Today's Message Index:
----------------------
1. 04:34 AM - Re: is battery filter or dead weight? (Robert L. Nuckolls, III)
2. 04:45 AM - Re: is battery filter or dead weight? (Jan de Jong)
3. 06:36 AM - Re: Questions about the 9005 Low Voltage Module (Robert L. Nuckolls, III)
4. 06:38 AM - Re: is battery filter or dead weight? (Robert L. Nuckolls, III)
5. 06:45 AM - Re: is battery filter or dead weight? (Eric M. Jones)
6. 02:13 PM - Re: Re: is battery filter or dead weight? (Robert L. Nuckolls, III)
7. 02:19 PM - Regulator How Hot (rvg8tor)
8. 04:36 PM - Re: is battery filter or dead weight? (Eric M. Jones)
9. 05:33 PM - Re: Questions about the 9005 Low Voltage Module (Jared Yates)
10. 07:09 PM - Re: Questions about the 9005 Low Voltage Module (Richard E. Tasker)
11. 07:27 PM - Re: Re: is battery filter or dead weight? (Robert L. Nuckolls, III)
12. 10:23 PM - CPC's (Tim Andres)
13. 11:09 PM - Re: CPC's (Don)
14. 11:31 PM - Re: CPC's (Werner Schneider)
15. 11:43 PM - Re: CPC's (Don)
Message 1
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Subject: | Re: is battery filter or dead weight? |
At 11:23 AM 1/2/2011, you wrote:
>
>A question.
>Is a fully charged 12V lead-acid battery held at 14V a voltage stabiliser?
>People seem to think so but I doubt it.
>If you disconnect the battery while the alternator consistently puts
>out over 13V will there be much difference in AC components on the bus?
>Is there an AC on top of DC internal impedance measurement out there
>somewhere that I can't find a reference to?
>I hope somebody knows more.
I think you've already identified the battery
filter myth . . . a myth I once propagated.
There was a sort of "giant capacitor" quality
ascribed to batteries that kind of made sense.
Batteries are indeed a huge energy source/sink
for their size.
If you study battery behavior you'll discover
that they are very non-linear devices. The term
"internal impedance" does not describe a simple
resistive or reactive loss. While a battery
is being heavily discharged (say 12.0v and below)
it can be said to have a very low internal impedance
on the order of tens of milliohms. But while
being charged at 14.0 volts and above, that
impedance value rises. Worse yet, when
the battery is fully charged, it's internal impedance
goes waaayyyy up.
This is why Mil-Std-704 tells us to EXPECT bus voltage
excursions of 3v pk-pk over the range of
1000 to 5000 Hz on a 28v system (1/2 that
on a 14 volt system). The expected/permissible
levels drop off on either side of that band:
Emacs!
Further, 704 is silent as to whether or not there is a battery
present. And it makes sense. A fully charge battery floating
on a normal bus is electrically 'transparent'.
If you experience an alternator runaway, the battery will offer
a significant mitigating load that joins with system loads to
drive the alternator into a current limited mode. This is helpful
in holding down bus voltage while the ov protection system
takes a few tens of milliseconds to shut it down.
Obviously, when the alternator fails, the battery can be
expected to provide the alternate source of energy albeit at
reduced voltage. But as a "filter" small transients that we
call noise, the battery is of no practical value. Dead weight?
Hope not. The thoughtfully maintained battery is the most
reliable source of energy on the airplane.
Bob . . .
Message 2
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Subject: | is battery filter or dead weight? |
Thanks.
I realise that the battery will not allow excursion below 12.5V and will
be an increasing load above 15.5V as long as it lives.
I wonder about its filtering role around 14V when it's neither drawing
or supplying current which is the standard situation.
What might be an equivalent load of capacitor, resistor and inductor
combination?
Jan
The question is not urgent
> Time: 02:37:38 PM PST US
> From: "Noel R.C. Loveys" <noelloveys@yahoo.ca>
> Subject: RE: AeroElectric-List: is battery filter or dead weight?
