Today's Message Index:
----------------------
1. 12:25 AM - Re: Load Analysis (Matt Prather)
2. 12:26 AM - Re: Re: Cessna SB on transients. (George Braly)
3. 05:46 AM - Ground Test???? (Eric Henson)
4. 05:50 AM - Re: HF meters (Chuck Jensen)
5. 05:54 AM - Re: Solid State Relays vs. Solenoids (John Schroeder)
6. 06:57 AM - Re: Solid State Relays vs. Solenoids (Glaeser, Dennis A)
7. 07:38 AM - Re: Cessna SB on transients. (Eric M. Jones)
8. 08:25 AM - Re: Engraved overlay and S700-2-10 terminals (Karen and Robert Brown)
9. 08:49 AM - More panel labels (Hinde, Frank George (Corvallis))
10. 09:08 AM - Re: Re: Solid State Relays vs. Solenoids (chad-c_sip@stanfordalumni.org)
11. 09:24 AM - Expensive switches??? (Hinde, Frank George (Corvallis))
12. 10:56 AM - Re: More panel labels (John Swartout)
13. 11:08 AM - Re: Re: Solid State Relays vs. Solenoids (Robert L. Nuckolls, III)
14. 11:54 AM - Re: More panel labels (Hinde, Frank George (Corvallis))
15. 12:26 PM - Re: Re: Cessna SB on transients. (Robert L. Nuckolls, III)
16. 12:32 PM - Re: More panel labels (EuropaXSA276@aol.com)
17. 01:03 PM - Re: More panel labels (Hinde, Frank George (Corvallis))
18. 02:29 PM - Re: Cessna SB on transients (repaired last paragraph) (Robert L. Nuckolls, III)
19. 02:32 PM - Re: Re: Solid State Relays vs. Solenoids (Robert L. Nuckolls, III)
20. 02:33 PM - Re: Solid State Relays vs. Solenoids (Robert L. Nuckolls, III)
21. 02:37 PM - Re: Re: Cessna SB on transients. (Robert L. Nuckolls, III)
22. 05:30 PM - Re: Panel vs Firewall Ground--do the (Robert L. Nuckolls, III)
23. 06:05 PM - Re: Panel vs Firewall Ground--do the electrons care? (Roger Evenson)
24. 06:12 PM - Re: Re: Solid State Relays vs. Solenoids (chad-c_sip@stanfordalumni.org)
25. 07:08 PM - Re: Panel vs Firewall Ground--do the (Robert L. Nuckolls, III)
26. 08:46 PM - Dynon D-10A Ticking (Jerry Isler)
27. 09:46 PM - Re: Dynon D-10A Ticking (chad-c_sip@stanfordalumni.org)
28. 11:31 PM - Re: Dynon D-10A Ticking (Werner Schneider)
Message 1
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| Subject: | Re: Load Analysis |
--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
I don't know much about thermo, but it seems like heat transfer through
conduction is at least as effective as through radiation and convection.
If a single wire in a bundle is being asked to carry lots of continuous
current, but the rest of the bundle only handles momentary loads, isn't it
possible that the bundle may be a cooler environment than in air?
Regards,
Matt-
VE N34RD, C150 N714BK
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
> <nuckollsr@cox.net>
>
> At 02:46 PM 5/19/2005 -0400, you wrote:
>
>>--> AeroElectric-List message posted by: Matt Jurotich
>><mjurotich@hst.nasa.gov>
>>
>>A small problem with your experiment. A single wire in air should
>> dissipate a lot of heat to the surrounding air. That same wire in the
>> middle of a wire bundle is going to get very much hotter. That is why
>> most in aerospace insist on significant derating.
>
> Not a problem at all. The experiment shows what the experiment shows
> . . . 20A through a 22AWG wire in free air runs at about 100C . . .
> WELL below the rating of the insulation. This speaks nothing to
> de-rating the wire for lots of reasons including voltage drop due to
> length, elevated temperature of the environment AND restriction of
> heat rejection capabilities due to bundling of
> the wire.
>
> I wasn't suggesting that one should even consider running 20A
> through a 22AWG wire as an installed equipment design goal. What I
> WAS suggesting is that folks who worry about wire behaving
> like fuses and breakers have mis-placed their concerns. The fusing
> constant (I-squared*T) for wire is many times that of a breaker and
> still more times that of most fuses. The notion that just because a
> 5A breaker opens pretty quickly at 10A somehow translates to a 22AWG
> wire treading up to the edge of destruction is a waste of worry
> resources.
>
> Wires installed and protected in accordance with the recommendations
> of AC43-13 or any other reference document are de-rated and VERY
> conservative with respect to risks to wire . . . the fact that
> circuit protection operates relatively quickly does not mean that
> the wire cheated death by a narrow margin.
>
> Bob. . .
>
>
Message 2
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| Subject: | Re: Cessna SB on transients. |
--> AeroElectric-List message posted by: "George Braly" <gwbraly@gami.com>
Bob,
I don't want to repeat the experiment.
But I did fry an encoding altimeter with an alternator load dump about six weeks
ago.
By choice, it is not repeatable. But it is first hand.
However, it is not a solenoid issue, which was the focus of your well stated message.
Regards, George
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III
Subject: AeroElectric-List: Re: Cessna SB on transients.
