Today's Message Index:
----------------------
1. 03:56 AM - Re: Tire valve extension (rd2@evenlink.com)
2. 05:10 AM - flap control Cessna (Hoffmann D- Remscheid)
3. 05:13 AM - LED - flashing beacon (Hoffmann D- Remscheid)
4. 06:26 AM - Re: Tire valve extension (Mark R Steitle)
5. 06:42 AM - Re: Tire valve extension (N5SL)
6. 07:03 AM - Re: Alternator field breaker (Bernard Despins)
7. 07:04 AM - Re: LED - flashing beacon (Lloyd, Daniel R.)
8. 07:09 AM - Re: Tire valve extension (Greg Young)
9. 07:17 AM - Re: Alternator field breaker (BobsV35B@aol.com)
10. 07:25 AM - Re: Tire valve extension (Mark R Steitle)
11. 08:14 AM - Re: Tire valve extension (Mark R Steitle)
12. 08:22 AM - Re: Alternator field breaker (Matt Prather)
13. 09:17 AM - Re: Alternator field breaker (Bernard Despins)
14. 10:29 AM - Re: Alternator field breaker (Kevin Horton)
15. 11:26 AM - Re: Alternator field breaker (Matt Prather)
16. 11:50 AM - Breaker Interrupt Rating (Matt Prather)
17. 12:17 PM - Re: Alternator field breaker (Bernard Despins)
18. 01:58 PM - degaussing (demagnetizing) my roll bar (Mickey Coggins)
19. 02:07 PM - Re: avionics wiring hub (CardinalNSB@aol.com)
20. 03:02 PM - Re: degaussing (demagnetizing) my roll bar (Guy Buchanan)
21. 03:11 PM - Re: degaussing (demagnetizing) my roll bar (LarryRobertHelming)
22. 03:30 PM - Re: Tire valve extension (Robert G. Wright)
23. 03:41 PM - degaussing (demagnetizing) my roll bar (Craig Berland)
24. 06:27 PM - Re: Breaker Interrupt Rating (Eric M. Jones)
25. 06:43 PM - Re: Alternator field breaker (Robert L. Nuckolls, III)
26. 07:29 PM - Re: Re: Breaker Interrupt Rating (Robert L. Nuckolls, III)
27. 07:44 PM - Re: LED - flashing beacon (Bob White)
28. 08:16 PM - Re: degaussing (demagnetizing) my roll bar (GMC)
29. 08:20 PM - Re: Alternator field breaker (Robert L. Nuckolls, III)
30. 08:21 PM - Re: Re: Breaker Interrupt Rating (Matt Prather)
31. 10:37 PM - Re: degaussing (demagnetizing) my roll bar (Mickey Coggins)
32. 10:50 PM - Re: Re: Breaker Interrupt Rating (Mickey Coggins)
Message 1
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Subject: | Re: Tire valve extension |
--> AeroElectric-List message posted by: rd2@evenlink.com
I guess I wasn't paying enough attention - mis-read the initial post to
mean "permanent" extension.
Rumen
do not archive
_____________________Original message __________________________
(received from Dj Merrill; Date: 04:27 PM 9/14/2005
-0400)
--> AeroElectric-List message posted by: Dj Merrill
<deej@thayer.dartmouth.edu>
rd2@evenlink.com wrote:
> Didn't know such thing existed - if the tire has an extensiion exceeding
> the pant, how does it turn ? :)
>
> I've got capped holes on the pants - remove the cap, inflate replace the
> cap. Valves are a bit far and awkward to reach, but doable (would like to
> extend them a bit if sshort extensions are available; the auto ones are too
> long).
>
> Rumen
Hi Rumen,
You temporarily put the extensions on to allow you
to put air in easily, them remove them before moving
the plane. Basically, remove the wheel pant cap, screw on the
extension, check air, remove the extension, and put
the cap back on your wheel pant.
Hope this helps! :-)
-Dj
--
Dj Merrill
Sportsman 2+2 Builder #7118
"Many things that are unexplainable happen during the construction of an
airplane." --Dave Prizio, 30 Aug 2005
"TSA: Totally Screwing Aviation"
--
Message 2
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Subject: | flap control Cessna |
--> AeroElectric-List message posted by: "Hoffmann D- Remscheid" <Hoffmann.RS@t-online.de>
Hello
by following this thread backwards I have found that all my questions concerning
flap control for my homebuilt have in principle already been answered by the
Cessna solution. They use a feedback of the flap position to the panel via mechanical
cable as a simple and ingenious way.
Is there anybody who has done the same thing more recently and could kindly provide
me with some information or drawings, eventually from the Cessna maintenance
manual?
Greetings
Richard
Richard Hoffmann
Am Wiesenhang 45
D-42859 Remscheid
Germany
Message 3
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Subject: | LED - flashing beacon |
--> AeroElectric-List message posted by: "Hoffmann D- Remscheid" <Hoffmann.RS@t-online.de>
Hello,
for my homebuilt I want to build a beacon using these white super LED's, three
in series (3 * 3,5V 10.5V). For 12V systems this seems ideal to me.
The only disadvantage is that you need a constant current source, favourably in
combination with a flashing device. Has anybody done this before? I don't want
to invent the wheel twice (;-)).
Greetings Richard
Message 4
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Subject: | Tire valve extension |
--> AeroElectric-List message posted by: "Mark R Steitle" <mark.steitle@austin.utexas.edu>
Thanks, good suggestion.
Mark
Do not archive
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Bob
McCallum
Subject: Re: AeroElectric-List: Tire valve extension
--> AeroElectric-List message posted by: "Bob McCallum"
<robert.mccallum2@sympatico.ca>
Mark;
Many of the automotive systems are radio transmitters which replace the
valve caps and send a signal to a central monitoring panel. Some are
capable
of monitoring up to 34 tyres. Some give an actual pressure reading,
others
just notify you of a change in pressure greater than some preset value.
There should be no reason why they wouldn't work in an aircraft. A
google
search for "tyre pressure monitors" or "tyre inflation monitors" will
give
hundreds of hits to check out the offerings.
