AeroElectric-Archive.digest.vol-bz
May 06, 2003 - May 13, 2003
________________________________________________________________________________
| From: | Mark Phillips <ripsteel(at)edge.net> |
| Subject: | Re: Galls Flasher circuit |
Here ya go- one's a .jpg and the other is a .tif (!) Suffice it to say
that Windows-X-FREAKIN'-P and I are NOT getting along-
grrrrrrrrrrrrrrrrrrrrrrr!!!!!!
..........but Explorer will open them both and they look fairly legible
on this end- any questions, let me know! By the way, they were done in
AutoCad R14, so if you have a CAD package, they would work much better &
you can edit to your hearts' content- If you want the .dwg files, let
me know- I did my entire "wirebook" this way- these are only 2 pages out
of WAY too many!!! 8-)
Note that the Landing light circuit is referenced on the right side of
the Taxi/flasher drawing- running both lights from the 2-10 would work
fine if you used the center postion for "both". The slick thing about
this way of doing it is if the relay fails, you still have both lights
and if either light fails, (or switch) you still have the other light
and possibly the flasher, and neither light is dependant on it. I
originally came up with this because I had the taxi light and flasher on
the main bus and the landing light on the e-bus so I'd have a light even
if the master contactor took a crap, or the main bus just failed for
some reason. After much consideration and several chidings from Bob N.,
I opted to keep the total possible e-bus loads to as small as practical
for a number of reasons. Therefore, they are both on the main, just
completely independant of each other except they are wired through the
relay.
Hope this helps.......
Mark
Joel Harding wrote:
>
> Mark,
> Yes I would be interested in the drawing. What I'm trying to
> accomplish is a setup that for me would be intuitive, with the 2-10
> switch giving me OFF, TAXI, AND TAXI PLUS LANDING LIGHT. Then I would
> like to turn the flasher on or off with a separate SP switch. If your
> configuration can accomplish that, then that's what I'm looking for. I
> can certainly identify with your comment about simple and
> straightforward. Thanks for the info.
>
> Joel Harding
>
>
> On Tuesday, May 6, 2003, at 12:20 PM, Mark Phillips wrote:
>
>
>>
>>
>>Joel- I'm using a 3PDT relay with three separate SPST switches that
>>provides the
>>capability or either or both lights on, and either or both lights
>>flashing.
>>(Galls FS020 flasher) Looks like you could do the same with the 2-10,
>>one other
>>SP switch and the relay. Not sure if this is what you are looking
>>for, but it's
>>fairly simple and straightforward (has to be for me to understand it
>>anyway!)
>>If interested I could send you a dwg.
>>
>>Here's the relay: ( $14.56)
>>http://www.mouser.com/ and search for: 528-3898-12
>>
>>Catalog page is: http://www.mouser.com//catalog//614/757.pdf
>>
>>It has .25" faston terminals and a mounting bracket built in to the
>>housing, so
>>no socket is required.
>>
>>From the PossumWorks
>>Mark
>>
>>Joel Harding wrote:
>>
>>
>>>
>>>
>>>Bob,
>>>Is there any way to start with both taxi and landing lights on a 2-10
>>>switch and add the Galls flasher on a separate switch, without adding
>>>a
>>>lot more complexity ? I looked at your diagrams but couldn't figure
>>>out if it would be possible.
>>>
>>>Joel Harding
>>>
>>>
>>
>>_-
>>======================================================================
>>_-
>>======================================================================
>>_-
>>======================================================================
>>_-
>>======================================================================
>>
>>
>>
>
>
>
>
>
>
>
>
________________________________________________________________________________
| From: | James Freeman <flyeyes(at)bellsouth.net> |
On Tuesday, May 6, 2003, at 04:59 PM, Scott Bilinski wrote:
> So I have a Falcon T & B. This probably means I will have radio noise.
> How
> do I fix this when the time comes? It would be much eaisier to
> "install"
> the fix now while the panel is out for the last time.
FWIW this gauge seems to be a frequent noise source, but not always. I
fly two airplanes with these instruments and have had -no- radio noise.
One is a Cessna 140 with a TKM/Michels comm radio and the other is our
AirCam with a UPSAT GX-60 mounted directly below the Chinese turn
coordinator.
You can see the AirCam Panel at:
http://homepage.mac.com/flyeyes/PhotoAlbum6.html
There are no filters on either installation and both are noise-free.
IIRC Electric Bob suggests trying it first before applying patches--it
may not be broke...
HTH
JFF
________________________________________________________________________________
| Subject: | Re: Landing/taxi light warm up |
Subject: Re: AeroElectric-List: Landing/taxi light warm up
>Looks very interesting.=A0 Where can it be purchased.
=A0=A0=A0 Car parts store . . . #4352=A0 It was only used
=A0=A0=A0 on a few years of GM vehicles . . . low volume
=A0=A0=A0 product so expect to pay about $20 per bulb. But
=A0=A0=A0 they are the right size, shape and technology. Should
=A0=A0=A0 last a VERY long time in your airplane.
=A0=A0=A0 Bob . . .
Bob, I looked for this Halogen headlight with the # H4352 at auto parts
stores, but they all show this light to be SINGLE filament hi beam primarily
for Camaros. Small in size at only 2" x 5 1/4" and priced at $29.95 each. So
to get 2 hi beam for landing and 2 low beam for taxi, the price for 4
headlights is $120. Low beam is part # H4351.
I did see a dual filament headlight but it was almost twice as large and with
different connectors. Any further suggestions??
~Dennis~
________________________________________________________________________________
| From: | "Sam Hoskins" <shoskins(at)Globaleyes.net> |
| Subject: | Fuseblock CAD drawings |
Yeah, I have all that. I was just looking for the fuseblocks themselves.
No big deal, if they don't already exist.
Sam
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Robert
L. Nuckolls, III
Subject: Re: AeroElectric-List: Fuseblock CAD drawings
>
>
>Bob, do you have a link to a CAD version of the fuseblocks? It would be
>nice for my wirebook. I looked on seminar.dwg and didn't see it there.
For a wirebook, the fuseblock symbol is simply the bus bar with
fuses as opposed to breakers. You can configure your bus with either
form of circuit protection as needed . . . All of the z-drawings
are available from the website in .dwg format and most have
the busses set up to depict fuseblocks.
. . . or am I misunderstanding your query?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | My camera on Ebay . . . |
I'm planning to do LOT more media presentations and publishing
best done with high quality digital photography. After 45+
years I'm getting clean out of the chemical photo business.
Thought I would miss it when I upgraded to a new Canon EOS
a couple of years ago and sold all my darkroom equipment.
I ran a few rolls of film that the local one-hour place
processed to negatives for me for $3.00 a roll. Used a scanner
to digitize the negatives. Really good results but pretty
clumsy and slow turnaround. Found that 90% of my photo needs
were covered with the Mavica . . . and if I move up a couple
more model steps in the Mavica series, the digital route
will cover 100% of my needs.
Soooo . . . if anyone is interested in a nearly new 35mm
camera, they're welcome to take a peek at:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2927709307
I'm planning on ordering a new Mavica CD1000 next week.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Fuseblock CAD drawings |
>
>
>Yeah, I have all that. I was just looking for the fuseblocks themselves.
>
>No big deal, if they don't already exist.
2D mechanical drawings? I think I did them a few years back
but don't recall using them. I'll dig around in the archives
and see what I can find. I know I have an isometric view of
a 20 slot fuseblock.
Bob . . .
________________________________________________________________________________
| From: | "rondefly" <rondefly(at)pacbell.net> |
| Subject: | Fuseblock CAD drawings |
Sam, Take a look at these fuse blocks.
http://www.cabelas.com/cabelas/en/templates/links/link.jhtml?id=0019040&type
=pod&rid=7510101020603
Ron
Ron Triano Quicker one Q-200, 90% Done with 90% to go
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Sam
Hoskins
Subject: RE: AeroElectric-List: Fuseblock CAD drawings
Yeah, I have all that. I was just looking for the fuseblocks themselves.
No big deal, if they don't already exist.
Sam
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Robert
L. Nuckolls, III
Subject: Re: AeroElectric-List: Fuseblock CAD drawings
>
>
>Bob, do you have a link to a CAD version of the fuseblocks? It would be
>nice for my wirebook. I looked on seminar.dwg and didn't see it there.
For a wirebook, the fuseblock symbol is simply the bus bar with
fuses as opposed to breakers. You can configure your bus with either
form of circuit protection as needed . . . All of the z-drawings
are available from the website in .dwg format and most have
the busses set up to depict fuseblocks.
. . . or am I misunderstanding your query?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Landing/taxi light warm up |
>
>Subject: Re: AeroElectric-List: Landing/taxi light warm up
>
> >Looks very interesting.=A0 Where can it be purchased.
>
>=A0=A0=A0 Car parts store . . . #4352=A0 It was only used
>=A0=A0=A0 on a few years of GM vehicles . . . low volume
>=A0=A0=A0 product so expect to pay about $20 per bulb. But
>=A0=A0=A0 they are the right size, shape and technology. Should
>=A0=A0=A0 last a VERY long time in your airplane.
>
>=A0=A0=A0 Bob . . .
>
>
>Bob, I looked for this Halogen headlight with the # H4352 at auto parts
>stores, but they all show this light to be SINGLE filament hi beam primarily
>for Camaros. Small in size at only 2" x 5 1/4" and priced at $29.95 each. So
>to get 2 hi beam for landing and 2 low beam for taxi, the price for 4
>headlights is $120. Low beam is part # H4351.
>
>I did see a dual filament headlight but it was almost twice as large and with
>different connectors. Any further suggestions??
Hmmm . . . pulled the 4352 out of my junkbox and sho' 'nuf, it's
a single filament lamp. Sorry 'bout that. I'm unaware of any other
automotive parts in that envelope. If you want to use this
package, you'll probably have to settle for single filament lamps
on each side . . .
Given that they ARE halogen bulbs, the life should be quite long
compared to the so-called aircraft landing lights.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>
>I am purchasing wire to wire the panel of my RV6A. Am I correct that 95%
>of the job can be done with 16 gage wire?
>CH
20AWG is the most universal wire size.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>Bob,
>My thoughts on the dual electronic ignition was to put one ignition on the
>battery bus and the other on the essential bus, if the wire from the
>battery contactor to the battery bus broke, I would still have an
>electronic ignition that would work. If both ignitions were put on the
>battery bus, would opening the essential bus alternate feed switch restore
>the battery bus?
E-bus alternate feed switch has nothing to do with the
battery bus. Battery bus is always hot irrespective of
the position of any switch.
>The alternator field c.b., in figure Z-11, what is the purpose of the
>fuselink when the wire has a 5a c.b. protecting it?
The 5A breaker is remotely located from the main bus.
There is a wire segment between the main bus and the
breaker that is not protected. Any protection we put there
needs to have a time constant much longer than the breaker
so that an ov trip doesn't open the upstream protection.
>With the dual alt/single battery design (figure Z-12,) should I connect
>the aux alt on/off switch to the same bolt as the master switch?
Yes, if you're using fuse blocks, you'll need to remote the
field breakers for both alternators and use fusible links
from the main bus feed bolt.
HOWEVER . . . Figure Z-12 is not recommended for new
design. Note that the main busses drive breakers. This
is recommended for adding a second alternator to an
existing system like on a Bonanza or C-210 . . . or
a homebuilt that's already configured with breakers
and 1960's architecture system. If you're starting
from scratch, you can do better.
>Finally, the essential bus is shown connecting to the main bus via a bolt,
>there is only one bolt on my 20 amp fuse block that I bought from B&C.
>Should I also connect this bus via the single bolt?
Yes, the bolt is long enough to stack multiple terminals
on it.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Starter Contactor |
>
>I have an automotive engine with a solenoid controlled starter. I
>currently do not have a starter contactor. What is the purpose of the
>contactor? To remove high amp from bus? Or? Just wondering if while I'm
>modifying the wiring for OV protection if I should add a starter contactor
>and contactor engaged warning light..
see http://www.aeroelectric.com/articles/strtctr.pdf
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Odyssey PC625 Question |
>
>Bob or anybody...
>
>I find myself the proud owner of 2 PC625's (It's a long story... :)) and I
>have coming shortly a Superior XP-IO360 engine. Is one of these at 625
>cranking amps sufficient for this engine or would I be better advised to go
>the two battery route and switch them in parallel for cranking? Of course
>this would add 13 lbs... Any and all opinions/facts are welcome.
Battery selection is mostly driven by CAPACITY requirements
to support your endurance bus and to have a low enough
internal impedance to deliver the very small dose of energy
required to get an engine going. You use typically less than
5% of a battery's capacity to get the engine going.
ONE PC625 is plenty of battery to crank and engine. There
a SMALLER batteries yet that are plenty to crank and engine.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>Bob,
>My RV7A will have a 200HP IO 360. I see that your recommended Engine
>switch has three positions, Prime - Boost - Off.
>
>I don't understand the difference between Prime and Boost?
>Walter
Boost only turns on pump only. Prime turns on both
pump and opens primer valve. You don't need a primer
valve on an injected engine.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: JJN Current Limiters |
>
>Bob,
>
>I have 2 current limiters, a T-Tron JJN-70 and JJN-80 that I acquired some
>time ago to protect the b-lead from the battery. Some time has passed and
>I can no longer find the articles explaining the sizing of these devices.
>
>I now have a 40 amp alternator and am wondering if either of these current
>limiters is sized properly to protect the 40 amp alternator? Or would
>these be better suited for a 60 amp alternator?
Either will work for the 40A, use the 80A device for a 60A alternator.
See http://www.aeroelectric.com/articles/anl/anlvsjjs.html
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: BundleDeratingFactor |
>
>I'm having fun calculating the wire temperture rise using the methods of
>AC43-13 but don't know how to employ Figure 11-5 on page 11-31. For the
>right wing, I'm planning one 14awg landing light, one 18awg position
>light, and one 3 conductor 18awg shielded strobe wire, all three to be
>laid loosely inside the 3/4" plastic conduit Van sells. But I know a
>bundle derating factor of three can't be right because the wires aren't
>bundled closely together, the shielded wire actually bundles three wires,
>and the conduit restricts air circulation pretty severely because it's
>about 10' long. Is there a way to estimate the effects of these different
>factors, obtain an 'effective' number of wires in the bundle, and use the
>published derating curves which I assume apply to individual wires tie
>wrapped closely together in free air?
The current values shown on my wire table are already derated
for bundle service. The wire sizes you've cited will be just
fine.
Bob . . .
________________________________________________________________________________
| From: | "Gary Casey" <glcasey(at)adelphia.net> |
| Subject: | starter transients |
Just as an anecdotal data point: I used to own a Cessna TR182 with a
24-volt system and King Silver Crown radios. Occasionally the radios would
"reset" when the gear motor cycled, losing their stored frequencies. This
would never happen when being turned off with the power switch. One could
assume that the voltage transient caused by the gear motor is similar but of
a lower amplitude than a starter motor. After checking for the integrity of
all the electrical system components I put a high-frequency scope on the
avionics buss and cycled the gear motor (with the engine off, assuming that
the alternator couldn't respond to rapid transients anyway. As Bob would
predict I found no voltage "spikes", but did find that the voltage dropped
from 24 to about 14 in a very few nanoseconds. My theory, one that wasn't
contradicted by King after a few tries on their part to fix the radios, was
that the rapid negative spike was entirely different from a power disconnect
in that the power lead was essentially being instantly shorted to ground.
Any filter caps in the power supply portion of the radio would therefore be
shorted, eliminating any chance for the microprocessors to shut down
gracefully. If the power line had a choke an opportunity for a resonance
could have been set up. Anyway, that's all I could figure out and the
problem wasn't fixed until we switched to Garmins. I could find no one else
with the same radio/airframe combination that had that problem. If I had a
sophisticated microprocessor-driven avionics system that's the only problem
I can imagine by leaving the avionics on while cranking the engine. The
code in the equipment might not be robust enough to handle a sudden
power-down during the start-up routine.
Gary Casey
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>Bob, I was wondering how you were making out analyzing the
>Eggenfellner/EXPbus design? I'm not flying yet but I have my
>electrical design almost done using your Z-11a as the backbone.
>
>Randy Gaugler
I have about a half dozen piles of drawings sent to me
wherein people are trying to shoe-horn the EXP-Bus into
one of the z-drawings. I must confess, I'm not enthusiastic
about this. The result of any recommendations I might
make will be a compromise to architectures carefully
considered operational features . . . I think I'm going
to pass on this and all future deliberations about how
to make the EXP-Bus work better.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Fergus Kyle" <VE3LVO(at)rac.ca> |
Bob,
Since I was the catalyst for this latest round of skirmishes on the
avionics bus, I want you to know how much I appreciate your advocacy
for the OBAM community. The energy and commitment you apply to
improving the state of the art in aviation electronics is awesome and
we all owe you a big debt of gratitude. Joel Harding
May I add my name to what I am sure is a growing list of those who wish they
had written the above?
Ferg, Europa A064
________________________________________________________________________________
| From: | "aronsond" <aronsond(at)pacbell.net> |
Listers:
I have a noisy Falcon T&B from Van's. Have the rest of you found that this
unit sounds like a bearing is bad. It is 10X louder than my Citabria's
unit. Is it design or should I return it.
Dave Aronson
RV4 N504rv
At airport and racing to fly this month.
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: starter transients |
>
>Just as an anecdotal data point: I used to own a Cessna TR182 with a
>24-volt system and King Silver Crown radios. Occasionally the radios would
>"reset" when the gear motor cycled, losing their stored frequencies. This
>would never happen when being turned off with the power switch. One could
>assume that the voltage transient caused by the gear motor is similar but of
>a lower amplitude than a starter motor. After checking for the integrity of
>all the electrical system components I put a high-frequency scope on the
>avionics buss and cycled the gear motor (with the engine off, assuming that
>the alternator couldn't respond to rapid transients anyway. As Bob would
>predict I found no voltage "spikes", but did find that the voltage dropped
>from 24 to about 14 in a very few nanoseconds. My theory, one that wasn't
>contradicted by King after a few tries on their part to fix the radios, was
>that the rapid negative spike was entirely different from a power disconnect
>in that the power lead was essentially being instantly shorted to ground.
>Any filter caps in the power supply portion of the radio would therefore be
>shorted, eliminating any chance for the microprocessors to shut down
>gracefully. If the power line had a choke an opportunity for a resonance
>could have been set up. Anyway, that's all I could figure out and the
>problem wasn't fixed until we switched to Garmins. I could find no one else
>with the same radio/airframe combination that had that problem. If I had a
>sophisticated microprocessor-driven avionics system that's the only problem
>I can imagine by leaving the avionics on while cranking the engine. The
>code in the equipment might not be robust enough to handle a sudden
>power-down during the start-up routine.
>
>Gary Casey
Good detective work. Yup, what you've discovered is a shortcoming
in the wording of the DO-160 requirements for this situation.
Consider the following:
DO-160D, paragraph 16.5.4.3
"a. Definition - Voltages may momentarily vary below nominal for
any duration up to seven seconds"
"b. Requirement - The equipment, when exposed to this condition
shall operate within the applicable equipment performance
standards when returned to normal operating voltage range."
"With the equipment operating at nominal rated voltage, decrease
the input DC voltage to 6v for seven seconds. With the equipment
still energized, adjust the input DC voltage to nominal rated
value and DETERMINE COMPLIANCE WITH APPLICABLE EQUIPMENT
PERFORMANCE STANDARDS"
Doing this test as described is pretty silly . . . wonder
where that 7 seconds number came from. I'll be it's a wash-
over from cranking turbine engines where single spool engines
can put a very long, high current load on a battery. Never
mind that there are NO 14v turbine powered aircraft and
never mind the obvious fact that power interruptions can
(1) have a RANGE of times from 0 to whatever value you want to
pick and (2) have a variation of rise/fall times. In fact,
the wording of the definition says "UP TO SEVEN SECONDS".
This phrase clearly suggests a range of 0 - 7 seconds. Another
loophole in this test requirement is the establishment of
APPLICABLE EQUIPMENT PERFORMANCE STANDARDS. The manufacturer
gets to influence these. There are legal variations
that could be written into their "standards" that would
mask this effect.
I have personally interpreted this paragraph of DO-160 to
mean that I should account for brown-out conditions with
a suite of possible amplitudes, durations and wave-shapes
to explore my product's ability to ignore or be relatively
unaffected by such events. This would embrace the stimulus
you observed in the measurements you cited above.
It's this poor wording of DO-160 that prompts many folk
to ask for avionics bus protection . . . not because
of potential hazard to their product due to spikes but
erratic behavior due to brownout. They do 16.5.4.3
exactly as stated and pronounce their product "qualified"
and then weasel-word their way around obvious shortcomings
in their design.
DO-160 is a powerful and useful document but was, after
all, crafted by a committee and then probably edited
by bureaucrats and stenographers. It's not without flaws.
I think I'll craft a letter to RTCA suggesting that
this paragraph be revised to be more meaningful
and representative of real life on the bus of an
airplane (or any other vehicle).
Bob . . .
________________________________________________________________________________
| From: | Robert Miller <rmiller3(at)earthlink.net> |
Dear Bob:
Planning to go with Eggenfellner Sub....
The functionality of the electrical design, and redundancy, are attractive.
But I wish the EXPbus itself could be eliminated, and still achieve this.
I thought, perhaps, in some earlier postings on this list, an electrical system
for that
installation might be developed that provided that redundancy and functionality
without the
EXPbus and perhaps with greater simplicity?
I wonder if you are working on such a design?
Thanks for all you've taught so many of us.
Robert Miller
"Robert L. Nuckolls, III" wrote:
>
> >
> >Bob, I was wondering how you were making out analyzing the
> >Eggenfellner/EXPbus design? I'm not flying yet but I have my
> >electrical design almost done using your Z-11a as the backbone.
> >
> >Randy Gaugler
>
> I have about a half dozen piles of drawings sent to me
> wherein people are trying to shoe-horn the EXP-Bus into
> one of the z-drawings. I must confess, I'm not enthusiastic
> about this. The result of any recommendations I might
> make will be a compromise to architectures carefully
> considered operational features . . . I think I'm going
> to pass on this and all future deliberations about how
> to make the EXP-Bus work better.
>
> Bob . . .
>
> --------------------------------------------
> ( Knowing about a thing is different than )
> ( understanding it. One can know a lot )
> ( and still understand nothing. )
> ( C.F. Kettering )
> --------------------------------------------
>
________________________________________________________________________________
The specs. for H4351 and H4352 headlights are:
Part no. volts watts rated life
H4351 12.8 65 w 320 hrs.
H4352 12.8 55 w 1000 hrs.
There was no spec. for candle power but other halogen headlights that draw 55
w. are rated at 24,000 to 30,000 cp, and 65 w. 28,000 to 40,000 cp.
Steve
Springfield Auto Parts Co., Inc.
________________________________________________________________________________
| From: | "Edward O'Connor" <EdwardOConnor(at)compuserve.com> |
| Subject: | Insulated Window Butt Connectors |
I purchased some Butt connectors at Sun n Fun (Clear) for small wires
AWA 20-24. Since then I have been trying to find a squeezer die or
crimper for them at a reasonable price. They are shown in the new
Wicks Catalog Page 135 with a part # B1841BN. Wicks also lists a low
cost crimper down to #22 but not for #24. It might work but has anyone
used it before? The red position on the Pro Crimper I have will not
squeeze them tight. Thanks
Ed O'Connor/RV-8/Instruments/Sandy Creek Airpark/Panama City Fl
________________________________________________________________________________
| From: | "DAVID REEL" <dreel(at)cox.net> |
If anyone out there thinks radio noise from a turn & bank indicator is going to
be a problem, just wait until you have to try flying partial panel in an emergency.
The Dynon EFIS provides a real backup considering that my own, and I would
guess most people's, partial panel skills are lethally rusty. Yes it's 2
grand and not IFR certified, but it's just the ticket for emergency backup in
a VFR panel. I'd toss the turn and bank.
Dave Reel - RV8A
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
| Subject: | My camera on Ebay . . . |
Bob, can I make a recommendation? I would highly suggest you look at
the Cybershot cameras from Sony instead of the CD1000 you are looking
at. First off, I don't even think the CD1000 is produced anymore, which
means it is already out of date. I think the CD500 is the latest model
in the CD series. However, I think you'll find the CD and FD series
very large and cumbersome. I used to own both, first the FD-91 (top of
the line floppy disk one, 1Mp) and then the CD1000 (2Mp). They are just
so big and bulky, and they really don't have the specs of the new
cameras that cost the same. Now I have the Cybershot 707 which is 5Mp
and uses Memorysticks. I highly highly recommend this camera. I love
it. The things it will do will amaze you.
The new 717 has just been released (it supports the memory stick PRO,
which holds 1Gb), and the price has dropped to 799. I'm sure you can
find lots of 707 at decent prices now. I'd even sell mine to upgrade to
the new model that takes the 1Gb memory stick.
Just something to think about. I highly recommend the 707 or 717
(unless you are getting a killer deal on the cd1000)
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Robert L. Nuckolls, III
Subject: AeroElectric-List: My camera on Ebay . . .
I'm planning to do LOT more media presentations and publishing
best done with high quality digital photography. After 45+
years I'm getting clean out of the chemical photo business.
Thought I would miss it when I upgraded to a new Canon EOS
a couple of years ago and sold all my darkroom equipment.
I ran a few rolls of film that the local one-hour place
processed to negatives for me for $3.00 a roll. Used a scanner
to digitize the negatives. Really good results but pretty
clumsy and slow turnaround. Found that 90% of my photo needs
were covered with the Mavica . . . and if I move up a couple
more model steps in the Mavica series, the digital route
will cover 100% of my needs.
Soooo . . . if anyone is interested in a nearly new 35mm
camera, they're welcome to take a peek at:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2927709307
I'm planning on ordering a new Mavica CD1000 next week.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | Peter Laurence <dr.laurence(at)mbdi.org> |
Bob,
I'm a little puzzeled by this string:
> HOWEVER . . . Figure Z-12 is not recommended for new
> design. Note that the main busses drive breakers. This
> is recommended for adding a second alternator to an
> existing system like on a Bonanza or C-210 . . . or
> a homebuilt that's already configured with breakers
> and 1960's architecture system. If you're starting
> from scratch, you can do better.
>
> Bob . . .
>
>
> Figure Z-12 is the schematic you suggested for the Velocity XL ( starting
from scratch) utilizing a single battery ,60A and the B&C 20A alt.
How could I have done better?
Peter
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>Bob,
>
>I'm a little puzzeled by this string:
>
> > HOWEVER . . . Figure Z-12 is not recommended for new
> > design. Note that the main busses drive breakers. This
> > is recommended for adding a second alternator to an
> > existing system like on a Bonanza or C-210 . . . or
> > a homebuilt that's already configured with breakers
> > and 1960's architecture system. If you're starting
> > from scratch, you can do better.
> >
> > Bob . . .
> >
> >
> > Figure Z-12 is the schematic you suggested for the Velocity XL ( starting
>from scratch) utilizing a single battery ,60A and the B&C 20A alt.
>How could I have done better?
Figure Z-14 is better. If you have two alternators, either one
of which depends on a battery to keep running, then having a
single battery puts the whole system at risk for loss of
connection to the battery. An aux alternator diving the
main bus of a one battery system is the obvious upgrade to
the carved-in-stone system on a certified ship. Now, if you
have Figure Z-12 installed, you are head and shoulders above
most single engine certified ships flying for overall system
reliability. There are probably several hundred Bonanza
and C-210 pilots breathing a lot easier now that there is
a reliable replacement for the piece-of-!#$@# stand-by
generator that they just took off their airplane. So they
too have enjoyed a quantum jump in system reliability
for having the second alternator. Soooo . . . if the
AeroElectric Connection had never come along and you
had wired your Velocity like a C-172, you probably wouldn't
be worried in the least . . . or at least no worse than
if you were flying around in a stock Cessna. Now that
you have two alternators, you've got the best that RAC,
Piper or Mooney can offer in their finest S.E. offerings.
Bottom line is, if you have Z-12 up and running, I'd leave
it alone. It's a fine system. If we had some conversation
about it and you went went with Z-12 in lieu of Z-14
there must have been some consideration of weight of
two batteries or some issue with additional complexity.
Z-12 is VERY user friendly . . . it autoswitches and
annunciates a shift to standby alternator operations
if the main alternator fails. Lots of folks including
the FAA really like that feature.
None the less, if one seeks the very best we know how
to do today, Z-14 with consideration of spreading
critical items over two TOTALLY INDEPENDENT busses is the
way to do it. I know of NO CERTIFIED GA aircraft that
can match this reliability for independent generation and
distribution of power to flight critical systems . . .
$million$ bizjets go though all kinds of monkey-motion
to achieve the system reliability that is probably not
as good as Figure Z-14.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | My camera on Ebay . . . |
>
>
>Bob, can I make a recommendation? I would highly suggest you look at
>the Cybershot cameras from Sony instead of the CD1000 you are looking
>at. First off, I don't even think the CD1000 is produced anymore, which
>means it is already out of date. I think the CD500 is the latest model
>in the CD series. However, I think you'll find the CD and FD series
>very large and cumbersome. I used to own both, first the FD-91 (top of
>the line floppy disk one, 1Mp) and then the CD1000 (2Mp). They are just
>so big and bulky, and they really don't have the specs of the new
>cameras that cost the same. Now I have the Cybershot 707 which is 5Mp
>and uses Memorysticks. I highly highly recommend this camera. I love
>it. The things it will do will amaze you.
>
>The new 717 has just been released (it supports the memory stick PRO,
>which holds 1Gb), and the price has dropped to 799. I'm sure you can
>find lots of 707 at decent prices now. I'd even sell mine to upgrade to
>the new model that takes the 1Gb memory stick.
>
>Just something to think about. I highly recommend the 707 or 717
>(unless you are getting a killer deal on the cd1000)
I've looked at the stick memory cameras and will eventually
go that route. I usually buy upgrades at the tail end of
market on a product. You get a lot more for your money that
way.
I got spoiled with the 14x optical zoom on the current
digital camera (FD91). I may keep it out at RAC . . . we have
digital cameras all over the place guarded by folks who
are not always easy to find. I'd rather supply my own
camera. The 1000 is older than the 500 but at least has
a 10x optical zoom. It's CD writing system is not as
handy as the floppy for handing images to folks in real
time which is another reason I'll keep the FD91 around.
Size isn't really a big issue for me. I've got a nearly
antique Olympus XA2 for pocket-sized snap shots. When I've
got business photos to do, a whole new criteria kicks
in. May end up with something different but for now,
there are several CD1000's on ebay I'm tracking. I
appreciate your input!
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>
>Dear Bob:
>
>Planning to go with Eggenfellner Sub....
>The functionality of the electrical design, and redundancy, are attractive.
>But I wish the EXPbus itself could be eliminated, and still achieve this.
>
>I thought, perhaps, in some earlier postings on this list, an electrical
>system for that
>installation might be developed that provided that redundancy and
>functionality without the
>EXPbus and perhaps with greater simplicity?
>I wonder if you are working on such a design?
>
>Thanks for all you've taught so many of us.
>
>Robert Miller
What does the Exp-Bus do for you that one of the
Z-figures does not?
Bob . . .
________________________________________________________________________________
| From: | Robert Miller <rmiller3(at)earthlink.net> |
"Robert L. Nuckolls, III" wrote:
> What does the Exp-Bus do for you that one of the
> Z-figures does not?
>
> Bob . . .
>
Yes... that's it exactly.
I do wish to eliminate the EXPbus (just can't make myself comfortable with using
it)
The functionality of the electrical system hammered out for the E-Sub installation
guide
provides:
1. Redundant supply, using two batteries ... for an engine that must have electrical
supply
to run - including for processing unit
2. Automatic switching-in of back-up fuel pump, if fuel pressure were to fall,
using
"fail-over relay"... pilot would only know this has happened because of annunciatior.
3. An "essential Bus"
I agree that the Z designs are able to provide much of this, and probably be more
robust in
the process. I guess what I am asking is for someone (more knowledgeable than
I) to sketch
out the equivalent of the electrical guide for the E-Sub as beautifully done by
Gary, except
not using the EXPbus.
Robert
>
> >
> >
> >Dear Bob:
> >
> >Planning to go with Eggenfellner Sub....
> >The functionality of the electrical design, and redundancy, are attractive.
> >But I wish the EXPbus itself could be eliminated, and still achieve this.
> >
> >I thought, perhaps, in some earlier postings on this list, an electrical
> >system for that
> >installation might be developed that provided that redundancy and
> >functionality without the
> >EXPbus and perhaps with greater simplicity?
> >I wonder if you are working on such a design?
> >
> >Thanks for all you've taught so many of us.
> >
> >Robert Miller
>
> What does the Exp-Bus do for you that one of the
> Z-figures does not?
>
> Bob . . .
________________________________________________________________________________
| From: | Ralph <rdf1del1(at)yahoo.com> |
If I can pipe in on this thread, all the features that you have described are easily
accomplish using the Z designs with the addition of a low fuel pressure
switch attached to a fuel pump relay, this will give you the switch over feature
you were asking about. What the expbus will not do is give you flexability
in the future to add or subtract systems as your aircraft evolves. We live in
an era of rapid change therefore flexability is vital. Ralph
Robert Miller wrote:--> AeroElectric-List message posted
by: Robert Miller
"Robert L. Nuckolls, III" wrote:
> What does the Exp-Bus do for you that one of the
> Z-figures does not?
>
> Bob . . .
>
Yes... that's it exactly.
I do wish to eliminate the EXPbus (just can't make myself comfortable with using
it)
The functionality of the electrical system hammered out for the E-Sub installation
guide
provides:
1. Redundant supply, using two batteries ... for an engine that must have electrical
supply
to run - including for processing unit
2. Automatic switching-in of back-up fuel pump, if fuel pressure were to fall,
using
"fail-over relay"... pilot would only know this has happened because of annunciatior.
3. An "essential Bus"
I agree that the Z designs are able to provide much of this, and probably be more
robust in
the process. I guess what I am asking is for someone (more knowledgeable than I)
to sketch
out the equivalent of the electrical guide for the E-Sub as beautifully done by
Gary, except
not using the EXPbus.
Robert
>
> >
> >
> >Dear Bob:
> >
> >Planning to go with Eggenfellner Sub....
> >The functionality of the electrical design, and redundancy, are attractive.
> >But I wish the EXPbus itself could be eliminated, and still achieve this.
> >
> >I thought, perhaps, in some earlier postings on this list, an electrical
> >system for that
> >installation might be developed that provided that redundancy and
> >functionality without the
> >EXPbus and perhaps with greater simplicity?
> >I wonder if you are working on such a design?
> >
> >Thanks for all you've taught so many of us.
> >
> >Robert Miller
>
> What does the Exp-Bus do for you that one of the
> Z-figures does not?
>
> Bob . . .
---------------------------------
________________________________________________________________________________
| From: | "Steve J Hurlbut" <sjhdcl(at)kingston.net> |
Can someone point me in the right direction to learn more about "Z designs"?