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>This is from 2002 ForPilots.com. I think it is of general interest to the
>discussion.
>
>My question is--Where do I get an online copy of the SB?
>
> > >(Mike wrote):
> > >The key to eliminating spike-induced damage to avionics and/or the OVP/VR
> > >is having said equipment off line at the instant the spikes are
>generated,
> > >and also by installing "catch" diodes across the starter and master
>solenoids,
> > >as well as having a "transorb" (MOV or Zener) across the main bus...
This is the standard mantra being propagated for over 4 decades.
Just enough science stirred together with lots of conjecture
to give it credibility.
> > Peter wrote:
> > Is there a US STC for these devices? Or are any "FAA-certified"? I am
> > in the UK and cannot do anything although if there is a STC the UK CAA
> > respects that (in trivial mods like this).
>
> >Cessna realized that they screwed up by producing aircraft from
> >the 1950s thru the 1980s with no catch diodes across the master,
> >starter, and external power solenoid, and they issued Service
> >Bulletins instructing owners to install a Cessna Part
> >No xxxxx diode(s) across the coils of the solenoid(s).
> >As I recall, the diodes turned out to be 1N4007...
"Screwed up"???? Cessna, like every other light airplane
company of the era installed the same components in their
airplanes as Ford and Chevy did in their cars. There was
no reason to treat the airplane different than any other
vehicle fitted with engine, generator/alternator and battery.
Until solid state devices showed up in airplanes in the early
60's there was no reason to be concerned or even investigate
inductive spikes from contactors. The radios were vacuum tube
and got high voltage from vibrator or dynamotor supplies. There
were no systems in the airplane that even MIGHT be vulnerable
to short duration, low energy transients.
> >My mechanic installed the diode per the service bulletin instructions
> >and maked a log entry "complied with SBxxxx" in the airfame log.
>
> >In the US, an AP mechanic can also make a "minor" mod, like adding a
> >transorb or a catch diode, and just make a log entry to return the
> >aircraft to service. My mechanic let me install other spike
> >catching components, and then just took care of the logs.
>
> >The spikes I recorded in my 1968 Skylane (14V) during cranking,
> >(prior to installing a catch diode across the starter solenoid)
> >were more than 400 V peak to peak, sort of a highly-damped sine
> >wave, that lasted about 10msec. My Skylane came out of the factory
> >with a catch diode on the master solenoid, but not on the aux
> >power solenoid or the starter solenoid.
Measured where? I've measured and demonstrated the high
voltage spiking capability of contactors and written about them
in detail. See:
http://aeroelectric.com/articles/spikecatcher.pdf
This same article speaks to the error in an original issue
of an AD against the ACS/Gerdes 510 ignition switch where
the diode was installed in the wrong place to protect the
switch. I note that later issues correct this error. I need
to update that article.
I was at Cessna when our chief scientist, Dr. Gordon Wood
purchased a brand new, Hewlett-Packard peak reading voltmeter.
We were all amazed at readings we got off the coils of starter
and battery master contactor coils. Gordon's work prompted us
to research available silicon diodes and device suitable means
for installing them on production aircraft. I seem to recall the
little 1N2070 plastic "bullet" being selected to install on strip
of phenolic with eyelets in each end to facilitate attachment of
PIDG terminated wires with screws. See . . . even in 1965 we were
wrestling with those little leaded critters to figure out a
good way to mount them.
So, the statement about Cessna's "screw up" is a product of
somebody's uninformed rhetoric. What the author does not point
out and Gordon Wood measured was that such spikes DO NOT propagate
to the bus. Yes, we could put the voltmeter on the un-suppressed
contactor coil and get readings that would impress even Nicky Tesla
but those energies were dissipated 99%+ in arcing at the
controlling switch. Remnants that showed up on the bus were very
short (microseconds), heavily loaded by system dynamic impedance
consisting of battery, capacitors on inputs to electronics, and
any equipment turned on, etc.
We knew in 1965 that starter and battery master contactor
spikes were not a risk to any other parts of the airplane
beyond the controlling switches. We also knew that bus
voltage transients due to starter activity were well inside
the range of bus voltages expected by the designers of the
radios.
Capacitors charged up to some value and then discharged to
a bus can deliver LOTS of current for a short time but a a
voltage no higher than they were charged with in the first
place. Inductors can deliver LOTS of volts for a short time
but at a current no greater than they were initially charged
with. Okay, it takes a 1A source to close a battery contactor.
Discharging a short (milliseconds), 1A constant current source
of any voltage into the bus is a non-event. Starter contactors
are a bit meaner, perhaps 4-5 amps. But still, no big deal with
a battery on line.
The NUMBER ONE reason for installing catch diodes was to
protect switch contacts and not to save overly delicate avionics
from the occasional transient that was WELL inside DO-160 limits.
I am still looking for the repeatable experiment that demonstrates
even a small fraction of the risks and worries that are freely
circulated amongst folks who claim to know how dangerous it is
out there in the "spike" jungle. There are folks who would have
you sprinkle little spike catchers all over the airplane and
there are those who still worship at the altar of avionics
master switches an cringe at the thought of hitting the system
with starter currents. I've taken more starting event traces
off the bus of cars, light planes and biz jets than I can count
and I've yet to catch one of the evil critters in the wild.