Bob McC
do not archive
----- Original Message -----
From: "Mark R Steitle" <mark.steitle@austin.utexas.edu>
> This a bit far out there, but since this is the Aero-Electric list I
> will bring it up anyway. I'm wondering how some vehicles in the the
> auto/motorcycle world manage to monitor tire pressures, and could this
> be easily adapted to OBAM aircraft?
>
> Mark S.
>
>
Message 5
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Subject: | Tire valve extension |
--> AeroElectric-List message posted by: N5SL <nfivesl@yahoo.com>
Good Morning Mark:
Our new jeep has this feature and I found out when I swapped one of the wheels
with the spare after a flat. Here is an interesting article that explains how
it works:
http://www.wjjeeps.com/tpms.htm
Scott Laughlin
www.cooknwithgas.com
601XL / Corvair
Working on Instrument Panel
Mark R Steitle <mark.steitle@austin.utexas.edu> wrote:
I'm wondering how some vehicles in the the
auto/motorcycle world manage to monitor tire pressures, and could this
be easily adapted to OBAM aircraft?
Mark S.
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
Message 6
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Subject: | Re: Alternator field breaker |
--> AeroElectric-List message posted by: Bernard Despins <bdespins@telusplanet.net>
The difficulty I'm having is that in my Velocity XLRG (all electric,
dual everything except propellers), the auxiliary alternator, regulator,
and battery are all in the rear. The auxiliary bus does not come to the
front of the plane. A circuit breaker would not be accessible. Is it
worth running a wire to the front and back and place a circuit breaker
on the panel? I do have a circuit breaker for the main alternator field.
Bernard Despins
Robert L. Nuckolls, III wrote:
> <>So if using the ov protection built into the LR3C from B & C Specialty,
> you would suggest using a circuit breaker instead of a fuse?
>
> Bernard Despins
>
>
> Correct. This is shown on all drawings provided by B&C and by
> the 'Connection where the B&C products are illustrated.
>
> Bob . . .
>
>
Message 7
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Subject: | LED - flashing beacon |
--> AeroElectric-List message posted by: "Lloyd, Daniel R." <LloydDR@wernerco.com>
You can buy the flashing device at
http://www.strobe-direct.com/catalog/Able2Products/led_accessories.htm#1
1.1002 but be warned that flashing LED's might not meet the intensity
requirements.
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
Hoffmann D- Remscheid
Subject: AeroElectric-List: LED - flashing beacon
--> AeroElectric-List message posted by: "Hoffmann D- Remscheid"
<Hoffmann.RS@t-online.de>
Hello,
for my homebuilt I want to build a beacon using these white super LED's,
three in series (3 * 3,5V 10.5V). For 12V systems this seems ideal to
me.
The only disadvantage is that you need a constant current source,
favourably in combination with a flashing device. Has anybody done this
before? I don't want to invent the wheel twice (;-)).
Greetings Richard
Message 8
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|
Subject: | Tire valve extension |
--> AeroElectric-List message posted by: "Greg Young" <gyoung@cs-sol.com>
Interesting - they use the space inside a tubeless tire for the
transmitter. Now we need to find one that works with a tube.
Greg Young
> --> AeroElectric-List message posted by: N5SL <nfivesl@yahoo.com>
>
> Good Morning Mark:
>
> Our new jeep has this feature and I found out when I swapped
> one of the wheels with the spare after a flat. Here is an
> interesting article that explains how it works:
>
> http://www.wjjeeps.com/tpms.htm
>
>
> Scott Laughlin
> www.cooknwithgas.com
> 601XL / Corvair
> Working on Instrument Panel
>
> Mark R Steitle <mark.steitle@austin.utexas.edu> wrote:
> I'm wondering how some vehicles in the the auto/motorcycle
> world manage to monitor tire pressures, and could this be
> easily adapted to OBAM aircraft?
>
> Mark S.
Message 9
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Subject: | Re: Alternator field breaker |
--> AeroElectric-List message posted by: BobsV35B@aol.com
In a message dated 9/15/2005 9:05:42 A.M. Central Standard Time,
bdespins@telusplanet.net writes:
The difficulty I'm having is that in my Velocity XLRG (all electric,
dual everything except propellers), the auxiliary alternator, regulator,
and battery are all in the rear. The auxiliary bus does not come to the
front of the plane. A circuit breaker would not be accessible. Is it
worth running a wire to the front and back and place a circuit breaker
on the panel? I do have a circuit breaker for the main alternator field.
Bernard Despins
Good Morning Bernard,
I am not at all conversant with what you are trying to accomplish, but would
a Remote Control Circuit Breaker be of any use in your application?
The RCCBs found heavy use in the DC-10 and I imagine they are more widely
used today.
The CB could be back where Fat Wires exist with very small wires to the
cockpit for control and indication.
Just a random thought.
Do Not Archive
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Air Park LL22
Downers Grove, IL 60516
630 985-8503
Message 10
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Subject: | Tire valve extension |
--> AeroElectric-List message posted by: "Mark R Steitle" <mark.steitle@austin.utexas.edu>
Scott,
Thanks for the link. Sounds interesting, but it looks like it would be
difficult to retrofit into an a/c. I like their sending units being
incorporated into the valve stem. Dakota Digital
(www.dakotadigital.com) has a kit (gauge and 4 sensors) for $399. A bit
pricey, but looks like it would work. From what I've read on the
Lancair list, the Lancair ES is very sensitive to tire pressures.
Incorrect tire pressure linked to nose wheel shimmy, and in more than
one case, nose gear collapse. So, this isn't just a neat idea for me,
if it could help prevent nose gear collapse, it could pay for itself
very quickly.
Mark S.