Steve
Rv7A
Eggenfellner Subaru
Exp Bus
Wiring all done
----- Original Message -----
From: "Robert Miller" <rmiller3(at)earthlink.net>
Subject: Re: AeroElectric-List: EXPbus
>
> "Robert L. Nuckolls, III" wrote:
>
>
> > What does the Exp-Bus do for you that one of the
> > Z-figures does not?
> >
> > Bob . . .
> >
>
> Yes... that's it exactly.
> I do wish to eliminate the EXPbus (just can't make myself comfortable
with using it)
>
> The functionality of the electrical system hammered out for the E-Sub
installation guide
> provides:
> 1. Redundant supply, using two batteries ... for an engine that must have
electrical supply
> to run - including for processing unit
> 2. Automatic switching-in of back-up fuel pump, if fuel pressure were to
fall, using
> "fail-over relay"... pilot would only know this has happened because of
annunciatior.
> 3. An "essential Bus"
>
> I agree that the Z designs are able to provide much of this, and probably
be more robust in
> the process. I guess what I am asking is for someone (more knowledgeable
than I) to sketch
> out the equivalent of the electrical guide for the E-Sub as beautifully
done by Gary, except
> not using the EXPbus.
>
> Robert
>
> >
> > >
> > >
> > >Dear Bob:
> > >
> > >Planning to go with Eggenfellner Sub....
> > >The functionality of the electrical design, and redundancy, are
attractive.
> > >But I wish the EXPbus itself could be eliminated, and still achieve
this.
> > >
> > >I thought, perhaps, in some earlier postings on this list, an
electrical
> > >system for that
> > >installation might be developed that provided that redundancy and
> > >functionality without the
> > >EXPbus and perhaps with greater simplicity?
> > >I wonder if you are working on such a design?
> > >
> > >Thanks for all you've taught so many of us.
> > >
> > >Robert Miller
> >
> > What does the Exp-Bus do for you that one of the
> > Z-figures does not?
> >
> > Bob . . .
>
>
________________________________________________________________________________
| From: | "Sam Hoskins" <shoskins(at)Globaleyes.net> |
Allow me...
Buy bob's book, the AeroElectric connection. Best $35 you will ever spend.
It has all the Zzzzzs, and much much more.
http://www.aeroelectric.com/Catalog/AECcatalog.html
Sam
Jusst completing re-wiring my Quickie Q-200
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Steve
J Hurlbut
Subject: Re: AeroElectric-List: EXPbus
Can someone point me in the right direction to learn more about "Z designs"?
Steve
Rv7A
Eggenfellner Subaru
Exp Bus
Wiring all done
----- Original Message -----
From: "Robert Miller" <rmiller3(at)earthlink.net>
Subject: Re: AeroElectric-List: EXPbus
>
> "Robert L. Nuckolls, III" wrote:
>
>
> > What does the Exp-Bus do for you that one of the
> > Z-figures does not?
> >
> > Bob . . .
> >
>
> Yes... that's it exactly.
> I do wish to eliminate the EXPbus (just can't make myself comfortable
with using it)
>
> The functionality of the electrical system hammered out for the E-Sub
installation guide
> provides:
> 1. Redundant supply, using two batteries ... for an engine that must have
electrical supply
> to run - including for processing unit
> 2. Automatic switching-in of back-up fuel pump, if fuel pressure were to
fall, using
> "fail-over relay"... pilot would only know this has happened because of
annunciatior.
> 3. An "essential Bus"
>
> I agree that the Z designs are able to provide much of this, and probably
be more robust in
> the process. I guess what I am asking is for someone (more knowledgeable
than I) to sketch
> out the equivalent of the electrical guide for the E-Sub as beautifully
done by Gary, except
> not using the EXPbus.
>
> Robert
>
> >
> > >
> > >
> > >Dear Bob:
> > >
> > >Planning to go with Eggenfellner Sub....
> > >The functionality of the electrical design, and redundancy, are
attractive.
> > >But I wish the EXPbus itself could be eliminated, and still achieve
this.
> > >
> > >I thought, perhaps, in some earlier postings on this list, an
electrical
> > >system for that
> > >installation might be developed that provided that redundancy and
> > >functionality without the
> > >EXPbus and perhaps with greater simplicity?
> > >I wonder if you are working on such a design?
> > >
> > >Thanks for all you've taught so many of us.
> > >
> > >Robert Miller
> >
> > What does the Exp-Bus do for you that one of the
> > Z-figures does not?
> >
> > Bob . . .
>
>
________________________________________________________________________________
| From: | Kevin Horton <khorto1537(at)rogers.com> |
Steve,
The downloadable materials section on Bob Nuckolls' web site is a
good place to start.
http://www.aeroelectric.com/articles.html
His drawings are in Appendix Z to the Aeroelectric Connection that he
sells. Appendix Z can be downloaded at:
http://www.aeroelectric.com/articles/Rev10/z10.pdf
Also read:
http://www.aeroelectric.com/articles/allelect.pdf
http://www.aeroelectric.com/articles/All_Electric/allelect.html
http://www.aeroelectric.com/articles/failtoll.pdf
http://www.aeroelectric.com/articles/expbusad.html
http://www.aeroelectric.com/articles/Carling_Micro/Carling_Micro.pdf
The Aeroelectric Connection is described at:
http://www.aeroelectric.com/Catalog/pub/pub.html
It is a very worthwhile purchase, but it does take some time and
effort to read and digest it.
Kevin
>
>
>Can someone point me in the right direction to learn more about "Z designs"?
>
>Steve
>Rv7A
>Eggenfellner Subaru
>Exp Bus
>Wiring all done
>
>----- Original Message -----
>From: "Robert Miller" <rmiller3(at)earthlink.net>
>To:
>Subject: Re: AeroElectric-List: EXPbus
>
>
>
>>
>> "Robert L. Nuckolls, III" wrote:
>>
>>
>> > What does the Exp-Bus do for you that one of the
>> > Z-figures does not?
>> >
>> > Bob . . .
>> >
>>
>> Yes... that's it exactly.
>> I do wish to eliminate the EXPbus (just can't make myself comfortable
>with using it)
>>
>> The functionality of the electrical system hammered out for the E-Sub
>installation guide
>> provides:
>> 1. Redundant supply, using two batteries ... for an engine that must have
>electrical supply
>> to run - including for processing unit
>> 2. Automatic switching-in of back-up fuel pump, if fuel pressure were to
>fall, using
>> "fail-over relay"... pilot would only know this has happened because of
>annunciatior.
>> 3. An "essential Bus"
>>
>> I agree that the Z designs are able to provide much of this, and probably
>be more robust in
>> the process. I guess what I am asking is for someone (more knowledgeable
>than I) to sketch
>> out the equivalent of the electrical guide for the E-Sub as beautifully
>done by Gary, except
>> not using the EXPbus.
>>
>> Robert
>>
>
>> >
>> > >
>> > >
>> > >Dear Bob:
>> > >
>> > >Planning to go with Eggenfellner Sub....
>> > >The functionality of the electrical design, and redundancy, are
>attractive.
>> > >But I wish the EXPbus itself could be eliminated, and still achieve
>this.
>> > >
>> > >I thought, perhaps, in some earlier postings on this list, an
>electrical
>> > >system for that
>> > >installation might be developed that provided that redundancy and
>> > >functionality without the
>> > >EXPbus and perhaps with greater simplicity?
>> > >I wonder if you are working on such a design?
>> > >
>> > >Thanks for all you've taught so many of us.
>> > >
>> > >Robert Miller
>> >
>> > What does the Exp-Bus do for you that one of the
>> > Z-figures does not?
>> >
>> > Bob . . .
>>
>>
>
>
________________________________________________________________________________
| From: | "David Carter" <dcarter(at)datarecall.net> |
"RV-list" ,
"aeroelectric-list"
| Subject: | Builder documentation on the Web-summary |
I received 13 excellent, helpful replies to my request for "how to create drawings,
sketches, & tables viewable on a web site". Thank you all.
Here's a summary of what I learned:
1. Drawings made by CAD programs (Autocad, Intellicad-an Autocad "full features
clone" (I have Airplane PDQ which has full Intellicad embedded):
a. File, Export to File, in the Save As box navigate to the desired folder,
use or change the file name, then go to File Type & scroll down to & select .bmp;
that all disappears and you are back in Intellicad with the "Selection Menu"
box popped up - click "select all" then press "Enter" (a non-intuitive response
to a command line question) and in a short moment the conversion is completed.
b. Then use Paint (MSPAINT) to open the file & immediately Save As a .jpg
Everyone with Windows has Microsoft's "Paint" for this .bmp to .jpg conversion.
And everyone with Windows has Kodak's "Imaging" program that views
.jpgs, plus .jpg files/images are imbedded directly into aweb page and thus viewable
by a browser.
(interesting side note: My "Imaging" pgm won't let me save anything as .jpg
. . . weird.)
2. Non-cad drawings and sketches (fuel system, simple electrical schematics or
wire diagrams, etc)
a. Hand draw and color sketches and simply scan them as .jpg files to insert
into web page; or,
b. Use "Paint" (MSPAINT.EXE in Programs, Accessories) for Sketches -
c. Excel has a "drawing" mode with lots of features.
- Another lister several months ago shared how he used Excel to "draw"
a very neat electrical schematic.
- My impression is that one would be able to "draw" a neater, more detailed
drawing than using PAINT - maybe easier, too, since Exel has more drawing
features than the rudimentary lines, rectangle, and "free hand with a mouse"
of PAINT.
3. Lists/tables created in Excel:
"File", "Save as" and select .html as file type; or "File", "Save as Web Page"
and navigate through the pop-ups.
- This isn't a .jpg but it works - displayed nicely.
-- However, if I want to control how it displays, I think I'd have
to spend extra time to gain a lot more knowledge of HTML than I currently have
- When I viewed this file in my browser and clicked View, Source, it was a
long complex document, not like a single line entry for an anchor tag to reference
a single .jpg image.
- - - - - - - - - - - - -
Bill Shertz suggested exporting files as .gif. I tried that on an Intellicad drawing
and it displayed as a black rectangle, without the colored lines of the
drawing. I can't say more about use of .gif. What programs will display it?
Other tips (summary listing):
1. Eric M. Jones: If you have an interest in CAD, please see http://www.tenlinks.com/CAD/products/free/cad.htm. This is a repository of all things in free cad, and add-ons too
2. Chris Good: Powerpoint has an "export to html" function that creates the pages
on the web site.
3. Ernest Christley: Try "The Gimp". There is a version for Windo[ws]
It's a Photoshop wannabe, that will cost you exactly $0. You'll be able to work
on the JPG files and do lots of other neat things if you'll just spend a few
hours with the included documentation. As a bonus, the JPG files it produces
tend to be about 1/4th the size of what my digital camera program produces.
4. Dale Smith: "jpeg optimizer" will trim your photos' file size literally to any size you like, all the while showing you in a window what the downsized picture file looks like! ... it's shareware located for download on CNet at: http://download.com.com/3000-2192-9623164.html
- File sizes a third of the original show with almost negligible differences.
If it does degrade, just kick it up a few percent. You don't need to re-size
most pics down to enjoy the benefits, but cropping out the unneeded always
helps keep the filesize in check.
5. Rob Housman: Use "FinePrint" to save the file in Adobe Acrobat's pdf format. Go to www.fineprint.com and download the free version of that program. [ This sounds like one to get familiar with. ]
6. Dan Checkoway: There are plenty of forums and self-teach web sites out there for web development. See http://www.w3schools.com, for example. [ I went to this and will use it as my primary learning tool for web stuff.]
7. Joshua Siler: Adobe Photoshop and Illustrator, with a tablet input device,
are the
best ways to do this [sketches]. However they are quite expensive.
- Try Paint Shop Pro 8.0 - you can find it at http://www.download.com . It will let you create an
image, and then you can save it as a file format that windows can read.
David Carter
RV-6 (into first wiring - to tail lights; started my "Electrical System Loads by
Phase of Flight" spreadsheet; needing to sketch 13B rotary engine cooling system
design variations for peer review) (learning to document my work and "systems"
somewhere besides my "Word Perfect" word processor for DOS)
________________________________________________________________________________
| From: | "Rick Fogerson" <rickf(at)cableone.net> |
| Subject: | Microair Radio-Xpdr Wire Harness |
Hi Bob,
Are you going to be selling wiring harness's for the Microair radio or xpdr anytime
soon? Also, the xpdr itself?
Rick Fogerson
________________________________________________________________________________
| From: | "William Bernard" <billbernard(at)worldnet.att.net> |
| Subject: | Source for Brass Bolt |
I'm trying to follow Bob's recommendation to use a 5/16" (or bigger)brass bolt
to get the ground wire through the firewall. I need to get the wire up from the
bottom of the aircraft around a large fuel tank mounted near the firewall, up
to the top where the ground buss is located.
Does anyone have a source for a 5/16" bolt? The biggest I've been able to locate
so far is 1/4".
Thanks for the help.
Bill
________________________________________________________________________________
| From: | "David Swartzendruber" <dswartzendruber(at)earthlink.net> |
| Subject: | Source for Brass Bolt |
McMaster-Carr at www.mcmaster.com has them. P/N for a 2" bolt is
92941A591 and costs $5.97 for ten. B&C might sell you a bolt also.
Dave in Wichita
>
> Does anyone have a source for a 5/16" bolt? The biggest I've been able
to
> locate so far is 1/4".
>
> Bill
________________________________________________________________________________
| Subject: | Re: Source for Brass Bolt |
McMaster-Carr, 5/16-18 X 1
Do a search on McMaster-Carr
P/N 92941A583
>
>
>I'm trying to follow Bob's recommendation to use a 5/16" (or bigger)brass
>bolt to get the ground wire through the firewall. I need to get the wire up
>from the bottom of the aircraft around a large fuel tank mounted near the
>firewall, up to the top where the ground buss is located.
>
>Does anyone have a source for a 5/16" bolt? The biggest I've been able to
>locate so far is 1/4".
>
>Thanks for the help.
>
>Bill
>
>
Scott Bilinski
Eng dept 305
Phone (858) 657-2536
Pager (858) 502-5190
________________________________________________________________________________
| From: | "Cy Galley" <cgalley(at)qcbc.org> |
| Subject: | Re: Source for Brass Bolt |
Plumbing Supply?
----- Original Message -----
From: "William Bernard" <billbernard(at)worldnet.att.net>
Subject: AeroElectric-List: Source for Brass Bolt
>
> I'm trying to follow Bob's recommendation to use a 5/16" (or bigger)brass
bolt to get the ground wire through the firewall. I need to get the wire up
from the bottom of the aircraft around a large fuel tank mounted near the
firewall, up to the top where the ground buss is located.
>
> Does anyone have a source for a 5/16" bolt? The biggest I've been able to
locate so far is 1/4".
>
> Thanks for the help.
>
> Bill
>
>
________________________________________________________________________________
| From: | "Don Honabach" <don(at)pcperfect.com> |
My panel is just going to be VFR, but I decided to go with the Dynon
unit as well and received mine just last week. Extremely nice all in one
unit and since I'm VFR only, the instrument count and panel complexity
(both in front and in back) has just decreased dramatically.
For what it's worth, they also have options for an internal battery
backup and an external battery backup. So it would be very easy to have
the instrument stay alive during an electric failure.
Only issue so far is that the magnetic heading seems to jump around, but
I haven't had a chance to do their calibration procedure yet and I'm
still waiting on my external compass box which should also help.
My only real complaint is that I don't have enough free time to try and
design one myself. According to the folks at Dynon it's based 4 Cypress
uControllers linked to solid-state gyros. I can't wait until someone
comes out with a solid-state gyro package with a USB or similar
interface - just jury rig a PC and screen and you've got your on
customized EFIS unit.
Regards,
Don
-----Original Message-----
From: DAVID REEL [mailto:dreel(at)cox.net]
Subject: Re: AeroElectric-List: falcon t
If anyone out there thinks radio noise from a turn & bank indicator is
going to be a problem, just wait until you have to try flying partial
panel in an emergency. The Dynon EFIS provides a real backup
considering that my own, and I would guess most people's, partial panel
skills are lethally rusty. Yes it's 2 grand and not IFR certified, but
it's just the ticket for emergency backup in a VFR panel. I'd toss the
turn and bank.
Dave Reel - RV8A
direct advertising on the Matronics Forums.
________________________________________________________________________________
| From: | "Muzzy Norman E" <MuzzyNormanE(at)JohnDeere.com> |
| Subject: | Z-13 and Dual Electronic Ignitions |
I will run with a 40A alternator and an SD-8 for engine driven power
sources, and a pair of electronic ignition systems (no mags). The Z-13
diagram lays out the architecture for the SD-8 and L40 charging system with
one battery. I could wire my ignition systems directly to the Battery bus
as shown. It has been said several times that an electrically dependent
ignition design really deserves two batteries. So, where do we go to
achieve this?
We could adopt the architecture of Z-14 but use the SD-8 as a second
alternator. One of the challenges with this architecture is that it
requires a minimum of two contactors to power the busses where the essential
items reside. The ignition systems would be located one each on the battery
busses. I think that Z-14 makes sense with two big alternators, but may not
be optimized for the SD-8.
Or, we could add an additional battery to Z-13 using Figure Z-30. In this
manner, we can run the essential bus philosophy, with an additional battery
that could be isolated from the rest of the charging system. In order to
supply the essential bus from the second battery, we need to modify how the
essential bus is powered. As soon as you do that, it begins to smell a lot
like an avionics bus, which can be powered from either Battery 1 or Battery
2. We can: A) leave it as is, with the diode to one of the main busses and
alt feed from the same battery. B) use a 3 position switch as a selector
between the two batteries (There's that avionics bus smell again...),
eliminate the diode (to prevent tying the batteries together during starting
if the alt feed switch were on, or if one of the battery busses were somehow
pulled close to ground).
While we are considering how to tie this second battery in, we are also
being reminded that using lightweight washers instead of standard washers
could save a few ounces on your airframe. And that adding weight is even
worse than installing a split master switch! So, that little voice in the
back of our head encourages us to install the Z-13 system with a single
battery and save the weight.
My gut tells me to add a second battery to the Z-13 architecture, using the
Z-30 technique. Tie the E-bus to the Battery bus that is associated with
the SD-8.
I suspect that I am not alone in debating these possibilities, and would
like to here some discussion on what would be the appropriate manner to
handle feeding the E-bus.
Regards-
Norm
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Source for Brass Bolt |
I've purchased them at the specialty hardware sections of Home Depot,
Lowes, etc. Floor flange bolts for a commode are 5/16 brass but
coarse thread. If push comes to shove, B&C can fix you up. They
stock several lengths along with brass washers, phosphor bronze
lockwashers, and brass nuts to go with them.
Bob . . .
> >
> > I'm trying to follow Bob's recommendation to use a 5/16" (or bigger)brass
>bolt to get the ground wire through the firewall. I need to get the wire up
>from the bottom of the aircraft around a large fuel tank mounted near the
>firewall, up to the top where the ground buss is located.
> >
> > Does anyone have a source for a 5/16" bolt? The biggest I've been able to
>locate so far is 1/4".
> >
________________________________________________________________________________
| Subject: | Whelen strobe current draw and grounding |
| From: | "Treff, Arthur" <Arthur.Treff(at)Smartm.com> |
Bob,
I just got off the phone with Whelen regarding power requirements of the A413A.HDA-CF-14.
This is the power supply that operates 3 strobe lights simultaneously.
According to the installation sheet, Outlet 1 produces 42 Joules and alternates
with strobe outlets 3 & 4 which are producing 21 Joules apiece (or 42 joules).
The Whelen tech said that this unit requires 7 amps continuously. When
I asked him to go thru the calculations of Watt/seconds with me to prove it,
he just said that the alternator will see 7 additional amps when strobes are
switched on. I don't think he knew what a Joule really was, he further stated
the inrush current was alot higher (but he didn't know what that value was),
but that it's duration was too small to be of concern. He said that the wire
size and fuse should be for 10-15 amps. I'm not sure I agree, see my reasoning
below.
I am using your analysis in the Connection page12-12 of 70 flashes per minute.
I did not confirm this with Whenen. So, if we assume that the strobe outlets
produce a flash once every 860 milliseconds, then Outlets 3 42 watt/seconds divided
by .86 seconds is 48 watts, or 4 amps in a 12 volt system. This 4 amp
"event" is alternating with Outlet 1. Therefore, the power pack is drawing 4
amps continuously, am I right?
1) So, my question is one of alternator load. This 4 amps that is alternating
between outlet 1 and 2/3, is it additive for a continuous load of 8 amps, or
is it 4 amps? Additionally, I'll size my fuse to be 10 amps and the wire accordingly
for round trip length.
2) For grounding, I plan on running the strobe power supply ground forward to
the instrument panel ground "forest of tabs" to avoid spurious ground loops in
the airframe, correctamundo?
Thanks for all your devotion providing sage advice to guys like me who are all
mechanical and not much upstairs electrically..
Arthur Treff
RV-8 N666AT (reserved)
Asheville, NC
________________________________________________________________________________
| Subject: | Re: Source for Brass Bolt |
I dont know if they have it in brass, but Ive bought 3/4-10 silicon bronze
bolts from these guys. They carry a lot of hardware for small boat builders.
Mess around a sailboat for awhile then move to an airplane and you begin to
notice they are more alike than they are different.
http://www.jamestowndistributors.com/
________________________________________________________________________________
| Subject: | relay diode soldering |
Hi Bob and all,
Is it a good practice to solder the diode direct across the faston lugs of a
relay ? (as opposed to installing it with crimp terminals).
I've seen our kit factory do it that way, and I was wondering.
Thanks
Gilles
________________________________________________________________________________
| Subject: | Circuit protection question |
Hi Bob and all,
Please allow me to ask again a question that may have remained unnoticed.
Thanks in advance,
Gilles
See below :
----- Message d'origine -----
De : "Gilles.Thesee" <Gilles.Thesee@ac-grenoble.fr>
:
Envoy : lundi 28 avril 2003 19:11
Objet : AeroElectric-List: Circuit protection question
<Gilles.Thesee@ac-grenoble.fr>
>
> Hi Bob and all,
>
> I started the wiring for real last week. No hassles except keeping those
> wire coils clear. Oh, and a 'crimper elbow' !
>
> Here is my question :
> We're using some parts supplied by the kit manufacturer for the flaps
> control and motors.
> They say they wire with 16 AWG, despite the fact they use a 25 amp
breaker.
>
> My intention is to use a fuse, and fatter wires.
> Does it make sense to use 14 AWG wires, since the 25 amp protection is
only
> there for the very momentary inrush current draw ?
> And do I add a 18 AWG fuselink in case of faulted wire or shorted motor ?
>
> Thanks,
>
> Gilles Thesee
________________________________________________________________________________
| Subject: | Re: Z-13 and Dual Electronic Ignitions |
| From: | Joel Harding <cajole76(at)ispwest.com> |
Norm,
I have been contemplating many of the same ideas you just presented. I
started out with Z-11 and added dual electronic ignitions. Then I took
the Lightspeed recommendation to install a small 4.5 A H aux battery as
a backup for one of the ignitions, and started thinking about using it
as a second power source for the essential bus. But then, like you I
began thinking why not install a disconnect between the main and
essential bus and use it as like an avionics bus since most of the same
items would be on both.
The questions I have are:
1. What are the negative consequences of installing a switch between
the main and essential buses?
2. Is a contactor needed with the small aux battery?
Joel Harding
On Thursday, May 8, 2003, at 10:25 AM, Muzzy Norman E wrote:
>
>
> I will run with a 40A alternator and an SD-8 for engine driven power
> sources, and a pair of electronic ignition systems (no mags). The Z-13
> diagram lays out the architecture for the SD-8 and L40 charging system
> with
> one battery. I could wire my ignition systems directly to the Battery
> bus
> as shown. It has been said several times that an electrically
> dependent
> ignition design really deserves two batteries. So, where do we go to
> achieve this?
>
> We could adopt the architecture of Z-14 but use the SD-8 as a second
> alternator. One of the challenges with this architecture is that it
> requires a minimum of two contactors to power the busses where the
> essential
> items reside. The ignition systems would be located one each on the
> battery
> busses. I think that Z-14 makes sense with two big alternators, but
> may not
> be optimized for the SD-8.
>
> Or, we could add an additional battery to Z-13 using Figure Z-30. In
> this
> manner, we can run the essential bus philosophy, with an additional
> battery
> that could be isolated from the rest of the charging system. In order
> to
> supply the essential bus from the second battery, we need to modify
> how the
> essential bus is powered. As soon as you do that, it begins to smell
> a lot
> like an avionics bus, which can be powered from either Battery 1 or
> Battery
> 2. We can: A) leave it as is, with the diode to one of the main busses
> and
> alt feed from the same battery. B) use a 3 position switch as a
> selector
> between the two batteries (There's that avionics bus smell again...),
> eliminate the diode (to prevent tying the batteries together during
> starting
> if the alt feed switch were on, or if one of the battery busses were
> somehow
> pulled close to ground).
>
> While we are considering how to tie this second battery in, we are also
> being reminded that using lightweight washers instead of standard
> washers
> could save a few ounces on your airframe. And that adding weight is
> even
> worse than installing a split master switch! So, that little voice in
> the
> back of our head encourages us to install the Z-13 system with a single
> battery and save the weight.
>
> My gut tells me to add a second battery to the Z-13 architecture,
> using the
> Z-30 technique. Tie the E-bus to the Battery bus that is associated
> with
> the SD-8.
>
> I suspect that I am not alone in debating these possibilities, and
> would
> like to here some discussion on what would be the appropriate manner to
> handle feeding the E-bus.
>
> Regards-
> Norm
>
>
> _-
> ======================================================================
> _-
> ======================================================================
> _-
> ======================================================================
> _-
> ======================================================================
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Builder documentation on the Web-summary |
>
>
>I received 13 excellent, helpful replies to my request for "how to create
>drawings, sketches, & tables viewable on a web site". Thank you all.
>
>Here's a summary of what I learned:
>
>1. Drawings made by CAD programs (Autocad, Intellicad-an Autocad "full
>features clone" (I have Airplane PDQ which has full Intellicad embedded):
> a. File, Export to File, in the Save As box navigate to the desired
> folder, use or change the file name, then go to File Type & scroll down
> to & select .bmp; that all disappears and you are back in Intellicad with
> the "Selection Menu" box popped up - click "select all" then press
> "Enter" (a non-intuitive response to a command line question) and in a
> short moment the conversion is completed.
> b. Then use Paint (MSPAINT) to open the file & immediately Save As a
> .jpg Everyone with Windows has Microsoft's "Paint" for this .bmp
> to .jpg conversion. And everyone with Windows has Kodak's "Imaging"
> program that views .jpgs, plus .jpg files/images are imbedded directly
> into aweb page and thus viewable by a browser.
> (interesting side note: My "Imaging" pgm won't let me save anything
> as .jpg . . . weird.)
>
>2. Non-cad drawings and sketches (fuel system, simple electrical
>schematics or wire diagrams, etc)
> a. Hand draw and color sketches and simply scan them as .jpg files
> to insert into web page; or,
> b. Use "Paint" (MSPAINT.EXE in Programs, Accessories) for Sketches -
> c. Excel has a "drawing" mode with lots of features.
> - Another lister several months ago shared how he used Excel to
> "draw" a very neat electrical schematic.
> - My impression is that one would be able to "draw" a neater,
> more detailed drawing than using PAINT - maybe easier, too, since Exel
> has more drawing features than the rudimentary lines, rectangle, and
> "free hand with a mouse" of PAINT.
Better yet. Get Adobe Acrobat. It's for sale all over ebay and other
places on the 'net. Acrobat fools your computer into thinking that
it is a printer . . . you can "print" to Acrobat and instead of getting
paper out of a printer, you get .pdf file on your hard drive.
>Other tips (summary listing):
>1. Eric M. Jones: If you have an interest in CAD, please see
>http://www.tenlinks.com/CAD/products/free/cad.htm. This is a repository of
>all things in free cad, and add-ons too
>
>2. Chris Good: Powerpoint has an "export to html" function that creates
>the pages on the web site.
>
>3. Ernest Christley: Try "The Gimp". There is a version for Windo[ws]
> It's a Photoshop wannabe, that will cost you exactly $0. You'll be
>able to work on the JPG files and do lots of other neat things if you'll
>just spend a few hours with the included documentation. As a bonus, the
>JPG files it produces tend to be about 1/4th the size of what my digital
>camera program produces.
>
>4. Dale Smith: "jpeg optimizer" will trim your photos' file size
>literally to any size you like, all the while showing you in a window what
>the downsized picture file looks like! ... it's shareware located for
>download on CNet at: http://download.com.com/3000-2192-9623164.html
> - File sizes a third of the original show with almost negligible
> differences. If it does degrade, just kick it up a few percent. You
> don't need to re-size most pics down to enjoy the benefits, but cropping
> out the unneeded always helps keep the filesize in check.
>
>5. Rob Housman: Use "FinePrint" to save the file in Adobe Acrobat's pdf
>format. Go to www.fineprint.com and download the free version of that
>program. [ This sounds like one to get familiar with. ]
>
>6. Dan Checkoway: There are plenty of forums and self-teach web sites
>out there for web development. See http://www.w3schools.com, for
>example. [ I went to this and will use it as my primary learning tool for
>web stuff.]
>
>7. Joshua Siler: Adobe Photoshop and Illustrator, with a tablet input
>device, are the
>best ways to do this [sketches]. However they are quite expensive.
> - Try Paint Shop Pro 8.0 - you can find it at http://www.download.com
> . It will let you create an
>image, and then you can save it as a file format that windows can read.
Our CD Rom has three Autocad compatible drafting programs on
it. You can download from the website at
http://216.55.140.222/CD/AEC8_0.zip
or purchase at http://www.aeroelectric.com/Catalog/AECcatalog.htm
Acrobat reader is free to everybody. Your published works will be easily
read and printed. I often publish .jpg photos to .pdf files just to insure
the manner in which they are displayed and printed. The REALLY neat thing
about going the Adobe route is that Acrobat allows you to edit multiple
.pdf files together. For example,
http://216.55.140.222/temp/Audio_Prelim.pdf
contains pages of data that were generated on three different applications:
Autocad.dwg, camera.jpg, and ECB layout.jpg. I could easily have included
pages of word processor text and maybe even pages from a .pdf file
generated
by another source. Very, VERY powerful and easy on your readers.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Whelen strobe current draw and grounding |
>
>
>Bob,
>I just got off the phone with Whelen regarding power requirements of the
>A413A.HDA-CF-14. This is the power supply that operates 3 strobe lights
>simultaneously. According to the installation sheet, Outlet 1 produces 42
>Joules and alternates with strobe outlets 3 & 4 which are producing 21
>Joules apiece (or 42 joules). The Whelen tech said that this unit
>requires 7 amps continuously. When I asked him to go thru the
>calculations of Watt/seconds with me to prove it, he just said that the
>alternator will see 7 additional amps when strobes are switched on. I
>don't think he knew what a Joule really was, he further stated the inrush
>current was alot higher (but he didn't know what that value was), but that
>it's duration was too small to be of concern. He said that the wire size
>and fuse should be for 10-15 amps. I'm not sure I agree, see my reasoning
>below.
>
>I am using your analysis in the Connection page12-12 of 70 flashes per
>minute. I did not confirm this with Whenen. So, if we assume that the
>strobe outlets produce a flash once every 860 milliseconds, then Outlets 3
>42 watt/seconds divided by .86 seconds is 48 watts, or 4 amps in a 12 volt
>system. This 4 amp "event" is alternating with Outlet 1. Therefore, the
>power pack is drawing 4 amps continuously, am I right?
Sounds pretty good . . . actually, you have a 14v system so the
current is likely to be lower yet.
>1) So, my question is one of alternator load. This 4 amps that is
>alternating between outlet 1 and 2/3, is it additive for a continuous load
>of 8 amps, or is it 4 amps? Additionally, I'll size my fuse to be 10 amps
>and the wire accordingly for round trip length.
7A fuse and 20AWG wire would be just fine.
>2) For grounding, I plan on running the strobe power supply ground
>forward to the instrument panel ground "forest of tabs" to avoid spurious
>ground loops in the airframe, correctamundo?
You can ground locally. This is often done and as long
as all the potential victims are grounded at the tabs,
whatever noise the strobe puts into the airframe can't
get at the victims anyhow.
>Thanks for all your devotion providing sage advice to guys like me who are
>all mechanical and not much upstairs electrically..
When you've deduced more about Whelen's product than they can
tell you . . . you're doin' better than most.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Circuit protection question |
><Gilles.Thesee@ac-grenoble.fr>
>
>Hi Bob and all,
>
>Please allow me to ask again a question that may have remained unnoticed.
>Thanks in advance,
>
>Gilles
>
>See below :
>
>----- Message d'origine -----
>De : "Gilles.Thesee" <Gilles.Thesee@ac-grenoble.fr>
> :
>Envoy : lundi 28 avril 2003 19:11
>Objet : AeroElectric-List: Circuit protection question
>
>
><Gilles.Thesee@ac-grenoble.fr>
> >
> > Hi Bob and all,
> >
> > I started the wiring for real last week. No hassles except keeping those
> > wire coils clear. Oh, and a 'crimper elbow' !
> >
> > Here is my question :
> > We're using some parts supplied by the kit manufacturer for the flaps
> > control and motors.
> > They say they wire with 16 AWG, despite the fact they use a 25 amp
>breaker.
The flap system on a King Air doesn't draw
that much power. This doesn't sound like the
folks who did the kit backed up their suggestions
with any research.
> >
> > My intention is to use a fuse, and fatter wires.
> > Does it make sense to use 14 AWG wires, since the 25 amp protection is
>only
> > there for the very momentary inrush current draw ?
> > And do I add a 18 AWG fuselink in case of faulted wire or shorted motor ?
No, fuses are always MUCH faster than breakers and
faster still than fusible links. Wire it with 16AWG
and fuse it at 10A and go fly. I'll bet you don't pop
the 10A fuse. Try flying for awhile on a 7A fuse. I'll
bet it doesn't pop either.
Bob . . .
________________________________________________________________________________
| Subject: | LR3B Warning Light |
Bob,
Quick dumb question. LR3B instructions state that the low voltage
warning lamp is a "midget flanged #330 bulb". Is there something special
about it's specifications, or may any small 12V incandescent warning light be
substituted?
Thanks
Dan Horton
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: relay diode soldering |
><Gilles.Thesee@ac-grenoble.fr>
>
>Hi Bob and all,
>
>Is it a good practice to solder the diode direct across the faston lugs of a
>relay ? (as opposed to installing it with crimp terminals).
>I've seen our kit factory do it that way, and I was wondering.
>
>Thanks
>
>Gilles
Not sure it matters much. If the relay case plastic
will let you do it without distorting the terminal
mounting, soldering is probably okay.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Circuit protection question |
> > > They say they wire with 16 AWG, despite the fact they use a 25 amp
> >breaker.
>
> The flap system on a King Air doesn't draw
> that much power. This doesn't sound like the
> folks who did the kit backed up their suggestions
> with any research.
