Today's Message Index:
----------------------
1. 05:07 AM - Re: This switch OK? (johngoodman)
2. 06:31 AM - Re: Z13/20 (user9253)
3. 06:58 AM - Re: Battery charging (Speedy11@aol.com)
4. 07:08 AM - Re: Questions (Robert L. Nuckolls, III)
5. 07:13 AM - Re: Battery charging (Speedy11@aol.com)
6. 07:13 AM - Loadmeter Shunt 10 amp ()
7. 07:25 AM - Re: Questions ()
8. 08:03 AM - Re: Battery charging (rampil)
9. 08:03 AM - Re: Loadmeter Shunt 10 amp (Tom Barter)
10. 12:15 PM - Re: Z8 (Noah)
11. 03:09 PM - Re: Re: Z13/20 (Gerald Giddens)
12. 03:28 PM - Re: This switch OK? (jerb)
13. 04:46 PM - Re: Re: Z8 (Robert L. Nuckolls, III)
14. 04:55 PM - Re: Re: This switch OK? (Robert L. Nuckolls, III)
15. 06:22 PM - Re: This switch OK? (user9253)
16. 09:47 PM - Re: Re: This switch OK? (B Tomm)
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Subject: | Re: This switch OK? |
> The picture does not specify 250V AC or DC. I will assume that it is AC. I
think it should be safe to use this switch to handle up to 5 amps at 14VDC. A
switch will not immediately self-destruct if operated slightly above its rating.
But its life will be shortened. How much current do you want to control
with this switch and what type of load is it?
> Joe
I want to use it for Coil Power for a GearedDrives LS1 V8 engine in an RV-10. I'm
not sure what the Coil actually draws but the wire is protected by a 15 amp
fuse. The wire from the engine looks like a 14 or 16awg. I'll have to look into
the actual draw, but this switch will probably not work since I need reliability.
Thanks for the reply,
John
--------
#40572 QB. Engine on, wing attach coming soon. Panel delivery soon.
N711JG reserved
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=289034#289034
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David Lamb,
I agree with rck that a relay is better than a switch between the battery and the
E-Bus. RCK mentioned the current handling abilities of the switch. There
is another issue: In case of smoke in the cockpit, there is no way to shut off
power to the E-Bus switch. A relay will give you the ability to open the circuit
on the engine side of the firewall.
The ANL fuse is on the wrong end of the #10 wire. A fuse and a fuselink are
not both needed, although having both does not hurt anything. The protection
device should be as close as practical to the battery contactor. The intent is
to prevent excessive battery current in case of a short circuit. No fuse is
required to protect the alternator output because the alternator current is self
limiting.
Is there over-voltage protection for the main alternator?
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=289041#289041
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Subject: | Re: Battery charging |
Ira,
Good points, all.
If I'm going to ask an opinion of someone on the list, then I certainly
must provide accurate information - or expect no answer.
I'm using Odessey and happy with it so far. I have no intention of
changing at this time. But, I was interested in the answer to the proposed
question. I am always interested in a less expensive, but adequate replacements
for equipment.
Perhaps changing a battery each year is a waste of money. And I've been
called an old FUDdy before, but it is certainly not out of fear,
uncertainty, or doubt.
I change a battery a year because:
1. It is recommended by an expert in the field - Electric Bob
2. My ignorance dictates that I listen to the experts
3. It establishes a reasonable means to avoid failure
4. It is not overly expensive
5. The batteries are used in other equipment and not wasted
6. The oldest battery at any moment in my RV is 2 years.
7. I don't have to bother with capacity checks
I also change my tires before they fail. Anyone who wants the old ones
just let me know.
I change my hoses before they fail. Anybody want the old ones?
I don't like being stranded in remote locations because I tried to stretch
the life of consumables such as batteries.
Just call me an old fuddy.
Ira, thanks for researching the correct info on the battery and providing
your opinion. I appreciate it.
It appears from your comment that you prefer Panasonic batteries. Which
model do you use? Why do you believe that battery is better than an
Odessey? Does it have more AH capacity? Does it have faston tabs or screw on
terminals?
Your suggestion of replacing a battery every two years seems like a
reasonable thing to do - especially if one charges the batteries to capacity
periodically.