Lancair ES/N208TX
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of N5SL
Subject: RE: AeroElectric-List: Tire valve extension
--> AeroElectric-List message posted by: N5SL <nfivesl@yahoo.com>
Good Morning Mark:
Our new jeep has this feature and I found out when I swapped one of the
wheels with the spare after a flat. Here is an interesting article that
explains how it works:
http://www.wjjeeps.com/tpms.htm
Scott Laughlin
www.cooknwithgas.com
601XL / Corvair
Working on Instrument Panel
Mark R Steitle <mark.steitle@austin.utexas.edu> wrote:
I'm wondering how some vehicles in the the
auto/motorcycle world manage to monitor tire pressures, and could this
be easily adapted to OBAM aircraft?
Mark S.
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
Message 11
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|
Subject: | Tire valve extension |
--> AeroElectric-List message posted by: "Mark R Steitle" <mark.steitle@austin.utexas.edu>
Scott,
On second thought, I don't think this would work with tube type tires.
The Pressure Pro tire pressure monitor uses sensors that screw onto the
valve stem. I guess that is a possibility.
Also, there is one called TireChek that detects tire inflation by
measuring the distance the axel is from the ground (clever). As a tire
looses air, the axel gets closer to the ground. However, it appears
that they are not yet in production. Interesting approach to the
problem though.
Mark S.
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Mark
R Steitle
Subject: RE: AeroElectric-List: Tire valve extension
--> AeroElectric-List message posted by: "Mark R Steitle"
<mark.steitle@austin.utexas.edu>
Scott,
Thanks for the link. Sounds interesting, but it looks like it would be
difficult to retrofit into an a/c. I like their sending units being
incorporated into the valve stem. Dakota Digital
(www.dakotadigital.com) has a kit (gauge and 4 sensors) for $399. A bit
pricey, but looks like it would work. From what I've read on the
Lancair list, the Lancair ES is very sensitive to tire pressures.
Incorrect tire pressure linked to nose wheel shimmy, and in more than
one case, nose gear collapse. So, this isn't just a neat idea for me,
if it could help prevent nose gear collapse, it could pay for itself
very quickly.
Mark S.
Lancair ES/N208TX
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of N5SL
Subject: RE: AeroElectric-List: Tire valve extension
--> AeroElectric-List message posted by: N5SL <nfivesl@yahoo.com>
Good Morning Mark:
Our new jeep has this feature and I found out when I swapped one of the
wheels with the spare after a flat. Here is an interesting article that
explains how it works:
http://www.wjjeeps.com/tpms.htm
Scott Laughlin
www.cooknwithgas.com
601XL / Corvair
Working on Instrument Panel
Mark R Steitle <mark.steitle@austin.utexas.edu> wrote:
I'm wondering how some vehicles in the the
auto/motorcycle world manage to monitor tire pressures, and could this
be easily adapted to OBAM aircraft?
Mark S.
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
Message 12
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|
Subject: | Re: Alternator field breaker |
--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
Is the auxiliary alternator a PM type or conventional (field current
controlled)?
Matt-
> --> AeroElectric-List message posted by: Bernard Despins
> <bdespins@telusplanet.net>
>
> The difficulty I'm having is that in my Velocity XLRG (all electric,
> dual everything except propellers), the auxiliary alternator, regulator,
> and battery are all in the rear. The auxiliary bus does not come to
> the front of the plane. A circuit breaker would not be accessible. Is
> it worth running a wire to the front and back and place a circuit
> breaker on the panel? I do have a circuit breaker for the main
> alternator field.
>
> Bernard Despins
>
> Robert L. Nuckolls, III wrote:
>
>> <>So if using the ov protection built into the LR3C from B & C
>> Specialty, you would suggest using a circuit breaker instead of a
>> fuse?
>>
>> Bernard Despins
>>
>>
>> Correct. This is shown on all drawings provided by B&C and by
>> the 'Connection where the B&C products are illustrated.
>>
>> Bob . . .
>>
>>
>
>
Message 13
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Subject: | Re: Alternator field breaker |
--> AeroElectric-List message posted by: Bernard Despins <bdespins@telusplanet.net>
It is conventional controlled by an LR3C regulator.
Bernard Despins
Matt Prather wrote:
>--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
>
>Is the auxiliary alternator a PM type or conventional (field current
>controlled)?
>
>
>Matt-
>
>
>
>>--> AeroElectric-List message posted by: Bernard Despins
>><bdespins@telusplanet.net>
>>
>>The difficulty I'm having is that in my Velocity XLRG (all electric,
>>dual everything except propellers), the auxiliary alternator, regulator,
>> and battery are all in the rear. The auxiliary bus does not come to
>>the front of the plane. A circuit breaker would not be accessible. Is
>>it worth running a wire to the front and back and place a circuit
>>breaker on the panel? I do have a circuit breaker for the main
>>alternator field.
>>
>>Bernard Despins
>>
>>Robert L. Nuckolls, III wrote:
>>
>>
>>
>>><>So if using the ov protection built into the LR3C from B & C
>>>Specialty, you would suggest using a circuit breaker instead of a
>>>fuse?
>>>
>>>Bernard Despins
>>>
>>>
>>> Correct. This is shown on all drawings provided by B&C and by
>>> the 'Connection where the B&C products are illustrated.
>>>
>>> Bob . . .
>>>
>>>
>>>
>>>
>>
>>
>
>
>
>
Message 14
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Subject: | Re: Alternator field breaker |
--> AeroElectric-List message posted by: Kevin Horton <khorton01@rogers.com>
I believe Bob recommends a CB because it has a faster response time
than a fuse.
If you are prepared to put a fuse in a location where it is not
accessible in flight, why not put the CB in a similar location?
In principle, if the system is properly designed, there should not be
any nusiance CB trips. So if the CB trips and shuts down the
alternator, then you would want to leave it tripped until you get on
the ground.
Kevin Horton
On 15 Sep 2005, at 10:02, Bernard Despins wrote:
> --> AeroElectric-List message posted by: Bernard Despins
> <bdespins@telusplanet.net>
>
> The difficulty I'm having is that in my Velocity XLRG (all electric,
> dual everything except propellers), the auxiliary alternator,
> regulator,
> and battery are all in the rear. The auxiliary bus does not come
> to the
> front of the plane. A circuit breaker would not be accessible. Is it
> worth running a wire to the front and back and place a circuit breaker
> on the panel? I do have a circuit breaker for the main alternator
> field.