>
> > >
> > > My intention is to use a fuse, and fatter wires.
> > > Does it make sense to use 14 AWG wires, since the 25 amp protection is
> >only
> > > there for the very momentary inrush current draw ?
> > > And do I add a 18 AWG fuselink in case of faulted wire or shorted
motor ?
>
> No, fuses are always MUCH faster than breakers and
> faster still than fusible links. Wire it with 16AWG
> and fuse it at 10A and go fly. I'll bet you don't pop
> the 10A fuse. Try flying for awhile on a 7A fuse. I'll
> bet it doesn't pop either.
>
> Bob . . .
Bob,
Thanks for answering.
Our problem is, we'd like to eliminate the risk of nuisance trip.
In the landing position the flaps are VERY powerful, and in case of failure
to retract in a go around we'd be in trouble for real.
They are using 4 small 35 watt Bosch motors that are rated at 10 amps
nominal current each, according to Bosch's scarce documentation.
They are using a similart motor for the pitch trim and they use to protect
the trim circuit with a 10 amp breaker.
Seems a lot of amps, but we are stuck with the motors.
Now since I told him the fuses are faster than the breakers, my friend is
talking of using a resettable breaker, 'just in case'.
That's why I suggested using a fuselink and fatter wires. What should I do
to reassure him ?
Thanks,
Gilles
________________________________________________________________________________
| Subject: | Circuit protection question follow on |
> > > > And do I add a 18 AWG fuselink in case of faulted wire or shorted
> motor ?
> >
> > No, fuses are always MUCH faster than breakers and
> > faster still than fusible links. Wire it with 16AWG
> > and fuse it at 10A and go fly. I'll bet you don't pop
> > the 10A fuse. Try flying for awhile on a 7A fuse. I'll
> > bet it doesn't pop either.
> >
> > Bob . . .
>
>
> Bob,
>
> Thanks for answering.
> Our problem is, we'd like to eliminate the risk of nuisance trip.
> In the landing position the flaps are VERY powerful, and in case of
failure
> to retract in a go around we'd be in trouble for real.
> They are using 4 small 35 watt Bosch motors that are rated at 10 amps
> nominal current each, according to Bosch's scarce documentation.
> They are using a similart motor for the pitch trim and they use to protect
> the trim circuit with a 10 amp breaker.
> Seems a lot of amps, but we are stuck with the motors.
> Now since I told him the fuses are faster than the breakers, my friend is
> talking of using a resettable breaker, 'just in case'.
> That's why I suggested using a fuselink and fatter wires. What should I do
> to reassure him ?
>
> Thanks,
>
> Gilles
Bob and all,
I just succeeded in calling the electrician who devised the flap system. He
is now wortking in an FBO in Luxemburg.
Here's a summary of what he said :
-Yes the inrush current is in the order of 20 amps.
-Yes the 16 AWG wire is a bit weak considering the 25 amp protection. But
his boss was reluctant to buy another reel of larger wire !
-The 14 AWG would definitely be bettter.
Now here's my new question :
Aren't we in a case fairly similar to the Hyd pump ? And then, would'nt it
make sense to go the fuselink only route ? So we'd stick to the 'Connection
philosophy while eliminating the risk of nuisance trip.
Bob, where am I wrong ?
Thanks,
Gilles
________________________________________________________________________________
| From: | "William Bernard" <billbernard(at)worldnet.att.net> |
| Subject: | Re: Source for Brass Bolt |
Thanks for all the suggestions. As it turns out, I got a 3/8" x 1" bolt at the
electrical supply house. It was used in the clamp on a ground rod. They had a
couple extra, so I didn't have to buy the whole clamp.
Looks like it will work great.
Thanks for the suggestions.
Bill
________________________________________________________________________________
| From: | Jim Oke <wjoke(at)shaw.ca> |
| Subject: | Re: Source for Brass Bolt |
Bill;
The plumbing industry uses 5/16" brass bolts for toilet bowl hold downs and
for attaching the tank to the bowl. Check the plumbing department at Home
depot or a similar outlet. Watch for cheaper plated steel bolts instead of
pure brass ones though.
Jim Oke
Winnipeg, MB
RV-6A C-GKGZ (waiting for final inspec.)
----- Original Message -----
From: "William Bernard" <billbernard(at)worldnet.att.net>
Subject: AeroElectric-List: Source for Brass Bolt
>
> I'm trying to follow Bob's recommendation to use a 5/16" (or bigger)brass
bolt to get the ground wire through the firewall. I need to get the wire up
from the bottom of the aircraft around a large fuel tank mounted near the
firewall, up to the top where the ground buss is located.
>
> Does anyone have a source for a 5/16" bolt? The biggest I've been able to
locate so far is 1/4".
>
> Thanks for the help.
>
> Bill
>
>
________________________________________________________________________________
| From: | Neil Clayton <harvey4(at)earthlink.net> |
| Subject: | Tach P-lead feed |
Van's sells in nice electronic analogue tach that I think I'll use, but the
description says it works off the mag "P" lead.
How would I wire it to take it's feed from both mag P-leads so that I can
do a mag-drop test at run up time and still get a signal when I switch from
one mag to the other?
Thanks
Neil
________________________________________________________________________________
| From: | "Treff, Arthur" <Arthur.Treff(at)Smartm.com> |
Listers,
I'm looking for a 12V DPDT relay to switch a WigWag function on and off with an
INfinity stick grip switch. Any ideas on a source?
Arthur Treff
Asheville, NC
RV-8 N666AT (reserved)
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Circuit protection question follow on |
><Gilles.Thesee@ac-grenoble.fr>
>
>
> > > > > And do I add a 18 AWG fuselink in case of faulted wire or shorted
> > motor ?
> > >
> > > No, fuses are always MUCH faster than breakers and
> > > faster still than fusible links. Wire it with 16AWG
> > > and fuse it at 10A and go fly. I'll bet you don't pop
> > > the 10A fuse. Try flying for awhile on a 7A fuse. I'll
> > > bet it doesn't pop either.
> > >
> > > Bob . . .
> >
> >
> > Bob,
> >
> > Thanks for answering.
> > Our problem is, we'd like to eliminate the risk of nuisance trip.
> > In the landing position the flaps are VERY powerful, and in case of
>failure
> > to retract in a go around we'd be in trouble for real.
Understand . . . and this is precisely the reason that the
folks who are supplying this system to you should take the time
to
> > They are using 4 small 35 watt Bosch motors that are rated at 10 amps
> > nominal current each, according to Bosch's scarce documentation.
4 motors in a flap system? Why? How are they synchronized
with each other?
Is there a website that describes this system?
> > They are using a similart motor for the pitch trim and they use to protect
> > the trim circuit with a 10 amp breaker.
> > Seems a lot of amps, but we are stuck with the motors.
> > Now since I told him the fuses are faster than the breakers, my friend is
> > talking of using a resettable breaker, 'just in case'.
> > That's why I suggested using a fuselink and fatter wires. What should I do
> > to reassure him ?
It doesn't matter if you have one motor or 4 . . . IF
full flap extension puts you at-risk for go-around
performance . . . then you should write POH
procedures that call for NOT extending flaps beyond
comfortable go-around settings until on VERY short final.
The early C-150's had infamous "barn door" flaps that
would extend to a setting of 40 degrees. More than
one C-150 pilot made an unplanned/unwanted contact
with the earth when circumstances found him too low,
too slow and too much flaps. There was an AD
issued to limit flap travel on these aircraft to
30 degrees . . . and that was still pretty tense
at gross on a warm day.
Your friend is worrying about the wrong thing. If
the flap system can EVER fail in ANY way, then you
need to operate the airplane in a manner that mitigates
risk. Remember, all other things held constant, system
reliability is inversely proportional to system
parts count; with 4 motors, your are 4x more likely to have
a system failure than with one motor. Wire and
fuse size are WAY down on the list of concerns.
Will failure of a single motor produce asymmetrical
flap extension? There's a 4-motor system on Eclipse
and an 8-motor flap system on Premier. There was about
5 times more work to make sure the system was fail
safe than work required to make them function
normally. Be careful about what you are led to
believe about this system. I am VERY skeptical.
> >
> > Thanks,
> >
> > Gilles
>
>Bob and all,
>
>I just succeeded in calling the electrician who devised the flap system. He
>is now wortking in an FBO in Luxemburg.
>Here's a summary of what he said :
>
>-Yes the inrush current is in the order of 20 amps.
Yes . . . ALL motors and ALL lamps have a startup inrush current
that is 3-20 times the running current but these currents last
only for very short periods of time . . .that's why they call
them "inrush" currents.
Went to the workbench and plotted the current/voltage curve
for an H4352 headlamp. You can download the data plot at
http://216.55.140.222/temp/4352_Headlamp.pdf
Note that as current rises from 0 mA, the line is fairly
straight. At 600 mA, the voltage drop is 155 mV which
translates to a resistance of 260 milliohms. It's easy
to see that if we were to increase terminal voltage at
the lamp to 14v, the current through the lamp would be
56 Amps! Hmmm . . . this is a 55 Watt lamp so at 14.0 volts
we would expect 3.9 Amps . . . and indeed, a few hundred
milliseconds after the lamp is turned on, the temperature
rise is so great as to reduce current draw into the normal
operating range.
Another interesting data point gleaned from this
experiment. Looking directly at the lamp's filament,
it was up to dull red glow temperatures (800 degrees
plus?) with only 1.0 Volts applied. At this point
on the curve, it was drawing only 1.5 Amps for
a power consumption value of 1.5 Watts. This
underscores the very steep positive temperature
coefficient of resistance. This lamp was at about
33% normal operating temperature with only 3%
of normal operating power applied!
Motors have a similar characteristic. A pitch
trim motor on the Beechjet draws about 2 Amps
under normal loads. In-situ inrush currents have been
measured at over 12 Amps. This is mitigated by additional
resistance of ship's wiring. If we put 28 Volts right on
the motor terminals, I would expect inrush currents on
the order of 20 Amps. The Beechjet's trim motor has an
acceleration time constant of about 300 mSeconds. So
after about 1 second, the motor is operating within
a few percent of normal operating current.
Should we fuse the 4352 lamp at 60A and wire it with
4AWG wire? The Beechjet's trim system at 10A? No,
like the devices they protect, fuses and breakers have
time constants too. Thermal devices have what is called
an I(squared)*T constant. Generally speaking, if you
double the current through the device, it can be
expected to open in 1/4th the time. Further, the
experiment cited above shows how strongly system
wiring can mitigate inrush currents.
While at the bench, I took the same lamp and powered
it from a 17 a.h. battery through very short test
leads and plotted the inrush currents on a 'scope.
I found that the inrush current peaked at 38 amps
(See . . . internal resistance of battery combined with
resistance of shunt and test leads mitigated a 56
Amp theoretical inrush down to 38 amps!) The time
constant for current on this lamp was observed at
70 mSeconds. This means that it took much less than
a 300 mSeconds for the lamp to reach full operating
temperature. Way below the I(squared)*T value
that puts a 5A fuse at risk.
Is the protection circuit in danger of operating during
normal inrush? Sometimes . . . you can't use the very
fast magnetic breakers on motors and big lamps without
consideration of their ability to detect and operate
on short duration overloads. Thermal devices like fuses
are much slower, breakers slower still, limiters like
the ANL devices recommended for alternators are virtual
snails with respect to response time.
>-Yes the 16 AWG wire is a bit weak considering the 25 amp protection. But
>his boss was reluctant to buy another reel of larger wire!
Typical program manager . . . bottom-line investment
considerations drive decisions best left to engineers.
This is an excellent illustration of a point I've
tried to make many times here on the list. There is
no better data than that which is gathered by the
repeatable experiment. Any of you with access to the
equipment can repeat what I've measured above and
confirm both my methodology and analysis. I'll bet
the folks who supply the flap motor to your project
don't have a 'scope nor have they conducted the
experiments that allow them to size wires and
circuit protection with confidence . . . they're
operating in the, "if 10A/16AWG is good, 25A/12AWG
is better mode."
You need to ask your flap system supplier about
their data from an experiment you might want
to repeat on your airplane.
>-The 14 AWG would definitely be bettter.
>
>Now here's my new question :
>Aren't we in a case fairly similar to the Hyd pump ? And then, would'nt it
>make sense to go the fuselink only route ? So we'd stick to the 'Connection
>philosophy while eliminating the risk of nuisance trip.
>Bob, where am I wrong ?
You're not wrong . . . I am skeptical of the
understanding of physics by people who are advising
you.
I would encourage you to forward a copy of this
note to the supplier of your flap system. If they
perceive it to be the helpful suggestion it is
intended to be, they'll take time to learn more
about operational details of their product.
Given what you've told us today, there are system
operation and safety issues that run far beyond
worries about wire and fuses. Let's talk some
more. Is this the ONLY option you have for flap
system operation?
By the way, there was a discussion over the last
few days about web publishing. When this message
came up on the list, it took about 5 minutes to
gather data at the bench, 5 minutes to plot it to
AutoCAD, 1 minute to "print" to Adobe Acrobat
and another minute to write it to the /temp
directory on aeroelectric.com . . . . pretty
powerful, effective and easy to use tools.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Source for Brass Bolt |
>
>Bill;
>
>The plumbing industry uses 5/16" brass bolts for toilet bowl hold downs and
>for attaching the tank to the bowl. Check the plumbing department at Home
>depot or a similar outlet. Watch for cheaper plated steel bolts instead of
>pure brass ones though.
I've used plumbing hardware with the only disappointment
being the coarse threads. Jim makes a good point. Use
only bare brass hardware. Plating increases resistance
and may hide the fact that the hardware is not brass.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: LR3B Warning Light |
>
>Bob,
> Quick dumb question. LR3B instructions state that the low voltage
>warning lamp is a "midget flanged #330 bulb". Is there something special
>about it's specifications, or may any small 12V incandescent warning light be
>substituted?
>
>Thanks
>Dan Horton
Any 12v lamp can be substituted.
Bob . . .
________________________________________________________________________________
| From: | MikeEasley(at)aol.com |
| Subject: | Shielding of Alternator and Magneto Wires |
I participated in a debate with a couple composite builders and myself
yesterday about which alternator wires should be shielded. I spoke up and
said, "According the Aeroelectric Connection you don't need to shield any of
the field or B-lead wires. So they pulled out diagrams from their panel
builders, and Firewall Forward and the debate began.
The diagram from the panel builder showed the alternator field wires
grounded, one builder said to use shielded wire on the alternator B lead.
I read about shielding my magneto P leads, but I couldn't find anything in
Aeroelectric Connection about shielding any alternator wires. I ran
unshielded wire on my plane to the alternators.
Please confirm that I'm not building a noisy airplane.
Thanks,
Mike Easley
Lancair ES
________________________________________________________________________________
| From: | "Phil Birkelbach" <phil(at)petrasoft.net> |
| Subject: | Re: Circuit protection question |
> Bob,
>
> Thanks for answering.
> Our problem is, we'd like to eliminate the risk of nuisance trip.
> In the landing position the flaps are VERY powerful, and in case of
failure
> to retract in a go around we'd be in trouble for real.
> They are using 4 small 35 watt Bosch motors that are rated at 10 amps
> nominal current each, according to Bosch's scarce documentation.
> They are using a similart motor for the pitch trim and they use to protect
> the trim circuit with a 10 amp breaker.
> Seems a lot of amps, but we are stuck with the motors.
> Now since I told him the fuses are faster than the breakers, my friend is
> talking of using a resettable breaker, 'just in case'.
> That's why I suggested using a fuselink and fatter wires. What should I do
> to reassure him ?
>
> Thanks,
>
> Gilles
>
35 Watts pulling 10 Amps???? That ain't right. There are fuses that are
designed for highly inductive loads that will not blow as fast. I don't
know right off hand what the specs are but there are hundreds of different
ratings for fuses out there. You may have to use regular glass fuses and
not the automotive type blade fuses but you could do it.
All in all I bet Bob is right. Run 16AWG wire fuse it with a 10A fuse and
you'll never have to think about it again. If in doubt test it rigorously
on the ground. Put the flaps under load (hold them with your hand) and run
the motors. Put a good Recording DVM on them and see what you get for max
current.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
________________________________________________________________________________
| From: | "Shaun Simpkins" <shauns(at)hevanet.com> |
| Subject: | Re: Whelen strobe circuit current draw and grounding |
Gents:
Don't forget power supply efficiency!
The Whelen guy you talked to may not have sounded knowledgeable, but
the Whelen guy who designed the power supply may have known what he
was doing when he spec'd the current draw.
Although the calculation you performed was correct for the average current
demanded by the strobe tube (assuming all tube input energy was converted into
light), it did not take into account the efficiency of the DC-DC converter driving
the thing.
Modern designs can have efficiencies over 90%, but the design that Whelen is
using might not be that good ( TSO stagnation strikes again ).
I posed this same question to Whelen 2 years ago. For some reason, I got through
to one of their design engineers. He estimated that their supply was at best 80%
efficient - which means that it takes at least 5A input to get 4A out.
The manufacturer's typical spec may cover a multitude of unknowns.
Operating temperature, humidity, aging...all legitimate.
After all, the objective of the company is to guarantee the smallest set of specs
that ensure proper usage of the product under all foreseeable conditions
and minimize their liability.
It would be great if Whelen just published power supply demand limits and
typicals for each operating mode. If the strobe power drain is that critical for
your project,
nothing beats actually measuring its current draw.
Shaun
________________________________________________________________________________
| From: | "Dennis O'Connor" <doconnor(at)chartermi.net> |
| Subject: | Re: Whelen strobe circuit current draw and grounding |
Bingo!
Denny
If the strobe power drain is that critical for your project,
> nothing beats actually measuring its current draw.
>
> Shaun
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Whelen strobe circuit current draw and grounding |
>
>Gents:
>
>Don't forget power supply efficiency!
>
>The Whelen guy you talked to may not have sounded knowledgeable, but
>the Whelen guy who designed the power supply may have known what he
>was doing when he spec'd the current draw.
Probably did but how did he convey it? Peak current? Average
current? Integrated current? Given the periodic nature of
power emission from the flash tubes, one can rightly expect
a periodic fluctuation in power input wherein AREA UNDER THE
CURRENT curve is integrated current and the true value of
energy demand on the ship's system.
I can tell you that no salesperson at RAC can answer any
similar line of questioning on the part of one of our
customers. I would hope he/she would refer to the question
to the cognizant engineer . . . but in my total tenure
at three airframe companies, I think I may have talked
to a customer once or twice.
>Although the calculation you performed was correct for the average current
>demanded by the strobe tube (assuming all tube input energy was converted into
>light), it did not take into account the efficiency of the DC-DC converter
>driving the thing.
>Modern designs can have efficiencies over 90%, but the design that Whelen is
>using might not be that good ( TSO stagnation strikes again ).
>
>I posed this same question to Whelen 2 years ago. For some reason, I got
>through
>to one of their design engineers. He estimated that their supply was at
>best 80%
>efficient - which means that it takes at least 5A input to get 4A out.
>
>The manufacturer's typical spec may cover a multitude of unknowns.
>Operating temperature, humidity, aging...all legitimate.
>After all, the objective of the company is to guarantee the smallest set
>of specs
>that ensure proper usage of the product under all foreseeable conditions
>and minimize their liability.
>
>It would be great if Whelen just published power supply demand limits and
>typicals for each operating mode. If the strobe power drain is that
>critical for your project,
>nothing beats actually measuring its current draw.
Yup, did such a study on a builder's proposed
strobe light a few years ago. We were looking at both
noise and the periodic, erratic nature of input current
draw for his power supply. See the plot of this
data at:
http://216.55.140.222/temp/Strobe_Plot.pdf
Here one may observe the effects of various filter
techniques tried for noise mitigation. The top
plot is current curve using one of the radio shack
filters as described in:
http://www.aeroelectric.com/articles/filter/filter.html
The second plot places a single 10,000 uf cap across
the power supply input.
The third plot shows unfiltered current noise.
In the second plot, we see a data value deduced from
area under the current curve that says this strobe
uses 1.3 ampere seconds of current per cycle. The
ENERGY consumed by this particular strobe is
1.3 a-s/flash x 14v = 18.2 Joules/flash input power.
I think this was a 10 Joule/flash system so this
puts overall efficiency at about 55%. Probably
average for products of this type.
The peak current was measured at 2.7 amps. Average
current is 0.9 x 1.3 or 1.17 amps. I seem to recall
the instructions for this system called for a 5A
breaker . . . a 2A breaker would probably have worked
nicely too.
Bob . . .
________________________________________________________________________________
| From: | "David Carter" <dcarter(at)datarecall.net> |
| Subject: | Documentation methods-CAD pgm to plot data, then print |
.pdf
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: AeroElectric-List: Re: Circuit protection question follow on
<< BIG snip >>
> By the way, there was a discussion over the last
> few days about web publishing. When this message
> came up on the list, it took about 5 minutes to
> gather data at the bench, 5 minutes to plot it to
> AutoCAD, 1 minute to "print" to Adobe Acrobat
> and another minute to write it to the /temp
> directory on aeroelectric.com . . . . pretty
> powerful, effective and easy to use tools.
>
> Bob . . .
Bob,
First topic of two: While jogging this morning, was trying to digest/deduce
meaning of what you said yesterday about "fooling the computer into thinking
that Adobe was a printer". Since I don't YET have Adobe Acrobat (only have
Reader), I don't know the interface and menu choices and set-up on a typical
Windows system, thus the following question(s):
1. If I have a .dwg or .dxf AutoCAD drawing I want to convert to .pdf,
and IF/WHEN I have Adobe Acrobat, what are the "clicks"?
-- For example, when Adobe Acrobat is first installed, is there a
new "printer" icon installed called "Adobe" (along with my existing Canon
blk & white hooked to my computer and my wife's color printer hooked to her
computer on other end of our LAN) which I print my file to so it gets
"printed" to the HD as a .pdf file (converted from whatever file type I
tried to print)?
-- Likewise, if I have a .jpg file I want to convert to .pdf, do I
just "print" it to Adobe to get the conversion?
-- If that is the procedure, which folder does it "print" to?
(When I print to a real printer, there is no "save as" dialog box - will
there be in Adobe?)
2. I looked at Kevin Horton's RV-8 Project website last night - I
nominate it as the GREATEST "builder documentation web site". He's
converted all his images to .pdf.
- I can even print his pdf documents/drawings from the website,
which I have never been able to do for any other pdf files being displayed
on the web or in a browser (the "print" option has always been "grayed out"
on other sites/files).
?? Why is it that I can't usually print other people's pdf files
being shown in a browser?
Meanwhile, I'm going to ebay and shopping for Adobe Acrobat (is that what I
want/need?)
Second topic: Plotting data with a CAD program (as opposed to plotting in
Excel).
I tried creating a data chart once on Intellicad and could not get the
desired results (I was very new to the system at that time). What are the
basic steps in Autocad for creating a chart, with X & Y axis labeling and
"units" tick marks or graph paper lines, and plotting the data?
David Carter
Nederland, Texas
RV-6
________________________________________________________________________________
| From: | "Bob Kuc" <bkuc1(at)tampabay.rr.com> |
Bob,
Did you receive the package from me?
Bob Kuc
>
> Hmmm . . . I've built dozens of these. I'm
> curious as to what's going on here. Can you send
> me your flasher assembly in the mail to look at?
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Shielding of Alternator and Magneto |
Wires
>
>I participated in a debate with a couple composite builders and myself
>yesterday about which alternator wires should be shielded. I spoke up and
>said, "According the Aeroelectric Connection you don't need to shield any of
>the field or B-lead wires. So they pulled out diagrams from their panel
>builders, and Firewall Forward and the debate began.
>
>The diagram from the panel builder showed the alternator field wires
>grounded, one builder said to use shielded wire on the alternator B lead.
Yup, Cessna shielded these leads about 1965 and whatever's
good for 100,000 Cessnas must be good for everybody. The
myth was sown in 1965 and has been watered and fertilized
well ever since. There is no basis in physics for doing this.
>I read about shielding my magneto P leads, but I couldn't find anything in
>Aeroelectric Connection about shielding any alternator wires. I ran
>unshielded wire on my plane to the alternators.
>
>Please confirm that I'm not building a noisy airplane.
You stand about 100x better chance of having noise due
to poor grounding techniques than from the lack of any
shield on an airframe system component. Don't loose any
sleep over it.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: 10519 D'Amico |
>Below is the result of your inquiry. It was submitted by
>Mike D'Amico (mike.damico(at)hp.com) on Friday, May 9, 2003 at 06:13:45
>
>Friday, May 9, 2003
>
>Mike D'Amico
>
>,
>Email: mike.damico(at)hp.com
>Comments/Questions: Hi Bob,
>
>I just receieved my order of Wig-Wag modules yesterday, and have a quick
>question. Are these solid state devices, or relay devices?
>
>I have a couple of folks that are wary of anything that is a relay device,
>such as an automobile blinker... personally, I just want something that
>works and is reliable.
>
>Thanks for your time,
I presume you're talking about the flasher that is shown
on the B&C catalog hosted on this website. That is a relay
driven by electronic timer. It's not a thermal flasher
common to most automotive applications.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | RSwanson <rswan19(at)comcast.net> |
Try http://www.jameco.com/ , they have a fairly large selection. Might
have one you could use.
R
----- Original Message -----
From: "Treff, Arthur" <Arthur.Treff(at)Smartm.com>
Subject: AeroElectric-List: DPDT relay
>
> Listers,
>
> I'm looking for a 12V DPDT relay to switch a WigWag function on and off
with an INfinity stick grip switch. Any ideas on a source?
>
> Arthur Treff
> Asheville, NC
> RV-8 N666AT (reserved)
>
>
________________________________________________________________________________
| From: | "Rick Caldwell" <racaldwell(at)hotmail.com> |
Hello All,
Anyone have experience in alternator circuit failures that could narrow down
my search?
I have a 40A B&C alternator with the LR3B-14v for control. My 5A field CB
pops. However, after a minute or so, I can reset it and it stays in, most
of the time. I have the Aeroelectric loadmeter and the load on resetting is
high but settles down to the normal 10% load after a minute or so. Adding
or cutting off loads does not seem to influence the tripping. No blown
fuses on any of the other circuits. I just installed a new Concorde 25RG-XC
battery thinking that was the problem. It wasn't. Tripped on take-off last
night. I will now start looking for intermittent shorts tomorrow. I sure
don't want to find that the LR3B is bad. I've flown 3.5 yrs with no alt.
problems until now.
Rick Caldwell
RV-6
________________________________________________________________________________
| Subject: | Documentation methods-CAD pgm to plot data, then |
print .pdf
A FREE alternative to Adobe Acrobat is FinePrint which "saves" files in the
Adobe Acrobat pdf format. Go to www.fineprint.com
to download it. The only downside to FinePrint is that it puts a one line
footer in your document giving a link to their web site.
FinePrint, and I presume Adobe Acrobat also, installs as if it were a
printer so when you want to "save" the document you actually "print" to a
file that happens to be in Adobe Acrobat format. Every installed Windows
application will have this "printer" choice available. In this respect it
is similar to fax software such as WinFax that "prints" to the fax/modem
hardware.
I can find no direct way in AutoCad 2000 LT to make a chart (other than as
text, and that would be rather tedious) but it is straightforward to make a
chart in Excel and use copy & paste to place the chart in an AutoCad
drawing.
Best regards,
Rob Housman
Europa XS Tri-Gear A070
Airfarame complete
Irvine, CA
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of David
Carter
Subject: AeroElectric-List: Documentation methods-CAD pgm to plot data, then
print .pdf
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: AeroElectric-List: Re: Circuit protection question follow on
<< BIG snip >>
> By the way, there was a discussion over the last
> few days about web publishing. When this message
> came up on the list, it took about 5 minutes to
> gather data at the bench, 5 minutes to plot it to
> AutoCAD, 1 minute to "print" to Adobe Acrobat
> and another minute to write it to the /temp
> directory on aeroelectric.com . . . . pretty
> powerful, effective and easy to use tools.
>
> Bob . . .
Bob,
First topic of two: While jogging this morning, was trying to digest/deduce
meaning of what you said yesterday about "fooling the computer into thinking
that Adobe was a printer". Since I don't YET have Adobe Acrobat (only have
Reader), I don't know the interface and menu choices and set-up on a typical
Windows system, thus the following question(s):
1. If I have a .dwg or .dxf AutoCAD drawing I want to convert to .pdf,
and IF/WHEN I have Adobe Acrobat, what are the "clicks"?
-- For example, when Adobe Acrobat is first installed, is there a
new "printer" icon installed called "Adobe" (along with my existing Canon
blk & white hooked to my computer and my wife's color printer hooked to her
computer on other end of our LAN) which I print my file to so it gets
"printed" to the HD as a .pdf file (converted from whatever file type I
tried to print)?
-- Likewise, if I have a .jpg file I want to convert to .pdf, do I
just "print" it to Adobe to get the conversion?
-- If that is the procedure, which folder does it "print" to?
(When I print to a real printer, there is no "save as" dialog box - will
there be in Adobe?)
2. I looked at Kevin Horton's RV-8 Project website last night - I
nominate it as the GREATEST "builder documentation web site". He's
converted all his images to .pdf.
- I can even print his pdf documents/drawings from the website,
which I have never been able to do for any other pdf files being displayed
on the web or in a browser (the "print" option has always been "grayed out"
on other sites/files).
?? Why is it that I can't usually print other people's pdf files
being shown in a browser?
Meanwhile, I'm going to ebay and shopping for Adobe Acrobat (is that what I
want/need?)
Second topic: Plotting data with a CAD program (as opposed to plotting in
Excel).
I tried creating a data chart once on Intellicad and could not get the
desired results (I was very new to the system at that time). What are the
basic steps in Autocad for creating a chart, with X & Y axis labeling and
"units" tick marks or graph paper lines, and plotting the data?
David Carter
Nederland, Texas
RV-6
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Alt Field Trip |
>
>
>Hello All,
>
>Anyone have experience in alternator circuit failures that could narrow down
>my search?
>
>I have a 40A B&C alternator with the LR3B-14v for control. My 5A field CB
>pops. However, after a minute or so, I can reset it and it stays in, most
>of the time. I have the Aeroelectric loadmeter and the load on resetting is
>high but settles down to the normal 10% load after a minute or so. Adding
>or cutting off loads does not seem to influence the tripping. No blown
>fuses on any of the other circuits. I just installed a new Concorde 25RG-XC
>battery thinking that was the problem. It wasn't. Tripped on take-off last
>night. I will now start looking for intermittent shorts tomorrow. I sure
>don't want to find that the LR3B is bad. I've flown 3.5 yrs with no alt.
>problems until now.
If your LR3 is that old, it may benefit from an update we
added to the that series of regulators about 2 years ago.
We had some nuisance tripping problems on some certified
ships that caused some redesign. It's a very minor change
that only a tiny percentage of customers can take advantage
off. If your voltage and current behavior of the system
is stable and "normal" for what you've been observing for
years, then I suspect you have no wiring problems that
will account for this. Call B&C and see if they'll update
your LR3 for the "nuisance trip" fix for a very reasonable
price . . . if you don't like the price, send it to me
and I'll do it.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Documentation methods to print .pdf |
>
>Bob,
>
>First topic of two: While jogging this morning, was trying to digest/deduce
>meaning of what you said yesterday about "fooling the computer into thinking
>that Adobe was a printer". Since I don't YET have Adobe Acrobat (only have
>Reader), I don't know the interface and menu choices and set-up on a typical
>Windows system, thus the following question(s):
>
> 1. If I have a .dwg or .dxf AutoCAD drawing I want to convert to .pdf,
>and IF/WHEN I have Adobe Acrobat, what are the "clicks"?
you say "plot" or "print" and then when the print menu comes up,
Acrobat Distiller will be one of your printer options in addition
to any other printers you may have installed. Select Acrobat Distiller
and then it will ask you things about paper size, landscape or portrait,
etc. Instead of spitting out image on hardware printer it asks you
what you want to name the .pdf file and where you want it stored.
If you've printed any application to a hardware printer, you can
print to Adobe Acrobat just as easily.
> -- For example, when Adobe Acrobat is first installed, is there a
>new "printer" icon installed called "Adobe" (along with my existing Canon
>blk & white hooked to my computer and my wife's color printer hooked to her
>computer on other end of our LAN) which I print my file to so it gets
>"printed" to the HD as a .pdf file (converted from whatever file type I
>tried to print)?
yup . ..
> -- Likewise, if I have a .jpg file I want to convert to .pdf, do I
>just "print" it to Adobe to get the conversion?
yup . . .
> -- If that is the procedure, which folder does it "print" to?
>(When I print to a real printer, there is no "save as" dialog box - will
>there be in Adobe?)
Adobe will ask you where to save it and what to name it . . .
> 2. I looked at Kevin Horton's RV-8 Project website last night - I
>nominate it as the GREATEST "builder documentation web site". He's
>converted all his images to .pdf.
> - I can even print his pdf documents/drawings from the website,
>which I have never been able to do for any other pdf files being displayed
>on the web or in a browser (the "print" option has always been "grayed out"
>on other sites/files).
> ?? Why is it that I can't usually print other people's pdf files
>being shown in a browser?
Make sure you have the latest freebe version of Acrobat
Reader . . although if you're going to install Acrobat
then you'll get the latest reading capability with it. Uninstall
older versions of Reader before you install Acrobat.
Also, you can eliminate lots of potential for download/display
problems if you tell your browser to download and store a .pdf
to a directory and open it with Reader or Acrobat AFTER download
is complete. This technique fixes about 90% of my readers
complaints about Adobe .pdf files.
>Meanwhile, I'm going to ebay and shopping for Adobe Acrobat (is that what I
>want/need?)
That would sure be my choice. I've used it here now for about
5 years. Except for occasional hassles with specific browser/reader
problems, it's been the most convenient and trouble free document
generator for publication. Get the latest version you can . . .
sometimes it's more economical to buy a new, unregistered copy
in an older version and then get the update from Adobe. That's
how I got my first Acrobat running . . . I think I did the whole
thing for under $150. Also consider taking an engineering student
to lunch and then dropping by the university bookstore after
lunch so he/she can buy you a latest/greatest version at the
university bookstore . . . these are QUITE reasonable too. They
say "for academic use only" to which I reply, "I don't know how
to use this and therefore I AM in the learning mode . . ."
>Second topic: Plotting data with a CAD program (as opposed to plotting in
>Excel).
> I tried creating a data chart once on Intellicad and could not get the
>desired results (I was very new to the system at that time). What are the
>basic steps in Autocad for creating a chart, with X & Y axis labeling and
>"units" tick marks or graph paper lines, and plotting the data?
Hmmm . . . this is pretty tall order for a two paragraph tutorial.
When you get ready to study AutoCAD, find a file called acad.pgp
Use a generic text editor like notepad.exe to cut and paste the
following list into the file . . . erase all existing similar looking
equivalents . . .