>
>
> The battery in the circuit will help dissipate voltage spikes. If your
> generator goes into an overvoltage charge situation it won't take long to
> boil the battery. Once that happens the buss will go overvoltage too,
>
> Noel
>
> -----Original Message-----
> From: owner-aeroelectric-list-server@matronics.com
> [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Jan de
> Jong
> Sent: January 2, 2011 1:53 PM
> Subject: AeroElectric-List: is battery filter or dead weight?
>
>
> A question.
> Is a fully charged 12V lead-acid battery held at 14V a voltage stabiliser?
> People seem to think so but I doubt it.
> If you disconnect the battery while the alternator consistently puts out
> over 13V will there be much difference in AC components on the bus?
> Is there an AC on top of DC internal impedance measurement out there
> somewhere that I can't find a reference to?
> I hope somebody knows more.
> Thank you.
> Jan de Jong
>
Message 3
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Subject: | Re: Questions about the 9005 Low Voltage Module |
At 07:57 AM 1/2/2011, you wrote:
>Thanks Bob! Here are the readings that I get. Battery Voltage this
>morning is 12.3.
>
>U107 Pin 1: 0
>U107 Pin 2: 2.38
>U107 Pin 3: .68
>U107 Pin 4: 0
>U107 Pin 7: 11.24
>U107 Pin 8: 11.49
>
>U110 Pin 1: 0
>U110 Pin 2: 10.77
>U110 Pin 3: 0
>U110 Pin 4: 11.49
>U110 Pin 5: 7.66
>U110 Pin 6: 10.78
>U110 Pin 8: 11.49
Okay, all of the voltages you've measured are expected
values with one exception. Pin 3 of U107 voltage is
established by the voltage reference Z103 and SHOULD
be within 30 millivolts or so of 2.50 volts.
http://www.national.com/ds/LM/LM185-2.5.pdf
The fact that you're reading only .68 volts suggests
that Z013 is installed wrong. See data sheet for pinout
orientation . . .
Emacs!
Note that the image is a BOTTOM view
of the device. The pictures for assembly of
the 9005 show the flat side of the device
pointed toward the power transistor location.
If you determine that the device IS
installed wrong you should consider the
best way to replace it. If you have the tools
and experience to removed parts from a plated
thru hole board, you have a high probability
of re-using the original part.
I very seldom pull a part off a board with
any notion of reusing it. The value of the
part is usually pretty small compared to the
value of the whole. I usually clip the leads
on the part to be removed so that they can
be taken out of the holes one at a time thus
minimizing hazard to the board.
Bob . . .
Message 4
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Subject: | is battery filter or dead weight? |
At 06:42 AM 1/3/2011, you wrote:
>
>Thanks.
>I realise that the battery will not allow excursion below 12.5V and
>will be an increasing load above 15.5V as long as it lives.
>I wonder about its filtering role around 14V when it's neither
>drawing or supplying current which is the standard situation.
>What might be an equivalent load of capacitor, resistor and inductor
>combination?
I've never considered researching an "equivalency" . . .
It would depend heavily both on size of the battery
and its physical condition. Given that noise values
for battery-in versus battery-out are indistinguishable
from each other says that noise mitigation benefits,
if any, are insignificantly small.
Bob . . .
Message 5
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Subject: | Re: is battery filter or dead weight? |
It is a little hard to discover if big commercial aircraft have batteries at all.
My guess is that they have some efficient small battery to start the APU, and
not much more. Can an airplane be built without a battery? Sure. There is a
large Russian airplane that can be parked all Winter, then started with the compressed
air stored from a previous flight. If it doesn't start, you have your
prisoners hand-pump in more compressed air.