>
> Bernard Despins
>
> Robert L. Nuckolls, III wrote:
>
>
>> <>So if using the ov protection built into the LR3C from B & C
>> Specialty,
>> you would suggest using a circuit breaker instead of a fuse?
>>
>> Bernard Despins
>>
>>
>> Correct. This is shown on all drawings provided by B&C and by
>> the 'Connection where the B&C products are illustrated.
>>
>> Bob . . .
>>
>>
>>
Message 15
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Subject: | Re: Alternator field breaker |
--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
CB's are SLOWER than ATC fuses. Probably partly due to having a mechanism
which has to be actuated in order to interrupt.
When at 10x rating (10A rating, 100A fault), fuses may take well less than
100ms (0.1sec) while CB's trip no faster than 800ms or so depending on the
design..
CB's slowness makes them slightly less prone to nuisance trips.
There are slow blow fuses that are slower still, but less common.
A fusible link might be consider a slow blow (slow replacement) fuse.
Regards,
Matt-
> --> AeroElectric-List message posted by: Kevin Horton
> <khorton01@rogers.com>
>
> I believe Bob recommends a CB because it has a faster response time
> than a fuse.
>
> If you are prepared to put a fuse in a location where it is not
> accessible in flight, why not put the CB in a similar location?
>
> In principle, if the system is properly designed, there should not be
> any nusiance CB trips. So if the CB trips and shuts down the
> alternator, then you would want to leave it tripped until you get on
> the ground.
>
> Kevin Horton
>
> On 15 Sep 2005, at 10:02, Bernard Despins wrote:
>
>> --> AeroElectric-List message posted by: Bernard Despins
>> <bdespins@telusplanet.net>
>>
>> The difficulty I'm having is that in my Velocity XLRG (all electric,
>> dual everything except propellers), the auxiliary alternator,
>> regulator,
>> and battery are all in the rear. The auxiliary bus does not come to
>> the
>> front of the plane. A circuit breaker would not be accessible. Is it
>> worth running a wire to the front and back and place a circuit breaker
>> on the panel? I do have a circuit breaker for the main alternator
>> field.
>>
>> Bernard Despins
>>
>> Robert L. Nuckolls, III wrote:
>>
>>
>>> <>So if using the ov protection built into the LR3C from B & C
>>> Specialty,
>>> you would suggest using a circuit breaker instead of a fuse?
>>>
>>> Bernard Despins
>>>
>>>
>>> Correct. This is shown on all drawings provided by B&C and by the
>>> 'Connection where the B&C products are illustrated.
>>>
>>> Bob . . .
>>>
>>>
>>>
>
>
Message 16
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Subject: | Breaker Interrupt Rating |
--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
In the past, I know there has been dispute about breaker interrupt
ratings, and whether the crowbar overly stresses the breakers being used.
While noodling around to confirm my response to Mr. Horton's comment, I
found the following webpage about Klixon 28V breakers.
http://www.ti.com/snc/products/controls/acb-7274.htm
I thought it interesting because the interrupt rating for some of these
devices is listed as "unlimited" (1/2A to 5A rating - will cover the field
breaker). The lowest rating I found was 2000A which is still more than
anyone else's "worst case" analysis of the CB circuit dynamics. This all
supports Mr. Nuckolls testimony on the subject. Using one of these CBs
without ever replacing it would seem to provide plenty of (datasheet
supported) reliability with the loads we've been discussing.
Regards,
Matt-
Message 17
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Subject: | Re: Alternator field breaker |
--> AeroElectric-List message posted by: Bernard Despins <bdespins@telusplanet.net>
My auxiliary bus is essentially the 10 position fuse holder from B and
C. Adding a circuit breaker in the back would add parts and connections
that a simple fuse avoids.
Bernard Despins
Kevin Horton wrote:
>--> AeroElectric-List message posted by: Kevin Horton <khorton01@rogers.com>
>
>I believe Bob recommends a CB because it has a faster response time
>than a fuse.
>
>If you are prepared to put a fuse in a location where it is not
>accessible in flight, why not put the CB in a similar location?
>
>
>Kevin Horton
>
>On 15 Sep 2005, at 10:02, Bernard Despins wrote:
>
>
>
>>--> AeroElectric-List message posted by: Bernard Despins
>><bdespins@telusplanet.net>
>>
>>The difficulty I'm having is that in my Velocity XLRG (all electric,
>>dual everything except propellers), the auxiliary alternator,
>>regulator,
>>and battery are all in the rear. The auxiliary bus does not come
>>to the
>>front of the plane. A circuit breaker would not be accessible. Is it
>>worth running a wire to the front and back and place a circuit breaker
>>on the panel? I do have a circuit breaker for the main alternator
>>field.
>>
>>Bernard Despins
>>
>>Robert L. Nuckolls, III wrote:
>>
>>
>>
>>
>
>
Message 18
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Subject: | degaussing (demagnetizing) my roll bar |
--> AeroElectric-List message posted by: Mickey Coggins <mick-matronics@rv8.ch>
I've read somewhere the instructions on
how to degauss or demagnetize the roll
bar on my RV8, but I can't find them
now. If I recall correctly, it involves
wrapping a power cord around the roll
bar and running a lot of current through
the cord. Hopefully someone can give me
something a bit more detailed. I have a
fairly strong bit of magnetism in my roll
bar, and I want to do this before I install
my windscreen.
Many thanks,
Mickey
--
Mickey Coggins
http://www.rv8.ch/
#82007 finishing
Message 19
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Subject: | Re: avionics wiring hub |
--> AeroElectric-List message posted by: CardinalNSB@aol.com
I too had been thinking about a diy avionics hub, but now I wonder how
useful it will be v. the added parts count/potential for failure.
When I started my project I was bewildered by the avionics wiring, and the
hub seemed like a good idea, I now know there was a lot of power sharing and
amp sharing and light wires, which made it all a mess (since I didn't have
schematics back then).