AR, *ARRAY
B, *BLOCK
BR, *BREAK
CI, *CIRCLE
CC, *COPYCLIP
CE, *COPYEMBED
CH, *CHAMFER
C, *CHANGE
CO, *COPY
E, *ERASE
ED, *DDEDIT
F, *FILLET
H, *HATCH
IN, *INSERT
L, *LINE
LA, *LAYER
LC, *LTSCALE
LT, *LINETYPE
M, *MOVE
MI, *MIRROR
O, *OSNAP
OF, *OFFSET
PE, *PEDIT
PG, *POLYGON
PL, *PLINE
Q, *EXIT
R, *REDRAW
RG, *REGEN
RO, *ROTATE
S, *STRETCH
SC, *SCALE
T, *TRIM
TX, *TEXT
U, *UNDO
V, *VIEW
WB, *WBLOCK
XP *EXPLODE
XT, *EXTEND
Z, *ZOOM
This is a list of 1 and 2-letter overlays for the
fully spelled out plain English command that AutoCAD
will understand. There are about 40 commands here.
AutoCAD understand virtually hundreds and hundreds
of commands . . . however, this is my personal .pgp
file that represents the commands I use about 99% of the
time. Therefore, this same list is a good study guide.
Go down the right hand column of AutoCAD commands in this
list and look them up in any study guides you may acquire.
If you learn nothing but these commands (plus a few
rudimentary houskeeping commands like "open" and "save")
you'll be getting a handle on a suite of commands that
does about everything I do with AutoCAD . . .
I ignore the pull-downs and learned how to type with
the right hand and steer the mouse with the left hand.
I found it much easier to learn and faster to use
than fiddle with those windows-like pulldowns.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Z-13 and Dual Electronic Ignitions |
>
>Norm,
>I have been contemplating many of the same ideas you just presented. I
>started out with Z-11 and added dual electronic ignitions. Then I took
>the Lightspeed recommendation to install a small 4.5 A H aux battery as
>a backup for one of the ignitions, and started thinking about using it
>as a second power source for the essential bus. But then, like you I
>began thinking why not install a disconnect between the main and
>essential bus and use it as like an avionics bus since most of the same
>items would be on both.
>The questions I have are:
>1. What are the negative consequences of installing a switch between
>the main and essential buses?
>
>2. Is a contactor needed with the small aux battery?
>
>Joel Harding
What failures do you anticipate that you would be needing
the second battery to power the e-bus? If you do reasonable
preventative maintenance on the main battery AND do a load
analysis that shows your main battery will carry e-bus
loads for duration of fuel, I think I'd leave the second
battery for ignition only. In fact, with Z-11 and dual
17 a.h. batteries, you get 34 a.h. of cranking. You have
a less than two-year old battery in aux slot to carry
engine loads only. You've got a fresh battery in main
slot to carry e-bus loads only (I'd shut off one ignition
during alternator out operations).
>On Thursday, May 8, 2003, at 10:25 AM, Muzzy Norman E wrote:
>
> >
> >
> > I will run with a 40A alternator and an SD-8 for engine driven power
> > sources, and a pair of electronic ignition systems (no mags). The Z-13
> > diagram lays out the architecture for the SD-8 and L40 charging system
> > with
> > one battery. I could wire my ignition systems directly to the Battery
> > bus
> > as shown. It has been said several times that an electrically
> > dependent
> > ignition design really deserves two batteries. So, where do we go to
> > achieve this?
> >
> > We could adopt the architecture of Z-14 but use the SD-8 as a second
> > alternator. One of the challenges with this architecture is that it
> > requires a minimum of two contactors to power the busses where the
> > essential
> > items reside. The ignition systems would be located one each on the
> > battery
> > busses. I think that Z-14 makes sense with two big alternators, but
> > may not
> > be optimized for the SD-8.
> >
> > Or, we could add an additional battery to Z-13 using Figure Z-30. In
> > this
> > manner, we can run the essential bus philosophy, with an additional
> > battery
> > that could be isolated from the rest of the charging system. In order
> > to
> > supply the essential bus from the second battery, we need to modify
> > how the
> > essential bus is powered. As soon as you do that, it begins to smell
> > a lot
> > like an avionics bus, which can be powered from either Battery 1 or
> > Battery
> > 2. We can: A) leave it as is, with the diode to one of the main busses
> > and
> > alt feed from the same battery. B) use a 3 position switch as a
> > selector
> > between the two batteries (There's that avionics bus smell again...),
> > eliminate the diode (to prevent tying the batteries together during
> > starting
> > if the alt feed switch were on, or if one of the battery busses were
> > somehow
> > pulled close to ground).
> >
> > While we are considering how to tie this second battery in, we are also
> > being reminded that using lightweight washers instead of standard
> > washers
> > could save a few ounces on your airframe. And that adding weight is
> > even
> > worse than installing a split master switch! So, that little voice in
> > the
> > back of our head encourages us to install the Z-13 system with a single
> > battery and save the weight.
> >
> > My gut tells me to add a second battery to the Z-13 architecture,
> > using the
> > Z-30 technique. Tie the E-bus to the Battery bus that is associated
> > with
> > the SD-8.
> >
> > I suspect that I am not alone in debating these possibilities, and
> > would
> > like to here some discussion on what would be the appropriate manner to
> > handle feeding the E-bus.
If you have two engine driven power sources, then you don't
need two batteries. I'd run a Figure Z-13 system and run
both ignitions from the battery bus. Further, if you're really
tight on weight, you can down-size the battery to something on
the order of 10 a.h. if you don't mind the extra cost of the
smaller battery.
There are LOTS of different ways to hook things up that will
FUNCTION. What we should be trying to do is honor the wisdom
of a 13th century philosopher, William of Ockham who opined
"Plurality should not be assumed without necessity" . . . or
in more modern parlance, don't make it any more complex
than necessary. If you deduce some shortfall in the suggested
system cited above that drives a necessity for adding complexity
to the system, let's talk about it.
Bob . . .
________________________________________________________________________________
| From: | "David Carter" <dcarter(at)datarecall.net> |
| Subject: | Re: Documentation methods to print .pdf |
Thanks, Bob, for the patience to give an informative (long) reply to help us
get going on our documentation and design work.
Started modifying Z-13 for my RV-6 with John Deere PM alternator ("dynamo")
as the only alternator and two batteries, to power my Mazda rotary engine.
Making progress deleting the "std alternator, regulator, & mags", then
looking up "block names" in the Blocks window and the "insert blocks", by
name, into dwg (switches, dots, etc). Re-routing lines and having a great
time. I'll put the dwg out for peer review when done - hopefully in .pdf
format!
David Carter
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: AeroElectric-List: Documentation methods to print .pdf
>
>
> >
> >Bob,
> >
> >First topic of two: While jogging this morning, was trying to
digest/deduce
> >meaning of what you said yesterday about "fooling the computer into
thinking
> >that Adobe was a printer". Since I don't YET have Adobe Acrobat (only
have
> >Reader), I don't know the interface and menu choices and set-up on a
typical
> >Windows system, thus the following question(s):
> >
> > 1. If I have a .dwg or .dxf AutoCAD drawing I want to convert to
.pdf,
> >and IF/WHEN I have Adobe Acrobat, what are the "clicks"?
>
> you say "plot" or "print" and then when the print menu comes up,
> Acrobat Distiller will be one of your printer options in addition
> to any other printers you may have installed. Select Acrobat Distiller
> and then it will ask you things about paper size, landscape or
portrait,
> etc. Instead of spitting out image on hardware printer it asks you
> what you want to name the .pdf file and where you want it stored.
> If you've printed any application to a hardware printer, you can
> print to Adobe Acrobat just as easily.
>
>
> > -- For example, when Adobe Acrobat is first installed, is there
a
> >new "printer" icon installed called "Adobe" (along with my existing Canon
> >blk & white hooked to my computer and my wife's color printer hooked to
her
> >computer on other end of our LAN) which I print my file to so it gets
> >"printed" to the HD as a .pdf file (converted from whatever file type I
> >tried to print)?
>
> yup . ..
>
> > -- Likewise, if I have a .jpg file I want to convert to .pdf,
do I
> >just "print" it to Adobe to get the conversion?
>
> yup . . .
>
> > -- If that is the procedure, which folder does it "print" to?
> >(When I print to a real printer, there is no "save as" dialog box - will
> >there be in Adobe?)
> Adobe will ask you where to save it and what to name it . . .
>
> > 2. I looked at Kevin Horton's RV-8 Project website last night - I
> >nominate it as the GREATEST "builder documentation web site". He's
> >converted all his images to .pdf.
> > - I can even print his pdf documents/drawings from the website,
> >which I have never been able to do for any other pdf files being
displayed
> >on the web or in a browser (the "print" option has always been "grayed
out"
> >on other sites/files).
> > ?? Why is it that I can't usually print other people's pdf
files
> >being shown in a browser?
>
>
> Make sure you have the latest freebe version of Acrobat
> Reader . . although if you're going to install Acrobat
> then you'll get the latest reading capability with it. Uninstall
> older versions of Reader before you install Acrobat.
>
> Also, you can eliminate lots of potential for download/display
> problems if you tell your browser to download and store a .pdf
> to a directory and open it with Reader or Acrobat AFTER download
> is complete. This technique fixes about 90% of my readers
> complaints about Adobe .pdf files.
>
>
> >Meanwhile, I'm going to ebay and shopping for Adobe Acrobat (is that what
I
> >want/need?)
>
> That would sure be my choice. I've used it here now for about
> 5 years. Except for occasional hassles with specific browser/reader
> problems, it's been the most convenient and trouble free document
> generator for publication. Get the latest version you can . . .
> sometimes it's more economical to buy a new, unregistered copy
> in an older version and then get the update from Adobe. That's
> how I got my first Acrobat running . . . I think I did the whole
> thing for under $150. Also consider taking an engineering student
> to lunch and then dropping by the university bookstore after
> lunch so he/she can buy you a latest/greatest version at the
> university bookstore . . . these are QUITE reasonable too. They
> say "for academic use only" to which I reply, "I don't know how
> to use this and therefore I AM in the learning mode . . ."
>
> >Second topic: Plotting data with a CAD program (as opposed to plotting
in
> >Excel).
> > I tried creating a data chart once on Intellicad and could not get
the
> >desired results (I was very new to the system at that time). What are
the
> >basic steps in Autocad for creating a chart, with X & Y axis labeling and
> >"units" tick marks or graph paper lines, and plotting the data?
>
> Hmmm . . . this is pretty tall order for a two paragraph tutorial.
> When you get ready to study AutoCAD, find a file called acad.pgp
> Use a generic text editor like notepad.exe to cut and paste the
> following list into the file . . . erase all existing similar looking
> equivalents . . .
>
>
> AR, *ARRAY
> B, *BLOCK
> BR, *BREAK
> CI, *CIRCLE
> CC, *COPYCLIP
> CE, *COPYEMBED
> CH, *CHAMFER
> C, *CHANGE
> CO, *COPY
> E, *ERASE
> ED, *DDEDIT
> F, *FILLET
> H, *HATCH
> IN, *INSERT
> L, *LINE
> LA, *LAYER
> LC, *LTSCALE
> LT, *LINETYPE
> M, *MOVE
> MI, *MIRROR
> O, *OSNAP
> OF, *OFFSET
> PE, *PEDIT
> PG, *POLYGON
> PL, *PLINE
> Q, *EXIT
> R, *REDRAW
> RG, *REGEN
> RO, *ROTATE
> S, *STRETCH
> SC, *SCALE
> T, *TRIM
> TX, *TEXT
> U, *UNDO
> V, *VIEW
> WB, *WBLOCK
> XP *EXPLODE
> XT, *EXTEND
> Z, *ZOOM
>
> This is a list of 1 and 2-letter overlays for the
> fully spelled out plain English command that AutoCAD
> will understand. There are about 40 commands here.
> AutoCAD understand virtually hundreds and hundreds
> of commands . . . however, this is my personal .pgp
> file that represents the commands I use about 99% of the
> time. Therefore, this same list is a good study guide.
> Go down the right hand column of AutoCAD commands in this
> list and look them up in any study guides you may acquire.
> If you learn nothing but these commands (plus a few
> rudimentary houskeeping commands like "open" and "save")
> you'll be getting a handle on a suite of commands that
> does about everything I do with AutoCAD . . .
>
> I ignore the pull-downs and learned how to type with
> the right hand and steer the mouse with the left hand.
> I found it much easier to learn and faster to use
> than fiddle with those windows-like pulldowns.
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | "William Bernard" <billbernard(at)worldnet.att.net> |
| Subject: | Tach P-lead feed |
Neil, I ran my tach from the P-lead by wiring the tach through a SPST On-On switch.
This way, only one mag was used at a time and the choice was up to the pilot.
I've also seen this done using a switch with monentary contact for one pole,
but this makes a mag check a 3 handed operation.
Hope this helps.
Bill
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Whelen strobe current draw |
>
> > So, if we assume that the strobe outlets produce a
> > flash once every 860 milliseconds, then Outlets 3 42
>
> > watt/seconds divided by .86 seconds is 48 watts, or
> > 4 amps in a 12 volt system. This 4 amp "event" is
> > alternating with Outlet 1. Therefore, the power
> > pack is drawing 4 amps continuously, am I right?
>
>I'm no expert on this, but keep in mind that for the
>CF (Comet Flash) power supplies, everytime they
>"flash", they actually produce four flashes in very
>rapid succession. If the sum total of the four
>flashes is 42 joules, then your calculations might be
>correct. But if each one of the four flashes is 42
>joules, then you will be off by a factor of four.
Intuitively, one can assume that it's 44 Joules total.
I've built strobes for photography in years past that
called for energy levels of 10 to 200 Joules per
flash. Some tubes rated at 20 Joules are good for
about 1 flash per second lest they get REALLY hot
and break. The 200 Joule tubes had flash paths approaching
6" long and could only be flashed at full power about
once every 3 or 4 seconds . . . I've burned the
bejabbers out of a finger or two learning about
the inefficiency of flash tubes . . . for every
watt you put into them, you don't get but a few
hundred milliwatts of light . . . the rest comes
off as heat. Unless the CF system has really
beefy flash tubes, it's unlikely that you're
going to push 164 watt-seconds of snort into
them every flash cycle.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Documentation methods to print .pdf |
>
>
>Thanks, Bob, for the patience to give an informative (long) reply to help us
>get going on our documentation and design work.
>
>Started modifying Z-13 for my RV-6 with John Deere PM alternator ("dynamo")
>as the only alternator and two batteries, to power my Mazda rotary engine.
>
>Making progress deleting the "std alternator, regulator, & mags", then
>looking up "block names" in the Blocks window and the "insert blocks", by
>name, into dwg (switches, dots, etc). Re-routing lines and having a great
>time. I'll put the dwg out for peer review when done - hopefully in .pdf
>format!
>David Carter
Publish in both .pdf and .dwg if you want input from the
community. This lets users of capable drafting programs
open, edit, highlight, etc on the original for return to
you. .pdf is fine for simple sharing but in the development
phase, you'll get higher quality feedback from folks who
can work with the original.
While we're on this topic: Somebody published a link to
a builder site last week where a rather detailed power
distribution diagram which I've posted at:
http://216.55.140.222/temp/RV-9_Electrical.pdf
Without getting into specifics on the architecture,
permit me to point out the value in making drawings
for your project as page-per-system documents. The
power distribution diagram is best limited to defining
architecture . . . how the system functions. The
existence of circuit protection, a switch and a wire
gage coming off the main bus with an arrowhead pointing
to "Landing Light P.22" is sufficient to convey understanding
as to the total number of features in the system.
The page-per-system technique also lets you avoid
dense groupings of long parallel wires that migrate
across 50% of the drawing. The wiring diagram for
a Mooney is a sheet of paper about 3' wide and
8' long . . . it's one of the most user unfriendly
documents I've ever seen.
It's much easier to do 20 pages for a system
that to do one . . . trust me. Been there, done
that and won't do it again.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Z-13 and Dual Electronic Ignitions |
| From: | Joel Harding <cajole76(at)ispwest.com> |
On Friday, May 9, 2003, at 10:25 PM, Robert L. Nuckolls, III wrote:
>
>
>>
>>
>> Norm,
>> I have been contemplating many of the same ideas you just presented.
>> I
>> started out with Z-11 and added dual electronic ignitions. Then I
>> took
>> the Lightspeed recommendation to install a small 4.5 A H aux battery
>> as
>> a backup for one of the ignitions, and started thinking about using it
>> as a second power source for the essential bus. But then, like you I
>> began thinking why not install a disconnect between the main and
>> essential bus and use it as like an avionics bus since most of the
>> same
>> items would be on both.
>> The questions I have are:
>> 1. What are the negative consequences of installing a switch between
>> the main and essential buses?
>>
>> 2. Is a contactor needed with the small aux battery?
>>
>> Joel Harding
>
> What failures do you anticipate that you would be needing
> the second battery to power the e-bus? If you do reasonable
> preventative maintenance on the main battery AND do a load
> analysis that shows your main battery will carry e-bus
> loads for duration of fuel, I think I'd leave the second
> battery for ignition only. In fact, with Z-11 and dual
> 17 a.h. batteries, you get 34 a.h. of cranking. You have
> a less than two-year old battery in aux slot to carry
> engine loads only. You've got a fresh battery in main
> slot to carry e-bus loads only (I'd shut off one ignition
> during alternator out operations).
>
Bob,
The main incentive I had for going down this path was finding a simpler
method of incorporating the dreaded avionics bus into your essential
bus architecture. I know this is a major point of contention for you,
but I find myself dealing with the reality of a manufacturers
recommendation to provide protection for certain components, and I'm
too far into the stream to change horses. More important to me than
the failure modes was finding a way to simplify by combining the
avionics bus and the essential bus by isolating the main and essential
busses during starting. The aux bus backup was a lower priority
consideration to allow me to have some of these sensitive instruments
powered up during start without exposure to the brownout situation you
have discussed, and secondarily to provide a second power source for my
electronic flight instruments. I know this kind of talk probably makes
you crazy, but in my never ending quest to expose my ignorance of
electronics, I was compelled to present it to you.
I would appreciate your consideration of this idea.
Joel Harding
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: "Charred" Fast-On termnials |
Hi Bob,
After six years and 800 hours I am re-doing the panel in my RV-6. Upon
disassembly, I found that the fast-on terminals at my strobe switch
Were somewhat charred looking. All of the other fast-on terminals looked
like new. To my knowledge, the strobe (or wiring) never failed during the
800 hours of service. The strobes (Wheelen Comet Flash) were on for every
one of those 800 hours.
I am going to mail you the charred terminals. When you get the terminals,
I would appreciate your comments by e-mail.
Hmmm . . . yes, I would like to see them.
Thanks for taking the time to bring this
to my attention.
Mark,
I've inspected your sample terminals, photographed them
and posted the photo at:
http://216.55.140.222/temp/NonPIDGFastOn.jpg
I'm also sharing this note with the AeroElectric-List.
The plastic used on these terminals has lost its "plastic".
The material has become quite brittle. Have any other terminals
on your switch panel shown discoloration? You might
try the "squeeze" test on the insulation grip on other
terminals to see if they're still flexible.
You can see striations in the coloring where the plastic
is a darker brown in a pattern that matches tooling
marks on the terminal itself. What we see here is suggestive
of a chemical change to the plastic aggravated by heating.
Microscopic examination shows some transfer of plastic
to the terminal surface.
Check the remaining terminals on the panel for
evidence of lost tension at the insulation grips. These
are non-PIDG style terminals and at-risk for that
kind of behavior.
If this is the only problem-terminal of the bunch,
and given the good appearance of plating on the terminal's
metal parts, I don't think this joint was in imminent
danger of failure nor are other terminals marching
toward failure. The terminal you sent me WAS running warm.
I'm surprised that strobe system current was high enough
to single out this terminal for abuse.
You might be well served to replace the strobe switch
(it too is a source of heat if the normally open contact
is getting corroded) and the other terminals on the
switch.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| Subject: | Re:Ammeter needle fluctuation |
I have an RV-6 with an alternator and a Vans adjustable voltage regulator.
I've noticed the ammeter stabilized at higher Rpms (ie: climbout, runups,
etc.), but lower and medium RPMs the ammeter swings between + and - ranges.
It, also, seems to be rather erratic, in that it will be stable at lower
Rpms sometimes. My voltage reg. seems to be putting out 15V consistently
also....I'd appreciate any input you might have...Thanks Greg 319GH
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Z-13 and Dual Electronic Ignitions |
>
> >
>Bob,
>The main incentive I had for going down this path was finding a simpler
>method of incorporating the dreaded avionics bus into your essential
>bus architecture. I know this is a major point of contention for you,
>but I find myself dealing with the reality of a manufacturers
>recommendation to provide protection for certain components, and I'm
>too far into the stream to change horses. More important to me than
>the failure modes was finding a way to simplify by combining the
>avionics bus and the essential bus by isolating the main and essential
>busses during starting. The aux bus backup was a lower priority
>consideration to allow me to have some of these sensitive instruments
>powered up during start without exposure to the brownout situation you
>have discussed, and secondarily to provide a second power source for my
>electronic flight instruments. I know this kind of talk probably makes
>you crazy, but in my never ending quest to expose my ignorance of
>electronics, I was compelled to present it to you.
> I would appreciate your consideration of this idea.
A little disappointed perhaps but not crazy. And the goal
here is not to please me or any body else on the list.
I've often suggested that folks are better off with a system
they understand and are comfortable with than to be worrying
about something unique to their level of understanding.
Keep in mind that the vast majority of SE aircraft flying today
are wired not unlike the CessnaBeechPiperMooneys of decades
gone by . . . including OBAM aircraft. Airplanes wired
per the Z-drawings are rare in comparison with the total
fleet of aircraft.
When I ask people to justify their wish to modify any
of the systems we've published, it's not because I have
any notion of convincing them to "do it my way." My
query is aimed at acquiring insight as to some point
of engineering I may have overlooked. The Z-drawings
have evolved a lot over the last 10 years and I'd be
foolish to believe they should not evolve further.
My job is not to persuade you to do anything. My
job is to help you understand how the system works.
Your job is to craft a system that is not distracting
because of concerns or misunderstood operation. So
in answer to your questions:
You can certainly add a switch in series with normal
feedpath diode to service as an "avionics master"
You don't need to use a contactor for an aux battery
unless the battery is robust enough to aid in cranking
and/or it is your intent NOT to use it to assist the main
battery in cranking. Indeed, when the automatic aux
battery management concept was published in Sport Aviation
about 6 years ago, the aux battery was perhaps a 4-6 a.h.
device connect to the bus via a 30A power relay like our
S704-1.
May I suggest the following actions which may work
toward mitigating your concerns? Give me a list of
folks who have supplied you with equipment that they
claim is "sensitive" . . and let's at least ask them
to provide a justification for their assertions
based on physics.
I presume you followed the conversation
with Electronics International over the last two weeks.
It turns out that they haven't a clue as to why their
products should or should not be "protected".
While they claimed credit for full compliance under
TSO requirements that include DO-160 testing, they
didn't truly understand the significance of the tests
they paid money to accomplish. Nor did they understand
the significance of that testing with respect to their
customer's reasonable expectations.
In EVERY case I've looked at over the past 15 years,
not one company asking for an "avionics master switch"
was able to enlighten me with an explanation. In more than
half the cases, they admitted that there was no
justification and that the topic of avionics master
switch was part of the boiler-plate used to craft installation
manuals since the 60's and nobody has ever bothered to
review that requirement and take it out of the book.
I don't know if the outcome of such an exercise would influence
the way you configure your airplane and it doesn't matter.
Bottom line is that what ever goes into YOUR airplane
should minimize your worries as an owner and maintainer
of the airplane so that you can maximize your performance
as the pilot of that airplane.
Bob . . .
________________________________________________________________________________
| From: | "Terry Watson" <terry(at)tcwatson.com> |
Bob,
Have you had any progress (or tried) convincing Greg Richter at Blue
Mountain Avionics that their EFIS-1 doesn't need to be on an avionics bus?
Terry
RV-8A
Blue Mountain EFIS-1
________________________________________________________________________________
| From: | Mark Phillips <ripsteel(at)edge.net> |
| Subject: | Small Relay Diodes |
It it considered good practice to add diodes across the coils of small
relays such as would be used for flap controls or trim relays when using
stick switches? I am using a 3PDT relay for landing light/flasher
control that has a 100 ohm coil. Z-18 shows one, but they don't appear
on other drawings. If so, a 1N4001 or equiv. would work?
Advisable or not necessary?
Thanks
Mark Phillips
________________________________________________________________________________
| From: | "Eric M. Jones" <emjones(at)charter.net> |
I subscribed to the Marlin P. Jones Associates (no relation) e-mail special and
bought their TRMS RS232 Multimeter, the $89.95 Meter. All I gotta say is holy
cow! If you need a multimeter, appreciate and use this kind of technology, check
this one out.
http://www.mpja.com/productview.asp?product14521+TE $89.95 (TRMS and measures temps with supplied thermocouples)
http://www.mpja.com/productview.asp?product14311+TE $49.95 (standard but still incredibly impressive).
Caveat emptor, but this seems like an amazing deal to me!
Eric M. Jones
When trouble arises and things look bad, there is always one individual who
perceives a solution and is willing to take command. Very often, that individual
is crazy.
--Dave Barry
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Small Relay Diodes |
>
>It it considered good practice to add diodes across the coils of small
>relays such as would be used for flap controls or trim relays when using
>stick switches? I am using a 3PDT relay for landing light/flasher
>control that has a 100 ohm coil. Z-18 shows one, but they don't appear
>on other drawings. If so, a 1N4001 or equiv. would work?
>
>Advisable or not necessary?
>
>Thanks
>Mark Phillips
It almost never hurts. It's a good idea for larger loads
like contactors that store probably 10-50x more energy
than their little relay counsins.
First, keep in mind that energy in the "spike" that comes
off a relay or contactor coil is 99.9% used up in the
spreading contacts of the controlling switch. So adding
a diode to any coil is to increase the life of the switch.
The 100 mA or so relays don't represent much risk to a
switch but then, a 1N400x diode is pretty cheap and easy
to install . . . so why not?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>I subscribed to the Marlin P. Jones Associates (no relation) e-mail
>special and bought their TRMS RS232 Multimeter, the $89.95 Meter. All I
>gotta say is holy cow! If you need a multimeter, appreciate and use this
>kind of technology, check this one out.
>
>http://www.mpja.com/productview.asp?product14521+TE $89.95 (TRMS and
>measures temps with supplied thermocouples)
>
>http://www.mpja.com/productview.asp?product14311+TE $49.95 (standard
>but still incredibly impressive).
>Caveat emptor, but this seems like an amazing deal to me!
It used to be that to ask for better than 3% accuracy
in ordinary test tools was a stretch, nowadays 1% is
commonplace. I purchased my first new instrument the day
I got a job at Boeing (fall of 1961 . . . $86.00/wk).
It was shinny new Triplet Model 630 and I gave about $70
for it. This would have been a typical 3% instrument of
the era. According to the inflation calculator at
http://www.westegg.com/inflation/
. . . that $70 instrument would cost me $410.00 today
or working backwards, the $50 instrument Eric cited
would cost $8.60 in 1961 dollars. This is a really
neat business to be in. We can do more for less dollars
tomorrow. Now if government could be taught to operate
the same way . . .
As I recall . . . one could buy a C-172 for about
$15000 when I worked there. According to inflation
calculator, the airplane should sell for about $88,000
today and IT wouldn't even fly better than it did in
1961 . . . wonder where we went wrong.
Bob . . .
________________________________________________________________________________
| Subject: | Re: Z-13 and Dual Electronic Ignitions |
| From: | czechsix(at)juno.com |
Bob,
I'm a bit baffled on your reply that "if you have two engine driven power
sources, then you don't need two batteries". A couple months ago we had
a lively exchange where you were poo-pooing my questions about tying
electronic ignition leads directly to the battery to eliminate failure
points between the battery and the battery bus (something about swatting
gnats). Then when you realized I was talking about DUAL electronic
ignition, you said that I should have dual batteries. My plan up until
then had been to go with Z-13, single battery/dual alternator. But this
does mean that the single battery is a single point failure that will
result in engine failure if it's integrity is destroyed. Someone
recently had a case where their battery lead bolt broke clean off (wasn't
it a Powersonic RG battery?).
Anyway, I still don't know what to think....I've gotta believe that
complete battery failure with an RG is rare, but nevertheless I thought
maybe it would be better to go with dual batteries. The configuration
I've tentatively settled on is the one Klaus Savier recommends....single
alternator and single main battery, plus a very small standby battery
that is charged through a Schottky diode to isolate it from everything
else, and runs one of the ignition systems. This seemed to me to be the
lightest, simplest and cheapest setup that offered assurance of ignition
system redundancy. It doesn't have the convenience of running an SD-8 if
the main alternator quits, but since I'm running a B&C main alternator I
felt the odds of being stuck somewhere (albeit safely on the ground) away
from home with my alternator dead to be pretty low risk and probably
worth the compromise in the long run.
I was just amused at your statement on Z-13 because I thought that you
did not advocate this setup for dual electronic ignition?
--Mark Navratil
Cedar Rapids, Iowa
RV-8A N2D finishing...
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: Re: AeroElectric-List: Z-13 and Dual Electronic Ignitions
If you have two engine driven power sources, then you don't
need two batteries. I'd run a Figure Z-13 system and run
both ignitions from the battery bus. Further, if you're really
tight on weight, you can down-size the battery to something on
the order of 10 a.h. if you don't mind the extra cost of the
smaller battery.
There are LOTS of different ways to hook things up that will
FUNCTION. What we should be trying to do is honor the wisdom
of a 13th century philosopher, William of Ockham who opined
"Plurality should not be assumed without necessity" . . . or
in more modern parlance, don't make it any more complex
than necessary. If you deduce some shortfall in the suggested
system cited above that drives a necessity for adding complexity
to the system, let's talk about it.
Bob . . .
The best thing to hit the internet in years - Juno SpeedBand!
Surf the web up to FIVE TIMES FASTER!
________________________________________________________________________________
| From: | "David Carter" <dcarter(at)datarecall.net> |
| Subject: | Re: Z-13 and Dual Electronic Ignitions |
Mark Navratis (czechsix?),
I am the least qualified to even attempt a comment here, but that never
stops me from trying.
I, too, am in process of modifying Z-13 for my all electric Mazda rotary
engine. I, too, am concerned about a battery failure, and equally concerned
about battery contactor failure. (I don't have a great fear of the
probability of either, but believe there is enough anecdotal history to make
me design my system so either or both will be a "no sweat" situation (Bob's
"prime directive").
That is why I'm going to use a Permanent Magnet Alternator (John Deere 35,
55 or 85 amp) (the "alternate alternator is labeled "Dynamo" in Z-13 - this
is a PM alternator).
- PM alternators/dynamos operate with no need for a battery - ever.
-- So, if battery fails, PM Alternator continues to put out
regulated DC to the left hand (in Z-13) terminal of the battery contactor,
which is where the wire that feeds the Battery Bus connects, which means
that the battery can short, open, or melt and all run out a hole in the
bottom of the plane -- and the battery bus, essential bus, and all electric
engine will hum away on alternator power.
I'm going to run only a single alternator - the PM alternator. They are
supposed to be so reliable, and totally independent of the battery, that I
don't see why I'd want all the "risks" that come with a "battery dependent,
and battery contactor dependent std alternator.
I'm adding a second battery, so will have a "2 battery, single PM
alternator" system.
- Haven't decided if I want to use 2 regular size batteries (may need
that for "battery-only electrical endurace" close to equal to "fuel
endurance"): 1) IF my electrically fed and fired engine current draw is
not too great (don't have all the current draw info yet for 2 ignition
coils, efi pump (1 on at a time except for T.O. & land), and Tracy Crook's
EC-2 ignition-injection controller (engine computer), THEN may go with a
small expensive light weight battery isolated just for the engine.
2) If need the extra juice, and if need the extra
amp capacity for cranking engine, will go the easy, heavier, cheaper way and
go with 2 17AH batteries (this is what I feel will be my choice - makes
annual battery replacement and rotation simple, lower cost, better
reliability, and I don't care about the difference in weight - my Mazda
rotary already saves me about 20#.)
Does this help any, in trying to sort things out? If not, please help me
understand more & better.
David Carter
----- Original Message -----
From: <czechsix(at)juno.com>
Subject: Re: AeroElectric-List: Z-13 and Dual Electronic Ignitions
>
> Bob,
>
> I'm a bit baffled on your reply that "if you have two engine driven power
> sources, then you don't need two batteries". A couple months ago we had
> a lively exchange where you were poo-pooing my questions about tying
> electronic ignition leads directly to the battery to eliminate failure
> points between the battery and the battery bus (something about swatting
> gnats). Then when you realized I was talking about DUAL electronic
> ignition, you said that I should have dual batteries. My plan up until
> then had been to go with Z-13, single battery/dual alternator. But this
> does mean that the single battery is a single point failure that will
> result in engine failure if it's integrity is destroyed. Someone
> recently had a case where their battery lead bolt broke clean off (wasn't
> it a Powersonic RG battery?).
>
> Anyway, I still don't know what to think....I've gotta believe that
> complete battery failure with an RG is rare, but nevertheless I thought
> maybe it would be better to go with dual batteries. The configuration
> I've tentatively settled on is the one Klaus Savier recommends....single
> alternator and single main battery, plus a very small standby battery
> that is charged through a Schottky diode to isolate it from everything
> else, and runs one of the ignition systems. This seemed to me to be the
> lightest, simplest and cheapest setup that offered assurance of ignition
> system redundancy. It doesn't have the convenience of running an SD-8 if
> the main alternator quits, but since I'm running a B&C main alternator I
> felt the odds of being stuck somewhere (albeit safely on the ground) away
> from home with my alternator dead to be pretty low risk and probably
> worth the compromise in the long run.
>
> I was just amused at your statement on Z-13 because I thought that you
> did not advocate this setup for dual electronic ignition?
>
> --Mark Navratil
> Cedar Rapids, Iowa
> RV-8A N2D finishing...
>
> From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
> Subject: Re: AeroElectric-List: Z-13 and Dual Electronic Ignitions
>
>
> If you have two engine driven power sources, then you don't
> need two batteries. I'd run a Figure Z-13 system and run
> both ignitions from the battery bus. Further, if you're really
> tight on weight, you can down-size the battery to something on
> the order of 10 a.h. if you don't mind the extra cost of the
> smaller battery.
>
> There are LOTS of different ways to hook things up that will
> FUNCTION. What we should be trying to do is honor the wisdom
> of a 13th century philosopher, William of Ockham who opined
> "Plurality should not be assumed without necessity" . . . or
> in more modern parlance, don't make it any more complex
> than necessary. If you deduce some shortfall in the suggested
> system cited above that drives a necessity for adding complexity
> to the system, let's talk about it.
>
> Bob . . .
>
>
> The best thing to hit the internet in years - Juno SpeedBand!
> Surf the web up to FIVE TIMES FASTER!