And to date, no one has answered my challenge to produce
a trace from a repeatable experiment that demonstrates their
existence. It's always been, "My brother-in-law's cousin has
a next door neighbor who knows a guy at the airport who melted
his whole stack of avionics to the ground 'cause he . . .
(1) left the avionics master on
(2) didn't install certain kinds of "protection"
(3) etc.
(4) etc.
Until such data comes forward, I have to advise that I have 40 years
experience, analysis and data that argues against the majority of the
dogma being preached with respect to transients and bus quality
and ZERO supporting data from anyone to the contrary.
Bob . . .
---
---
Message 3
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--> AeroElectric-List message posted by: "Eric Henson" <ehenson@teamhorner.com>
Bob, is it possible to test your airframe ground? I hooked my B&C grounding strap
to the 1/4" bolts on my prop gov boss (Its blanked off, not using the governor).
I'm suspicious because the boss is removable, which means its separated
from the accessory case by two gaskets. Does the current just run through the
steel stud/nut connection?
Any way I can test it before I fry a radio?
Thanks as always
Eric Henson
RV-6 in perpetuity
Message 4
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--> AeroElectric-List message posted by: "Chuck Jensen" <cjensen@dts9000.com>
Hal,
I also have a Skymap that I'm going to get around to selling as I replaced it with
a UPSat 80 (ne: Garmin 480), but the Skymap was, and still is, a very nice
VFR instrument. I'm not sure how the screen plugs into the electronics but you
might try disconnecting the screen, cleaning the male/female contact surfaces
and put it back together. Sometimes the connectors will corrode a little and
lose contact, resulting in the symptoms you are seeing. Its' worth a try.
Chuck
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Hal
Kempthorne
Subject: Re: AeroElectric-List: HF meters
--> AeroElectric-List message posted by: Hal Kempthorne <hal_kempthorne@sbcglobal.net>
My old British Skymap non-color has developed some blank lines making it nearly
unusable. King now services these but not in an economically sane way. They
suggested contacting the Brits. I sent them email but no response. I suspect
they too want no part of it. My fear is that if I fix it, a different part
will fail.
Do any of you have any ideas of what to do with this once fabulous device? I mean,
besides chuck it in the dumpster or sell it 'as is' on ebay?
hal
Message 5
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| Subject: | Re: Solid State Relays vs. Solenoids |
--> AeroElectric-List message posted by: "John Schroeder" <jschroeder@perigee.net>
Bob -
What does one of these critters cost and are they available to the OBAM
community?
Thanks,
John
Tue, 24 May 2005 21:50:00 -0500, Robert L. Nuckolls, III
<nuckollsr@cox.net> wrote:
> We use solid state contactors in our most demanding situations. Here's a
> relay
> I helped develop for the tail de-ice system in a Beechjet.
> http://www.aeroelectric.com/Pictures/Solid_State_100A_Contactor.jpg
--
Message 6
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| Subject: | Re: Solid State Relays vs. Solenoids |
--> AeroElectric-List message posted by: "Glaeser, Dennis A" <dennis.glaeser@eds.com>
These aren't the ones Bob references, but Eric Jones has a couple of
solid-state relays on his website:
35-50 amps for $35 - http://www.periheliondesign.com/powerlinkjr.htm
A bigger one for $99 - http://www.periheliondesign.com/moreproducts.htm
(Eric's gotta approve your application)
I also checked Digikey for the Crydom D60D devices (60+ amps) and they
run $83 and up (unless you buy in bulk).
It will be interesting to see the price of the certified item...
Dennis Glaeser
--> AeroElectric-List message posted by: "John Schroeder"
Bob - What does one of these critters cost and are they available to the
OBAM community?
Thanks,
John
Message 7
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| Subject: | Re: Cessna SB on transients. |
--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<nuckollsr@cox.net>
> >My question is--Where do I get an online copy of the SB?
Same question: Where do I get an online copy of the SB?
> > > >as well as having a "transorb" (MOV or Zener) across the main bus...
>
> This is the standard mantra being propagated for over 4 decades.
> Just enough science stirred together with lots of conjecture
> to give it credibility.
>
> > > Peter wrote:
> > > Is there a US STC for these devices? Or are any "FAA-certified"? I am
> > > in the UK and cannot do anything although if there is a STC the UK CAA
> > > respects that (in trivial mods like this).
> >
> > >Cessna realized that they screwed up by producing aircraft from
> > >the 1950s thru the 1980s with no catch diodes across the master,
> > >starter, and external power solenoid, and they issued Service
> > >Bulletins instructing owners to install a Cessna Part
> > >No xxxxx diode(s) across the coils of the solenoid(s).
> > >As I recall, the diodes turned out to be 1N4007...
>
> "Screwed up"???? Cessna, like every other light airplane
> company of the era installed the same components in their
> airplanes as Ford and Chevy did in their cars. There was
> no reason to treat the airplane different than any other
> vehicle fitted with engine, generator/alternator and battery.
>
> Until solid state devices showed up in airplanes in the early
> 60's there was no reason to be concerned or even investigate
> inductive spikes from contactors. The radios were vacuum tube
> and got high voltage from vibrator or dynamotor supplies. There
> were no systems in the airplane that even MIGHT be vulnerable
> to short duration, low energy transients.
Absolutely true. The design of electronics went through a learning curve in
the transition to solid state. It was a while before enough analysis was
done to determine that voltage transients that were previously no problem
now had to be controlled. Perhaps Cessna didn't "screw up" and the SB's were
just a modification to update the system.