Regards,
Stan Sutterfield
Possibly the reason no answer was given was because M&B sells lots
of different batteries, but one of us who have to expend some effort to
figure out what kind of battery it is.
I did so, just because of all the chatter.
It is not a M&B battery, it is a CSB sealed Lead Acid battery
Does not say gel vs immobilized in the little ad.
Its probably ok but I have no experience with the CSB brand,
so you will be a test pilot! After you use it a year let us know
what you found. Half price off an Odessey is not bad unless there is
a reason for the cheapness.
As for swapping out batteries every year: what a waste of money!
Driven by FUD, as the IBMers used to say: Fear, Uncertainty, and Doubt.
If you learn a bit about batteries, then maybe you can still use
premium quality Pana batteries and only swap them every other year!
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At 12:42 AM 3/3/2010, you wrote:
Thanks Bob
I get the freedom that "expecting things to
break" brings. That is very helpful, so thanks.
We all must make a call between no backup and the
backup of the backup to the Nth order.
Many years ago I was a tech working on the Perth Airport ILS system.
All I can remember is that it was the arbiter
that decided which system was functioning
correctly and which was failing, was most often
the part that failed and took the ILS system offline!
What level of redundancy does one go to before
the backups defeat the original purpose and intent.
Yeah. I had an opportunity to craft and install the
cockpit mounted controller for a series of explosively
deployed recovery parachutes in flight test aircraft.
In fact, I'm presently tasked with doing the 4th
such installation for Hawker-Beech.
The design I replaced was horribly complex made so
by some desire to monitor all features of a redundant
and sometimes quad redundant system. Failures were
displayed on an LCD screen. Over a year into the design,
the system could not be made to work because of the
monitoring system kept raising alarms . . . and the
control system ultimately glitched one night and
launched the 'chute in the hangar.
The guys in the Targets group got together and built
one in two weeks.
http://aeroelectric.com/Pictures/Misc/Recovery_Parachute_Controller.jpg
Simple array of relays, solid state sequencer, failure
tolerant, preflight testable, very low comparative
parts count. A little brother to that controller
is on my bench right now awaiting a modern AC mains
powered battery maintainer. A review of the service
history of past installations revealed a lot of replaced
batteries. Seems the crews were pulling the breaker
from ship's DC power when the system was being
"disabled". Then when needed next time, the internal
battery wasn't fully charged.
I'm building a battery maintainer into the controller
with a placard that it be plugged in at least 1 hour
in the 48 hours preceding a flight where the
parachute will be armed.
I suppose where I am still pondering is, given
your systems make sense for aircraft batteries,
alternator/generators and starters (I understand
to be technologically challenged but may be
miss informed), how would they change (if any)
given modern alternators, starters etc? (My
question predicates (foolishly) that all modern
equipment is equal in reliability!!!???)
It's an absolute fact that modern vehicular DC
power components of all stripes are longer lived
and more robust than their ancestors. So yes,
one can comfortably state that reliability of
components has increased . . . in virtually
all technologies and brands.
Perhaps, even if the mean time between failures
has quadrupled in modern equipment the risks still demand your backup systems.
Absolutely.
It's been my observation that the vast majority
of electrical systems unhappiness in OBAM aircraft
(and a substantial number of TC aircraft) DOES
NOT originate in ABILITY OF ANY PART TO DO ITS JOB.
Most problems arise from mis-application of parts and
poor process. Of course, all parts have service
lives and will ultimately cease to function.
From a systems perspective, reliability arguments
that focus on parts are academic and non-productive.
Resolution of such arguments depends heavily on statistical
data derived from laboratory tests that may or may
not accurately mimic service conditions. This is
ESPECIALLY true when service conditions are defined
by the knowledge, resources and skill sets of
the designer/installer.
That's why I started focusing on SYSTEM reliability
through failure mode effects analysis and designs
tolerant of failures. Once this relatively simple skill
was mastered, it mattered little where one
purchases parts. We're now free to concentrate
on the weakest links the OBAM aircraft fabrication
chain . . . knowledge, resources and skill set
of the builder. This is one area where process
trumps science every day.
Again, thanks for the help on the journey and the
decision making that lies at every turn.
