Today's Message Index:
----------------------
1. 06:04 AM - Dark and stormy night during CAVU (Ernest Christley)
2. 06:38 AM - Re: Dark and stormy night during CAVU (Bob Verwey)
3. 07:00 AM - Re: Dark and stormy night during CAVU (Charlie England)
4. 07:11 AM - Re: Dark and stormy night during CAVU (Alec Myers)
5. 08:00 AM - Re: Dark and stormy night during CAVU (Ernest Christley)
6. 08:38 AM - Switch Question (farmrjohn)
7. 09:04 AM - Re: Dark and stormy night during CAVU (Robert L. Nuckolls, III)
8. 09:46 AM - Slickstart Current Draw update ()
9. 12:06 PM - Z101B Questions (Patrick Nelson)
10. 01:22 PM - Re: Dark and stormy night during CAVU (Robert L. Nuckolls, III)
11. 01:35 PM - Re: Switch Question (user9253)
12. 01:46 PM - Re: Switch Question (Robert L. Nuckolls, III)
13. 02:42 PM - Re: Z101B Questions (user9253)
14. 04:07 PM - Re: Switch Question (Robert L. Nuckolls, III)
15. 04:11 PM - Re: Slickstart Current Draw update (Robert L. Nuckolls, III)
16. 04:30 PM - Re: Z101B Questions (Robert L. Nuckolls, III)
17. 07:29 PM - Re: Dark and stormy night during CAVU (dj_theis)
18. 07:53 PM - Re: Switch Question (farmrjohn)
19. 09:23 PM - Re: heat probe (manishajay)
20. 09:45 PM - Re: Slickstart Current Draw update ()
Message 1
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| Subject: | Dark and stormy night during CAVU |
My plane has been stranded all summer at KTTA, which is a 25 minute flight
from my home airport, KJNX.=C2- That's a good hour drive.=C2- I broke a
pushrod while on approach there back in the early summer.=C2- Finally go
t the engine back on and flew her home this past Saturday.=C2- I wasn't a
t all comfortable with this flight, even though I had spent hours flying to
uch and goes around KTTA, so my buddy, Dwight, agreed to fly chase. =C2-
Halfway home, the RPM indicator started dropping.=C2- I reported the prob
lem to Dwight, and he guided me to Triple-W, but on the way down I was noti
cing that the speed wasn't dropping.=C2- In fact, I checked and was able
to climb AND speed up!!=C2- I also wasn't hearing the RPM drop off like t
he tachometer was indicating it should.
I soon identified the suspect to be where I was picking up the RPM signal f
rom.=C2- I was using the signal produced by the permanent magnet generato
r, and I had replaced my old generator with a new, stronger one.=C2- The
permanent magnets produce an AC signal that is exactly 3 pulses per revolut
ion.=C2- Until the regulator hits its set point, that is.=C2- Once the
battery is fully charged, the regulator switches the signal off, it goes hi
gh, and stays there.=C2- The engine monitor no longer sees a pulse, just
a high value and interprets that as a lower RPM.=C2- I checked the theory
by turning on every electrical load I had, and sure enough the RPM started
rising without touching the throttle.=C2- The RPM didn't go all the way
back up,
I have to find another method of picking up the rpm.=C2- I already have a
reluctor.=C2- Just have to install it.=C2- But, a word to the wise. .
. don't use the generator as a tachometer source.=C2- This is experimenta
l aviation, and I consider this experiment to be a success.=C2- I learned
something, and no metal was bent in the process.
Message 2
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| Subject: | Re: Dark and stormy night during CAVU |
Interesting stuff!
Best Regards,
Bob Verwey
082 331 2727
On Tue, 24 Nov 2020 at 16:13, Ernest Christley <echristley@att.net> wrote:
> My plane has been stranded all summer at KTTA, which is a 25 minute flight
> from my home airport, KJNX. That's a good hour drive. I broke a pushrod
> while on approach there back in the early summer. Finally got the engine
> back on and flew her home this past Saturday. I wasn't at all comfortable
> with this flight, even though I had spent hours flying touch and goes
> around KTTA, so my buddy, Dwight, agreed to fly chase.
