Today's Message Index:
----------------------
1. 05:48 AM - Re: Follow-up on Carling switch failures. . . (Robert L. Nuckolls, III)
2. 06:02 AM - Re: Follow-up on Carling switch failures. . . (Robert L. Nuckolls, III)
3. 07:11 AM - Re: Using TurboCad (Harley)
4. 07:23 AM - Re: Using TurboCad (LarryMcFarland)
5. 08:07 AM - Re: New RWS EFI/Electcronic Ignition group (Robert McCallum)
6. 08:44 AM - Cessna Flaps motor (bouguy)
7. 09:09 AM - Re: Cessna Flaps motor (David LLoyd)
8. 10:28 AM - Re: Cessna Flaps motor (Robert L. Nuckolls, III)
9. 11:12 AM - Re: Z-14 v Z-14Fadec question (Robert L. Nuckolls, III)
10. 12:16 PM - Re: Using TurboCad (Allen Fulmer)
11. 01:17 PM - Re: Using TurboCad (LarryMcFarland)
12. 01:20 PM - Re: Follow-up on Carling switch failures. . . (B Tomm)
13. 01:23 PM - Re: Follow-up on Carling switch failures. . . (B Tomm)
14. 03:18 PM - Re: Using TurboCad (Allen Fulmer)
15. 03:23 PM - Battery capacity checker (Sam Hoskins)
16. 04:24 PM - Re: Follow-up on Carling switch failures. . . (Robert L. Nuckolls, III)
17. 04:56 PM - Re: Battery capacity checker (Robert L. Nuckolls, III)
18. 05:26 PM - Ground Power (Vern Little)
19. 05:48 PM - Re: Battery capacity checker (Brian R. Wood)
20. 06:30 PM - Re: Using TurboCad (LarryMcFarland)
21. 07:10 PM - Re: Using TurboCad (ROGER & JEAN CURTIS)
22. 09:10 PM - Re: Using TurboCad (Allen Fulmer)
Message 1
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Subject: | Follow-up on Carling switch failures. . . |
At 08:34 PM 1/2/2009, you wrote:
>Vern,
>
>When you say "Carling switches with loose rivets". How loose? Do
>you mean wobbly terminals?
> I've checked all mine and most of the terminals can pivot around
> the rivet until it hits a stop molded into the switch. I wonder if
> this is tight enough. I would expect them to be tighter.
Interesting! The riveted-tabs are obviously not
as rigid about the rivet axis. Some versions do
drop the tab base into a "pocket" molded into the
back of the housing. See:
http://tinyurl.com/96yqmg
I'm away from home for a week so I can't shuffle through
all the switches in my shop. But even with the recesses
shown, the tab isn't really "captured".
> I have a couple Mil-spec switches and I don't think they pivot
> like this but will check again next time I'm at the shop. Maybe
> this pivoting action is what is not compatible with a high
> vibration environment.
I'm aware of no mil-qualified switches that do not feature
terminals molded into the housing. Here's an exemplar
design (Microswitch) . . .
http://tinyurl.com/842eos
>
>I've had two strobe switch failures, one landing light switch
>(actually a wig-wag) failure, and one master switch failure (loose
>rivet but no charred terminals). I have also received brand-new
>Carling switches with loose terminals.
In retrospect, the only thing that resists rotation of
the tabs on the rivets is friction between tab and
housing established coefficient of friction between
plastic/brass and force of the riveted joint. Obviously,
there are limits to the force you can put on the plastic
housing . . .
>
>As an experiment, I replaced several Carling switches with Honeywell
>switches and have been running them, monitoring for failures. I
>proposed about 100 hours of testing before any conclusions could be
>made. This will probably take several more months. I have check
>them in the interim, with no problems.
>
>If the experiment shows failure of the Honeywell switches, then the
>problem may be attributed to my installation.
>If the experiment does not show failure of the Honeywell switches,
>then the problem may be attributed to the Carling switches
>sensitivity to vibration.
>
. . . and I would expect no failures of these devices.
They're exceedingly well designed and tested in environments
our airplanes will never see.
>Bob has concluded that the Carling switches are fine, but should
>have vibration decoupling loops to minimize vibration stresses on
>the terminals. Good advice no matter who's switches are
>installed. Unfortunately, I don't agree that the problem is that my
>(our) installations are incorrect. Rather, I believe that the
>problem is that the Carling switches are unusually sensitive to vibration.