> > >......The spikes I recorded in my 1968 Skylane (14V) during cranking,
> > >(prior to installing a catch diode across the starter solenoid)
> > >were more than 400 V peak to peak, sort of a highly-damped sine
> > >wave, that lasted about 10msec. My Skylane came out of the factory
> > >with a catch diode on the master solenoid, but not on the aux
> > >power solenoid or the starter solenoid.
>
> Measured where? I've measured and demonstrated the high
> voltage spiking capability of contactors and written about them
> in detail. See:
>
> http://aeroelectric.com/articles/spikecatcher.pdf
>
> This same article speaks to the error in an original issue
> of an AD against the ACS/Gerdes 510 ignition switch where
> the diode was installed in the wrong place to protect the
> switch. I note that later issues correct this error. I need
> to update that article.
>
> ......... So, the statement about Cessna's "screw up" is a product of
> somebody's uninformed rhetoric. What the author does not point
> out and Gordon Wood measured was that such spikes DO NOT propagate
> to the bus. Yes, we could put the voltmeter on the un-suppressed
> contactor coil and get readings that would impress even Nicky Tesla
> but those energies were dissipated 99%+ in arcing at the
> controlling switch. Remnants that showed up on the bus were very
> short (microseconds), heavily loaded by system dynamic impedance
> consisting of battery, capacitors on inputs to electronics, and
> any equipment turned on, etc.
>
> We knew in 1965 that starter and battery master contactor
> spikes were not a risk to any other parts of the airplane
> beyond the controlling switches. We also knew that bus
> voltage transients due to starter activity were well inside
> the range of bus voltages expected by the designers of the
> radios.
>
> Capacitors charged up to some value and then discharged to
> a bus can deliver LOTS of current for a short time but a a
> voltage no higher than they were charged with in the first
> place. Inductors can deliver LOTS of volts for a short time
> but at a current no greater than they were initially charged
> with. Okay, it takes a 1A source to close a battery contactor.
> Discharging a short (milliseconds), 1A constant current source
> of any voltage into the bus is a non-event. Starter contactors
> are a bit meaner, perhaps 4-5 amps. But still, no big deal with
> a battery on line.
>
> The NUMBER ONE reason for installing catch diodes was to
> protect switch contacts and not to save overly delicate avionics
> from the occasional transient that was WELL inside DO-160 limits.
>
> I am still looking for the repeatable experiment that demonstrates
> even a small fraction of the risks and worries that are freely
> circulated amongst folks who claim to know how dangerous it is
> out there in the "spike" jungle. There are folks who would have
> you sprinkle little spike catchers all over the airplane and
> there are those who still worship at the altar of avionics
> master switches ..........
>
> ....Until such data comes forward, I have to advise that I have 40
years
> experience......
........Activities include: Teaching gophers to dig postholes and roping
whole herds of cattle at a time. Rode everything in the West, including a
mountain lion and a cyclone. Horse was named "Widow Maker". Drinks his
whiskey with fishhooks and nitroglycerin.......
Dear Bob,
Dr. Woods tests may or may not have been correct and applicable to all
situations. What was true for the metal airplanes with production-line
electrical systems may or may not be true for the Owner Built And Maintained
product. What was true in 1965 should certainly be re-examined in light of
new equipment and new technology. Science involves the perpetual
re-examination of what we believe is true, but now we can look closer.
My reason for posting this old email about an even older subject is to bring
up the subject of damping transients at the starter solenoid, contactor and
motor. These are areas that require attention EVEN IF NOBODY CAN PRODUCE A
TEST THAT SAYS SO---just because allowing transients on the bus is poor
engineering de facto.
What's the likely outcome of damping transients with a sprinking of
Transient Voltage Suppressors?
1) Greater reliability (but we don't know how much)
2) Greater survivability in lightning (Those avionics shops get rich...).
3) Reduced noise in the headphones (We don't know how much...but your Rx and
Tx range improves as a bonus...but we don't know how much)
4) A better quality product (but we don't know how much).
The argument here is--Just what is good engineering practice? Demanding that
one show proof that a certain TVS is needed is silly. Circuit boards are
sprinkled with 0.1 caps....can you prove that they are really needed? Much
electronic assembly is done with ESD control--is this really needed if it is
raining outside? Prove it....It is easy to produce an infinite number items
for which proof is an utter impossibility (Godel). Since voltage transients
are so sensitive to conditions, what was true of a 1965 Cessna 150 with
particular equipment has little relevance. Even today it is a real trick to
show spikes that will wipe out some electronics. Can you show that the
"forest of tabs" grounding is really necessary? In all cases? But it's
certainly best practice.
A lot of engineering is just a kind of aesthetic bet. You do some things
because it prevents uncontrollable factors from getting out of hand. You
cannot analyze everything. Especially if you make just ONE.
I am still working on Z100. It has sufficient TVS's to guarantee that the B+
and ground are never more than 18V from each other. Can I prove this is
needed? Not at all, but when that lightning bolt strikes a pole 300 feet
from my parked Glastar someday in Guadeloupe (the Caribbean French Hawaii),
I may not be spending any euros at the non-English-speaking avionics shop.
That's my bet.