>
> Halfway home, the RPM indicator started dropping. I reported the problem
> to Dwight, and he guided me to Triple-W, but on the way down I was
> noticing that the speed wasn't dropping. In fact, I checked and was able
> to climb AND speed up!! I also wasn't hearing the RPM drop off like the
> tachometer was indicating it should.
>
> I soon identified the suspect to be where I was picking up the RPM signal
> from. I was using the signal produced by the permanent magnet generator,
> and I had replaced my old generator with a new, stronger one. The
> permanent magnets produce an AC signal that is exactly 3 pulses per
> revolution. Until the regulator hits its set point, that is. Once the
> battery is fully charged, the regulator switches the signal off, it goes
> high, and stays there. The engine monitor no longer sees a pulse, just a
> high value and interprets that as a lower RPM. I checked the theory by
> turning on every electrical load I had, and sure enough the RPM started
> rising without touching the throttle. The RPM didn't go all the way back
> up,
>
> I have to find another method of picking up the rpm. I already have a
> reluctor. Just have to install it. But, a word to the wise. . . don't use
> the generator as a tachometer source. This is experimental aviation, and I
> consider this experiment to be a success. I learned something, and no
> metal was bent in the process.
>
>
Message 3
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| Subject: | Re: Dark and stormy night during CAVU |
On Tue, Nov 24, 2020 at 8:13 AM Ernest Christley <echristley@att.net> wrote:
> My plane has been stranded all summer at KTTA, which is a 25 minute flight
> from my home airport, KJNX. That's a good hour drive. I broke a pushrod
> while on approach there back in the early summer. Finally got the engine
> back on and flew her home this past Saturday. I wasn't at all comfortable
> with this flight, even though I had spent hours flying touch and goes
> around KTTA, so my buddy, Dwight, agreed to fly chase.
>
> Halfway home, the RPM indicator started dropping. I reported the problem
> to Dwight, and he guided me to Triple-W, but on the way down I was
> noticing that the speed wasn't dropping. In fact, I checked and was able
> to climb AND speed up!! I also wasn't hearing the RPM drop off like the
> tachometer was indicating it should.
>
> I soon identified the suspect to be where I was picking up the RPM signal
> from. I was using the signal produced by the permanent magnet generator,
> and I had replaced my old generator with a new, stronger one. The
> permanent magnets produce an AC signal that is exactly 3 pulses per
> revolution. Until the regulator hits its set point, that is. Once the
> battery is fully charged, the regulator switches the signal off, it goes
> high, and stays there. The engine monitor no longer sees a pulse, just a
> high value and interprets that as a lower RPM. I checked the theory by
> turning on every electrical load I had, and sure enough the RPM started
> rising without touching the throttle. The RPM didn't go all the way back
> up,
>
> I have to find another method of picking up the rpm. I already have a
> reluctor. Just have to install it. But, a word to the wise. . . don't use
> the generator as a tachometer source. This is experimental aviation, and I
> consider this experiment to be a success. I learned something, and no
> metal was bent in the process.
>
>
Yeah, there are times when I'm too smart for my own good, as
well....Congrats on remembering to 'fly the plane'; you're obviously a
better pilot than the highly trained airline crew that flew an airliner
into the ground while playing with a circuit breaker. And congrats on a
safe outcome, as well.
Charlie
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Message 4
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| Subject: | Re: Dark and stormy night during CAVU |
>> don't use the generator as a tachometer source.
I have a type certified aircraft that does it uses a commercial (BOSCH) 28v truck
alternator, and an automotive tach. All flight instruments are (should be)
single point redundant. You just have to know that if the alternator belt fails
or the alternator has to be taken offline for some reason, you have to manage
without the tach. Not a big deal.