>
>
________________________________________________________________________________
| Subject: | RE: Magneto buzz box circuit |
| From: | "David" <David(at)ChalmersFamily.com> |
I want to put together a circuit to time my magnetos. Seems like the
mags appear as a capacitor, coil and switch in parallel. I need a
circuit to tell when the switch is closed. I did this previously by
feeding the output of a 555 oscillator into the points and looking for
the amplitude change on a scope but I'd like to build something that is
simpler to use - i.e has an LED or buzzer. Anyone got a schematic for a
simple buzz box?
Thanks
Dave Chalmers
________________________________________________________________________________
| From: | "Wolfgang Trinks" <Wolfgang.Trinks(at)flugbereitschaft.com> |
Hello Bob,
I am a professional pilot flying a Citation II in Karlsruhe-Baden/Germany(
with an engineering background) a former canadian F-18 Airbase. At the time
I am conducting restoration of a Stampe SV4 Biplane(all wood) for my private
use. Fourtunately we have our own JAR 145 maintenance facility, so I have
good support for dealing with the feds( its a certified aircraft in
Germany).
For the engine I am in progress of a STC for the LOM engine because I think
there is no future in the old Renault.
As I have to put an electric system into the plane and I have never done
this before from scratch your experiance written down will be a lot of help.
I am now starting the planing of the system and one of my first
considerations is the OVP-System given the 28Volt Magnetron Generator
supplied to the engine. ( I am aware that B&C has introduced a alternator
system for the engine, but unfortunately its not certified in Germany).
One fact that is growing of more and more importance during my project is to
be very carefull putting up more and more weight to an airplane that was
very basic in the first place. Also the space on my firewall is very
limited.
So looking at your drawing Z-18 raises a question of what I wood be
interested in your opinion:
Would it be ok related to the failure scenarios of a mechanical regulator to
only use the GENERATOR FIELD DISCONNECT RELAY to cut the field in an
OVP-event and to rely on the reverse current cuttoff relay consisted in the
regulator to disconnect the D+ line from the B+ line due to the resulting
breakdown of the generator output?
Do you have experience with this LUN regulator?
I have studied the little scematic in the cap and came to the opinion that
it is a 3 point type (cutout, voltage and current) where 2 contacts( cutout
and current) are located on one coil core.
I have to admit that I do not fully understand the functionality of the PR
pin. It seems to me to be a potential paralleling in/output for a
2-Generator system.
Nevertheless I have meassured that it is normally open and if the cutout
relay is connecting the generator voltage shows up there after passing a
coil on the voltage relay.
If one knew the effects on the voltage regulation( so to avoid influance
there) it would be a positive possible indication for generator operation
because it shows the state of the cutout relay.
Best Regards
Wolfgang Trinks, StampeSV4C,D-EBHR, EDSB
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Z-13 and Dual Electronic Ignitions |
>
>
>Mark Navratis (czechsix?),
>
>I am the least qualified to even attempt a comment here, but that never
>stops me from trying.
>
>I, too, am in process of modifying Z-13 for my all electric Mazda rotary
>engine.
Why Figure Z-13 if you have only one alternator drive?
> I, too, am concerned about a battery failure, and equally concerned
>about battery contactor failure. (I don't have a great fear of the
>probability of either, but believe there is enough anecdotal history to make
>me design my system so either or both will be a "no sweat" situation (Bob's
>"prime directive").
Which is why we consider the option of adding a second battery . . .
>That is why I'm going to use a Permanent Magnet Alternator (John Deere 35,
>55 or 85 amp) (the "alternate alternator is labeled "Dynamo" in Z-13 - this
>is a PM alternator).
> - PM alternators/dynamos operate with no need for a battery - ever.
> -- So, if battery fails, PM Alternator continues to put out
>regulated DC to the left hand (in Z-13) terminal of the battery contactor,
>which is where the wire that feeds the Battery Bus connects, which means
>that the battery can short, open, or melt and all run out a hole in the
>bottom of the plane -- and the battery bus, essential bus, and all electric
>engine will hum away on alternator power.
Not necessarily so. Some regulators (including the B&C regulator
for the SD-8/200G series alternators) won't allow the alternator
to come on line without a battery. I'm not certain of the rational
for this design but I would guess that it's a recognition of the
single phase, pm alternator's really ratty output. There are some
more modern, 3-phase designs available now. I have no personal
experience with them. But don't go on faith that because the
alternator has no need of field excitation that it will automatically
be available and useable sans battery. This takes some degree
of testing and/or research on the alternator/regulator's characteristics
as a system.
>I'm going to run only a single alternator - the PM alternator. They are
>supposed to be so reliable, and totally independent of the battery, that I
>don't see why I'd want all the "risks" that come with a "battery dependent,
>and battery contactor dependent std alternator.
If you have only one alternator drive, then I'd stay with the modern
fielded alternator . . . especially an ND. In over 10 years
of supplying this alternator to the OBAM community, B&C
has yet to have a gross failure of an alternator
due to wearout. All failures to date were installer/
operator induced. There has been a sprinkling of regulator
failures for a variety of reasons . . . there's probably
a similar risk of failure for a pm regulator . . . perhaps
even more risk. PM regulators have to be designed to CARRY
load currents. The parts are more highly stressed and need
heat sinks. A regulator for wound field alternators carries
only field current . . . 3A max, less than 1A in cruising
flight. MUCH less stress.
>I'm adding a second battery, so will have a "2 battery, single PM
>alternator" system.
So what you might consider is Z-11 with a Z-30 second
battery. This is the system I proposed in the aux battery
management module article in SA some years ago. A pair
of identical batteries with the yearly swap around of
new->main and main->aux combined with the demonstrated
reliability of an ND alternator is pretty hard to beat for cost
effectiveness and efficiency (the ND will give you more snort
with smaller installed volume and weight).
> - Haven't decided if I want to use 2 regular size batteries (may need
>that for "battery-only electrical endurace" close to equal to "fuel
>endurance"): 1) IF my electrically fed and fired engine current draw is
>not too great (don't have all the current draw info yet for 2 ignition
>coils, efi pump (1 on at a time except for T.O. & land), and Tracy Crook's
>EC-2 ignition-injection controller (engine computer), THEN may go with a
>small expensive light weight battery isolated just for the engine.
Which gives you dissimilar batteries to monitor and maintain
with no convenience of calendar based swap-around. Are you
planning to periodically capacity check your batteries?
> 2) If need the extra juice, and if need the extra
>amp capacity for cranking engine, will go the easy, heavier, cheaper way and
>go with 2 17AH batteries (this is what I feel will be my choice - makes
>annual battery replacement and rotation simple, lower cost, better
>reliability, and I don't care about the difference in weight - my Mazda
>rotary already saves me about 20#.)
Hear, hear . . .
> > Bob,
> >
> > I'm a bit baffled on your reply that "if you have two engine driven power
> > sources, then you don't need two batteries". A couple months ago we had
> > a lively exchange where you were poo-pooing my questions about tying
> > electronic ignition leads directly to the battery to eliminate failure
> > points between the battery and the battery bus (something about swatting
> > gnats). Then when you realized I was talking about DUAL electronic
> > ignition, you said that I should have dual batteries. My plan up until
> > then had been to go with Z-13, single battery/dual alternator. But this
> > does mean that the single battery is a single point failure that will
> > result in engine failure if it's integrity is destroyed. Someone
> > recently had a case where their battery lead bolt broke clean off (wasn't
> > it a Powersonic RG battery?).
Yeah . . . probably got my tongue tangled around my eye-teeth
and couldn't see what I was saying. If you have an electrically
dependent airplane, adding a second battery is the most effective
first-step to improved reliability.
In retrospect, I'm wondering if I was thinking about the engines
that run a single ignition or fuel delivery system wherein there
are lots of single points of failure. In these cases, our comfort
factor can go up only by improving the reliability of the single
system with judicious parts selection, operating at reduced stress and
more tightly controlled attention to details of assembly. In
these airplanes, I'm wondering if two batteries adds that much
overall system reliability . . .
The 4-pound, SD-8 installation is a very attractive alternative
to a second battery . . and depending on how you use your airplane,
may be an acceptable step-down from dual-battery reliability in
trade for unlimited endurance with a lot less weight and lower
cost of ownership.
We launch into detailed fault tree and reliability analysis
tasks when these kinds of discussions come up on the certified
iron. Problem is that MTBF numbers used for most hardware
are derived analytically. By the time you get a few dozen
assumptions piled on top of each other in a very complex
system, the overall analysis is pretty suspect. The FAA
realizes this so they put a 10x factor on requirements.
One failure per million flight hours is their idea of
failure proof. I personally don't have much confidence in
these exercises and don't believe they give the customer
good value. It's better to design for failure tolerance
in confidence than to design for failure proof with
fondest wishes.
> >
> > Anyway, I still don't know what to think....I've gotta believe that
> > complete battery failure with an RG is rare, but nevertheless I thought
> > maybe it would be better to go with dual batteries. The configuration
> > I've tentatively settled on is the one Klaus Savier recommends....single
> > alternator and single main battery, plus a very small standby battery
> > that is charged through a Schottky diode to isolate it from everything
> > else, and runs one of the ignition systems. This seemed to me to be the
> > lightest, simplest and cheapest setup that offered assurance of ignition
> > system redundancy. It doesn't have the convenience of running an SD-8 if
> > the main alternator quits, but since I'm running a B&C main alternator I
> > felt the odds of being stuck somewhere (albeit safely on the ground) away
> > from home with my alternator dead to be pretty low risk and probably
> > worth the compromise in the long run.
It stands to reason that lightly stressed parts are going to
be more reliable operating up to and including the limits
of capacity than highly stressed parts. This is why we design
wing and prop attach hardware with lots of headroom. Alternators
and batteries are routinely operated at the limits of their capability
(and from experience we know that the do fail and wear out -
an airplane may see dozens of batteries and several alternators
over its lifetime of operation on one set of wings).
This is why we adopt the philosophy of designing for failure
tolerance in electrical systems (you gotta install
a ballistic parachute to design for failure tolerance in wings).
> >
> > I was just amused at your statement on Z-13 because I thought that you
> > did not advocate this setup for dual electronic ignition?
Correct. Sometimes after a day of brain-wrestling with
these things all day at RAC, my thought train gets
derailed . . .
One of these days, it would interesting to do a formal fault tree
and reliability analysis of the various system options for publication
but that takes a lot of time and data (another reason
certified ships cost so much). Soooo . . . in the mean time,
I'll have to rely on you guys to throw down the flag when you
detect a derail . . .
Bob . . .
________________________________________________________________________________
| From: | "Rhett Westerman" <Rhettwesterman(at)cox.net> |
Rick,
Not sure if you have an OVM in there or not. I had the same trouble and a
new OVM fixed it.
best,
Rhett
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com]On Behalf Of Rick
Caldwell
Subject: AeroElectric-List: Alt Field Trip
Hello All,
Anyone have experience in alternator circuit failures that could narrow down
my search?
I have a 40A B&C alternator with the LR3B-14v for control. My 5A field CB
pops. However, after a minute or so, I can reset it and it stays in, most
of the time. I have the Aeroelectric loadmeter and the load on resetting is
high but settles down to the normal 10% load after a minute or so. Adding
or cutting off loads does not seem to influence the tripping. No blown
fuses on any of the other circuits. I just installed a new Concorde 25RG-XC
battery thinking that was the problem. It wasn't. Tripped on take-off last
night. I will now start looking for intermittent shorts tomorrow. I sure
don't want to find that the LR3B is bad. I've flown 3.5 yrs with no alt.
problems until now.
Rick Caldwell
RV-6
________________________________________________________________________________
| From: | "Paul McAllister" <paul.mcallister(at)qia.net> |
| Subject: | Source for Pins & Extraction tools |
Hi all,
I am approaching the stage where I will be wiring up my UPS GX60 Nav/Com & SL 70
transponder. The units come supplied with 37 pin D style connectors and I am
seeking some advice.
Where can I purchase a suitable crimping tool, insertion/extraction tool and some
pins & sockets. I would be interested to know what size wire do people typically
use in these pins to ensure a good crimp
Thanks, Paul
http://europa363.versadev.com/
________________________________________________________________________________
| Subject: | WX900 Stormscope |
Gang,
Anybody have a pinout and/or installation manual for a WX-900
Stormscope?
Dan Horton
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Source for Pins & Extraction tools |
>
>
>Hi all,
>
>I am approaching the stage where I will be wiring up my UPS GX60 Nav/Com &
>SL 70 transponder. The units come supplied with 37 pin D style connectors
>and I am seeking some advice.
>
>Where can I purchase a suitable crimping tool, insertion/extraction tool
>and some pins & sockets.
See:
http://www.aeroelectric.com/Catalog/tools/tools.html#rct-3
http://www.aeroelectric.com/Catalog/tools/tools.html#dse-1
http://www.aeroelectric.com/Catalog/connect/connect.html#S604
http://www.aeroelectric.com/Catalog/BCcatalog.html
> I would be interested to know what size wire do people typically use in
> these pins to ensure a good crimp
24-20 AWG wire works well in these pins. 20AWG for
power/ground and 22AWG for everything else is
good . . .
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| Subject: | Source for Pins & Extraction tools |
| From: | "Don Honabach" <don(at)pcperfect.com> |
Hi Everyone,
I noticed that when crimping the machined pins for the D style
connectors that the insulation on the wire usually ends up exposing
about a 1mm of wire despite my best attempts to keep the insulation
right next to the pin during the crimp.
Obviously 1mm of wire showing isn't going to be a problem, but it bugs
me. Is this normal for these type of pins/connectors? Has anyone been
able to keep a 0 tolerance on the wire shown at the back end of the pin?
I'm just trying to get a feeling of whether I need to practice and just
come up with a better technique, or if I'm fighting a losing battle.
Thanks!
Don Honabach
Tempe, AZ - Zodiac 601HDS
P.S. Getting ready to start my electrical installation and can't wait.
A little burned out on the mark, drill, de-bur, corrision protect, and
rivet it game.
-----Original Message-----
From: Robert L. Nuckolls, III [mailto:bob.nuckolls(at)cox.net]
Subject: Re: AeroElectric-List: Source for Pins & Extraction tools
-->
>
>
>Hi all,
>
>I am approaching the stage where I will be wiring up my UPS GX60
>Nav/Com &
>SL 70 transponder. The units come supplied with 37 pin D style
connectors
>and I am seeking some advice.
>
>Where can I purchase a suitable crimping tool, insertion/extraction
>tool
>and some pins & sockets.
See:
http://www.aeroelectric.com/Catalog/tools/tools.html#rct-3
http://www.aeroelectric.com/Catalog/tools/tools.html#dse-1
http://www.aeroelectric.com/Catalog/connect/connect.html#S604
http://www.aeroelectric.com/Catalog/BCcatalog.html
> I would be interested to know what size wire do people typically use
> in
> these pins to ensure a good crimp
24-20 AWG wire works well in these pins. 20AWG for
power/ground and 22AWG for everything else is
good . . .
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
direct advertising on the Matronics Forums.
________________________________________________________________________________
| From: | "Gary Casey" <glcasey(at)adelphia.net> |
<>
This is probably heresy, but I use a simple ohmmeter. It has to be a fairly
good one to detect the difference between the resistance of the coil (less
than 1 ohm) and the shorted points. I ONLY connect the ohmmeter when I am
right the correct timing value and then bump the crank very slowly. Do it
with any speed and there will occur a voltage spike when the points open
that could damage the ohmmeter. The easy way is to back the crank up and
turn it forward, listening for the impulse coupling click at about TDC.
Then back the crank up to just before 25 BTC and very slowly go forward. A
little time consuming, but if you only do it once in a great while it works.
Just don't send me a bill for your blown-up ohmmeter.
Gary Casey
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
| Subject: | Z-13 and Dual Electronic Ignitions |
Bob,
As I have mentioned before, there is ONE case where an avionics master
is really needed. It's to protect the Chelton EFIS computer during its
boot-up stage when its opening and closing config files. If it reboots
while it has one of these files open, corruption of this file is a
possibility, rendering the unit useless.
Now, I won't go as far to say that this behavior is acceptable and
correct, but the fact is it does exist (whereas ALL of the other calls
for an avionics master are baseless, as you say).
I think this area is one that might need to be addressed in the future
as more things go electronic and computerized. Hopefully, the
manufacturers will make them immune to this, but, if not, it will need
to be addressed by a Z drawing.
My solution and suggestion to a solution is to create an avionics buss
that also doubles as an essential (or endurance) buss, that is fed by an
alternate feed switch. I also suggest this architecture to people that
are uncomfortable sleeping at night without their avionics behind a
master, whether it's for unfounded passed on blurb, or if its just for
convenience. This architecture adds one switch (av master) to a typical
Z14 with ess buss, and really provides the best of both worlds.
Shannon
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Robert L. Nuckolls, III
Subject: Re: AeroElectric-List: Z-13 and Dual Electronic Ignitions
>
> >
>Bob,
>The main incentive I had for going down this path was finding a simpler
>method of incorporating the dreaded avionics bus into your essential
>bus architecture. I know this is a major point of contention for you,
>but I find myself dealing with the reality of a manufacturers
>recommendation to provide protection for certain components, and I'm
>too far into the stream to change horses. More important to me than
>the failure modes was finding a way to simplify by combining the
>avionics bus and the essential bus by isolating the main and essential
>busses during starting. The aux bus backup was a lower priority
>consideration to allow me to have some of these sensitive instruments
>powered up during start without exposure to the brownout situation you
>have discussed, and secondarily to provide a second power source for my
>electronic flight instruments. I know this kind of talk probably makes
>you crazy, but in my never ending quest to expose my ignorance of
>electronics, I was compelled to present it to you.
> I would appreciate your consideration of this idea.
A little disappointed perhaps but not crazy. And the goal
here is not to please me or any body else on the list.
I've often suggested that folks are better off with a system
they understand and are comfortable with than to be worrying
about something unique to their level of understanding.
Keep in mind that the vast majority of SE aircraft flying today
are wired not unlike the CessnaBeechPiperMooneys of decades
gone by . . . including OBAM aircraft. Airplanes wired
per the Z-drawings are rare in comparison with the total
fleet of aircraft.
When I ask people to justify their wish to modify any
of the systems we've published, it's not because I have
any notion of convincing them to "do it my way." My
query is aimed at acquiring insight as to some point
of engineering I may have overlooked. The Z-drawings
have evolved a lot over the last 10 years and I'd be
foolish to believe they should not evolve further.
My job is not to persuade you to do anything. My
job is to help you understand how the system works.
Your job is to craft a system that is not distracting
because of concerns or misunderstood operation. So
in answer to your questions:
You can certainly add a switch in series with normal
feedpath diode to service as an "avionics master"
You don't need to use a contactor for an aux battery
unless the battery is robust enough to aid in cranking
and/or it is your intent NOT to use it to assist the main
battery in cranking. Indeed, when the automatic aux
battery management concept was published in Sport Aviation
about 6 years ago, the aux battery was perhaps a 4-6 a.h.
device connect to the bus via a 30A power relay like our
S704-1.
May I suggest the following actions which may work
toward mitigating your concerns? Give me a list of
folks who have supplied you with equipment that they
claim is "sensitive" . . and let's at least ask them
to provide a justification for their assertions
based on physics.
I presume you followed the conversation
with Electronics International over the last two weeks.
It turns out that they haven't a clue as to why their
products should or should not be "protected".
While they claimed credit for full compliance under
TSO requirements that include DO-160 testing, they
didn't truly understand the significance of the tests
they paid money to accomplish. Nor did they understand
the significance of that testing with respect to their
customer's reasonable expectations.
In EVERY case I've looked at over the past 15 years,
not one company asking for an "avionics master switch"
was able to enlighten me with an explanation. In more than
half the cases, they admitted that there was no
justification and that the topic of avionics master
switch was part of the boiler-plate used to craft installation
manuals since the 60's and nobody has ever bothered to
review that requirement and take it out of the book.
I don't know if the outcome of such an exercise would influence
the way you configure your airplane and it doesn't matter.
Bottom line is that what ever goes into YOUR airplane
should minimize your worries as an owner and maintainer
of the airplane so that you can maximize your performance
as the pilot of that airplane.
Bob . . .
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
It is actually possible that Greg's system needs protected, just like my
Chelton, due to it opening and closing files during bootup. I think
Greg's is more PC based so it might be better at handling this, but the
Chelton isn't as forgiving.
These computers are really the ONLY thing that even has a chance of
needing the AV Master, as Bob has shown many times.
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Terry
Watson
Subject: AeroElectric-List: Avionics bus
Bob,
Have you had any progress (or tried) convincing Greg Richter at Blue
Mountain Avionics that their EFIS-1 doesn't need to be on an avionics
bus?
Terry
RV-8A
Blue Mountain EFIS-1
________________________________________________________________________________
| From: | "Ralph E. Capen" <recapen(at)earthlink.net> |
| Subject: | Supporting the other ends of our gyros |
Fellow listers,
What are you doing (have you done) to support the forward (back) ends of your long
gyros?
A couple of mine will go through the next forward bulkhead so I can probably rivet
on a piece of angle and clamp the gyro to that. One (AI) is too short but
is right on top of another (HSI) that goes through the next forward bulkhead
- I was thinking of making up a spacer to put those two together and clamp them
together using the support on the one that goes all the way through to hold
both. Another of mine (S-Tec30 TC/AP) is also too short and is not close enough
to another one to "lean" on.
Your thoughts please,
________________________________________________________________________________
| From: | "Jim Pack" <jpack(at)igs3.com> |
| Subject: | Re: Avionics bus |
In reality, it doesn't need a general AV master, it simply needs a dedicated
switch to that piece of avionics - only because one was not built into the
unit itself.
- Jim
----- Original Message -----
From: "Shannon Knoepflein" <kycshann(at)kyol.net>
Subject: RE: AeroElectric-List: Avionics bus
>
> It is actually possible that Greg's system needs protected, just like my
> Chelton, due to it opening and closing files during bootup. I think
> Greg's is more PC based so it might be better at handling this, but the
> Chelton isn't as forgiving.
>
> These computers are really the ONLY thing that even has a chance of
> needing the AV Master, as Bob has shown many times.
>
________________________________________________________________________________
| Subject: | Z-13 and Dual Electronic Ignitions |
| From: | "Don Honabach" <don(at)pcperfect.com> |
>> As I have mentioned before, there is ONE case where an avionics
master is really needed. It's to protect the Chelton EFIS computer
during its boot-up stage when its opening and closing config files. If
it reboots while it has one of these files open, corruption of this file
is a possibility, rendering the unit useless.
If you wanted to keep a clean panel with one less switch, wouldn't it
possible to put a capacitor at the power input leads to act as a small
battery/noise filter for the device to take care of the temporary sags
in voltage during startup?
>> Now, I won't go as far to say that this behavior is acceptable and
correct, but the fact is it does exist (whereas ALL of the other calls
for an avionics master are baseless, as you say).
For such a nice unit, I'm surprised it doesn't have a better startup
design.
Regards,
Don
-----Original Message-----
From: Shannon Knoepflein [mailto:kycshann(at)kyol.net]
Subject: RE: AeroElectric-List: Z-13 and Dual Electronic Ignitions
-->
Bob,
As I have mentioned before, there is ONE case where an avionics master
is really needed. It's to protect the Chelton EFIS computer during its
boot-up stage when its opening and closing config files. If it reboots
while it has one of these files open, corruption of this file is a
possibility, rendering the unit useless.
Now, I won't go as far to say that this behavior is acceptable and
correct, but the fact is it does exist (whereas ALL of the other calls
for an avionics master are baseless, as you say).
I think this area is one that might need to be addressed in the future
as more things go electronic and computerized. Hopefully, the
manufacturers will make them immune to this, but, if not, it will need
to be addressed by a Z drawing.
My solution and suggestion to a solution is to create an avionics buss
that also doubles as an essential (or endurance) buss, that is fed by an
alternate feed switch. I also suggest this architecture to people that
are uncomfortable sleeping at night without their avionics behind a
master, whether it's for unfounded passed on blurb, or if its just for
convenience. This architecture adds one switch (av master) to a typical
Z14 with ess buss, and really provides the best of both worlds.
Shannon
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Robert L. Nuckolls, III
Subject: Re: AeroElectric-List: Z-13 and Dual Electronic Ignitions
>
> >
>Bob,
>The main incentive I had for going down this path was finding a simpler
>method of incorporating the dreaded avionics bus into your essential
>bus architecture. I know this is a major point of contention for you,
>but I find myself dealing with the reality of a manufacturers
>recommendation to provide protection for certain components, and I'm
>too far into the stream to change horses. More important to me than
>the failure modes was finding a way to simplify by combining the
>avionics bus and the essential bus by isolating the main and essential
>busses during starting. The aux bus backup was a lower priority
>consideration to allow me to have some of these sensitive instruments
>powered up during start without exposure to the brownout situation you
>have discussed, and secondarily to provide a second power source for my
>electronic flight instruments. I know this kind of talk probably makes
>you crazy, but in my never ending quest to expose my ignorance of
>electronics, I was compelled to present it to you.
> I would appreciate your consideration of this idea.
A little disappointed perhaps but not crazy. And the goal
here is not to please me or any body else on the list.
I've often suggested that folks are better off with a system
they understand and are comfortable with than to be worrying
about something unique to their level of understanding.
Keep in mind that the vast majority of SE aircraft flying today
are wired not unlike the CessnaBeechPiperMooneys of decades
gone by . . . including OBAM aircraft. Airplanes wired
per the Z-drawings are rare in comparison with the total
fleet of aircraft.
When I ask people to justify their wish to modify any
of the systems we've published, it's not because I have
any notion of convincing them to "do it my way." My
query is aimed at acquiring insight as to some point
of engineering I may have overlooked. The Z-drawings
have evolved a lot over the last 10 years and I'd be
foolish to believe they should not evolve further.
My job is not to persuade you to do anything. My
job is to help you understand how the system works.
Your job is to craft a system that is not distracting
because of concerns or misunderstood operation. So
in answer to your questions:
You can certainly add a switch in series with normal
feedpath diode to service as an "avionics master"
You don't need to use a contactor for an aux battery
unless the battery is robust enough to aid in cranking
and/or it is your intent NOT to use it to assist the main
battery in cranking. Indeed, when the automatic aux
battery management concept was published in Sport Aviation
about 6 years ago, the aux battery was perhaps a 4-6 a.h.
device connect to the bus via a 30A power relay like our
S704-1.
May I suggest the following actions which may work
toward mitigating your concerns? Give me a list of
folks who have supplied you with equipment that they
claim is "sensitive" . . and let's at least ask them
to provide a justification for their assertions
based on physics.
I presume you followed the conversation
with Electronics International over the last two weeks.
It turns out that they haven't a clue as to why their
products should or should not be "protected".
While they claimed credit for full compliance under
TSO requirements that include DO-160 testing, they
didn't truly understand the significance of the tests
they paid money to accomplish. Nor did they understand
the significance of that testing with respect to their
customer's reasonable expectations.
In EVERY case I've looked at over the past 15 years,
not one company asking for an "avionics master switch"
was able to enlighten me with an explanation. In more than
half the cases, they admitted that there was no
justification and that the topic of avionics master
switch was part of the boiler-plate used to craft installation
manuals since the 60's and nobody has ever bothered to
review that requirement and take it out of the book.
I don't know if the outcome of such an exercise would influence
the way you configure your airplane and it doesn't matter.
Bottom line is that what ever goes into YOUR airplane
should minimize your worries as an owner and maintainer
of the airplane so that you can maximize your performance
as the pilot of that airplane.
Bob . . .
direct advertising on the Matronics Forums.
________________________________________________________________________________
| From: | "John Slade" <sladerj(at)bellsouth.net> |
> It is actually possible that Greg's system needs protected, just like my
> Chelton, due to it opening and closing files during bootup.
I don't understand this. I thought all the EFIS/ONE data was either rom
based or on a CD/DVD. Either way I don't see how you can corrupt a file
unless you're running off writable media. Am I wrong?
John Slade
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Source for Pins & Extraction tools |
>
>Hi Everyone,
>
>I noticed that when crimping the machined pins for the D style
>connectors that the insulation on the wire usually ends up exposing
>about a 1mm of wire despite my best attempts to keep the insulation
>right next to the pin during the crimp.
>Obviously 1mm of wire showing isn't going to be a problem, but it bugs
>me. Is this normal for these type of pins/connectors? Has anyone been
>able to keep a 0 tolerance on the wire shown at the back end of the pin?
Better to have strands exposed this amount than to have the
insulation pushed against the pin . . . the goal is to have
strands go all the way to the bottom of the crimp cup. If
Insulation rides against the pin, there is a question as to
sufficient strip length. When the pin is inserted into the
connector shell, this small gap is down inside the rear
molding of the connector and not visible.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Supporting the other ends of our gyros |
>
>
>Fellow listers,
>
>What are you doing (have you done) to support the forward (back) ends of
>your long gyros?
>
>A couple of mine will go through the next forward bulkhead so I can
>probably rivet on a piece of angle and clamp the gyro to that. One (AI)
>is too short but is right on top of another (HSI) that goes through the
>next forward bulkhead - I was thinking of making up a spacer to put those
>two together and clamp them together using the support on the one that
>goes all the way through to hold both. Another of mine (S-Tec30 TC/AP) is
>also too short and is not close enough to another one to "lean" on.
>
>Your thoughts please,
Does the manufacturer suggest support at both ends?
Be careful that you don't make things worse than you
think they are already. Most instruments are designed
to be mounted from the face. I you were to add "support"
to a long instrument with brackets to some forward
structure, you may find that you're really adding support
to the panel via the case on the instrument. I can see
this causing failure of the instrument mounting provisions
due to overload.
Unless what you propose is recommended by the manufacturer,
proceed with caution.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>
>It is actually possible that Greg's system needs protected, just like my
>Chelton, due to it opening and closing files during bootup. I think
>Greg's is more PC based so it might be better at handling this, but the
>Chelton isn't as forgiving.
>
>These computers are really the ONLY thing that even has a chance of
>needing the AV Master, as Bob has shown many times.
Is this an "Avonics Master" or a simple switch that accommodates
some unique requirement of the system? Last time I talked
to Greg, he said that there was no hazard to his system
due to brownout . . . it would just have to reboot thus
taking longer to get ready to go to work. So big deal . . .
If the Chelton system has any chance of going brain-dead
due to brownout, how would one propose to deal with a situation
like hard fault on a pitot heat line that opens the
fuse (or worse yet) breaker by putting a momentary load
of 300A or more on the system? There are OTHER causes of
reduced system voltage than engine cranking and they
might happen in flight (That's why we use fuses and
breakers).
I'm not sure I'd have much confidence in a system that
couldn't get stood back up after an unexpected brownout of
any duration, rise and fall times and amplitude. This
might be more of a reason for the ever popular Band-Aid
battery diode fed from the bus. Momentary brownouts of
any character are washed out by the battery.
There's no excuse for not being able to handle this
kind of event but if the manufacturer is insistent,
then a small diode fed support battery is the 100%
solution.
Bob . . .
________________________________________________________________________________
| Subject: | Source for Pins & Extraction tools |
| From: | "Don Honabach" <don(at)pcperfect.com> |
Bob,
>> When the pin is inserted into the connector shell, this small gap is
down inside the rear molding of the connector and not visible.
Thanks - I really appreciate you taking the time to give full answers.
Seems like a lot of folks that give advice either don't know the whys or
won't take the time to explain.
Any way, I'll have to look for different connector shells. My current
one for my UPS GPS/COMM rids the pin right to the back end so any
exposed wire is visible which started my concern (just doesn't have that
clean look and I'd rather think that the insulation was helping to
support the wire). I'll try some different brands of shells and if the
installation sits inside the connector shell I'll be a happy camper.
Thanks!
Don
-----Original Message-----
From: Robert L. Nuckolls, III [mailto:bob.nuckolls(at)cox.net]
Subject: RE: AeroElectric-List: Source for Pins & Extraction tools
-->
>-->
>
>Hi Everyone,
>
>I noticed that when crimping the machined pins for the D style
>connectors that the insulation on the wire usually ends up exposing
>about a 1mm of wire despite my best attempts to keep the insulation
>right next to the pin during the crimp.
>Obviously 1mm of wire showing isn't going to be a problem, but it bugs
>me. Is this normal for these type of pins/connectors? Has anyone been
>able to keep a 0 tolerance on the wire shown at the back end of the
>pin?
Better to have strands exposed this amount than to have the
insulation pushed against the pin . . . the goal is to have
strands go all the way to the bottom of the crimp cup. If
Insulation rides against the pin, there is a question as to
sufficient strip length. When the pin is inserted into the
connector shell, this small gap is down inside the rear
molding of the connector and not visible.
Bob . . .
direct advertising on the Matronics Forums.
________________________________________________________________________________
| Subject: | Magneto buzz box circuit |
| From: | "David" <David(at)ChalmersFamily.com> |
I did play with an ohmmeter for a while but found it very difficult to
identify the tiny change in resistance. Today I hooked up a 555
oscillator. I took the output through a 100 ohm resistor to an 8W mini
speaker and put the points across the speaker. It was fairly easy to
detect the change in volume, however there was still some noise even
when the points were supposed to be closed - dirty points?, bad
connection? Anyway, I found something that worked better. I powered the
555 from a 9V battery through the points. This causes the oscillator to
change in frequency when the points open - much easier to detect. I
don't have a decoupling capacitor on the 555 supply and I assume this is
facilitating the effect. Anyway it works well enough. I did destroy one
555 before I put a diode across the power lines to protect it. Probably
should add some overvoltage protection too. If anyone has a 'proper'
circuit design I would be interested to see how it should be done.
Thanks
Dave Chalmers
-----Original Message-----
From: Gary Casey [mailto:glcasey(at)adelphia.net]
Subject: AeroElectric-List:
<>
This is probably heresy, but I use a simple ohmmeter. It has to be a
fairly
good one to detect the difference between the resistance of the coil
(less
than 1 ohm) and the shorted points. I ONLY connect the ohmmeter when I
am
right the correct timing value and then bump the crank very slowly. Do
it
with any speed and there will occur a voltage spike when the points open
that could damage the ohmmeter. The easy way is to back the crank up
and
turn it forward, listening for the impulse coupling click at about TDC.
Then back the crank up to just before 25 BTC and very slowly go forward.
A
little time consuming, but if you only do it once in a great while it
works.
Just don't send me a bill for your blown-up ohmmeter.
Gary Casey
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
Bob,
Per your email on your filter test on the strobe power supply, which do
you see as the better solution? The LC filter minimizes the ripple as
well as just the larger C filter, but the LC filter leaves a little
spike on the transient. Do you suggest using the LC, or just the large
C filter?
---
Shannon Knoepflein <---> kycshann(at)kyol.net
Yup, did such a study on a builder's proposed
strobe light a few years ago. We were looking at both
noise and the periodic, erratic nature of input current
draw for his power supply. See the plot of this
data at:
http://216.55.140.222/temp/Strobe_Plot.pdf
Here one may observe the effects of various filter
techniques tried for noise mitigation. The top
plot is current curve using one of the radio shack
filters as described in:
http://www.aeroelectric.com/articles/filter/filter.html
The second plot places a single 10,000 uf cap across
the power supply input.