The way I look at it (small ga plane), the audio panel/intercom will be
fairly permanently wired in, so taking it out will be a big job, so I don't plan
to upgrade it for a long time. The mikes/speakers/intercoms are all tied
to the audio panel. Big deal to remove.
But I do hope to upgrade my "radios" in the near future, so initially I had
thought of the "hub", but..
For the radio/nav/gps (I have a garmin 300/ki202 and a narco mk12d/825),
there are only 4-5 wires from each to the audio panel and now that I have
learned the secret bobby pin tool for my audio panel's incoming Molex connectors
that doesn't seem so bad.
The cdi's will run direct from the radio tray to the cdi, so that comes out
with a simple connector on the cdi. I didn't want to run the cdi wiring into
the hub and then coming out of the hub, lots more parts there.
Power and grounds will run direct, could run through a d sub. So to pop out
a radio rack, pop off the cdi connector, remove power and ground, and use
the bobby pin to take out 5 pins from the back of the audio panel. So when the
non-waas 430's get dumped on the market...
I could run the radio audio/power/ground through a single d sub which would
be easier to disconnect, but more work and more parts, v. pulling a few molex
connectors.
The transponder power/ground will go direct, the connect to the encoder is
already a d sub, I haven't decided what to do about the transponder connect to
the gps.
So when I first got my newbie quote of $800 to install a Icom 200 and $2000
to install a vfr gps, the "hub" seemed attractive. Now, for a basic ga
setup, I don't think so. I am starting this soon, I hope I am right, welcome
any
thoughts?. Skip Simpson
Message 20
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Subject: | Re: degaussing (demagnetizing) my roll bar |
--> AeroElectric-List message posted by: Guy Buchanan <bnn@nethere.com>
If the cord wrap doesn't work, contact Sacramento Sky Ranch. They rent a
demagnetizer with instructions. I did my Kitfox forward frame in just a few
minutes.
At 01:56 PM 9/15/2005, you wrote:
>--> AeroElectric-List message posted by: Mickey Coggins
><mick-matronics@rv8.ch>
>
>I've read somewhere the instructions on
>how to degauss or demagnetize the roll
>bar on my RV8, but I can't find them
>now. If I recall correctly, it involves
>wrapping a power cord around the roll
>bar and running a lot of current through
>the cord. Hopefully someone can give me
>something a bit more detailed. I have a
>fairly strong bit of magnetism in my roll
>bar, and I want to do this before I install
>my windscreen.
>
>Many thanks,
>Mickey
>
>--
>Mickey Coggins
>http://www.rv8.ch/
>#82007 finishing
>
>
Guy Buchanan
K-IV 1200 / 582 / 99% done, thanks to Bob Ducar.
Message 21
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Subject: | Re: degaussing (demagnetizing) my roll bar |
--> AeroElectric-List message posted by: "LarryRobertHelming" <lhelming@sigecom.net>
I am wondering...........how did your roll bar get so heavily magnetized and
how did you determine it was?
I have demagnetized some things like read/write heads on a reel to reel tape
recorder. The process was to attach an electro magnet with a piece of tape
between so it did not actually touch metal to metal with the head and very
slowly move it away while it was energized. Then turn it off. do not
archive cause I do not know the value of this info, if any.
Indiana Larry
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
" Happiness: like a butterfly, when pursued,
is always beyond our grasp, but which,
if one sits quietly, may light upon you."
Nathaniel Hawthorne
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
----- Original Message -----
From: "Mickey Coggins" <mick-matronics@rv8.ch>
Subject: AeroElectric-List: degaussing (demagnetizing) my roll bar
> --> AeroElectric-List message posted by: Mickey Coggins
> <mick-matronics@rv8.ch>
>
> I've read somewhere the instructions on
> how to degauss or demagnetize the roll
> bar on my RV8, but I can't find them
> now. If I recall correctly, it involves
> wrapping a power cord around the roll
> bar and running a lot of current through
> the cord. Hopefully someone can give me
> something a bit more detailed. I have a
> fairly strong bit of magnetism in my roll
> bar, and I want to do this before I install
> my windscreen.
>
> Many thanks,
> Mickey
>
> --
> Mickey Coggins
> http://www.rv8.ch/
> #82007 finishing
>
>
>
Message 22
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|
Subject: | Tire valve extension |
--> AeroElectric-List message posted by: "Robert G. Wright" <armywrights@adelphia.net>
Does anybody think that you'll get some interestingly high readings while
you're at altitude????
Rob
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Mark R
Steitle
Subject: RE: AeroElectric-List: Tire valve extension
--> AeroElectric-List message posted by: "Mark R Steitle"
<mark.steitle@austin.utexas.edu>
Scott,
On second thought, I don't think this would work with tube type tires.
The Pressure Pro tire pressure monitor uses sensors that screw onto the
valve stem. I guess that is a possibility.
Also, there is one called TireChek that detects tire inflation by
measuring the distance the axel is from the ground (clever). As a tire
looses air, the axel gets closer to the ground. However, it appears
that they are not yet in production. Interesting approach to the
problem though.
Mark S.
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Mark
R Steitle
Subject: RE: AeroElectric-List: Tire valve extension
--> AeroElectric-List message posted by: "Mark R Steitle"
<mark.steitle@austin.utexas.edu>
Scott,
Thanks for the link. Sounds interesting, but it looks like it would be
difficult to retrofit into an a/c. I like their sending units being
incorporated into the valve stem. Dakota Digital
(www.dakotadigital.com) has a kit (gauge and 4 sensors) for $399. A bit
pricey, but looks like it would work. From what I've read on the
Lancair list, the Lancair ES is very sensitive to tire pressures.
Incorrect tire pressure linked to nose wheel shimmy, and in more than
one case, nose gear collapse. So, this isn't just a neat idea for me,
if it could help prevent nose gear collapse, it could pay for itself
very quickly.
Mark S.
