring the light
output with "calibrated" equipment can be very expensive by
comparison. Horizontal radiation from the strobe tubes is
enhanced/controlled by the cute little knobbies molded into
the lens surface. You can get by with fewer watt-seconds
total if you carefully craft the lenses to focus the energy
in desired directions. Alternatively, you can go the brute
force route with 30-40 watt-seconds of light per flash in
every direction and REALLY be seen.
This is not a simple task but it is doable. I'd do my homework
to show that my substitute is equal to or better
than anything certified. My first demonstration would be to
have an interested individual observe my airplane on a night-
time ramp next to one with a certified system. I'd show spherical
radiation data that supports what he can readily observe.
Don't ask if it's alright, tell him that it's better and
be able to show it. . . . and then see what happens.
It's a coin toss from there.
If you go out and try to actually measure the light output,
then you're starting to act like someone who is trying to
"certify" a new system . . . that completely changes
the mid-set of the inspector. He'll probably beg off and
refer you to someone who does accessory certifications
and THAT will open big cans of worms.
I'd approach it with a very low-key sell of equal-to-or-better-
than-certified for an experimental airplane and then pray
that he understands and agrees with the logic.
Bob . . .
________________________________________________________________________________
| From: | Jerzy Krasinski <krasins(at)email.ceat.okstate.edu> |
Unfortunately, conversion efficiency of Xenon flashtubes is much lower than
90%. It depends on driving current and pressure of Xenon in the tube,
generally increasing with the pressure. Unfortunately, increasing Xenon
pressure requires to use higher voltage to get discharge. In laser
flashlamps which are well characterized and operate at high voltage around
1000V the conversion efficiency into visible light is roughly 30%. Small
flashtubes for strobes operate at around 200V and their efficiency is lower
but I do not know the number. But Xenon lamp efficiency is much higher than
typical 4% for an incandescent bulb.
Jerzy Krasinski
----- Original Message -----
From: "Frank and Dorothy" <frankv(at)infogen.net.nz>
Subject: AeroElectric-List: Re: Strobes
>
> At 01:16 6/04/2002, you wrote:
> >Does anyone know how much power the FAA does want? How many
> >watts should be going to each strobe? Is there a good place to look this
> >up?
>
> My understanding was 10 Joules per flash. But I seem to recall that that's
> being increased to 20 Joules. And I don't know how it applies to double-
or
> quad-flash systems. I don't know if a flash rate is specified either.
>
> Assuming totally efficient electronics, 10 Joules per flash at 1 flash per
> second is 10 Watts of power on average. I don't know how efficient the
> circuit is at converting electricity to light... let's say its 90%
> efficient. I really have no idea whether it should be 90% or 99%, but I'd
> guess it wouldn't be less than 90% or you would have a fair amount of heat
> being generated. But I could be completely outside the ballpark on this.
> Maybe Bob could give us a ballpark figure?
>
> So, to generate 10 Joules of light each second you need to input maybe 11
> Watts of electricity. At about 12 Volts, that's about 0.9 Amps continuous
> current draw. IIRC, the DIY design only pulled about 0.7 Amps.
>
> I did talk to an electronics dude about the circuit... he said that
> replacing the transformer would increase the current draw and consequently
> provide a faster flash rate and/or brighter flashes. However, at that
stage
> I moved to a different town and lost contact with the whole thing.
>
> HTH,
>
> Frank.
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| From: | "Fergus Kyle" <VE3LVO(at)rac.ca> |
| Subject: | Professional or Commercial? |
Bob:
"> That's the real answer..... Hams are amateurs - that is,>professionals
>who don't/can't charge for their services.
. . not necessarily so. They are prohibited from charging for their message
services offered by virtue of their "experimental and educational use of the
airwaves" but they're not prohibited from charging for technical services."
Ok, Bob, I am speaking of Canada, UK and the Antipodes and may
be out of my depth in the US. I have yet to hear of an amateur demanding
money to measure an antenna for anybody.
"..Used to do troubleshooting and repairs for a number of other hams in my
neighborhood when I was a teenager. They were old enough and smart enough to
know that crawling up that tower to tweak and antenna was much more
hazardous than staying on the ground and watching me do it."
Yup, me too - and still do. But never charged a sou for it.
"You need to be a little cautious about some off the shelf SWR meters used
at CB and lower amateur band frequencies. "
Agreed - I think you need to be cautious about ANY CB item, but
the accepted ham Antenna Analyzer is now over ten years old and answers most
antenna challenges. The problem is unknowing borrowers blow a watt through
them and they are toast. That's why a ham comes with it. Good to 500MHz,
too, with accessories.
"We just assumed that the SWR bridge we used with good results at 30 Mhz
would be good at 146 Mhz"
Uh, oh. Can't do that.... I guess we all have done that at one
time or another.
"I became a "professional" antenna builder that day."
But still an amateur I'll bet.
I'll stick to my guns though. I've pulled more two-dollar
digital clocks from Cessnas than I wanted to but never charged a penny. The
crystal from TV plays hell with the DF. It wouldn't occur to charge for it
though.
As they say in the movies, "73, Oh-Em"
Ferg
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
>
>
>Does anyone have any info on how the proper way to tie wire
>bundles using nylon lacing tape. Is there some trick to this?
>
>Jim Robinson
Nothing fancy . . . but here's some tips from someone who has
used up more spools of tie string than he'd like to remember. . .
http://209.134.106.21/articles/cable_lace/cable_lace.html
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Tefzel Harness for EIS |
>
>
>I spoke with Gregg (Grand Rapids Technologies, EIS) today about buying a
>tefzel harness for my EIS. He said that he will be offering it in the next
>two to three weeks. He's found a supplier that will supply tefzel wire in
>many colors.
>
>Gabe A Ferrer
>ferrergm(at)bellsouth.net
>Cell: 561 758 8894
>Night or FAX: 561 622 0960
Good for you . . . and good for EIS. There's nothing like
friendly pressure and good critical review to help our
favorite suppliers continue to be our favorite suppliers.
Bob . . .
________________________________________________________________________________
| From: | "Dave" <dave(at)bestnetpc.com> |
| Subject: | Re: RE: wire tying |
Be careful. Some time ago ( I think on this news group ) a similar topic
came up and warned that some of the lacing was not fireproof. I went out
to my shop and picked up a roll that I got when I worked for Grumman.
When I put a lighter to it, the stuff burned like a fuse on a
firecracker! Into the trash it went. Damn. Test yours, Dave.
----- Original Message -----
From: Robert L. Nuckolls, III
To: aeroelectric-list(at)matronics.com
Sent: Saturday, April 06, 2002 5:13 PM
Subject: AeroElectric-List: RE: wire tying
>
>
>Does anyone have any info on how the proper way to tie wire
>bundles using nylon lacing tape. Is there some trick to this?
>
>Jim Robinson
Nothing fancy . . . but here's some tips from someone who has
used up more spools of tie string than he'd like to remember. . .
http://209.134.106.21/articles/cable_lace/cable_lace.html
Bob . . .
=
=
messages.
=
http://www.matronics.com/browselist/aeroelectric-list
=
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Professional or Commercial? |
>
>Bob:
>"> That's the real answer..... Hams are amateurs - that is,>professionals
> >who don't/can't charge for their services.
>. . not necessarily so. They are prohibited from charging for their message
>services offered by virtue of their "experimental and educational use of the
>airwaves" but they're not prohibited from charging for technical services."
> Ok, Bob, I am speaking of Canada, UK and the Antipodes and may
>be out of my depth in the US. I have yet to hear of an amateur demanding
>money to measure an antenna for anybody.
There's a difference between demanding money and being prohibited
from charging money. I do a lot of things for people where I don't
get paid and lots of things for which I do get paid. I'd be really
bent out of shape if some bureaucrat stepped up to tell me how any
particular situation was supposed to play.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
>
>Be careful. Some time ago ( I think on this news group ) a similar topic
>came up and warned that some of the lacing was not fireproof. I went out
>to my shop and picked up a roll that I got when I worked for Grumman.
>When I put a lighter to it, the stuff burned like a fuse on a
>firecracker! Into the trash it went. Damn. Test yours, Dave.
There are no "fireproof" tie strings . . . all kinds of synthetic
tie strings are used all over the airplanes. Tye-wraps
aren't fire proof either . . . most are made of Nylon. As
tying materials, these products are introduced in such small
volumes that their relative performance in flame/fume testing
isn't significant . . . Consider that you've got perhaps 200
pounds of gasoline in the tanks and 10 pounds of oil in the
sump and neither of those will pass the flame tests either
but these materials are contained and controlled in the best
way that we know and we choose to live with their potential
for hazard.
Bob . . .
________________________________________________________________________________
| From: | Michael Hartmann <hartmann(at)sound.net> |
| Subject: | Re: RE: wire tying |
>
>Be careful. Some time ago ( I think on this news group ) a similar topic
>came up and warned that some of the lacing was not fireproof. I went out
>to my shop and picked up a roll that I got when I worked for Grumman.
>When I put a lighter to it, the stuff burned like a fuse on a
>firecracker! Into the trash it went. Damn. Test yours, Dave.
You could do the same test with zip tie. Be ready to put out the fire on
your shoes started by the dripping flaming fireballs. It's a pretty cool
effect.
- Mike
________________________________________________________________________________
| From: | "Jim Robinson" <jbr(at)hitechnetworks.net> |
| Subject: | Re: switch wiring |
Bob, all
When wiring a switched item is it better to run power to the item
and switch the ground, or run power to the switch then to the item
Jim Robinson
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Ritchie Electronic Compass |
>
> For what it's worth, I've just replaced my Ritchie electronic compass
>with an R.C. Allen electric DG. The Ritchie compass looked very attractive
>when I was designing my panel -- new technology, no precession, light
>weight, and quite inexpensive (about $260, as I recall). After some flight
>hours with it, however, I elected to replace it with the old-tech RC Allen
>model. The Ritchie compass was sluggish, hard to read (I got the 2" job,
>although they do make a larger one), and didn't like extreme bank angles.
Because magnetic lines of force over the surface of the earth are
parallel to the surface only at the equator, any heading measurement
device dependent solely upon magnetic vector sensing will be accurate
only in straight and level flight. Times when magnetic heading are
most needed is during flight in IMC where my instructors suggested
it was best to limit one's turns to standard rate . . . but even then,
depending on entry and exit headings for a turn, the purely magnetic
sensor will show significant and observable error.
The technique for utilizing such a device would take some pilotage
wherein you reduce bank angle as you approach the final heading.
If you're down to 1 degree/second as you slide up to the target heading,
errors will be very small and the guy watching you on radar won't
know the difference.
>It also did the E.I. fuel gauge trick: when you key the mic to transmit on
>your COM, the Ritchie compass goes nuts (along with the E.I. fuel gauge).
>Seems that neither of these instruments like stray RF.
Hmmmm . . . boats have powerful VHF and HF radios . . . I'm surprised
that the marine product was so deficient in this regard. Unfortunate.
> I went through the compensating procedure for the Ritchie compass, and
>it seemed to go about 10 degrees further off each time!
Don't understand "each time" . . . are you saying that their procedure
produced divergent results with each new heading during a compass-
swing operation or were the best-achievable results increasingly
inaccurate each time the swing procedure was performed?
> Too bad -- with all
>the nifty solid-state compass-type gizmos on the market, there should be a
>better mousetrap out there at an affordable price. To be fair, Ritchie
>don't sell this model for aircraft use, and would probably have a small fit
>if they knew that's what I bought if for.
Agreed. But what you tried wasn't even around to be tried 10 years ago
and there will be better products 10 years hence. I appreciate your
willingness to sample the market and give us all feedback on the
experience.
> I now have the Aerolectrics
>all-electric panel on a more seriously stressed budget than before. The
>R.C. Allen model is sure bargain, compared to the vacuum model. For about a
>grand more, you get no heading bug and no autopilot pick-off. Just yer
>basic DG.
In conversations with several builders, I've suggested that
they punch a hole for the DG and put a cover plate over it until
they've finished the airplane and have had a chance to evaluate
their flight system capabilities with the other installed
instruments. In other words, suppose your standard modus-operandi
was "partial panel"? Given that GPS gives us dead-nuts accurate
course over the ground, could one fly as well without the
DG?
A second thing to consider is that an electric DG costs about the
same as a Nav-Aid autopilot. Would one be better off having a
dual Nav-Aids each capable of flying a ground track coupled to
GPS (one panel mounted, the other perhaps your hand-held backup)?
Given that our airplanes are NOT going to suffer an electrical
emergency, might we be better advised to consider dual autopilots
as opposed to a panel full of round things that offer two to
five different ways to get around in clouds?
Burt Rutan has often talked about "highways in the sky" and
waxed eloquently about what the future of avionics can bring.
I've seen some of the "highways" work in the AGATE program and
while it's pretty neat stuff it is also very complex and
heavily dependent upon software that's increasingly difficult
to produce bug-free and certifiable. In the mean time, we have
elegant, simple alternatives to older technologies that offer
a tremendous return on investment.
The box of tinker-toys is changing all the time and as purveyors
and users of leading-edge technologies, the experimental aviation
community is in the BEST position to show the rest of the world
how to get the best performance for the dollar. We can best do
this by asking "gee, what if?" and go out and try it.
Thank you for this important data point Jim . . . I hope this
experience won't seriously discourage you from sticking your
toe into the waters of future opportunities to advance the
art and science of our craft.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: New "Special Conditions" for FADEC systems - - |
?
>
>
>Bob,
>
>Have you seen the FAA's new "special conditions" for certification of
>FADECs.
>
>This is a HIRF deal where they have decided to allow testing of the systems
>in an unprotected environment (ie, no airframe around the systems) at a
>level of 100V/meter from 10KHz to 18GHz.
>
>Passing this test would meet the full up requirements for these systems that
>are then installed in the protective environment of the airframe.
>
>At least, that is what I took from it, on a first read.
>
>If you do the testing in an airframe, some of the requirements go up to
>3000V/meter in some of the higher frequencies.
>
>Any thoughts on this subject?
I've made a deliberate effort to isolate myself from things
like FADEC . . . this concept may make a lot of sense for
big airplanes where 100' of fuselage separates cockpit and
engine but I think the current approaches applied to single
engine airplanes is silly. I don't see where the user gets
a good return on his investment . . . engine performance
is improved only marginally over full manual controls. It's
obviously easier to use but in the grand scheme of things,
engine management is pretty low in heap of things pilots
can mis-manage and get into trouble.
I'd be interested in seeing the rational for increasing
RFI resistance on this or any other accessory. I've done
quite a bit of qualification testing for military products
and except for carrier flight deck operations, 200 v/m
has been sufficient to satisfy the military for everything
except stuff that blows up. In these cases we went to China
Lake and sprayed our gizmos with god-awful RF levels . . .
for the few systems that might have been vulnerable,
it wasn't difficult to protect them.
I'm wondering what the FAA considers potential sources of
threat? On trips back from Hutchinson to Wichita the
route of flight takes one within a mile of a
cluster of five 1000' towers capped with multi-kilowatt
broadcast antennas. As I've passed these facilities dozens
of times, I've watched things on the panel for any
observable effects. To date, none have been noticed even
in my el-cheapo hand held stuff. It's hard to imagine what
kind of threats out there are any larger.
Like all agencies charged mandating regulation aimed
at achieving utopian isolation from risk, I suspect
that many changes are due to perception creep . . .
"Gee guys, we worried a lot about 100 v/m last year,
should we be worrying about 200 v/m this year?" This
is all happening in an era when we're figuring out how
to do amazing things with LESS radiated power, not more.
GPS signals are so weak that they're barely readable above
the atmospheric noise floor.
It would be interesting to see if hazards worthy of these
"special conditions" have been identified an scientifically
evaluated for risk. One thing is certain . . . it's not
going to get any easier to do anything in the certified
world.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Lead acid storage batteries. |
>
>For personal enrichment: this is how the other half lives.
>(hint:download first)
>
><<http://m4ruby.ece.jhu.edu/library/nstm/223v1r2a.pdf>>
>
>The DOE had some links to valved SLA batteries. I'll see if the links
>still exist.
>
>
>Bernie C.
Neat document. I'll retain it for reference. It's
interesting to see how much time and effort an organization
can put into maintaining and understanding batteries when
the future of ship and crew may depend on getting the last
watt-hour of energy stored . . . and then compare efforts
to another institution that has recorded perhaps thousands
of dark-n-stormy-night stories about what they experienced
when their battery fell short of basic needs because
it was mis-understood, abused and ignored.
Bob . . .
________________________________________________________________________________
| Subject: | Wiring from scratch : where do you start ? |
Hi Bob and all,
Could you give me some hints on where to begin when you actually start to
wire your airplane ?
Once the diferent systems have been decided, and the schematic is complete,
how do you decide which wire to route in which bundle, and where ?
I've gathered quite a wealth of information, including AC 43-13, along with
your book and the posts on this list, and performed some fumbling on several
airplanes, but devising something from scratch is another story.
Thanks
Gilles
________________________________________________________________________________
| From: | "Stein Bruch" <stein(at)steinair.com> |
| Subject: | Wiring from scratch : where do you start ? |
Gilles,
Depending on your construction methods, it really is beneficial to run some
of the wiring early in the building process. For example, wires to the tail
(lights, trim, etc..) are much easier to install and run with the fuse open.
Likewise with installing "conduits" to slip wiring through in the wings and
sometimes in the fuselage. I added different wires throughout the process
of building and "hopefully" just finished this weekend.
Cheers,
Stein Bruch
RV6, Minneapolis.
<Gilles.Thesee@ac-grenoble.fr>
Hi Bob and all,
Could you give me some hints on where to begin when you actually start to
wire your airplane ?
Once the diferent systems have been decided, and the schematic is complete,
how do you decide which wire to route in which bundle, and where ?
I've gathered quite a wealth of information, including AC 43-13, along with
your book and the posts on this list, and performed some fumbling on several
airplanes, but devising something from scratch is another story.
Thanks
Gilles
________________________________________________________________________________
| Subject: | Re: Wiring from scratch : where do you start ? |
> Depending on your construction methods, it really is beneficial to run
some
> of the wiring early in the building process. For example, wires to the
tail
> (lights, trim, etc..) are much easier to install and run with the fuse
open.
> Likewise with installing "conduits" to slip wiring through in the wings
and
> sometimes in the fuselage. I added different wires throughout the process
> of building and "hopefully" just finished this weekend.
>
> Cheers,
> Stein Bruch
> RV6, Minneapolis.
>
Stein,
Thanks for responding.
In fact, some of our equipment is already in place : trim motor, flap
motors. Fortunately the fuselage construction permits easy access to the
tail. So wiring the tail strobe won't be a problem.
But I'm still wondering where we'll route things behind the panel. I'd like
to be able to draw something coherent before starting cutting wire and
crimping. And devise a methodical wire marking scheme before the begining.
Cheers,
Gilles
________________________________________________________________________________
| From: | Mike Thompson <grobdriver(at)yahoo.com> |
| Subject: | Re: Wiring from scratch : where do you start ? |
--- "gilles.thesee" <Gilles.Thesee@ac-grenoble.fr> wrote:
> But I'm still wondering where we'll route things behind the panel.
> I'd like
> to be able to draw something coherent before starting cutting wire
> and
> crimping.
My 2 cents:
Start with two sources: Power and ground
If you are using a ground bus (recommended), it will be directly behind
the same bus on the engine side of the firewall. Where you have free
space to mount the ground lug and bus connection on the engine side
will determine where on the cockpit side your ground bus goes.
Once that is determined, you can start putting together wire bundles of
ground wires from your panel gadgets and run them all to the bus along
convenient braces, ribs and such. Avoid leaving a spaghetti of wires
hanging in space behind the panel.
I am using a main and essential power bus fuse block. I've mounted it
so that I could swing the fuse block down for maintenance. Where I had
the space for the swinging mount determined their location behind the
panel. Then wire power bundles to the fuse blocks.
Now all instrument-to-instrument wiring can be done separately - but
you have a start with power and ground.
> And devise a methodical wire marking scheme before the beginning.
The best (and least expensive) way to mark your wires (in my opinion)
has been mentioned several times and has you use printed labels on
plain paper rolled around the wire and covered with clear heat shrink.
Print something like:
Master Power
Master Power
Master Power
Master Power
then when you roll it around the wire, some part of it will be
readable.
Extend your heat shrink beyond the label by 1/4" or so.
YMMV
Mike Thompson
Austin, TX
-6 N140RV (Reserved)
Firewall Forward
http://taxes.yahoo.com/
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Tefzel Harness for EIS |
>
>
> > >I spoke with Gregg (Grand Rapids Technologies, EIS) today about buying a
> > >tefzel harness for my EIS. He said that he will be offering it in the next
> > >two to three weeks. He's found a supplier that will supply tefzel wire in
> > >many colors.
>
> > Good for you . . . and good for EIS. There's nothing like
> > friendly pressure and good critical review to help our
> > favorite suppliers continue to be our favorite suppliers.
> >
> > Bob . . .
> >
>...and even better for all of us if EIS will name that supplier, and
>said supplier might offer this wire for sale to us airplane-wirin' folk-
>even better yet if supplier offers "kits" with lots of purty colors and
>gauges included! Then toss in assorted fast-ons, tie-wraps, antenna
>cable, shrink-wrap, wire labels etc for the whole shebang- I'll take one
>in XL for MY all-electric air-chariot!
EIS would probably buy from the same kinds of folk that I buy from.
Problem is that 1000' spools of the small stuff is about the minimum
they want to mess with . . . but this could very well be up to the
local office manager. I buy from AE Petsche. They have offices all
over the country. You can find them at:
http://www.aepetsche.com/office.html . . . you don't know until you
ask. This is why I used to (and now B&C) buy 1,000 to 15,000 foot
spools of wire and offer it by the foot from our website . . . colors
are out - it's hard enough to cough up the cash for minimum buys of
one color per gage . . . ten colors per gage is breathtaking unless
you're seeing 10,000 ft/week in sales . . . which of course we're not.
Aircraft Spruce and Wicks sell 22759/16 wire by the foot
at:
http://www.aircraftspruce.com/catmain.php?dest=cathome.html
and
http://www.wicksaircraft.com/gotopage.php?page=127
I just noticed that they stock waxed dacron lacing tape
for a good price at:
http://www.wicksaircraft.com/gotopage.php?page=128
You can find the vast majority of what you'll need in tools and
materials to a good job of wiring your airplane at:
http://www.aeroelectric.com/Catalog/AECcatalog.html
and
http://www.aeroelectric.com/Catalog/BCcatalog.html
and lots of good info on how to apply these materials at:
http://209.134.106.21/articles.html
Aside from major components like alternators, batteries,
radios and instruments, you should be able to do the whole
thing for under $300 . . . maybe less than $200. I'd be
wary of "kits" . . . especially if they're not specifically
tailored to a detailed set of instructions for installation
in YOUR particular airplane. Bundled assortments of wire,
terminals, etc tend to not be of good value because if they
guarantee everything you need, you'll end up with a lot of
surplus. If they don't guarantee everything you need, then
you're going to run short of some items and have to make it
up with multiple orders. If you need to make multiple orders,
you might as well order what you need as you develop the
requirement.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Re: switch wiring |
>
>
>Bob, all
>
>When wiring a switched item is it better to run power to the item
>and switch the ground, or run power to the switch then to the item
>
>Jim Robinson
Come off the bus via circuit protection through the switch and then
to the powered item. Ground with solid wire to either (1)
single point ground on firewall or (2 - if you have a metal
airplane) local grounds for strobes, nav lights, landing/taxi
lights, and pitot heat.
Bob . . .
________________________________________________________________________________
| From: | "Tom Barnes" <skytop(at)megsinet.net> |
| Subject: | Wiring audio panel with audio input |
Bob,
My audio panel accepts only the audio hi from my radios.
The MicroAir 760 output is a shielded pair, hi and lo. Do I simply take
the lo to ground along with the shield?
Thanks in advance.
Tom Barnes
________________________________________________________________________________
| From: | "Tom Barnes" <skytop(at)megsinet.net> |
Jim,
Everything you want to know about this can be found in
AC43.13-1b Par 11-159 page 11-63. Lots of pictures and even specs for
how tight the lacing should be pulled.
Tom Barnes
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jim
Robinson
Subject: AeroElectric-List: RE: wire tying
Does anyone have any info on how the proper way to tie wire
bundles using nylon lacing tape. Is there some trick to this?
Jim Robinson
=
=
=
http://www.matronics.com/browselist/aeroelectric-list
=
________________________________________________________________________________
| From: | Richard RIley <Richard(at)riley.net> |
| Subject: | Re: Tefzel Harness for EIS |
There's a local surplus store with a small mountain of teflon insulated
wire, from 10 gage to 26, randomly available in standard colors and a
rainbow of striped (purple with green, red with yellow, etc,) Also a bunch
of shielded multi conductor, sold by the pound.
Is Teflon insulation acceptable, or should I hold out for tefzel?
>http://209.134.106.21/articles.html
________________________________________________________________________________
| From: | "Paul Messinger" <paulm(at)tenforward.com> |
| Subject: | Re: Tefzel in colors/source |
Pacific Coast Avionics 2001 Catalog(sales 503-678-6242) lists colored Tefzel
wire in 22awg in 10 colors and several years ago, I also got the same
assortment in 20awg. Call to see what is in stock. (also some in 18awg.)
$14 per 100 in 2001 catalog... 50 ft min per color.
My wire was marked MS22759/16/22 12814.
Not super low cost but available!
Paul
________________________________________________________________________________
| Subject: | Re: Wiring from scratch : where do you start ? |
Mike,
Thanks.
> My 2 cents:
>
> Start with two sources: Power and ground
>
> If you are using a ground bus (recommended), it will be directly behind
> the same bus on the engine side of the firewall.
We'll use a ground bus.
Where you have free
> space to mount the ground lug and bus connection on the engine side
> will determine where on the cockpit side your ground bus goes.
Ah, this is a good starting point.
> Once that is determined, you can start putting together wire bundles of
> ground wires from your panel gadgets and run them all to the bus along
> convenient braces, ribs and such. Avoid leaving a spaghetti of wires
> hanging in space behind the panel.
No problem, I've already installed some laced bundles in a previous life ;-)
>
> I am using a main and essential power bus fuse block. I've mounted it
> so that I could swing the fuse block down for maintenance. Where I had
> the space for the swinging mount determined their location behind the
> panel. Then wire power bundles to the fuse blocks.
OK
>
> Now all instrument-to-instrument wiring can be done separately - but
> you have a start with power and ground.
>
>
> The best (and least expensive) way to mark your wires (in my opinion)
> has been mentioned several times and has you use printed labels on
> plain paper rolled around the wire and covered with clear heat shrink.
>
> Print something like:
>
> Master Power
> Master Power
> Master Power
> Master Power
>
Yes. Anyone know of a practical coding method for numbering the wires in a
logical way ?
Thanks again,
Gilles
________________________________________________________________________________
| From: | Garfield Willis <garwillis(at)msn.com> |
| Subject: | Re: Tefzel Harness for EIS |
>Is Teflon insulation acceptable, or should I hold out for tefzel?
Hi Richard, long time etc.,
Teflon sposedly has serious cold-flow problems, which can lead to shorts against
hard cornered objects over long-term. As I understand it, THAT was the prime
reason behind the reformulation that lead to Tefzel, which isn't sposed to have
said problem.
Apocryphal since I don't have a reference to hand, but I thot this was a
commonplace factoid within XA. Please do anyone with more data correct please,
as I'm quite interested in Tefzel, especially if it's now available in many
colors.
Gar
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | RE: Tefzel in colors/source |
>
>
>
>Pacific Coast Avionics 2001 Catalog(sales 503-678-6242) lists colored Tefzel
>wire in 22awg in 10 colors and several years ago, I also got the same
>assortment in 20awg. Call to see what is in stock. (also some in 18awg.)
>
>$14 per 100 in 2001 catalog... 50 ft min per color.
>
>My wire was marked MS22759/16/22 12814.
>
>Not super low cost but available!
>
>Paul
Good data point Paul. Thanks!
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Wiring audio panel with audio input |
>
>Bob,
> My audio panel accepts only the audio hi from my radios.
>The MicroAir 760 output is a shielded pair, hi and lo. Do I simply take
>the lo to ground along with the shield?
>
>Thanks in advance.
Yes . . .
________________________________________________________________________________
| From: | "James K. Glindemann" <jglind(at)netspace.net.au> |
Thank you Bob for the info on tying methods , I have been using the clove
hitch style for many years with great success but have noticed the type 2
method quite a bit on the S76 helicopters I work on and have wondered how it
was done. It would be particularly useful when applying ident tags to
bundles.
We have been using a nomex string with a Boing and mil spec. It is beautiful
stuff to work with, knots do not slip due to the special finish on the
string and although it chars with flame applied to it, it does not support
combustion and does not melt. Makes it especially good for tying things like
thermocouple leads close to exhaust pipes.
I do not have the specicification number with me at the moment but will find
it when I go back to work in a week or so for those who may want it. It
probably won't be cheap to buy.
James K. Glindemann
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | RE: wire tying and AC43.13-1B |
>
>Jim,
> Everything you want to know about this can be found in
>AC43.13-1b Par 11-159 page 11-63. Lots of pictures and even specs for
>how tight the lacing should be pulled.
>
>Tom Barnes
If anyone wants to download the specific pages cited
you can get it from my website archive at . . .
http://209.134.106.21/AC43.13-1B/4b-ch11_12.pdf
if you'd like to download ALL of AC43.13-1B including
the latest update . . .
http://209.134.106.21/AC43.13-1B/AC43.13-1B(1).zip
if you have the original issue of AC43.13-1B and would
like to download only the update try . . .
http://209.134.106.21/AC43.13-1B/AC43.13-1B_update.pdf
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Teflon vs Tefzel Harness |
>
>There's a local surplus store with a small mountain of teflon insulated
>wire, from 10 gage to 26, randomly available in standard colors and a
>rainbow of striped (purple with green, red with yellow, etc,) Also a bunch
>of shielded multi conductor, sold by the pound.
>
>Is Teflon insulation acceptable, or should I hold out for tefzel?
For stuff that stays behind the panel, Teflon is fine. Could
you post the name and address of the store for the benefit of
folks who might avail themselves of it's offering?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Tefzel Harness for EIS |
>
>
> >Is Teflon insulation acceptable, or should I hold out for tefzel?
>
>Hi Richard, long time etc.,
>
>Teflon sposedly has serious cold-flow problems, which can lead to shorts
>against
>hard cornered objects over long-term. As I understand it, THAT was the prime
>reason behind the reformulation that lead to Tefzel, which isn't sposed to
>have
>said problem.
>
>Apocryphal since I don't have a reference to hand, but I thot this was a
>commonplace factoid within XA. Please do anyone with more data correct please,
>as I'm quite interested in Tefzel, especially if it's now available in many
>colors.
Tefzel is the material of choice or something similar like
Raychem's Spec 55 wire. These are not as high a temperature rating
as Teflon but they're tougher. This isn't really an issue behind
the panel and it shouldn't be very much of an issue elsewhere.
After all, ANY insulation is at risk if a wire is allowed to
rest against hard/sharp segments of structure . . . it doesn't
matter what insulation you use, every one will eventually wear
through and compromise the circuit.