Perhaps 'error' was the wrong term. Lack of understanding
leads to lack of attention to the sensitivities you've
cited . . . and without a doubt, tabs riveted to plastic
housings have a weakness of design where vibration and
temperature cycles are strong.
>
>In my next project, I am planning to use different switches, plus
>decoupling loops. In addition, strobe and landing light loads will
>be isolated with automotive relays which are generally more robust.
It will be interesting to learn of your experience
with this. Certainly addition of the relays will
eliminate all potential for heating effects.
It occurs to me that a little modification of
the Carling (or similar) switches would add some
degree of robustness. There's a product called
JB Weld that offers a process for beefing up
the riveted joints before the switches are installed.
As soon as I get home, I'll do the treatment on
a few switches and publish some photos.
Bob . . .
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Subject: | Follow-up on Carling switch failures. . . |
At 01:25 AM 1/3/2009, you wrote:
>Yes, I am considering contacting the vendor to see if I can return
>them, and change to Milspec switches throughout. I don't really
>want them for a few bucks savings and if the vendor gets enough
>back, perhaps they will offer/recommend a better product.
>
>Bevan
If your worried about them I wouldn't discourage you
from upgrading. Keep in mind that electrical system
failures at the component level in a failure tolerant
design is a low risk event. It's unfortunate that the
price ratio of Carling vs. Microswitch is so large
(about 1:4) but in the grand scheme of things, total
dollars difference in the cost of your project for
going with Microswitch is pretty trivial.
I'm still tantalized by the idea that the Carlings
with fast-on tabs have been around for a very long
time. Adding robustness to the tabs before installation
may offer a low cost means by which our observed
shortcomings may be brought to heel.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
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Subject: | Re: Using TurboCad |
Morning, Bevan...
It's been awhile since I played with TurboCad, I use VisualCad now, but
the basics are pretty much the same in just about any CAD program.
First, you may not be able to work directly with the dwg file, in case
you are. Save it in Turbocad format before doing anything else. Then
close the dwg file, open the Turbocad file and work with that. Although
I have no problem editing Bob's drawings directly in VisualCAD, TurboCad
may be different. Different CAD programs treat dwg drawings differently
and may not allow editing until in the native format.
I just checked one of Bob's Z drawings in my VCADD, and was able to edit
it without any conversions, but it may be different for you in TCADD.
>>Can I not just put a square around a section of the drawing, cut and
paste etc?<<
Yes and no! Remember, unlike the normal graphics we see on computers,
CAD programs are a collection of components like lines, squares, circles
and other geometrics as well as symbols that are complete in
themselves. With a "normal" raster graphic (like a jpg or bmp file)
simply drawing a "square" ("window" in CAD speak) around what you want
to delete, then hitting the delete key removes everything inside the
window.
However, with CADD some of the components may lie OUTSIDE your selection
window (like unseen points used to construct the object you are
seeing...known as construction points. Or the other end of a line or
symbol). When editing, CAD programs consider only COMPLETE objects and
their components that are inside the window as having been selected.
For example, putting a selection window around a straight line but not
including one end of it, will not select that line. Also, curves and
text often have reference points considerably removed from what you see.
Unless these are included in the window, the object you see and want to
work with will not be selected.
In summary, any object whose visible AND invisible parts are inside the
selection window will be selected and can be edited or removed.
I find it easier to just use the selection tool (usually an arrow) to
point to (then click on) an object to see what is included. Whatever
gets highlighted is the entire object that has to be selected to edit.
Right clicking then usually produces a menu of options for the
highlighted (selected) object. Or you can use the delete key, ctrl-c or
ctrl-x if you want to remove it, copy or cut respectively.
To display the normally invisible construction points, which must be
included in the selection, look for the command "Display Construction
Points", or something similar. In Visual CAD it is the two letter
command "DC".
If the item you've selected by clicking on it with the selection pointer
appears to be complex, i.e. made of several lines, circles, curves, etc,
that are all highlighted at once, it has been been made into a symbol.
If you want to remove the entire symbol, you're all set, as it has been
selected in it's entirety. If you want to edit only a portion of it,
then you first have to "de-symbolize" it (now that's a new word!). Look
for a command that will do that. In VCADD, it's "Explode Symbol" (YX).
You will then see the symbol broken down into it's component parts, and
you can edit the individual lines, circles, text, etc.
Hope this helps a bit...remembering Turbocad when I worked with it, I
seem to recall that it had a pretty good help system, so any questions
you have can probably be answered with a bit of search. The learning
curve will eventually get you to the point where you can be comfortable
with the level of drawing that you need. There are many commands and
procedures in VCADD that I don't use, but with the drawing I do, I
probably never will.