Lancair ES/N208TX
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of N5SL
Subject: RE: AeroElectric-List: Tire valve extension
--> AeroElectric-List message posted by: N5SL <nfivesl@yahoo.com>
Good Morning Mark:
Our new jeep has this feature and I found out when I swapped one of the
wheels with the spare after a flat. Here is an interesting article that
explains how it works:
http://www.wjjeeps.com/tpms.htm
Scott Laughlin
www.cooknwithgas.com
601XL / Corvair
Working on Instrument Panel
Mark R Steitle <mark.steitle@austin.utexas.edu> wrote:
I'm wondering how some vehicles in the the
auto/motorcycle world manage to monitor tire pressures, and could this
be easily adapted to OBAM aircraft?
Mark S.
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
Message 23
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Subject: | degaussing (demagnetizing) my roll bar |
--> AeroElectric-List message posted by: "Craig Berland" <cberland@systems3.net>
Mickey, take it to a grind shop or mag particle shop. They can de-mag it.
Should take less than 5 minutes.
Craig Berland
>> I've read somewhere the instructions on
> how to degauss or demagnetize the roll
> bar on my RV8, but I can't find them
> now. If I recall correctly, it involves
> wrapping a power cord around the roll
> bar and running a lot of current through
> the cord. Hopefully someone can give me
> something a bit more detailed. I have a
> fairly strong bit of magnetism in my roll
> bar, and I want to do this before I install
> my windscreen.
>
> Many thanks,
> Mickey
>
> --
> Mickey Coggins
> http://www.rv8.ch/
> #82007 finishing
>
>
Message 24
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|
Subject: | RE: Breaker Interrupt Rating |
--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
>In the past, I know there has been dispute about breaker interrupt
>ratings, and whether the crowbar overly stresses the breakers being used.
>While noodling around to confirm my response to Mr. Horton's comment, I
>found the following webpage about Klixon 28V breakers.
>http://www.ti.com/snc/products/controls/acb-7274.htm
>I thought it interesting because the interrupt rating for some of these
>devices is listed as "unlimited" (1/2A to 5A rating - will cover the field
>breaker). The lowest rating I found was 2000A which is still more than
>anyone else's "worst case" analysis of the CB circuit dynamics. This all
>supports Mr. Nuckolls testimony on the subject. Using one of these CBs
>without ever replacing it would seem to provide plenty of (datasheet
>supported) reliability with the loads we've been discussing. Regards, Matt
Clever engineers those Klixon guys. Or maybe not.... Interrupting capacity
per UL1077/IEC934/EN60934 PC1 is defined as the maximum current that a
circuit breaker must interrupt-just one time-without causing a safely
hazard. KaaPowwwww......Operating a circuit breaker outside its published
ratings is a bad idea. Crowbarring cicuit breakers was an historic method
used in the olden days. Good thing that better methods like Linear
Non-crowbar OVP's were invented.
This problem has been fought to the death. It points out how poor an email
list system is at retaining consensus (or illuminating disagreements!)
Recently a number of issues that I thought were buried have arrisen like
Zombies. Oh well, we must be getting close to Halloween.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
Don't worry about people stealing an idea. If it's original, you will have
to ram it down their throats."
-- Howard Aiken
Message 25
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Subject: | Re: Alternator field breaker |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 01:15 PM 9/15/2005 -0600, you wrote:
>--> AeroElectric-List message posted by: Bernard Despins
><bdespins@telusplanet.net>
>
>My auxiliary bus is essentially the 10 position fuse holder from B and
>C. Adding a circuit breaker in the back would add parts and connections
>that a simple fuse avoids.
>
>Bernard Despins
A fuse protected field supply is perfectly acceptable for
safety and as long as you don't get nuisance trips, perfectly
acceptable for operational considerations as well. Given that
nuisance trips are rare and generally easy to fix, your risk
of intractable difficulties is low.
Bob . . .
Message 26
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Subject: | Re: RE: Breaker Interrupt Rating |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 09:25 PM 9/15/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
>
>--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
>
> >In the past, I know there has been dispute about breaker interrupt
> >ratings, and whether the crowbar overly stresses the breakers being used.
> >While noodling around to confirm my response to Mr. Horton's comment, I
> >found the following webpage about Klixon 28V breakers.
>
> >http://www.ti.com/snc/products/controls/acb-7274.htm
>
> >I thought it interesting because the interrupt rating for some of these
> >devices is listed as "unlimited" (1/2A to 5A rating - will cover the field
> >breaker). The lowest rating I found was 2000A which is still more than
> >anyone else's "worst case" analysis of the CB circuit dynamics. This all
> >supports Mr. Nuckolls testimony on the subject. Using one of these CBs
> >without ever replacing it would seem to provide plenty of (datasheet
> >supported) reliability with the loads we've been discussing. Regards, Matt
>
>Clever engineers those Klixon guys. Or maybe not.... Interrupting capacity
>per UL1077/IEC934/EN60934 PC1 is defined as the maximum current that a
>circuit breaker must interrupt-just one time-without causing a safely
>hazard. KaaPowwwww......Operating a circuit breaker outside its published
>ratings is a bad idea. Crowbarring cicuit breakers was an historic method
>used in the olden days.
Don't know about "olden days" . . . and to be sure, high interrupt
currents in the 100+ vac worlds are a whole 'nother ballgame. I have
discussed and provided bench testing, field experience and extensive
investigation of specs and even called my guru at Eaton/Cutler-Hammer
who couldn't understand what all the fuss was about . . .
> Good thing that better methods like Linear Non-crowbar OVP's were invented.
So the crowbar method is "bad" (or should I say "non-better")
. . . again?????
In the aviation/military world, and per the specifications I published,
the breakers we recommend and sell must be tested at max available
interrupt currents in the thousands of amps AND STILL BE FUNCTIONAL
AFTER THE TEST. Of course, due to internal resistance of the breaker
itself plus additional wiring resistances limit the REAL currents
to much less than POTENTIAL currents at 28v. The testing, the field
experience and specifications do not support the allegations.