We used nothing but Teflon as high temperature lead-wires on all
of Electro-Mech's motor products destined for aircraft installations.
I think they still use a majority of Teflon having deduced that
high temperature characteristics are more important than abrasion
and mechanical stress when your supposed to properly support/protect
the wires from such stress in the first place.
If you can get as good or better deal in Teflon, especially for
cockpit wiring that is well protected, I'd go for it.
Bob . . .
________________________________________________________________________________
| From: | Richard RIley <Richard(at)riley.net> |
| Subject: | Re: Teflon vs Tefzel Harness |
Sure.
Apex Electronics
8909 San Fernando Rd
Sun Valley, CA 91352-1498
Phone: (818)767-7202
`
Very much a rats nest old fashioned aerospace surplus store. Don't know if
they'll do mail order or not.
Legend has it that there's a 49 Ford Pick-up buried under one of the piles
in the yard.
>
>
> >
> >There's a local surplus store with a small mountain of teflon insulated
> >wire, from 10 gage to 26, randomly available in standard colors and a
> >rainbow of striped (purple with green, red with yellow, etc,) Also a bunch
> >of shielded multi conductor, sold by the pound.
> >
> >Is Teflon insulation acceptable, or should I hold out for tefzel?
>
>
> For stuff that stays behind the panel, Teflon is fine. Could
> you post the name and address of the store for the benefit of
> folks who might avail themselves of it's offering?
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Teflon vs Tefzel Harness |
>
>Sure.
>
>Apex Electronics
>8909 San Fernando Rd
>Sun Valley, CA 91352-1498
>Phone: (818)767-7202
>`
>Very much a rats nest old fashioned aerospace surplus store. Don't know if
>they'll do mail order or not.
>
>Legend has it that there's a 49 Ford Pick-up buried under one of the piles
>in the yard.
I remember that place. I was in there a couple
of times when I spent several weeks working a
RAC task in Camarillo. Spent a weekend haunting
the industrial/aviation surplus stores.
I heard it was a '42 pickup.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
>
>
>Thank you Bob for the info on tying methods , I have been using the clove
>hitch style for many years with great success but have noticed the type 2
>method quite a bit on the S76 helicopters I work on and have wondered how it
>was done. It would be particularly useful when applying ident tags to
>bundles.
>
>We have been using a nomex string with a Boing and mil spec. It is beautiful
>stuff to work with, knots do not slip due to the special finish on the
>string and although it chars with flame applied to it, it does not support
>combustion and does not melt. Makes it especially good for tying things like
>thermocouple leads close to exhaust pipes.
>
>I do not have the specicification number with me at the moment but will find
>it when I go back to work in a week or so for those who may want it. It
>probably won't be cheap to buy.
If all someone could buy enough to do their project, say 30-50 yards,
it would probably be reasonable. That kind of stuff tends to come on 500
yard
spools! I've used Nomex sheet as insulation in motors . . . it's
pretty cool stuff if you need that kind of performance.
Bob . . .
________________________________________________________________________________
| Subject: | Wiring two Comm units |
| From: | "Mike Gray" <mgray(at)graymatter.org> |
Bob;
What is the accepted standard -if any- for wiring two COMM trancievers
in an aircraft. The Audio out portion is simple but how do you wire the
mic and PTT switches so as to use the main unit but be able to cross
over to the second unit when required. I would install PTT switches on
both pilot/co-pilot sticks and a simple vox intercom (probably the
intercom inside primary radio - Microair 760SFL-8.33) It would of course
be simple to mount a DPDT switch to clunk one to the other but is there
a more elegant way?
Is there likewise a more practical way of wiring the many RS-232 data
entry devices that are now common. I am talking specifically about
updating the GPS and some of the newer radios that too will allow for
data upload. It would seem that a small USB or Firewire D/A converter
and a little programming on a basic stamp would allow the entire
aircraft system to be accessed (on the ground of course) for updates and
diagnostics. Any thoughts?
Also what is your opinion on using TTL logic and solid state relays to
control such items as Fuel pump, flaps, trim, taxi/landing lights,
strobes etc. In addition to the obvious simplification of stick grip
switching - not to mention the ability to set up pilot side override and
opto-electronic limit switching - This would have the advantage of being
able to fabricate lightweight control heads with LED signalling for the
panel and keeping power runs to a minimum. I am not talking about
multiplexing as in some of the big birds - If Boeing can only get the
switch on your seat to switch on the light three rows ahead then we are
all in trouble!
I understand some of this goes against your KISS principles however we
are seeing a sea change in avionics and this is causing a rethink of
some of the basics..
Mike Gray
________________________________________________________________________________
| From: | "Rob W M Shipley" <Rob(at)RobsGlass.com> |
| Subject: | Wag Waero / ICS Radio |
This radio on P. 16 of the current catalogue seems to offer a lot for
the money, (although somewhat heavy). Does anyone have any experience
of these radios?
Rob
Rob W M Shipley. Rob(at)RobsGlass.com
RV9A fuse ordered.
________________________________________________________________________________
| From: | "Richard D. Fogerson" <rickf(at)velocitus.net> |
| Subject: | Wire AWG and Fusible Links |
Hi Bob,
Just to clear up a few things that are nagging at me from the list. I
plan an RV3 with 40A and SD8 alternators, dual E.I.'S, 12 AHr battery
(if I can find) behind seat, and Z13 architecture.
Re alternator feeds: There was a recent discussion about an RV8 with
the battery in frount Vs the back. A 12AWG alternator feed and a 20AWG
fusible link were recommended with battery in back. What wires does
"alternator feeds" constitute and does this apply to both alternators?
I notice on Z13 that 12AWG is used on SD8 but 18AWG is used on the
40A so does this only apply to SD8?
Re fusible links and the E.I.'s: You've stated that one justification
for fusible links is they are more reliable/longer lived than fuse
blocks. All that would be on a battery bus is the hobbs and the two
E.I.'s. Would you recommend eliminating the bus and just using 22AWG
fusible links and 18AWG wire for these three items?
Re contactor location: With the battery in back, a lister stated that
the battery contactor needed to be in back also. But Z13 only specifies
that the battery contactor be within 6 inches of the battery bus (or
presumably the fusible links to the E.I.'s and the hobbs if no bat bus).
There is nothing about how close the battery is to the contactor. I
conclude that the battery contactor should be on the firewall and not
next to the battery. Is this correct?
Re cheap Vs expensive batteries: On the list there are enthusiastic
proponents of both (e.g. the $30 garden tractor Vs the $74 Odysey). I
think I've seen you say there's nothing wrong with the cheap one. As a
practical matter wouldn't you be inclined to change out the cheap one
twice as often, say each year, as the Odysey, every 2 years?
Thank you so much for your help and patience with my dumb questions.
Rick Fogerson
RV3 fuselage
Boise, ID
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Wire size, Fusible Links and battery choices. |
>
>
>Hi Bob,
>Just to clear up a few things that are nagging at me from the list. I
>plan an RV3 with 40A and SD8 alternators, dual E.I.'S, 12 AHr battery
>(if I can find) behind seat, and Z13 architecture.
Good choice. Make the battery decision last. An RG battery
needs only a shallow tray to capture the footprint and a
holddown strap(s) capable of 200+ pounds tensile strenght.
A couple of velcro straps with 6" or more overlap will
exceed this by a large margin.
>Re alternator feeds: There was a recent discussion about an RV8 with
>the battery in frount Vs the back. A 12AWG alternator feed and a 20AWG
>fusible link were recommended with battery in back. What wires does
>"alternator feeds" constitute and does this apply to both alternators?
>I notice on Z13 that 12AWG is used on SD8 but 18AWG is used on the
>40A so does this only apply to SD8?
Each alternator has it's own situation with respect to system
interface and performance as it relates to wires sizes and
lengths. The SD-8 is an 8A rated, 10A capable machine. It
should be attached to the system with protection rated at no
less than 10A continuous duty operation. If lead lengths
are short, 16AWG wire would suffice. Since the regulator should
be close to the alternator -AND- because the regulator senses
bus voltage through the same leadwire that delivers power to
the system, I like to control voltage drop along this wire when
the battery is located some distance from the regulator as
in the situation you are considering. This is why I show
heavier, 12AWG wire. This selection dates back to the earliest
days of popular use of the SD-8 . . . long and vari-eze airplanes
with alternator in tail, battery up front and both power and ground
wires bringing power to the front with as much as 25-30' round
trip. PROTECTION of this wire can still be rated as if it
were used in a tractor aircraft with battery up front . . .
16AWG and 20AWG fuselink works if you're interested in
taking advantage of what the fuselink offers. This could
be a 10A fuse or breaker as well.
>Re fusible links and the E.I.'s: You've stated that one justification
>for fusible links is they are more reliable/longer lived than fuse
>blocks. All that would be on a battery bus is the hobbs and the two
>E.I.'s. Would you recommend eliminating the bus and just using 22AWG
>fusible links and 18AWG wire for these three items?
This is an option but it makes you stack a lot of terminals
on a single stud but if they all fit on the hot-side stud
of your battery contactor, you can do this. I had one builder
worrying about the single feedline between contactor and
battery bus fuse block as being single point of failure for
both ignitions. True but relatively easy to build the same
reliability for this short piece of wire as say, the attachement
of wings to the fuselage. I think he ended up putting a fuse-link
feed on one ignition and then running all the rest of the battery
bus items from the fuse block . . . a good example of actions
taken in consideration of risk and physics as opposed to worship
at the altar of hangar tales and wizened ol' salts who assure
you that, "you'd better stick to the way we've always done it
no matter what you think."
>Re contactor location: With the battery in back, a lister stated that
>the battery contactor needed to be in back also. But Z13 only specifies
>that the battery contactor be within 6 inches of the battery bus (or
>presumably the fusible links to the E.I.'s and the hobbs if no bat bus).
> There is nothing about how close the battery is to the contactor. I
>conclude that the battery contactor should be on the firewall and not
>next to the battery. Is this correct?
I should mark those leads with (*) too . . . I think I mention it in
the text of the book. Battery contactors need to be located as
close as practical to the battery and the battery, bus if you
have one, should be as close as practical to the contactor.
>Re cheap Vs expensive batteries: On the list there are enthusiastic
>proponents of both (e.g. the $30 garden tractor Vs the $74 Odysey). I
>think I've seen you say there's nothing wrong with the cheap one. As a
>practical matter wouldn't you be inclined to change out the cheap one
>twice as often, say each year, as the Odysey, every 2 years?
Sure. And what's the risk of trying the cheapest battery you
can lay your hands on? As long as I'm dealing with RG
technology I'd buy a cheapie and test it at the end of a
year. If it has performed well for the past year and still
presents an acceptable capacity, hey . . . the cheapie is
a good deal. If not, then upgrade.
I see a lot of builders agonizing over battery choices like
they would for an STC on a certified ship. Make the wrong choice
here man and you're stuck with a certified error carved into
stone. In homebuilts we're free to TRY anything for which
we've considered and mitigated risks and determine which
products are suited to the way we use our airplanes.
Leave enough room for a 24 a.h. footprint for your battery tray.
Start out with the cheapest battery you can lay your hands on
in an RG technology. If you don't like it, making a new tray
to fit a different battery is no big deal.
>Thank you so much for your help and patience with my dumb questions.
No problem.
Bob . . .
________________________________________________________________________________
| From: | "Gary M. Plewa" <gplewa(at)esp.telcordia.com> |
| Subject: | "idiot light" wiring for a Delco Shunt wound generator |
Does anyone know how to wire a generator warning light on a
Delco shunt wound generator with a three terminal (Bat, Arm, Field)
mechanical regulator? This is on Continental E series engine if
that has any bearing on the type involved. I have an Ammeter on
the panel but would like to have a warning annunciator too.
Thanks,
Gary
________________________________________________________________________________
| From: | "Piers Herbert" <piers.herbert(at)ntlworld.com> |
| Subject: | Re: "idiot light" wiring for a Delco Shunt wound generator |
> Does anyone know how to wire a generator warning light on a
> Delco shunt wound generator with a three terminal (Bat, Arm, Field)
> mechanical regulator? This is on Continental E series engine if
> that has any bearing on the type involved. I have an Ammeter on
> the panel but would like to have a warning annunciator too.
> Thanks,
> Gary
I think I would have a light that comes on at >13.0 volts on the bus, i.e.
keep the warning circuit independant of the generator.
Piers
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Wiring two Comm units |
>
>Bob;
>
>What is the accepted standard -if any- for wiring two COMM trancievers
>in an aircraft. The Audio out portion is simple but how do you wire the
>mic and PTT switches so as to use the main unit but be able to cross
>over to the second unit when required. I would install PTT switches on
>both pilot/co-pilot sticks and a simple vox intercom (probably the
>intercom inside primary radio - Microair 760SFL-8.33) It would of course
>be simple to mount a DPDT switch to clunk one to the other but is there
>a more elegant way?
Don't think so. That's the way it's been done since the
first airplane received it's second radio. I wired a Cessna
with three transmitters using a 4-pole version of our
S700-2-10 switch in a miniature version. Placing jumpers
in proper places on the back of the switch gave me a
three position, miniature toggle that would move the
microphone to the desired transmitter. The transmitter
select switch of most audio panels does this same thing
albeit with a rotary device as opposed to a toggle.
>Is there likewise a more practical way of wiring the many RS-232 data
>entry devices that are now common. I am talking specifically about
>updating the GPS and some of the newer radios that too will allow for
>data upload. It would seem that a small USB or Firewire D/A converter
>and a little programming on a basic stamp would allow the entire
>aircraft system to be accessed (on the ground of course) for updates and
>diagnostics. Any thoughts?
RS232 is a host-to-client protocol . . . if you're interested a
one bus does all tasks for all systems, you need a party-line
bus like CAN, Mil-Std-1553, RS-485, etc. We've dreamed about
this for years and it's now quite possible . . . all we need to
do is get all interested parties to talk and adopt standards.
RISK: a new bureaucracy grows out of the effort that could
inhibit innovation. One must proceed with caution.
>Also what is your opinion on using TTL logic and solid state relays to
>control such items as Fuel pump, flaps, trim, taxi/landing lights,
>strobes etc. In addition to the obvious simplification of stick grip
>switching - not to mention the ability to set up pilot side override and
>opto-electronic limit switching - This would have the advantage of being
>able to fabricate lightweight control heads with LED signalling for the
>panel and keeping power runs to a minimum. I am not talking about
>multiplexing as in some of the big birds - If Boeing can only get the
>switch on your seat to switch on the light three rows ahead then we are
>all in trouble!
>
>I understand some of this goes against your KISS principles however we
>are seeing a sea change in avionics and this is causing a rethink of
>some of the basics..
Understand . . . and agree if the advantage is an increase in
value as opposed to a reverence for doing it just because it can
be done and we couldn't do it a few years ago.
For example, a gentleman I know had a demo at OSH about 5 years
ago wherein he showed how we can "control everything on this
low cost data bus". You still had an on-off switch. You still
needed a protected source of power (breaker or fuse on a bus), you
still had an appliance that need to be controlled at the
pleasure of the pilot. The only thing that the technique did was
replace a few pieces of wire with LOTS of transistors and other
components . . . I was having a hard time deducing any increase in
value.
Another example: FADEC . . . we've had a number of fly-by-wire
projects at RAC including FADECs . . . in most cases, complexity
of the systems went up in terms of transistors and software while
the systems got simpler mechanically . . . but dealing
with failure modes became the driving factors with respect to cost
of certification, manufacture and ownership . . . a really tough
thing to demonstrate as an increase in value (doing the same job
equal to or better than before at less cost and without hurting
reliability).
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: "idiot light" wiring for a Delco Shunt wound generator |
>
>
>Does anyone know how to wire a generator warning light on a
>Delco shunt wound generator with a three terminal (Bat, Arm, Field)
>mechanical regulator? This is on Continental E series engine if
>that has any bearing on the type involved. I have an Ammeter on
>the panel but would like to have a warning annunciator too.
>Thanks,
>Gary
Make your warning light totally independent of the power
generating source. You need a light that flashes any time
the bus drops below 13.0 volts irrespective of whether
your source is generator or alternator. You can brew your
own per:
http://209.134.106.21/articles/lvwarn/9021-610.pdf
. . . or get one of these when they pop up on the website
in a few days . . .
http://209.134.106.21/temp/MVC-081X.JPG
http://209.134.106.21/temp/MVC-082X.JPG
or build one from your own acquisition of parts using a
bare etched circuit board and instructions that will be
made available as a partial kit.
The warning lights associated with virtually every alternator
or generator installation will NOT annunciate all system failure
modes . . . the low volts warning light WILL.
Bob . . .
________________________________________________________________________________
| From: | lhdodge1(at)mmm.com |
22, 2000) at 04/08/2002 12:52:59 PM
Thanks for the reply regarding the use of Digikey W28 series Circuit
Breakers. I got a kick from your reply regarding me "playing airborne
systems analyst and repair person". Actually, I have read your materials
regarding auto style fuses vs. circuit breakers and understand where you
are coming from.
My choice of using C/Bs is for the following reasons:
1. I want to be able to turn off individual circuits.
2. I want to be able to easily see that a circuit has tripped.
3. The small C/Bs I mentioned earlier fit my panel and I like the way they
look (personal ).
4. The auto style fuses are hard to get out (at least with my fingers).
5. I can't find an economical single row fuse block that holds more than
six fuses.
6. The C/Bs I was asking about are less costly than fuses with block.
Regards,
Larry Dodge
lhdodge1(at)mmm.com
________________________________________________________________________________
| Subject: | Unable to open Wirebook |
Bob,
Maybe I'm missing the obvious, but to date I've been unable to open your
wirebook.exe file. I'm getting a "PKZip error" in a DOS window.
Autocad 14 is installed on my computer, but I'm not an expert. So is there
something I've been doing wrong ?
Thank you
Gilles
________________________________________________________________________________
| Subject: | Electronics for LED fuel gauge |
Hi, Bob and all,
Does anyone know what electronics is in involved in using off-the-shelf LED
bargraphs for fuel gauges. Our senders are 240/33 ohms empty to full.
Thanks
Gilles
________________________________________________________________________________
| Subject: | Re: C/B question + |
| From: | <racker(at)rmci.net> |
>
> 6. The C/Bs I was asking about are less costly than fuses with block.
W28:
$2.64 per circuit times 10 devices = $26.40
Fuseblocks:
$16.95 10-position fuseblock plus $3.80 fuses = $20.75
Rob Acker (RV-6).
________________________________________________________________________________
| From: | "Matthew Mucker" <matthew(at)mucker.net> |
| Subject: | Electronics for LED fuel gauge |
In discrete circuitry, you're probably looking at resistance-to-voltage
conversion and then 10 comparators feeding the LEDs.
Ick!
Using a microcontroller you could do resistance-to-voltage and find a uP
with A/D conversion built in. Development costs would be high, but the OTP
(one time programmable) versions of the microcontrollers are surprisingly
affordable, even in onesies. A PIC microcontroller (www.microchip.com)
could handle this with ease.
However, I fear that the cost/benefit ratio to roll your own one-off gizmo
is probably above your threshhold. :)
-Matt
> Does anyone know what electronics is in involved in using
> off-the-shelf LED
> bargraphs for fuel gauges. Our senders are 240/33 ohms empty to full.
________________________________________________________________________________
| Subject: | Re: Wiring two Comm units |
Robert L. Nuckolls, III wrote:
>
> >Is there likewise a more practical way of wiring the many RS-232 data
> >entry devices that are now common. I am talking specifically about
> >updating the GPS and some of the newer radios that too will allow for
> >data upload. It would seem that a small USB or Firewire D/A converter
> >and a little programming on a basic stamp would allow the entire
> >aircraft system to be accessed (on the ground of course) for updates and
> >diagnostics. Any thoughts?
>
> RS232 is a host-to-client protocol . . . if you're interested a
> one bus does all tasks for all systems, you need a party-line
> bus like CAN, Mil-Std-1553, RS-485, etc.
*** How about Ethernet? The technology is now dirt cheap, the speed &
bandwidth are ample. Yes, it's just best-effort delivery, but higher-level
protocols take care of that.
In fact, TCP/IP ( which runs over Ethernet, et al ) was originally
designed with military goals ( funded by DARPA ). If a switching center is
taken out, IP routers automatically route the traffic around it. One could
design a system with two ethernet ports on every "important" item, and use
MLT ( multi-link-trunking ) to provide automatic and nearly instant
redundancy.
- Jerry Kaidor ( jerry(at)tr2.com )
________________________________________________________________________________
| From: | SportAV8R(at)aol.com |
| Subject: | Re: Electronics for LED fuel gauge |
In a message dated 04/08/2002 3:33:08 PM Eastern Daylight Time,
matthew(at)mucker.net writes:
> In discrete circuitry, you're probably looking at resistance-to-voltage
> conversion and then 10 comparators feeding the LEDs.
>
> Ick!
>
>
Actually nothing icky about it; I built such a circuit years ago and it
worked great. Now that I am into airplanes, I can't recall the recipe and
cannot find it in the Radio Shack/Forrest Mimms books where it first came to
my attention. Drat! Now my plane is finished and flying for several years
with steam gauges for the fuel -- double-drat. If someone knows the discrete
components needed for such a circuit, I'd be interested.
-Bill B RV-6A
________________________________________________________________________________
| From: | mprather(at)spro.net |
| Subject: | Re: Electronics for LED fuel gauge |
How about this?
In a conventional gauge (a float moves a variable resistor), make
the output of the sender drive the inputs of a network of discrete
comapators (LM339). Make the other inputs to the comparators driven
by an array of voltage dividers which cover the range between the
minimum output voltage of the sender to the maximum voltage from the
sender. At low fuel, the resistance of the sender is high, making
its output low which means only the LED with the minimum reference
is lit. At full fuel, the sender has low resistance, causing the
output to go up which will mean that all of the LED's will be lit.
It wouldn't be temperature compensated, but it would be simple to
build and test.
Not sure how the capacitive gauges work, but if its the same kind
of thing where the gain of a circuit is controlled by the capacitance
of the fuel, then the same kind of comparator- LED drive scheme would
work.
Regards,
Matt Prather
Varieze N34RD
----- Original Message -----
From: "Matthew Mucker" <matthew(at)mucker.net>
Date: Monday, April 8, 2002 1:31 pm
Subject: RE: AeroElectric-List: Electronics for LED fuel gauge
>
> In discrete circuitry, you're probably looking at resistance-to-
> voltageconversion and then 10 comparators feeding the LEDs.
>
> Ick!
>
> Using a microcontroller you could do resistance-to-voltage and find
> a uP
> with A/D conversion built in. Development costs would be high, but
> the OTP
> (one time programmable) versions of the microcontrollers are
> surprisinglyaffordable, even in onesies. A PIC microcontroller
> (www.microchip.com)could handle this with ease.
>
> However, I fear that the cost/benefit ratio to roll your own one-
> off gizmo
> is probably above your threshhold. :)
>
> -Matt
>
> > Does anyone know what electronics is in involved in using
> > off-the-shelf LED
> > bargraphs for fuel gauges. Our senders are 240/33 ohms empty to
> full.
>
> _-
>
- The AeroElectric-List Email Forum -
> _-
>
!! NEW !!
> _-
>
List Related Information
> _-
>
=======================================================================
>
>
>
>
>
________________________________________________________________________________
| Subject: | Re: Electronics for LED fuel gauge |
SportAV8R(at)aol.com wrote:
>
>
>
> > In discrete circuitry, you're probably looking at resistance-to-voltage
> > conversion and then 10 comparators feeding the LEDs.
> >
> > Ick!
> >
> >
>
> Actually nothing icky about it; I built such a circuit years ago and it
> worked great. Now that I am into airplanes, I can't recall the recipe and
> cannot find it in the Radio Shack/
**** Now I seem to remember RS carrying a bar graph driver chip. Analog
voltage goes in one end, and the individual bar drivers come out the other
end.
A quick web search reveals - ta-daaa! The National LM3914 bar graph
driver chip. Couldn't be simpler.
- Jerry Kaidor ( jerry(at)tr2.com )
________________________________________________________________________________
| From: | "Matthew Mucker" <matthew(at)mucker.net> |
| Subject: | Electronics for LED fuel gauge |
I think Jerry wins the prize here. Now all we need is a resistance to
voltage converter, and I think Jim Weir covered this in a recent
Aero'Lectrics column in Kitplanes when he describes how to use the Radio
Shack meter to display everything.
> **** Now I seem to remember RS carrying a bar graph driver chip. Analog
> voltage goes in one end, and the individual bar drivers come out the other
> end.
>
>
> A quick web search reveals - ta-daaa! The National LM3914 bar graph
> driver chip. Couldn't be simpler.
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Electronics for LED fuel gauge |
>
>
>**** Now I seem to remember RS carrying a bar graph driver chip. Analog
>voltage goes in one end, and the individual bar drivers come out the other
>end.
>
>
> A quick web search reveals - ta-daaa! The National LM3914 bar graph
>driver chip. Couldn't be simpler.
>
> - Jerry Kaidor ( jerry(at)tr2.com )
You beat me to it Jerry.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Wiring two Comm units |
> > >Is there likewise a more practical way of wiring the many RS-232 data
> > >entry devices that are now common. I am talking specifically about
> > >updating the GPS and some of the newer radios that too will allow for
> > >data upload. It would seem that a small USB or Firewire D/A converter
> > >and a little programming on a basic stamp would allow the entire
> > >aircraft system to be accessed (on the ground of course) for updates and
> > >diagnostics. Any thoughts?
> >
> > RS232 is a host-to-client protocol . . . if you're interested a
> > one bus does all tasks for all systems, you need a party-line
> > bus like CAN, Mil-Std-1553, RS-485, etc.
>
>*** How about Ethernet? The technology is now dirt cheap, the speed &
>bandwidth are ample. Yes, it's just best-effort delivery, but higher-level
>protocols take care of that.
>
> In fact, TCP/IP ( which runs over Ethernet, et al ) was originally
>designed with military goals ( funded by DARPA ). If a switching center is
>taken out, IP routers automatically route the traffic around it. One could
>design a system with two ethernet ports on every "important" item, and use
>MLT ( multi-link-trunking ) to provide automatic and nearly instant
>redundancy.
Sure . . . there are a number of bus structures capable of doing
about any level of communications necessary. My approach would be
to first decided what kind of things really NEED to be communicated
from place to place in the airplane and do they justify the minimum
requirement for bus transceiver and interface electronics to make
it happen. With one-box-does-it-all products like the Garmin 530
and the fact that our itty-bitty airplanes need so few devices for
very precise navigation and control - I don't see any big fires for
data busses to fight.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: C/B question + |
>
> >
> > 6. The C/Bs I was asking about are less costly than fuses with block.
>
>
>W28:
>$2.64 per circuit times 10 devices = $26.40
>
>Fuseblocks:
>$16.95 10-position fuseblock plus $3.80 fuses = $20.75
If you're happy with 'em, what can I say? I don't
think the selection of any particular breaker represents
a potential for hazard. This presumes that you've
architectured your system so that loss of any system
powered through a breaker (or fuse - it doesn't matter)
is not a precursor for hazard. You're therefor free to give
'em a try and put in something else if they fall short
of your expectations.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: C/B question + |
>
>Thanks for the reply regarding the use of Digikey W28 series Circuit
>Breakers. I got a kick from your reply regarding me "playing airborne
>systems analyst and repair person". Actually, I have read your materials
>regarding auto style fuses vs. circuit breakers and understand where you
>are coming from.
>
>My choice of using C/Bs is for the following reasons:
>
>1. I want to be able to turn off individual circuits.
>2. I want to be able to easily see that a circuit has tripped.
>3. The small C/Bs I mentioned earlier fit my panel and I like the way they
>look (personal ).
>4. The auto style fuses are hard to get out (at least with my fingers).
>5. I can't find an economical single row fuse block that holds more than
>six fuses.
>6. The C/Bs I was asking about are less costly than fuses with block.
I understand the reasons and if that's what you want,
then who are we to dissuade you from achieving
those desires? If you've found arguments in favor
of other philosophies unconvincing, it's my expectation
that this airplane is going to perform in accordance with
your own philosophy . . . and that's fine too.
Bob . . .
________________________________________________________________________________
| From: | "Matthew Mucker" <matthew(at)mucker.net> |
| Subject: | Re: Wiring two Comm units |
>
> Sure . . . there are a number of bus structures capable of doing
> about any level of communications necessary. My approach would be
> to first decided what kind of things really NEED to be communicated
> from place to place in the airplane and do they justify the minimum
> requirement for bus transceiver and interface electronics to make
> it happen. With one-box-does-it-all products like the Garmin 530
> and the fact that our itty-bitty airplanes need so few devices for
> very precise navigation and control - I don't see any big fires for
> data busses to fight.
>
> Bob . . .
>
I tend to take the opposite approach. If we limit bandwidth to what is
NEEDED, there's zero room for future expandability. With so many
inexpensive, high bandwidth protocols, I think it would make more sense to
choose a bus with plenty of headroom into which future data can be placed.
Look at the USB spec: by the time it was finally delivered to the
marketplace, there were devices that people WANTED to put on USB but
couldn't because it was already bandwidth limited. I can't imagine what
else we'd want to put on such a bus, but that's precisely the reason extra
headroom should be built in. :)
Two different approaches to the problem, I guess.
-Matt
________________________________________________________________________________
| Subject: | Re: Electronics for LED fuel gauge |
Matthew Mucker wrote:
>
>
> I think Jerry wins the prize here. Now all we need is a resistance to
> voltage converter,
*** Simple. Just drive the resistor with a constant current source. This
can be simulated with another resistor, several times larger than the
highest value of the resistance to be measured, going to +12V. Ten times
larger is probably OK. 100 times larger would be even more linear, but your
voltage-to-measure would then be pretty small.
You can also construct an extremely accurate current source out of a
three-terminal regulator - but it will need a certain amount of head room.
- Jerry
> Aero'Lectrics column in Kitplanes when he describes how to use the Radio
> Shack meter to display everything.
>
> > **** Now I seem to remember RS carrying a bar graph driver chip. Analog
> > voltage goes in one end, and the individual bar drivers come out the other
> > end.
> >
> >
> > A quick web search reveals - ta-daaa! The National LM3914 bar graph
> > driver chip. Couldn't be simpler.
> >
>
>
>
>
>
>
________________________________________________________________________________
| From: | Finn Lassen <finnlassen(at)netzero.net> |
| Subject: | Re: Electronics for LED fuel gauge |
A single chip is all it takes: LM3914 or LM3915 and a couple of external
resistors.
However, I don't know that the sender is linear, and if not, if you're lucky
enough to have the LM3915 (logarithmic) match the curve.
Might be worth a try: it's cheap and easy (just the chip, a 10-LED bar or 10
individual LEDs, and a piece of breadboard).
RadioShack on-line used to carry these, don't know of they still do.
Finn
Matthew Mucker wrote:
>
> In discrete circuitry, you're probably looking at resistance-to-voltage
> conversion and then 10 comparators feeding the LEDs.
>
> Ick!
>
> Using a microcontroller you could do resistance-to-voltage and find a uP
> with A/D conversion built in. Development costs would be high, but the OTP
> (one time programmable) versions of the microcontrollers are surprisingly
> affordable, even in onesies. A PIC microcontroller (www.microchip.com)
> could handle this with ease.