So having a battery is convenient for starting the airplane, and seems to be a
stabilizing load for the alternator. If the battery is disconnected, plan on some
other stabilization for the alternator, because what comes out of the alternator
is a bumpy DC whose bumps are proportional the the alternator RPM. Modern
electronics are perfectly capable of doing this as well as a big battery, but
modern electronics are going to POL (Point-of-Load), where the "main" power
supply is no longer forced to provide various voltages at various currents and
various stabilities. Instead a single (and perhaps higher voltage) power line
runs around the aircraft, and is then changed at the load to whatever the load
needs by tiny little ICs. This has advantages from several angles, perhaps
the main one being that the system supply and buses don't easily become obsolete.
In my little airplane a-building, I plan an internally-regulated ND alternator
and a power filter using a capacitor, and inductor, Zener and just a few other
parts to give far better filtering than standard Cessnas. Why this is not routine
practice mystifies me.
I might also find a reason to put in a 1.0 F supercapacitor sitting on my shelf.
Such a reason might be that it would reduce the wire size between my battery
and the starter, while (it has been shown) cause the battery life to soar.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones@charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=325420#325420
Message 6
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Subject: | Re: is battery filter or dead weight? |
At 08:41 AM 1/3/2011, you wrote:
>
>It is a little hard to discover if big commercial aircraft have
>batteries at all. My guess is that they have some efficient small
>battery to start the APU, and not much more. Can an airplane be
>built without a battery? Sure. There is a large Russian airplane
>that can be parked all Winter, then started with the compressed air
>stored from a previous flight. If it doesn't start, you have your
>prisoners hand-pump in more compressed air.
The first time I saw the B-57 Canberra,
it was preparing to leave an air show at
McConnell AFB
http://www.b-57canberra.org/b-57sounds.htm
Those were late 40s engines too. It was
amazing to think that a thing which made so
much smoke and noise was doing all that
because it was the best-they-knew-how-to-
do at the time.
Other airplanes have used a variety of
energy sources for engine cranking. I
was once invited to crank up the flywheel
on the engine for getting it started without
success. It's not mean task.
Our J-3 at 1K1 would start on the first
pull of a blade . . . IF you carried out
the right combination of preparation (and
had the prop clocked right on the hub).
Each system left the factory having met certain
design goals. Those goals might be driven by
some combination of customer specs, weight,
costs, space, etc. Some of them caught on in
the consumer markets, others were relegated to
the annals of historical curiosities.
>So having a battery is convenient for starting the airplane, and
>seems to be a stabilizing load for the alternator.
I think we've discussed and demonstrated that
batteries are not "stabilizers" in the common
sense of the word. The battery will assist a
wound field alternator in getting started.
However, the alternator doesn't need the battery
to provide useful output. They will run self-excited
as long as you don't hit the machine with a
hi inrush load that exceeds it's output
current rating thus stalling it.
At Cessna in 1967 or so, we fiddled with ways
to kick start alternators on the 337 should the
battery become unavailable. Ideas included (1) array
of D-cells OR (2) a 3-phase rectifier off the tach
generator. These small energy sources could be
tapped by means of a panel mounted push button
to get the alternators on-line. They were operated
in parallel with one regulator.
Neither idea made it to production as I recall.
We were sandbagging a failure that was very low
on the ladder of probability. That was about
20 years before the idea of a dual feed e-bus
blossomed. THAT would have been a very simple,
low cost alternative to the dragons of the day.
> If the battery is disconnected, plan on some other stabilization
> for the alternator, because what comes out of the alternator is a
> bumpy DC whose bumps are proportional the the alternator RPM.
Have you ever put a 'scope on the bus of
your car, started the engine, and taken trace
pictures of the battery-connected versus
battery disconnected? I was hard pressed
to see any differences. System load had more
effect on noise than the presence of a battery.
I'd like to put a spectrum analyzer on the system
sometime and get some real numbers.