Harley Dixon
------------------------------------------------------------------------
B Tomm wrote:
> To the Cad whizzes out there.
>
> I'm taking advantage of the bad weather and trying to
> "professionalize" my wiring diagrams using TurboCad. I'm starting to
> feel really old here cause I'm so frustrated with this TurboCad
> program. I really want to make it work and not get something else.
> I've imported a drawing from Bob's collection in DWG format. All I
> want to do is erase a few lines, re-draw them slightly elsewhere and
> copy a few fuses to add the extra circuits. Erase, copy, cut, paste,
> snap are eluding me even though there are a bazillion tools all
> around. Can I not just put a square around a section of the drawing,
> cut and paste etc?
>
> Jack Daniels is starting to tempt me!
>
> Bevan
>
>
Message 4
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Subject: | Re: Using TurboCad |
Hi Bevan,
The (AutoCAD) Dwg format needs to be saved as a TurboCAD format. That
said, some of the characteristics of line manipulation will not carry over
and you may need to break the drawing down to smaller elements or just
make a new drawing. Starting with the TurboCAD is the better idea and when
you get used to the program, you'll find it twice as fast as AutoCAD and
much more intuitive.
Larry McFarland 601HDS
B Tomm wrote:
> To the Cad whizzes out there.
>
> I'm taking advantage of the bad weather and trying to
> "professionalize" my wiring diagrams using TurboCad. I'm starting to
> feel really old here cause I'm so frustrated with this TurboCad
> program. I really want to make it work and not get something else.
> I've imported a drawing from Bob's collection in DWG format. All I
> want to do is erase a few lines, re-draw them slightly elsewhere and
> copy a few fuses to add the extra circuits. Erase, copy, cut, paste,
> snap are eluding me even though there are a bazillion tools all
> around. Can I not just put a square around a section of the drawing,
> cut and paste etc?
>
> Jack Daniels is starting to tempt me!
>
> Bevan
>
> *
>
>
> *
Message 5
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Subject: | Re: New RWS EFI/Electcronic Ignition group |
Thanks to all who took up my comments and provided the insight and
re-education process. That's the beauty of these lists, continuing
education and new information every day. Yahoo has obviously changed.
Past experience is not always relevant in the fast paced progress of
software and computers. Thanks once again for the enlightenment.
Bob McC
----- Original Message -----
From: Sam Hoskins
To: aeroelectric-list@matronics.com
Sent: Friday, January 02, 2009 7:34 PM
Subject: Re: AeroElectric-List: New RWS EFI/Electcronic Ignition group
I don't know what bad experiences guys have had, but to me Yahoo! is
easy to take. It is easy to upload photos and I would also like to
build up the share links section so guys can share resources, such as
sources for fuel injection parts. Plus, my learning curve on it is very
flat.
Tell you what. If you are interested in the RWS EC2/EC3 controller,
sign up and if you have ANY trouble with it, we'll pull you out of it
ASAP. I have it set up so only aviators can join on my approval and
only the members can post messages. Therefore, there should be NO SPAM.
Yes, Yahoo has small adds, ala Google, but I don't even notice them.
In reality, I anticipate that posts will be fairly far and few
between, since we live in such a small universe.
Sam Hoskins
Murphysboro, IL
www.samhoskins.blogspot.com
On Fri, Jan 2, 2009 at 6:05 PM, Peter Eedy <peter@eedy.id.au> wrote:
<peter@eedy.id.au>
Hi all
I have used PG offline to "manage" yahoo group messages for several
years
now. www.personalgroupware.com
Great program, lets me download the messages from Yahoo and view,
search,
tag etc on my pc.
No affiliation just a satisfied user.
Peter E. Newcastle NSW Australia
Waiex VH-WYX - 20% done
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
Kevin
Horton
Sent: Saturday, 3 January 2009 10:55 AM
To: aeroelectric-list@matronics.com
Subject: Re: AeroElectric-List: New RWS EFI/Electcronic Ignition
group
<khorton01@rogers.com>
Yahoo Groups subscribers can select the option to have messages sent
to them via e-mail. I subscribe to several Yahoo Groups, and am the
group owner for two others, and never have to go to the web site
unless I want to change message delivery options.