Message 5
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| Subject: | Re: Dark and stormy night during CAVU |
Ahh!=C2- You have an alternator.=C2- An alternator controls the output
power by decreasing the power going to the electromagnet.=C2- If the sys
tem needs a tenth of the name plate rating of the alternator, the circuit d
rops the input to one tenth.=C2- The output pulses from the stator contin
ue...albeit, at one tenth the power.
With a generator, there is no way to manage the strength of the magnets.=C2
- So=C2- to control output, the regulator just switches off the circuit
coming from the stator.=C2- At least with this regulator.=C2- If I wer
e using a shunt regulator, it would let the stator keep on pushing electron
s, and then dump the unneeded ones to ground through a resistor.=C2- The
pulses would continue in that case.
I would be happy to live with a bum RPM signal in the case where the altern
ator broke.=C2- But, this is a bum RPM signal when the thing is working a
s (poorly) designed.=C2- :-(
On Tuesday, November 24, 2020, 10:12:11 AM EST, Alec Myers <alec@alecmye
rs.com> wrote:
>> don't use the generator as a tachometer source.
I have a type certified aircraft that does it uses a commercial (B
OSCH) 28v truck alternator, and an automotive tach. All flight instruments
are (should be) single point redundant. You just have to know that if the a
lternator belt fails or the alternator has to be taken offline for some rea
son, you have to manage without the tach. Not a big deal.
-
S -
WIKI -
-
=C2- =C2- =C2- =C2- =C2- -Matt Dralle, List Admin.
Message 6
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My master switch is specified as an AN 3023-2. I have been unable to find any
documentation on just what that is, other than some type of DPST switch. Is there
a source for decoding the AN switch specifications?
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=499495#499495
Message 7
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| Subject: | Re: Dark and stormy night during CAVU |
At 09:06 AM 11/24/2020, you wrote:
>
>
> >> don't use the generator as a tachometer source.
>
>I have a type certified aircraft that does=85 it
>uses a commercial (BOSCH) 28v truck alternator,
>and an automotive tach. All flight instruments
>are (should be) single point redundant. You just
>have to know that if the alternator belt fails
>or the alternator has to be taken offline for
>some reason, you have to manage without the tach. Not a big deal.
Exactly. It's useful to 'become one' with your airplane
as opposed to being an 'operator'. I recall a fairly
'experienced' pilot showing up a K1K1 wanting to exploit
our rental fleet. I invited him to join me in a 150 and
to show me his stuff.
We went around the patch a couple of times and it
was pretty obvious that he was a gage-watcher. I
suggested to him that our little grass-patch was
both home to and a favorite nice-day-for-flying way
point for no radio airplanes.
I suggested that it was quite possible to safely
operate the airplane with only the occasional
glance at the gages . . . if at all. I got
the partial-panel covers out and covered up
ALL of the instruments in front of him and
suggested, "let's go flying".
We went around the patch a few more times while
I queried him about what he could hear and feel
from the airplane. I pointed out that the 150
could not be stalled if you can see the horizon
over the nose. The engine was impossible to
over-speed except in a dive. Suggested that
he put the nose on the horizon for climb-out.
We peeked under the IAS cover and yeah, not exactly
Vx but entirely satisfactory.
I demonstrated turning to final at pattern
altitude from 1/2 mile out. Throttle down,
hold level speed bleeds off then nose down
while milking the flaps down to full. Trim
down until you see that famous Cessna barn-door-
flaps picture out the windshield. Then
power up only as necessary to target
the numbers.
We did that a couple of times before we parked
and went into the office to get him on the
approved renters list. I suggested that he
practice those kinds of maneuvers himself
with the gages visible but glance at them
not so much with a notion of nailing the
numbers as maintaining a comfortable flight
condition . . . and paying attention to
what ELSE is going on outside.