>
> However, I fear that the cost/benefit ratio to roll your own one-off gizmo
> is probably above your threshhold. :)
>
> -Matt
>
> > Does anyone know what electronics is in involved in using
> > off-the-shelf LED
> > bargraphs for fuel gauges. Our senders are 240/33 ohms empty to full.
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Unable to open Wirebook |
><Gilles.Thesee@ac-grenoble.fr>
>
>
>Bob,
>
>Maybe I'm missing the obvious, but to date I've been unable to open your
>wirebook.exe file. I'm getting a "PKZip error" in a DOS window.
>Autocad 14 is installed on my computer, but I'm not an expert. So is there
>something I've been doing wrong ?
>
>Thank you
I am mystified. Wirebook.exe is a self extracting pkzip file that
should unfold into a half dozen or so drawings. I really need to
update that file . . . the foldout drawings are from about Rev
7 of the book.
I've updated wirebook.exe and re-compiled it. Try downloading
again. Also get seminar.exe and see if it behaves any differently.
Put these files into their own empty directory before you call them.
They unfold into lots of files that might get lost in the forest
if there are other files in the directory before you open them.
http://209.134.106.21/articles/seminar.exe
http://209.134.106.21/articles/wirebook.exe
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | RE: to bus or not to bus . . . that IS the question. |
>
> >
> > Sure . . . there are a number of bus structures capable of doing
> > about any level of communications necessary. My approach would be
> > to first decided what kind of things really NEED to be communicated
> > from place to place in the airplane and do they justify the minimum
> > requirement for bus transceiver and interface electronics to make
> > it happen. With one-box-does-it-all products like the Garmin 530
> > and the fact that our itty-bitty airplanes need so few devices for
> > very precise navigation and control - I don't see any big fires for
> > data busses to fight.
> >
> > Bob . . .
> >
>
>I tend to take the opposite approach. If we limit bandwidth to what is
>NEEDED, there's zero room for future expandability. With so many
>inexpensive, high bandwidth protocols, I think it would make more sense to
>choose a bus with plenty of headroom into which future data can be placed.
>Look at the USB spec: by the time it was finally delivered to the
>marketplace, there were devices that people WANTED to put on USB but
>couldn't because it was already bandwidth limited. I can't imagine what
>else we'd want to put on such a bus, but that's precisely the reason extra
>headroom should be built in. :)
>
>Two different approaches to the problem, I guess.
My perception of NEED wasn't couched in terms of bus capability
but in the need to tie things together with high speed data
busses in the first place.
I see this done all the time in the bizjets but not one piece
of that hardware would be attractive to me in a single engine
light plane. If I could sit down with my magic wand and cause
my fondest dreams for SE cockpit hardware to come into being,
I don't see how there would be much need for everyone to talk/listen
to everyone else on high speed data busses. We hear and see the
big fellers doing it but I'm not feeling left out because
the hardware I'd like to have won't need data bussing.
Bob . . .
________________________________________________________________________________
| From: | Villi Seemann <villi.seemann(at)nordea.com> |
| Subject: | Re: AeroElectric-List Digest: 25 Msgs - 04/08/02 |
somebody asked
> Does anyone know what electronics is in involved in using
> off-the-shelf LED
> bargraphs for fuel gauges. Our senders are 240/33 ohms empty to full.
the cheapest/easyest way is using a pair of LM3914 bar-graph display
drivers from Nat.Semi
Regards
Villi H. Seemann
Senior Engineer
Infrastructure Network
Phone (+45) 3333 2101
FAX (+45) 3333 1130
CellPhn (+45)2220 7690
________________________________________________________________________________
| Subject: | Re: Unable to open Wirebook |
> I am mystified. Wirebook.exe is a self extracting pkzip file that
> should unfold into a half dozen or so drawings. I really need to
> update that file . . . the foldout drawings are from about Rev
> 7 of the book.
>
> I've updated wirebook.exe and re-compiled it. Try downloading
> again. Also get seminar.exe and see if it behaves any differently.
> Put these files into their own empty directory before you call them.
> They unfold into lots of files that might get lost in the forest
> if there are other files in the directory before you open them.
>
> http://209.134.106.21/articles/seminar.exe
>
> http://209.134.106.21/articles/wirebook.exe
>
Bob,
Thanks, but...tried everyting you said, disabled the antivirus app, but I'm
still getting the same "error in zip use PKZipFix" message. The directories
remain hopelessly empty except for that unexecutable dot exe file ! Wonder
where this PKZipFix can be get from.
Is there a URL where I can get those programs in a non-zipped form ?
Thank you,
Gilles
________________________________________________________________________________
| Subject: | Electronics for LED fuel gauge |
Bob, Bill, Finn, Jerry, Matt and all
Thank you for your replies. I'm no electronic techie but I can solder
and"understand" what's going on in the system. All I have to do now is
order, and make some breadboard prototype.
But bolting on an off-the-shelf gauge is so much easier...
Cheers,
Gilles
Finn Lassen
>
> A single chip is all it takes: LM3914 or LM3915 and a couple of external
> resistors.
>
> However, I don't know that the sender is linear, and if not, if you're
lucky
> enough to have the LM3915 (logarithmic) match the curve.
>
> Might be worth a try: it's cheap and easy (just the chip, a 10-LED bar or
10
> individual LEDs, and a piece of breadboard).
>
> RadioShack on-line used to carry these, don't know of they still do.
>
> Finn
>
> Matthew Mucker wrote:
>
> >
> > In discrete circuitry, you're probably looking at resistance-to-voltage
> > conversion and then 10 comparators feeding the LEDs.
> >
> > Ick!
> >
> > Using a microcontroller you could do resistance-to-voltage and find a uP
> > with A/D conversion built in. Development costs would be high, but the
OTP
> > (one time programmable) versions of the microcontrollers are
surprisingly
> > affordable, even in onesies. A PIC microcontroller (www.microchip.com)
> > could handle this with ease.
> >
> > However, I fear that the cost/benefit ratio to roll your own one-off
gizmo
> > is probably above your threshhold. :)
> >
> > -Matt
________________________________________________________________________________
| From: | Glenn Rainey <nimbusaviation(at)yahoo.com> |
Bob, folks - some time ago I asked about light-weight
battery contactors and was pointed in the direction of
using a switch - perhaps cable operated.
Can you suggest any actual device / source? Am trying
to get my orders lined up for collection stateside
July / Osh.
keep up the good work
Glenn Rainey
Long-EZ, Scotland UK
http://taxes.yahoo.com/
________________________________________________________________________________
| From: | SportAV8R(at)aol.com |
| Subject: | Re: Electronics for LED fuel gauge |
In a message dated 04/09/2002 5:57:57 AM Eastern Daylight Time,
Gilles.Thesee@ac-grenoble.fr writes:
> Bob, Bill, Finn, Jerry, Matt and all
>
> Thank you for your replies. I'm no electronic techie but I can solder
> and"understand" what's going on in the system. All I have to do now is
> order, and make some breadboard prototype.
> But bolting on an off-the-shelf gauge is so much easier...
>
> Cheers,
>
> Gilles
>
Agreed; still, wouldn't it be nice if Bob would jot down a schematic and post
it for downloading as an Adobe file or something :-)
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: battery switch |
>
>
>Bob, folks - some time ago I asked about light-weight
>battery contactors and was pointed in the direction of
>using a switch - perhaps cable operated.
>
>Can you suggest any actual device / source? Am trying
>to get my orders lined up for collection stateside
>July / Osh.
No particular switch comes to mind. I had several
builders go the manual battery switch over the years.
I believe all of them found a suitable device at
either (1) a marine electrical supply or (2)
performance automotive supply. Many boats with
multiple battery installations use manually operated
heavy duty switches to select which battery is
in service. Raceways for cars often require a battery
disconnect switch be readily available to fire/rescue
crews.
I'm fairly certain you could find one locally. Here
an example on the 'net . . .
http://www.boatus-store.com/browse/item.asp?IID=17020
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Unable to open Wirebook |
><Gilles.Thesee@ac-grenoble.fr>
>
> > I am mystified. Wirebook.exe is a self extracting pkzip file that
> > should unfold into a half dozen or so drawings. I really need to
> > update that file . . . the foldout drawings are from about Rev
> > 7 of the book.
> >
> > I've updated wirebook.exe and re-compiled it. Try downloading
> > again. Also get seminar.exe and see if it behaves any differently.
> > Put these files into their own empty directory before you call them.
> > They unfold into lots of files that might get lost in the forest
> > if there are other files in the directory before you open them.
> >
> > http://209.134.106.21/articles/seminar.exe
> >
> > http://209.134.106.21/articles/wirebook.exe
> >
>
>Bob,
>
>Thanks, but...tried everyting you said, disabled the antivirus app, but I'm
>still getting the same "error in zip use PKZipFix" message. The directories
>remain hopelessly empty except for that unexecutable dot exe file ! Wonder
>where this PKZipFix can be get from.
>Is there a URL where I can get those programs in a non-zipped form ?
I could try e-mailing them directly to you . . . there's a bunch.
Do you have PKzip on your computer? What version? If it's a windows
version, it will have a PKzipFix utility built in. See:
http://www.pkware.com/support/faq/?topic=zipg#q3
If you want, I'll try to e-mail the batch . . .
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Fwd: Brass strips |
Bob
I have CB's on my panel and I ordered the brass strips from B&C. I
have a question about the size of the strips. They are .5 " wide
and overhang the CB tabs a lot. They are about .25 wide. Would it
be electrically OK to cut the strips in half (.25 wide)?
We need the cross section of brass to carry full
capability of the alternator. Certified ships generally
have bus bars that are "too wide" . . . they often
drill the row of holes off-center to the strip's
long axis to have excess metal extend inboard of the
breaker's profile.
Bob . . .
--------------------------------------------
| People are far more willing to pay |
| for being amused than for anything else. |
| -Thomas Edison- |
--------------------------------------------
________________________________________________________________________________
| From: | "Ned Thomas" <nthomas(at)mmcable.com> |
| Subject: | Re: battery switch |
Here is a couple of battery disconnect switches that can be had with a lever
to actuate from the cockpit.
http://store.summitracing.com/default.asp?target=%2Fsection%2Easp%3Fd%3D11%2
6s%3D14
http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=7165&prmenbr=7
6
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckolls(at)kscable.com>
Subject: AeroElectric-List: Re: battery switch
>
> >
> >
> >Bob, folks - some time ago I asked about light-weight
> >battery contactors and was pointed in the direction of
> >using a switch - perhaps cable operated.
> >
> >Can you suggest any actual device / source? Am trying
> >to get my orders lined up for collection stateside
> >July / Osh.
>
>
> No particular switch comes to mind. I had several
> builders go the manual battery switch over the years.
> I believe all of them found a suitable device at
> either (1) a marine electrical supply or (2)
> performance automotive supply. Many boats with
> multiple battery installations use manually operated
> heavy duty switches to select which battery is
> in service. Raceways for cars often require a battery
> disconnect switch be readily available to fire/rescue
> crews.
>
> I'm fairly certain you could find one locally. Here
> an example on the 'net . . .
>
> http://www.boatus-store.com/browse/item.asp?IID=17020
>
> Bob . . .
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| From: | Finn Lassen <finnlassen(at)netzero.net> |
| Subject: | Re: battery switch |
Expensive. See
http://jcwhitneyco.com/product.jhtml?CATID=14728
(searched for switch, then master cutoff switches).
Don't know how to remote control, though.
Finn
"Robert L. Nuckolls, III" wrote:
>
> >
> >
> >Bob, folks - some time ago I asked about light-weight
> >battery contactors and was pointed in the direction of
> >using a switch - perhaps cable operated.
> >
> >Can you suggest any actual device / source? Am trying
> >to get my orders lined up for collection stateside
> >July / Osh.
>
> No particular switch comes to mind. I had several
> builders go the manual battery switch over the years.
> I believe all of them found a suitable device at
> either (1) a marine electrical supply or (2)
> performance automotive supply. Many boats with
> multiple battery installations use manually operated
> heavy duty switches to select which battery is
> in service. Raceways for cars often require a battery
> disconnect switch be readily available to fire/rescue
> crews.
>
> I'm fairly certain you could find one locally. Here
> an example on the 'net . . .
>
> http://www.boatus-store.com/browse/item.asp?IID=17020
>
> Bob . . .
________________________________________________________________________________
| From: | "Ned Thomas" <nthomas(at)mmcable.com> |
| Subject: | Re: battery switch |
Try:
http://store.summitracing.com/
and enter "Battery disconnect" in the search box
or to see a bigger picture from the manufacturer
http://www.flaming-river.com/
http://store.summitracing.com/default.asp?target=%2Fsection%2Easp%3Fd%3D11%2
6s%3D14
----- Original Message -----
From: "Ned Thomas" <nthomas(at)mmcable.com>
Subject: Re: AeroElectric-List: Re: battery switch
>
> Here is a couple of battery disconnect switches that can be had with a
lever
> to actuate from the cockpit.
>
>
http://store.summitracing.com/default.asp?target=%2Fsection%2Easp%3Fd%3D11%2
> 6s%3D14
>
>
http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=7165&prmenbr=7
> 6
>
> ----- Original Message -----
> From: "Robert L. Nuckolls, III" <nuckolls(at)kscable.com>
> To:
> Subject: AeroElectric-List: Re: battery switch
>
>
>
> >
> > >
> > >
> > >Bob, folks - some time ago I asked about light-weight
> > >battery contactors and was pointed in the direction of
> > >using a switch - perhaps cable operated.
> > >
> > >Can you suggest any actual device / source? Am trying
> > >to get my orders lined up for collection stateside
> > >July / Osh.
> >
> >
> > No particular switch comes to mind. I had several
> > builders go the manual battery switch over the years.
> > I believe all of them found a suitable device at
> > either (1) a marine electrical supply or (2)
> > performance automotive supply. Many boats with
> > multiple battery installations use manually operated
> > heavy duty switches to select which battery is
> > in service. Raceways for cars often require a battery
> > disconnect switch be readily available to fire/rescue
> > crews.
> >
> > I'm fairly certain you could find one locally. Here
> > an example on the 'net . . .
> >
> > http://www.boatus-store.com/browse/item.asp?IID=17020
> >
> > Bob . . .
> >
> >
> >
> >
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| From: | "Ned Thomas" <nthomas(at)mmcable.com> |
| Subject: | Re: battery switch |
Try:
http://store.summitracing.com/
and enter "Battery disconnect" in the search box
or to see a bigger picture from the manufacturer
http://www.flaming-river.com/
________________________________________________________________________________
| From: | "C D Patterson" <cdp(at)islandnet.com> |
| Subject: | Re: Unable to open Wirebook |
| >
| > http://209.134.106.21/articles/seminar.exe
| >
| > http://209.134.106.21/articles/wirebook.exe
| >
|
| Bob,
|
| Thanks, but...tried everyting you said, disabled the antivirus app, but I'm
| still getting the same "error in zip use PKZipFix" message. The directories
| remain hopelessly empty except for that unexecutable dot exe file ! Wonder
| where this PKZipFix can be get from.
| Is there a URL where I can get those programs in a non-zipped form ?
|
| Thank you,
|
| Gilles
wirebook.exe came down and worked fine.
1.16 megs
seminar.exe displayed the error message above.
it is only 122k in size
Any reason why WinZip could not be used for these? or are they not being zipped
on a Windows Machine?
/Charles
________________________________________________________________________________
| From: | Livingston John W Civ ASC/ENFD <John.Livingston(at)wpafb.af.mil> |
| Subject: | Pros and Cons of Battery Buss Remote from Battery |
Bob, All,
I using 2 batteries (in the tail for CG purposes) and would like to place my
battery busses in the cockpit area. Total load on battery buss would be Essential
bus + EI. Let's call it 15 amps. My current plan is to use fusible links (#18)
at the batteries and run #14 wires to each of the battery busses in the Cockpit
area. Any obvious problems with this approach?
John
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: battery switch |
>
>Expensive. See
>http://jcwhitneyco.com/product.jhtml?CATID=14728
>
>(searched for switch, then master cutoff switches).
>
>Don't know how to remote control, though.
The one I saw used effectively through a forwarded
picture was similar to if not identical to
http://jcwhitneyco.com/item.jhtml;$sessionid$DO2BJHYAAAGRAQSNDV0SFE0CJUOXKIV0?ITEMID=4432&BQ=null
The handle was removed and a belcrank arm fabricated
to replace it. A bowden control was fitted to a hole
in the end of the belcrank to allow push-pull actuation
of the switch from the cockpit. The builder put his
control on a bracket under the seat between his knees
so that the control could extend aft to a rear mounted
battery location.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Unable to open Wirebook |
>
>| >
>| > http://209.134.106.21/articles/seminar.exe
>| >
>| > http://209.134.106.21/articles/wirebook.exe
>| >
>|
>| Bob,
>|
>| Thanks, but...tried everyting you said, disabled the antivirus app, but I'm
>| still getting the same "error in zip use PKZipFix" message. The directories
>| remain hopelessly empty except for that unexecutable dot exe file ! Wonder
>| where this PKZipFix can be get from.
>| Is there a URL where I can get those programs in a non-zipped form ?
>|
>| Thank you,
>|
>| Gilles
>
>wirebook.exe came down and worked fine.
>1.16 megs
>
>seminar.exe displayed the error message above.
>it is only 122k in size
>
>Any reason why WinZip could not be used for these? or are they not being
>zipped
>on a Windows Machine?
Seminar.exe is much larger . . . you didn't get it all. I don't
recall the version of PKzip used to create these files originally.
As self extracting, it shouldn't matter. However, I've combined
all the drawings into a single file:
http://209.134.106.21/articles/wirebook.exe
and compiled it with the latest PKzip utility.
________________________________________________________________________________
| From: | "Andy Karmy" <andy(at)karmy.com> |
| Subject: | Re: C/B question + |
>>Thanks for the reply regarding the use of Digikey W28 series Circuit
>>My choice of using C/Bs is for the following reasons:
>>3. The small C/Bs I mentioned earlier fit my panel and I like the way
One more thing that seems to be missing in the discussion. In looking at these
W28 parts at Digikey, they take 2 fastons right? If so, how are you going to buss
them together to feed them power?
Seems that is one of the discussion points in "the book" about how to eliminate
single points of failure in the power feed to the breakers / fuses. Seems you
would almost need something like the ground block for 12V distribution with single
wires to each CB.
--
Andy Karmy
andy(at)karmy.com
--
________________________________________________________________________________
| Subject: | Re: Unable to open Wirebook |
> Bob,
> I could try e-mailing them directly to you . . . there's a bunch.
If you have no problem sending them, they'll be welcome.
>
> Do you have PKzip on your computer? What version? If it's a windows
> version, it will have a PKzipFix utility built in. See:
>
> http://www.pkware.com/support/faq/?topic=zipg#q3
I searched on my computer, and found winzip while searching pkzip.
but it couldn't open those files, and I got a message saying the files might
be corrupt. Besides, those file seem astonishingly small : circa 100 kbytes.
>
> If you want, I'll try to e-mail the batch . . .
thanks in advance,
Gilles
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Unable to open Wirebook |
>
>
>I searched on my computer, and found winzip while searching pkzip.
>but it couldn't open those files, and I got a message saying the files might
>be corrupt. Besides, those file seem astonishingly small : circa 100 kbytes.
Hmmm . . that explains it. You didn't get the whole file
during download.
> >
> > If you want, I'll try to e-mail the batch . . .
>
>thanks in advance,
I've emailed the two principal drawings as attachments.
Let me know how they come across. If this seems to be working,
we'll mail the pile of smaller but more numerous support
drawings.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: C/B question + |
>
> >>Thanks for the reply regarding the use of Digikey W28 series Circuit
>
> >>My choice of using C/Bs is for the following reasons:
>
> >>3. The small C/Bs I mentioned earlier fit my panel and I like the way
>
>One more thing that seems to be missing in the discussion. In looking at
>these W28 parts at Digikey, they take 2 fastons right? If so, how are you
>going to buss them together to feed them power?
>
>Seems that is one of the discussion points in "the book" about how to
>eliminate single points of failure in the power feed to the breakers /
>fuses. Seems you would almost need something like the ground block for 12V
>distribution with single wires to each CB.
>
>
>--
> Andy Karmy
> andy(at)karmy.com
Good point. I'd not noticed the termination technology offered
on the cited breaker. You're correct in your assertion that "bussing"
for the purposes of eliminating single point failures is going to
add considerably to effort and parts count.
If one really wants circuit breakers, the types most easily
incorporated into a DC power bus distribution architecture are
those with screw connections oriented so as to allow strapping
rows of breakers together with a contiguous strip of copper
or brass . . . i.e. a BUS.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Pros and Cons of Battery Buss Remote from Battery |
>
>
>Bob, All,
>
> I using 2 batteries (in the tail for CG purposes) and would like to
> place my battery busses in the cockpit area. Total load on battery buss
> would be Essential bus + EI. Let's call it 15 amps. My current plan is to
> use fusible links (#18) at the batteries and run #14 wires to each of the
> battery busses in the Cockpit area. Any obvious problems with this approach?
Obviously, what you've proposed will function. Keep in
mind that the goal of circuit protection is to limit the
time that damaging currents will flow in case of faulted
wire and to minimize the pathways in which significant
uncontrolled current can flow in a crash.
If battery busses are not located at the battery then
you have an extended feeder that is capable of large,
sustained fault currents in a crash. I couldn't sell
what you've proposed to the feds . . . and in this case,
I agree with them.
Bob . . .
________________________________________________________________________________
| From: | Livingston John W Civ ASC/ENFD <John.Livingston(at)wpafb.af.mil> |
| Subject: | Re: Pros and Cons of Battery Buss Remote f |
rom Battery
Bob,
I which I could minimize the the pathways, but I'm stuck with the battery in the
back for cg reasons. Large sustained fault currents? It's a fused #14 feeder
wire. I understand that in the event of a crash it may short and spark until
it's fusible link fails, but don't I have the exact same situation if I run the
Essential buss power line (#16 or 14) forward from the battery? I would have
a fusible link at the battery end on this line as well to guard against the
same circumstance.
John
-----Original Message-----
From: Robert L. Nuckolls, III [mailto:nuckolls(at)kscable.com]
Subject: AeroElectric-List: Re: Pros and Cons of Battery Buss Remote
from Battery
>
>
>Bob, All,
>
> I using 2 batteries (in the tail for CG purposes) and would like to
> place my battery busses in the cockpit area. Total load on battery buss
> would be Essential bus + EI. Let's call it 15 amps. My current plan is to
> use fusible links (#18) at the batteries and run #14 wires to each of the
> battery busses in the Cockpit area. Any obvious problems with this approach?
Obviously, what you've proposed will function. Keep in
mind that the goal of circuit protection is to limit the
time that damaging currents will flow in case of faulted
wire and to minimize the pathways in which significant
uncontrolled current can flow in a crash.
If battery busses are not located at the battery then
you have an extended feeder that is capable of large,
sustained fault currents in a crash. I couldn't sell
what you've proposed to the feds . . . and in this case,
I agree with them.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Unable to open Wirebook |
.
> >but it couldn't open those files, and I got a message saying the files
might
> >be corrupt. Besides, those file seem astonishingly small : circa 100
kbytes.
>
> Hmmm . . that explains it. You didn't get the whole file
> during download.
>
> > >
> > > If you want, I'll try to e-mail the batch . . .
> >
> >thanks in advance,
>
> I've emailed the two principal drawings as attachments.
> Let me know how they come across. If this seems to be working,
> we'll mail the pile of smaller but more numerous support
> drawings.
>
> Bob . . .
Great ! They came through OK.
Thank you. Maybe I'll retrieve those messages about an easier than Autocad
CAD app ;-)
Thanks again,
Gilles
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | RE: Pros and Cons of Battery Buss Remote from Battery |
>
>
>Bob,
>
> I which I could minimize the the pathways,
Why? Every airplane built (especially the big guys
with busses all over the place) have one wire that carries
power from a bus via fuse or breaker to some accessory
in the airplane asking for that power. One gizmo, one
wire. How many wires are we talking about? Even with
a dual battery system for dual ignition, we might have
5-8 wires coming off the battery busses as opposed to
two if you extended the buses to some place remote from
the battery . . .
>but I'm stuck with the battery in the back for cg reasons. Large sustained
>fault currents? It's a fused #14 feeder wire. I understand that in the
>event of a crash it may short and spark until it's fusible link fails, but
>don't I have the exact same situation if I run the Essential buss power
>line (#16 or 14) forward from the battery?
Not if you have battery busses and use one of hte
battery fuses to bring the e-bus alternate feed forward.
> I would have a fusible link at the battery end on this line as
> well to guard against the same circumstance.
Fusible links have very long time constants.
How about putting an inline fuse holder
at the source end of the extensions wire and use
a real fuse. But if it were my airplane, I'd leave
the busses at the batteries and bring whatever wires
needed to tap those busses to those locations.
I much rather have a bunch of little wires with
fuses getting faulted than one fat wire with
a fuselink.
Bob . . .
________________________________________________________________________________
| From: | N1deltawhiskey(at)aol.com |
| Subject: | Re: Wiring from scratch : where do you start ? |
In a message dated 4/7/2002 3:36:02 PM Pacific Daylight Time,
Gilles.Thesee@ac-grenoble.fr writes:
> Anyone know of a practical coding method for numbering the wires in a
> logical way ?
>
What I have done is to identify each device with an alphanumeric 2-4 letter
symbol, and connectors with 3 digit numbers (first being the connector, the
second two being the pin number). My labels will consist of a pair of codes,
the one nearest the connector/devise being that pin designation, and the one
away from the connection/devise indicating where the wire goes. The other
end of the wire will have a similar tag. The label will be within 6" of the
terminal, hence, wires less than 12" need have only one tag midway.
Examples: Busses are labeled B+ or B- followed by a cap letter such as M for
main, E for essential, G for gauges, I for instruments, L for lighting, etc.
Switches and switchbreakersare S01, ..., S34. Fuses are F0n (n=numeric) for
panel mounted fuses. The fuse blocks are F10-F14 and F20-F24 for the
essential bus, and F30-F39 and F40-F49 for the main bus.
Connectors are 100, 200, etc with the last two digits of that connector being
the connector pin number. In the case of the wings, there is a connector at
the root and at the tip. The left wing root connector is 701-716, the
wingtip connector 740-752.
Avionics (minimal UPS Apollo for now, more later) uses A1 for the SL10 or 15
audio panel, A2 for the MX20, A3c and A3n for the SL30 com and nav sides
respectively, A6c and A6g for the com and gps respectively, and A7 for the
transponder.
Hope this helps.
Regards, Doug Windhorn
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | So many commands, so little time . . . |
>
>
>Now all I have to do is try to master that Autocad app. This will prove
>another story !
>
>cheers,
>
>Gilles
Here's a suggestion. In the main AutoCAD directory you will find
a file called (something).pgp . . . it's the "pgp" part that's
important. Copy the stock file away somewhere for future reference
and use Notepad to cut/paste the following into a file of
the same name.
AR, *ARRAY
B, *BLOCK
BR, *BREAK
C, *CHANGE
CH, *CHAMFER
CI, *CIRCLE
CO, *COPY
DI, *DIST
DT, *DTEXT
DV, *DVIEW
E, *ERASE
ED, *DDEDIT
EX, *EXTEND
F, *FILLET
I, *INSERT
L, *LINE
LA, *LAYER
LI, *LIST
LT, *LINETYPE
M, *MOVE
MI, *MIRROR
OS, *OSNAP
P, *PAN
PE, *PEDIT
PL, *PLINE
PG, *POLYGON
R, *REDRAW
RE, *REGEN
RO, *ROTATE
S, *STRETCH
SC, *SCALE
SCR, *SCRIPT
ST, *STYLE
T, *TRIM
V, *VIEW
WB, *WBLOCK
XP, *EXPLODE
Z, *ZOOM
The .pgp file is a user customizable overlay or substitution
file that allows you to create one or two-letter commands that
AutoCAD will understand as the fully spelled out command. If you open the
stock .pgp file, you'll find hundreds of commands . . . the vast
majority of which you'll never need/use. The list above is my
personal .pgp file that represents all the commands I need for
about 99% of the work I do. I learned to drive AutoCAD by steering
the mouse in my left hand and entering one or two-letter
commands with the right.
I found this to be much faster than using the pull-down menus . . .
this list above also quantifies the task for helping others get
started with this really powerful software. I'll suggest that
this abbreviated .pgp file represents two opportunities: A way
to get AutoCAD to do most important things with a minimum of
keystrokes and (2) it becomes a list of things to get familiar
with in terms of getting AutoCAD to work for you. Most tutorials
set out with the notion of teaching you about EVERYTHING AutoCAD
can do . . . Without some notion of what you need, you're
suckered into spending a lot of time learning what the author
of the book thinks you ought to know.
Become selectively familiar first with the list of commands
I've cited and add other commands as you need them later. I guarantee
that things will move ahead much faster for you.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: crimping fastons |
Hi,
Does the bare copper conductor inside the crimp joint oxidize over time?
When crimping copper stranded wire to a faston or other type of connector,
can one tin the wire first to aid in oxidation prevention?
Thanks,
Steve
Not necessary. One of the goals of crimped terminal
technology is to achieve gas-tight joints. See:
http://209.134.106.21/articles/rules/review.html
Once the terminal is installed by either solder
or crimping, the metal to metal contact is impervious
to external stresses.
Bob . . .
--------------------------------------------
| People are far more willing to pay |
| for being amused than for anything else. |
| -Thomas Edison- |
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: where do you start ? |
>
>In a message dated 4/7/2002 3:36:02 PM Pacific Daylight Time,
>Gilles.Thesee@ac-grenoble.fr writes:
>
> > Anyone know of a practical coding method for numbering the wires in a
> > logical way ?
> >
What Doug has described below is a means by which reference designators
are applied to hardware . . .this is a good thing to do because it
lets you put a simple label on a component symbol in the wiring diagram
to key it to the bill of materials built up in some nice data base
program like Excel or Access . . ..
If I understand your question correctly, you're asking about identifying
wires. You can be as simple or as complicated as you like. I show
a technique for putting labels on wires at:
http://www.aeroelectric.com/Catalog/wiring/wiring.html#s817c
and
http://www.aeroelectric.com/Catalog/wiring/s817c.jpg
Use the smallest font your computer will generate (typically 6pt)
on full sheets of Avery label material. The illustration shows some pretty
verbose labels. I'll suggest that a simple numbering of each
wire segment with a unique number is sufficient. It's not even
necessary that you use the numbers in order or that all numbers
in any given sequence be used to label a wire. What you're really
trying to do is tie individual wires down to a conductor depicted in your
wirebook. You can spend a lot of time putting a name on a wire
when a simple number ultimately does as good a job.
>What I have done is to identify each device with an alphanumeric 2-4 letter
>symbol, and connectors with 3 digit numbers (first being the connector, the
>second two being the pin number).
>Avionics (minimal UPS Apollo for now, more later) uses A1 for the SL10 or 15
>audio panel, A2 for the MX20, A3c and A3n for the SL30 com and nav sides
>respectively, A6c and A6g for the com and gps respectively, and A7 for the
>transponder.
Bob . . .