Kevin Horton
On 2 Jan 2009, at 14:10, Robert McCallum wrote:
> John;
>
> Maybe I'm not up to speed on the current state of Yahoo, but the
> last time I belonged to a Yahoo list (admittedly several years
ago)
> I had to go to the Yahoo website, log in, wait for 5 minutes of
> garbage ads to unfold, find the list I was interested in, log into
> that then scroll through all of the messages to determine what I'd
> already seen and what was new.
> The Matronics lists just appear as a current message from a
"friend"
> in my regular e-mail and what I've already read is deleted and
gone.
> No fuss, no muss, no hassle, no adverts.
> Sounds from your description that I need to be re-educated on the
> current workings of Yahoo. Thank you for the enlightenment.
>
> Bob McC
>
> Do Not Archive
>
> ----- Original Message -----
> From: John McMahon
> To: aeroelectric-list@matronics.com
> Sent: Friday, January 02, 2009 2:04 PM
> Subject: Re: AeroElectric-List: New RWS EFI/Electcronic Ignition
group
>
> Bob, FWIW I have the LML, the Yahoo ES group and the AeroElectric
> list all sent to my Google gmail account, where they are sent to
> their own folder labels.
>
> They then are all in the same place, in the same format and easy
to
> search in the same way.
>
> Works great for me...
Message 6
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Subject: | Cessna Flaps motor |
Hi ,
i am looking for the current draw of a 24v/28v flap motor
of a Cessna 172 and not able to find it .
thanks for help ,
Boullu guy .
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=222590#222590
Message 7
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Subject: | Re: Cessna Flaps motor |
Probably best to use the flaps circuit breaker rating, amps, in case the
flap mechanism gets stiff or worn and the elect. motor goes to max
current...
D
----- Original Message -----
From: "bouguy" <boullu.guy@libertysurf.fr>
Sent: Saturday, January 03, 2009 8:41 AM
Subject: AeroElectric-List: Cessna Flaps motor
> <boullu.guy@libertysurf.fr>
>
> Hi ,
>
> i am looking for the current draw of a 24v/28v flap motor
> of a Cessna 172 and not able to find it .
>
> thanks for help ,
>
> Boullu guy .
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=222590#222590
>
>
>
Message 8
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Subject: | Re: Cessna Flaps motor |
At 10:41 AM 1/3/2009, you wrote:
>
>Hi ,
>
>i am looking for the current draw of a 24v/28v flap motor
>of a Cessna 172 and not able to find it .
>
>thanks for help ,
>
>Boullu guy .
How do you need to use the information? If for
a load analysis, know that flaps are very low
duty cycle (hence low energy) systems that are
not big players in sizing an electrical system.
If for circuit protection and wiring decisions,
I think you'll find that this critter seldom
draws more than 7 amps (extension during max
allowable IAS for full flaps). You can check the
size of a breaker in any of the 28v s.e. airplanes
and go with that. It's probably a 10 or 15A breaker.
You can wire with 14AWG and go with smaller breaker
and upsize the breaker to and including 20A if
you're getting nuisance trips. Assuming you're
installing this motor/actuator in a OBAM aircraft,
it could be that your flap geometry and air-loads
are decidedly different that for the Cessna
installation.
Wire it with "too-big" wire and leave yourself
room for resizing the breaker/fuse after you've
had some time to acquire real-life experience
with it.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
Message 9
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Subject: | Re: Z-14 v Z-14Fadec question |
>
>Now, I have a general question regarding the Z-14 schemes. For the
>crossover switch, up is to engage the starter with both batteries,
>center is non-crossover, normal mode with batteries working to power
>their bus independently and down is both batteries working together
>on both busses......If I understand correctly. So, in the Z-14
>Fadec scheme, the start button engages the starter, then one
>position on the switch is independent alt to each bus and the other
>switch to have the systems work together? Or, is on position Off and
>the other switch position engaging both alternators to work
>together? If it is the second scenario, does that mean the two
>systems ALWAYS work together? If so, is there any reason not to
>have both systems always working together in the standard Z-14
>scheme. I assume the FADEC label is since it is always engaged
>there is no pilot intervention. Just looking for a better
>understanding. Thanks.
Two ideas drove the crafting the first iteration of of Z-14
many moons ago.
(1) For operators that plan a highly
redundant electrical and instrumentation system
for flight in marginal to adverse conditions,
two independent systems is desirable/
practical by teaming a conventional main alternator
with a vacuum pump pad driven alternator.
(2) Both systems need their own battery. With fully
redundant systems having cross-feed capability, one
may strive for smallest practical batteries with the
notion that battery-only flight is exceedingly
improbable. However, small batteries don't crank
engines well . . . so auto-crossfeed or paralleling
small batteries during engine cranking is a useful
thing to consider.