My pleasure sir . . .
Bob . . .
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Subject: | Re: Battery charging |
David,
Thanks for your detailed and informative response. Superb info and
analysis.
Stan Sutterfield
Do not archive
This thread piqued my curiosity, so I did a little research. The Panasonic
&
CSB batteries have similar specs apart from the 17/20 AH rating curve.
Their
operating range has a lower limit of -15 C (5 F), and an internal
resistance
of 12-13 mOhms. Internal resistance and temperature range will have a large
impact on cold-weather starting. The CSB is limited to a max of 230 A for 5
sec. The Panasonic specs do not provide this information, but I suspect it
is similar to CSB due to the internal resistance.
At the other end of the battery spectrum is the Osyssey 680. It has a -40 C
(-40 F) lower temperature limit, and 7.5 mOhm internal resistance. They
claim a 680 A discharge rate for 5 sec. and 400 A for 30 seconds. The
longer
time AH capacity is typical for a 16 AH battery. EnerSys (parent company)
also produces the Genesis product line at the same plant as Odyssey in
Warrensburg, Missouri. The Genesis G12V16EP happens to have the same case
design/dimensions, terminals, and electrical specs as the Odyssey 680, but
at a somewhat lower price. They may not be identical, but it's hard to tell
any difference. Aviation is on the Genesis application list, so this might
be a good value. http://tnrbatteries.com/geg11.html Odyssey and Genesis
batteries also have a two year replacement warranty rather than the typical
one year.
Spec sheets (note that Odyssey & Genesis have every detail):
Panasonic:
http://www.panasonic.com/industrial/includes/pdf/Panasonic_VRLA_LC-PD1217P.p
df
CSB: http://www.csb-battery.com/upfiles/dow01242375277.pdf
Odyssey: http://www.odysseybatteries.com/files/techbook.pdf
Genesis:
http://www.enersysreservepower.com/documents/US_GPL_SG_001_0303.pdf
If you're looking at the Panasonic and/or CSB batteries, there are plenty
of
other batteries with similar specs that are even lower cost. Among other
things, I'd pay close attention to the terminal style. Make sure that
vibration won't weaken the terminal over time. Many of these batteries
differ only by the label on top.
If starting current isn't an issue with you, the lower cost batteries may
well be the best value. If you don't want to be stranded with a dead
battery in a cold climate or after a failed hot start, cranking amps will
be
a large part of your decision process. YMMV
David Barrett
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Subject: | Loadmeter Shunt 10 amp |
Can you folks recommend (a link to) a loadmeter shunt for a 10 amp
application (SD-8)? I see B & C has from 20 and up. I tried digi-key but
that place is like sorting through my attic. I prefer the closed type so
I can use it inside my panel.
Thanks,
Glenn
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Once again, thanks Bob, these fundamentals will steer the required decision
s in the right direction.
Steve Izett
Perth WA
On 3/03/10 11:07 PM, "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.c
om> wrote:
s.bob@aeroelectric.com>
At 12:42 AM 3/3/2010, you wrote:
Thanks Bob
I get the freedom that "expecting things to
break" brings. That is very helpful, so thanks.
We all must make a call between no backup and the
backup of the backup to the Nth order.
Many years ago I was a tech working on the Perth Airport ILS system.
All I can remember is that it was the arbiter
that decided which system was functioning
correctly and which was failing, was most often
the part that failed and took the ILS system offline!
What level of redundancy does one go to before
the backups defeat the original purpose and intent.
Yeah. I had an opportunity to craft and install the
cockpit mounted controller for a series of explosively
deployed recovery parachutes in flight test aircraft.
In fact, I'm presently tasked with doing the 4th
such installation for Hawker-Beech.
The design I replaced was horribly complex made so
by some desire to monitor all features of a redundant
and sometimes quad redundant system. Failures were
displayed on an LCD screen. Over a year into the design,
the system could not be made to work because of the
monitoring system kept raising alarms . . . and the
control system ultimately glitched one night and
launched the 'chute in the hangar.