> Modern electronics are perfectly capable of doing this as well as
> a big battery, but modern electronics are going to POL
> (Point-of-Load), where the "main" power supply is no longer forced
> to provide various voltages at various currents and various
> stabilities. Instead a single (and perhaps higher voltage) power
> line runs around the aircraft, and is then changed at the load to
> whatever the load needs by tiny little ICs. This has advantages
> from several angles, perhaps the main one being that the system
> supply and buses don't easily become obsolete.
What supplies and busses have or are becoming
obsolete? Especially those which have or currently
find favor in small airplanes? What are the design
goals driving that "obsolescence"? Do these proposed
technologies portend lower cost, higher reliability,
less weight, increased performance?
I recall visiting a booth at OSH about 15 years ago
where the proprietor was demonstrating an advanced
power distribution and control system. He had a control
box with switches on it for nav, strobe, landing and
taxi lights. One power/data wire came out of the box
and ran to each of those fixtures. Digital data was
transmitted to smart controllers over the power wire
to turn them on/off. What could be simpler? One wire
does it all.
The implications for single points of failure, increased
parts count, increased cost of ownership, etc were
profound. I didn't see him there the next year.
I have perhaps a dozen tools that will set a nail or
stable style fastener. Some electric, some air driven.
But sometimes the best way to drive a nail is with a
hammer. Hammers have been around for a long time.
>In my little airplane a-building, I plan an internally-regulated ND
>alternator and a power filter using a capacitor, and inductor, Zener
>and just a few other parts to give far better filtering than
>standard Cessnas. Why this is not routine practice mystifies me.
In what way? Cars, trucks and all manner of ground
based vehicle have been doing these things for over
100 years to the tunes of hundreds of millions of
examples. Airplanes to hundreds of thousands of
examples. Is it your assertion that the designers
of these vehicles have stubbed their intellectual
toes and failed to exploit some process that
promises improved performance at lower costs of
ownership? As you fly along in any airplane of
any age, are you painfully aware of some deficiency
of performance that cries out for a quieter bus.
>I might also find a reason to put in a 1.0 F supercapacitor sitting
>on my shelf. Such a reason might be that it would reduce the wire
>size between my battery and the starter, while (it has been shown)
>cause the battery life to soar.
Haven't heard of that one. Can you enlighten us
as to the simple-ideas in physics that support
these assertions? 1 Farad hit with a 100A load
discharges at 100 volts per second. This means
that the capacitor will support the battery for
something on the order of 30 milliseconds after
onset of a start cycle. How is this beneficial
to battery life?
Bob . . .
Message 7
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Subject: | Regulator How Hot |
I am planning to use the SD-20 as a back up power source, I have created an Electronic
Equipment Bay out of the lower portion of the RV-8A forward baggage area.
My battery is there, Hot battery bus and ground tabs. I have also installed
the regulator for also SD-20 in this compartment.
A friend asked how hot will that stuff get and I did not have an answer. The SD-20
regulator has a set point below normal bus voltage so it should only come
on if the main alternator goes bad or is turned off, so with the regulator essentially
at idle will it produce much heat, at the same token if operating on
standby alternator, how hot will the regulator get.
Thanks for any help.
--------
Mike "Nemo" Elliott
RV-8A QB (Fuselage)
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=325485#325485
Message 8
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Subject: | Re: is battery filter or dead weight? |
> Haven't heard of that one. Can you enlighten us
> as to the simple-ideas in physics that support
> these assertions? 1 Farad hit with a 100A load
> discharges at 100 volts per second. This means
> that the capacitor will support the battery for
> something on the order of 30 milliseconds after
> onset of a start cycle. How is this beneficial
> to battery life?
Batteries are electrochemical are are thus affected by temperature. SuperCaps,
being electrostatic have no such problem. Thus they are fastened near the starter
and help immensely starting engines in cold climates, or with weak batteries
one might suppose.
Starting an engine is usually separated into three phases: Breakaway, takes the
greatest current as the starter overcomes the static friction of the cold engine.