The two systems are never cross-connected for normal
operations. Each system receives the benefit of
a load analysis. Pairs of redundant electronics
are distributed between the two systems.
Some years later we were offered electro-whizzies
with desirable performance characteristics
under normal operating conditions but not designed
to live in the real-world of vehicular DC power systems.
During starter motor inrush time, system voltage can
sag sufficiently low, sufficiently long . . .
http://tinyurl.com/6tbry6
that some appliances wander off into the weeds or
take an untimely interval to reboot.
These appliances include but are not limited to
electronic ignitions, electronic fuel injection,
EFIS systems, FADECs, etc.
This prompted the addition of two Band-Aids to
the Z-figures. The FADEC version of Z-14 suggested
elimination of the auto-crossfeed feature during
cranking.
Another version of Z-13/8 was crafted to add
a brownout protection battery and auto-disconnect
relay to support e-bus loads during engine-cranking
http://tinyurl.com/7q2usj
The supposition you offered at the end of your post
is not correct. The cross-feed switch in the FADEC
version of Z-14 is never closed except to allow
ONE working alternator to support both sides of the
system (within that alternator's limitations). The
switch is left open all other times. Recalcitrant
systems are operated from the Aux Battery which is
NOT loaded during engine cranking.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
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|
I have had pretty much the same frustrating experience with Turbo CAD! I
bought the version 10 like BobN suggested for $10 or so, but found the
program and internet devoid of any help or tutorials. Finally gave up.
I get regular emails from the IMSI folks trying to get me to upgrade to the
latest version, 15.2, for 50 bucks or so. Anyone care to offer an opinion
on versions?
I need to do something as my hand done drawings (sketches) won't really do
for the finished product.
Allen Fulmer
RV7 Wiring
Alexander City, AL
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of B Tomm
Sent: Friday, January 02, 2009 8:40 PM
To: aeroelectric-list@matronics.com
Subject: AeroElectric-List: Using TurboCad
To the Cad whizzes out there.
I'm taking advantage of the bad weather and trying to "professionalize" my
wiring diagrams using TurboCad. I'm starting to feel really old here cause
I'm so frustrated with this TurboCad program. I really want to make it work
and not get something else. I've imported a drawing from Bob's collection
in DWG format. All I want to do is erase a few lines, re-draw them slightly
elsewhere and copy a few fuses to add the extra circuits. Erase, copy, cut,
paste, snap are eluding me even though there are a bazillion tools all
around. Can I not just put a square around a section of the drawing, cut
and paste etc?
Jack Daniels is starting to tempt me!
Bevan
Message 11
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Subject: | Re: Using TurboCad |
Hi Allen,
TurboCAD is a fine program for one off drawings. Having experienced Pro
E and AutoCAD, I've found TurboCAD is a versatile program if you sit down
and read the reference manual completely. Spend a little time with it
and you can't help but like it. If it's not part of your background,
i.e., engineering or design
you may take a little longer to get on with it, but don't get
discouraged. I used the Aeroelectric guidance and did a
schematic/drawing in TurboCAD
without too many of the formal symbols.
http://www.macsmachine.com/images/electrical/full/primary-wiring.gif
Allen Fulmer wrote:
> I have had pretty much the same frustrating experience with Turbo
> CAD! I bought the version 10 like BobN suggested for $10 or so, but
> found the program and internet devoid of any help or tutorials.
> Finally gave up.
>
> I get regular emails from the IMSI folks trying to get me to upgrade
> to the latest version, 15.2, for 50 bucks or so. Anyone care to offer
> an opinion on versions?
>
> I need to do something as my hand done drawings (sketches) won't
> really do for the finished product.
>
> Allen Fulmer
> RV7 Wiring
> Alexander City, AL
> *
> *
Message 12
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Subject: | Follow-up on Carling switch failures. . . |
RE JB weld.
I had the same thought yesterday. What I don't know is whether the JB weld
will also add some thermal insulation to the joint and cause any excess
heating which will lead to the same result as what we're trying to avoid.
Those big exposed fast on tabs got to be working as radiators, but how much.
Perhaps a dab of JB over the rivet only will have no appreciable affect on
overall cooling.
Anybody know the co-efficient of thermal conductivity of JB weld as it
compares to copper? The fast on tabs on the switches are probably a copper
alloy?