________________________________________________________________________________
| From: | "John W Livingston" <jliving(at)erinet.com> |
| Subject: | Re: RE: Pros and Cons of Battery Buss Remote from Battery |
Bob,
Thanks for the input. I have to mull this over a little. I never thought
that a fusible link would be too slow in responding to a short. You used one
to connect your E buss. Your about right on the wire count coming off of
the batteries. E buss, left and right ignition wires off of each battery
plus maybe 2 or 3 more for a total of about 8 to 9. The biggest being the E
buss wires (#16). I still don't see the big difference between a fused #14
battery feed wire carrying 11 amps versus a #16 carrying 7 amps? I do see
that if a battery feed shorted everything on that buss would fail, but that
is why I have 2 feeds. Yes, I guess it would be a little better to use
separate wires, but its damn inconvenient. All that extra wiring and what an
awful place for fuse blocks. Decisions, decisions.......
John
----- Original Message -----
From: Robert L. Nuckolls, III <nuckolls(at)kscable.com>
Subject: AeroElectric-List: RE: Pros and Cons of Battery Buss Remote from
Battery
>
> >
> >
> >Bob,
> >
> > I which I could minimize the the pathways,
>
> Why? Every airplane built (especially the big guys
> with busses all over the place) have one wire that carries
> power from a bus via fuse or breaker to some accessory
> in the airplane asking for that power. One gizmo, one
> wire. How many wires are we talking about? Even with
> a dual battery system for dual ignition, we might have
> 5-8 wires coming off the battery busses as opposed to
> two if you extended the buses to some place remote from
> the battery . . .
>
>
> >but I'm stuck with the battery in the back for cg reasons. Large
sustained
> >fault currents? It's a fused #14 feeder wire. I understand that in the
> >event of a crash it may short and spark until it's fusible link fails,
but
> >don't I have the exact same situation if I run the Essential buss power
> >line (#16 or 14) forward from the battery?
>
>
> Not if you have battery busses and use one of hte
> battery fuses to bring the e-bus alternate feed forward.
>
>
> > I would have a fusible link at the battery end on this line as
> > well to guard against the same circumstance.
>
>
> Fusible links have very long time constants.
> How about putting an inline fuse holder
> at the source end of the extensions wire and use
> a real fuse. But if it were my airplane, I'd leave
> the busses at the batteries and bring whatever wires
> needed to tap those busses to those locations.
> I much rather have a bunch of little wires with
> fuses getting faulted than one fat wire with
> a fuselink.
>
> Bob . . .
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| Subject: | Re: Wiring from scratch : where do you start ? |
Doug,
Thanks for the input.
> What I have done is to identify each device with an alphanumeric 2-4
letter
> symbol, and connectors with 3 digit numbers (first being the connector,
the
> second two being the pin number). My labels will consist of a pair of
codes,
> the one nearest the connector/devise being that pin designation, and the
one
> away from the connection/devise indicating where the wire goes. The other
> end of the wire will have a similar tag. The label will be within 6" of
the
> terminal, hence, wires less than 12" need have only one tag midway.
>
......snip.......
> Hope this helps.
Everything helps. Now I can see more clearly what our wiring will look like,
but we still have a long way to go before everithing is decided.
cheers,
Gilles
________________________________________________________________________________
| Subject: | Re: where do you start ? |
>
Bob,
. . .this is a good thing to do because it
> lets you put a simple label on a component symbol in the wiring diagram
> to key it to the bill of materials built up in some nice data base
> program like Excel or Access . . ..
Well, er, that'll be Excel, then ;-)
>
> If I understand your question correctly, you're asking about
identifying
> wires. You can be as simple or as complicated as you like. I show
> a technique for putting labels on wires at:
I was thinking of using your stuff..
. What you're really
> trying to do is tie individual wires down to a conductor depicted in
your
> wirebook. You can spend a lot of time putting a name on a wire
> when a simple number ultimately does as good a job.
>
To date, we are trying to lay things down on paper, while making one
decision at a time : which piece of equipment, which location, what kind of
protection...We're in the process of choosing the radio and XPDR, and
sorting out the flap command system.
Cheers,
Gilles
My goal is to provide a fairly complete wirebook before starting on the
airplane.
________________________________________________________________________________
| Subject: | 12volt vs. 24 volt system |
| From: | tjpackard(at)mmm.com |
22, 2000) at 04/10/2002 10:58:16 AM
Bob:
I have a Lycoming IO-540 that I plan on putting in a Super Rebel. Right
now it has a 24volt system and I'm planning on changing to 12 volt. Are
there any reasons why this is not a good idea?
Thanks,
Tom Packard
Somerset, WI
________________________________________________________________________________
| From: | "Sanders, Andrew P" <andrew.p.sanders(at)boeing.com> |
| Subject: | Wire Braid Sizing |
I have a piece of certificated, Kansas aluminum that is undergoing some
firewall forward work. The wiring to the alternator is 8 gauge shielded.
In several places the shield is in really rough shape. My mechanic & I
understand that this shielding doesn't do much (if anything) to reduce
noise, but being certificated, the path of least resistance (yes, pun
intended) is to keep it in the factory configuration.
The wire itself is in good shape and rather then replace the whole wire,
we'd like to just replace the shield. There are several sources of braided
shield in various dimensions, but they are always listed by width "rolled
flat". Is there a table of what the I.D. of the braid would be when it
isn't flat? How else would we figure what size to order to cover a
particular wire or bundle?
Thanks for the help.
Andrew Sanders
________________________________________________________________________________
| From: | Michel Therrien <mtherr(at)yahoo.com> |
| Subject: | 2-1/4" transponders |
Is the MicroAir now available? Or is it still due for
next week? :-)
I called Becker last week and apparently, their new
transponder is approved and now shipping. He said
that the first production run was delivered to those
who placed orders (since Oshkosh last summer).
Another batch should be available to the dealers
within a few weeks (oups!).
Their website has been updated with information on
that unit and Aircraft Spruce (and others) have
pricing information for the transponder.
OK... anybody here ordered it and received it?
=====
----------------------------
Michel Therrien CH601-HD
http://pages.infinit.net/mthobby
http://mthobby.pcperfect.com/ch601
http://taxes.yahoo.com/
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Wire Braid Sizing |
>
>
>I have a piece of certificated, Kansas aluminum that is undergoing some
>firewall forward work. The wiring to the alternator is 8 gauge shielded.
>In several places the shield is in really rough shape. My mechanic & I
>understand that this shielding doesn't do much (if anything) to reduce
>noise, but being certificated, the path of least resistance (yes, pun
>intended) is to keep it in the factory configuration.
>
>The wire itself is in good shape and rather then replace the whole wire,
>we'd like to just replace the shield. There are several sources of braided
>shield in various dimensions, but they are always listed by width "rolled
>flat". Is there a table of what the I.D. of the braid would be when it
>isn't flat? How else would we figure what size to order to cover a
>particular wire or bundle?
That's pretty easy . . . 2x the "flat" dimension is
approximately the circumference of the round dimension.
Further, this number is a minimum value . . . most
braid lay-ups will allow a degree of bunching that will
expand the i.d. to 2 or 3 times the optimize tight
value. Unshielded 22759/16-8 is about .25" diameter
for a circumference of about .78" . . . sooo, a flat
braid of .375 would do just fine.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: 12volt vs. 24 volt system |
>
>Bob:
>I have a Lycoming IO-540 that I plan on putting in a Super Rebel. Right
>now it has a 24volt system and I'm planning on changing to 12 volt. Are
>there any reasons why this is not a good idea?
>
>Thanks,
>Tom Packard
>Somerset, WI
None that I can think of . . . a 24 volt system shuts you
completely out for taking advantage of automotive
products that are most suitable for use on airplanes
at a fraction of the cost.
Weight savings touted for 24-volt systems don't materialize
until you're building a really big airplane . . . like a
B-17. If you rip all the electrical hardware out of otherwise
be surprised to see more than a few pounds difference.
I'll shuck 5# off my bod before I'll pay the cost and
inconvenience of going 24v in a project.
Bob . . .
________________________________________________________________________________
| From: | Steven Kay <skay(at)optonline.net> |
| Subject: | Re: 12volt vs. 24 volt system |
I have seen that there's a lot of used Garmin stuff out there that's 24 volt only.
While I
don't think it could out weigh the 12 volt auto parts, it's perhaps something to
consider.
-Steve
"Robert L. Nuckolls, III" wrote:
>
> >
> >Bob:
> >I have a Lycoming IO-540 that I plan on putting in a Super Rebel. Right
> >now it has a 24volt system and I'm planning on changing to 12 volt. Are
> >there any reasons why this is not a good idea?
> >
> >Thanks,
> >Tom Packard
> >Somerset, WI
>
> None that I can think of . . . a 24 volt system shuts you
> completely out for taking advantage of automotive
> products that are most suitable for use on airplanes
> at a fraction of the cost.
>
> Weight savings touted for 24-volt systems don't materialize
> until you're building a really big airplane . . . like a
> B-17. If you rip all the electrical hardware out of otherwise
> be surprised to see more than a few pounds difference.
>
> I'll shuck 5# off my bod before I'll pay the cost and
> inconvenience of going 24v in a project.
>
> Bob . . .
>
________________________________________________________________________________
| From: | Hebeard2(at)aol.com |
| Subject: | Re: Wiring from scratch : where do you start ? |
There are probably almost as many methods of wire identification as there are
pieces of wire. On page 8 of the first issue for 2001 of Van's publication
the RVator, RV-6A builder Bob Hahn presents a very logical method of wire
labeling. Each label starts with a description of the source of power,
followed by the three symbols <->, followed by a description of the
destination of the wire. He gives as an example "Fuel Pump +12V <-> Fuel Pump
Switch". To me stating the voltage is of little use except to designate that
the wire is coming from the source of power. Perhaps of more value would be
the identification of the bus or fuse block from which the wire originated.
In this case if the fuel pump were to be powered from the Main Power Buss
(MPB), the label would then read "Fuel Pump, MPB <-> Fuel Pump Switch". A
system of identifying abbreviations for the various busses, CBs and fuse
blocks, similar to those suggested by Doug Windhorn, would simplify and
shorten the length of the labels.
Bob continues with a well thought out plan of using Microsoft Excel to print
out the labels in font size seven, inserting them in a clear shrink tube, and
slipping them over each end of a wire before shrinking. If a label cannot be
slipped over a wire, the label can also be slipped over the tail of a cable
tie after it has been cinched up tight on the wire. The use of colored paper
to make the labels opens even more avenues of easy ready identification.
Harley E. Beard, RV-6A Finish Kit
________________________________________________________________________________
| Subject: | Re: Wiring from scratch : where do you start ? |
Hebeard2(at)aol.com wrote:
> followed by the three symbols <->, followed by a description of the
> destination of the wire. He gives as an example "Fuel Pump +12V <-> Fuel Pump
*** Any wire can be labelled by :
* What this end connects to: makes assembly easier.
or
* What the OTHER end connects to: makes troubleshooting easier.
Which to use?
- Jerry Kaidor ( jerry(at)tr2.com )
________________________________________________________________________________
| From: | "Tom Barnes" <skytop(at)megsinet.net> |
Bob,
My marker beacon receiver (RST product) uses an RCA connector for
signal input. I couldn't find any documentation on procedures for
connecting coax to this, so left to my own imagination, it seems
reasonable to solder the center conductor to the center pin and to
gather the shield and solder it to the outter part of the connector and
possibly put some heat shrink over the soldered shield to hide the mess.
Will you pIease comment if this is correct and on anything that I've not
considered?
Thanks,
Tom Barnes
________________________________________________________________________________
| Subject: | EL Cockpit Lighting |
Hi all,
Some months ago there has been a thread on panel EL lighting.
Can anyone around here answer some questions ?
Is the stuff from Aeroenhancement really the same as that of
http://www.e-lite.com/news.htm ?
For those who ordered, are you satisfied whit the product, and which color
do you think is best for panel lighting ? Do you feel one inch is a correct
width for a glareshield installation ?
Is it possible to order a length, and custom cut it into halves to light
diferent parts of the panel ? Or are the connections factory built ?
Any comments appreciated,
Thanks,
Gilles
----- Message d'origine -----
De : "Livingston John W Civ ASC/ENFD"
:
Envoy : jeudi 27 septembre 2001 15:57
Objet : RE: AeroElectric-List: EL Cockpit Lighting
>
> Mark, All,
>
> You might want to check out http://www.e-lite.com/news.htm They
manufacture the stuff and have some nice sample kits, power supplies for 12
volt systems etc.
>
> John
>
>
> -----Original Message-----
> From: czechsix(at)juno.com [mailto:czechsix(at)juno.com]
> To: aeroelectric-list(at)matronics.com
> Subject: AeroElectric-List: EL Cockpit Lighting
>
>
> Bob (or anyone else who wants to jump in),
>
> I am considering using electroluminescent lighting in my RV-8A cockpit.
> Specifically, there's a brand-name called "Flatlite" that can be obtained
> in almost any shape or size, and all the colors of the rainbow. The
> distributor I've been talking to is at
> http://beingseentechnologies.goemerchant2.com. My intent is to get a 2"
> x 24" strip (blue, green, or white.....haven't decided which color yet)
> and stick it to the underside of my glareshield. It won't be directly
> visible when seated in the cockpit, but it will cast a soft glow down on
> the panel. This seems to be an ideal way to light the panel with a
> minimum of glare on the panel or canopy. The product is dimmable by
> varying the input voltage from 12 VDC down to 7 VDC (after which it shuts
> off).
>
>
> Any other input on this subject.....anyone who's tried it....any problems
> or gotchas.....speak up before I send my $65.
>
> Thanks,
>
> --Mark Navratil
________________________________________________________________________________
| From: | Charlie and Tupper England <cengland(at)netdoor.com> |
| Subject: | Re: RCA connectors |
Tom Barnes wrote:
>
>
> Bob,
> My marker beacon receiver (RST product) uses an RCA connector for
> signal input. I couldn't find any documentation on procedures for
> connecting coax to this, so left to my own imagination, it seems
> reasonable to solder the center conductor to the center pin and to
> gather the shield and solder it to the outter part of the connector and
> possibly put some heat shrink over the soldered shield to hide the mess.
> Will you pIease comment if this is correct and on anything that I've not
> considered?
>
> Thanks,
> Tom Barnes
>
Tom,
You've got it right on the actual wiring, but instead of
using shrink to 'hide the mess' you can get an rca connector
with a metal case. Just slide it on the wire before
soldering the connections, then crimp (not a technical term
here) the strain-relief blades over the insulation, then
screw the metal cover over everything. Radio Shack probably
has them, but this is one case where you'd really be better
off finding an electronics supply house that stocks
Switchcraft brand connectors. You will get pre-tinned solder
points which will make your life a lot easier if you have
limited experience with soldering.
Charlie
________________________________________________________________________________
| Subject: | Re: RCA connectors |
Charlie and Tupper England wrote:
>
>
> Tom Barnes wrote:
> >
> >
> > Bob,
> > My marker beacon receiver (RST product) uses an RCA connector for
> > signal input. I couldn't find any documentation on procedures for
> > connecting coax to this, so left to my own imagination, it seems
> > reasonable to solder the center conductor to the center pin and to
> > gather the shield and solder it to the outter part of the connector and
*** Instead of "gathering the shield", I would just fair it over the entire
circumference of the connector and solder it all the way around. That will
get you good sheilding. Then I would put a piece of shrink tubing over the
whole thing ( except for the center pin, of course ). The best would be
an RCA plug with a teflon insulator, if such is available.
- Jerry Kaidor ( jerry(at)tr2.com )
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: 2-1/4" transponders |
They ARE making US deliveries. The radios are coming on-shore
at the rate of 36 every two weeks according to my last
contact with EDMO. I'm supposed to get part of my backorders
out of the next shipment. He thought he might ship me 3
radios out of the 10 on order. As soon as they get here and
I can develop the interconnect harness, I'll send out
letters to the earliest three folks on my interest list
and start working it from there.
EDMO told me that there are about 200 radios on back order
so it will take some time to fill the pipe . . . but they
are indeed here.
Bob . . .
________________________________________________________________________________
| From: | "Sanders, Andrew P" <andrew.p.sanders(at)boeing.com> |
| Subject: | Re: Re: Wire Braid Size |
>>Is there a table of what the I.D. of the braid would be when it
>>isn't flat? How else would we figure what size to order to cover a
>>particular wire or bundle?
>That's pretty easy . . . 2x the "flat" dimension is
>approximately the circumference of the round dimension.
>Further, this number is a minimum value . . . most
>braid lay-ups will allow a degree of bunching that will
>expand the i.d. to 2 or 3 times the optimize tight
>value. Unshielded 22759/16-8 is about .25" diameter
f>or a circumference of about .78" . . . sooo, a flat
>braid of .375 would do just fine.
>Bob . . .
That's entirely too easy! Didn't know if we needed to allow for the
thickness of the braid or if it was "bunchable".
Thanks,
Andrew
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: where do you start ? |
>
>Hebeard2(at)aol.com wrote:
> > followed by the three symbols <->, followed by a description of the
> > destination of the wire. He gives as an example "Fuel Pump +12V <->
> Fuel Pump
>
>*** Any wire can be labelled by :
>
> * What this end connects to: makes assembly easier.
>
> or
>
> * What the OTHER end connects to: makes troubleshooting easier.
>
> Which to use?
Who trouble shoots without the wirebook? The number
"32" on each end ties it nicely to the wirebook segment
marked "32" no matter which end goes where.
Big airplanes have fancy numbering systems that make
it easier to deal with bundles having a LOT of wires
in them . . . but no system I've ever seen puts anything
on the wire that encourages you to deduce anything about
that wire without referring to the wirebook.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: RCA connectors |
>
>Bob,
> My marker beacon receiver (RST product) uses an RCA connector for
>signal input. I couldn't find any documentation on procedures for
>connecting coax to this, so left to my own imagination, it seems
>reasonable to solder the center conductor to the center pin and to
>gather the shield and solder it to the outter part of the connector and
>possibly put some heat shrink over the soldered shield to hide the mess.
>Will you pIease comment if this is correct and on anything that I've not
>considered?
>
>Thanks,
> Tom Barnes
The first thing I would do is see how hard it would be to
change out connector on the receiver for a TNC, BNC or
SMA style connector. If that's not possible or practical
for whatever reason then see:
http://209.134.106.21/articles/rca_plug/rca1.jpg
http://209.134.106.21/articles/rca_plug/rca2.jpg
http://209.134.106.21/articles/rca_plug/rca3.jpg
http://209.134.106.21/articles/rca_plug/rca4.jpg
http://209.134.106.21/articles/rca_plug/rca5.jpg
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Wire vs. Braid Size |
>
>
> >>Is there a table of what the I.D. of the braid would be when it
> >>isn't flat? How else would we figure what size to order to cover a
> >>particular wire or bundle?
>
>
> >That's pretty easy . . . 2x the "flat" dimension is
> >approximately the circumference of the round dimension.
> >Further, this number is a minimum value . . . most
> >braid lay-ups will allow a degree of bunching that will
> >expand the i.d. to 2 or 3 times the optimize tight
> >value. Unshielded 22759/16-8 is about .25" diameter
> f>or a circumference of about .78" . . . sooo, a flat
> >braid of .375 would do just fine.
>
> >Bob . . .
>
>That's entirely too easy! Didn't know if we needed to allow for the
>thickness of the braid or if it was "bunchable".
Even if the braid is too big and pulls tight without
coming down snug on the wire, the shielding effect is
still the same . . . assuming of course that shielding
is doing you any good in the first place . . .
Bob . . .
________________________________________________________________________________
| From: | "Mark D. Dickens" <mddickens(at)mindspring.com> |
Bob, I am building an RV-8 and was reading (again) the 'Connection. In
Figure 12-8, you show the schematic for a solid state dimmer, but don't show
the values for the resistors or the capacitors. I am thinking that I might
be able to cobble this together as a beginning project. Do you have any
further details for this or know where I might get some?
Thanks
Mark Dickens
Highlands Ranch, CO
________________________________________________________________________________
| From: | "Jim Cameron" <toucan(at)78055.com> |
| Subject: | Ritchie electronic compass |
Bob,
Thanks for the feedback and comments. The compensation procedure
for the Ritchie electronic compass consists of grounding a wire in the
harness, then turning one to two full circles. The readout unit (in the
panel) pegs at a North heading during this procedure, then switches to a
south indication when it's done, or, in the case of bad internal data
(??), it will switch to an East indication. You then disconnect the
grounded lead. I think it's supposed to compensate for big iron chunks
nearby, like a marine engine.
I did this three times, and each time the headings after the
compensation were displaced another 5 or so degrees from what it should
have been (i.e., checked against runway headings, GPS output, whiskey
compass, etc.). Dunno why.
The unit is supposed to be compensated for + or - 45 degrees of roll
(which you might expect in a boat), but I found it was not, really.
The other thing that led me to abandon it was that I find I use the
DG as my primary heading reference, even though I have GPS, compass,
etc.
It would be fun to experiment with other marine units, but I'm
afraid I just haven' t the time or money to do it. I had a sailboat a
few years ago with a flux-gate compass hooked to an autopilot, and all
worked flawlessly. The cost for a whole instrumentation package
including the autopilot was about $2500. Most of the newer marine
products communicate via the NMEA interface -- don't know how close this
is to anything we use in the air.
JIm Cameorn
Lancair Super ES
________________________________________________________________________________
| From: | Gary Coonan <gcoonan(at)comcast.net> |
| Subject: | Re: wire labeling |
Here is an idea for wire labeling that has worked really well for me. I
have a Kroy K3000-PC shrink wrap printer. I just go into my Word/Excel
and type the label and it print right onto the shrink wrap in waterproof
ink. You can write a paragraph if you want. I do not use any codes, I
just type out exactly what the wire is. Since it is so easy to label, I
do not worry about keeping it short. The shrink wrap feeds out and you
have a trimming knife on the side of the printer to cut it off. You can
buy different size shrink wrap cartridges that just pop into the
printer, so you can change for wire thickness in about 3 seconds. The
cartridges have about 10' of shrink wrap, so that last a while. If I
remember, the printer was about $100 and the shrink wrap was about what
shrink wrap normally costs. I got the printer off the web somewhere,
don't remember. The printer is about the size of a brick, they also have
handheld units that would work well too.
I am a streetrodder and going back to fix something that I did a couple
of years ago and seeing the label without having to decode them is one
of the best tricks that I have used over the years. Anyway, it works
for me.
Gary Coonan
Tennessee, -7 fuselage
-----Original Message-----
________________________________________________________________________________
| From: | "John W Livingston" <jliving(at)erinet.com> |
| Subject: | Re: EL Cockpit Lighting |
Gilles,
I don't know if it's the same product, but it works great. I ordered the
SKT003 demo kit . It comes with a 1x36inch blue green light and a 6x6 white
light. It has an inverter that will drive approximately 30 sq inches of
lighting to maximum brightness. It can drive both of these lights (72 sq
inches) to a very reasonable level of brightness. This kit currently costs
$75. I am hooking it up through one of Bob's dimmers. I get an overhead
light and a panel light set up for a little over $100 counting the cost of
the dimmer.
Very satisfied. The blue green looks good on the panel, but haven't flown
yet. This looks like the color Aeroenhancement uses for it's glareshield
light. I think the overhead works better in white. I don't like reading
color maps in colored light. One inch width is more than adequate. Half or
quarter inch would do the job. The kit comes factory cut and assembled as
pictured on there web sight. They have instructions on the web for cutting,
attaching leads, and sealing the lights. It all looks very straight forward,
though I haven't had to do it because I'm using the kit lights as they came.
They want ot sell in bulk, but they seem to be nice folk to deal with.
I really think this is the way to light a plane. I just hope I don't run
into any interference problems with the 650 hz ac power. I haven't so far,
but haven't fired up the radios yet.
John
----- Original Message -----
From: gilles.thesee <Gilles.Thesee@ac-grenoble.fr>
>
> Hi all,
>
> Some months ago there has been a thread on panel EL lighting.
>
> Can anyone around here answer some questions ?
>
> Is the stuff from Aeroenhancement really the same as that of
> http://www.e-lite.com/news.htm ?
> For those who ordered, are you satisfied whit the product, and which color
> do you think is best for panel lighting ? Do you feel one inch is a
correct
> width for a glareshield installation ?
> Is it possible to order a length, and custom cut it into halves to light
> diferent parts of the panel ? Or are the connections factory built ?
>
> Any comments appreciated,
>
> Thanks,
>
> Gilles
>
>
> ----- Message d'origine -----
> De : "Livingston John W Civ ASC/ENFD"
> :
> Envoy : jeudi 27 septembre 2001 15:57
> Objet : RE: AeroElectric-List: EL Cockpit Lighting
>
>
>
> >
> > Mark, All,
> >
> > You might want to check out http://www.e-lite.com/news.htm They
> manufacture the stuff and have some nice sample kits, power supplies for
12
> volt systems etc.
> >
> > John
> >
> >
> > -----Original Message-----
> > From: czechsix(at)juno.com [mailto:czechsix(at)juno.com]
> > To: aeroelectric-list(at)matronics.com
> > Subject: AeroElectric-List: EL Cockpit Lighting
> >
> >
> >
> > Bob (or anyone else who wants to jump in),
> >
> > I am considering using electroluminescent lighting in my RV-8A cockpit.
> > Specifically, there's a brand-name called "Flatlite" that can be
obtained
> > in almost any shape or size, and all the colors of the rainbow. The
> > distributor I've been talking to is at
> > http://beingseentechnologies.goemerchant2.com. My intent is to get a 2"
> > x 24" strip (blue, green, or white.....haven't decided which color yet)
> > and stick it to the underside of my glareshield. It won't be directly
> > visible when seated in the cockpit, but it will cast a soft glow down on
> > the panel. This seems to be an ideal way to light the panel with a
> > minimum of glare on the panel or canopy. The product is dimmable by
> > varying the input voltage from 12 VDC down to 7 VDC (after which it
shuts
> > off).
> >
> >
> > Any other input on this subject.....anyone who's tried it....any
problems
> > or gotchas.....speak up before I send my $65.
> >
> > Thanks,
> >
> > --Mark Navratil
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| From: | Richard RIley <Richard(at)riley.net> |
| Subject: | Flight Director driver |
For my attitude indicator I'm using an AIM ARU-48A, a backup gyro out of an
F-18/A. It's 110v 400hz 3 phase, and after a LONG search I've found an
inverter to run it.
In addition to a cageable ball, it has a built in turn coordinator and slip
indicator, and a pair of flight director needles. I've gotten the pin out
from AIM.
Is there any reasonable way to drive the flight director indicators, shy of
a very serious autopilot? I understand that the UPSAT GX-60 is shipping
with roll steering indication output - is that all I need for the
horizontal needle?
________________________________________________________________________________
| Subject: | EL Cockpit Lighting |
> I don't know if it's the same product, but it works great. I ordered the
> SKT003 demo kit . It comes with a 1x36inch blue green light and a 6x6
white
> light. It has an inverter that will drive approximately 30 sq inches of
> lighting to maximum brightness. It can drive both of these lights (72 sq
> inches) to a very reasonable level of brightness. This kit currently
costs
> $75. I am hooking it up through one of Bob's dimmers. I get an overhead
> light and a panel light set up for a little over $100 counting the cost of
> the dimmer.
>
> Very satisfied. The blue green looks good on the panel, but haven't
flown
> yet. This looks like the color Aeroenhancement uses for it's glareshield
> light. I think the overhead works better in white. I don't like reading
> color maps in colored light. One inch width is more than adequate. Half
or
> quarter inch would do the job. The kit comes factory cut and assembled as
> pictured on there web sight. They have instructions on the web for
cutting,
> attaching leads, and sealing the lights. It all looks very straight
forward,
> though I haven't had to do it because I'm using the kit lights as they
came.
> They want ot sell in bulk, but they seem to be nice folk to deal with.
John,
Your answer is a good news for us.
Thank you,
Gilles
________________________________________________________________________________
| Subject: | Fig Z16 Rotax diagram questions |
Hi, Bob
Re Rotax 912/914 diagram:
Question 1 :
While studying Fig Z 16 in Rev 10, I'm not sure I really understand the role
or the 5 A breaker in addition to the fuselink between the masterswitch and
main bus.
I gather this breaker trips when the crowbar module pulls pin 4 to ground in
case of overvoltage. It so de-energizes the relay, disconnecting the
alternator feeder from the battery contactor and main bus.
Is that correct ?
But then, why the fuselink at the main bus ?
Question 2 :
On the same diagram, why does the fuselink at the starter contactor seem to
be downstream from the feeder ?
If this is really so, what protects the feeder between the capacitor and the
OV relay ?
Or is it that in case of fault on the feeder, the curent flows from the
battery to the faulted point ?
I'm not sure I'm interpreting the diagram the right way, so please correct
me where I'm wrong.
And please pardon me if I use inadequate technical terms.
Thanks to the knowledge you share with us, the outlines of our future wiring
slowly emerge.
Thank you
Gilles
________________________________________________________________________________
| From: | "Richard V. Reynolds" <rvreynolds(at)macs.net> |
| Subject: | AMP HDP-22 Pin Crimper |
My Apollo UPS ACU connector uses AMP high density pins HDP-22 (.030) AMP
p/n 748333-4.
The $10 crimp tools do not form the crimp into a "nice .040 inch
diameter required for easy insertion and more importantly easy removal.
AMP recommends the following Crimp Tools.
AMP Certi-Crimp p/n 90430-1
AMP Pro-Crimper II p/n 90800-1
These are very expensive tools $250-$450. Does anyone have an equivalent
alternative or be willing to lend or rent the AMP tool.
Richard Reynolds, Norfolk, VA RV-6A
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Ritchie electronic compass |
>
>Bob,
>
> Thanks for the feedback and comments. The compensation procedure
>for the Ritchie electronic compass consists of grounding a wire in the
>harness, then turning one to two full circles. The readout unit (in the
>panel) pegs at a North heading during this procedure, then switches to a
>south indication when it's done, or, in the case of bad internal data
>(??), it will switch to an East indication. You then disconnect the
>grounded lead. I think it's supposed to compensate for big iron chunks
>nearby, like a marine engine.
Aha! A "smart" swinging feature . . . that seems to be not
so smart. Do they tell you to ground the wire with the
vehicle headed on magnetic north? I'm mystified as to how their
internal workings will deduce intermediate headings during
rotation unless they're simply assuming that your turning rate
is a constant . . . it would have to clock the time it takes
to run from magnetic north back to magnetic north, plot the
perceived headings against deduced headings and build an
error lookup table . . . nice if you can do it. I can see this
happening with some accuracy in a boat, I'm skeptical about an
airplane.
> I did this three times, and each time the headings after the
>compensation were displaced another 5 or so degrees from what it should
>have been (i.e., checked against runway headings, GPS output, whiskey
>compass, etc.). Dunno why.
It wouldn't hurt to talk to one of their service technicians.
Even tho you've abandoned the product for your application,
it would be helpful for us to understand their technology's
capabilities and limitations.
> The unit is supposed to be compensated for + or - 45 degrees of roll
>(which you might expect in a boat), but I found it was not, really.
> The other thing that led me to abandon it was that I find I use the
>DG as my primary heading reference, even though I have GPS, compass,
>etc.