The guys in the Targets group got together and built
one in two weeks.
http://aeroelectric.com/Pictures/Misc/Recovery_Parachute_Controller.jpg
Simple array of relays, solid state sequencer, failure
tolerant, preflight testable, very low comparative
parts count. A little brother to that controller
is on my bench right now awaiting a modern AC mains
powered battery maintainer. A review of the service
history of past installations revealed a lot of replaced
batteries. Seems the crews were pulling the breaker
from ship's DC power when the system was being
"disabled". Then when needed next time, the internal
battery wasn't fully charged.
I'm building a battery maintainer into the controller
with a placard that it be plugged in at least 1 hour
in the 48 hours preceding a flight where the
parachute will be armed.
I suppose where I am still pondering is, given
your systems make sense for aircraft batteries,
alternator/generators and starters (I understand
to be technologically challenged - but may be
miss informed), how would they change (if any)
given modern alternators, starters etc? (My
question predicates (foolishly) that all modern
equipment is equal in reliability!!!???)
It's an absolute fact that modern vehicular DC
power components of all stripes are longer lived
and more robust than their ancestors. So yes,
one can comfortably state that reliability of
components has increased . . . in virtually
all technologies and brands.
Perhaps, even if the mean time between failures
has quadrupled in modern equipment the risks still demand your backup syste
ms.
Absolutely.
It's been my observation that the vast majority
of electrical systems unhappiness in OBAM aircraft
(and a substantial number of TC aircraft) DOES
NOT originate in ABILITY OF ANY PART TO DO ITS JOB.
Most problems arise from mis-application of parts and
poor process. Of course, all parts have service
lives and will ultimately cease to function.
From a systems perspective, reliability arguments
that focus on parts are academic and non-productive.
Resolution of such arguments depends heavily on statistical
data derived from laboratory tests that may or may
not accurately mimic service conditions. This is
ESPECIALLY true when service conditions are defined
by the knowledge, resources and skill sets of
the designer/installer.
That's why I started focusing on SYSTEM reliability
through failure mode effects analysis and designs
tolerant of failures. Once this relatively simple skill
was mastered, it mattered little where one
purchases parts. We're now free to concentrate
on the weakest links the OBAM aircraft fabrication
chain . . . knowledge, resources and skill set
of the builder. This is one area where process
trumps science every day.
Again, thanks for the help on the journey and the
decision making that lies at every turn.
My pleasure sir . . .
Bob . . .
--
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Message 8
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Subject: | Re: Battery charging |
Hi Stan,
Actually I have always used the Odyssey 680 in my Europa. I trust
Pana in terms of general quality, but the specs for the Odyssey are better
for me in the Northeast.
Just changing batteries annually because you don't choose to learn about
batteries (Not talking about anyone individually here) is a shame. Money
is tight all around and frequent changes ignores the real possibility of
infantile failure which is just as likely in the real world as premature failure
if the products are made in the far, far east.
Sometimes experts disagree. This is Bob's group and I respect that.
I appreciate his public service in dealing with the underending series
of questions. There are also other opinions formed on reasonably
solid foundations of knowledge and experience that may differ
however because some experts place different priorities on different
aspects of a project. Look for example on the scrap between Nuckolls
and Richter a few years ago.
I was once an E.E., I spent 8 years in school and grad school, I
try to keep up with the literature and I hand built my plane and panel.
Ergo, I have opinions and they are not always the same as Bob's.
Is is certainly not a dis at Bob when I think there are better places to
spend money than changing out batteries that should be fairly fresh.
(Of course some people know when they have intentionally abused a battery - that
is a different story)
--------
Ira N224XS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=289060#289060
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Subject: | Loadmeter Shunt 10 amp |
Glenn,
I recently purchased a 10 amp shunt for my SD-8 load meter from B&C. It is
the open style, but should be OK behind the panel. That is where mine is
going.
Tom Barter
Kesley, IA
Avid Magnum
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
longg@pjm.com
Sent: Wednesday, March 03, 2010 8:48 AM
Subject: AeroElectric-List: Loadmeter Shunt 10 amp
Can you folks recommend (a link to) a loadmeter shunt for a 10 amp
application (SD-8)? I see B & C has from 20 and up. I tried digi-key but
that place is like sorting through my attic. I prefer the closed type so
I can use it inside my panel.
Thanks,
Glenn
Message 10
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Two questions regarding Z-8.