I'd still like to see those SB's
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
Phone (508) 764-2072
Email: emjones@charter.net
"Democracy is the theory that the common people know what they want and
deserve to get it good and hard." -- H. L. Mencken
Message 8
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| Subject: | Re: Engraved overlay and S700-2-10 terminals |
--> AeroElectric-List message posted by: "Karen and Robert Brown" <bkbrown@ashcreekwireless.com>
For another idea, FASTsigns will make up rub-on labels (using individual letters)
in any font/color. I used this stuff on an exterior door for 10 years and
it didn't fade or come off with daily abuse from customers...
just a thought...
Bob Brown
RV7A - gluing rear canopy skirts
Message 9
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| Subject: | More panel labels |
--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com>
Another way...its still working great after 6 years...is to make your
own labels on MS Word and print them on the large label sheets...It
think they may even have an exterior grade film/adhesive?...hmm can't
quite remember.
Anyway, print your own labels, any font any colour and print them on
clear and go stick 'em on. They look great as long as you put a box
around the text...razor blade to the edge of the box and you won't see
the edge of the label.
The great thing about this is you can then save the files and if your
labels ever peeled up...Just print of the file and voila you have a new
set...:)
Frank
Message 10
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| Subject: | Re: Solid State Relays vs. Solenoids |
Z-USANET-MsgId: XID168JeyqHs0336X38
--> AeroElectric-List message posted by: chad-c_sip@stanfordalumni.org
I don't see companies like Crydom being all that excited to certify their
components. They sell millions every year to industry and they change specs.
almost every year. Perhaps I'm wrong and there are some MOSFET relays that are
certified, but Im guessing they'd be obselete within a year or two.
Yes, these devices are a bit pricier than solenoids. But I only need about 4
in the plane. And when you consider that the input (control) current runs only
a few milliamps the actual abuse on the switch is very, very small. Certainly
less need to select very expensive switches now.
Chad
Chad Sipperley
Lancair IVP - turbine
Phoenix, AZ
>
> I also checked Digikey for the Crydom D60D devices (60+ amps) and they
> run $83 and up (unless you buy in bulk).
>
> It will be interesting to see the price of the certified item...
>
> Dennis Glaeser
>
Message 11
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| Subject: | Expensive switches??? |
--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com>
Expensive switches...Hmmm
I bought my switches 6 years ago from my local automotive store...Now I
did not select the cheesy plastic toggled...not sure if its on or off
type switch. 360 hours and not one of my switches has failed.
These have a nice snap and have chrome toggles...But were only a couple
of bucks each...rated to 10A DC.
Right now I see no reason not to install them on my new RV project?
Frank
Message 12
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| Subject: | Re: More panel labels |
--> AeroElectric-List message posted by: John Swartout <jgswartout@earthlink.net>
Frank, do those labels require a very SMOOTH, --maybe even glossy--paint surface
to adhere well?
-----Original Message-----
From: "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com>
Subject: AeroElectric-List: More panel labels
--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com>
Another way...its still working great after 6 years...is to make your
own labels on MS Word and print them on the large label sheets...It
think they may even have an exterior grade film/adhesive?...hmm can't
quite remember.
Anyway, print your own labels, any font any colour and print them on
clear and go stick 'em on. They look great as long as you put a box
around the text...razor blade to the edge of the box and you won't see
the edge of the label.
The great thing about this is you can then save the files and if your
labels ever peeled up...Just print of the file and voila you have a new
set...:)
Frank
Message 13
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| Subject: | Re: Solid State Relays vs. Solenoids |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 09:07 AM 5/25/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: chad-c_sip@stanfordalumni.org
>
>I don't see companies like Crydom being all that excited to certify their
>components. They sell millions every year to industry and they change specs.
>almost every year. Perhaps I'm wrong and there are some MOSFET relays that are
>certified, but Im guessing they'd be obselete within a year or two.
>
>Yes, these devices are a bit pricier than solenoids. But I only need about 4
>in the plane. And when you consider that the input (control) current runs only
>a few milliamps the actual abuse on the switch is very, very small. Certainly
>less need to select very expensive switches now.
Actually, when you use a switch to drive a very low control current,
you're more likely to get a failure because of TOO LITTLE current than
for too much. The last switch problem I encountered on a Beechjet was
a $high$ switch that carried only a few milliamps of current. The switch
went effectively open after about 10 years in service and having been
physically operated perhaps a few dozen times over that period.
Similarly, a C-150 I used to rent suffered the FIRST failure of
a factory installed 69-cent rocker switch after nearly 30 years
in service. It was the DOME light switch. Seldom used, low current.
I swapped it with the landing light switch and both system became
operable.
If your only reason for installing solid state contactors is to
improve on switch life, you may be disappointed. I strive for low
cost of ownership. Select parts which are capable, easily replaced
and reasonably priced. If you design your system for failure TOLERANCE,
parts are not hard to replace and don't drive you into sticker
shock . . . then you'll have an airplane you enjoy owning and never
surprises you.
That's why I've stuck with the $LOW$ contactors in my recommendations,
the next step up is MUCH more expensive and not likely to offer
performance that equates to lower cost of ownership. If you had
a Rotax alternator with only 18A of output, then some form of
solid state contactor might be attractive for a battery master
just to conserve on a limited energy supply . . . but a manual
battery master is simpler yet and MORE energy efficient than
a solid state contactor . . .