The third plot shows unfiltered current noise.
In the second plot, we see a data value deduced from
area under the current curve that says this strobe
uses 1.3 ampere seconds of current per cycle. The
ENERGY consumed by this particular strobe is
1.3 a-s/flash x 14v = 18.2 Joules/flash input power.
I think this was a 10 Joule/flash system so this
puts overall efficiency at about 55%. Probably
average for products of this type.
The peak current was measured at 2.7 amps. Average
current is 0.9 x 1.3 or 1.17 amps. I seem to recall
the instructions for this system called for a 5A
breaker . . . a 2A breaker would probably have worked
nicely too.
Bob . . .
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
Sounds like it's not a problem with the EFIS/ONE (I never said it was,
just said it was a possibility), whereas it could be with the Chelton.
Again, I'm not sure it is, I'm just going by what they tell me. I
should have an opportunity to test it soon and see I can actually get it
to do it. Honestly, I don't think its possible, but it's the only thing
I've ever heard from a manufacturer that would warrant any type of
master or switch added to turn it off.
I certainly agree that if they (chelton) felt this could be a problem,
they should have added a power switch to the unit itself. My ONLY
complaint with the system so far.
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of John
Slade
Subject: RE: AeroElectric-List: Avionics bus
> It is actually possible that Greg's system needs protected, just like
my
> Chelton, due to it opening and closing files during bootup.
I don't understand this. I thought all the EFIS/ONE data was either rom
based or on a CD/DVD. Either way I don't see how you can corrupt a file
unless you're running off writable media. Am I wrong?
John Slade
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
True.
I just chose to combine this little buss that needed to be created for
the Chelton and the ESS bus, and back it up with an ALT FEED. This may
not have been the best choice for everyone, but it was for me, as it is
how I wanted it configured and is something I understand and allows me
to immediately shed loads to the ESS bus. Again, maybe not for
everyone, but I weighed the pros and cons of all systems, and after
doing much research for answers, this is what was best for me IMHO, and
that's what important. The system is simple to understand, easy to use,
and backed up....
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jim
Pack
Subject: Re: AeroElectric-List: Avionics bus
In reality, it doesn't need a general AV master, it simply needs a
dedicated
switch to that piece of avionics - only because one was not built into
the
unit itself.
- Jim
----- Original Message -----
From: "Shannon Knoepflein" <kycshann(at)kyol.net>
Subject: RE: AeroElectric-List: Avionics bus
>
> It is actually possible that Greg's system needs protected, just like
my
> Chelton, due to it opening and closing files during bootup. I think
> Greg's is more PC based so it might be better at handling this, but
the
> Chelton isn't as forgiving.
>
> These computers are really the ONLY thing that even has a chance of
> needing the AV Master, as Bob has shown many times.
>
________________________________________________________________________________
| From: | Mark Phillips <ripsteel(at)edge.net> |
| Subject: | 100 % Solution (diode-fed support batt-was Avionics |
bus)
Would a small battery such as the 1.3 Ah Panasonic DigiKey sells (1.3 lbs, under
$20) tied
directly to the e-bus maintain full voltage on the bus during engine start or any
other
low-voltage condition, thus mitigating these concerns? This assumes equipment
of concern
were fed from this bus. The e-bus supply diode would prevent discharge back to
the main bus,
and the e-bus alternate feed would normally be off, but a diode in this feed would
do
likewise. This seems an obvious way to put the whole issue to bed unless there
are other
concerns such as charging issues for the backup battery. This also adds the benefit
of
"some" additional endurance to the bus, and would even power the bus briefly when
the main
battery post breaks off (tounge-in-cheek on that one, but.......!) Sized appropriately,
this
battery could actually support the e-bus for duration-of-flight, saving the main
for
arrival/landing ops exclusively, as another option. Is this what you mean by "diode
fed
support battery" and why is this not a common solution?
Mark Phillips
>
> There's no excuse for not being able to handle this
> kind of event but if the manufacturer is insistent,
> then a small diode fed support battery is the 100%
> solution.
>
> Bob . . .
>
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
Bob,
Yes, its an avionics master switch that activates a solid state relay
(Eric Jones) that feeds power from the AUX buss through a superdiode
(Eric) to an
ESS/AVIONICS buss. This ESS/AVIONICS buss is backed up through a ALT
FEED switch.
Sounds like Greg's system won't do this brownout, whereas the Chelton at
least has the possibility. Once it get up and running fully, I will
test the Chelton and see if I can get it to do it. From what Chelton
tells me, it is opening and closing config files during bootup, and
connecting to the engine/air data unit and the AHRS, and if it shuts
down at the right time, it can corrupt things. Sounds like a bit of
hocus pocus to me, but I have no choice but to believe them until I can
verify it. This is my ONLY complaint about this system...it should
really just have a power switch on it.
Per your concern about brownout during flight...once the Chelton is
booted up and running, killing power is not a concern. It's just
turning it off when it is first booting up. So, if the pitot failed and
killed the buss, the system would shut down with no affect. Fist off,
the pitot is on not on the AUX/ESS buss, so it failing wouldn't affect
the primary flight dislay anyway. However, if it was, I would flip the
ALT/BATT switch off and the AUX/ESS ALT FEED switch and fly straight and
level while the system comes back to life, boots up, and calibrates
itself. (I would do this using the backup attitude gyro which is also on
the ESS buss). After I have things booted back up and normal, at this
point, I would put the GAMI Supplenator into self excite mode (doesn't
need a battery to produce current) and it would make 35A without being
connected to the battery.
I have lots of confidence in the system. Its being built for the Alaska
Capstone project, and is the first EFIS to get blanket FAA approval for
over 650 airplanes. The system has been rigorously tested (go to their
website, www.cheltonflightsystems.com and go to the Sierra line and
watch the video of the lightning test). And, I think when it comes down
to it, I will find out that the system doesn't have any problems even
with this little brownout issue.
If I find it to be an issue, I will consider the diode and battery.
Yet, with my current configuration, I don't see how this would enhance
the system.
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Robert L. Nuckolls, III
Subject: RE: AeroElectric-List: Avionics bus
>
>
>It is actually possible that Greg's system needs protected, just like
my
>Chelton, due to it opening and closing files during bootup. I think
>Greg's is more PC based so it might be better at handling this, but the
>Chelton isn't as forgiving.
>
>These computers are really the ONLY thing that even has a chance of
>needing the AV Master, as Bob has shown many times.
Is this an "Avonics Master" or a simple switch that accommodates
some unique requirement of the system? Last time I talked
to Greg, he said that there was no hazard to his system
due to brownout . . . it would just have to reboot thus
taking longer to get ready to go to work. So big deal . . .
If the Chelton system has any chance of going brain-dead
due to brownout, how would one propose to deal with a situation
like hard fault on a pitot heat line that opens the
fuse (or worse yet) breaker by putting a momentary load
of 300A or more on the system? There are OTHER causes of
reduced system voltage than engine cranking and they
might happen in flight (That's why we use fuses and
breakers).
I'm not sure I'd have much confidence in a system that
couldn't get stood back up after an unexpected brownout of
any duration, rise and fall times and amplitude. This
might be more of a reason for the ever popular Band-Aid
battery diode fed from the bus. Momentary brownouts of
any character are washed out by the battery.
There's no excuse for not being able to handle this
kind of event but if the manufacturer is insistent,
then a small diode fed support battery is the 100%
solution.
Bob . . .
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
| Subject: | WX900 Stormscope |
Here's the best I can do for you. This is how mines wired (ignore stuff
to right):
WX-1 WX500 Power +12V 22-3S 18 WHT
WX-2 WX500 Ground 22-3S - W/BLU
WX-3 WX500 RS-232 TX 22-3S 18 WHT
WX-4 WX500 RS-232 RX 22-3S - W/BLU
WX-5 WX500 RS-232 Ground 22-3S - W/ORG
WX-6 WX500 Shield 22-3S - SHIELD
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
DHPHKH(at)aol.com
Subject: AeroElectric-List: WX900 Stormscope
Gang,
Anybody have a pinout and/or installation manual for a WX-900
Stormscope?
Dan Horton
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: 100 % Solution (diode-fed support |
batt-was Avionics bus)
>
>Would a small battery such as the 1.3 Ah Panasonic DigiKey sells (1.3 lbs,
>under $20) tied
>directly to the e-bus maintain full voltage on the bus during engine start
>or any other
>low-voltage condition, thus mitigating these concerns?
Sure. You'd have to fit it with some kind of mini-contactor
that operates in conjunction with either the DC Power Master
switch or the E-bus alternate feed switch. You would also
want to make sure the E-bus alternate feed switch is OFF
during engine cranking.
Or . . one could simple add a third dc power control
switch for this battery . . . and write its proper usage
into the checklists . . . I think I lean more toward an
automatic control/selection.
> This assumes equipment of concern
>were fed from this bus. The e-bus supply diode would prevent discharge
>back to the main bus,
>and the e-bus alternate feed would normally be off, but a diode in this
>feed would do
>likewise. This seems an obvious way to put the whole issue to bed unless
>there are other
>concerns such as charging issues for the backup battery. This also adds
>the benefit of
>"some" additional endurance to the bus, and would even power the bus
>briefly when the main
>battery post breaks off (tounge-in-cheek on that one, but.......!) Sized
>appropriately, this
>battery could actually support the e-bus for duration-of-flight, saving
>the main for
>arrival/landing ops exclusively, as another option. Is this what you mean
>by "diode fed
>support battery" and why is this not a common solution?
If you make this battery large enough for service
as the endurance bus battery, then one might as well
do a two-battery installation. Drive the main bus
with the main battery, drive e-bus from the aux battery
bus, just don't close the aux battery contactor until
after engine start (aux battery management module?)
and then write the engine start procedure for e-bus
alternate feed switch to be closed for engine start.
Using two contactors for equal sized batteries makes
BOTH batteries available for any task if needs be
and puts you back into the battery-a-year-swap
mode for preventative maintenance. I'll think about
this some more today
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>
>Bob,
>
>Per your email on your filter test on the strobe power supply, which do
>you see as the better solution? The LC filter minimizes the ripple as
>well as just the larger C filter, but the LC filter leaves a little
>spike on the transient. Do you suggest using the LC, or just the large
>C filter?
Those traces were only a demonstration of what the supply
does under various conditions and were not intended to
be a recommendation for installation in any particular
system.
Put your strobe system in barefoot and see if you have
a noise problem. Don't recommend putting in solutions
for problems that don't exist.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Source for Pins & Extraction tools |
>
>Bob,
>
> >> When the pin is inserted into the connector shell, this small gap is
>down inside the rear molding of the connector and not visible.
>
>Thanks - I really appreciate you taking the time to give full answers.
>Seems like a lot of folks that give advice either don't know the whys or
>won't take the time to explain.
>
>Any way, I'll have to look for different connector shells. My current
>one for my UPS GPS/COMM rids the pin right to the back end so any
>exposed wire is visible which started my concern (just doesn't have that
>clean look and I'd rather think that the insulation was helping to
>support the wire). I'll try some different brands of shells and if the
>installation sits inside the connector shell I'll be a happy camper.
Oh yeah, I've seen those short moldings at RAC . . . and yes,
you can see our "wires hanging out" when those connectors
are used. All of the connectors I buy/use have the longer
moldings. In either case, it's purely cosmetic. There's
no risk to the functionality of the system because of the
exposed wire.
Bob . . .
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
I understand don't solve a problem that isn't there. Thats not exactly
what I was asking. What I was trying to understand is which one do you
consider to be a better filter?
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Robert L. Nuckolls, III
Subject: Re: AeroElectric-List: Filtering
>
>
>Bob,
>
>Per your email on your filter test on the strobe power supply, which do
>you see as the better solution? The LC filter minimizes the ripple as
>well as just the larger C filter, but the LC filter leaves a little
>spike on the transient. Do you suggest using the LC, or just the large
>C filter?
Those traces were only a demonstration of what the supply
does under various conditions and were not intended to
be a recommendation for installation in any particular
system.
Put your strobe system in barefoot and see if you have
a noise problem. Don't recommend putting in solutions
for problems that don't exist.
Bob . . .
________________________________________________________________________________
| From: | "Jim Pack" <jpack(at)igs3.com> |
If your panel only provided room to display readings for either volts or
amps (but not both), what would you all recommend displaying and why?
- Jim
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
Why not display both on the JPI volt/amp gauge? It's a little
rectangle, like 1x3 I think, and will display both. I have one on my
panel that monitors both busses for amperage and voltage, and can also
get voltage from the battery side or the alternator side. See my panel
at http://shannon.v8eaters.com/images/lancair it's a *.pdf, for a
picture of the display and the associated switches.
If this is not an option, I think I would want to just see voltage, and
have a switch where I can see it at the alternator or at the battery.
That will tell you what you need to know I think.
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jim
Pack
Subject: AeroElectric-List: volts vs amps
If your panel only provided room to display readings for either volts or
amps (but not both), what would you all recommend displaying and why?
- Jim
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: volts vs amps |
In a message dated 5/12/03 11:35:32 AM Central Daylight Time,
kycshann(at)kyol.net writes:
> If this is not an option, I think I would want to just see voltage, and
> have a switch where I can see it at the alternator or at the battery.
> That will tell you what you need to know I think.
>
Good Morning Shannon,
I use an Electronics International Loadmeter in a similar way, but I am
curious as to how you isolate the battery and/or the alternator from the
system so that you can read specific voltages. Mine always shows the overall
system voltage regardless of where it is measured. Unless there is an unusual
resistance in the system, isn't that the way it should work? I guess any
difference would indicate a serious problem.
The load function is selectable to either alternator or the battery via
separate shunts. Works great and all in one two and one-eighth inch
instrument.
Happy Skies,
Old Bob
Happy Skies,
Old Bob
________________________________________________________________________________
| From: | "Dan Checkoway" <dan(at)rvproject.com> |
| Subject: | cutting heavy gauge wire, contactor diodes, copper |
alloys
1) What's the easiest and cleanest way to cut 2 awg wire?
2) What type of diode(s) should be used on battery/starter contactors? I
couldn't find any spec on it in the AEC book. I have a 3-terminal battery
contactor (ES 24115 from Van's) and a 4-terminal starter contactor (ES
24021). I've checked the archives and found varying info...1N5xxx or 1N4xxx
or other?
3) Is there a significant difference between copper alloys 101 &
110...specific case being an .062" or .064" x 1/2" connector between
contactors.
Thanks in advance,
)_( Dan
RV-7 N714D
http://www.rvproject.com
________________________________________________________________________________
| Subject: | Re: cutting heavy gauge wire, contactor |
diodes, copper alloys
Alloy 101 is Oxygen free, Ultra pure copper, contains virtually no oxygen
and is easy to weld and braze. For high temp applications, terminal lugs,
wire connectors, and seals. Also VERY EXPENSIVE!! .064, 12" x12", 40 bucks!!!
Alloy 110. Corrosion resistant highly ductile and very conductive. For
electrical and general purpose uses.
Right out of the McMaster-Carr catalog.
>
>1) What's the easiest and cleanest way to cut 2 awg wire?
>
>2) What type of diode(s) should be used on battery/starter contactors? I
>couldn't find any spec on it in the AEC book. I have a 3-terminal battery
>contactor (ES 24115 from Van's) and a 4-terminal starter contactor (ES
>24021). I've checked the archives and found varying info...1N5xxx or 1N4xxx
>or other?
>
>3) Is there a significant difference between copper alloys 101 &
>110...specific case being an .062" or .064" x 1/2" connector between
>contactors.
>
>Thanks in advance,
>)_( Dan
>RV-7 N714D
>http://www.rvproject.com
>
>
Scott Bilinski
Eng dept 305
Phone (858) 657-2536
Pager (858) 502-5190
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
Hey Old Bob, Put a volt sense wire on the ANL from the alternator, and
then put one on the other side of the battery contactor. Flip the
battery contactor off, and you can see what's going on on the battery
and alternator independently by flipping the switch. If the contactor
is on, yes, they should read the same. This could indicate a voltage
drop problem too. Not really necessary, but I think it might prove
useful in diagnosis. What do you think?
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
BobsV35B(at)aol.com
Subject: Re: AeroElectric-List: volts vs amps
In a message dated 5/12/03 11:35:32 AM Central Daylight Time,
kycshann(at)kyol.net writes:
> If this is not an option, I think I would want to just see voltage,
and
> have a switch where I can see it at the alternator or at the battery.
> That will tell you what you need to know I think.
>
Good Morning Shannon,
I use an Electronics International Loadmeter in a similar way, but I am
curious as to how you isolate the battery and/or the alternator from the
system so that you can read specific voltages. Mine always shows the
overall
system voltage regardless of where it is measured. Unless there is an
unusual
resistance in the system, isn't that the way it should work? I guess any
difference would indicate a serious problem.
The load function is selectable to either alternator or the battery via
separate shunts. Works great and all in one two and one-eighth inch
instrument.
Happy Skies,
Old Bob
Happy Skies,
Old Bob
________________________________________________________________________________
| From: | "Don Honabach" <don(at)pcperfect.com> |
>> Why not display both on the JPI volt/amp gauge?
I don't know if the issue ever got resolved, but JPI actually tried or
sued Matronics awhile back. Ever since then, I've sworn never to use any
of their instruments and won't consider them for any part of my panel
space. Here's a link that has some background:
http://home.earthlink.net/~timrv6a/jpi.html
Regards,
Don
-----Original Message-----
From: Shannon Knoepflein [mailto:kycshann(at)kyol.net]
Subject: RE: AeroElectric-List: volts vs amps
-->
Why not display both on the JPI volt/amp gauge? It's a little
rectangle, like 1x3 I think, and will display both. I have one on my
panel that monitors both busses for amperage and voltage, and can also
get voltage from the battery side or the alternator side. See my panel
at http://shannon.v8eaters.com/images/lancair it's a *.pdf, for a
picture of the display and the associated switches.
If this is not an option, I think I would want to just see voltage, and
have a switch where I can see it at the alternator or at the battery.
That will tell you what you need to know I think.
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jim
Pack
Subject: AeroElectric-List: volts vs amps
If your panel only provided room to display readings for either volts or
amps (but not both), what would you all recommend displaying and why?
- Jim
direct advertising on the Matronics Forums.
________________________________________________________________________________
| From: | "Don Honabach" <don(at)pcperfect.com> |
Hey Guys,
Just a follow up on my prior comments about JPI. I've copied in the text
from Matt after the issue was resolved (see below) so you have all the
facts. For me though, the character of JPI was shown by their initial
actions and re-actions, and I can't in good faith support such a
company.
---
Dear Listers,
After seven months of negotiations, JP Instruments, Inc. and Matronics
have reached a mutually agreeable settlement. As most of you are aware,
in February of this year, JP Instruments, Inc. alleged that Matronics'
use of the trademark "FuelScan" with its aircraft fuel management system
infringed upon JP Instruments, Inc's trademark "Scanner" for engine
temperature indicators. JP Instruments, Inc. requested that Matronics
discontinue the use of the "FuelScan" mark. After considerable
negotiations, we have come to an agreement whereby JP Instruments, Inc.
will purchase the FuelScan trademark and, if necessary, assist in paying
the cost of Matronics' adoption of a new trademark. Matronics will
continue to sell and market its aircraft fuel management system under
the FuelScan trademark until a phase-out period of up to one year is
completed. This will allow Matronics time to sell out its current stock
of units marked with the FuelScan trademark and to develop a new
trademark.
While negotiations have been a bit trying at times, I would like to say
that I am satisfied with the outcome, and feel that JP Instruments, Inc.
has treated Matronics and me fairly in this matter. Furthermore, I
would encourage you to consider JP Instruments for your aircraft
avionics in the future as they manufacture an excellent product line.
Finally, I would like to thank everyone from around the world for their
support and consideration in this matter. I was quite moved by the
support - both financial and in the form of letters and comments - that
builders and pilots provided me and my company during this time. I
never felt alone during this period, and so very much appreciated the
encouragement from thousands of my friends! Thank you so very much!
Best regards,
Matt Dralle
President, Matronics
-----Original Message-----
From: Shannon Knoepflein [mailto:kycshann(at)kyol.net]
Subject: RE: AeroElectric-List: volts vs amps
-->
Why not display both on the JPI volt/amp gauge? It's a little
rectangle, like 1x3 I think, and will display both. I have one on my
panel that monitors both busses for amperage and voltage, and can also
get voltage from the battery side or the alternator side. See my panel
at http://shannon.v8eaters.com/images/lancair it's a *.pdf, for a
picture of the display and the associated switches.
If this is not an option, I think I would want to just see voltage, and
have a switch where I can see it at the alternator or at the battery.
That will tell you what you need to know I think.
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Jim
Pack
Subject: AeroElectric-List: volts vs amps
If your panel only provided room to display readings for either volts or
amps (but not both), what would you all recommend displaying and why?
- Jim
direct advertising on the Matronics Forums.
________________________________________________________________________________
| From: | "Jim Pack" <jpack(at)igs3.com> |
| Subject: | AutoPilot Disconnect |
In october last year a link was provided to an autopilot disconnect
schematic. The link was:
http://216.55.140.222/temp/AP_Disconnect.pdf
The link is dead, does anyone have a copy of the schematic?
Thanks,
Jim
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: cutting heavy gauge wire, contactor |
diodes, copper alloys
>
>1) What's the easiest and cleanest way to cut 2 awg wire?
See http://www.aeroelectric.com/Catalog/tools/hdc-1a.jpg
and http://www.aeroelectric.com/Catalog/tools/hdc-1b.jpg
and http://www.aeroelectric.com/Catalog/BCcatalog.html
>2) What type of diode(s) should be used on battery/starter contactors? I
>couldn't find any spec on it in the AEC book. I have a 3-terminal battery
>contactor (ES 24115 from Van's) and a 4-terminal starter contactor (ES
>24021). I've checked the archives and found varying info...1N5xxx or 1N4xxx
>or other?
The diode needs to be rated for 15v or more and be capable
of carrying the same current that it takes to energize the
contactor (1 to 5A) for a few milliseconds. About any
diode rectifier is electrically suited to the task. 1N400x
series are fine but they are rather small, sometimes glass
devices that are fragile compared to the 1N540x series
devices that are always 1/4" diam plastic and 20AWG leads.
If you look at the diodes we supply on the S700 series
contactors at
http://www.aeroelectric.com/Catalog/switch/s701-1l.jpg
and http://www.aeroelectric.com/Catalog/switch/s701-2.jpg
. . . you can see how the mechanically more robust
3A diodes lend themselves to the task.
ANY diode you can find will work electrically . . .
chose for convenience of application.
>3) Is there a significant difference between copper alloys 101 &
>110...specific case being an .062" or .064" x 1/2" connector between
>contactors.
I presume you're talking about material for bus
bar stock to substitute for short pieces of wire
with terminals . . . 1/2" x .064 of any copper alloy
including sheet brasses is fine. I prefer brass because
it's easier to work with. Copper is soft and tends to
snag a drill.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| Subject: | Re: Z-13 and Dual Electronic Ignitions |
| From: | Joel Harding <cajole76(at)ispwest.com> |
On Saturday, May 10, 2003, at 10:44 AM, Robert L. Nuckolls, III wrote:
>
> May I suggest the following actions which may work
> toward mitigating your concerns? Give me a list of
> folks who have supplied you with equipment that they
> claim is "sensitive" . . and let's at least ask them
> to provide a justification for their assertions
> based on physics.
Bob,
I already provided information about E.I. which I think you pursued as
far as you could take it. Here's another from S-tec if you want to
give it a shot. I can probably get more if you would like. My concern
is that, even if this is an unnecessary precaution, with this type of
recommendation there could very easily be some warranty difficulties if
it's not followed.
> I thought I did explain about the avionics buss. You definitely need
an
> avionics buss for the autopilot. The system 20 has two separate power
> inputs. One for the turn coordinator which is powered directly off
the
> battery buss, and another for the autopilot that needs to be on a
separate
> avionics buss. You can damage the autopilot and other equipment
during
> engine start if it is on the same buss.
> Regards,
> Butch Nimmo
> Repair Station Supervisor
As always, thanks for your continued involvement in furthering our
education.
Joel Harding
> I presume you followed the conversation
> with Electronics International over the last two weeks.
> It turns out that they haven't a clue as to why their
> products should or should not be "protected".
> While they claimed credit for full compliance under
> TSO requirements that include DO-160 testing, they
> didn't truly understand the significance of the tests
> they paid money to accomplish. Nor did they understand
> the significance of that testing with respect to their
> customer's reasonable expectations.
>
> In EVERY case I've looked at over the past 15 years,
> not one company asking for an "avionics master switch"
> was able to enlighten me with an explanation. In more than
> half the cases, they admitted that there was no
> justification and that the topic of avionics master
> switch was part of the boiler-plate used to craft installation
> manuals since the 60's and nobody has ever bothered to
> review that requirement and take it out of the book.
>
> I don't know if the outcome of such an exercise would influence
> the way you configure your airplane and it doesn't matter.
> Bottom line is that what ever goes into YOUR airplane
> should minimize your worries as an owner and maintainer
> of the airplane so that you can maximize your performance
> as the pilot of that airplane.
>
> Bob . . .
>
>
> _-
> ======================================================================
> _-
> ======================================================================
> _-
> ======================================================================
> _-
> ======================================================================
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: volts vs amps |
>
>If your panel only provided room to display readings for either volts or
>amps (but not both), what would you all recommend displaying and why?
>
>- Jim
Ammeters and voltmeters are useful only when things are NOT going
well. Things WORK most of the time so a simple low volts warning
light accurately set to operate below 13.0 volts is the primary
flight instrument for failure warning. If you are in flight
when the light comes on, the existence or absence of a voltmeter
or ammeter of any kind is not an issue because you're going to
switch immediately to "plan-b" . . . now, if you want something
to watch and worry about during plan-b operations, you need a
voltmeter on the e-bus. However, if it's your standard practice
to conduct good preventative maintenance on the airplane's battery,
then you KNOW that the battery is going to get you on the ground
comfortably. Therefore, I'll suggest that any airplane can be
quite safely operated with neither voltmeter or ammeter on the
panel.
When you get on the ground, a voltmeter or ammeter on the panel
will only serve to confirm what you already know . . . the alternator
is down for some reason. The most useful troubleshooting voltmeter
is one that measures FIELD voltage on an externally excited
alternator. If you install this capability, wire it like the
VLM-14 system we used to sell, you can diagnose your system
per paragraph 7.0 of
http://216.55.140.222/temp/9021704F.pdf
and KNOW what you need to replace before you pull the cowl
off the airplane.
Now, if you have a handy hole in the panel just dying to be
filled with something, perhaps a voltmeter (analog preferred)
with a push-button switch-over to read field voltage would have
the greatest overall utility in ownership and repair of
your airplane. But maybe that 2-1/4" hole would have more
usefulness if you stuffed a 760VHF transceiver in it.
Some will argue long and hard about the virtues of voltmeters,
loadmeters and -0+ battery ammeters . . . all of these things
are fine instruments that have some degree (but never enough)
utility in troubleshooting your airplane . . . none of these
helps you fly the airplane in the most logical manner. Even
a voltmeter on the e-bus to serve as "battery gas gage"
will only serve to tell you something you probably already
know . . . whether or not you've paid attention to battery
maintenance homework.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
>
>
>I understand don't solve a problem that isn't there. Thats not exactly
>what I was asking. What I was trying to understand is which one do you
>consider to be a better filter?
Oh, sorry . . .
the multi-component filter has the highest noise attenuation
but adds more parts. I'd approach the problem empirically.
First, make SURE the noise isn't getting in through a ground
loop. Then decide if it's better to filter it out of the
victim's 14v supply or to filter at the strobe. Try a fat-cap
at the strobe and see if that's enough. If not, go for the
whole enchilada.
Bob . . .
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: volts vs amps |
In a message dated 5/12/03 1:32:06 PM Central Daylight Time,
kycshann(at)kyol.net writes:
> Not really necessary, but I think it might prove
> useful in diagnosis. What do you think?
>
Sounds fair to me!
Happy Skies,
Old Bob
________________________________________________________________________________
| From: | "Jim Pack" <jpack(at)igs3.com> |
Does it matter where on the buss you read the voltage? If I just hook it up
to one of the fuses on the fuse bus panel, with that work?
> . . . now, if you want something
> to watch and worry about during plan-b operations, you need a
> voltmeter on the e-bus.
________________________________________________________________________________
| Subject: | Re: Circuit protection question follow on |
Bob,
>
> Understand . . . and this is precisely the reason that the
> folks who are supplying this system to you should take the time
> to
Yeah, they should...That's the reason why I'm NOT wiring the plane their
way.
> 4 motors in a flap system? Why? How are they synchronized
> with each other?
Two motors on a single shaft on each side. The two pairs are synchronised by
a "cog belt" (I don't know the exact term) not unlike a small timing belt,
that runs across the fuselage.
>
> Is there a website that describes this system?
Not sure but I can send you photos.
>
then you should write POH
> procedures that call for NOT extending flaps beyond
> comfortable go-around settings until on VERY short final.
Yes, but we also consider having to go around at the last moment.
>
>
> Your friend is worrying about the wrong thing. If
> the flap system can EVER fail in ANY way, then you
> need to operate the airplane in a manner that mitigates
> risk.
Yes, but the go around issue...
Remember, all other things held constant, system
> reliability is inversely proportional to system
> parts count; with 4 motors, your are 4x more likely to have
> a system failure than with one motor. Wire and
> fuse size are WAY down on the list of concerns.
Would I ask here if I really trusted them about electric systems ?
>
> Will failure of a single motor produce asymmetrical
> flap extension? > >
Failure of one motor, no, but the failure of the sync belt definitely WILL
.............
.............
Thermal devices like fuses
> are much slower, breakers slower still, limiters like
> the ANL devices recommended for alternators are virtual
> snails with respect to response time.
>
There we are : ATO fuses are faster than the breaker, and I was concerned
they might blow when the breaker won't. So what about a fuselink ?
>
> I would encourage you to forward a copy of this
> note to the supplier of your flap system. If they
> perceive it to be the helpful suggestion it is
> intended to be, they'll take time to learn more
> about operational details of their product.
>
Not sure they'll find it usefull. My opinion is many people around are
electrically challenged, and they're be puzzled at my questions.
Is this the ONLY option you have for flap
> system operation?
Hmm, yes unless we totally redesign the flap actuation. I asked here last
year when we were making decisions. This is a two man project, and we
settled on keeping the actuators and command box but wiring and protecting
the Connection way.
If it were me I'd use a Cessna type lever with industrial actuators.
Regards,
Gilles
________________________________________________________________________________
| From: | "David Swartzendruber" <dswartzendruber(at)earthlink.net> |
| Subject: | Microprocessor based Fuel Gauge Linearizer |
At the end of last year, there was some discussion about the possibility of
designing a black box that would take the signal from a fuel level sensor,
and provide a corrected signal to the fuel level indicator to make it more
accurate.
At the time, I volunteered to take on this project. In the following
months, I have found that my workload at work and outside of work has
increased rather than decrease as I had hoped. As a result, I am going to
have to back out of fuel gauge linearizer project. Eric Jones had mentioned
the possibility of designing a product for this application. Perhaps he or
someone else could be persuaded to take this on if there is still an
interest in it.
Dave in Wichita
________________________________________________________________________________
| From: | "Shaun Simpkins" <shauns(at)hevanet.com> |
| Subject: | Re: Z13 and Dual Electronic Ignitions |
Aeroelectric-List: Re: Z-13 and Dual Electronic IgnitionsI noted that in Bob's
Z-14 schematic, the battery and alternator field are on the same switch,
sequentially activated. On others, they're separate, according to tradition.
From which I
infer that there's no good reason to have the alternator on WITHOUT the battery.
Then I look
at the Cirrus schematic again ( sorry, all, but I'm fixated on this since Cirrus
is offering itself
up as ultra-safety conscious ) and it has separate battery and alternator field
switches.
The POH notes that the alternators are "self-exciting" and can be run without the
battery,
but not "self-starting" so the battery needs to be connected to restart the engine
in flight.
Now, everything I've read on this list, including the recent thread involving PM
alternators (see
snippet below),
warns me that operating an alternator without a battery as filter is bad. Yet
here is Cirrus
with a system mode that would seem to cause only trouble and confusion ( They also
have
kept the traditional mag/starter key switch ).
Is the Cirrus "self-exciting" alternator a PM design, and why would Cirrus consider
alternator-only
operation a useful configuration?
Shaun
Some regulators (including the B&C regulator
for the SD-8/200G series alternators) won't allow the alternator
to come on line without a battery. I'm not certain of the rational
for this design but I would guess that it's a recognition of the
single phase, pm alternator's really ratty output. There are some
more modern, 3-phase designs available now. I have no personal
experience with them. But don't go on faith that because the
alternator has no need of field excitation that it will automatically
be available and useable sans battery.
If you have only one alternator drive, then I'd stay with the modern
fielded alternator . . . especially an ND. - Bob
________________________________________________________________________________
| From: | "John Karnes" <jpkarnes(at)charter.net> |
| Subject: | Re: OV circuit breaker tripping |
> >Bob,
> > After a new ov module (yellow lead) and new (rebuilt) alternator,
the
> >OV circuit breaker continues to trip right after the engine starts. My
> >plane is wired per Z-2, only I have an auto type ignition instead of
> >magnetos. Please help...I'm desperate. I am about to tear everything
out
> >and start from scratch...
>
> Are you sure you don't have an ov condition? Do you have a voltmeter
> in the airplane? Try disconnecting the ov module, turn off all radios,
> start engine with alternator switch OFF and engine at ramp idle.
> With then turn on all heavy loads like landing lights, taxi lights,
> pitot heat, and THEN turn on alternator while watching the voltmeter.
> If it goes above 15 volts, under these conditions, you have a problem
> with the alternator . . shut down immediately. If it doesn't go above
> 15 volts, then increase RPM to about 2000 while watching voltmeter.
> Again, if it goes above 15 volts, you've got an alternator problem -
> shut down immediately. If the voltage is still okay, start switching
> off the loads one at a time while watching voltmeter. If you get down
to
> no loads and the bus voltage is still normal (13.8 to 14.6 volts) then
> we've confirmed that the alternator is okay.
>
> Do you have the alternator ON while cranking or do you turn it on
> after the engine is running?
Bob-
After disconnecting the ov module and doing the above, the circuit breaker
stays in for about 8 seconds and then trips. Interestingly, when the
circuit breaker is in, the voltmeter only reads 12.0 volts. Do you have any
idea what could be wrong? As I said originally, the alternator is a brand
new, out of the box, internally regulated 12V variety.
John Karnes
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Z13 and Dual Electronic Ignitions |
>
>Aeroelectric-List: Re: Z-13 and Dual Electronic IgnitionsI noted that in
>Bob's Z-14 schematic, the battery and alternator field are on the same switch,
>sequentially activated. On others, they're separate, according to
>tradition. From which I
>infer that there's no good reason to have the alternator on WITHOUT the
>battery. Then I look
>at the Cirrus schematic again ( sorry, all, but I'm fixated on this since
>Cirrus is offering itself
>up as ultra-safety conscious ) and it has separate battery and alternator
>field switches.