The day I got my licence, the chief flight
instructor at United Beech was doing my
checkride. It was early Sunday morning with
very little traffic at KICT. We went to the
practice area to demonstrate the time-honored
basics and then headed for home. Half way
along the downwind he pulled the throttle
back and asked, "okay, now what?"
I asked the tower for and was granted
a short approach. The arrival with the runway
wasn't particularly graceful and hardly
a stabilized approach but the energy
budget for controlled flight was not
over drawn. He said, "I've seen better
but all-in-all, not bad". He signed off my
ticket on the taxi back to the ramp.
I didn't realize until years later what
an exceptional crew of instructors taught
out of United Beech on KICT. Yeah, there
are times when finely tuned numbers are
important . . . like when boring holes
in the crud. But those numbers are icing
on the cake for competent operation of
the airplane especially when dealing
with the unexpected . . . like when
that pretty glass screen goes dark . . .
okay, now what?
What you see, hear and feel are the ultimate
back-up system for avoiding bad days in the
cockpit.
Bob . . .
Un impeachable logic: George Carlin asked, "If black boxes
survive crashes, why don't they make the whole airplane
out of that stuff?"
Message 8
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| Subject: | Slickstart Current Draw update |
Hello,
Awhile back I mentioned my Slickstart unit that needed a 10amp fuse to
operate whereas the factory recommended fuse is 5 amp and current draw from
other users is much less.
The unit is installed on a LOM engine and was unused when I bought it
locally, the previous owner bought it for a project that never happened.
Other LOM users have reported no problems.
I sent the unit back to the Champion Aerospace and they reported that the
unit was manufactured in 1997 and that they tested it numerous times and
found nothing wrong.
I enquired how they test it and this is what they replied
"Mike, The ATP is a computer test of internal circuitry and output energy
and tests all the internals, none of these parts should deteriorate with
age."
Could someone with more insight please advise if I should accept this or
should I ask them to test it under "real" conditions
Thanks
Mike
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Message 9
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Hello All,
I'm new to the community and trying to come up with an electrical system design
I'm happy with for SDS EFI. I started with something based on Z-14, but with
modifications to make it suitable for SDS - this could be an entire separate
topic. I have since found Z101B and I really like it so far!
Has anyone implemented Z101B yet? I had a few questions about the design:
1. Has anyone tried to measure battery current instead of alternator current?
I'm guessing this won't work easily because there are too many fat wires to pass
through the hall effect sensor.
2. I noticed the aux alternator B-lead is always hot. This could cause the battery
to drain if one of the alternator diodes fails. I don't see a quick fix.
Any suggestions?
3. Any reason the functions of "alt bus" and "alt alternator" should be tied together?
Seems like they can be operated independently with separate switches
and doing so seems less confusing - for me at least.
4. I was planning to have the main bus in the cabin so I'll need to add an ANL
fuse between the battery contactor and main bus. I guess this is more of a comment
than a question. Along the same lines, shouldn't the brownout bus feed
through the contactor have an ANL fuse?
5. Any reason to not power the brownout booster from the starter side of the start
contactor? This would reduce the load being switched by the start button.
I really don't want those contacts to weld.
Any comments/suggestions appreciated. Thank you everyone!
-Patrick
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=499498#499498
Message 10
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| Subject: | Re: Dark and stormy night during CAVU |
>I have to find another method of picking up the rpm. I already have
>a reluctor. Just have to install it. But, a word to the wise. . .
>don't use the generator as a tachometer source. This is
>experimental aviation, and I consider this experiment to be a
>success. I learned something, and no metal was bent in the process.
Actually, gear driven pm alternators are FINE
rpm signal sources provided that the interface
between AC 'signal' from the alternator
has the right characteristics to drive the
tachometer.
The tachometer's installation instructions should
speak to voltages, waveforms and dc offsets
tolerated by the tachometer electronics. Of course,
there's the matter of scale factor . . . tach
signal events per engine revolution for the purposed
of calibrating the tach.