Bevan
_____
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Saturday, January 03, 2009 5:46 AM
Subject: RE: AeroElectric-List: Follow-up on Carling switch failures. . .
At 08:34 PM 1/2/2009, you wrote:
Vern,
When you say "Carling switches with loose rivets". How loose? Do you mean
wobbly terminals?
I've checked all mine and most of the terminals can pivot around the rivet
until it hits a stop molded into the switch. I wonder if this is tight
enough. I would expect them to be tighter.
Interesting! The riveted-tabs are obviously not
as rigid about the rivet axis. Some versions do
drop the tab base into a "pocket" molded into the
back of the housing. See:
http://tinyurl.com/96yqmg
I'm away from home for a week so I can't shuffle through
all the switches in my shop. But even with the recesses
shown, the tab isn't really "captured".
I have a couple Mil-spec switches and I don't think they pivot like this
but will check again next time I'm at the shop. Maybe this pivoting action
is what is not compatible with a high vibration environment.
I'm aware of no mil-qualified switches that do not feature
terminals molded into the housing. Here's an exemplar
design (Microswitch) . . .
http://tinyurl.com/842eos
I've had two strobe switch failures, one landing light switch (actually a
wig-wag) failure, and one master switch failure (loose rivet but no charred
terminals). I have also received brand-new Carling switches with loose
terminals.
In retrospect, the only thing that resists rotation of
the tabs on the rivets is friction between tab and
housing established coefficient of friction between
plastic/brass and force of the riveted joint. Obviously,
there are limits to the force you can put on the plastic
housing . . .
As an experiment, I replaced several Carling switches with Honeywell
switches and have been running them, monitoring for failures. I proposed
about 100 hours of testing before any conclusions could be made. This will
probably take several more months. I have check them in the interim, with
no problems.
If the experiment shows failure of the Honeywell switches, then the problem
may be attributed to my installation.
If the experiment does not show failure of the Honeywell switches, then the
problem may be attributed to the Carling switches sensitivity to vibration.
. . . and I would expect no failures of these devices.
They're exceedingly well designed and tested in environments
our airplanes will never see.
Bob has concluded that the Carling switches are fine, but should have
vibration decoupling loops to minimize vibration stresses on the terminals.
Good advice no matter who's switches are installed. Unfortunately, I don't
agree that the problem is that my (our) installations are incorrect.
Rather, I believe that the problem is that the Carling switches are
unusually sensitive to vibration.
Perhaps 'error' was the wrong term. Lack of understanding
leads to lack of attention to the sensitivities you've
cited . . . and without a doubt, tabs riveted to plastic
housings have a weakness of design where vibration and
temperature cycles are strong.
In my next project, I am planning to use different switches, plus decoupling
loops. In addition, strobe and landing light loads will be isolated with
automotive relays which are generally more robust.
It will be interesting to learn of your experience
with this. Certainly addition of the relays will
eliminate all potential for heating effects.
It occurs to me that a little modification of
the Carling (or similar) switches would add some
degree of robustness. There's a product called
JB Weld that offers a process for beefing up
the riveted joints before the switches are installed.
As soon as I get home, I'll do the treatment on
a few switches and publish some photos.
Bob . . .
Message 13
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Subject: | Follow-up on Carling switch failures. . . |
I agree and adding JB would be the faster and easier way to go. Trouble is,
it's all just theory for now, and the airplane is becoming a reality fast.
Bevan
_____
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Saturday, January 03, 2009 6:01 AM
Subject: RE: AeroElectric-List: Follow-up on Carling switch failures. . .
At 01:25 AM 1/3/2009, you wrote:
Yes, I am considering contacting the vendor to see if I can return them, and
change to Milspec switches throughout. I don't really want them for a few
bucks savings and if the vendor gets enough back, perhaps they will
offer/recommend a better product.
Bevan
If your worried about them I wouldn't discourage you
from upgrading. Keep in mind that electrical system
failures at the component level in a failure tolerant
design is a low risk event. It's unfortunate that the
price ratio of Carling vs. Microswitch is so large
(about 1:4) but in the grand scheme of things, total
dollars difference in the cost of your project for
going with Microswitch is pretty trivial.
I'm still tantalized by the idea that the Carlings
with fast-on tabs have been around for a very long
time. Adding robustness to the tabs before installation
may offer a low cost means by which our observed
shortcomings may be brought to heel.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
Message 14
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Thanks for the encouragement, Larry.
Any comment on version 10 vs. latest (15.2 at this time)?