A SuperCap helps enormously in this breakaway and load shares with current
from the battery, albiet for a short time. Nobody said the initial current was
100A. In fact the SuperCap has the ability to discharge much faster than the
battery--they are very low ESR.
In my earlier life a problematic solenoid attached to a limited supply would just
have a capacitor attached to it (and a diode and a resistor to discharge it
fast and recharge it slowly) so that the capacitor would dump current through
the coil. The plan I mentioned is similar.
But hey, nobody said I suggest this for everyone. But I just might do it.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones@charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=325497#325497
Message 9
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Subject: | Re: Questions about the 9005 Low Voltage Module |
That's great information, thank you for your help! I found the Digikey
invoice and I think I might have ordered the wrong part.
The national part is the Digikey LM285Z-2.5-ND
http://www.national.com/ds/LM/LM185-2.5.pdf
The one that I ordered is made by ON Semiconductor, Digikey
LM285Z-2.5GOS-ND.
http://www.onsemi.com/pub_link/Collateral/LM285-D.PDF
I installed it with the flat side oriented as in the pictures, but didn't
bother to check the spec sheets. National numbers the pins from right to
left, as you pictured below. The ON Numbers them from left to right. The
symbology with regards to the shape of the device seems to be the same
between the two, so I'm not sure if the pin numbers are related to
function or not. Now that I look at the descriptions, the ON is called a
"DIODE REG MICROPWR 2.5V TO-92" while the National is called "IC VOLT REF
MICROPWR 2.5V TO92-3." Does it look like that inadvertent substitution
would be responsible here? In the worst case, I can order one of the
National parts and execute the "snip and swap" as you describe.
On Mon, Jan 3, 2011 at 9:31 AM, Robert L. Nuckolls, III <
nuckolls.bob@aeroelectric.com> wrote:
> At 07:57 AM 1/2/2011, you wrote:
>
> Thanks Bob! Here are the readings that I get. Battery Voltage this
> morning is 12.3.
>
> U107 Pin 1: 0
> U107 Pin 2: 2.38
> U107 Pin 3: .68
> U107 Pin 4: 0
> U107 Pin 7: 11.24
> U107 Pin 8: 11.49
>
> U110 Pin 1: 0
> U110 Pin 2: 10.77
> U110 Pin 3: 0
> U110 Pin 4: 11.49
> U110 Pin 5: 7.66
> U110 Pin 6: 10.78
> U110 Pin 8: 11.49
>
>
> Okay, all of the voltages you've measured are expected
> values with one exception. Pin 3 of U107 voltage is
> established by the voltage reference Z103 and SHOULD
> be within 30 millivolts or so of 2.50 volts.
>
> http://www.national.com/ds/LM/LM185-2.5.pdf
>
> The fact that you're reading only .68 volts suggests
> that Z013 is installed wrong. See data sheet for pinout
> orientation . . .
>
> [image: Emacs!]
>
> Note that the image is a BOTTOM view
> of the device. The pictures for assembly of
> the 9005 show the flat side of the device
> pointed toward the power transistor location.
>
> If you determine that the device IS
> installed wrong you should consider the
> best way to replace it. If you have the tools
> and experience to removed parts from a plated
> thru hole board, you have a high probability
> of re-using the original part.
>
> I very seldom pull a part off a board with
> any notion of reusing it. The value of the
> part is usually pretty small compared to the
> value of the whole. I usually clip the leads
> on the part to be removed so that they can
> be taken out of the holes one at a time thus
> minimizing hazard to the board.
>
>
> Bob . . .
>
Message 10
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Subject: | Re: Questions about the 9005 Low Voltage Module |
Functionally, these are exactly the same parts. For some reason they
chose to number the pins just the opposite of each other. However, if
you installed it so that the flat is in the same orientation they would
operate exactly the same. If you installed it based on the pin
numbering, then that would be a problem.