Boats don't roll like airplanes. High roll values are cyclical
meaning about as much roll right as roll left and over relatively
short periods of time. Airplanes can roll over into a sustained turn
that lasts for minutes. I can see where they might claim relative
immunity to high roll values by simply slowing down the response
of their compass with long integration time constants.
Be wary of ANY magnetic compass product that claims "pitch and roll
compensation" . . . it's possible to do this very accurately
but it takes inputs from an attitude gyro and some very
sophisticated computing to do true pitch-roll compensation. Virtually
every compass I've seen that claims some kind of compensation for
pitch-roll uses a magnetic sensor suspended on a gimbal with the notion
that as the vehicle pitches and rolls, the gimbal will allow the
sensor to remain vertical to the earth . . . again, works on boats
but not on airplanes. This gravity-based sensing of a vertical axis
is bogus during a coordinated turn where gravity vertical
remains aligned with airframe vertical.
> It would be fun to experiment with other marine units, but I'm
>afraid I just haven' t the time or money to do it. I had a sailboat a
>few years ago with a flux-gate compass hooked to an autopilot, and all
>worked flawlessly. The cost for a whole instrumentation package
>including the autopilot was about $2500. Most of the newer marine
>products communicate via the NMEA interface -- don't know how close this
>is to anything we use in the air.
Your experience reinforces the my hypothesis for
successful application of electronic magnetic sensors to
aircraft. There are two ways to do it (1) apply relatively
low rate correction signals to a stable platform with a very
long time constant . . . this is how a slaved gyro works.
The magnetic sensor in a slaving system isn't any smarter
than the one for your boat . . . we don't give it a lot of
authority to input correction to the display . . . and we
can even shut it off during high rates of turn.
Method 2 is to combine a turn rate sensor with a magnetic
sensor. Put an electronic display of perceived heading up
with it's value advanced or retarded based on turning rate.
Compare the displayed heading value with measured heading
value and update the displayed heading only when turn rates
are less than 1 degree per second. This system could utilize
a pretty lousy rate sensor . . . if it's deduced heading
drifted as badly as one degree every 10 seconds, this would
make your turn-to-a-heading off by a maximum of 6 degrees
after one minute of turn . . . which would wash out immediately
as soon as the wings level and you can trim to final heading
at tracking rates instead of turning rates.
This would give you a responsive display that behaves like
a slaved DG and uses a computer to deduce when values
received from the magnetic sensor are believable.
Swinging the "compass" is the same for both technologies.
"Stepping around the rose" and tuning out errors is the
only way I know to do it well.
Given the rapid growth of GPS technologies, I think the
magnetic compass needs to go away . . . or take a very
much back seat in how we plan to operate our airplanes
in the future. That doesn't mean a whisky compass wouldn't
be included for use when all GPS is lost but I think it's
time we consider the GPS course signal to be the PRIMARY
(and most useful) steering signal then work on multiple
sources supported by VERY reliable power. Not hard to
do and probably cheaper too.
Bob . . .
________________________________________________________________________________
| Subject: | Re: AMP HDP-22 Pin Crimper |
Richard V. Reynolds wrote:
>
>
> My Apollo UPS ACU connector uses AMP high density pins HDP-22 (.030) AMP
> p/n 748333-4.
>
> The $10 crimp tools do not form the crimp into a "nice .040 inch
> diameter required for easy insertion and more importantly easy removal.
>
> AMP recommends the following Crimp Tools.
> AMP Certi-Crimp p/n 90430-1
> AMP Pro-Crimper II p/n 90800-1
>
> These are very expensive tools $250-$450. Does anyone have an equivalent
> alternative or be willing to lend or rent the AMP tool.
>
*** Check out the aeroelectric web site. There's a link to B&C Specialties.
THEY have the proper tool. It costs about forty bucks. Does a beautiful
job.
- Jerry Kaidor ( jerry(at)tr2.com )
________________________________________________________________________________
| From: | Bill Irvine <wgirvine(at)yahoo.com> |
| Subject: | Re: Low-Volt warning circuits |
> Make your warning light totally independent of the
> power generating source. You need a light that
> flashes any time the bus drops below 13.0 volts
> irrespective of whether your source is generator or
> alternator. You can brew your own per:
> http://209.134.106.21/articles/lvwarn/9021-610.pdf
Great circuit, Bob. But what about those of us with
28 volt machines? What changes do I have to make to
use this circuit?
Bill Irvine
C-310
http://taxes.yahoo.com/
________________________________________________________________________________
| From: | "David Carter" <dcarter(at)datarecall.net> |
| Subject: | Re: Flight Director driver |
Did you buy it new or from salvage? Cost?
David Carter
----- Original Message -----
From: "Richard RIley" <Richard(at)riley.net>
Subject: AeroElectric-List: Flight Director driver
>
> For my attitude indicator I'm using an AIM ARU-48A, a backup gyro out of
an
> F-18/A. It's 110v 400hz 3 phase, and after a LONG search I've found an
> inverter to run it.
>
> In addition to a cageable ball, it has a built in turn coordinator and
slip
> indicator, and a pair of flight director needles. I've gotten the pin out
> from AIM.
>
> Is there any reasonable way to drive the flight director indicators, shy
of
> a very serious autopilot? I understand that the UPSAT GX-60 is shipping
> with roll steering indication output - is that all I need for the
> horizontal needle?
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| From: | "Steve Sampson" <SSampson.SLN21(at)london.edu> |
| Subject: | 3 questions from the UK |
Bob - what a delight to read your book for the first time especially
when I find someone who does not see the point of most breakers and
believes that the automotive industry has somthing to offer! I
understand electricity but most of my interest is in the fabrication
aspects.
4 questions.
1) This is to do with our two languages. You refer to 'fast-ons' (as in
Forest of fast-on ground bus). Are these things that just slide over
'sticky out' tabs and are held in place by friction? If so in the UK
they are called 'receptacles' not that it is of much interest to you. I
presume by their name that is what they are but I could find no mention
of using them in your connector chapter. It was mostly screw on eyelets.
2) I saw a thread the other day where you were commenting why have a
break in the wire at the wing root since the wings would rarely be
removed, just a 8" loop of spare wire. In my situation, I am building an
RV9 it will all go together at home, then the wings be pulled off taken
to the airport re assembled for its first flight. (Quite a common
approach I suspect for a home builder.) I really do not want the thing
parked for days at the airfield whie I try to get it wired. My thought
is that barrier strips just inside the fuselage would make a practical
way of separating the wiring on an occasinal basis. However, I see no
approach like that anywhere in your book. Do you think this a poor idea?
Alternative would be a strip of tabs + fast-ons?
3) Grounding a simple wire - say a nav light. So I crimp an eyelet on
the end of the wire. Now what sort of bolt should I boltit to say a wing
rib with? Brass?
4) And finally corrosion, and this copmes in two parts:
a) In 3 above you will end with a copper wire, a brass bolt(?) and
an ally rib. Does this not set up corrosion issues?
b) And, not part of the wiring circuitry atall. Take an elevator -
made of ally - connected to an ally aeroplane by a steel bolt. Does this
not set up corrosion. Should there be some sort of bonding to 'loosly'
connected parts of the aeroplane?
________________________________________________________________________________
| From: | Bill Irvine <wgirvine(at)yahoo.com> |
| Subject: | CB panel buss bars |
All,
I saw this neat trick for connecting circuit breakers,
and wanted to pass it along, just in case someone
needs it:
A buddy of mine has a Long-EZ with a motly collection
of C/B's (they were free.) They looked good from the
front, but the problem was that they were all of
varying heights and widths in the back, so that the
screw connections weren't in a nice straight line. How
to connect them? A flat strap of brass or copper can
be bent up and down easily enough, but imagine laying
it flat on your workbench and bending it like a snake.
Hmmmm....
He took a piece of 1/4" copper tubing from the
hardware store, laid it flat and carefully bent it
into the required "snake" shape to cover the screws on
the back of the C/B's. Then, using a small steel
block and a hammer, beat the tubing flat. Next, he
bent this "flattened snake" up and down to account for
the different C/B heights, and drilled the appropriate
holes. Slipped on a few short pieces of heat-shrink
to insulate between the breakers, and he was done.
Sure, it took a few tries to get all the bend
allowances right, but it sure was easy and cheap...
maybe 2 bucks and an hour's time, all total. Maybe
everybody else already knows this technique, but I
thought it was such a simple solution to a vexing
problem, that I had to pass it along.
Bill Irvine
C-310
"When life hands you lemons, make lemonade. When life
hands you tomatoes, make Bloody Mary's. It's all
about adapting."
http://taxes.yahoo.com/
________________________________________________________________________________
| From: | Richard RIley <Richard(at)riley.net> |
| Subject: | Re: Flight Director driver |
Got it from my roommate, in exchange for a month's rent, or $400. He got
it salvage. I'm having it rebuilt, that's $800. The inverter is another
$150. All in all, close to the price of a new RC allen 12V, but with
significantly more cool factor.
I also got the 2.5 inch pitot static instruments with it. The altimeter is
very nice, but I'm not sure if I'm going to use the 800 kt. airspeed indicator.
>
>
>Did you buy it new or from salvage? Cost?
>
>David Carter
>
>----- Original Message -----
>From: "Richard RIley" <Richard(at)riley.net>
>To:
>Subject: AeroElectric-List: Flight Director driver
>
>
> >
> > For my attitude indicator I'm using an AIM ARU-48A, a backup gyro out of
>an
> > F-18/A. It's 110v 400hz 3 phase, and after a LONG search I've found an
> > inverter to run it.
> >
> > In addition to a cageable ball, it has a built in turn coordinator and
>slip
> > indicator, and a pair of flight director needles. I've gotten the pin out
> > from AIM.
> >
> > Is there any reasonable way to drive the flight director indicators, shy
>of
> > a very serious autopilot? I understand that the UPSAT GX-60 is shipping
> > with roll steering indication output - is that all I need for the
> > horizontal needle?
> >
> >
>http://www.matronics.com/browselist/aeroelectric-list
> >
> >
>
>
________________________________________________________________________________
| From: | "Curt Reimer" <cgreimer(at)mb.sympatico.ca> |
| Subject: | Is the Stock Lycoming Alternator Usable or Bad news? |
Hi,
I am considering using the stock Lycoming 60A alternator in my RV-6,
strictly for weight and balance reasons. I was planning on a NipponDenso
originally.
Right now my engine is in the shop, so I can't be sure if the stock
alternator will even fit. But assuming it does, is this thing really rated
for 10,000 RPM? Thats what my current pulley ratio would give me. I thought
it would have been designed to turn a lot slower than that in the '70 Cessna
it came out of.
Also, if anyone knows of a equvalent automotive replacement, I'd be grateful
to know the year and model, just in case this one isn't up to snuff. It's a
Motorcraft unit and looks like something you would find in a Ford from the
late sixties.
Its either an ND plus ballast or the stock (free) alternator and less
ballast. Every pound I add to the engine is a pound more I can carry in the
passenger/baggage area. Its sickening I know but thats the way it is with a
wood prop RV-6.
Of course, if there are other reasons not to use this Motorcraft unit, I'm
all ears. But I always assumed everyone switched to the ND strictly because
of weight savings.
thanks,
Curt
----- Original Message -----
From: "Richard V. Reynolds" <rvreynolds(at)macs.net>
Subject: AeroElectric-List: AMP HDP-22 Pin Crimper
>
> My Apollo UPS ACU connector uses AMP high density pins HDP-22 (.030) AMP
> p/n 748333-4.
>
> The $10 crimp tools do not form the crimp into a "nice .040 inch
> diameter required for easy insertion and more importantly easy removal.
>
> AMP recommends the following Crimp Tools.
> AMP Certi-Crimp p/n 90430-1
> AMP Pro-Crimper II p/n 90800-1
>
> These are very expensive tools $250-$450. Does anyone have an equivalent
> alternative or be willing to lend or rent the AMP tool.
>
> Richard Reynolds, Norfolk, VA RV-6A
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| From: | "Richard D. Fogerson" <rickf(at)velocitus.net> |
| Subject: | Batterys in back - Do the wire sizes change |
Hi Bob,
As a follow up to our telephone conversation a few days ago concerning
locating two 17Ahr batteries in the back of my RV3, I was wondering if
any of the wires would increase in size from having to be an additional
4 or 5' longer. The following wires are in question (I will include
there size from Z11):
1) Main Bat/Con to main bus (Z11 - 8AWG)
2) Main Bat/Con solenoid to Bat/Alt Master Sw (Z11 - 22AWG)
3) Aux Bat/Con solenoid to Aux Bat Master Sw (Z11 - 22AWG)
4) Main Bat Bus to Ess Bus (Z11 - 16AWG)
5) Aux Bat Bus to Sw-Boost Pump-on light (Z11 - 22AWG, 3A Fuse)
6) Main Power Dist. Bus to LR3 (Z11 - 18AWG)
7 LR3 to L40 (Z11 - 20AWG, Alt Fld CB 5A)
I got the copy of the aeroelectric book today in good shape, Thanks,
Rick Fogerson.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Low-Volt warning circuits |
>
> > Make your warning light totally independent of the
> > power generating source. You need a light that
> > flashes any time the bus drops below 13.0 volts
> > irrespective of whether your source is generator or
> > alternator. You can brew your own per:
> > http://209.134.106.21/articles/lvwarn/9021-610.pdf
>
>Great circuit, Bob. But what about those of us with
>28 volt machines? What changes do I have to make to
>use this circuit?
R115 changes to 19.6K, 1%
R126 changes to 390 ohms, 5%, 1w
I'll have a "bare board, bare bones" kit for the production
version in a few days (after tax time). . . .
http://209.134.106.21/temp/MVC-081X.JPG
This one will drive the lo-volts warning light
-and- control an aux battery contactor.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: 3 questions from the UK |
>
>
>Bob - what a delight to read your book for the first time especially
>when I find someone who does not see the point of most breakers and
>believes that the automotive industry has somthing to offer! I
>understand electricity but most of my interest is in the fabrication
>aspects.
>
>4 questions.
>
>1) This is to do with our two languages. You refer to 'fast-ons' (as in
>Forest of fast-on ground bus). Are these things that just slide over
>'sticky out' tabs and are held in place by friction? If so in the UK
>they are called 'receptacles' not that it is of much interest to you. I
>presume by their name that is what they are but I could find no mention
>of using them in your connector chapter. It was mostly screw on eyelets.
The chapter on termination was published before I really
sat down and considered the advantages of fast-ons . . .
(AMP trade name) . . . others call them quick disconnect tabs
and receptacles too. They come in various widths (.110, .187,
.210 and .250 inches). You can see more detailed info on
Tyco/AMP's website at
http://catalog.tycoelectronics.com/TE/bin/TE.Menu?M=MENU&ID=10739&LG=1&I=42
and
http://catalog.tycoelectronics.com/TE/bin/TE.Connect?C=122&M=FEAT&LG=1&I=42
Most of my discussions on fast-ons can be found on my website
at:
http://209.134.106.21/articles/faston3.pdf
They'll be added in the next update to the terminals chapter.
>2) I saw a thread the other day where you were commenting why have a
>break in the wire at the wing root since the wings would rarely be
>removed, just a 8" loop of spare wire. In my situation, I am building an
>RV9 it will all go together at home, then the wings be pulled off taken
>to the airport re assembled for its first flight. (Quite a common
>approach I suspect for a home builder.) I really do not want the thing
>parked for days at the airfield whie I try to get it wired. My thought
>is that barrier strips just inside the fuselage would make a practical
>way of separating the wiring on an occasinal basis. However, I see no
>approach like that anywhere in your book. Do you think this a poor idea?
I work really HARD to avoid any kind of threaded fastener
in wiring . . . if you need wing root disconnects, consider
a white nylon product from Amp (mate-n-lock) or Waldom/Molex.
Cessna started using mate-n-locks in production harnesses
in the mid 60's and for all I know, they still do use them.
They've got a good track record.
>3) Grounding a simple wire - say a nav light. So I crimp an eyelet on
>the end of the wire. Now what sort of bolt should I boltit to say a wing
>rib with? Brass?
Clean up all the metal surfaces, and bolt down solid. I like
to use #8 hardware. Once torqued down nice and tight,
paint it.
>4) And finally corrosion, and this copmes in two parts:
> a) In 3 above you will end with a copper wire, a brass bolt(?) and
>an ally rib. Does this not set up corrosion issues?
Stay with tinned terminals held against clean aluminum and
by cad plated steel bolts. This combination has an excellent
track record and it can only get better if you keep the moisture
off it.
> b) And, not part of the wiring circuitry atall. Take an elevator -
>made of ally - connected to an ally aeroplane by a steel bolt. Does this
>not set up corrosion. Should there be some sort of bonding to 'loosly'
>connected parts of the aeroplane?
Corrosion happens when moisture gets between the differential
alloys . . . this is why it's important to put enough pressure
on the torqued down parts to provide "gas tight" connection.
That's why I don't like to use #6 and smaller hardware to
ground things . . . you can't torque a small fastener very
hard. I've had some builders put their grounds down with
AN3 (10-32 hardware) torqued to the high end of the range
for 40,000 psi steel bolts (25 inch pounds). Some folk have
mistaken this for electrical overkill in grabbing the airframe
with a terminated wire, others have properly understood it to
be mechanical protection against corrosion. The better the squash,
the more impervious to moisture.
Download AC43-13 from my website and check out chapter 6
section 1. Paragraph 6.2 talks about combinations of
conditions conducive to corrosion. Availability of
fluids and oxygen are required components that cannot
get into the joint when nicely mated up.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Dimming Circuit |
>
>
>Bob, I am building an RV-8 and was reading (again) the 'Connection. In
>Figure 12-8, you show the schematic for a solid state dimmer, but don't show
>the values for the resistors or the capacitors. I am thinking that I might
>be able to cobble this together as a beginning project. Do you have any
>further details for this or know where I might get some?
There are lots of combinations. Our DIM series dimmers
use 2.5K pot in series with 900 ohm resistor. The resistor
from output to the adjustment pin of the IC is 390
ohms. The capacitors are anything from .1 to 10 uf,
what ever is handy.
Bob . . .
________________________________________________________________________________
| From: | "Ken Brooks" <kdbrv8r(at)charter.net> |
| Subject: | Kroy K3000-PC Shrink Wrap Printer |
Here is a URL to look at the Kroy K3000-PC Shrink Wrap Printer. The price
has "gone up" some, but now sells for $149 with all you need but the shrink
wrap.
http://www.wiremarker.com/k3000_feature.htm
I was thinking that this would make a great purchase for any EAA Chapter for
member use. Use it for your own project first and then donate it to your
chapter. It sure looks like a great way to keep your wires pretty! Thanks
to whomever it was for telling us about it.
Ken Brooks
RV-8
Painting the interior and thinking about wiring
________________________________________________________________________________
| Subject: | SD-8 alternator starting voltage |
| From: | czechsix(at)juno.com |
Someone asked recently whether the SD-8 alternator could come on line
without a battery, and the answer was no. But I'm just wondering how
many volts it needs to come up? If you left your master on and your
battery was dead, but perhaps still showing a very low voltage, would
this be sufficient after hand-propping to get the alternator charging the
battery or would you have to use jumper cables from another battery to
get it going?
--Mark Navratil
Cedar Rapids, Iowa
RV-8A finish kit stuff....
________________________________________________________________________________
| Subject: | Firewall grounding |
| From: | czechsix(at)juno.com |
I'm using a firewall grounding scheme with Bob's grounding block on my
RV. If stainless steel isn't a very good conductor, will this adversely
affect the return path for locally grounded items like nav lights,
landing lights, pitot heat, etc? Should I run some sort of grounding
strap from the grounding block on the stainless firewall to a nearby
longeron for a better ground path?
Thanks,
--Mark Navratil
Cedar Rapids, Iowa
RV-8A finish kit stuff....
________________________________________________________________________________
| From: | "Joe Larson" <jpl(at)showpage.org> |
| Subject: | Kroy K3000-PC Shrink Wrap Printer |
I'm wondering if The List couldn't get one. Everyone chip in $10, one of us
volunteers to be the Label Manager.
To get the labels for your airplane, you'd just have to send a few bucks
(to cover supplies and postage) to this person plus email them a spreadsheet
with the labels you want. For shrink tubing, it looks like the cost is going to
be roughly 30 cents of supplies per label. (110 inches of tubing for $29.95
gives basically 100 labels 1-inch long.)
I don't have a clue how many labels one project would require. 30 cents
at the end of every wire sounds like it would get expensive. I don't know
what other alternative marking methods there are, how much they cost,
nor how many wire ends a typical project may have.
I just emailed these guys to see if I can get some more info out of them.
-Joe
>
> Here is a URL to look at the Kroy K3000-PC Shrink Wrap Printer. The price
> has "gone up" some, but now sells for $149 with all you need but the shrink
> wrap.
>
> http://www.wiremarker.com/k3000_feature.htm
>
> I was thinking that this would make a great purchase for any EAA Chapter for
> member use. Use it for your own project first and then donate it to your
> chapter. It sure looks like a great way to keep your wires pretty! Thanks
> to whomever it was for telling us about it.
________________________________________________________________________________
| From: | Miller Robert <rmiller3(at)earthlink.net> |
| Subject: | Re: RCA connectors |
Are RCA connectors reliable enough? It seems, over time, that the friction hold
of the outer
"flanges" of the connector could spread a bit - decreasing the hold. Would some
sort of
locking connector not be better?
Robert
Charlie and Tupper England wrote:
>
> Tom Barnes wrote:
> >
> >
> > Bob,
> > My marker beacon receiver (RST product) uses an RCA connector for
> > signal input. I couldn't find any documentation on procedures for
> > connecting coax to this, so left to my own imagination, it seems
> > reasonable to solder the center conductor to the center pin and to
> > gather the shield and solder it to the outter part of the connector and
> > possibly put some heat shrink over the soldered shield to hide the mess.
> > Will you pIease comment if this is correct and on anything that I've not
> > considered?
> >
> > Thanks,
> > Tom Barnes
> >
> Tom,
>
> You've got it right on the actual wiring, but instead of
> using shrink to 'hide the mess' you can get an rca connector
> with a metal case. Just slide it on the wire before
> soldering the connections, then crimp (not a technical term
> here) the strain-relief blades over the insulation, then
> screw the metal cover over everything. Radio Shack probably
> has them, but this is one case where you'd really be better
> off finding an electronics supply house that stocks
> Switchcraft brand connectors. You will get pre-tinned solder
> points which will make your life a lot easier if you have
> limited experience with soldering.
>
> Charlie
>
________________________________________________________________________________
| From: | "Joe Larson" <jpl(at)showpage.org> |
| Subject: | EFIS/1 from Blue Mountain Avionics |
I'm wondering how people feel about this product. It looks
totally cool. But talk about single point of failure...
The picture they offer of their installation makes for a very
clean panel, and it offers more functionality than I was
intending to install in my airplane for only a little more money.
Heck -- the cost of their system is only a little more than
the cost of a new HSI.
Comments?
-Joe
________________________________________________________________________________
| Subject: | Re: RCA connectors |
Miller Robert wrote:
>
>
> Are RCA connectors reliable enough? It seems, over time, that the friction hold
of the outer
> "flanges" of the connector could spread a bit - decreasing the hold. Would some
sort of
> locking connector not be better?
*** I've seen more problems with the receptacle for the center pin. You're
right, it's a cheap & dirty connector....
- Jerry Kaidor ( jerry(at)tr2.com )
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: RCA connectors |
>
>
>Are RCA connectors reliable enough? It seems, over time, that the
>friction hold of the outer
>"flanges" of the connector could spread a bit - decreasing the
>hold. Would some sort of
>locking connector not be better?
>Robert
That's why I suggested that my first choice
would be to see if the chassis side of the
connection could be replaced with a TNC,
BNC or SMA connector. If this was not an
option, a machined RCA plug as illustrated
in the pictures I posted would be preferable
to a formed metal plug.
Many early radios in aviation used RCA
connectors for antenna connections and
got along pretty well. With a machined
plug that gets a snug fit on insertion,
I wouldn't loose any sleep over it.
They don't automatically reduce their
grip with time . . .multiple insertion
removal cycles are the biggest wear stresses
and we don't really expect to see a lot
of this in an airplane.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: SD-8 alternator starting voltage |
>
>Someone asked recently whether the SD-8 alternator could come on line
>without a battery, and the answer was no. But I'm just wondering how
>many volts it needs to come up? If you left your master on and your
>battery was dead, but perhaps still showing a very low voltage, would
>this be sufficient after hand-propping to get the alternator charging the
>battery or would you have to use jumper cables from another battery to
>get it going?
If the master has been on for a long, long time . . . the battery
master contactor won't close. In most airplanes, this means
you get out the charger or jumper another battery to the
dead one (this is why I like to wire ground power jacks
to the BATTERY side of the battery master contactor).
If you can still close the contactor, either alternator
will come up and run too.
However, with ALL the nifty ways to notify the last
guy to fly that the master and/or e-bus alternate
feed switches are still on, why would this be a concern?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Firewall grounding |
>
>I'm using a firewall grounding scheme with Bob's grounding block on my
>RV. If stainless steel isn't a very good conductor, will this adversely
>affect the return path for locally grounded items like nav lights,
>landing lights, pitot heat, etc? Should I run some sort of grounding
>strap from the grounding block on the stainless firewall to a nearby
>longeron for a better ground path?
Now consider that the firewall is connected to the fuselage
in many, many places around its periphery. While the steel
is higher in resistance compared to other materials, there
are LOTS of current pathways connected in parallel by
virtue of this "distributed" connection to the fuselage.
Adding any sort of "helping" conductor would be a
very tiny and certainly negligible benefit.
Stainless does have a higher resistance than other
materials for its cross-section . . . but if you've grounded
everything to the single-point ground system, what currents
have to flow in the firewall? . . . only locally grounded items
like landing and taxi lights, pitot heat, nav lights and
strobe power flows through the firewall to the single point
ground.
The firewall as-supplied is entirely adequate to the task.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Batterys in back - Do the wire sizes change |
>
>
>Hi Bob,
>As a follow up to our telephone conversation a few days ago concerning
>locating two 17Ahr batteries in the back of my RV3, I was wondering if
>any of the wires would increase in size from having to be an additional
>4 or 5' longer. The following wires are in question (I will include
>there size from Z11):
>
>1) Main Bat/Con to main bus (Z11 - 8AWG)
>
>2) Main Bat/Con solenoid to Bat/Alt Master Sw (Z11 - 22AWG)
>
>3) Aux Bat/Con solenoid to Aux Bat Master Sw (Z11 - 22AWG)
>
>4) Main Bat Bus to Ess Bus (Z11 - 16AWG)
>
>5) Aux Bat Bus to Sw-Boost Pump-on light (Z11 - 22AWG, 3A Fuse)
>
>6) Main Power Dist. Bus to LR3 (Z11 - 18AWG)
>
>7 LR3 to L40 (Z11 - 20AWG, Alt Fld CB 5A)
You could probably get satisfactory performance
using 4AWG for all of the cranking circuit pathways
in this small an airplane in spite of the aft mounted
battery. However, the weight difference between 4AWG (1/6th
pound/foot) and 2AWG (1/4th pound/foot) for this task is
small . . . probably under 2 pounds. The main bus
feed for an aft mounted battery (item 1) should come
from the hot side of the starter contactor on the
firewall instead of from the battery contactor in the
rear.
All other wires are just fine as you've listed them.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Fig Z16 Rotax diagram questions |
><Gilles.Thesee@ac-grenoble.fr>
>
>Hi, Bob
>
>Re Rotax 912/914 diagram:
>
>Question 1 :
>While studying Fig Z 16 in Rev 10, I'm not sure I really understand the role
>or the 5 A breaker in addition to the fuselink between the masterswitch and
>main bus.
>
>I gather this breaker trips when the crowbar module pulls pin 4 to ground in
>case of overvoltage. It so de-energizes the relay, disconnecting the
>alternator feeder from the battery contactor and main bus.
>Is that correct ?
>
>But then, why the fuselink at the main bus ?
Assuming that the bus is a fuseblock mounted remotely from
the panel mounted breaker and switches, we need to protect
the wire that EXTENDS the bus from fuseblock to breaker.
Hence the fusible link. Some folks have tried to use one of
the fuse slots in the main bus to replace the fusible link and
found that some 5A breakers will open a 30A fuse when the crowbar
hits it . . . so the fusible link is much preferred.
>Question 2 :
>On the same diagram, why does the fuselink at the starter contactor seem to
>be downstream from the feeder ?
That's a real fuse in the form of an ANL or JJS/JJN series
device. The threat to this wire is not from the alternator but
from the battery . . . an alternator is supposed to be incapable
of opening its own b-lead protection (Such is not always the case,
tens of thousands of certified ships have b-lead breakrs designed
to nuisance trip). See:
http://209.134.106.21/articles/anl/anlvsjjs.html
http://209.134.106.21/articles/fuseorcb.html
http://209.134.106.21/articles/fusvsbkr.html
>If this is really so, what protects the feeder between the capacitor and the
>OV relay ?
>Or is it that in case of fault on the feeder, the curent flows from the
>battery to the faulted point ?
You got it. Alternators are inherently current limited.
They cannot damage their own power output wiring.
>I'm not sure I'm interpreting the diagram the right way, so please correct
>me where I'm wrong.
>And please pardon me if I use inadequate technical terms.
Good questions and good communication too . . . I think
we're understanding each other okay.
>Thanks to the knowledge you share with us, the outlines of our future wiring
>slowly emerge.
Please to hear you're making progress. . .
Bob . . .
________________________________________________________________________________
| From: | Mark Steitle <msteitle(at)mail.utexas.edu> |
| Subject: | Re: EFIS/1 from Blue Mountain Avionics |
Nice system, but be aware of Blue Mountain's $695 annual software
maintenance fee.
Mark
>
>I'm wondering how people feel about this product. It looks
>totally cool. But talk about single point of failure...
>
>The picture they offer of their installation makes for a very
>clean panel, and it offers more functionality than I was
>intending to install in my airplane for only a little more money.
>Heck -- the cost of their system is only a little more than
>the cost of a new HSI.
>
>Comments?
>
>-Joe
>
>
________________________________________________________________________________
| From: | "Larry Bowen" <Larry(at)BowenAero.com> |
| Subject: | EFIS/1 from Blue Mountain Avionics |
If monthly chart updates are overkill for your situation, you can change
your subscription to annual for $295/yr. The downside is you also miss
out on the software updates that happen throughout the year, I think.
This is accurate info based on my evesdropping from the back row of the
crowded Blue Mtn booth at SNF. Verify with Blue Mtn. before proceeding.
If you think about all your getting for $58 a month and compare it to
the rest of the industry, it starts to look like a pretty good value,
IMO. Or maybe I've been brainwashed.
-
Larry Bowen
RV-8 fuse with EFIS/1
Larry(at)BowenAero.com
http://BowenAero.com
http://groups.yahoo.com/group/GA-EFIS
> -----Original Message-----
> From: owner-aeroelectric-list-server(at)matronics.com
> [mailto:owner-aeroelectric-list-server(at)matronics.com] On
> Behalf Of Mark Steitle
> Sent: Friday, April 12, 2002 11:31 AM
> To: aeroelectric-list(at)matronics.com
> Subject: Re: AeroElectric-List: EFIS/1 from Blue Mountain Avionics
>
>
> -->
>
> Nice system, but be aware of Blue Mountain's $695 annual software
> maintenance fee.