My FIRST choice for an electronic tachometer
signal source would be the PM alternator if
available. Three reasons:
(1) The AC frequency is dead nuts proportional
to engine rpm and . . .
(2) the 'signal' is sufficiently robust to
also be a POWER source for the tach and . . .
(3) that power source is ALWAYS there if the
engine is running.
Having said that, not every tach can exploit
any PM alternator as a signal/power source.
Do the homework. If the electron gods are
not insulted, you just might have an opportunity
for a reliable and robust tachometer.
Bob . . .
Un impeachable logic: George Carlin asked, "If black boxes
survive crashes, why don't they make the whole airplane
out of that stuff?"
Message 11
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| Subject: | Re: Switch Question |
That switch is available for $30 at Univair
https://www.univair.com/electrical-lighting/view-all/an3023-2-piper-switch/
Any snap action switch will work. The master contactor draws less than an amp.
Be sure to put a diode across the contactor coil to protect the switch from arcing.
The banded end of the diode connects to positive.
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=499500#499500
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| Subject: | Re: Switch Question |
At 10:33 AM 11/24/2020, you wrote:
>
>My master switch is specified as an AN 3023-2. I have been unable
>to find any documentation on just what that is, other than some type
>of DPST switch. Is there a source for decoding the AN switch specifications?
>
That is a vintage switch dating back to the 40's or earlier.
It's reminiscent of the master switch in a Piper TriPacer
I took dual in wwwaayyy back when. BEEFY switch, no battery
master relay.
They're still available as you can see here . . .
https://tinyurl.com/y57x62bp
What's your application?
Bob . . .
Un impeachable logic: George Carlin asked, "If black boxes
survive crashes, why don't they make the whole airplane
out of that stuff?"
Message 13
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| Subject: | Re: Z101B Questions |
Lots of builders measure battery current instead of alternator current.
Just don't measure starter motor current.
Most planes do not have fuses protecting the main power bus because a fuse
creates more of a hazard than than an unprotected bus and feeder. The pilot
can shut off the master battery contactor if necessary.
5. Yes, timing. The brownout booster needs to be powered up before the starter
contactor closes.
The more complicated the electrical system is, the more likely that something will
go wrong.
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=499502#499502
Message 14
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| Subject: | Re: Switch Question |
At 03:41 PM 11/24/2020, you wrote:
>At 10:33 AM 11/24/2020, you wrote:
>><faithvineyard@yahoo.com>
>>
>>My master switch is specified as an AN 3023-2. I have been unable
>>to find any documentation on just what that is, other than some
>>type of DPST switch. Is there a source for decoding the AN switch
>>specifications?
>>
>
> That is a vintage switch dating back to the 40's or earlier.
> It's reminiscent of the master switch in a Piper TriPacer
> I took dual in wwwaayyy back when. BEEFY switch, no battery
> master relay.
>
> They're still available as you can see here . . .
>
>https://tinyurl.com/y57x62bp
>
> What's your application?
>
P.S. I have confirmed that this switch was used on
Univair (ERCO) aircraft as the primary current
carrying device for ship's power. This IS a high
current switch . . . probably rated at 30A or more.
If that's how it's used in your application, suggest
you add a battery master contactor thus allowing
substitution of a friendlier toggle switch.
Bob . . .
Un impeachable logic: George Carlin asked, "If black boxes
survive crashes, why don't they make the whole airplane
out of that stuff?"
Message 15
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| Subject: | Re: Slickstart Current Draw update |
>
>"Mike, The ATP is a computer test of internal circuitry and output
>energy and tests all the internals, none of these parts should
>deteriorate with age."
>
>Could someone with more insight please advise if I should accept
>this or should I ask them to test it under "real" conditions
>
>Thanks
>
>Mike
Slick has been building these things for decades.