I think Bill sent them a copy of Z-14 but they certainly never
bothered to talk with me about it and when Bill complained
about the separate switches, they said they'd tested their
configuration and it was ready to certify. I suspect there
was a Bonanza pilot or two in the design group and whatever
was good for a few thousand Bonanzas couldn't be bad for a
new Cirrus. . .
>The POH notes that the alternators are "self-exciting" and can be run
>without the battery,
>but not "self-starting" so the battery needs to be connected to restart
>the engine in flight.
Restart the "engine" or restart the alternator?
It's been some time since I looked at the power distribution
diagram for Cirrus . . . and I seem to recall that they were
not taking full advantage of everything the modern, light weight
hardware can offer . . .
>Now, everything I've read on this list, including the recent thread
>involving PM alternators (see
>snippet below),
>warns me that operating an alternator without a battery as filter is
>bad. Yet here is Cirrus
>with a system mode that would seem to cause only trouble and confusion (
>They also have
>kept the traditional mag/starter key switch ).
Bonanzas have been offered for over 20 years with alternators
that will both self-excite and therefore, supply useful power
without a battery being on line too. But "useful" power doesn't
mean it's clean power. From a system reliability perspective,
I suppose it was a great step forward in 1980 . . . but we COULD
have been installing e-bus structures and advising owners how
to insure en route power for duration of fuel aboard since that
time as well. We did have a 6A standby generator which was
also self exciting and reasonably clean . . . but had an mean
time between wearout measured in a few hundreds of hours. It
was also a pretty crummy design mechanically . . . but the
best we could offer in 1980. Once certified, it was carved into
stone until B&C came along with 4x the snort and 10x the life
for 2x the dollars.
>Is the Cirrus "self-exciting" alternator a PM design, and why would Cirrus
>consider alternator-only
>operation a useful configuration?
No, I think they're using an SD-20, externally regulated,
wound field alternator. Every alternator will run with some
degree of proficiency sans battery once they're started.
Problem is, a 7x inrush from a landing light or 4x inrush
from a pitot heater might stall a wound field alternator
that doesn't have a battery floated across the line.
It doesn't matter too much if the alternator can start
itself . . . momentary overload would put a big bump in
the bus voltage but you could get the alternator back.
I guess my biggest disappointment with Cirrus is the
lack of understanding about the reliability of modern
battery technologies . . . hmmm . . . maybe that's IT!
They may be selling airplanes with flooded batteries
that cost a lot and they assume the owner is going to
leave it in place for a long time . . . the alternators
may indeed be the most reliable power sources on the
airplane.
At least one of them is a B&C alternator.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: 100 % Solution (diode-fed |
supportbatt-was Avionics bus)
>
>OK, forgot about switching the thing on & off. This extra battery would
>basically function
>as a large, slow discharge capacitor. Why wouldn't an actual capacitor
>tied to the e-bus not
>do the same thing for the short duration of cranking voltage drop? It
>would charge as soon
>as the master were turned on, and maintain some voltage higher than main
>bus voltage when
>cranking (I theorize), not discharging back to the main because of the
>feed diode. This
>seems such an obvious solution that I'm obviously missing the
>obvious! For that matter, why
>wouldn't such a device be a standard installation in all those persnickety
>'lectronic devices
>some manufacturers insist on pampering with an "avionics" bus?
>
>Much of our equipment I work with uses something called a "supercapacitor"
>to maintain data
>during medium duration power outages. Don't know if this sort of thing
>would be useful, or
>how they differ from other capacitors..........
>(my last remaining brain cell seems to be misbehavin'- just slap me & I'll
>shut up)
Not at all. Funny you should mention capacitors. About two years ago
Mallory
was suggesting that some multi-killofarad capacitors they could produce
would
be useful battery replacements in over the road trucks. Kinda cool . . .
but . . . you can get 95% of energy stored in a lead-acid battery over
a discharge voltage range of 10 to 12.5 volts. Since energy stored in
a capacitor is CE(Squared) divided by 2, then a fully charged capacitor
discharged to say, 9 volts, still has over half its energy left when the
terminal voltage drops too low to be useful. One might offset this by
making the capacitor bigger.
Let's assume we need to support a 5A load at or above 9 volts for 10
seconds. 1A load on a 1F capacitor discharges it at 1v/second.
we can tolerate delta volts of 3 x 10 seconds gives us 30 Farads
for 1A load and 150 Farads for 5A load. There are some 1 and 2 Farad
capacitors out there popular with the kilowatt-mobile-gray-matter-
scramblers. They're pretty hefty and run about $100. One might
be able to support just the critical loads on an EFIS system with
less than 5A worth of storage. Maybe a 1 or 2F cap would do it.
It might be worth exploring.
A battery will still store more watt-seconds of energy in less
weight, volume and cost than any other technology we've got
around right now.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: volts vs amps |
>
>Does it matter where on the buss you read the voltage? If I just hook it up
>to one of the fuses on the fuse bus panel, with that work?
yup . . .
Bob . . .
________________________________________________________________________________
| Subject: | Re: Microprocessor based Fuel Gauge Linearizer |
| From: | Jim Ziegler <jcz(at)espllc.com> |
I might be interested, do you have a summary of the requirements?
>
> At the end of last year, there was some discussion about the possibility of
> designing a black box that would take the signal from a fuel level sensor,
> and provide a corrected signal to the fuel level indicator to make it more
> accurate.
>
> At the time, I volunteered to take on this project. In the following
> months, I have found that my workload at work and outside of work has
> increased rather than decrease as I had hoped. As a result, I am going to
> have to back out of fuel gauge linearizer project. Eric Jones had mentioned
> the possibility of designing a product for this application. Perhaps he or
> someone else could be persuaded to take this on if there is still an
> interest in it.
>
> Dave in Wichita
>
>
>
>
>
>
>
--
jcz(at)espllc.com (Jim Ziegler)
________________________________________________________________________________
| From: | "Rob W M Shipley" <Rob(at)RobsGlass.com> |
| Subject: | Yaesu handheld nav/com |
My many thanks to all who offered suggestions when I asked for help a few weeks
ago when trying to identify the TX problem with my handheld.
I'm ashamed to admit that I don't remember who suggested that the battery pack,
(original 3 yr old NiCad), might be the problem.
This was right on the money! I used fresh alkalines in the back up power pack
and checked the TX function against a couple of handhelds and a panel mount whilst
down at SEE this weekend and got a nice nice clear signal.
I've been roaming the web, (Google), looking for a new power pack and found good
prices from the NiCad Lady and Sabah Oceanics. Any input on these sources or
suggestions for other vendors will be appreciated.
Thanks to all who responded. Fly safe.
Rob
Rob W M Shipley
RV9A N919RV Fuselage - now a canoe!!!
________________________________________________________________________________
| From: | William Shaffer <shafferaviation(at)yahoo.com> |
| Subject: | Re: Yaesu handheld nav/com |
Try batterys4everything.com for nicad betterys good prices
Rob W M Shipley wrote:--> AeroElectric-List message posted
by: "Rob W M Shipley"
My many thanks to all who offered suggestions when I asked for help a few weeks
ago when trying to identify the TX problem with my handheld.
I'm ashamed to admit that I don't remember who suggested that the battery pack,
(original 3 yr old NiCad), might be the problem.
This was right on the money! I used fresh alkalines in the back up power pack and
checked the TX function against a couple of handhelds and a panel mount whilst
down at SEE this weekend and got a nice nice clear signal.
I've been roaming the web, (Google), looking for a new power pack and found good
prices from the NiCad Lady and Sabah Oceanics. Any input on these sources or
suggestions for other vendors will be appreciated.
Thanks to all who responded. Fly safe.
Rob
Rob W M Shipley
RV9A N919RV Fuselage - now a canoe!!!
---------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Flap system failure modes (Was circuit protection |
issues)
><Gilles.Thesee@ac-grenoble.fr>
>
>Bob,
>
> >
> > Understand . . . and this is precisely the reason that the
> > folks who are supplying this system to you should take the time
> > to
>
>Yeah, they should...That's the reason why I'm NOT wiring the plane their
>way.
>
> > 4 motors in a flap system? Why? How are they synchronized
> > with each other?
>
>Two motors on a single shaft on each side. The two pairs are synchronised by
>a "cog belt" (I don't know the exact term) not unlike a small timing belt,
>that runs across the fuselage.
> >
> > Is there a website that describes this system?
>
>Not sure but I can send you photos.
Giles sent me the following photo:
http://216.55.140.222/temp/flap_drive.jpg
> > then you should write POH
> > procedures that call for NOT extending flaps beyond
> > comfortable go-around settings until on VERY short final.
>
>Yes, but we also consider having to go around at the last moment.
> >
> >
> > Your friend is worrying about the wrong thing. If
> > the flap system can EVER fail in ANY way, then you
> > need to operate the airplane in a manner that mitigates
> > risk.
>
>Yes, but the go around issue...
Just like the 40-degree flaps on early C-150's . . . there
IS a point beyond which there IS NO GO AROUND physically
possible. I.e., when very effective flaps are fully extended,
there will be a time when height above the runway, available
power, and loss of altitude during flap retraction all add up
to certain contact with the ground.
It sounds to me like your airplane has flaps capable of
defining a high-risk envelope that you want to avoid by
NOT extending flaps beyond a value that you can arrest
decent until your comfortable landing is assured. This
has nothing to do with flap extension/retraction reliability.
Suggest you fully explore this with someone very familiar
with your airplane or experienced enough as a test pilot
to help you put bounds on operating conditions.
The J-3 and C-120 didn't have flaps and after I learned
to fly the airplane, I didn't miss them. They are handy
but in most of the flying I did with those airplanes,
missing flaps wasn't even an inconvenience. More airplanes
have been bent due to mis-use of powerful flaps than have
been bent because of a landing attempt where flaps would
have made a difference between success and crunched metal.
> > Remember, all other things held constant, system
> > reliability is inversely proportional to system
> > parts count; with 4 motors, your are 4x more likely to have
> > a system failure than with one motor. Wire and
> > fuse size are WAY down on the list of concerns.
>
>Would I ask here if I really trusted them about electric systems ?
That question is ALWAYS a good one. Eclipse and Premier
have lots of motors in their flap systems. Failure of any
one actuator stops the flaps in that position and holds it.
For the flight system to be fail safe, the airplane must
be capable of climbing at gross with full flaps . . . and
both airplanes can. Therefore, passive failure of the flap
system does not put the airplane into a sweat-producing
condition.
> >
> > Will failure of a single motor produce asymmetrical
> > flap extension? > >
>
>Failure of one motor, no, but the failure of the sync belt definitely WILL
I think I disagree. Looking at the picture you sent I
perceive that the motors drive a common shaft though worm
gear drives. Worm gears are horribly inefficient . . . usually
50% or less. They can produce tremendous mechanical
advantage in one gear-pass . . . that's why they are popular.
Their ability to resist back driving due to horrible efficiency
is sometimes RELIED upon . . .
For example, suppose you had a trim actuator that you didn't
want to drift when aerodynamic forces are trying to back-drive
the mechanism . . . an acme thread actuator cannot be back-driven,
the coefficient of friction of the threads is higher than the
sine of the lead angle of the thread. You can loose the whole
gearbox upstream of the acme and the actuator will stay put.
Worm gears are a bit better, they might allow a working motor to
backdrive a non-working motor but the energy consumed from the
working motor just to overcome total friction loses of the
non-driving motor put system operation in doubt.
I presume that four motors were put into this system because
someone perceived that this much horsepower was needed -OR-
they thought that even if only two motors were needed to
run the flaps, dual motors would give some degree of reliability
enhancement.
I am skeptical that this 4-motor system would still be okay
with one motor inoperative but mechanically free. If one motor
throws a comm bar or winding and locks up, then the system
is definitely in trouble.
I'm concerned about the long cog-belt. Stretch in these
belts is low but it's based on a percentage of total
length. A belt long enough to traverse the width of the
fuselage is in danger of slipping cogs when tied to a
too-slow actuator on one side and driven by two good
motors on the other side with the mechanical advantage
of their worm gear drives. This is a case where the
advantage of worm gear on one side (mechanical
advantage) stacks against the disadvantage of wormgear
on the other (backdriving forces) to put a lot of
force into the belt.
Flap systems on King Airs use flexible drive cable to take
high speed, low torque energy from ONE motor to MULTIPLE
flap actuators. Using a flex cable (or cog belt) to take
low speed, high torque energy across the airplane
(ESPECIALLY when there is a common motor failure mode
that can over-stress the belt) is a design that needs
careful analysis of the failure modes and effects. It
becomes still more important when you have powerful
flaps that force irrevocable tightening of the flight
envelope in dangerous directions.
>Thermal devices like fuses
> > are much slower, breakers slower still, limiters like
> > the ANL devices recommended for alternators are virtual
> > snails with respect to response time.
> >
>There we are : ATO fuses are faster than the breaker, and I was concerned
>they might blow when the breaker won't. So what about a fuselink ?
Let's fully explore whether or not you really
want to put this system into your airplane. Then
let's see if there are some simpler yet practical
approaches to keeping working motors powered and
smoke inside the wires.
I'm convinced that we're just spinning our
wheels on the electrical side until we have
some confidence on how the mechanical side is
going to work and how it behaves when it's
not working.
> >
> > I would encourage you to forward a copy of this
> > note to the supplier of your flap system. If they
> > perceive it to be the helpful suggestion it is
> > intended to be, they'll take time to learn more
> > about operational details of their product.
> >
>Not sure they'll find it usefull. My opinion is many people around are
>electrically challenged, and they're be puzzled at my questions.
Has this system flown? Has it been tested for all
failure modes including passive failure of one motor
and hard failure (locked armature) of one motor?
> > Is this the ONLY option you have for flap
> > system operation?
>
>Hmm, yes unless we totally redesign the flap actuation. I asked here last
>year when we were making decisions. This is a two man project, and we
>settled on keeping the actuators and command box but wiring and protecting
>the Connection way.
>If it were me I'd use a Cessna type lever with industrial actuators.
That bar on the floor for manual flap operation is pretty
hard to beat too. My recommendations for wiring and
protection may indeed keep your wires from catching fire
. . . but given the questions I've cited above, your
biggest concerns may have nothing to do with keeping the
smoke in your wires.
I forget now, which airplane are you building?
Bob . . .
________________________________________________________________________________
| From: | "David Swartzendruber" <dswartzendruber(at)earthlink.net> |
| Subject: | Microprocessor based Fuel Gauge Linearizer |
The requirements are that you can take the signal from anyone's fuel level
sensor, resistive float or capacitive device, and generate a signal out that
the indicator can use to display the correct fuel qty. The microprocessor
based device could use a lookup table stored in it's memory to know what
fuel qty the input signal represented. The device could be programmed by
the owner of the aircraft by some sort of procedure of adding one gallon at
a time and pushing a button or something. This procedure would create the
lookup table in the memory of the device.
I do not have detailed information on what the different signal levels are
that would have to be accommodated, or what the signal to the indicator
would have to be to accommodate existing indicators. I'm sure the builders
on this list who would like such a device would be willing to help gather
this information.
As this list has also discussed, the black box could only correct certain
types of problems in fuel qty indicator systems. Other problems would
remain. For example, if you have a float system and the travel of the float
does not go all the way to empty or full, there's nothing the black box can
do about it.
Dave in Wichita
>
> I might be interested, do you have a summary of the requirements?
>
________________________________________________________________________________
| From: | Charles Brame <charleyb(at)earthlink.net> |
| Subject: | Tach P-lead feed |
As I understand it, a tach feed from a mag P-lead will work regardless
of whether the mag is "On" or "Off." A mag is turned "Off" by grounding
it, so the P-lead connection at the mag should continue to provide tach
info. The only problem (according to the VM-1000 folks) is that there
may be minor erratic tach indications if the mag has an impulse starter.
I'm not flying yet, so I cannot confirm. Maybe Bob can confirm.
Another option is a transducer that fits on the mechanical tach port on
a Lycoming. Van sells the transducer for $60 (part #IE VTACHGEN2) or $67
if you have a vacuum pump (part #IE VTACGEN12.)
Charlie Brame
RV-6A N11CB
San Antonio
> From: Neil Clayton <harvey4(at)earthlink.net>
> Subject: AeroElectric-List: Tach P-lead feed
>
>
> Van's sells in nice electronic analogue tach that I think I'll use, but the
> description says it works off the mag "P" lead.
>
> How would I wire it to take it's feed from both mag P-leads so that I can
> do a mag-drop test at run up time and still get a signal when I switch from
> one mag to the other?
>
> Thanks
> Neil
>
>
>
>
> From: "William Bernard" <billbernard(at)worldnet.att.net>
> Subject: Subject: AeroElectric-List: Tach P-lead feed
>
>
> Neil, I ran my tach from the P-lead by wiring the tach through a SPST On-On switch.
> This way, only one mag was used at a time and the choice was up to the pilot.
> I've also seen this done using a switch with monentary contact for one pole,
> but this makes a mag check a 3 handed operation.
>
> Hope this helps.
>
> Bill
>
>
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: AutoPilot Disconnect |
>
>In october last year a link was provided to an autopilot disconnect
>schematic. The link was:
>
>http://216.55.140.222/temp/AP_Disconnect.pdf
>
>The link is dead, does anyone have a copy of the schematic?
>
>Thanks,
>Jim
The old one was replaced with a simpler version
and posted at:
http://216.55.140.222/temp/AP_Disconnect_B.pdf
Here's a brain teaser for you electro-wienies out there.
Why is a diode across the coil of the relay not only
not needed but would be ineffectual were it included?
Why, if we can hook an autopilot motor of up to 5A
on this disconnect system, an itty-bitty stick-grip
engage/disengage switch good for perhaps 2A is sufficient?
Why can we get by with a 1w resistor when dissipation
in this resistor at 14v is nearly 20 watts?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Tach P-lead feed |
>
>
>As I understand it, a tach feed from a mag P-lead will work regardless
>of whether the mag is "On" or "Off." A mag is turned "Off" by grounding
>it, so the P-lead connection at the mag should continue to provide tach
>info. The only problem (according to the VM-1000 folks) is that there
>may be minor erratic tach indications if the mag has an impulse starter.
Don't think so. A mag driven tach looks for the "low"
voltage mirror image of the spark that appears across OPEN
points of the mag switch. Closed switch, no spark, no signal
to tach.
>I'm not flying yet, so I cannot confirm. Maybe Bob can confirm.
>
>Another option is a transducer that fits on the mechanical tach port on
>a Lycoming. Van sells the transducer for $60 (part #IE VTACHGEN2) or $67
>if you have a vacuum pump (part #IE VTACGEN12.)
This is the very best way to go. Bypass the ignition systems
entirely. I designed tach transducers for the Bonanzas and Barons
when they went to 2" instruments back in the 80's . . . built
a hall effect transducer that screwed right onto the tach drive
fitting of the engine.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
Thought some of you might be interested in seeing
what I'm doing in the shop for RAC right now. Just
pushed this critter out into the yard for painting
this afternoon.
It's a centrifuge capable of putting 30G of linear
acceleration on some of the equipment we're going
to fly in a new super-sonic target (GQM-163) that
flys mach 2+ at 15 feet off the water.
http://216.55.140.222/temp/MVC-650X.JPG
http://216.55.140.222/temp/MVC-651X.JPG
The big bucket holds test articles. The smaller
bucket holds batteries to power article under
test. The battery bucket can be moved along the
beam to coarse balance against the test article.
A table mounts at the center of the beam to
hold control computer and telemetry to take
test signals off the centrifuge and control
signals on.
I used boat trailer 1" wheel bearings I found
at Walmart. Turned a solid aluminum shaft to
mount beam, pass through bearings and accept
rotation torque from 1/2" drill motor underneath.
Drill motor is about 10x oversized for task but
had nice handles that made it easy to incorporate
into the test fixture. It looks like something on
the order of 15 volts DC will spin this rig up to
about 3 revolutions per second to give me 30G in
the big bucket.
The boss priced one of these and was quoted about
$18,000. I think I beat that price by a good margin!
I've got just over $200 in materials and about
40 hours in it.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | John Loram <johnl(at)loram.org> |
| Subject: | AutoPilot Disconnect |
This is fun;
The first thing to know is that the relay's coil (S704-1) has a resistance
of greater than 140 ohms (base on Aeroelectric specs of, "coil current is
under 100 millamps [sic]").
In the 'quiescent' state (no servo motor power) there is no current flowing
through either the coil or the resistor.
In the 'active' state (servo motor is powered) there is 14 volts to the top
of the 10 ohm resistor which flows through the resistor and the relay coil
to ground. This current is sufficient to hold the relay in the active
position, and is 14volts / (10 ohms + 140 ohms) = .092 amps (92 milliamps).
This produces .092ma
2 * 140ohms = 1.18 watts dissipation in the relay (it
will run warm) and .092ma
2 * 10 = 0.08 watts dissipation in the resistor.
During the transition state when the small switch is held in the 'engage'
position, 14 volts is applied directly across the relay coil, pulling the
relay into the 'active' state.
During the transition state when the small switch is held in the 'disengage'
position, the junction between the 10 ohm resistor and the relay coil will
be held at ground. The current (92 milliamps) flowing through the relay coil
will flow through the small switch to ground, and the energy stored in the
relay coil's magnetic field will be dissipated in the coil's resistance.
There will be a brief spike of current (a bit over an amp) from the 10 ohm
resistor through the small switch. This current will stop as soon as the
relay's magnetic field falls to the point where the relay contacts open
(drops out).
(is there a prize????) ;-) -john-
-----Original Message-----
From: Robert L. Nuckolls, III [mailto:bob.nuckolls(at)cox.net]
Subject: Re: AeroElectric-List: AutoPilot Disconnect
>
>In october last year a link was provided to an autopilot disconnect
>schematic. The link was:
>
>http://216.55.140.222/temp/AP_Disconnect.pdf
>
>The link is dead, does anyone have a copy of the schematic?
>
>Thanks,
>Jim
The old one was replaced with a simpler version
and posted at:
http://216.55.140.222/temp/AP_Disconnect_B.pdf
Here's a brain teaser for you electro-wienies out there.
Why is a diode across the coil of the relay not only
not needed but would be ineffectual were it included?
Why, if we can hook an autopilot motor of up to 5A
on this disconnect system, an itty-bitty stick-grip
engage/disengage switch good for perhaps 2A is sufficient?
Why can we get by with a 1w resistor when dissipation
in this resistor at 14v is nearly 20 watts?
Bob . . .
________________________________________________________________________________
| Subject: | Re: my other life |
$200 bucks? Wow Bob. You are definitely earning your keep. Didn't the boss
want a tail rotor on it too? Some of us want you to burn a CD of it dancing
around the yard.
Does it have a name yet? How about the "Rotor Way Reject" J
John P. Marzluf
Columbus, Ohio
Kitfox Outback (out back in the garage)
________________________________________________________________________________
| From: | "Beckman, Rick" <Rick.Beckman(at)atk.com> |
Thought some of you might be interested in seeing
what I'm doing in the shop for RAC right now. Just
pushed this critter out into the yard for painting
this afternoon.
It's a centrifuge capable of putting 30G of linear
acceleration on some of the equipment we're going
to fly in a new super-sonic target (GQM-163) that
flys mach 2+ at 15 feet off the water.
Good job Bob!!!!!
________________________________________________________________________________
| From: | "Alex Peterson" <alexpeterson(at)usjet.net> |
What happens if that sucker hits a bee or a dragonfly at mach 2???
Alex Peterson
>
> Thought some of you might be interested in seeing
> what I'm doing in the shop for RAC right now. Just
> pushed this critter out into the yard for painting
> this afternoon.
>
> It's a centrifuge capable of putting 30G of linear
> acceleration on some of the equipment we're going
> to fly in a new super-sonic target (GQM-163) that
> flys mach 2+ at 15 feet off the water.
>
>
> http://216.55.140.222/temp/MVC-650X.JPG
> http://216.55.140.222/temp/MVC-651X.JPG
________________________________________________________________________________
Bob or anyone else,
I have a question on Bob's shop notes on aircraft mic jack wiring (
<http://www.aeroelectric.com/articles/micjack/micjack.html>
http://www.aeroelectric.com/articles/micjack/micjack.html). I am
installing an Icom A200 comm radio. Pin 9 is the PTT switch; the pin is
grounded to activate. The wiring for the Microair that Bob shows appears
to be similar, and the PTT circuit is wired through the PTT terminal on
the mic jack. My question, what happens at the mic jack/plug? Does the
plug just complete the PTT circuit to ground? If so, would it also work
if the jack/plug was taken out of the circuit? (Ground the PTT pin
without wiring the PTT terminal at the jack.)
Or
Is the circuit needed to activate the headset mic? If so, what activates
the mic when you are just using the intercom function?
Mark Nielsen
RV-6; 812 hrs.
________________________________________________________________________________
| From: | "Rick Caldwell" <racaldwell(at)hotmail.com> |
| Subject: | Re: Mic Jack Wiring |
Mark,
This is the "normal" way to wire the PTT. However, you do not need to wire
it to the mic jack. But if you bypass it & go directly to the PTT switch,
you can not use the portable PTT switch that plugs into the mic jack. The
mic itself does not need this wired up.
Rick Caldwell
RV-6 & One Design
>
>I have a question on Bob's shop notes on aircraft mic jack wiring (
><http://www.aeroelectric.com/articles/micjack/micjack.html>
>http://www.aeroelectric.com/articles/micjack/micjack.html). I am
>installing an Icom A200 comm radio. Pin 9 is the PTT switch; the pin is
>grounded to activate. The wiring for the Microair that Bob shows appears
>to be similar, and the PTT circuit is wired through the PTT terminal on
>the mic jack. My question, what happens at the mic jack/plug? Does the
>plug just complete the PTT circuit to ground? If so, would it also work
>if the jack/plug was taken out of the circuit? (Ground the PTT pin
>without wiring the PTT terminal at the jack.)
>
>Or
>
>Is the circuit needed to activate the headset mic? If so, what activates
>the mic when you are just using the intercom function?
>
>Mark Nielsen
>
>RV-6; 812 hrs.
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: my other life |
>
>
>What I want to know is where on Earth did you find the time?
>Scott
It's part of my job. The 40 hours I put into it
have been spread out over several months. I also
built a drop tower for shock testing these same
pieces of equipment. By doing these tasks in my
shop at home, I can nudge them along much more
efficiently than if I had them built at RAC. For
one thing, there are no drawings for these pieces
of test equipment. To make a set of drawings from
which someone else would build it might take
40 hours of overhead time just to make the drawings,
get them checked and run through the release system.
Then, if something didn't work out, the person
building the fixture cannot make any changes to
the design until revised drawings are released.
By designing on the fly, I could take advantage
of parts I found in hardware stores and make
instant changes when things didn't come together
as originally envisioned. RAC could have built
it in-house but I suspect they would have invested
about 2x the person-hours. As it stands now, RAC's
total investment is about $3200.
Bob . . .
________________________________________________________________________________
| From: | "Dennis O'Connor" <doconnor(at)chartermi.net> |
| Subject: | Re: my other life |
Just a word to the wise, Bob...
Will it work if nothing goes wrong? - Probably... But in my wasted youth I
was around all kinds of machinery and to my eye you need a harness attached
to that upper bearing block with four cables running out to ground anchors,
and the base firmly anchored also... Also, the lower end of the shaft needs
to be longer and set into another bearing or sleeve as the current setup
will twist itself out of the plywood box if the brown stuff hits the
fan...... You can use belt pulleys to run the drill motor from the side of
the shaft... The other thing you need to plan for is containment of a part
flying off... A battery makes a pretty good missile when flung off a 180 rpm
Trebouchet...
The slightest problem, such as the load slipping, a bearing seizing, a
squirrel trying to dive through, etc. will turn that thing into a flail
mower... You just never know with open frame, rotating machinery...
Denny
ya, ya, ya, I know - I'm just an old worry wart...
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
Subject: AeroElectric-List: my other life
>
> Thought some of you might be interested in seeing
> what I'm doing in the shop for RAC right now. Just
> pushed this critter out into the yard for painting
> this afternoon.
>
> It's a centrifuge capable of putting 30G of linear
> acceleration on some of the equipment we're going
> to fly in a new super-sonic target (GQM-163) that
> flys mach 2+ at 15 feet off the water.
>
>
> http://216.55.140.222/temp/MVC-650X.JPG
> http://216.55.140.222/temp/MVC-651X.JPG
>
> The big bucket holds test articles. The smaller
> bucket holds batteries to power article under
> test. The battery bucket can be moved along the
> beam to coarse balance against the test article.
>
> A table mounts at the center of the beam to
> hold control computer and telemetry to take
> test signals off the centrifuge and control
> signals on.
>
> I used boat trailer 1" wheel bearings I found
> at Walmart. Turned a solid aluminum shaft to
> mount beam, pass through bearings and accept
> rotation torque from 1/2" drill motor underneath.
>
> Drill motor is about 10x oversized for task but
> had nice handles that made it easy to incorporate
> into the test fixture. It looks like something on
> the order of 15 volts DC will spin this rig up to
> about 3 revolutions per second to give me 30G in
> the big bucket.
>
> The boss priced one of these and was quoted about
> $18,000. I think I beat that price by a good margin!
> I've got just over $200 in materials and about
> 40 hours in it.
>
>
> Bob . . .
>
> --------------------------------------------
> ( Knowing about a thing is different than )
> ( understanding it. One can know a lot )
> ( and still understand nothing. )
> ( C.F. Kettering )
> --------------------------------------------
>
>
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
| Subject: | AutoPilot Disconnect |
The diode will be ineffectual because of the latch in resistor. This
resistor will provide a means of dissipating the coils field current.
Assuming the coil of the s704-1 is about 150 ohms, based on your
statement of less than 100ma to engage, we get 150+10, or 160 ohms
resistance from 14V to ground (once the engage switch is pressed). This
computes to 87.5mA of current flow, hence a 2A switch is more than
enough. The engage current is less than 100mA per the specs of the
s704-1. The disengage current will be 14/10, or 1.4A, still within 2A.
We can get by with the 1W resistor due to the current limiting of the
coil resistance to under 100mA (~150 ohms). Adding the 10ohm resistor
lowers the current further to about 87.5mA. The power dissipated in the
resistor is I
2*R, or 87.5mA
2*10= 0.076W, well under the 1W rating.
---
Shannon Knoepflein <---> kycshann(at)kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server(at)matronics.com
[mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of
Robert L. Nuckolls, III
Subject: Re: AeroElectric-List: AutoPilot Disconnect
>
>In october last year a link was provided to an autopilot disconnect
>schematic. The link was:
>
>http://216.55.140.222/temp/AP_Disconnect.pdf
>
>The link is dead, does anyone have a copy of the schematic?
>
>Thanks,
>Jim
The old one was replaced with a simpler version
and posted at:
http://216.55.140.222/temp/AP_Disconnect_B.pdf
Here's a brain teaser for you electro-wienies out there.
Why is a diode across the coil of the relay not only
not needed but would be ineffectual were it included?
Why, if we can hook an autopilot motor of up to 5A
on this disconnect system, an itty-bitty stick-grip
engage/disengage switch good for perhaps 2A is sufficient?
Why can we get by with a 1w resistor when dissipation
in this resistor at 14v is nearly 20 watts?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: my other life |
>
>$200 bucks? Wow Bob. You are definitely earning your keep. Didn't the boss
>want a tail rotor on it too? Some of us want you to burn a CD of it dancing
>around the yard.
>
>Does it have a name yet? How about the "Rotor Way Reject" J
. . . that's a good one.
Dee's favorite color is purple. I suggested we could
name it the "Rolling Purple Parts Eater". But alas,
I'm almost finished painting it the relatively standard
shop-tool gray.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | AutoPilot Disconnect |
>
>This is fun;
>
>The first thing to know is that the relay's coil (S704-1) has a resistance
>of greater than 140 ohms (base on Aeroelectric specs of, "coil current is
>under 100 millamps [sic]").
yes
>In the 'quiescent' state (no servo motor power) there is no current flowing
>through either the coil or the resistor.
yes
>In the 'active' state (servo motor is powered) there is 14 volts to the top
>of the 10 ohm resistor which flows through the resistor and the relay coil
>to ground. This current is sufficient to hold the relay in the active
>position, and is 14volts / (10 ohms + 140 ohms) = .092 amps (92 milliamps).
>This produces .092ma
>2 * 140ohms = 1.18 watts dissipation in the relay (it
>will run warm) and .092ma
>2 * 10 = 0.08 watts dissipation in the resistor.
yes
>During the transition state when the small switch is held in the 'engage'
>position, 14 volts is applied directly across the relay coil, pulling the
>relay into the 'active' state.
yes, but assume you have a 5A load (2.5 ohms) load (servo
motor) what is dissipation in resistor at time of engage switch
closure and how long does it last?
>During the transition state when the small switch is held in the 'disengage'
>position, the junction between the 10 ohm resistor and the relay coil will
>be held at ground. The current (92 milliamps) flowing through the relay coil
>will flow through the small switch to ground, and the energy stored in the
>relay coil's magnetic field will be dissipated in the coil's resistance.
>There will be a brief spike of current (a bit over an amp) from the 10 ohm
>resistor through the small switch. This current will stop as soon as the
>relay's magnetic field falls to the point where the relay contacts open
>(drops out).
Okay, what is the dissipation in resistor at time of
dis-engage switch closure and how long does it last?
What is dissipation mode for energy stored in the
relay coil?
>(is there a prize????) ;-) -john-
Sure, after you finish the test . . .
Bob . . .
________________________________________________________________________________
| From: | BobsV35B(at)aol.com |
| Subject: | Re: my other life |
In a message dated 5/13/03 8:19:43 AM Central Daylight Time,
doconnor(at)chartermi.net writes:
> The slightest problem, such as the load slipping, a bearing seizing, a
> squirrel trying to dive through, etc. will turn that thing into a flail
> mower... You just never know with open frame, rotating machinery...
>
> Denny
>
>
Good Morning Denny,
Or you just put the whole shebang inside a suitable containment vessel, and
let 'er rip!
Happy Skies,
Old Bob
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: my other life |
>
>
>Just a word to the wise, Bob...
>Will it work if nothing goes wrong? - Probably... But in my wasted youth I
>was around all kinds of machinery and to my eye you need a harness attached
>to that upper bearing block with four cables running out to ground anchors,
>and the base firmly anchored also... Also, the lower end of the shaft needs
>to be longer and set into another bearing or sleeve as the current setup
>will twist itself out of the plywood box
There are bearings at both ends of the shaft, top and bottom
of the bearing box.
> if the brown stuff hits the
>fan...... You can use belt pulleys to run the drill motor from the side of
>the shaft... The other thing you need to plan for is containment of a part
>flying off... A battery makes a pretty good missile when flung off a 180 rpm
>Trebouchet...
All good points. Keep in mind that for this thing to function
with any degree of civility, it has to be carefully balanced.