> Mark
>
> >-->
> >
> >I'm wondering how people feel about this product. It looks totally
> >cool. But talk about single point of failure...
> >
> >The picture they offer of their installation makes for a very clean
> >panel, and it offers more functionality than I was intending
> to install
> >in my airplane for only a little more money. Heck -- the
> cost of their
> >system is only a little more than the cost of a new HSI.
> >
> >Comments?
> >
> >-Joe
> >
> >
>
>
> ===========
> ===========
> ===========
> Search Engine:
> http://www.matronics.com/search
> ===========
>
>
>
>
>
________________________________________________________________________________
| Subject: | Re: EFIS/1 from Blue Mountain Avionics |
The system will soon have virtual out the window view. Mountains, towers,
airports, etc., sort of like sierra flight systems. Also the $695 annual
software maintenance fee is mandatory for the first year only. That includes
all software, charts and approach plates every 28 days. Glad to hear what
others think, I'm flopping back and forth on this one myself.
SteveD
Europa A217
________________________________________________________________________________
| Subject: | Fig Z16 Five More questions |
Bob,
Thank you once again for your time and knowledge.
Things are getting each day a little more clearly defined. Today I was able
to draw a complete diagram of the power distribution.
Some more questions...
> That's a real fuse in the form of an ANL or JJS/JJN series
> device. The threat to this wire is not from the alternator but
> from the battery . . . an alternator is supposed to be incapable
> of opening its own b-lead protection (Such is not always the case,
> tens of thousands of certified ships have b-lead breakrs designed
> to nuisance trip).
Then we'll go for an ANL.
Question 1 :
I suppose your 40 amp model will do for the 18/20 amp Rotax ?
Question 2 :
Due to CG considerations our batterie(s) have to be under the front seats or
just aft of the rear baggage compartment. The actual location shall be
determined after weighing the two other airplanes nearing completion and
having the same engine and CS prop as ours.
According to your answer to Rick (Battery in back), the main bus should be
fed from the hot side of the starter contactor, through the firewall. Is
that correct ?
Question 3 :
Do I need to protect that feeder to the main power bus (ANL, fuselink) ?
Question 4 :
So the busses location should be :
Aux Bat Bus near the auxilliary battery, along with contactor
Main Bat Bus near the main battery, along with contactor
Can the Main Power bus be somewhere behind the panel, since it is fed
through the firewall ?
Question 5 :
Where should the Essential Bus be located ? Near the main Bus, behind the
panel, or rather in the back near the main battery ?
In case those two busses are remote from each other, shouldn't I consider a
fusible link for the feeder and diode between the main and essential busses
?
Thanks you,
Gilles
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Fig Z16 Five More questions |
>
>
>Then we'll go for an ANL.
>
>Question 1 :
>I suppose your 40 amp model will do for the 18/20 amp Rotax ?
I think B*C has a 30Amp that's used with their SD-20
alternator. You can get one from them.
I'm sorry, when you talked about the fusible link in
the output of the alternator, my head was off thinking
about Lycomings.
Z-16 does indeed show an 16AWG fueslink on the end of a 12AWG
feeder. Your choice. I'd have no heartburn with either
approach.
>Question 2 :
>Due to CG considerations our batterie(s) have to be under the front seats or
>just aft of the rear baggage compartment. The actual location shall be
>determined after weighing the two other airplanes nearing completion and
>having the same engine and CS prop as ours.
>According to your answer to Rick (Battery in back), the main bus should be
>fed from the hot side of the starter contactor, through the firewall. Is
>that correct ?
Yes . . . and use 4AWG throughout. The Rotax is in good
shape with the smaller wire.
>Question 3 :
>Do I need to protect that feeder to the main power bus (ANL, fuselink) ?
No.
>Question 4 :
>So the busses location should be :
>Aux Bat Bus near the auxilliary battery, along with contactor
>Main Bat Bus near the main battery, along with contactor
>Can the Main Power bus be somewhere behind the panel, since it is fed
>through the firewall ?
Yes
>Question 5 :
>Where should the Essential Bus be located ? Near the main Bus, behind the
>panel, or rather in the back near the main battery ?
>In case those two busses are remote from each other, shouldn't I consider a
>fusible link for the feeder and diode between the main and essential busses
I'd put it right next to the main bus fuseholder. No protection required
for wires that are very short. If they're side/by/side, then the wires
that connect them are so short as to not be at risk of hard faults.
Bob . . .
________________________________________________________________________________
| From: | Dfmorrow(at)aol.com |
| Subject: | Re: Ritchie electronic compass |
>Boats don't roll like airplanes. High roll values are cyclical
>meaning about as much roll right as roll left and over relatively
>short periods of time. Airplanes can roll over into a sustained turn
>that lasts for minutes. I can see where they might claim relative
>immunity to high roll values by simply slowing down the response
>of their compass with long integration time constants.
This is not entirely true. Sailboats when closehauled to the wind can run
for hours heeled at considerable angles -- 30 degrees or more. The real
difference is that the sailboat is not turning while it is heeled. The
whiskey compass on a sailboat is gimbaled (just like a plane's compass) and
aligns with the force of gravity so that the compass card is always level
with the horizon no matter matter what the angle of heel for the boat. An
airplane turns when it rolls and the compass feels the combined force of
gravity and the centrifugal force of the turn. These forces combine to cause
the compass card in an airplane to align itself level with the horizontal
and longitudinal axes of the airframe. The compass card then rotates to
align north on the card with the projection of the earth's magnet vector onto
the compass card. This causes the familiar "turning error" seen in airplane
compasses. The turning rates for ships and many small boats is very small
and don't generate very large centrifugal forces. Only a high speed motor
boat could achieve heel and turn rates similar to an airplane. I doubt if
high speed boat drivers care very much what their compass is doing during a
hard turn.
An electronic compass would behave very much as a whiskey compass so long as
the magnetic sensor was mounted in gimbals. It would show turning error when
mounted in an airplane. If the magnetic sensor was not mounted in gimbals,
it would show turning error in a sailboat running at a heel angle. So I
would think that any compass intended for marine use would have the magnetic
sensor gimbaled. On their web site Ritchie talks about compensating for "sea
state" i.e. periodic rolling and jerking about with the waves which can
cause compass oscillation if the magnet sensor is not stablized in some way.
In a whiskey compass stabilization is provided by the inertia of the compass
fluid.
________________________________________________________________________________
| Subject: | Fig Z16 Last questions for today ;-) |
Bob,
Thank you so much once more. My knowledge is making giant leaps !
>
> Z-16 does indeed show an 16AWG fueslink on the end of a 12AWG
> feeder. Your choice. I'd have no heartburn with either
> approach.
>
Then I think we'll stay with fuselink.
>
> I'd put it right next to the main bus fuseholder. No protection
required
> for wires that are very short. If they're side/by/side, then the wires
> that connect them are so short as to not be at risk of hard faults.
>
Understand
Last question :
My friend homebuilder is fond of rocker switches, and I'm afraid we won't
easily find a rocker with the same functonnality as your S 700-2-10.
With the Rotax diagram, is there any problem in having just an off/on
masterswitch instead of an off/bat/alt ? My feeling is even in that case, we
better stay with double poles.
Thank you again and again,
Gilles
________________________________________________________________________________
| Subject: | Fig Z16 Last questions for today : Shouldn't have |
asked !
Bob,
Sorry I posted this message BEFORE thinking . The answers ARE in Rev 9.....
Last question :
>
> My friend homebuilder is fond of rocker switches, and I'm afraid we won't
> easily find a rocker with the same functonnality as your S 700-2-10.
> With the Rotax diagram, is there any problem in having just an off/on
> masterswitch instead of an off/bat/alt ?
Rev 9 shows a diagram with that feature.
My feeling is even in that case, we
> better stay with double poles.
Indeed, we do need a two pole switch...
Next time I'll think before typing..
Cheers
Gilles
________________________________________________________________________________
| From: | "Jim Robinson" <jbr(at)hitechnetworks.net> |
| Subject: | Re: faston connectors |
Bob
I need some faston connectors that are .187" for some switches.
What should I look for? I looked in the Digi-Key catalog and there
were a few different types. Is there a designation for the ones you
sell that crimp the connector and the insulation?
Jim
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: faston connectors |
>
>
>Bob
>I need some faston connectors that are .187" for some switches.
>What should I look for? I looked in the Digi-Key catalog and there
>were a few different types. Is there a designation for the ones you
>sell that crimp the connector and the insulation?
Look under the PIDG listing for AMP fast-ons.
Try this:
http://www.digikey.com/scripts/us/dksus.dll?Detail?Ref=10991&Row=76922
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Ritchie electronic compass |
>
> >Boats don't roll like airplanes. High roll values are cyclical
> >meaning about as much roll right as roll left and over relatively
> >short periods of time. Airplanes can roll over into a sustained turn
> >that lasts for minutes. I can see where they might claim relative
> >immunity to high roll values by simply slowing down the response
> >of their compass with long integration time constants.
>
>This is not entirely true. Sailboats when closehauled to the wind can run
>for hours heeled at considerable angles -- 30 degrees or more. The real
>difference is that the sailboat is not turning while it is heeled. The
>whiskey compass on a sailboat is gimbaled (just like a plane's compass) and
>aligns with the force of gravity so that the compass card is always level
>with the horizon no matter matter what the angle of heel for the boat.
Understand . . . this IS a situation where gimbals help. I rented an
airplane once where the ailerons were so far out of rig that I
had to carry a lot of rudder trim to hold a heading . . . the
airplane slogged along with a degree or two of constant roll (and
sideslip) . . . I couldn't belive the shop hadn't fight checked this
ship before putting it back on the line.
> An
>airplane turns when it rolls and the compass feels the combined force of
>gravity and the centrifugal force of the turn. These forces combine to cause
>the compass card in an airplane to align itself level with the horizontal
>and longitudinal axes of the airframe. The compass card then rotates to
>align north on the card with the projection of the earth's magnet vector onto
>the compass card. This causes the familiar "turning error" seen in airplane
>compasses. The turning rates for ships and many small boats is very small
>and don't generate very large centrifugal forces.
Which says that boats don't do "coordinated turns" . . .
>An electronic compass would behave very much as a whiskey compass so long as
>the magnetic sensor was mounted in gimbals. It would show turning error when
>mounted in an airplane. If the magnetic sensor was not mounted in gimbals,
>it would show turning error in a sailboat running at a heel angle. So I
>would think that any compass intended for marine use would have the magnetic
>sensor gimbaled. On their web site Ritchie talks about compensating for "sea
>state" i.e. periodic rolling and jerking about with the waves which can
>cause compass oscillation if the magnet sensor is not stablized in some way.
>In a whiskey compass stabilization is provided by the inertia of the compass
>fluid.
Agreed . . . depending on the sophistication of the software and
possible use of additional sensors for rate and accelerations
along the three axes of the vehicle, a magnetic compass COULD be
crafted to be both stable and accurate under all conditions . . .
unfortunately, these are not at present going to be devices that
sell for $250 . . .
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Last questions for today ;-) |
>
>
>Last question :
>
>My friend homebuilder is fond of rocker switches, and I'm afraid we won't
>easily find a rocker with the same functonnality as your S 700-2-10.
>With the Rotax diagram, is there any problem in having just an off/on
>masterswitch instead of an off/bat/alt ? My feeling is even in that case, we
>better stay with double poles.
The full set of switch functionality features are available in
rockers . . . very popular some years ago with the Glassair folks:
See:
http://content.honeywell.com/sensing/prodinfo/manual/catalog/c30141.pdf
Unfortunately, these critters are not in the same price league as our
S700 series devices. You'd spend more money on a set of switches
than for all the rest of the small components needed to wire the
airplane!
If I recall, the rectifier/regulator supplied with the larger Rotax
machines will run well without a battery on line. You could probably
get by with single pole switches - one for each function. It would
still be a good idea to write up your checklists for battery on first
and off last.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Last questions for today : Shouldn't have asked |
!
><Gilles.Thesee@ac-grenoble.fr>
>
>
>Bob,
>
>Sorry I posted this message BEFORE thinking . The answers ARE in Rev 9.....
>
>Last question :
> >
> > My friend homebuilder is fond of rocker switches, and I'm afraid we won't
> > easily find a rocker with the same functonnality as your S 700-2-10.
> > With the Rotax diagram, is there any problem in having just an off/on
> > masterswitch instead of an off/bat/alt ?
>
>Rev 9 shows a diagram with that feature.
>
>My feeling is even in that case, we
> > better stay with double poles.
>
>Indeed, we do need a two pole switch...
>
>Next time I'll think before typing..
Not a problem - THAT is another option. Use a two pole, OFF-ON
switch to bring battery and alternator on and off together.
In RARE cases where you need to run battery only with alternator
off, you can pull the crowbar ov protection breaker. This
WAS the recommended, low cost, elegant solution before we
identified low cost sources for switches with the nicer
functions like ON-ON-ON progressive transfer.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Stock Lycoming Alternator Usable or Bad news? |
>
>
>Hi,
>
>I am considering using the stock Lycoming 60A alternator in my RV-6,
>strictly for weight and balance reasons. I was planning on a NipponDenso
>originally.
>
>Right now my engine is in the shop, so I can't be sure if the stock
>alternator will even fit. But assuming it does, is this thing really rated
>for 10,000 RPM? Thats what my current pulley ratio would give me. I thought
>it would have been designed to turn a lot slower than that in the '70 Cessna
>it came out of.
I don't know why there would be much difference in operating
speeds. Redlines for production engines run 2500 to 2750,
a very narrow range in the grand scheme of things.
If it came off a production aircraft, the alternator HAS
a service record. I'm not privy to how well the belt driven
alternators have performed on Cessnas . . . you could
check through the service difficulty reports on faa.gov
We KNOW the gear driven alternators are junk but the belt
driven my well have performed better.
>Also, if anyone knows of a equvalent automotive replacement, I'd be grateful
>to know the year and model, just in case this one isn't up to snuff. It's a
>Motorcraft unit and looks like something you would find in a Ford from the
>late sixties.
Cessna was fond of their relationship with Ford's alternators.
We know that the gear driven alternators were specially crafted
for airplanes but it's quite possible that the belt driven machines
were pretty much automotive stock.
>Its either an ND plus ballast or the stock (free) alternator and less
>ballast. Every pound I add to the engine is a pound more I can carry in the
>passenger/baggage area. Its sickening I know but thats the way it is with a
>wood prop RV-6.
Hmmm . . . if I needed ballast, I'd trade out the Ford
alternator for a ND and leave the Prestolite Pig starter
on . . . I would readily trade increased alternator reliability
for reduced starter reliability.
>Of course, if there are other reasons not to use this Motorcraft unit, I'm
>all ears. But I always assumed everyone switched to the ND strictly because
>of weight savings.
Nope . . . at least I wouldn't. B&C's rate of return on ND
alternators due to wear out and/or failure has be phenomenal . . .
Weight reduction is only icing on the cake. I'd suffer
a few more pounds IF it meant that the alternator was
more bullet-proof. But in this case, you get low weight AND
reliability.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Pros and Cons of Battery Bus Remote from Battery |
>
>
>Bob,
>
> Thanks for the input. I have to mull this over a little. I never thought
>that a fusible link would be too slow in responding to a short. You used one
>to connect your E buss. Your about right on the wire count coming off of
>the batteries. E buss, left and right ignition wires off of each battery
>plus maybe 2 or 3 more for a total of about 8 to 9. The biggest being the E
>buss wires (#16).
The only reason to have a fusible link THAT big is if your
e-bus has gotten out of hand. Most designs should be
able to trim e-bus running loads to less than 5 amps
which can be protected with a 22AWG fusible link driving
an 18AWG feeder. If you really gotta have more snort, then
use one of the fuses off the battery bus to protect the
e-bus alternate feed. A fuse is the fastest protection
you can put on this feeder.
>I still don't see the big difference between a fused #14
>battery feed wire carrying 11 amps versus a #16 carrying 7 amps? I do see
>that if a battery feed shorted everything on that buss would fail, but that
>is why I have 2 feeds. Yes, I guess it would be a little better to use
>separate wires, but its damn inconvenient. All that extra wiring and what an
>awful place for fuse blocks.
Why awful? You have batteries back there. There ARE things that
require periodic maintenance. You may go though dozens of
batteries over the lifetime of the airplane and never touch a fuse.
"ALL that wiring?" what's it going to weigh? 20 and 22AWG wire
weighs .008 and .005 pounds per foot! Assuming that you add
30 feet of 20AWG and 30 feet of 22AWG to run the wires back there,
then empty weight of your airplane went up less than 0.5 pounds.
If you have one wire going back there then you have developed
a proper pathway for running any number of wires. You have the
same number of ends to terminate, just in different places.
I don't see a very good tradeoff in dollars, labor and/or
weight savings by avoiding the extra strands . . . besides,
the weight delta isn't going to be that big . . . because
when you take out the .5 pounds max of multiple strands, you
might put in say 8 feet of 14AWG at .015 pounds per
foot or .12 pounds of bus-relocation wire . . . so the
delta is only about .35 pounds max.
Bob . . .
________________________________________________________________________________
| From: | "Curt Reimer" <cgreimer(at)mb.sympatico.ca> |
| Subject: | Re: Stock Lycoming Alternator Usable or Bad news? |
Thanks for the reply Bob.
After checking the RV-List archives I'm pretty sure the old Motorcraft
alternator won't fit under the cowl without having to add a blister for
clearance. So I'll toss it on the scrap heap (or sell it on ebay) and go
with the ND.
And yes, I'm keeping the Prestolite Pig starter, at least until it fails.
When I mentioned the W&B issue to the guy who is overhauling my engine, he
generously offered me a Lycoming GENERATOR since it had the worst
performance/weight ratio in the business. I declined. Talk about pig iron!
Hmmm, but if I had TWO generators, wired in a redundant/failover
configuration, the theoretical reliability would probably exceed even an ND,
and I'd have LOTs of forward ballast....naww, just kidding. Wouldn't touch
those beasts with a 10 foot pole.
thanks,
Curt
________________________________________________________________________________
| Subject: | Re Last questions for..... |
> This
> WAS the recommended, low cost, elegant solution before we
> identified low cost sources for switches with the nicer
> functions like ON-ON-ON progressive transfer.
>
Bob,
Thank you.
Now some more questions, after a deep plunge into past messages.
Question one :
Concerning dual battery switches :
It appears you strongly recommend using SEPARATE masters for the primary and
auxilliary batteries though the reason is still not clear in my mind.
My fear is one can easily forget to switch on the aux bat, or leave it on
after shutting down (He who never forgot a switch throw the first stone...),
resulting in a flat aux battery.
Would it be a good idea to have those two switches combined in one -pardon
me- split rocker ?
This way the pilot is induced to close or open those switches together,
without resorting to an additional item on the chek list :
'Master on' just becomes 'Masters on' etc.
Question two :
In case someone forgot the dual battery masters on and the batteries are
dead flat and unable to energize their contactors, WHERE do you connect your
jumpers to start with external power ?
Isn't it at the AUX battery poles, so that when the alternator comes to life
one can close the MAIN contactor through the E-bus alt feed ?
Otherwise the aux battery could NEVER close it's contactor and could never
get charged.
Please tell me where I'm wrong.
Thank you,
Gilles
________________________________________________________________________________
| From: | "Craig Snively" <craigsn(at)hotmail.com> |
| Subject: | Re: Thermocouple Switch for Blue Mountain EFIS |
Bob,
Ok, I understand what you're suggesting. I've got the hot cylinders
identified to bring the 2 cylinders to the unit, and then switch the 4
cylinders to make the last pair into the EFIS. My question is about the
wiring.
I've got Westach thermocouples for both EGT & CHT. The leads are 4' in
length. So 6 of the 12 wires do not reach into the cockpit area. My
thinking (and where I would like your opinion), is to butt splice copper
wire to the end of each of the thermocouples (rather than put pins on
them and put them into a d-sub connector). This keeps me from having a
d-sub connector in the engine compartment, and I can run the copper
22awg wire into the cockpit where 4 sets will be connected directly to
the rotary switch that you recommended. The other 2 sets will go thru
the box to the db sub connector on the back side of the box. From the
back side of the box, I'll run either EGT or CHT wire to the EFIS
system.
Will this work, or do I really need to have a d-sub connector on the
inbound (front side)?
Thanks
Craig
-----Original Message-----
Bob Says:
Craig Asked:
I'm working on connecting up my EFIS/One from Blue Mountain Avionics
into my existing airplane. I'm looking for a special switch (or
suggestions), connecting my EGT/CHT sensors to the system. The EFIS has
6 inputs for thermocouples, and I have a 6 cylinder Lyc. So I was gonna
put my 3 hottest cylinders, both EGT & CHT (for a total of 6 inputs),
and then use a (and this is where I need the help), a 6 way (6PDT on-on
switch - if there is such a thing). Then I would switch from my 3
hottest cylinders, which I want to monitor most of the time, and to
check the others as needed.
If anyone has a better suggestion, let me know. By the way, I've seen
Bob's thermocouple information in Chap 14 of the current Aeroelectric
Connection.
IF I were to tackle this task on my airplane, here's how
I'd do it:
Put the 2 hottest cylinder CHT/EGT thermocouples onto
2 fixed inputs which uses up 4 of the total.
Run the other pair of inputs to a 4-pole, 4-position
such that thermocouple PAIRS for the other 4 cylinders
can be switched to the "roving" inputs to the EFIS.
Hopefully the thermocouple wires are 20AWG or smaller.
I'd use D-sub connectors with machined pins to make
the interface with individual probes and a harness that
brings all temperature data into the cabin.
The harness needs to be fabricated from the same
kind of thermocouple wire as the probe (type J or K).
I'd bring the bundle to a small enclosure mounting
a two pole, x-position switch for the purpose of
selecting one-of-x thermocouples for display.
Use another d-sub connector at the rear of the enclosure
to bring the probe bundle into the switch and carry the
thermocouple signal away to the instrument.
The interior of the switch box can be wired with
ordinary copper . . . when both sides of the
thermocouple lead are treated with the same
"interfering influence", the errors cancel out.
Thermocouple wire is used to take the signal
from the switch box to the instrument.
Grayhill has a suitable, miniature switch that you
can purchase from Digikey
goto: http://www.digikey.com and enter
71BD30-02-2-AJN as the part number to search.
This switch has two decks of two poles each for
a total of 4 poles. It has an adjustable stop
so that you can limit the throw to 4 positions.
Bob . . .
________________________________________________________________________________
| From: | Gary Liming <gary(at)liming.org> |
Anyone using Lightspeed Engineering's electronic ignition system? It looks
very good on paper, but would like some real useage feedback. I was
thinking of a LASAR sysem instead, but I think I've changed my mind about
that. Any real usage info about LASAR would be appreciated as well.
Thanks,
Gary Liming
(sorry for any list crossover)
________________________________________________________________________________
| From: | Richard RIley <Richard(at)riley.net> |
| Subject: | Re: LSE ignition |
I've used the LSE for about 8 years. Wonderful unit. I've always had one
and a mag, I'm replacing the mag now.
>
>
>Anyone using Lightspeed Engineering's electronic ignition system? It looks
>very good on paper, but would like some real useage feedback. I was
>thinking of a LASAR sysem instead, but I think I've changed my mind about
>that. Any real usage info about LASAR would be appreciated as well.
>
>Thanks,
>
>Gary Liming
>
>(sorry for any list crossover)
>
>
________________________________________________________________________________
| From: | "Richard D. Fogerson" <rickf(at)velocitus.net> |
| Subject: | Location for RMI Encoder |
Hi Bob,
I'm not sure whether to place the RMI Encoder on the Essential Bus or on
one of the Battery Buses. It has flying instruments on it and of course
the xpdr encoder. I will have an AOA instrument so if I lost the
Encoder and therefore the airspeed I would have backup to airspeed with
the AOA.
What are your thoughts?
Rick Fogerson
RV3 Fuselage
Boise, ID
________________________________________________________________________________
| From: | "Craig Snively" <craigsn(at)hotmail.com> |
I've been flying dual LSE ignitions for 4 years and never a lick of
problem with them. Recommended. They just work. And you can use
automobile spark plugs with them, which is what Klaus recommends.
Craig
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Gary
Liming
Subject: AeroElectric-List: LSE ignition
Anyone using Lightspeed Engineering's electronic ignition system? It
looks
very good on paper, but would like some real useage feedback. I was
thinking of a LASAR sysem instead, but I think I've changed my mind
about
that. Any real usage info about LASAR would be appreciated as well.
Thanks,
Gary Liming
(sorry for any list crossover)
=
=
=
http://www.matronics.com/browselist/aeroelectric-list
=
________________________________________________________________________________
| From: | Frank and Dorothy <frankv(at)infogen.net.nz> |
| Subject: | Re: Ritchie electronic compass |
At 03:49 14/04/2002, you wrote:
> >This is not entirely true. Sailboats when closehauled to the wind can run
> >for hours heeled at considerable angles -- 30 degrees or more. The real
> >difference is that the sailboat is not turning while it is heeled. The
> >whiskey compass on a sailboat is gimbaled (just like a plane's compass) and
> >aligns with the force of gravity so that the compass card is always level
> >with the horizon no matter matter what the angle of heel for the boat.
This isn't exactly true... gimbals will align with the net force... that
is, gravity plus centripetal force during a turn. However, a sailboat
remains in approximately (depending on ocean wave height and length) the
same plane during a turn. So, even when it is heeling over, the turn is
still more or less in a horizontal plane. An aircraft does not necessarily
behave like this.
> > An
> >airplane turns when it rolls and the compass feels the combined force of
> >gravity and the centrifugal force of the turn. These forces combine to
> cause
> >the compass card in an airplane to align itself level with the horizontal
> >and longitudinal axes of the airframe. The compass card then rotates to
> >align north on the card with the projection of the earth's magnet vector
> onto
> >the compass card. This causes the familiar "turning error" seen in airplane
> >compasses. The turning rates for ships and many small boats is very small
> >and don't generate very large centrifugal forces.
This all makes sense to me.
> >An electronic compass would behave very much as a whiskey compass so long as
> >the magnetic sensor was mounted in gimbals.
Yup.
> >It would show turning error when
> >mounted in an airplane. If the magnetic sensor was not mounted in gimbals,
> >it would show turning error in a sailboat running at a heel angle. So I
> >would think that any compass intended for marine use would have the magnetic
> >sensor gimbaled. On their web site Ritchie talks about compensating for
> "sea
> >state" i.e. periodic rolling and jerking about with the waves which can
> >cause compass oscillation if the magnet sensor is not stablized in some way.
> >In a whiskey compass stabilization is provided by the inertia of the compass
> >fluid.
>
> Agreed . . . depending on the sophistication of the software and
> possible use of additional sensors for rate and accelerations
> along the three axes of the vehicle, a magnetic compass COULD be
> crafted to be both stable and accurate under all conditions . . .
> unfortunately, these are not at present going to be devices that
> sell for $250 . . .
For those interested in "rolling your own" electronic compass, check out
http://www.fatquarterssoftware.com/toc.htm -- they sell various
magnetometers at a reasonable price.
I think that for an aircraft application, you would probably want 3
magnetometers mounted mutually at right angles. Measuring the angle between
the aircraft's axis and the magnetic vector is (relatively) easy.
Following is a somewhat technical (and perhaps ill-written) explanation of
what's going on. My Masters thesis involves this kind of stuff.
The major problem lies in dealing with the inclination of the magnetic
field... here in NZ, it is 67 degrees from the horizontal. This inclination
varies from place to place round the world. The angle measured between the
aircraft and the field would only be an accurate heading if your aircraft
was pitched up 67 degrees when flying North, or rolled 67 degrees when
flying East or West. For example, if flying horizontally due magnetic
north, the angle between the aircraft and the field would be 67 degrees.
(This inclination, plus the roll angle of the aircraft, is why you need to
over/undershoot when turning to a heading using the whiskey compass).
The inclination can be corrected for if there is another reference vector
available... one candidate is gravity, but it is very difficult to measure
in an aircraft during a turn. Gimbals or the surface of a liquid will tell
you the net force, not the gravitational component. Hence, we use expensive
gyros to provide the other reference vector.
Alternatively, if we *know* that the aircraft is flying straight and level
(i.e. the down force we feel is all due to gravity) then gimbals or a
liquid surface will tell us the direction of gravity and its easy to then
remove the vertical component of the magnetic field. This is essentially
the case with the whiskey compass... if you're flying straight and level,
the compass lies horizontal and points north. If not flying S&L, it will
point in some other direction.
Frank.
________________________________________________________________________________
| From: | "Werner Schneider" <WernerSchneider(at)compuserve.com> |
| Subject: | Re: Location for RMI Encoder |
Hello Richard,
you have to make an list of equipment with what you would like to have on
the essential
and how much current they draw
----- Original Message -----
From: "Richard D. Fogerson" <rickf(at)velocitus.net>
Subject: AeroElectric-List: Location for RMI Encoder
>
> Hi Bob,
>
> I'm not sure whether to place the RMI Encoder on the Essential Bus or on
> one of the Battery Buses. It has flying instruments on it and of course
> the xpdr encoder. I will have an AOA instrument so if I lost the
> Encoder and therefore the airspeed I would have backup to airspeed with
> the AOA.
>
> What are your thoughts?
>
> Rick Fogerson
> RV3 Fuselage
> Boise, ID
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| From: | "Werner Schneider" <WernerSchneider(at)compuserve.com> |
| Subject: | Re: Location for RMI Encoder |
Sorry secon try, got on this bloody mouse pad and off she went!
Out of this list you can easely see how long your equipment might run from
the
essential bus. As the encoder has only a draw between 0.15 and 0.22 A and
if it is the only source for airspeed, I would opt for the essential bus!
Kind regards
Werner (RMI encoder and monitor under construction)
----- Original Message -----
From: "Richard D. Fogerson" <rickf(at)velocitus.net>
Subject: AeroElectric-List: Location for RMI Encoder
>
> Hi Bob,
>
> I'm not sure whether to place the RMI Encoder on the Essential Bus or on
> one of the Battery Buses. It has flying instruments on it and of course
> the xpdr encoder. I will have an AOA instrument so if I lost the
> Encoder and therefore the airspeed I would have backup to airspeed with
> the AOA.
>
> What are your thoughts?
>
> Rick Fogerson
> RV3 Fuselage
> Boise, ID
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Location for RMI Encoder |
>
>
>Hi Bob,
>
>I'm not sure whether to place the RMI Encoder on the Essential Bus or on
>one of the Battery Buses. It has flying instruments on it and of course
>the xpdr encoder. I will have an AOA instrument so if I lost the
>Encoder and therefore the airspeed I would have backup to airspeed with
>the AOA.
>
>What are your thoughts?
>
>Rick Fogerson
>RV3 Fuselage
>Boise, ID
Since you're going to run a second alternator using
the Figure Z-13 architecture, you're no longer bound
by battery capacity to plan endurance during failure
of the main alternator. Depending on your cruise RPM,
you can expect up to 10A of output from the SD-8
alternator while maintaining the e-bus at or above
13.0 volts.