Thanks,
Allen
>>>-----Original Message-----
>>>From: owner-aeroelectric-list-server@matronics.com
>>>[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of
>>>LarryMcFarland
>>>Sent: Saturday, January 03, 2009 3:06 PM
>>>To: aeroelectric-list@matronics.com
>>>Subject: Re: AeroElectric-List: Using TurboCad
>>>
>>>
>>><larry@macsmachine.com>
>>>
>>>Hi Allen,
>>>TurboCAD is a fine program for one off drawings. Having
>>>experienced Pro
>>>E and AutoCAD, I've found TurboCAD is a versatile program if
>>>you sit down
>>>and read the reference manual completely. Spend a little
>>>time with it
>>>and you can't help but like it. If it's not part of your background,
>>>i.e., engineering or design
>>>you may take a little longer to get on with it, but don't get
>>>discouraged. I used the Aeroelectric guidance and did a
>>>schematic/drawing in TurboCAD
>>>without too many of the formal symbols.
>>>http://www.macsmachine.com/images/electrical/full/primary-wiring.gif
>>>
>>>
>>>Allen Fulmer wrote:
>>>> I have had pretty much the same frustrating experience with Turbo
>>>> CAD! I bought the version 10 like BobN suggested for $10
>>>or so, but
>>>> found the program and internet devoid of any help or tutorials.
>>>> Finally gave up.
>>>>
>>>> I get regular emails from the IMSI folks trying to get me
>>>to upgrade
>>>> to the latest version, 15.2, for 50 bucks or so. Anyone
>>>care to offer
>>>> an opinion on versions?
>>>>
>>>> I need to do something as my hand done drawings (sketches) won't
>>>> really do for the finished product.
>>>>
>>>> Allen Fulmer
>>>> RV7 Wiring
>>>> Alexander City, AL
>>>> *
>>>> *
>>>
>>>
>>>
>>>
>>>
>>>
>>>
Message 15
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Subject: | Battery capacity checker |
I stumbled across this home brewed battery capacity tester, using a power
inverter. Neat idea.
http://www.instructables.com/id/AmpHourTest/
Sam Hoskins
Murphysbro, IL
Message 16
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Subject: | Follow-up on Carling switch failures. . . |
At 03:12 PM 1/3/2009, you wrote:
>RE JB weld.
>
>I had the same thought yesterday. What I don't know is whether the
>JB weld will also add some thermal insulation to the joint and cause
>any excess heating which will lead to the same result as what we're
>trying to avoid. Those big exposed fast on tabs got to be working
>as radiators, but how much. Perhaps a dab of JB over the rivet only
>will have no appreciable affect on overall cooling.
Vern mentioned something last night that triggered another
thought of my own today. Certainly vibration and bending
moments put these joints at risk for loosening . . . but
lack of gas-tightness increases resistance due to corrosion
too. If you've got some switches to play with, see if the
rivet is of an material that will readily alloy with 63/37 solder.
We know that the brass tab will. If you can get a solder-cap
over the rivet-to-tab interface AND THEN mechanically secure
the tab with JB Weld, we may well have deduced the simplest 'fix'.
>
>Anybody know the co-efficient of thermal conductivity of JB weld as
>it compares to copper? The fast on tabs on the switches are
>probably a copper alloy?
Heat rejection in a properly functioning switch is not
an issue. Further, more heat is carried away on the fast-on
terminal and wire than is radiated from the small portion
of tab that would be covered by JB Weld. The kind of heat
that accelerates destruction of the switch happens AFTER
joint integrity is lost. Solder+Potting goes to protection
of that integrity.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
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Subject: | Re: Battery capacity checker |
At 05:22 PM 1/3/2009, you wrote:
>I stumbled across this home brewed battery capacity tester, using a
>power inverter. Neat idea.
>
><http://www.instructables.com/id/AmpHourTest/>http://www.instructables.com/id/AmpHourTest/
>
>Sam Hoskins
>Murphysbro, IL
Pretty slick. This is an extension of an idea I published
in the battery chapter of the 'Connection way back when.
A reprint of that idea was excerpted about 10 years ago
and published at:
http://www.aeroelectric.com/articles/battest.pdf
The idea discovered by Sam is interesting in that it
takes advantage of the end-of-discharge detection
feature built into many inverters (usually 100W or
greater). It also has the advantage of choosing
combinations of 120 volt bulbs for sizing load
as opposed to 12 volt devices.