Crowbar was selected because it met DESIGN GOALS for not increasing
the number places where series resistances would contribute to
voltage regulation instability for systems where bus sense and
field supply are on the same feeder. "Ammeter wiggle" has plagued
thousands of GA aircraft for decades due to this phenomenon. Another
design goal of achieving a solid state solution for replacement of
electro-mechanical relays in a time when robust, hv transistors
were much more expensive. All of the things you you've offered
were considered back then and crowbar won out on all counts.
Years later, some have decided to play the specs game when
in fact, they were blatantly guilty of mis-interpreting and/or
ignoring component specs just as I've been accused of doing. See:
http://aeroelectric.com/articles/spike.pdf
Some numbers tossed around in this thread weren't as wild as the
700A fault currents claimed at the beginning of the latest
discussion started but were no more accurate.
You guys are very long on throwing interpretation of specs around
and short on both hard data and experience. Please, sell all the
series shut down devices you wish . . . shucks, if you want
to peddle ov RELAYS . . . those are fine too. But if the only
way you can sell your products/ideas is to claim my products/
ideas are deficient and use concocted numbers and claims to
support it, it's a sad day for the CONSUMERS of devices who
must make decisions on data no better than that offered by a
commercial for laundry soap.
The challenge still stands. Take any breaker you like and
throw it across a 12v battery as many times as you like and
tell me how many times you have to whack it to trash it.
I've not been able to do it on my bench, maybe your's is
uglier than mine. I've done all the testing I'm going
to do to defend myself against the indefensible . . . the
interminable string of allegations. It's time for you guys
to put up or shut up. Show me the smoke . . .
By the way Eric. I've been trying to identify a connector/tool
combination that works well with that sample of coax I got
from you in Plymouth. It may be great coax but I found it
very user-unfriendly to work with. If you're going to recommend
and/or sell it, I'll suggest you recommend/supply tools and
connectors to mate with it. A step-by-step instruction sheet
to aid the builder in getting it right by the second or third
try would be good too . . .
Bob . . .
Message 27
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Subject: | Re: LED - flashing beacon |
--> AeroElectric-List message posted by: Bob White <bob@bob-white.com>
Hi Richard,
I would suggest using some a solid state switch to turn the power on to
the LED's. Run them in parallel with a series resistor for each LED.
This effectively gives you a constant current source for the LED's.
You might be able to increase the intensity by popping them with higher
than rated currents (smaller resistor), but still keeping the junction
temperature down on the diode because of the duty cycle. Say 20 % on
80 % off and experiment with 1.5X or 2X current levels. (I haven't
tried this.) There's no reason to limit yourself to 3 LED's either.
You can put more LED's in parallel to get more light out.
Bob W.
On Thu, 15 Sep 2005 14:12:54 +0200
"Hoffmann D- Remscheid" <Hoffmann.RS@t-online.de> wrote:
> --> AeroElectric-List message posted by: "Hoffmann D- Remscheid" <Hoffmann.RS@t-online.de>
>
> Hello,
>
> for my homebuilt I want to build a beacon using these white super LED's, three
in series (3 * 3,5V 10.5V). For 12V systems this seems ideal to me.
> The only disadvantage is that you need a constant current source, favourably
in combination with a flashing device. Has anybody done this before? I don't want
to invent the wheel twice (;-)).
>
> Greetings Richard
>
>
>
>
>
>
>
>
--
http://www.bob-white.com
N93BD - Rotary Powered BD-4 (real soon)
Prewired EC2 Cables - http://www.roblinphoto.com/shop/
Message 28
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Subject: | Re: degaussing (demagnetizing) my roll bar |
--> AeroElectric-List message posted by: GMC <gmcnutt@shaw.ca>
Hi Mickey
Is your fuselage located such that the roll bar is close to (underneath)
fluorescent lights. My roll bar & other parts became magnetized sitting
under a four tube fluorescent light fixture in garage. Magnetism bled
off after aircraft was moved to hangar.
George in Langley BC
Mickey Coggins wrote:
>--> AeroElectric-List message posted by: Mickey Coggins <mick-matronics@rv8.ch>
>
>I've read somewhere the instructions on
>how to degauss or demagnetize the roll
>bar -----------snip---------- I have a
>fairly strong bit of magnetism in my roll
>bar, and I want to do this before I install
>my windscreen.
>
>
>
>
Message 29
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Subject: | Re: Alternator field breaker |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 12:25 PM 9/15/2005 -0600, you wrote:
>--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
>
>CB's are SLOWER than ATC fuses. Probably partly due to having a mechanism
>which has to be actuated in order to interrupt.
Every device that functions based on heating effects can be
shown to have what is called an I(squared)*T constant. Look
over the specs for fuses and you'll find this term used in
many discussions of trip characteristics. This characteristic
is relatively constant for any given device and it simply
suggests that if you double the heating current, the trip
time will go down to 1/4th the original value.
When you compare the thermal mass of the heat-sensitive element
in a fuse
http://www.aeroelectric.com/Pictures/ATC-25_1.jpg
with that in a breaker
http://www.aeroelectric.com/Pictures/W31_3.jpg
it's intuitive that the breaker will be much slower to
respond to similar over-current conditions. Inded,
inspection of manufacturer's data on various over-current
protection devices . . .
http://aeroelectric.com/Mfgr_Data
illustrates the relative reaction speeds of a variety
of protective devices for similar overloads. Check out
the ANL series critters at say 5x overload. These "fuses"
are slower than most breakers.
>When at 10x rating (10A rating, 100A fault), fuses may take well less than
>100ms (0.1sec) while CB's trip no faster than 800ms or so depending on the
>design..
>
>CB's slowness makes them slightly less prone to nuisance trips.
>There are slow blow fuses that are slower still, but less common.
>A fusible link might be consider a slow blow (slow replacement) fuse.
There are two classes of "nuisance trips" that have been discussed
lately. Most discussions of NT have focused on the crowbar ov protection
system. This particular nuisance trip is a characteristic of the
OVP device and will be the same irrespective of the style of
over current protection.
The other class of NT arises when the protected system is
subject to prolonged, in-rush currents when loaded with
devices like motors (5-100x but short), very large lamps
(20-70x also short) and pitot heaters (4x and very long).