1. I assume this "new" Z-8 is different from the Z-8 published in 1999 in your
document "All Electric Airplane on a Budget" at:
http://www.matronics.com/aeroelectric/articles/allelect.pdf
If this is the case, why not give the new Z-8 a new name to eliminate confusion?
2. What is the minimum practical battery capacity that would be recommended in
a system as described above, on the bus with the smaller alternator (SD-20 in
my case)? I am not asking from a battery-only loads & endurance standpoint, but
rather from a battery-as-an-alternator-reservoir/voltage-stabilizer standpoint.
I am loathe to install a second battery, contactor, and additional components when
I think my requirements are met without them, but I will certainly have a
long hard look at what is proposed and do some soul searching.
Part of my question stems from the fact that my 16 A-Hr battery is already pretty
much integrated into my platform.
--------
Highest Regards,
Noah Forden
RV-7A
Rhode Island
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=289084#289084
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On Mar 2, 2010, at 7:54 PM, Robert L. Nuckolls, III wrote:
> Might a switch be more efficient than a relay for the E bus load,
assuming a ~10
> amp load? (I'm not refering to the brown out relay which I see is
> necessary).
>
> Certainly more efficient since the switch does not
> draw current to keep it closed. But the relay is
> called for when it is functioning as a mini-contactor
> located adjacent to the battery bus. If you can reach
> a switch located there, then you could consider the
> subsitution.
>
> What do these little Bosch type cube relays draw?
> Thanks, Tim Andres
>
> About 100 mA depending on manufacturer and some
> other details. These are not big energy hogs.
>
> Bob . . .
>
>
>
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Subject: | Re: This switch OK? |
John,
Reading your reply to other folks replies I am concerned of your
using this switch for your intended application.
First off, the switch information you provided in the attachment does
not designate if it is rated for AC or DC current. Note, an AC rated
switch if used in an DC current application, the DC current capacity
will normally be only a fraction of it's AC current rating. Second,
I would point out that the reply by Joe saying that you could
probably run 5 amps of current exceeds the switches current rating,
if it turns out to be an AC application switch, you would be further
outside the switches safe operating limits. Neither would be
acceptable solution.
I strongly recommend you determine your current needs for the circuit
your controlling. Then determine if the switch your considering is
AC or DC rated. If the switch is AC rated, find another switch
appropriate for your application. Do it right the first time, you
might not get the second chance to do it over again.
jerryb
>Attachments:
>
>http://forums.matronics.com//files/picture_1_380.png
>
>
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At 02:10 PM 3/3/2010, you wrote:
>
>Two questions regarding Z-8.
>
>1. I assume this "new" Z-8 is different from the Z-8 published in
>1999 in your document "All Electric Airplane on a Budget" at:
>http://www.matronics.com/aeroelectric/articles/allelect.pdf
>If this is the case, why not give the new Z-8 a new name to
>eliminate confusion?
Many moons ago, the z-figures went from Z-1 to 10 and somewhere
around revision 8 or 9 were replaced with Z-11 and on as they
were redrawn to be more consistent with each other. The suite
of drawings was extended upward from Z-11. It was my plan
at some time to fill the lower numbers back in later. Z-8
was the predecessor to Z-13/8. It only appears in the 1999
article and very old issues of the 'Connection which should
have been updated several times over.
>2. What is the minimum practical battery capacity that would be
>recommended in a system as described above, on the bus with the
>smaller alternator (SD-20 in my case)? I am not asking from a
>battery-only loads & endurance standpoint, but rather from a
>battery-as-an-alternator-reservoir/voltage-stabilizer standpoint.
Technically, any size battery is adequate to the task
of tickling an alternator to life. Batteries are of little
value in noise abatement or voltage stabilization.
Further, the smaller they get, the more they suffer
the 'abuse' of short but heavy charge/discharge
events. Having offered that, I have no idea what would
be considered useful to your task. You'll need to put
some sort of preventative maintenance program on it
or (ugh!) throw a new one in ever so often. It may
be that a tiny (6 a.h. or less) battery wouldn't
support this application for a year . . . I just don't
know. You can just pick one, check it from time to
time and see how it goes. There some small products
by Dekka that feature robust terminals indicative
of an ability to source/sink the transients.