As one reader suggested in the comments under the
posting, one should probably put a good ammeter
in series with the DC power leads to the inverter
and then adjusting the number and size of lamps to
achieve the desired load on the battery.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
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Bob, there's been some discussion on ground power setup over on the VAF
list, and there's an issue that has come up that needs your sage advise.
My design is based on a modified version of the one you have published
(I use the milspec plug and add an over-ride so that I can force power
out of the connector as well). Another builder has a different design
that feeds the electrical system after the master contactor (not
directly to the battery): See
http://nerv10.com/wcurtis/90Electric...eBookPage2.pdf.
I contend that if he has a dead battery, he cannot charge it with ground
power, or even with a running engine. In my opinion, this defeats one
of the purposes of ground power, which is jump-starting an aircraft with
a dead battery. Since you can't fly without electrical power
(usually). He claims that this is the way Cessna does it, and maybe
they think that if you have a dead battery, you should charge it with a
proper charger rather than jumpstarting and using your (overstressed)
alternator to do the job for you.
What are your thoughts on this?
The list is here:
http://www.vansairforce.com/community/showthread.php?p=286211#post28621
1
Thanks,
Vern Little
Message 19
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Subject: | Re: Battery capacity checker |
Shouldn't you have to take into account the effciency of the inverter
also, to get usable results?
Brian in Brazil
Em Sat, 03 Jan 2009 22:54:00 -0200, Robert L. Nuckolls, III
<nuckolls.bob@aeroelectric.com> escreveu:
> At 05:22 PM 1/3/2009, you wrote:
>> I stumbled across this home brewed battery capacity tester, using a
>> power inverter. Neat idea.
>>
Message 20
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Subject: | Re: Using TurboCad |
Allen,
I started with version 8 a long time ago, but kept upgrading and using
TurboCAD to put models into a TrueSpace
program. Pro E was dropped at work and I got involved in modeling
military equipment that the USMC needed. Several
upgrades included V10 and it's still a good program. I now use version
15 (mechanical) and it supports pretty much anything you
want to do. A small price for a program that does 3-D modeling so well.
It even has a good rendering capability that
provides material surfacing, accurate reflections and shadowing. that
can be used within (Light Wave) an animation
program that I use. If you intend to advance your work or employment
with engineering drawings, TurboCAD
is a fine program to know. If you only need it for the current wiring
diagrams, and your aircraft project, then Version 10
is likely all you'll ever really need.
Larry McFarland 601HDS at www.macsmachine.com
do not archive
Allen Fulmer wrote:
>
> Thanks for the encouragement, Larry.
>
> Any comment on version 10 vs. latest (15.2 at this time)?
>
> Thanks,
>
> Allen
>
>
Message 21
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I purchased the tutorial from IMSI. I found it to be quite good for a
relative beginner. There are a lot of subtleties that are hard to
ferret
out of the manual alone, and the tutorial leads you through many of
these
and gives you a very good starting point.
Good luck,
Roger
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Allen
Fulmer
Sent: Saturday, January 03, 2009 3:13 PM
Subject: RE: AeroElectric-List: Using TurboCad
I have had pretty much the same frustrating experience with Turbo CAD!
I
bought the version 10 like BobN suggested for $10 or so, but found the
program and internet devoid of any help or tutorials. Finally gave up.
I get regular emails from the IMSI folks trying to get me to upgrade to
the
latest version, 15.2, for 50 bucks or so. Anyone care to offer an
opinion
on versions?
I need to do something as my hand done drawings (sketches) won't really
do
for the finished product.
Allen Fulmer
RV7 Wiring
Alexander City, AL
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of B Tomm
Sent: Friday, January 02, 2009 8:40 PM
Subject: AeroElectric-List: Using TurboCad
To the Cad whizzes out there.
I'm taking advantage of the bad weather and trying to "professionalize"
my
wiring diagrams using TurboCad. I'm starting to feel really old here
cause
I'm so frustrated with this TurboCad program. I really want to make it
work
and not get something else. I've imported a drawing from Bob's
collection
in DWG format. All I want to do is erase a few lines, re-draw them
slightly
elsewhere and copy a few fuses to add the extra circuits. Erase, copy,
cut,
paste, snap are eluding me even though there are a bazillion tools all
around. Can I not just put a square around a section of the drawing,
cut
and paste etc?
Jack Daniels is starting to tempt me!
Bevan
Message 22
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Thanks Larry,
Guess I'll give it a try again. And maybe contact IMSI re: upgrade and/or
tutorials.
And I've bookmarked your web site to see what you have done.
Allen
DO NOT ARCHIVE
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