These kinds of loads drive consideration for selection
of protective devices like thermal breakers, fuses rated
for "slow-blow" characteristics (ANL is one class) or
even fusible links.
Bob . . .
Message 30
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Subject: | Re: RE: Breaker Interrupt Rating |
--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
Hi Eric,
What does the following text mean?
"High Short Circuit Capacity
For its miniature size, the 2TC series offers unusually high current
interrupting capacity. Overloads up to 6,000 amps at 28 VDC or 2,0003,500
amps at 120 VAC, 400 Hz can be safely interrupted without affecting
calibration or operating performance in the standard 2TC series."
http://www.ti.com/snc/products/controls/acb-2tc.htm
Is the fundamental interrupt capability of a 7274 (mentioned before)
different from a 2TC?
You might say that calibration and operating performance applies to the
behavior during only one firey interrupt. However, the calibration curve
only goes to 1000x the rating. On a 1A breaker, 6000A (within spec) is
6000x the rating, and hence off the calibration curve published for the
breaker. Something's missing if interpreted as you suggest. The verbage
above says that the breaker will remain calibrated to spec up to 6000A.
What to do? Somehow getting smoked would seem to characterize the device
as un-calibrated.
Maybe the verbage means what it says. Interrupt a 6000A load and the
calibration is still good. I notice that the bigger breakers are rated to
lower ultimate interrupt capability. Why would a more robust device have
a lower rating? Thermal issues? Bigger breaker stays closed longer
during the ramp-up in current and gets hotter?
I realize that these breakers meet the MIL/UL specs, but just? In the
semiconductor industry that I work in, there are lots of JEDEC specs that
we have to meet in order to play ball. Many of them we meet with LOTS of
margin usually because when a device first came out none of the producers
are sure how to solve some of initial challenges. A little IP later, and
the JEDEC specs aren't even interesting - a new way to cut the knot has
been devised.
Datasheets exist to cover the backsides of the producer, but also to
provide useful information about how to apply a product correctly. If a
breaker isn't reusable after a real-world hard fault, that's one of the
industry's best-kept dirty little secrets. None the less, maybe you're
right, and Rutan is right. Minimum specs end up being performance
ceilings.
Regards,
Matt-
> --> AeroElectric-List message posted by: "Eric M. Jones"
> <emjones@charter.net>
>
> --> AeroElectric-List message posted by: "Matt Prather"
> <mprather@spro.net>
>
>>In the past, I know there has been dispute about breaker interrupt
>> ratings, and whether the crowbar overly stresses the breakers being
>> used. While noodling around to confirm my response to Mr. Horton's
>> comment, I found the following webpage about Klixon 28V breakers.
>
>>http://www.ti.com/snc/products/controls/acb-7274.htm
>
>>I thought it interesting because the interrupt rating for some of these
>> devices is listed as "unlimited" (1/2A to 5A rating - will cover the
>> field breaker). The lowest rating I found was 2000A which is still
>> more than anyone else's "worst case" analysis of the CB circuit
>> dynamics. This all supports Mr. Nuckolls testimony on the subject.
>> Using one of these CBs without ever replacing it would seem to provide
>> plenty of (datasheet supported) reliability with the loads we've been
>> discussing. Regards, Matt
>
>
> Clever engineers those Klixon guys. Or maybe not.... Interrupting
> capacity per UL1077/IEC934/EN60934 PC1 is defined as the maximum
> current that a circuit breaker must interrupt-just one time-without
> causing a safely hazard. KaaPowwwww......Operating a circuit breaker
> outside its published ratings is a bad idea. Crowbarring cicuit
> breakers was an historic method used in the olden days. Good thing that
> better methods like Linear Non-crowbar OVP's were invented.
>
> This problem has been fought to the death. It points out how poor an
> email list system is at retaining consensus (or illuminating
> disagreements!) Recently a number of issues that I thought were buried
> have arrisen like Zombies. Oh well, we must be getting close to
> Halloween.
>
> Regards,
> Eric M. Jones
> www.PerihelionDesign.com
> 113 Brentwood Drive
> Southbridge MA 01550-2705
> (508) 764-2072
>
> Don't worry about people stealing an idea. If it's original, you will
> have to ram it down their throats."
> -- Howard Aiken
>
>
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Subject: | Re: degaussing (demagnetizing) my roll bar |
--> AeroElectric-List message posted by: Mickey Coggins <mick-matronics@rv8.ch>
I'm not really sure how it got magnetized, but it came this
way from Van's. Seems to be a common problem. I checked it
by putting a simple orienteering compass near it. It swings
the needle when about a foot away. My panel mounted compass
will be less than a foot away.
Thanks for the hints.
Best regards,
Mickey
> Is your fuselage located such that the roll bar is close to (underneath)
> fluorescent lights. My roll bar & other parts became magnetized sitting
> under a four tube fluorescent light fixture in garage. Magnetism bled
> off after aircraft was moved to hangar.
>
> George in Langley BC
--
Mickey Coggins
http://www.rv8.ch/
#82007 finishing
do not archive
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Subject: | Re: RE: Breaker Interrupt Rating |
--> AeroElectric-List message posted by: Mickey Coggins <mick-matronics@rv8.ch>
> By the way Eric. I've been trying to identify a connector/tool
> combination that works well with that sample of coax I got
> from you in Plymouth. It may be great coax but I found it
> very user-unfriendly to work with. If you're going to recommend
> and/or sell it, I'll suggest you recommend/supply tools and
> connectors to mate with it. A step-by-step instruction sheet
> to aid the builder in getting it right by the second or third
> try would be good too . . .
I used this wire too. Since it was the first time I've ever
done anything with coax, I just thought working with coax was
hard. Now I feel a bit better! I got the stuff cut, trimmed,
and crimped, but I don't have 100% confidence in the quality
of my work. I was planning on finding out how good it works
on the first flight.
--
Mickey Coggins
http://www.rv8.ch/
#82007 finishing
do not archive
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