Bob . . .
Message 14
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| Subject: | More panel labels |
--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com>
I just used a rattle can to put three coats of smooth paint on the
panel....I think if you hade a wrinkle finish it might not stick so
well.
Wouldn't say my panel was glossy it's a little flatter than that...I
think I painted it with Krylon or something?
Frank
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of John
Swartout
Subject: Re: AeroElectric-List: More panel labels
--> AeroElectric-List message posted by: John Swartout
--> <jgswartout@earthlink.net>
Frank, do those labels require a very SMOOTH, --maybe even glossy--paint
surface to adhere well?
-----Original Message-----
From: "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com>
Subject: AeroElectric-List: More panel labels
--> AeroElectric-List message posted by: "Hinde, Frank George
--> (Corvallis)" <frank.hinde@hp.com>
Another way...its still working great after 6 years...is to make your
own labels on MS Word and print them on the large label sheets...It
think they may even have an exterior grade film/adhesive?...hmm can't
quite remember.
Anyway, print your own labels, any font any colour and print them on
clear and go stick 'em on. They look great as long as you put a box
around the text...razor blade to the edge of the box and you won't see
the edge of the label.
The great thing about this is you can then save the files and if your
labels ever peeled up...Just print of the file and voila you have a new
set...:)
Frank
Message 15
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| Subject: | Re: Cessna SB on transients. |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>
> > ....Until such data comes forward, I have to advise that I have 40
>years
> > experience......
>
>........Activities include: Teaching gophers to dig postholes and roping
>whole herds of cattle at a time. Rode everything in the West, including a
>mountain lion and a cyclone. Horse was named "Widow Maker". Drinks his
>whiskey with fishhooks and nitroglycerin.......
>
>Dear Bob,
>
>Dr. Woods tests may or may not have been correct and applicable to all
>situations. What was true for the metal airplanes with production-line
>electrical systems may or may not be true for the Owner Built And Maintained
>product. What was true in 1965 should certainly be re-examined in light of
>new equipment and new technology. Science involves the perpetual
>re-examination of what we believe is true, but now we can look closer.
Absolutely. So run out a plot of what you've observed and share
it with us.
>My reason for posting this old email about an even older subject is to bring
>up the subject of damping transients at the starter solenoid, contactor and
>motor. These are areas that require attention EVEN IF NOBODY CAN PRODUCE A
>TEST THAT SAYS SO---just because allowing transients on the bus is poor
>engineering de facto.
So if nobody has produced a test, we act on the seriousness
of the allegation?
>What's the likely outcome of damping transients with a sprinking of
>Transient Voltage Suppressors?
>
>1) Greater reliability (but we don't know how much)
>2) Greater survivability in lightning (Those avionics shops get rich...).
>3) Reduced noise in the headphones (We don't know how much...but your Rx and
>Tx range improves as a bonus...but we don't know how much)
>4) A better quality product (but we don't know how much).
>
>The argument here is--Just what is good engineering practice? Demanding that
>one show proof that a certain TVS is needed is silly. Circuit boards are
>sprinkled with 0.1 caps....can you prove that they are really needed? Much
>electronic assembly is done with ESD control--is this really needed if it is
>raining outside? Prove it....It is easy to produce an infinite number items
>for which proof is an utter impossibility (Godel). Since voltage transients
>are so sensitive to conditions, what was true of a 1965 Cessna 150 with
>particular equipment has little relevance. Even today it is a real trick to
>show spikes that will wipe out some electronics. Can you show that the
>"forest of tabs" grounding is really necessary? In all cases? But it's
>certainly best practice.
>A lot of engineering is just a kind of aesthetic bet. You do some things
>because it prevents uncontrollable factors from getting out of hand. You
>cannot analyze everything. Especially if you make just ONE.
I belive it was Lord Kelvin who suggested:
"When you can measure what you are speaking about, and express
it in numbers, you know something about it; but when you cannot
measure it, when you cannot express it in numbers, your knowledge
is of a meager and unsatisfactory kind: it may be the beginning
of knowledge, but you have scarcely, in your thoughts, advanced
to the stage of science."
If we're attempting to discuss a phenomenon that cannot be
quantified because no one has been able to or has attempted
to measure it, then the term "best practice" has no meaning.
It's no trick at all to identify, quantify and mitigate
ANY stimulus that might be damaging to ANY component and
deal with it in terms of the physics and present technologies.
We do it all the time in certified aviation. It does require
an understanding of all the physics involved and an effort
to verify your designs both in the lab and marketplace.
Granted, it may be simpler to apply liberal prophylactic
measures . . . after all, the excess devices don't "hurt"
anything. I know folks who have lots of bottles of stuff
from the health food stores who claim some benefit for
having consumed the contents . . . but if this is "good"
would it not be "better" to have one of every product?
Perhaps one could achieve physiological Utopia and require
no other sustenance than to consume a little bit of everything
"good".
>I am still working on Z100. It has sufficient TVS's to guarantee that the B+
>and ground are never more than 18V from each other. Can I prove this is
>needed? Not at all, but when that lightning bolt strikes a pole 300 feet
>from my parked Glastar someday in Guadeloupe (the Caribbean French Hawaii),
>I may not be spending any euros at the non-English-speaking avionics shop.