This means that you can run up to 10A of stuff
and hold 100% of the battery reserves for any
other things you want to run during the approach
phase by turning the battery master back ON.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | RE: Thermocouple Switch for Blue Mountain EFIS |
>
>Bob,
>Ok, I understand what you're suggesting. I've got the hot cylinders
>identified to bring the 2 cylinders to the unit, and then switch the 4
>cylinders to make the last pair into the EFIS. My question is about the
>wiring.
>
>I've got Westach thermocouples for both EGT & CHT. The leads are 4' in
>length. So 6 of the 12 wires do not reach into the cockpit area. My
>thinking (and where I would like your opinion), is to butt splice copper
>wire to the end of each of the thermocouples (rather than put pins on
>them and put them into a d-sub connector). This keeps me from having a
>d-sub connector in the engine compartment, and I can run the copper
>22awg wire into the cockpit where 4 sets will be connected directly to
>the rotary switch that you recommended. The other 2 sets will go thru
>the box to the db sub connector on the back side of the box. From the
>back side of the box, I'll run either EGT or CHT wire to the EFIS
>system.
You need to extend thermocouple wires with thermocouple wire.
If you splice to copper at any place other than the instrument
reading the thermocouple, then you've created a new cold-junction
that is remote from the instrument and therefore unaccounted.
>Will this work, or do I really need to have a d-sub connector on the
>inbound (front side)?
You can use any kind of connector you like including butt splices,
but the extension wire needs to match the thermocouples you're
wiring.
Here's a good source for wire.
http://www.omega.com/toc_asp/subsectionSC.asp?subsection=H06&book=Temperature
Bob . . .
________________________________________________________________________________
| From: | "Gordon Robertson" <res0rlvx(at)verizon.net> |
| Subject: | Electronic compass errors |
>An electronic compass would behave very much as a whiskey compass so long
as
>the magnetic sensor was mounted in gimbals. It would show turning error
when
>mounted in an airplane.
I dont understand this. I always thought the turning errors in a whiskey
compass were due to the wieght compensation of the compass to counteract
magnetic dip, and as you turn or accelerate the local g vector is now
different from what the compass was designed for so it registers a turn.
In a flux-gate magnetometer, which is the basis for the electronic
compasses, there is no need to compensate mechanically for the local
magnetic dip. It directly measures that component of the earth's magnetic
field that is aligned with the sensor axes. This should be independent of
the local gravity vector (assuming the compass is NOT gimballed) so
therefore should be immune to turning errors and acceleration errors.
Can somebody enlighten me on why it still shows these errors?
Gordon Robertson
RV8 finishing
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Last questions for..... |
>
>Concerning dual battery switches :
>It appears you strongly recommend using SEPARATE masters for the primary and
>auxilliary batteries though the reason is still not clear in my mind.
>My fear is one can easily forget to switch on the aux bat, or leave it on
>after shutting down (He who never forgot a switch throw the first stone...),
>resulting in a flat aux battery.
What's not clear in my mind is an oft raised concern for "forgetting"
to do this or that . . . the aux battery switch is not the only thing
one might "forget" while piloting an airplane, driving a car, or running
your motorcycle over a challenging dirt course. Every forgotten
detail has its consequences, some worse than others.
This is what check-lists were supposed to fix. Given that the normal
in-flight position for ignition and power switches is to place them
all in the ON position, it seems very unlikely that after you've
started your airplane for the 100th time that you would neglect to
do the task even if you've abandoned the check list. It seems further
unlikely that you would fail to notice it after some period of time
if you have developed a habit of checking over everything on the panel
from time to time during those long cross country flights with nothing
to do but watch the ground go by.
>Would it be a good idea to have those two switches combined in one -pardon
>me- split rocker ?
>This way the pilot is induced to close or open those switches together,
>without resorting to an additional item on the chek list :
>'Master on' just becomes 'Masters on' etc.
Suppose the one switch that does everything fails to do anything?
The one switch does all becomes a single point of failure for the
whole system.
Our aux battery management module CAN be used to automatically
close the aux battery master contactor even when the aux battery
master switch is OFF. This means that NORMAL flight ops call for
closing the aux battery master for engine cranking and then turning
it back OFF after the engine starts. Once the alternator brings the
bus to more than 13.0 volts, the aux battery is brought back on
line by the battery management module. The aux battery is automatically
isolated if the alternator quits (assuming one doesn't "forget"
to turn the switch OFF after the engine starts).
>Question two :
>
>In case someone forgot the dual battery masters on and the batteries are
>dead flat and unable to energize their contactors, WHERE do you connect your
>jumpers to start with external power ?
If you have active notification of low voltage warning on
the panel, the one who "forgets" is going to have to be
blind too.
I like to put ground power connectors on an airplane as a
convenient way to power up the airplane for extended operation
on the ground during maintenance. If you have active low voltage
warning and you treat your batteries as least as good as you
treat your tires, then you're never going to leave the masters
on and the batteries are always going to be ready, willing and
able to go flying when you want to.
I connect ground power to the hot side of the main battery
contactor. This lets you charge the battery without having to
make any other part of the system hot. It also lets you evaluate
the ground power for potential polarity reversal and/or over-
voltage BEFORE the ship's system is powered up.
>Isn't it at the AUX battery poles, so that when the alternator comes to life
>one can close the MAIN contactor through the E-bus alt feed ?
>Otherwise the aux battery could NEVER close it's contactor and could never
>get charged.
If you DO find yourself with a dead aux battery, then you
will indeed have to pull it out for charging or replacement.
Remember, a battery that is left in a discharged state eats
it's own innards at a much faster rate than a charged battery.
The first time you run the battery flat for any period of time
is cause to do a real capacity check on the battery after
it has been recharged. Not being able to close the contactor on
a dead battery is perhaps a GOOD thing . . . a dead battery
is suspect and needs to be investigated for capability.
Bob . . .
________________________________________________________________________________
| From: | "Craig Snively" <craigsn(at)hotmail.com> |
| Subject: | RE: Thermocouple Switch for Blue Mountain EFIS |
I guess I'm missing something here. Sorry about that.
But in the earlier message, and in your Aero Connection, you talk about
building a switching box for the rotary switch, and that I can use
copper wire, on the input and output side of the switch.
>> The interior of the switch box can be wired with
ordinary copper . . . when both sides of the
thermocouple lead are treated with the same
"interfering influence", the errors cancel out.
But in this message, you say:
>> You need to extend thermocouple wires with thermocouple wire.
If you splice to copper at any place other than the instrument
reading the thermocouple, then you've created a new cold-junction
that is remote from the instrument and therefore unaccounted.
So does that mean I can use copper in the box for the rotary switch, or
not? What I am trying to do is take 2 EGT & 2 CHT straight back to the
EFIS (as you suggested), and the other 4 cylinders, EGT & CHT, run thru
the rotary switch, so I can select them as needed.
Again, I'm sorry if I'm misunderstanding your message.
Craig
________________________________________________________________________________
| Subject: | Re: Last questions for..... |
Bob,
Thank you for your lively answer.
Whereas I have lots of questions to ask on the electrical topic, I could
exchange opinions about pilotage and airmanship for hours !
>
> What's not clear in my mind is an oft raised concern for "forgetting"
> to do this or that . . . the aux battery switch is not the only thing
> one might "forget" while piloting an airplane, driving a car, or
running
> your motorcycle over a challenging dirt course. Every forgotten
> detail has its consequences, some worse than others.
Hmm, I'd say "everyting that's not to be forgotten IS going to be
forgotten". We just don't know WHEN.
>
> This is what check-lists were supposed to fix.
Yes. But considering the number of wheels up landings even well trained
professional pilots perform, one may wonder. You do know that under stress
ANY pilot may blow a fuse and forget perfectly obvious things. Yourself once
told us about an airline crew flying an all good airplane into the ground
because they were trying to sort out some switch or light problem.
In my flying club I regularly check out pilots who spend their working time
at the controls of airliners. When the workload is high they DO forget
switches, just like private pilots do.
That's why I was wondering about an additional switch.
But I was just asking. Just asking....;-)
>
> Suppose the one switch that does everything fails to do anything?
> The one switch does all becomes a single point of failure for the
> whole system.
That's why I asked : the first time the master switch is required to DO
something is when I switch it on just before start up. If it fails, well I'm
still on the ground.
Once airborne, is the possiblility of this switch turning off by itself a
likely event ? And I still got my E-bus and always hot battery bars.
Once on the ground again, if it fails to disconnect, then I'l have to get at
the batteries. But I'm on the ground.
>
> Our aux battery management module CAN be used to automatically
> close the aux battery master contactor even when the aux battery
> master switch is OFF. This means that NORMAL flight ops call for
> closing the aux battery master for engine cranking and then turning
> it back OFF after the engine starts. Once the alternator brings the
> bus to more than 13.0 volts, the aux battery is brought back on
> line by the battery management module. The aux battery is
automatically
> isolated if the alternator quits
Most interesting : when is this beast to be offered on your website ?
> (assuming one doesn't "forget" to turn the switch OFF after the engine
starts).
>
Okay, okay, I promise I'll never do !
>
> >Question two :
>
> I connect ground power to the hot side of the main battery
> contactor. This lets you charge the battery without having to
> make any other part of the system hot. It also lets you evaluate
> the ground power for potential polarity reversal and/or over-
> voltage BEFORE the ship's system is powered up.
>
OK
>
> If you DO find yourself with a dead aux battery, then you
> will indeed have to pull it out for charging or replacement.
> Remember, a battery that is left in a discharged state eats
> it's own innards at a much faster rate than a charged battery.
Yes I know
>
> The first time you run the battery flat for any period of time
> is cause to do a real capacity check on the battery after
> it has been recharged. Not being able to close the contactor on
> a dead battery is perhaps a GOOD thing . . . a dead battery
> is suspect and needs to be investigated for capability.
>
Understand
Bob, thank you.
Next time I'll make sure I avoid words like 'forgotten switch' or 'sp...t
rocker switch'. Promise ;-)
Cheers,
Gilles
________________________________________________________________________________
| From: | "Ronnie Brown" <romott(at)adelphia.net> |
| Subject: | Re: Electronic compass errors |
Me either. My PAI vertical card compass does a good job of displaying
heading as long as I am doing 1/2 standard rate turns, and does pretty good
even with standard rate turns. I would think the Richie should do this well
too.
Ronnie Brown
----- Original Message -----
From: "Gordon Robertson" <res0rlvx(at)verizon.net>
Subject: AeroElectric-List: Electronic compass errors
>
> >An electronic compass would behave very much as a whiskey compass so long
> as
> >the magnetic sensor was mounted in gimbals. It would show turning error
> when
> >mounted in an airplane.
>
>
> I dont understand this. I always thought the turning errors in a whiskey
> compass were due to the wieght compensation of the compass to counteract
> magnetic dip, and as you turn or accelerate the local g vector is now
> different from what the compass was designed for so it registers a turn.
> In a flux-gate magnetometer, which is the basis for the electronic
> compasses, there is no need to compensate mechanically for the local
> magnetic dip. It directly measures that component of the earth's magnetic
> field that is aligned with the sensor axes. This should be independent of
> the local gravity vector (assuming the compass is NOT gimballed) so
> therefore should be immune to turning errors and acceleration errors.
>
> Can somebody enlighten me on why it still shows these errors?
>
> Gordon Robertson
> RV8 finishing
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| From: | "Miles McCallum" <milesm(at)avnet.co.uk> |
Anyone know the wattage of a standard nav light bulb<
Cheers
Miles
________________________________________________________________________________
| From: | William Mills <courierboy(at)earthlink.net> |
| Subject: | Re: Nav light bulbs |
>
>Anyone know the wattage of a standard nav light bulb<
>
>Cheers
>
>Miles
Whelen shows two amps each at 14V:
http://www.whelen.com/nondynmc/aviation.htm
See "Position Assemblies"
Bill
________________________________________________________________________________
| Subject: | Fuel pump question |
Hi Bob,
I'm in the process of defining the wiring of our Rotax 914 project.
To date, we are considering a Figure Z 16 system with the addition of an aux
battery and always hot battery busses.
There are points my fellow homebuilder insists upon. One of them is key
switch ignition and starter.
The Rotax 914 is electrically dependant for fuel delivery, having NO
mechanical pump.
Some people run the main pump direct from the regulator, following Rotax
suggestion, but if you lose the regulator you lose the main pump, although
you still got two perfedftly sound batteries.
We wish to have the main pump run on the main hot battery bus any time the
ignition switch is ON.
How can I wire the switch to achieve this goal ?
I know your opinion about this type of switch, but there is nothing I could
do to change his mind.
Thank you
Gilles
________________________________________________________________________________
| From: | Aziz Musa <upperglass(at)yahoo.com> |
Dear Bob,
I read chapter 13 in the Connection more than once.I have an antenna
(radio) problem that you might help with.The airplane is a Long-Ez
with a Terra 960 (mechanical)nav-com.Some days the radio works
crystal clear.Others it either does not transmit clearly (static,
severe garbled),but receives clearly,or it might sometimes transmit
ok but receives badly(garbled).From a short distance with engine not
started or at idle everything works fine.All the above mentioned
problems are when airborne. I have a feeling it is my antenna,and I
like to install a quarter-wave one under the fuselage . Do the 1 inch
groungplane strips have to be 22 inches long? What is the least
acceptable no. of these groundplane strips? Any help concerning all
of the above will be appreciated.Rgrds.Aziz
http://taxes.yahoo.com/
________________________________________________________________________________
| From: | "Gary Casey" <glcasey(at)adelphia.net> |
| Subject: | thermocouple junctions |
<> You need to extend thermocouple wires with thermocouple wire.
If you splice to copper at any place other than the instrument
reading the thermocouple, then you've created a new cold-junction
that is remote from the instrument and therefore unaccounted.<<
So does that mean I can use copper in the box for the rotary switch, or
not? What I am trying to do is take 2 EGT & 2 CHT straight back to the
EFIS (as you suggested), and the other 4 cylinders, EGT & CHT, run thru
the rotary switch, so I can select them as needed.>>
This goes back a long ways, but I distinctly remember that in a power plant
where I once worked the thermocouples were typically run to a local junction
box and spliced to copper wires, from where they were run maybe a half mile
to the control room. The idea was that as long as both + and - connections
were made at the same temperature the errors would cancel out. That
junction was typically outside, so it would change temperature a lot during
the course of a year and I'm sure we didn't recalibrate the instruments
every time the ambient temperature changed.
Gary Casey
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: thermocouple junctions |
>
>< >> You need to extend thermocouple wires with thermocouple wire.
> If you splice to copper at any place other than the instrument
> reading the thermocouple, then you've created a new cold-junction
> that is remote from the instrument and therefore unaccounted.<<
>
>So does that mean I can use copper in the box for the rotary switch, or
>not? What I am trying to do is take 2 EGT & 2 CHT straight back to the
>EFIS (as you suggested), and the other 4 cylinders, EGT & CHT, run thru
>the rotary switch, so I can select them as needed.>>
>
>This goes back a long ways, but I distinctly remember that in a power plant
>where I once worked the thermocouples were typically run to a local junction
>box and spliced to copper wires, from where they were run maybe a half mile
>to the control room. The idea was that as long as both + and - connections
>were made at the same temperature the errors would cancel out. That
>junction was typically outside, so it would change temperature a lot during
>the course of a year and I'm sure we didn't recalibrate the instruments
>every time the ambient temperature changed.
>
>Gary Casey
You can use copper in the box if you use thermocouple
wire to run up to and away from the box. This is where
I WOULD recommend a d-sub connector - wired with
copper inside and t/c wire outside. This places two,
equal but opposite polarity "cold" junctions in
immediate proximity to produce cancelation of the
effects.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Nav light bulbs |
>
>Anyone know the wattage of a standard nav light bulb<
>
>Cheers
>
>Miles
They're about 2A each for 25-27 watts.
Bob . . .
________________________________________________________________________________
| From: | "Mark D. Dickens" <mddickens(at)mindspring.com> |
| Subject: | Capacitors in DC Circuit |
Bob, I have what is probably a stupid question, but I'm just stumped. I
understand the function of capacitance in an AC circuit, but I'm confused
about what they contribute in a DC circuit. As I understand it, once a
capacitor is fully saturated, no further current flows until the capacitor
is shorted (is this right?). So, in looking again at your dimmer circuit
(figure 12-8 in the 'Connection), I wonder what C2 and C7 accomplish.
Thanks
Mark Dickens
RV-8 Fuse SLOWLY coming out of the jig
________________________________________________________________________________
| From: | "Matthew Mucker" <matthew(at)mucker.net> |
| Subject: | Capacitors in DC Circuit |
Mark,
Without having the schematic, I can guess....
Capacitors (and inductors) can be used in a DC power supply circuit to even
out any ripples in the DC voltage. So you'd find these on the output of a
power supply, or the input to a circuit, to provide a buffer for "evening
out" the voltage.
Would that make sense in the context you're seeing them used in?
(And if you can explain the function of capacitance in an AC circuit, I'd be
enlightened. Never did understand that, 'cept maybe in filters....)
-Matt
>
> Bob, I have what is probably a stupid question, but I'm just stumped. I
> understand the function of capacitance in an AC circuit, but I'm confused
> about what they contribute in a DC circuit. As I understand it, once a
> capacitor is fully saturated, no further current flows until the capacitor
> is shorted (is this right?). So, in looking again at your dimmer circuit
> (figure 12-8 in the 'Connection), I wonder what C2 and C7 accomplish.
>
________________________________________________________________________________
| From: | "Mark D. Dickens" <mddickens(at)mindspring.com> |
| Subject: | Re: Capacitors in DC Circuit |
I guess in reality, a capacitor's main function is to act as a noise filter.
In an AC circuit, it's easier to understand that since the voltage changes
so radically. Looking again at the circuit I was referring to, I can see
how having those where he's got them makes sense now. Really, what they
accomplish is a bit of a smoothing out of the aircraft's ground (-) circuit,
particularly at the moment that the circuit is energized.
Thanks
Mark
----- Original Message -----
From: "Matthew Mucker" <matthew(at)mucker.net>
Subject: RE: AeroElectric-List: Capacitors in DC Circuit
>
> Mark,
>
> Without having the schematic, I can guess....
>
> Capacitors (and inductors) can be used in a DC power supply circuit to
even
> out any ripples in the DC voltage. So you'd find these on the output of a
> power supply, or the input to a circuit, to provide a buffer for "evening
> out" the voltage.
>
> Would that make sense in the context you're seeing them used in?
>
> (And if you can explain the function of capacitance in an AC circuit, I'd
be
> enlightened. Never did understand that, 'cept maybe in filters....)
>
> -Matt
>
> >
> > Bob, I have what is probably a stupid question, but I'm just stumped. I
> > understand the function of capacitance in an AC circuit, but I'm
confused
> > about what they contribute in a DC circuit. As I understand it, once a
> > capacitor is fully saturated, no further current flows until the
capacitor
> > is shorted (is this right?). So, in looking again at your dimmer
circuit
> > (figure 12-8 in the 'Connection), I wonder what C2 and C7 accomplish.
> >
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| From: | mprather(at)spro.net |
| Subject: | Re: Capacitors in DC Circuit |
Another way to think about capacitors and inductors is this:
A capacitor is the electrical equivalent of a mechanical spring.
You can put load on it, and it wants to spring back. You can store
potential energy in it. You don't get any filtering action from it
unless you connect a damper (resistor) with it, just like in a car's
suspension. If a car didn't have shocks it would bounce up and down.
If a circuit (filter) doesn't have any resistance (or is low), it
can resonate.
An inductor is like a fly wheel. It takes a while to spin it up/down,
or get current to start or stop. Once you get the electrons moving in
it, because of the b-field generated (inertia - in a flywheel), they
want to keep moving. Inductors can be thought to store kinetic electric
energy. Undamped inductors will have resonance problems as well, though
not usually unless they are coupled with capacitors. Similarly,
flywheels don't usually have resonance problems unless coupled with a
spring (like an engines crankshaft).
The relevance is that very few circuits can be modeled as just DC.
There is always some kind of voltage/current transient going. In
some circuits you don't really care because of either what they are
expected to, and/or what kind of environment in which they operate.
As Matthew Mucker points out, the circuit is likely using capacitors
to function as the active element of filters.
Don't get me going on how electrical circuits are like plumbing...
Matt Prather
----- Original Message -----
From: "Mark D. Dickens" <mddickens(at)mindspring.com>
Date: Monday, April 15, 2002 8:12 am
Subject: AeroElectric-List: Capacitors in DC Circuit
>
> Bob, I have what is probably a stupid question, but I'm just
> stumped. I
> understand the function of capacitance in an AC circuit, but I'm
> confusedabout what they contribute in a DC circuit. As I
> understand it, once a
> capacitor is fully saturated, no further current flows until the
> capacitoris shorted (is this right?). So, in looking again at your
> dimmer circuit
> (figure 12-8 in the 'Connection), I wonder what C2 and C7 accomplish.
>
> Thanks
>
> Mark Dickens
> RV-8 Fuse SLOWLY coming out of the jig
>
>
> _-
>
- The AeroElectric-List Email Forum -
> _-
>
!! NEW !!
> _-
>
List Related Information
> _-
>
=======================================================================
>
>
>
>
>
________________________________________________________________________________
| From: | "Mitch Williams" <mitchw62(at)Prodigy.net> |
| Subject: | Electric upgrade for my 57 cessna....source for the |
60A bus/Copper-brass strap.
Electric Bob and everyone,
The generator failed on our '57 172. We decided we wanted to do
analternator conversion. We looked as Jasco with an STC vs. the Cessna/Ford
on a 337, and decided on the Cessna/Ford. We'll make a 337 with a new
wiring diagram for approval by the FSDO. I think this is a the same
alternator that was original equipment on later model C150s.
I looked up wire sizes in the parts manual for 7155A. Main Wire from
Generator to Regulator to Main Bus to Ammeter to Battery (at starter
terminal) are all #10 gauge copper. According to NEC table 310-16, #10 is
good for about 40 Amps. (35 A system; makes sense.)
To upgrade to 60 Amps, we need to replace these cables with #6 copper.
(#8->55A, #6->75A ). (#6 is also listed in the JASCO installation
package).
Existing fuses: The fuses are all soldered to a solid copper wire bus - also
looks like #10. This is a problem because if we ever have 60A of load on
the system, this bus will overheat and may start a fire. We could limit our
loads to about 40 A, but then what good is a 60 A alternator if you can't
use it. Also, these fuse holders are only rated for 35A, so if one failed
(shorted) it would probably burn up before the 60A breaker opened. Like
dominoes, if we go to 60A, we need to make the whole thing 60A.
Option 1: Replace all fuses with breakers. We have 10 fuses including the
generator fuse. The new system would have 11 breakers, including the 2 we
already ordered (Alternator and Alt Field). We could use 9 additional
pop-out fuses at about $11 each. Connect the breakers to a 60A copper bus.
Build a new support out of aluminum angle and make a new faceplate.
Breakers:
1 Alternator: 60A
2 Alt Field: 5A (pull and pop)
3 NavCom1: 10A
4 NavCom2: 10A
5 Xsponder: 10A
6 MB/Audio Pnl: 5A
7 Turn/bank: 5A
8 Map light: 5A
9 Nav/pos/Dome lights: 10A
10 Landing/Taxi: 25A
11 Strobe: 10A
Option 2:
Build a 2 row system similar to 2002 model 172. One row of Switch/Breakers,
and one row of popouts.
Row 1 (combo switch/breakers PB-W31) These would need to be in one straight
row and could replace the existing: landing-taxi/Pos/Radio switches.
1 Taxi light (15)
2 Land light (15)
3 Pos lights (10)
4 Strobe (10)
5 Master (Existing switch only - no breaker)
Row 2 (pop out breakers PB-W23) These would be installed in the same
location as the existing fuses.
1 Alternator (60)
2 Alt Field (5)
3 NavCom1(10)
4 NavCom2(10)
5 Xsponder(10)
6 MB/Audio Pnl (5)
7 Turn/bank (5)
8 Map light (5)
I'm trying to avoid any major certification issues.
My questions:
1. I need a source for the 60A bus - Copper strap.
mitch
________________________________________________________________________________
| From: | "Mark D. Dickens" <mddickens(at)mindspring.com> |
| Subject: | Re: Capacitors in DC Circuit |
That had to be one of the best explanations I've seen so far....thanks!
----- Original Message -----
From: <mprather(at)spro.net>
Subject: Re: AeroElectric-List: Capacitors in DC Circuit
>
>
> Another way to think about capacitors and inductors is this:
>
> A capacitor is the electrical equivalent of a mechanical spring.
> You can put load on it, and it wants to spring back. You can store
> potential energy in it. You don't get any filtering action from it
> unless you connect a damper (resistor) with it, just like in a car's
> suspension. If a car didn't have shocks it would bounce up and down.
> If a circuit (filter) doesn't have any resistance (or is low), it
> can resonate.
>
> An inductor is like a fly wheel. It takes a while to spin it up/down,
> or get current to start or stop. Once you get the electrons moving in
> it, because of the b-field generated (inertia - in a flywheel), they
> want to keep moving. Inductors can be thought to store kinetic electric
> energy. Undamped inductors will have resonance problems as well, though
> not usually unless they are coupled with capacitors. Similarly,
> flywheels don't usually have resonance problems unless coupled with a
> spring (like an engines crankshaft).
>
> The relevance is that very few circuits can be modeled as just DC.
> There is always some kind of voltage/current transient going. In
> some circuits you don't really care because of either what they are
> expected to, and/or what kind of environment in which they operate.
>
> As Matthew Mucker points out, the circuit is likely using capacitors
> to function as the active element of filters.
>
> Don't get me going on how electrical circuits are like plumbing...
>
> Matt Prather
>
>
> ----- Original Message -----
> From: "Mark D. Dickens" <mddickens(at)mindspring.com>
> Date: Monday, April 15, 2002 8:12 am
> Subject: AeroElectric-List: Capacitors in DC Circuit
>
> >
> > Bob, I have what is probably a stupid question, but I'm just
> > stumped. I
> > understand the function of capacitance in an AC circuit, but I'm
> > confusedabout what they contribute in a DC circuit. As I
> > understand it, once a
> > capacitor is fully saturated, no further current flows until the
> > capacitoris shorted (is this right?). So, in looking again at your
> > dimmer circuit
> > (figure 12-8 in the 'Connection), I wonder what C2 and C7 accomplish.
> >
> > Thanks
> >
> > Mark Dickens
> > RV-8 Fuse SLOWLY coming out of the jig
> >
> >
> > _-
> >
> - The AeroElectric-List Email Forum -
> > _-
> >
> !! NEW !!
> > _-
> >
> List Related Information
> > _-
> >
> =======================================================================
> >
> >
> >
> >
> >
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
>
>Dear Bob,
>I read chapter 13 in the Connection more than once.I have an antenna
>(radio) problem that you might help with.The airplane is a Long-Ez
>with a Terra 960 (mechanical)nav-com.Some days the radio works
>crystal clear.Others it either does not transmit clearly (static,
>severe garbled),but receives clearly,or it might sometimes transmit
>ok but receives badly(garbled).From a short distance with engine not
>started or at idle everything works fine.All the above mentioned
>problems are when airborne.
> I have a feeling it is my antenna,and I
>like to install a quarter-wave one under the fuselage
I'm suspicious of this being purely and antenna problem
but it's easy to discount:
> Do the 1 inch
>groungplane strips have to be 22 inches long? What is the least
>acceptable no. of these groundplane strips? Any help concerning all
>of the above will be appreciated.
Yes, performance of constructed ground planes is strongly
influenced by the length of the "radials" They don't have to
be flat . . . i.e. they can curl up the fuselage contours
but total length should be equal to the height of the
antenna you're "grounding" . . . 4 radials is about the minimum
and there are rapidly diminishing returns on investment over
8 radials.
I'd check the final installation for low SWR over the
communications band . . . 3:1 or lower from 118 to 135
MHz. Further, make arrangements to plug a hand-held
transceiver into this antenna under conditions wherein
the panel mounted transceiver is giving you problems.
This will help separate out the antenna as a root cause.
Bob . . .
________________________________________________________________________________
| From: | "Mike Nellis" <mike(at)bmnellis.com> |
| Subject: | Re: Capacitors in DC Circuit |
You're right, that was a pretty good explanation. Those of us that don't
know much about electrons wouldn't know if it was accurate or not but it
sure sounds good. When I was an ET in the Navy and struggling with
this stuff (I still struggle with it that's why I left the field) everyone
always said, "it's just like plumbing". I figured I knew plumbing but
somehow I never figured out the electricity part except I turned out to be
pretty good at soldering.
Based on the explanation though, is that why we see the capacitors on top
of the electric motors? The cap stores up all that potential energy and
then dumps it all to the shorted inductor to get it spinning up real fast?
Mike Nellis - http://bmnellis.com
Georgetown, TX
Waiting to start Fuselage
RV6 N699BM Reserved
1947 Stinson 108-2 N9666K
>
> That had to be one of the best explanations I've seen so far....thanks!
> ----- Original Message -----
> From: <mprather(at)spro.net>
> To:
> Subject: Re: AeroElectric-List: Capacitors in DC Circuit
>
>
> >
> >
> > Another way to think about capacitors and inductors is this:
> >
> > A capacitor is the electrical equivalent of a mechanical spring.
> > You can put load on it, and it wants to spring back. You can store
> > potential energy in it. You don't get any filtering action from it
> > unless you connect a damper (resistor) with it, just like in a car's
> > suspension. If a car didn't have shocks it would bounce up and down.
> > If a circuit (filter) doesn't have any resistance (or is low), it
> > can resonate.
> >
> > An inductor is like a fly wheel. It takes a while to spin it up/down,
> > or get current to start or stop. Once you get the electrons moving in
> > it, because of the b-field generated (inertia - in a flywheel), they
> > want to keep moving. Inductors can be thought to store kinetic electric
> > energy. Undamped inductors will have resonance problems as well, though
> > not usually unless they are coupled with capacitors. Similarly,
> > flywheels don't usually have resonance problems unless coupled with a
> > spring (like an engines crankshaft).
> >
> > The relevance is that very few circuits can be modeled as just DC.
> > There is always some kind of voltage/current transient going. In
> > some circuits you don't really care because of either what they are
> > expected to, and/or what kind of environment in which they operate.
> >
> > As Matthew Mucker points out, the circuit is likely using capacitors
> > to function as the active element of filters.
> >
> > Don't get me going on how electrical circuits are like plumbing...
> >
> > Matt Prather
> >
> >
> > ----- Original Message -----
> > From: "Mark D. Dickens" <mddickens(at)mindspring.com>
> > Date: Monday, April 15, 2002 8:12 am
> > Subject: AeroElectric-List: Capacitors in DC Circuit
> >
> > >
> > > Bob, I have what is probably a stupid question, but I'm just
> > > stumped. I
> > > understand the function of capacitance in an AC circuit, but I'm
> > > confusedabout what they contribute in a DC circuit. As I
> > > understand it, once a
> > > capacitor is fully saturated, no further current flows until the
> > > capacitoris shorted (is this right?). So, in looking again at your
> > > dimmer circuit
> > > (figure 12-8 in the 'Connection), I wonder what C2 and C7 accomplish.
> > >
> > > Thanks
> > >
> > > Mark Dickens
> > > RV-8 Fuse SLOWLY coming out of the jig
> > >
> > >
> > > _-
> > >
> > - The AeroElectric-List Email Forum -
> > > _-
> > >
> > !! NEW !!