Don't know about their design and test policies
but the goal of an ATP is to confirm performance
to specs. Without seeing their test documentation,
we cannot know if it falls short of being 'real'
but I'd bet it's a rigorous test.
Bob . . .
Un impeachable logic: George Carlin asked, "If black boxes
survive crashes, why don't they make the whole airplane
out of that stuff?"
Message 16
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| Subject: | Re: Z101B Questions |
At 02:01 PM 11/24/2020, you wrote:
><panelsonms@hotmail.com>
>
>Hello All,
>I'm new to the community and trying to come up with an electrical
>system design I'm happy with for SDS EFI. I started with something
>based on Z-14, but with modifications to make it suitable for SDS -
>this could be an entire separate topic. I have since found Z101B
>and I really like it so far!
Welcome aboard my friend!
>Has anyone implemented Z101B yet? I had a few questions about the design:
>1. Has anyone tried to measure battery current instead of alternator current?
been there, done that, nobody does it any more . . . at least
not on single engine aircraft. Battery ammeter readings are
not helpful data in flight. In fact, the only ammeter I recall
being really useful on an SE aircraft was the A36 Bonanza with
prop de-ice. The system only powered one blade at a time
and having an ammeter in series with prop-deice would
offer a gross indication for loss of one heater circuit.
But then, you'd probably know something was out of whack
when prop balance was compromised due to ice accumulation
on one blade.
If I were going to fit an airplane with the single most
valuable indicator for loss of system performance
it would be ACTIVE NOTIFICATION of low volts. This
is something that requires pre-planned actions on
the part of a pilot. Ammeters are sort like fox-tails
on your antenna . . . or spinner hub caps.
> I'm guessing this won't work easily because there are too many fat
> wires to pass through the hall effect sensor.
How would you use those numbers if you had them?
>2. I noticed the aux alternator B-lead is always hot. This could
>cause the battery to drain if one of the alternator diodes fails. I
>don't see a quick fix. Any suggestions?
No fix necessary. Diodes just don't do that any
more and then it would require more than one to
cause a drain which would be mitigated by the b-lead
fuse.
>3. Any reason the functions of "alt bus" and "alt alternator"
>should be tied together? Seems like they can be operated
>independently with separate switches and doing so seems less
>confusing - for me at least.
They share a switch but are not 'tied' together. The switch
serves the same function as battery master . . . 3 position
switch that closes the relay first and alternator next.
>4. I was planning to have the main bus in the cabin so I'll need to
>add an ANL fuse between the battery contactor and main bus. I guess
>this is more of a comment than a question. Along the same lines,
>shouldn't the brownout bus feed through the contactor have an ANL fuse?
No, those are power distribution FAT wires. Those
are never fused in light aircraft. Probability of
a fault that puts a FAT wire at risk is nil. You can
add one if you wish but there's no foundation in
historical risk assessment that supports it.
>5. Any reason to not power the brownout booster from the starter
>side of the start contactor? This would reduce the load being
>switched by the start button. I really don't want those contacts to weld.
It's a function of timing. The brownout booster needs
to be spooled up and ready to take a load BEFORE
the battery is burdened with starter inrush current.
It's just milliseconds but they're important. If
you're worried about the starter switch then
do the load analysis to confirm the switch's
suitability to task.
Band-aids on worries are seldom a good thing . . .
modifications to meet requirements are never
a bad thing.
Bob . . .
Un impeachable logic: George Carlin asked, "If black boxes
survive crashes, why don't they make the whole airplane
out of that stuff?"
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| Subject: | Re: Dark and stormy night during CAVU |
> I have to find another method of picking up the rpm. I already have a reluctor.
Just have to install it. But, a word to the wise. . . don't use the generator
as a tachometer source. This is experimental aviation, and I consider this
experiment to be a success. I learned something, and no metal >was bent in the
process.
I have a couple of thoughts and some questions related to this post.
first the thoughts.
Is it possible the tachometer is wired on the wrong side of the regulator / rectifier?