When you're establishing a new paradigm wherein the design
goal is to bound all activity on the bus between 0 and 18
volts, then we're not talking about "best" practice but
a "new" practice . . . which is just fine. But let us
make clear distinctions between what is NECESSARY
to live under the new and old paradigms and be prepared
to evaluate the cost of ownerships of each.
MOST important, let us take care not to market a new
paradigm with any manner of scare tactics, unsubstantiated
rumors or over enthusiastic allegations. There's tons of
that going on virtually every other Internet aviation
resource.
We owe it to our readers here on the List to sell good
with an interest can understand and MEASURE if they
so choose . . . after we show them how we measured it.
Bob . . .
Message 16
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| Subject: | Re: More panel labels |
--> AeroElectric-List message posted by: EuropaXSA276@aol.com
In a message dated 5/25/2005 1:35:57 PM Central Standard Time,
frank.hinde@hp.com writes:
Anyway, print your own labels, any font any color and print them on
Clear and go stick 'em on. They look great as long as you put a box
around the text...razor blade to the edge of the box and you won't see
The edge of the label.
I tried this once on my old Cherokee. The problem was that when I cleaned the
instrument panel the label would smudge. I think that HP ink must be water
based.
To remedy I took a second clear label and put it over the printed one.
Worked great.
Brian Skelly
Texas
Europa # A276 TriGear
See My build photos at:
http://www.europaowners.org/BrianS
Message 17
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| Subject: | More panel labels |
--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com>
I think you may have used the wrong cartridge...I think image permamence
might be much better using a photo cartridge.
Either that or just don't clean the panel...I never have...:)
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
EuropaXSA276@aol.com
Subject: Re: AeroElectric-List: More panel labels
--> AeroElectric-List message posted by: EuropaXSA276@aol.com
In a message dated 5/25/2005 1:35:57 PM Central Standard Time,
frank.hinde@hp.com writes:
Anyway, print your own labels, any font any color and print them on
Clear and go stick 'em on. They look great as long as you put a box
around the text...razor blade to the edge of the box and you won't see
The edge of the label.
I tried this once on my old Cherokee. The problem was that when I
cleaned the
instrument panel the label would smudge. I think that HP ink must be
water
based.
To remedy I took a second clear label and put it over the printed one.
Worked great.
Brian Skelly
Texas
Europa # A276 TriGear
See My build photos at:
http://www.europaowners.org/BrianS
Message 18
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| Subject: | Re: Cessna SB on transients (repaired last paragraph) |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 02:26 PM 5/25/2005 -0500, you wrote:
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<nuckollsr@cox.net>
>
> > ....Until such data comes forward, I have to advise that I have 40
>years
> > experience......
>
>........Activities include: Teaching gophers to dig postholes and roping
>whole herds of cattle at a time. Rode everything in the West, including a
>mountain lion and a cyclone. Horse was named "Widow Maker". Drinks his
>whiskey with fishhooks and nitroglycerin.......
>
>Dear Bob,
>
>Dr. Woods tests may or may not have been correct and applicable to all
>situations. What was true for the metal airplanes with production-line
>electrical systems may or may not be true for the Owner Built And Maintained
>product. What was true in 1965 should certainly be re-examined in light of
>new equipment and new technology. Science involves the perpetual
>re-examination of what we believe is true, but now we can look closer.
Absolutely. So run out a plot of what you've observed and share
it with us.
>My reason for posting this old email about an even older subject is to bring
>up the subject of damping transients at the starter solenoid, contactor and
>motor. These are areas that require attention EVEN IF NOBODY CAN PRODUCE A
>TEST THAT SAYS SO---just because allowing transients on the bus is poor
>engineering de facto.
So if nobody has produced a test, we act on the seriousness
of the allegation?
>What's the likely outcome of damping transients with a sprinking of
>Transient Voltage Suppressors?
>
>1) Greater reliability (but we don't know how much)
>2) Greater survivability in lightning (Those avionics shops get rich...).
>3) Reduced noise in the headphones (We don't know how much...but your Rx and
>Tx range improves as a bonus...but we don't know how much)
>4) A better quality product (but we don't know how much).
>
>The argument here is--Just what is good engineering practice? Demanding that
>one show proof that a certain TVS is needed is silly. Circuit boards are
>sprinkled with 0.1 caps....can you prove that they are really needed? Much
>electronic assembly is done with ESD control--is this really needed if it is
>raining outside? Prove it....It is easy to produce an infinite number items
>for which proof is an utter impossibility (Godel). Since voltage transients
>are so sensitive to conditions, what was true of a 1965 Cessna 150 with
>particular equipment has little relevance. Even today it is a real trick to
>show spikes that will wipe out some electronics. Can you show that the
>"forest of tabs" grounding is really necessary? In all cases? But it's
>certainly best practice.
>A lot of engineering is just a kind of aesthetic bet. You do some things
>because it prevents uncontrollable factors from getting out of hand. You
>cannot analyze everything. Especially if you make just ONE.
I belive it was Lord Kelvin who suggested:
"When you can measure what you are speaking about, and express
it in numbers, you know something about it; but when you cannot
measure it, when you cannot express it in numbers, your knowledge
is of a meager and unsatisfactory kind: it may be the beginning
of knowledge, but you have scarcely, in your thoughts, advanced
to the stage of science."