We have knife edge balance points at the center of the shaft
flange. Everything on the moving frame has to be held down
with hardware appropriate to the forces. Test articles and
batteries are in the buckets . . . the batteries cannot move
and test articles can't go very far . . . but even these are
fastened in on brackets and hardware good for several times
expected loads. Beam unbalance will be less than 0.1 oz-in.
The beam and buckets are designed for stiffness.
The I-beam is 5 x 5 with 5/16" webs. Friction at the
bearings is quite low. You cannot touch the beam at
the end lightly enough to keep it from rotating
away from you. Acceleration forces will be so low
for both increasing and decreasing speed that the base
can sit in caster-cups.
Buckets are 1/8" alum sheet riveted together with 1/8" angle
at the corners. Force needed to seriously deflect these shapes is
over 4,000 pounds.
>The slightest problem, such as the load slipping, a bearing seizing, a
>squirrel trying to dive through, etc. will turn that thing into a flail
>mower... You just never know with open frame, rotating machinery...
Yup, we've been doing this stuff for years. Just not
on this scale. I had to build this fixture 'cause our
existing rate table will only handle articles up to 2 pounds
or so.
We've studied and learned the need for robustness and
attention to details. Even so, no person will be in
the room with this thing operating. All the computer and
control equipment needed to conduct the operation will
be in zero-G land on a shelf in the center. Command and
monitoring will be done by radio so we can set in the
next room and know what's happening.
Aside from weight (about 80#) and g-forces (#350 lb
max), forces in the rest of the system are very
low.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Mic Jack Wiring |
><mark.nielsen@fiedler-lp.com>
>
>Bob or anyone else,
>
>I have a question on Bob's shop notes on aircraft mic jack wiring (
><http://www.aeroelectric.com/articles/micjack/micjack.html>
>http://www.aeroelectric.com/articles/micjack/micjack.html). I am
>installing an Icom A200 comm radio. Pin 9 is the PTT switch; the pin is
>grounded to activate. The wiring for the Microair that Bob shows appears
>to be similar, and the PTT circuit is wired through the PTT terminal on
>the mic jack. My question, what happens at the mic jack/plug? Does the
>plug just complete the PTT circuit to ground?
yes
> If so, would it also work
>if the jack/plug was taken out of the circuit? (Ground the PTT pin
>without wiring the PTT terminal at the jack.)
>
>Or
>
>Is the circuit needed to activate the headset mic? If so, what activates
>the mic when you are just using the intercom function?
no, you can totally remote the ptt wiring. HOWEVER,
it is my personal preference to always wire the mic
jack so that the transmitter will function with
any standard aviation microphone plugged in. I carry
a standard hand mic just in case something comes unhooked
in my headset or other parts of ship's wiring.
Bob . . .
________________________________________________________________________________
| From: | "Vincent Welch" <welchvincent(at)hotmail.com> |
| Subject: | Re: Tach P-lead feed |
I have an EIS4000 and would like to go this route. I called Grand Rapids
and Greg is out for a week and the lady that answered the phone has no idea
what I am talking about. I am using one impulse coupled mag and one
Lightspeed ignition.
Have any of you guys hooked up the EIS with Van's tach transducer, and if
so, would you mind sharing your methods?
Thanks
Vince Welch
>From: "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net>
>Reply-To: aeroelectric-list(at)matronics.com
>To: aeroelectric-list(at)matronics.com
>Subject: Re: AeroElectric-List: Tach P-lead feed
>Date: Mon, 12 May 2003 23:41:16 -0500
>
>
>
> >
> >
> >As I understand it, a tach feed from a mag P-lead will work regardless
> >of whether the mag is "On" or "Off." A mag is turned "Off" by grounding
> >it, so the P-lead connection at the mag should continue to provide tach
> >info. The only problem (according to the VM-1000 folks) is that there
> >may be minor erratic tach indications if the mag has an impulse starter.
>
> Don't think so. A mag driven tach looks for the "low"
> voltage mirror image of the spark that appears across OPEN
> points of the mag switch. Closed switch, no spark, no signal
> to tach.
>
>
> >I'm not flying yet, so I cannot confirm. Maybe Bob can confirm.
> >
> >Another option is a transducer that fits on the mechanical tach port on
> >a Lycoming. Van sells the transducer for $60 (part #IE VTACHGEN2) or $67
> >if you have a vacuum pump (part #IE VTACGEN12.)
>
> This is the very best way to go. Bypass the ignition systems
> entirely. I designed tach transducers for the Bonanzas and Barons
> when they went to 2" instruments back in the 80's . . . built
> a hall effect transducer that screwed right onto the tach drive
> fitting of the engine.
>
> Bob . . .
>
>
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | AutoPilot Disconnect |
>
>
>The diode will be ineffectual because of the latch in resistor. This
>resistor will provide a means of dissipating the coils field current.
that's true if the field collapse current flows through the
resistor . . . but consider that during relay drop-out, there's
a dead short across it through the dis-engage switch.
>Assuming the coil of the s704-1 is about 150 ohms, based on your
>statement of less than 100ma to engage, we get 150+10, or 160 ohms
>resistance from 14V to ground (once the engage switch is pressed). This
>computes to 87.5mA of current flow, hence a 2A switch is more than
>enough. The engage current is less than 100mA per the specs of the
>s704-1. The disengage current will be 14/10, or 1.4A, still within 2A.
>
>
>We can get by with the 1W resistor due to the current limiting of the
>coil resistance to under 100mA (~150 ohms). Adding the 10ohm resistor
>lowers the current further to about 87.5mA. The power dissipated in the
>resistor is I
>2*R, or 87.5mA
>2*10= 0.076W, well under the 1W rating.
Actually, power limiting in the resistor is more a function
of the TIME that major currents flow. During engage, resistor
current flows for the 5 milliseconds of relay pull-in time,
and 2 milliseconds or so of drop-out time during dis-engage.
So actually, a 1/2w resistor would work nicely too.
There's another simple circuit that uses an SCR as the
latching device such that the engage/disengage switch
never sees load current . . . but this circuit needs
more parts too.
I was thumbing through an old notebook and found this
idea recorded from a project I worked on quite some time
ago. It was so much simpler than the diagram I published
last year, I decided to update the published drawing.
By the way, one can make this a multi-pole relay and
run trim motors through their own circuits as well. This
is what would be done on an airplane like a bizjet. One
button disconnects all motors that drive flight surfaces.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: OV circuit breaker tripping |
>
>Bob-
>After disconnecting the ov module and doing the above, the circuit breaker
>stays in for about 8 seconds and then trips. Interestingly, when the
>circuit breaker is in, the voltmeter only reads 12.0 volts. Do you have any
>idea what could be wrong? As I said originally, the alternator is a brand
>new, out of the box, internally regulated 12V variety.
>
>John Karnes
Has this system ever worked for a period of time? I presume
that you're doing this test with the engine running and the
constant indication of 12v suggests that the alternator is
not becoming active at any level. I'd check over the wiring.
Try closing the alternator control switch with the engine not
running. You should hear the alternator disconnect contactor
operate and the breaker should stay in.
Sounds like a possible wiring problem.
Bob . . .
________________________________________________________________________________
| From: | "Phil Birkelbach" <phil(at)petrasoft.net> |
| Subject: | Re: Flap system failure modes (Was circuit protection |
issues)
> Giles sent me the following photo:
> http://216.55.140.222/temp/flap_drive.jpg
>
> Let's fully explore whether or not you really
> want to put this system into your airplane. Then
> let's see if there are some simpler yet practical
> approaches to keeping working motors powered and
> smoke inside the wires.
>
> I'm convinced that we're just spinning our
> wheels on the electrical side until we have
> some confidence on how the mechanical side is
> going to work and how it behaves when it's
> not working.
>
I have to agree with Bob. I think that I would SERIOUSLY explore the
reasons why there are four motors in this system. It will NOT increase the
reliability of this system. Especially with the worm gears. I suspect that
those worm gears have a fairly high turn down and the higher the turn down
on a worm gear the higher the braking action. Try to get one set of these
motors to turn with only one motor wired up. If they won't do it then I'd
send the whole thing back to whomever built it and design/buy a system that
uses one motor.
There may be a ratchet type clutch in there somewhere that would allow for
the flaps to at least be retracted once if something broke but then you
would not be able to extend them. Depending on the airplane this may be
acceptable.
Get us some more information about this system and what problems were
associated with the design of the system. Did they need more torque? Is
there a space constraint? Did they assume that more motors would be more
reliable? Sometimes in a design of a system like this there are problems
that surface that initiate a solution that unknowingly creates other
problems. It happens to me at work all the time, I get started down a path
to solve one little problem and it is hard to disassociate myself from that
small problem so I don't see the bigger problem that my solution created
until later. This is where a second, third, or fourth set of eyes can
really help.
Godspeed,
Phil Birkelbach
RV7 - 727WB (Reserved)
http://www.myrv7.com
________________________________________________________________________________
| From: | "Shannon Knoepflein" <kycshann(at)kyol.net> |
| Subject: | AutoPilot Disconnect |
Dissipation in resistor at time of disengage is (14-0)/10, or 1.4A, or
19.6W. It lasts about 2ms from your post. However, there is a way to
calculate it based on the R and L values.
There is some time constant. For an RC circuit, its 1/RC. If I recall
correctly, for an RL, it would be L/R. Close? If that's correct, does
the coil have an inductance of about 0.32H, assuming R is 150 + 10=160?
---
Shannon Knoepflein <---> kycshann(at)kyol.net
Okay, what is the dissipation in resistor at time of
dis-engage switch closure and how long does it last?
What is dissipation mode for energy stored in the
relay coil?
>(is there a prize????) ;-) -john-
Sure, after you finish the test . . .
Bob . . .
________________________________________________________________________________
| From: | MikeM <mladejov(at)ced.utah.edu> |
| Subject: | Re: AutoPilot Disconnect Brain Teaser - 05/12/03 |
With reference to:
> http://216.55.140.222/temp/AP_Disconnect_B.pdf
>
> Here's a brain teaser for you electro-wienies out there.
Oh Goody, a pop quiz like the ones I spring on my students!
> Why is a diode across the coil of the relay not only
> not needed but would be ineffectual were it included?
A snubber diode is not required because as the switch is moved
to the "disengage" position, it is shorting the relay coil, and
thereby provides a path for the coil current to continue flowing
while the energy stored in the magnetic field is dissipated in
the coil resistance. The closed switch contact effectively
holds the coil voltage at 0 V, so absent a forward bias, a diode
would do nothing!
> Why, if we can hook an autopilot motor of up to 5A
> on this disconnect system, an itty-bitty stick-grip
> engage/disengage switch good for perhaps 2A is sufficient?
While the switch is held in the "engage" position, the relay
coil resistance limits the current through the switch to
E/R=14/120=0.12A. On "disengage", the peak current is
E/R=14/10=1.4A, but lasts only while the relay magnetic field
collapses and the relay contacts release. If an external current
path is provided (in this case through the switch), a relay like
this typically releases in about 10msec.
> Why can we get by with a 1w resistor when dissipation
> in this resistor at 14v is nearly 20 watts?
Even though the peak instantaneous dissipation in the resistor
is E
2/R=14*14/10=19.6W, the event lasts only for ~10 msec. A 1W
resistor will take 20W for 10msec provided it only happens
occasionally. I'm guessing that a 1/4 or 1/2 W resistor would be
sufficient.
Proff. Mike Mladejovsky, PhDEE (penultimate electro wienie)
Skylane '1MM
Pacer '00Z
________________________________________________________________________________
| From: | John Loram <johnl(at)loram.org> |
| Subject: | AutoPilot Disconnect |
>
>This is fun;
>
>The first thing to know is that the relay's coil (S704-1) has a resistance
>of greater than 140 ohms (base on Aeroelectric specs of, "coil current is
>under 100 millamps [sic]").
yes
>In the 'quiescent' state (no servo motor power) there is no current flowing
>through either the coil or the resistor.
yes
>In the 'active' state (servo motor is powered) there is 14 volts to the top
>of the 10 ohm resistor which flows through the resistor and the relay coil
>to ground. This current is sufficient to hold the relay in the active
>position, and is 14volts / (10 ohms + 140 ohms) = .092 amps (92 milliamps).
>This produces .092ma
>2 * 140ohms = 1.18 watts dissipation in the relay (it
>will run warm) and .092ma
>2 * 10 = 0.08 watts dissipation in the resistor.
yes
>During the transition state when the small switch is held in the 'engage'
>position, 14 volts is applied directly across the relay coil, pulling the
>relay into the 'active' state.
yes, but assume you have a 5A load (2.5 ohms) load (servo
motor) what is dissipation in resistor at time of engage switch
closure and how long does it last?
Yeh, I should have said something about that. At the time I didn't know
anything about the servo motor's electrical characteristics so left the
answer incomplete;
There will be a current surge through the resistor and small switch of
14volts/(1/(1/10+1/2.5)) = 2amps (plus 100 milliamps through the relay coil
or 1.4 watts in the resistor. It will last unit the relay pulls into the
active state (a few milliseconds at worst) at which time the current through
the small switch will drop to 100 milliamps (coil current) until the small
switch is opened.
>During the transition state when the small switch is held in the
'disengage'
>position, the junction between the 10 ohm resistor and the relay coil will
>be held at ground. The current (92 milliamps) flowing through the relay
coil
>will flow through the small switch to ground, and the energy stored in the
>relay coil's magnetic field will be dissipated in the coil's resistance.
>There will be a brief spike of current (a bit over an amp) from the 10 ohm
>resistor through the small switch. This current will stop as soon as the
>relay's magnetic field falls to the point where the relay contacts open
>(drops out).
Okay, what is the dissipation in resistor at time of
dis-engage switch closure and how long does it last?
There will be a brief surge of current through the switch at disengage time
which will be the sum of the current through the resistor (14 volts / 10
ohms = 1.4 amps (19.6watts )(I'm assuming for simplicity that the servo
motor is purely resistive) and the coil current .092 milliamps. The current
through the resistor will continue until the magnetic field in the relay
collapses to the point at which the relay drops out (usually several
milliseconds).
What is dissipation mode for energy stored in the
relay coil?
The energy stored in the relay coil's magnetic field will be dissipated in
the coil's resistance as the current circulates, primarily through the small
switch.
This analysis makes some simplifying assumptions; most importantly that the
switch and relay contacts have zero resistance, and that the only non-purely
resistive component is the relay coil. The calculation of the effect of
these tertiary elements are left to the student.... ;-)
>(is there a prize????) ;-) -john-
Sure, after you finish the test . . .
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: AutoPilot Disconnect Brain Teaser - |
05/12/03
>
>With reference to:
>
> > http://216.55.140.222/temp/AP_Disconnect_B.pdf
> >
> > Here's a brain teaser for you electro-wienies out there.
>
>Oh Goody, a pop quiz like the ones I spring on my students!
>
>Even though the peak instantaneous dissipation in the resistor
>is E
>2/R=14*14/10=19.6W, the event lasts only for ~10 msec. A 1W
>resistor will take 20W for 10msec provided it only happens
>occasionally. I'm guessing that a 1/4 or 1/2 W resistor would be
>sufficient.
>
>Proff. Mike Mladejovsky, PhDEE (penultimate electro wienie)
>Skylane '1MM
>Pacer '00Z
You got it.
If you like good illustrative brain teasers, try these
on the class . . .
Take molecules of water in 1 cc and enlarge to size
of ping-pong ball (assume 1.5" diameter). Spread
them uniformly over surface of contiguous US
(assume) 5.7 x 10
6 square miles. To what depth
will the ping-pong balls cover the United States?
Another eye-opener . . .
Take an array of steel balls 0.001" in diameter
and stack them into 1 cubic inch of volume. How
many balls does it take to fill the cube? What
is the total surface area of all balls contained
in the cube? What is the open (see-through) area
of the space between the balls for any liquid
that passes into one face and out the opposite face?
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | AutoPilot Disconnect |
>
>
>Dissipation in resistor at time of disengage is (14-0)/10, or 1.4A, or
>19.6W. It lasts about 2ms from your post. However, there is a way to
>calculate it based on the R and L values.
>
>There is some time constant. For an RC circuit, its 1/RC. If I recall
>correctly, for an RL, it would be L/R. Close? If that's correct, does
>the coil have an inductance of about 0.32H, assuming R is 150 + 10=160?
You're correct that there are other relationships to consider
but in comparison to the major effects, they are pretty small
and I was neglecting them. The major effects for what the
resistor sees have more to do with Bus, Load and engage/disengage
switch. For example, you could substitute a 160 ohm resistor for
the effects of the relay coil and not significantly
change the outcome of the analysis.
Bob . . .
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | OV runaway in an internally regulated alternator |
>Below is the result of your inquiry. It was submitted by
>Frank Piszkin (fpiszkin(at)thegrid.net) on Tuesday, May 13, 2003 at 11:01:57
>
>Tuesday, May 13, 2003
>
>Frank Piszkin
>
>,
>Email: fpiszkin(at)thegrid.net
>Comments/Questions: I submitted this inquiry a couple of weeks ago but
>have received no response.
>So, again, can you help me understand how the alternator disconnect contactor
>(S701-1) effects a disconnect? My electrical knowledge is barely beyond Ohm's
>Law. Looking at the wiring diagram you provided (for the internal regulator),
>it appears to me that the OVM-14 module is required to drop out the field
>voltage
>to the alternator (and the contactor) and cause the contactor to disconnect.
>But there is a jumper wire on the contactor which would appear to hold in
>the contactor since it provides a path to the battery side. What am I
>misunderstanding?
>And, why is the disconnect contactor required if the OVM-14 would, by itself,
>remove the field voltage from the alternator? Is it just simply to assure
>isolation
>of the aternator from the battery side? Please dumb it down for me, Bob. I
>really do
>want to understand how the system functions before I go wiring things up.
>Thanks, Frank
I think I invited you to join the AeroElectric List
for this conversation. I get lots of requests for one-on-one
tutorials every week and I've got a limited amount
of time to devote to operating the 'Connection. When
you put these questions out on the list, you're more
likely to get a response from me because (1) I've blocked out
most of my time to support the list and (2) the information
is shared with lots of other folks. Moreover, there are
many folks on the list besides me who can do a good job
of answering.
Not trying to be a hard-ass. Further, I very much appreciate
and encourage your desire to understand how the system
works. I firmly belive in the dissemination of knowledge.
But this activity works 1000% better in a forum where
many can benefit both as students and as teachers.
In a nutshell . . . internally regulated alternators
do not get their field excitation current from the
control lead. There are failure modes within an internally
regulated alternator that cannot be overridden by
shutting off the control lead. Hence, the need for
physical and total disconnection of the alternator
from ship's wiring in the event of an overvoltage
event.
Bob . . .
|---------------------------------------------------|
| A lie can travel half way around the world while |
| the truth is till putting on its shoes . . . |
| -Mark Twain- |
|---------------------------------------------------|
________________________________________________________________________________
| From: | "JOHN KARNES" <jpkarnes(at)charter.net> |
| Subject: | Re: OV circuit breaker tripping |
> Has this system ever worked for a period of time? I
>presume
> that you're doing this test with the engine running
>and the
> constant indication of 12v suggests that the
>alternator is
> not becoming active at any level. I'd check over the
>wiring.
> Try closing the alternator control switch with the
>engine not
> running. You should hear the alternator disconnect
>contactor
> operate and the breaker should stay in.
>
> Sounds like a possible wiring problem.
>
> Bob . . .
Bob-
The system worked fine as currently wired until my engine
overheated last summer. The old alternator had bad
diodes, so I thought that was the problem. After
replacing the OV module and alternator, the problem
continues. Why would the circuit breaker trip if there is
only 12V leaving the alternator? When the button is
pushed in on the circuit breaker, there is a small rise in
voltage, albeit only to 12.0 V. If there is a wiring
problem, where would you suggest I look? Thanks for your
help
John Karnes
jpkarnes(at)charter.net
________________________________________________________________________________
| Subject: | Re: Flap system failure modes (Was circuit protection |
issues)
Phil,
>
> I have to agree with Bob. I think that I would SERIOUSLY explore the
> reasons why there are four motors in this system. It will NOT increase
the
> reliability of this system. Especially with the worm gears. I suspect
that
> those worm gears have a fairly high turn down and the higher the turn down
> on a worm gear the higher the braking action. Try to get one set of these
> motors to turn with only one motor wired up. If they won't do it then I'd
> send the whole thing back to whomever built it and design/buy a system
that
> uses one motor.
If it were my airplane, I would'nt even bother to make this experiment : I'd
design something else from the start. But I'm NOT the one who makes the
decisions on that project.
I definitely am the one in charge of making those motors spin as long as
they don't fall apart or weld solid inside, and keeping the smoke inside the
wires.
>
> There may be a ratchet type clutch in there somewhere that would allow for
> the flaps to at least be retracted once if something broke but then you
> would not be able to extend them. Depending on the airplane this may be
> acceptable.
>
> Get us some more information about this system and what problems were
> associated with the design of the system. Did they need more torque?
Sure
Is
> there a space constraint?
No
Did they assume that more motors would be more
> reliable?
Don't think so. Torque. And being acqainted with the motor for already using
it for the pitch trim.
Sometimes in a design of a system like this there are problems
> that surface that initiate a solution that unknowingly creates other
> problems. It happens to me at work all the time, I get started down a
path
> to solve one little problem and it is hard to disassociate myself from
that
> small problem so I don't see the bigger problem that my solution created
> until later. This is where a second, third, or fourth set of eyes can
> really help.
>
See my other mail. thanks for your advice,
Gilles
________________________________________________________________________________
| Subject: | Re: Flap system failure modes (Was circuit protection |
issues)
Hi Bob and all,
> It sounds to me like your airplane has flaps capable of
> defining a high-risk envelope that you want to avoid by
> NOT extending flaps beyond a value that you can arrest
> decent until your comfortable landing is assured. This
> has nothing to do with flap extension/retraction reliability.
> Suggest you fully explore this with someone very familiar
> with your airplane or experienced enough as a test pilot
> to help you put bounds on operating conditions.
>
This has been recognized by the kit manufacturer, who proposes to reduce
flap extension to less drastic values. By the way the test pilot is my
former chief pilot and aerobatics coach.
>
> I think I disagree. Looking at the picture you sent I
> perceive that the motors drive a common shaft though worm
> gear drives. Worm gears are horribly inefficient . . . usually
> 50% or less. They can produce tremendous mechanical
> advantage in one gear-pass . . . that's why they are popular.
> Their ability to resist back driving due to horrible efficiency
> is sometimes RELIED upon . . .
>
....................
>
> I presume that four motors were put into this system because
> someone perceived that this much horsepower was needed -OR-
> they thought that even if only two motors were needed to
> run the flaps, dual motors would give some degree of reliability
> enhancement.
>
> I am skeptical that this 4-motor system would still be okay
> with one motor inoperative but mechanically free. If one motor
> throws a comm bar or winding and locks up, then the system
> is definitely in trouble.
>
................
>
> I'm convinced that we're just spinning our
> wheels on the electrical side until we have
> some confidence on how the mechanical side is
> going to work and how it behaves when it's
> not working.
Please tell me if I understand correctly : the flap system could very well
lock up in case of motor failure. Provided I have to wire the system as is,
I have to make provision for an electrically safe behaviour in this case.
The resettable breaker is out of the question, any resetting could induce
wire overheating, or asymetrical deployment.
> Has this system flown?
The system is flying in about 40 to 50 two seaters and five or so four
seaters. The only failures I'm aware of are smoke under the panel on the
ground, and failure to extend due to loose connections.
Has it been tested for all
> failure modes including passive failure of one motor
> and hard failure (locked armature) of one motor?
>
I guess you and I know too well....
>
> That bar on the floor for manual flap operation is pretty
> hard to beat too. My recommendations for wiring and
> protection may indeed keep your wires from catching fire
> . . . but given the questions I've cited above, your
> biggest concerns may have nothing to do with keeping the
> smoke in your wires.
You're right.
Hand flaps are among the safest. But such a system would entail extensive
mods of the fuselage, console and throttle, wire conduits etc...
Unfortunately the decisions have been made last year, and I'm not in a
position to decide on a major redesign of the mechanical systems. I'm only
in charge of the wiring, but I'm determined to accomplish it as best as I
can, and thanks to your advice, to make it as ELECTRICALLY safe as is
practically possible.
That's why I was thinking of a fuselink to replace the fast acting fuse.
Doable, not doable ?
>
> I forget now, which airplane are you building?
It is an MCR 4S, see
http://www.avnet.co.uk/touchdown/pages/mcr4s.htm
Thanks for all your help.
________________________________________________________________________________
| From: | "Shaun Simpkins" <shauns(at)hevanet.com> |
| Subject: | Re: Z13 and Dual Electronic Ignitions |
>. . . hmmm . . . maybe that's IT!
> [Cirrus] may be selling airplanes with flooded batteries
>that cost a lot and they assume the owner is going to
> leave it in place for a long time .
>Bob . . .
Bob:
Thanks.
I think that's the reason. The prime battery is up front, the secondary
battery is buried behind the rear seat, where the owner will forget about
it until it's too late. The diode connection from the primary to the secondary
alternator system suggests that Cirrus expects the secondary battery to be
forgotten; if it dies, they're counting on the primary system to take over. Which
says
their e-bus is really the primary system, and...ecch.
Shaun
________________________________________________________________________________
| From: | "Cy Galley" <cgalley(at)qcbc.org> |
| Subject: | Re: OV circuit breaker tripping |
Sounds like a dead short.
It would pull down the voltage and the excess amperage would trip the
breaker.
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: "JOHN KARNES" <jpkarnes(at)charter.net>
Subject: Re: AeroElectric-List: OV circuit breaker tripping
>
> > Has this system ever worked for a period of time? I
> >presume
> > that you're doing this test with the engine running
> >and the
> > constant indication of 12v suggests that the
> >alternator is
> > not becoming active at any level. I'd check over the
> >wiring.
> > Try closing the alternator control switch with the
> >engine not
> > running. You should hear the alternator disconnect
> >contactor
> > operate and the breaker should stay in.
> >
> > Sounds like a possible wiring problem.
> >
> > Bob . . .
>
>
> Bob-
> The system worked fine as currently wired until my engine
> overheated last summer. The old alternator had bad
> diodes, so I thought that was the problem. After
> replacing the OV module and alternator, the problem
> continues. Why would the circuit breaker trip if there is
> only 12V leaving the alternator? When the button is
> pushed in on the circuit breaker, there is a small rise in
> voltage, albeit only to 12.0 V. If there is a wiring
> problem, where would you suggest I look? Thanks for your
> help
>
> John Karnes
> jpkarnes(at)charter.net
>
>
________________________________________________________________________________
| From: | "Phil Birkelbach" <phil(at)petrasoft.net> |
| Subject: | Re: AutoPilot Disconnect Brain Teaser - 05/12/03 |
> Take an array of steel balls 0.001" in diameter
> and stack them into 1 cubic inch of volume. How
> many balls does it take to fill the cube? What
> is the total surface area of all balls contained
> in the cube? What is the open (see-through) area
> of the space between the balls for any liquid
> that passes into one face and out the opposite face?
>
> Bob . . .
>
You'll need 1,000
3 steel balls or...
1,000,000,000 balls
The surface area of a sphere is... 4*pi*r
2
So the area of one ball... 3.141592E-6 sq in
So the area of a billion balls... 3,141.5 sq in or 21.8166 sq ft
which is about 2/3 the area of a piece of plywood.
Now for the second part the wetted area...
It would be 1 sq in - the area of a million circles...
area of a circle = pi * r
2
Area of a 0.001" diameter circle = 7.85398E-7 sq in
Area of a million of them would be... 0.785398 sq in
so the see through area would be... 0.214602 sq in
Of course this all assumes that we stack the balls in a rectangular pattern
1,000 balls to an edge, and the 1 cubic inch volume is a 1" x 1" x 1" cube,
if it is anything more sinister than that then I don't have time to look it
up. :-)
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: Flap system failure modes (Was |
circuit protection issues)
><Gilles.Thesee@ac-grenoble.fr>
>
>
>Hi Bob and all,
>
>
> > It sounds to me like your airplane has flaps capable of
> > defining a high-risk envelope that you want to avoid by
> > NOT extending flaps beyond a value that you can arrest
> > decent until your comfortable landing is assured. This
> > has nothing to do with flap extension/retraction reliability.
> > Suggest you fully explore this with someone very familiar
> > with your airplane or experienced enough as a test pilot
> > to help you put bounds on operating conditions.
> >
>
>This has been recognized by the kit manufacturer, who proposes to reduce
>flap extension to less drastic values. By the way the test pilot is my
>former chief pilot and aerobatics coach.
Okay. I'm not sure you need to have an on-purpose limitation
to the flaps as long as your pilots are aware how to use
them safely. Benefits of flaps happen at touchdown. More
flaps just makes you come down faster and leaves you with
less energy to squander in the flare. If I were a flight
instructor, I'd not let a student use flaps at all until
they were proficient without them.
In the older C-150's, you could get the best of both
worlds by hanging out no more drag than you can tolerate
at full throttle to arrest your descent. When you're
sure you have the landing made, put out the rest of
the flaps.
>Please tell me if I understand correctly : the flap system could very well
>lock up in case of motor failure. Provided I have to wire the system as is,
>I have to make provision for an electrically safe behaviour in this case.
>The resettable breaker is out of the question, any resetting could induce
>wire overheating, or asymetrical deployment.
This is a distinct possibility.
> > Has this system flown?
>
>The system is flying in about 40 to 50 two seaters and five or so four
>seaters. The only failures I'm aware of are smoke under the panel on the
>ground, and failure to extend due to loose connections.
>
> > Has it been tested for all
> > failure modes including passive failure of one motor
> > and hard failure (locked armature) of one motor?
> >
>
>I guess you and I know too well....
Okay, let's see what we can do to make failures as tolerant
as possible. I think I'd simply wire all four motors in
parallel with each other. Treat them as a single motor.
Drive the system through a single, 20A breaker at the bus.
The idea of protecting each motor in any way is scary. You
don't want the system to continue to run in any way if one
motor has decided to mis-behave.
My sense is that this little airplane simply cannot need
as much snort as a 20A breaker would suggest. Wire with
14AWG wire and put a 20A breaker in for now. During flight
testing, let's put an ammeter in and see what the system
REALLY needs. I wouldn't be surprised to see that we can
drop the breaker size down to 15 or even 10 amps. An
RV actuator runs at under 5A. You don't need to size the
breaker for inrush currents.
If one wanted to reduce the hazards of single motor
failure, we could design some fancy circuitry to sense
abnormal operation and shut the whole system down
when it was detected.
Single point protection combined with judicious use
of flaps in approach-to-landing should let you make the
best of a rather un-thoughtful design. This wouldn't be
the only airplane flying around with idiosyncrasies
capable of embarrassing you or driving your pucker
factor up. Take a checkout in a Tri-Pacer or a AA-1
Yankee and have the check pilot show you how easy it
is to get tense in these airplanes. They ain't your
grandfather's C-172.
If this system has a satisfactory history . . . meaning
that gear-boxes aren't shelling out and motors are
hanging in there, then you're not facing gross design
limits or high rates of infant mortality. This suggests
that until a motor or gearbox reaches wear-out,
you won't have to shoulder duties as a failure modes
test-pilot soon. Maybe this won't happen until after you've
sold the airplane.
Bob . . .
________________________________________________________________________________
| From: | "nhulin" <nhulin(at)hotmail.com> |
| Subject: | Re: Microprocessor based Fuel Gauge Linearizer |
On Mon May 12 at 7:31 PM Jim Ziegler (jcz(at)espllc.com) wrote:
> I might be interested, do you have a summary of the requirements?
Guys,
Are you trying to solve a problem here that has limitations that you are
unlikely to overcome?
I've just installed the fuel tanks in my Zodiac 601XL and have been testing
the installation of the VDO style float arm resistive senders. The Zodiac
uses tanks of uniform shape but they are installed in a wing with dihedral.
Given that the sender is installed in the lower end of the tank to give the
best empty reading, the size of the float ball, and the dihedral, I found
that for the first few gallons down from full the float ball is pinned to
the top of the tank and no meaningful reading can be expected (except, of
course, "full"). On the low end it is much better but the ball eventually
bottoms before the tank is empty. In the middle it is reasonably linear.
For a very unusually shaped tank the linearizer would be helpful. The cost?
Perhaps a fuel totalizer would provide more benefit in these cases.
Just my 2c.
BTW: I designed a simple LED bargraph fuel gauge that seems to work OK (at
least in prototype form) since I have four tanks and the cost of gauges was
a bit too much. If I'm happy with the design when it is finished I'll let
the Aero'List know.
...neil
Neil Hulin
Zodiac 601XL
Cincinnati Ohio
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: AutoPilot Disconnect Brain Teaser |
-05/12/03
>
>
>"Robert L. Nuckolls, III" wrote:
>
> > -->
> >
> > Another eye-opener . . .
> >
> > Take an array of steel balls 0.001" in diameter
> > and stack them into 1 cubic inch of volume. How
> > many balls does it take to fill the cube? What
> > is the total surface area of all balls contained
> > in the cube? What is the open (see-through) area
> > of the space between the balls for any liquid
> > that passes into one face and out the opposite face?
> >
> > Bob . . .
> >
>
>1,000,000,000 balls (1 billion)
yes
>2,000,000 square inches (.318845 acres)
??????
>.21461 square inches of open area (just shy of 1/4 of the total area)
yes
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: AutoPilot Disconnect Brain Teaser - |
05/12/03
>
>
> > Take an array of steel balls 0.001" in diameter
> > and stack them into 1 cubic inch of volume. How
> > many balls does it take to fill the cube? What
> > is the total surface area of all balls contained
> > in the cube? What is the open (see-through) area
> > of the space between the balls for any liquid
> > that passes into one face and out the opposite face?
> >
> > Bob . . .
> >
>You'll need 1,000
3 steel balls or...
>
>1,000,000,000 balls
>
>The surface area of a sphere is... 4*pi*r
2
>
>So the area of one ball... 3.141592E-6 sq in
>So the area of a billion balls... 3,141.5 sq in or 21.8166 sq ft
>which is about 2/3 the area of a piece of plywood.
That's the part that really surprises folks . . . that
a 1" cube could have that much surface area contained
within.
>Now for the second part the wetted area...
>
>It would be 1 sq in - the area of a million circles...
>
>area of a circle = pi * r
2
>
>Area of a 0.001" diameter circle = 7.85398E-7 sq in
>Area of a million of them would be... 0.785398 sq in
>so the see through area would be... 0.214602 sq in
yup . . .
>Of course this all assumes that we stack the balls in a rectangular pattern
>1,000 balls to an edge, and the 1 cubic inch volume is a 1" x 1" x 1" cube,
>if it is anything more sinister than that then I don't have time to look it
>up. :-)
yeah, getting all those balls to set in there un-nested
takes some REAL patience.
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
________________________________________________________________________________
| From: | "Robert L. Nuckolls, III" <bob.nuckolls(at)cox.net> |
| Subject: | Re: OV circuit breaker tripping |
May 06, 2003 - May 13, 2003
AeroElectric-Archive.digest.vol-bz