> > > _-
> > >
> > List Related Information
> > > _-
> > >
> > =======================================================================
> > >
> > >
> > >
> > >
> > >
> >
> >
> >
> >
>
>
http://www.matronics.com/browselist/aeroelectric-list
>
>
________________________________________________________________________________
| From: | "Cy Galley" <cgalley(at)qcbc.org> |
I would look at the coax connections. Is there one that can get wet? One
might be loose. If you have any extra length to the cable, cutting off the
end and crimping on a new end many times will help.
Cy Galley, TC - Chair, Emergency Aircraft Repair, Oshkosh
Editor, EAA Safety Programs
cgalley(at)qcbc.org or experimenter(at)eaa.org
Always looking for articles for the Experimenter
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckolls(at)kscable.com>
Subject: Re: AeroElectric-List: antenna
>
>Dear Bob,
>I read chapter 13 in the Connection more than once.I have an antenna
>(radio) problem that you might help with.The airplane is a Long-Ez
>with a Terra 960 (mechanical)nav-com.Some days the radio works
>crystal clear.Others it either does not transmit clearly (static,
>severe garbled),but receives clearly,or it might sometimes transmit
>ok but receives badly(garbled).From a short distance with engine not
>started or at idle everything works fine.All the above mentioned
>problems are when airborne.
> I have a feeling it is my antenna,and I
>like to install a quarter-wave one under the fuselage
I'm suspicious of this being purely and antenna problem
but it's easy to discount:
> Do the 1 inch
>groungplane strips have to be 22 inches long? What is the least
>acceptable no. of these groundplane strips? Any help concerning all
>of the above will be appreciated.
Yes, performance of constructed ground planes is strongly
influenced by the length of the "radials" They don't have to
be flat . . . i.e. they can curl up the fuselage contours
but total length should be equal to the height of the
antenna you're "grounding" . . . 4 radials is about the minimum
and there are rapidly diminishing returns on investment over
8 radials.
I'd check the final installation for low SWR over the
communications band . . . 3:1 or lower from 118 to 135
MHz. Further, make arrangements to plug a hand-held
transceiver into this antenna under conditions wherein
the panel mounted transceiver is giving you problems.
This will help separate out the antenna as a root cause.
Bob . . .
http://www.matronics.com/browselist/aeroelectric-list
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: upgrade for my 57 cessna |
>
>
>Electric Bob and everyone,
>
>The generator failed on our '57 172. We decided we wanted to do
>analternator conversion. We looked as Jasco with an STC vs. the Cessna/Ford
>on a 337, and decided on the Cessna/Ford. We'll make a 337 with a new
>wiring diagram for approval by the FSDO. I think this is a the same
>alternator that was original equipment on later model C150s.
>
>I looked up wire sizes in the parts manual for 7155A. Main Wire from
>Generator to Regulator to Main Bus to Ammeter to Battery (at starter
>terminal) are all #10 gauge copper. According to NEC table 310-16, #10 is
>good for about 40 Amps. (35 A system; makes sense.)
>
>To upgrade to 60 Amps, we need to replace these cables with #6 copper.
>(#8->55A, #6->75A ). (#6 is also listed in the JASCO installation
>package).
>
>Existing fuses: The fuses are all soldered to a solid copper wire bus - also
>looks like #10. This is a problem because if we ever have 60A of load on
>the system, this bus will overheat and may start a fire. We could limit our
>loads to about 40 A, but then what good is a 60 A alternator if you can't
>use it. Also, these fuse holders are only rated for 35A, so if one failed
>(shorted) it would probably burn up before the 60A breaker opened. Like
>dominoes, if we go to 60A, we need to make the whole thing 60A.
>
>Option 1: Replace all fuses with breakers. We have 10 fuses including the
>generator fuse. The new system would have 11 breakers, including the 2 we
>already ordered (Alternator and Alt Field). We could use 9 additional
>pop-out fuses at about $11 each. Connect the breakers to a 60A copper bus.
>Build a new support out of aluminum angle and make a new faceplate.
>
>I'm trying to avoid any major certification issues.
If the existing fuse holders are working for you then in the
interest of stirring up the least amount of "mud", I'd
leave all the fuseholders as is. Wire the new alternator
directly to the hot side of the starter contactor by
way of an ANL-60 current limiter.
>My questions:
>
>1. I need a source for the 60A bus - Copper strap.
If you're going to open that can of worms, then use any
breaker your AI thinks he can sell on a 337. You can buy
brass strip from a lot of sources like Home Depot, Lowes,
Hobby-Lobby, etc. You need some sheet brass 3/8 to 1/2
inch wide by .05 to 03 thick depending on width. I've
cut bus bars out of brass kick-shields for doors that I've
purchased from a hardware store. It's not critical.
If you go breakers, make the alternator breaker a 75A
device lest you become victim to the same philosophy
that fitted tens of thousands of airplanes with breakers
designed to nuisance trip.
See: http://209.134.106.21/articles/fuseorcb.html
http://209.134.106.21/articles/fusvsbkr.html
http://209.134.106.21/articles/neveragain/neveragain.html
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Capacitors in DC Circuit |
Bob, I have what is probably a stupid question, but I'm just stumped. I
understand the function of capacitance in an AC circuit, but I'm confused
about what they contribute in a DC circuit. As I understand it, once a
capacitor is fully saturated, no further current flows until the capacitor
is shorted (is this right?). So, in looking again at your dimmer circuit
(figure 12-8 in the 'Connection), I wonder what C2 and C7 accomplish.
>Another way to think about capacitors and inductors is this:
>
>A capacitor is the electrical equivalent of a mechanical spring.
>You can put load on it, and it wants to spring back.
>An inductor is like a fly wheel. It takes a while to spin it up/down,
>or get current to start or stop. Once you get the electrons moving in
>it, because of the b-field generated (inertia - in a flywheel), they
>want to keep moving.
Hmmm . . . sorta . . . If one were to draw mechanical
parallels with electrical parts, the capacitor is MASS
(resist change in voltage), the inductor is SPRING (resist
change in tension) and resistors are FRICTION (do nothing
but waste energy).
>The relevance is that very few circuits can be modeled as just DC.
>There is always some kind of voltage/current transient going. In
>some circuits you don't really care because of either what they are
>expected to, and/or what kind of environment in which they operate.
>
>As Matthew Mucker points out, the circuit is likely using capacitors
>to function as the active element of filters.
One includes capacitors and inductors in circuits only
when there are DYNAMIC features to be controlled. If the
circuit is purely stable DC, inclusion of reactive components
like inductors and capacitors will have no effect.
The capacitors cited in the originating message are used
to fool the integrated circuit dimming regulator in believing
that there are no wires connected to the input and output
leads. This is necessary because the IC has a habit of using
significant INDUCTANCE of long lead wires as components of
an oscillator (here's a case where reactance makes the
system LESS stable). Sooooo . . . we add the capacitors to
provide strong resistance to dynamic changes in voltage at
the IC's terminals and the system becomes stable.
In the case of using an inductor and capacitor as a noise
filter (see: http://209.134.106.21/articles/filter/filter.html )
we configure the inductor in series with the power and facing
the noise source (a variable current that sees a large
impedance) and a capacitor from power supply to ground (a
device that resists changes in voltage thereby increasing
effectiveness of the series inductor in smoothing transient
effects (noise) trying to make their way through to the
victim.
These are but two examples of reactive components in dynamic
situations.
See
http://www.st-and.ac.uk/~www_pa/Scots_Guide/info/signals/complex/react.html
and
http://www.sweethaven.com/acee/forms/toc01.htm
There are also cases where the combinations are scaled
with respect to each other so as to be responsive to (or
resonate) with an applied signal. For example, hand a weight on
a spring. Pull down an let loose. The combination will oscillate at
some fixed frequency based on the combination of SPRING rate
and MASS that ultimately degrades to zero because of resistance
due to FRICTION.
see: http://www.phys.unsw.edu.au/~jw/LCresonance.html
Bob . . .
________________________________________________________________________________
| From: | mprather(at)spro.net |
| Subject: | Re: Capacitors in DC Circuit |
I guess this goes to show why electricity is hard to understand. Two
models that draw parallels to the mechanical world, and I would argue
that both are useful for improving understanding.
My problem (if I may be so bold as to express one...) with Mr Nuckolls'
model is that I view capacitors as storing energy (in the form of charge
potential) in a static state. The energy is not in motion. Kind of
like a spring stores motion potential) when perturbed from its relaxed
state. And can hold it for basically forever (given an ideal spring).
Mr Nuckolls says that a capacitor is more like MASS in a physical
system, but I would argue that MASS is more like an inductor. It
resists motion in a different way. One can instantly apply lots of
force (voltage to an inductor) to a MASS but it resists moving very
quickly (increasing current). Slows the flow.
On a capacitor, its difficult to change the voltage (force) on it very
quickly because (like a spring) you have to displace the input. It
doesn't slow the flow (resist changes in current). You can
instantaneosly move its input a displacement (put a large current on
it), but you can't instantaneosly put a force (voltage) on it.
So I guess I think about the active components in reverse from Mr
Nuckolls. We agree on the role of resistors, however. It must be that
we think about the existence of energy in different ways.
I admit, however, that even though my model got me through a BSEE, I
have far less experience using it.... Its worth what you paid for it.
:)
Regards,
Matt Prather
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckolls(at)kscable.com>
Date: Monday, April 15, 2002 1:03 pm
Subject: AeroElectric-List: Re: Capacitors in DC Circuit
>
> Bob, I have what is probably a stupid question, but I'm just
> stumped. I
> understand the function of capacitance in an AC circuit, but I'm
> confusedabout what they contribute in a DC circuit. As I understand
> it, once a
> capacitor is fully saturated, no further current flows until the
> capacitoris shorted (is this right?). So, in looking again at your
> dimmer circuit
> (figure 12-8 in the 'Connection), I wonder what C2 and C7 accomplish.
>
>
> >Another way to think about capacitors and inductors is this:
> >
> >A capacitor is the electrical equivalent of a mechanical spring.
> >You can put load on it, and it wants to spring back.
>
>
>
>
> >An inductor is like a fly wheel. It takes a while to spin it
> up/down,>or get current to start or stop. Once you get the
> electrons moving in
> >it, because of the b-field generated (inertia - in a flywheel), they
> >want to keep moving.
>
>
>
> Hmmm . . . sorta . . . If one were to draw mechanical
> parallels with electrical parts, the capacitor is MASS
> (resist change in voltage), the inductor is SPRING (resist
> change in tension) and resistors are FRICTION (do nothing
> but waste energy).
>
>
> >The relevance is that very few circuits can be modeled as just DC.
> >There is always some kind of voltage/current transient going. In
> >some circuits you don't really care because of either what they are
> >expected to, and/or what kind of environment in which they operate.
> >
> >As Matthew Mucker points out, the circuit is likely using capacitors
> >to function as the active element of filters.
>
> One includes capacitors and inductors in circuits only
> when there are DYNAMIC features to be controlled. If the
> circuit is purely stable DC, inclusion of reactive components
> like inductors and capacitors will have no effect.
>
> The capacitors cited in the originating message are used
> to fool the integrated circuit dimming regulator in believing
> that there are no wires connected to the input and output
> leads. This is necessary because the IC has a habit of using
> significant INDUCTANCE of long lead wires as components of
> an oscillator (here's a case where reactance makes the
> system LESS stable). Sooooo . . . we add the capacitors to
> provide strong resistance to dynamic changes in voltage at
> the IC's terminals and the system becomes stable.
>
> In the case of using an inductor and capacitor as a noise
> filter (see: http://209.134.106.2 )
> we configure the inductor in series with the power and facing
> the noise source (a variable current that sees a large
> impedance) and a capacitor from power supply to ground (a
> device that resists changes in voltage thereby increasing
> effectiveness of the series inductor in smoothing transient
> effects (noise) trying to make their way through to the
> victim.
>
> These are but two examples of reactive components in dynamic
> situations.
>
> See
> http://www.st-
> and.ac.uk/~www_pa/Scots_Guide/info/signals/complex/react.html
> and
>
> http://www.sweethaven.co
>
> There are also cases where the combinations are scaled
> with respect to each other so as to be responsive to (or
> resonate) with an applied signal. For example, hand a weight on
> a spring. Pull down an let loose. The combination will
> oscillate at
> some fixed frequency based on the combination of SPRING rate
> and MASS that ultimately degrades to zero because of resistance
> due to FRICTION.
>
> see: http://www.phys.unsw.edu.au/~jw/LCresonance.html
>
> Bob . . .
>
>
> _-
>
- The AeroElectric-List Email Forum -
> _-
>
!! NEW !!
> _-
>
List Related Information
> _-
>
=======================================================================
>
>
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Capacitors in DC Circuit |
>
>You're right, that was a pretty good explanation. Those of us that don't
>know much about electrons wouldn't know if it was accurate or not but it
>sure sounds good. When I was an ET in the Navy and struggling with
>this stuff (I still struggle with it that's why I left the field) everyone
>always said, "it's just like plumbing". I figured I knew plumbing but
>somehow I never figured out the electricity part except I turned out to be
>pretty good at soldering.
>
>Based on the explanation though, is that why we see the capacitors on top
>of the electric motors? The cap stores up all that potential energy and
>then dumps it all to the shorted inductor to get it spinning up real fast?
No, here the capacitor pulls another magic trick in
dynamic current flows out of the hat . . .
The easiest AC motors to build, and the most efficient,
use polyphase power (years ago, you could buy 2-phase
power from some suppliers - two AC power lines that
were 90 degrees displaced) with the most common being
3-phase (three power lines displaced by 120 degrees).
Application of 3-phase power to a stator winding (not
unlike the stator in your alternator) produces a
magnetic field within the stators interior that spins
at some sub-multiple of applied power's frequency.
A two-pole motor supplied with 60Hz power produces
3600 RPM field. A six-pole motor produces a 1200 RPM
field, etc.
Put a "squirrel cage" rotor in this spinning field
and it gets dragged along at some speed just below
the synchronous speed for that particular motor.
What's a mother to do when you have only single
phase power delivered to the back of your house?
There are ways to fool a motor into believing that
more than one phase is present. Simple motors
like fans use SHADED POLE motors. Small motors
like blowers in your furnace use a START WINDING's
inductance and resistance combined with a
capacitor to provide a phase shift in the second
winding and generate a rotating field in a single
phase stator. Sometimes you see two capacitors . . .
one for starting and one for running on larger
motors like those used on air compressors.
Bob . . .
________________________________________________________________________________
| From: | deltab(at)erols.com |
| Subject: | Re: Lead acid storage batteries. |
Here's one from the DOE. It wasn't one of the ones I was hoping
for. The do use the words "primer" in the title for those
interested. I'm beginning to think that what I was looking for was
in a couple IEEE documents which aren't normally available to the
public. The DOE had standards for SLA batteries, but it was just
ordering information, not how they worked or care and feeding. Now
to find something on isolation of redundant electrical systems.
<<http://tis.eh.doe.gov/techstds/standard/hdbk1084/hdbk1084.pdf>>
Bernie C.
"Robert L. Nuckolls, III" wrote:
>
>
> >
> >For personal enrichment: this is how the other half lives.
> >(hint:download first)
> >
> ><<http://m4ruby.ece.jhu.edu/library/nstm/223v1r2a.pdf>>
> >
> >The DOE had some links to valved SLA batteries. I'll see if the links
> >still exist.
> >
> >
> >Bernie C.
>
> Neat document. I'll retain it for reference. It's
> interesting to see how much time and effort an organization
> can put into maintaining and understanding batteries when
> the future of ship and crew may depend on getting the last
> watt-hour of energy stored . . . and then compare efforts
> to another institution that has recorded perhaps thousands
> of dark-n-stormy-night stories about what they experienced
> when their battery fell short of basic needs because
> it was mis-understood, abused and ignored.
>
> Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Capacitors in DC Circuit |
>
>I guess this goes to show why electricity is hard to understand. Two
>models that draw parallels to the mechanical world, and I would argue
>that both are useful for improving understanding.
>
>My problem (if I may be so bold as to express one...) with Mr Nuckolls'
>model is that I view capacitors as storing energy (in the form of charge
>potential) in a static state. The energy is not in motion. Kind of
>like a spring stores motion potential) when perturbed from its relaxed
>state. And can hold it for basically forever (given an ideal spring).
>
>Mr Nuckolls says that a capacitor is more like MASS in a physical
>system, but I would argue that MASS is more like an inductor. It
>resists motion in a different way. One can instantly apply lots of
>force (voltage to an inductor) to a MASS but it resists moving very
>quickly (increasing current). Slows the flow.
Here's the rational for the analogy:
You can store energy on a MASS by simply elevating
it to a higher level. The act of picking up a 10#
weight from the floor and putting it on the table
stores 30 lb-ft of energy on the MASS. It sits there
with that potential for ever and ever until you
bring some effect along to disturb it. Similarly,
you charge a capacitor and assuming no leakage losses,
it too will retain that energy in a static condition
as long as no external forces come along.
The MASS has inertia . . . applying a force to a
mass in a frictionless environment accelerates
the mast to some new velocity thereby altering
its energy level. It will resist that by
"pushing back" with a force equal to the
accelerating force insofar as the force can
increase in velocity. Similarly, a capacitor
"pushes back", resisting change in voltage so
long as current is being supplied from some source
of voltage greater than the present charge on the
capacitor. When the two voltages are equal,
transfer of energy ceases and the energy stored
on the capacitor stable until acted upon by
some new force.
Hence the suggestion that a capacitor is very
MASS-like in its ability to both react to and
store energy.
A spring stores energy only if you apply and hold
an external force. Like the inductor which stores
energy only while current flows through it from
and external source, the spring cannot in and of
itself store energy without help from the outside.
Remove the outside help from either device stored
energy is lost.
From a mathematical perspective, one
could label inductance and capacitance with
any name one likes as long as the sign of
the phase angle assigned to that component
is correct. Guess it was all up to our
teachers . . .
Bob . . .
________________________________________________________________________________
| From: | "Bruce Banks" <b2banks(at)earthlink.net> |
| Subject: | Re: thermocouple junctions |
Working as an instrumentation and control Engineer for many years both in
Gas, Petro Chemical and Power plants. We always ran the t/c extension wire
direct from the instrument to the control room without stopping, then
terminating at our panel through a cold-juction compensator (referenced to
32 Deg. F). If we had long distances we would use a muti-plexer, this would
allow us to run just
two wires back to the control room where we would be able to select which
t/c we wanted to look at. Any terminal not made of the same material as the
Thermocouple itself (Type J Iron-constantane and Type K cromel-alumel. )
(There are other types depending on the temperature being read. ) No reason
not to run from the engine t/c sensors back to the Temp Indicator. If you
terminate on standard terminals, then you will be reading the ambient
temperature at the point of junction. Hope this helps. One mans opinion
anyway. (it works for us) Thanks The Banks Brothers Bruce
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Fuel pump question |
><Gilles.Thesee@ac-grenoble.fr>
>
>Hi Bob,
>
>I'm in the process of defining the wiring of our Rotax 914 project.
>To date, we are considering a Figure Z 16 system with the addition of an aux
>battery and always hot battery busses.
>There are points my fellow homebuilder insists upon. One of them is key
>switch ignition and starter.
>The Rotax 914 is electrically dependant for fuel delivery, having NO
>mechanical pump.
>Some people run the main pump direct from the regulator, following Rotax
>suggestion, but if you lose the regulator you lose the main pump, although
>you still got two perfedftly sound batteries.
>
>We wish to have the main pump run on the main hot battery bus any time the
>ignition switch is ON.
>How can I wire the switch to achieve this goal ?
There are no terminals on the contemporary OFF-L-R-BOTH-START
magneto switches that would allow you to do this. I think there
are some switches used on some ultra-lights that have a BAT (battery)
and ACC (accessory) terminals that connect to a switch that is
closed in all positions except OFF. Perhaps someone on the list
is familiar with that devices and possible sources.
I did a netsearch through my usual list of suspects (wicks, ACS,
airwolf) and couldn't find anything like it. Seems everyone is
offering the standard ACS-510 style aircraft switch (al-la Cessna).
How would you handle the second pump? You don't want both pumps
to share any more circuitry than necessary in order to have the
broadest redundancy.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Last questions for..... |
>
> >
> > Our aux battery management module CAN be used to automatically
> > close the aux battery master contactor even when the aux battery
> > master switch is OFF. This means that NORMAL flight ops call for
> > closing the aux battery master for engine cranking and then turning
> > it back OFF after the engine starts. Once the alternator brings the
> > bus to more than 13.0 volts, the aux battery is brought back on
> > line by the battery management module. The aux battery is
> > automatically
> > isolated if the alternator quits
>
>
>Most interesting : when is this beast to be offered on your website ?
It's available now if you gotta have it right away. I've
got the initial run of the critters built. I need to finish
the installation documentation (that also includes assembly
instructions for the kit version).
>Bob, thank you.
>Next time I'll make sure I avoid words like 'forgotten switch' or 'sp...t
>rocker switch'. Promise ;-)
We've all embarrassed ourselves and probably scared
the !@#$@# out of ourselves too on occasion. Good
human-engineering can minimize the probability (like
arranging logical rows of switches with normal operating
positions all UP - that's another plug for toggles . .
much more obvious than rockers). Combining the two
battery masters kills your ability to test them individually
in pre-flight.
Bob . . .
________________________________________________________________________________
| From: | "Darrell Anderson" <d.l.anderson(at)att.net> |
| Subject: | Whelen Strobe output switching |
I have a Whelen strobe power supply that has 4 outputs, (2 pair flashing
alternately). Is it possible to switch any individual output without
causing problems with longevity or safety? If so, which connection(s) would
be switched; Anode (425 volts!), ground, or trigger? My reason is that I
would like to connect a red anticollision strobe to the 4th output, and be
able to select it, or the 3 white wing/tail strobes, say, for taxi vs.
flight.
D. Anderson
________________________________________________________________________________
| Subject: | Re: Fuel pump question |
Bob,
Thank you once again.
> >
> >We wish to have the main pump run on the main hot battery bus any time
the
> >ignition switch is ON.
> >How can I wire the switch to achieve this goal ?
>
> There are no terminals on the contemporary OFF-L-R-BOTH-START
> magneto switches that would allow you to do this. I think there
> are some switches used on some ultra-lights that have a BAT (battery)
> and ACC (accessory) terminals that connect to a switch that is
> closed in all positions except OFF. Perhaps someone on the list
> is familiar with that devices and possible sources.
I'll try to investigate into the ultra light world.
>
> I did a netsearch through my usual list of suspects (wicks, ACS,
> airwolf) and couldn't find anything like it. Seems everyone is
> offering the standard ACS-510 style aircraft switch (al-la Cessna).
Too bad !
>
> How would you handle the second pump? You don't want both pumps
> to share any more circuitry than necessary in order to have the
> broadest redundancy.
>
Our intention is to run the second pump on the AUX always hot battery bus,
through a switch at the panel.
Cheers,
Gilles
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: Whelen Strobe output switching |
>
>
>I have a Whelen strobe power supply that has 4 outputs, (2 pair flashing
>alternately). Is it possible to switch any individual output without
>causing problems with longevity or safety? If so, which connection(s) would
>be switched; Anode (425 volts!), ground, or trigger? My reason is that I
>would like to connect a red anticollision strobe to the 4th output, and be
>able to select it, or the 3 white wing/tail strobes, say, for taxi vs.
>flight.
I think you could leave the trigger leads hooked to their
respective lamp fixtures and simply interrupt the hv lead
using a relay. A four-pole, double throw relay would do
the job to disconnect 3 and connect 1 when energized.
I don't think there's any hazard to the power supply
for doing this but it wouldn't hurt to talk to someone
a Whelen about it.
Bob . . .
________________________________________________________________________________
| From: | "Joe Larson" <jpl(at)showpage.org> |
| Subject: | thermocouple wires |
Okay, the rule is -- from the temp probe in our engine
or oil pan (or wherever you read oil temp from), we need
to use thermocouple wires all the way to the meter they
connect to. If we switch to copper, the system won' twork.
However, we can use a short splice of copper (ie: a d-connector)
as long as we have thermocouple wires on both sides to cancel
the copper connections.
If we don't do it this way, we'll get the temperature at the copper
connection instead of the temp probe.
Did I sum it up correctly?
Now, the big question: WHY? How does all this stuff work?
How does the temp probe actually pick up and transmit temperature,
how do the thermocouple wires transmit it, why doesn't copper work,
and what is the meter expecting to see?
If this is all in The Book or on The Website, I'm more than happy to
just go read.
-Joe
________________________________________________________________________________
| From: | Michel Therrien <mtherr(at)yahoo.com> |
| Subject: | Re: Whelen Strobe output switching |
My Whelen power supply has a connector for a switch
which would enable shutting off the wing strobes while
keeping a third one running.
=====
----------------------------
Michel Therrien CH601-HD
http://pages.infinit.net/mthobby
http://mthobby.pcperfect.com/ch601
http://taxes.yahoo.com/
________________________________________________________________________________
| From: | Michel Therrien <mtherr(at)yahoo.com> |
Is the Aeroelectric web site OK? I cannot access it
and I would like the article on making the battery
cable connectors.
=====
----------------------------
Michel Therrien CH601-HD
http://pages.infinit.net/mthobby
http://mthobby.pcperfect.com/ch601
http://taxes.yahoo.com/
________________________________________________________________________________
| From: | mprather(at)spro.net |
| Subject: | Re: thermocouple wires |
Have a look at:
http://www.rst-engr.com/rst/magazine/egtcht.pdf
It has a pretty good description of how all this works.
Matt Prather
----- Original Message -----
From: "Joe Larson" <jpl(at)showpage.org>
Date: Tuesday, April 16, 2002 8:14 am
Subject: AeroElectric-List: thermocouple wires
>
> Okay, the rule is -- from the temp probe in our engine
> or oil pan (or wherever you read oil temp from), we need
> to use thermocouple wires all the way to the meter they
> connect to. If we switch to copper, the system won' twork.
>
> However, we can use a short splice of copper (ie: a d-connector)
> as long as we have thermocouple wires on both sides to cancel
> the copper connections.
>
> If we don't do it this way, we'll get the temperature at the copper
> connection instead of the temp probe.
>
> Did I sum it up correctly?
>
> Now, the big question: WHY? How does all this stuff work?
> How does the temp probe actually pick up and transmit temperature,
> how do the thermocouple wires transmit it, why doesn't copper work,
> and what is the meter expecting to see?
>
> If this is all in The Book or on The Website, I'm more than happy to
> just go read.
>
> -Joe
>
>
> _-
>
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> _-
>
!! NEW !!
> _-
>
List Related Information
> _-
>
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>
>
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
>
>
>Is the Aeroelectric web site OK? I cannot access it
>and I would like the article on making the battery
>cable connectors.
Fixed now . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: thermocouple wires |
>
>Okay, the rule is -- from the temp probe in our engine
>or oil pan (or wherever you read oil temp from), we need
>to use thermocouple wires all the way to the meter they
>connect to. If we switch to copper, the system won' twork.
have you read the thermocouple section of the 'Connection?
You can download it at
http://209.134.106.21/articles/excerpt.pdf
>However, we can use a short splice of copper (ie: a d-connector)
>as long as we have thermocouple wires on both sides to cancel
>the copper connections.
>
>If we don't do it this way, we'll get the temperature at the copper
>connection instead of the temp probe.
>
>Did I sum it up correctly?
Nope.
>Now, the big question: WHY? How does all this stuff work?
>How does the temp probe actually pick up and transmit temperature,
>how do the thermocouple wires transmit it, why doesn't copper work,
>and what is the meter expecting to see?
>
>If this is all in The Book or on The Website, I'm more than happy to
>just go read.
ANY time you take two different metals and clamp them
together, the junction of the two metals will generate
a small but predictable voltage depending on the temperature
of the junction.
See http://www.ferrotec-america.com/3ref1.htm
To make use of this phenomenon, you must (1) account for
any and all other junctions of dissimilar materials including
extension wire, connectors, switches, etc. and (2) the
voltage generated at the junction of interest MUST be
compared with a junction of known temperature oft called
the "compensating", "cold" or "reference" junction.
ANY other junctions introduced into the system must
be introduced in pairs so that they cancel each other.
One example of this is shown in Figure 14-7 on how to
hose your thermocouples by improper use of switch.
Figure 14-10 speaks to the issue of "cold" junctions
and how they must be treated in order to get accurate
measurements should the cold junction be located remotely
from the measurement device.
At Cessna in the 60's we had a lot of thermocouple
installations wired like view-B in figure 14-10.
A thermos bottle fitted with a bored rubber stopper
contained a mixture of water and crushed ice. All
the thermocouples went into the ice bath and came
out on copper wire to the recording instruments.
Check over these suggested readings and then let's
revisit your project.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <nuckolls(at)kscable.com> |
| Subject: | Re: thermocouple wires |
>
>Have a look at:
>
>http://www.rst-engr.com/rst/magazine/egtcht.pdf
>
>It has a pretty good description of how all this works.
This is a good hammer-n-tongs piece on working
with thermocouples but it does not speak to the
need for a reference junction. It also speaks
about heating effects of galvanic corrosion with
some shaky science but by-in-large, the article
is factually useful.
Bob . . .
________________________________________________________________________________
| From: | "William Yamokoski" <yamokosk(at)lmc.cc.mi.us> |
| Subject: | KT-76C Installation Manual |
I've come across a KT-76C transponder, of course without manuals. Is there any
source for downloading the installation manual, or does Bendix/King keep pretty
tight reins on that sort of thing. I have a fairly indecipherable pin diagram
for making up a harness but......I need more! Any suggestions?
Bill Yamokoski
________________________________________________________________________________
| From: | mprather(at)spro.net |
| Subject: | Re: thermocouple wires |
As my previous comments might have shown, I am ALL about
hammer-n-tongs... :)
Mr Nuckolls, thanks for the links.
Matt Prather
> >
> >Have a look at:
> >
> >http://www.rst-engr.com/rst/magazine/egtcht.pdf
> >
> >It has a pretty good description of how all this works.
>
>
> This is a good hammer-n-tongs piece on working
> with thermocouples but it does not speak to the
> need for a reference junction. It also speaks
> about heating effects of galvanic corrosion with
> some shaky science but by-in-large, the article
> is factually useful.
>
> Bob . . .
>
>
> _-
>
________________________________________________________________________________
| From: | "Sanders, Andrew P" <andrew.p.sanders(at)boeing.com> |
| Subject: | RE: Capacitors in DC Circuit |
Matt:
Please let us know how electrical circuits are like plumbing.
Andrew
>>Don't get me going on how electrical circuits are like plumbing...
Matt Prather<<
________________________________________________________________________________
| From: | "Werner Schneider" <WernerSchneider(at)compuserve.com> |
| Subject: | Non PMA strobe and navigation lights, experience |
Dear Listers,
I've seen in the ASP catalog, that the Aeroflash Nav/Strobe kit is nearly
half the price of the Whelen.
Has anyone any experience about this equipment? Why not saving some bucks
for better things =(;o)
Many thanks for your feedback!
Werner
April 05, 2002 - April 16, 2002
AeroElectric-Archive.digest.vol-at