I have as exhibits, three attached documents.
1) a similar tachometer circuit as shown in the Remaster electrical manual (i.e.
PM alternator with Westach, tachometer)
2) the Revmaster alternator connections as shown in their illustrious manual.
3) the alternator connections as I've redrawn them (after much noodling and consideration).
Recognizing that not all RR for PMA are created under the same zodiac. And, I'm
in the process of verifying the operation of the Revmaster as I've interpreted
and redrawn it.
I can imagine at least one RR design that would shunt the AC coils out when reaching
the setpoint, which would nullify the tach signal. The design of the Revmaster
(series regulator, in my personal venacular) does not shunt the PMA coils
but instead, opens the PM circuit when the battery voltage reaches a set
value (with an SCR that completes the PMA circuit to battery common). If the
tach is wired on the AC side of the RR, (as Revmaster shows it) the voltage signal
will still drive the tachometer when the RR reaches setpoint and opens the
circuit to the battery (as described by Bob, with plenty of extra power to spare).
Alternatively, if the tach is on the DC side of the RR, the signal is likely to
die out, as the RR intermitantly disconnects the PMA from the battery, as it
reaches the target voltage. Also, ( in the case of the Revmaster's dual alternar)
tif the "other" PMA is selected as the "chosen one" to supply power to the
battery and ships devices, the original (now disconnected) alternator will still
be available to run the tach, with the voltage pulses it is happily generating
at basically an "open circuit" voltage condition.
In the version (that I've not seen, but only heard of) where the PMA is short circuited
when reaching voltage setpoint, I can imagine that the tach connected
to the AC side would fail to sense any voltage as the RR reached setpoint. It
would seem that this design (a shunted PMA RR) would be very hard on the RR
as it has to reject the heat of full current and it's nominal voltage drop and
b) damn unnecessary added heat to the PMA as it generates near full short circuit
current across its coils.
Does the original post member have a circuit diagram and alternator we can evaluate?
Dan Theis
--------
Scratch building Sonex #1362
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=499506#499506
Attachments:
http://forums.matronics.com//files/revmaster_2300_rev13_alternator_ckt_190.pdf
http://forums.matronics.com//files/revmaster_manual_alternator_connection_492.pdf
http://forums.matronics.com//files/remaster_manual_tach_connection_377.pdf
Message 18
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| Subject: | Re: Switch Question |
My airplane is an Alon Aircoupe that Univair now has the TCSD for. It does not
have a battery master contactor, and the STC available to add one does not include
the Alons due to a change in the battery box and location. I am working
with my A&P/IA on a possible field approval, along with a lithium battery installation.
I was curious about the AN switch and what its characteristics are.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=499508#499508
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Nice Information Your first-class knowledge of this great job can become a suitable
foundation for these people. I did some research on the subject and found
that almost everyone will agree with your blog.
--------
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=499509#499509
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| Subject: | Slickstart Current Draw update |
Thanks for the help, I will keep you updated
Keep well
Mike
From: owner-aeroelectric-list-server@matronics.com
<owner-aeroelectric-list-server@matronics.com> On Behalf Of Robert L.
Nuckolls, III
Sent: November 24, 2020 4:06 PM
Subject: Re: AeroElectric-List: Slickstart Current Draw update
"Mike, The ATP is a computer test of internal circuitry and output energy
and tests all the internals, none of these parts should deteriorate with
age."
Could someone with more insight please advise if I should accept this or
should I ask them to test it under "real" conditions
Thanks
Mike
Slick has been building these things for decades.
Don't know about their design and test policies
but the goal of an ATP is to confirm performance
to specs. Without seeing their test documentation,
we cannot know if it falls short of being 'real'
but I'd bet it's a rigorous test.
Bob . . .
Un impeachable logic: George Carlin asked, "If black boxes
survive crashes, why don't they make the whole airplane
out of that stuff?"
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