Dick Tasker
Jared Yates wrote:
> That's great information, thank you for your help! I found the
> Digikey invoice and I think I might have ordered the wrong part.
> The national part is the Digikey LM285Z-2.5-ND
> http://www.national.com/ds/LM/LM185-2.5.pdf
> The one that I ordered is made by ON Semiconductor, Digikey
> LM285Z-2.5GOS-ND.
> http://www.onsemi.com/pub_link/Collateral/LM285-D.PDF
> I installed it with the flat side oriented as in the pictures, but
> didn't bother to check the spec sheets. National numbers the pins
> from right to left, as you pictured below. The ON Numbers them from
> left to right. The symbology with regards to the shape of the device
> seems to be the same between the two, so I'm not sure if the pin
> numbers are related to function or not. Now that I look at the
> descriptions, the ON is called a "DIODE REG MICROPWR 2.5V TO-92" while
> the National is called "IC VOLT REF MICROPWR 2.5V TO92-3." Does it
> look like that inadvertent substitution would be responsible here? In
> the worst case, I can order one of the National parts and execute the
> "snip and swap" as you describe.
>
> On Mon, Jan 3, 2011 at 9:31 AM, Robert L. Nuckolls, III
> <nuckolls.bob@aeroelectric.com <mailto:nuckolls.bob@aeroelectric.com>>
> wrote:
>
> At 07:57 AM 1/2/2011, you wrote:
>> Thanks Bob! Here are the readings that I get. Battery Voltage
>> this morning is 12.3.
>>
>> U107 Pin 1: 0
>> U107 Pin 2: 2.38
>> U107 Pin 3: .68
>> U107 Pin 4: 0
>> U107 Pin 7: 11.24
>> U107 Pin 8: 11.49
>>
>> U110 Pin 1: 0
>> U110 Pin 2: 10.77
>> U110 Pin 3: 0
>> U110 Pin 4: 11.49
>> U110 Pin 5: 7.66
>> U110 Pin 6: 10.78
>> U110 Pin 8: 11.49
>
> Okay, all of the voltages you've measured are expected
> values with one exception. Pin 3 of U107 voltage is
> established by the voltage reference Z103 and SHOULD
> be within 30 millivolts or so of 2.50 volts.
>
> http://www.national.com/ds/LM/LM185-2.5.pdf
>
> The fact that you're reading only .68 volts suggests
> that Z013 is installed wrong. See data sheet for pinout
> orientation . . .
>
> Emacs!
>
> Note that the image is a BOTTOM view
> of the device. The pictures for assembly of
> the 9005 show the flat side of the device
> pointed toward the power transistor location.
>
> If you determine that the device IS
> installed wrong you should consider the
> best way to replace it. If you have the tools
> and experience to removed parts from a plated
> thru hole board, you have a high probability
> of re-using the original part.
>
> I very seldom pull a part off a board with
> any notion of reusing it. The value of the
> part is usually pretty small compared to the
> value of the whole. I usually clip the leads
> on the part to be removed so that they can
> be taken out of the holes one at a time thus
> minimizing hazard to the board.
>
>
> Bob . . .
>
>
> *
>
>
> *
--
Please Note:
No trees were destroyed in the sending of this message. We do concede, however,
that a significant number of electrons may have been temporarily inconvenienced.
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Subject: | Re: is battery filter or dead weight? |
Batteries are electrochemical and thus affected by temperature.
SuperCaps, being electrostatic have no such problem. Thus they are
fastened near the starter and help immensely starting engines in cold
climates, or with weak batteries one might suppose.
I'm having trouble calibrating "immensely" . . .
Starting an engine is usually separated into three phases: Breakaway,
takes the greatest current as the starter overcomes the static
friction of the cold engine. A SuperCap helps enormously in this
breakaway and load shares with current from the battery, albiet for a
short time. Nobody said the initial current was 100A. In fact the
SuperCap has the ability to discharge much faster than the
battery--they are very low ESR.