>I am loathe to install a second battery, contactor, and additional
>components when I think my requirements are met without them, but I
>will certainly have a long hard look at what is proposed and do some
>soul searching.
The answer lies not with the soul but with calculated
and considered assembly of ingredients into a recipe
for success that meets your design goals.
The task before you is the same that evolved the
Z-figures over the years. You can look forward
a sifting the details in search of the stable
configuration.
Bob . . .
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Subject: | Re: This switch OK? |
>I want to use it for Coil Power for a GearedDrives LS1 V8 engine in
>an RV-10. I'm not sure what the Coil actually draws but the wire is
>protected by a 15 amp fuse. The wire from the engine looks like a 14
>or 16awg. I'll have to look into the actual draw, but this switch
>will probably not work since I need reliability. Thanks for the reply,
What coil? Ignition? The picture I saw appears to
be a momentary push button. If it has 3 terminals,
then I suspect it's a single-pole, double-throw
device. Further, push-buttons of this style are
slow-make, slow-break (no fast acting over-center
mechanism). VERY poor technology for switching
reactive DC loads.
Bob . . .
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Subject: | Re: This switch OK? |
Looking at the picture of this switch (made in UK), the first thing that came to
mind is that it was going to be used for a starter switch. It turns out that
John intends to use it for a more critical application where a high quality
switch should be used. So I take back what I said about the switch being ok to
use.
As a general rule, a 125VAC rated switch can handle the same current at 14VDC,
even if the manufacturer does not publish the DC rating. Every AC switch has
a DC ampacity. That ampacity might not have been determined by testing and
thus is unknown.
Jerry B. said,
> "the DC current capacity will normally be only a fraction of it's AC current
rating."
That is true if the voltage remains the same: 250V in this case. But, generally speaking, a 125VAC rated switch can carry as much DC current at 14V as it can carry AC current at 125V. An example of this can be seen by reading the data sheet for another switch. http://www.nkkswitches.com/pdf/stoggleslowcap.pdf
Notice that 125VAC rating is identical to the 30VDC rating. At 14VDC, this switch
can handle even more. Also notice that this switch can handle 2 1/2 times
the current at 30VDC than it can at 250VAC. Most good quality snap action AC
switches are suitable for use in homebuilt aircraft as long as the 14VDC current
does not exceed the 125VAC rating of the switch.
Comments are welcome.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=289145#289145
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Subject: | Re: This switch OK? |
Remember...
Switches manufactured in the UK will not work in any north American aircraft
(certified or amateur built) as the current flow requirement is OPPOSITE to
what we consider normal. This is why many switch configurations in the UK
call for switch orientation to be up to be OFF and down to be ON. :)
Just trying to help. We're all in this together. Keep yur sticks on the
ice.
Bevan :)
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of user9253
Sent: Wednesday, March 03, 2010 6:21 PM
Subject: AeroElectric-List: Re: This switch OK?
--> <fran4sew@banyanol.com>
Looking at the picture of this switch (made in UK), the first thing that
came to mind is that it was going to be used for a starter switch. It turns
out that John intends to use it for a more critical application where a high
quality switch should be used. So I take back what I said about the switch
being ok to use.
As a general rule, a 125VAC rated switch can handle the same current at
14VDC, even if the manufacturer does not publish the DC rating. Every AC
switch has a DC ampacity. That ampacity might not have been determined by
testing and thus is unknown.
Jerry B. said,
> "the DC current capacity will normally be only a fraction of it's AC
current rating."
That is true if the voltage remains the same: 250V in this case. But,
generally speaking, a 125VAC rated switch can carry as much DC current at
14V as it can carry AC current at 125V. An example of this can be seen by
reading the data sheet for another switch.
http://www.nkkswitches.com/pdf/stoggleslowcap.pdf
Notice that 125VAC rating is identical to the 30VDC rating. At 14VDC, this
switch can handle even more. Also notice that this switch can handle 2 1/2
times the current at 30VDC than it can at 250VAC. Most good quality snap
action AC switches are suitable for use in homebuilt aircraft as long as the
14VDC current does not exceed the 125VAC rating of the switch.
Comments are welcome.
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=289145#289145
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