Absolutely . . . but while capacitors have a greater ability
to deliver CURRENT, their ability to deliver ENERGY is
the fact I'm wrestling with. Total energy stored on a
1F capacitor at 12v is CE(squared)/2 or 72 watt-seconds.
The capacitor can deliver energy into the cranking task
only until its terminal voltage drops to some value equal
to the battery terminal voltage . . . lets assume a cold
weather worst case of 8v whereupon the capacitor still
contains 1*8^2/2 or 32 watt-seconds. Hence, the paralleled
capacitor can offer 40 watt-seconds of stored energy to the
task of getting the engine started for about 50 milliseconds
topes . . . . Assume 100A (small engine) and 9 volts average
for 10 seconds gives 100 * 9 * 10 = 9000 watt-seconds. So
perhaps we see the capacitor contributing less than 1/2 of
1% into the first 1/20 of a second of a cranking scenario.
Does this agree with your calibration of "immensely"?
In my earlier life a problematic solenoid attached to a limited
supply would just have a capacitor attached to it (and a diode and a
resistor to discharge it fast and recharge it slowly) so that the
capacitor would dump current through the coil. The plan I mentioned is similar.
But of course . . . you're getting a boost for the
purposes of aiding an event that takes perhaps 10
milliseconds total and a current level on the order
of tens of amps . . . not ten seconds for hundreds of
amps. These are not similar energy transfer
scenarios.
But hey, nobody said I suggest this for everyone. But I just might do it.
Understand. You brought forth an idea that suggested
"soaring battery life" . . . I'm just making sure
I've not overlooked some new discovery.
Bob . . .
Message 12
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I saw a interesting video tonight from EAA on using circular plastic
connectors.
http://www.eaavideo.org/video.aspx?v=713328494001
Can anyone tell me the part numbers for the connectors he's using? I'd
like to use these for the stick grips and a few other places. I would
like to use the same crimp pins he's using instead of the molex type,
which is about all I could find on a search tonight.
Thanks, Tim Andres
Message 13
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That is a Danials crimper and the pins and sockets are machined . Steinair
has both.
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Tim
Andres
Sent: Monday, January 03, 2011 10:14 PM
Subject: AeroElectric-List: CPC's
I saw a interesting video tonight from EAA on using circular plastic
connectors.
http://www.eaavideo.org/video.aspx?v=713328494001
Can anyone tell me the part numbers for the connectors he's using? I'd
like to use these for the stick grips and a few other places. I would
like to use the same crimp pins he's using instead of the molex type,
which is about all I could find on a search tonight.
Thanks, Tim Andres
Message 14
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This are from Tycoelectronics:
<http://www.tycoelectronics.com/catalog/minf/en/645>
and here 493 products:
<http://www.tycoelectronics.com/catalog/feat/en/c/10574?BML=10576,17560,23645,17584,17760>
bulkier then the db9 I use but if you need more then 9 pins they might
be your choice.
Werner
> Can anyone tell me the part numbers for the connectors he's using? I'd
> like to use these for the stick grips and a few other places. I would
Message 15
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Pins and sockets are on allied electronics catalog page 202 use DM20 p and
s. Series 2 connectors are on page 199
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Don
Sent: Monday, January 03, 2011 11:07 PM
Subject: RE: AeroElectric-List: CPC's
That is a Danials crimper and the pins and sockets are machined . Steinair
has both.
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Tim
Andres
Sent: Monday, January 03, 2011 10:14 PM
Subject: AeroElectric-List: CPC's
I saw a interesting video tonight from EAA on using circular plastic
connectors.
http://www.eaavideo.org/video.aspx?v=713328494001
Can anyone tell me the part numbers for the connectors he's using? I'd
like to use these for the stick grips and a few other places. I would
like to use the same crimp pins he's using instead of the molex type,
which is about all I could find on a search tonight.
Thanks, Tim Andres
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