If we're attempting to discuss a phenomenon that cannot be
quantified because no one has been able to or has attempted
to measure it, then the term "best practice" has no meaning.
It's no trick at all to identify, quantify and mitigate
ANY stimulus that might be damaging to ANY component and
deal with it in terms of the physics and present technologies.
We do it all the time in certified aviation. It does require
an understanding of all the physics involved and an effort
to verify your designs both in the lab and marketplace.
Granted, it may be simpler to apply liberal prophylactic
measures . . . after all, the excess devices don't "hurt"
anything. I know folks who have lots of bottles of stuff
from the health food stores who claim some benefit for
having consumed the contents . . . but if this is "good"
would it not be "better" to have one of every product?
Perhaps one could achieve physiological Utopia and require
no other sustenance than to consume a little bit of everything
"good".
>I am still working on Z100. It has sufficient TVS's to guarantee that the B+
>and ground are never more than 18V from each other. Can I prove this is
>needed? Not at all, but when that lightning bolt strikes a pole 300 feet
>from my parked Glastar someday in Guadeloupe (the Caribbean French Hawaii),
>I may not be spending any euros at the non-English-speaking avionics shop.
When you're establishing a new paradigm wherein the design
goal is to bound all activity on the bus between 0 and 18
volts, then we're not talking about "best" practice but
a "new" practice . . . which is just fine. But let us
make clear distinctions between what is NECESSARY
to live under the new and old paradigms and be prepared
to evaluate the cost of ownerships of each.
MOST important, let us take care not to market a new
paradigm with any manner of scare tactics, unsubstantiated
rumors or over enthusiastic allegations. There's tons of
that going on virtually every other Internet aviation
resource.
We owe it to our readers here on the List to sell good
ideas and products founded on simple-ideas that anyone
with an interest can understand and MEASURE if they
so choose . . . after we show them how we measured it.
Bob . . .
Message 19
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| Subject: | Re: Solid State Relays vs. Solenoids |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>
>It will be interesting to see the price of the certified item...
>
> Dennis Glaeser
The one I illustrated is in the neighborhood of $2700 each
out the factory door. A non certified device could be sold
in volume for about $500.
Bob . . .
Message 20
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| Subject: | Re: Solid State Relays vs. Solenoids |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 08:54 AM 5/25/2005 -0400, you wrote:
>--> AeroElectric-List message posted by: "John Schroeder"
><jschroeder@perigee.net>
>
>Bob -
>
>What does one of these critters cost and are they available to the OBAM
>community?
Sure, he'd sell you one . . . but it's 28v only and the overhead
for qualifying to get on certified machines is staggering. I'd
guess they're about $2700.
Bob . . .
Message 21
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| Subject: | Re: Cessna SB on transients. |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 06:55 PM 5/24/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: "George Braly" <gwbraly@gami.com>
>
>Bob,
>
>I don't want to repeat the experiment.
>
>But I did fry an encoding altimeter with an alternator load dump about six
>weeks ago.
>
>By choice, it is not repeatable. But it is first hand.
>
>However, it is not a solenoid issue, which was the focus of your well
>stated message.
>
>Regards, George
Yup, once the battery is off line, all bets are off for
things not rigorously qualified for standing off the big
transients. The battery is still our most robust and reliable
firewall against such unhappy experiences.
Bob . . .
Message 22
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| Subject: | Re: Panel vs Firewall Ground--do the |
electrons care?
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
electrons care?
At 06:35 PM 5/24/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: "Roger Evenson"
><revenson@comcast.net>
>
>Just read Bob's new chapter on Audio Systems. Given that a single-point
>ground system is best to eliminate noise from ground loops, I don't
>understand the rationale for a separate audio ground near the radio
>stack. Why is it considered poor practice to run both audio and all other
>aircraft equipment grounds to a single firewall ground block?
good question. Ground LOOPS are defined as two or more grounds
for a single system or appliance. For example, fuel gages get into
trouble when the "sender" grounds in the wing and the instrument
grounds behind the panel. Radios or intercoms get noisy when headset
or microphone leads ground out on the airframe while the electronics
for the system ground elsewhere. The critical single point ground is
for all grounds needed for each system or appliance.
>Further, what's the difference between a single firewall ground for
>everything and a panel ground with a wire connecting the panel ground to
>the firewall ground? Does it matter to the audio system?
One would like to minimize the numbers and lengths of wires in
the whole aircraft . . . panels tend to have lots of grounding
requirements for instruments, lighting, audio systems and individual
radios. The avionics ground block offers an opportunity to
convert your entire panel assembly into a single appliance
by offering a local ground for all panel mounted accessories
and extending that as a robust, high quality ground (relatively
fat wires) to the firewall ground. You're still observing the
necessity for making all grounds for any one system (or related
systems like radios and audio system) at a single location and
then extending that location down to the firewall on a few
wires. This can have a marked effect on size of wire bundles and
on convenience of fabrication and installation.
We do this in big airplanes too . . . their are MULTIPLE single
point grounds scattered about a biz jet . . . the designer's
rules dictated that no single system should be grounded in more
than one place on the airplane unless specifically designed for
that kind of installation.
Bob . . .
Message 23
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| Subject: | Re: Panel vs Firewall Ground--do the electrons care? |
--> AeroElectric-List message posted by: "Roger Evenson" <revenson@comcast.net>
Thanks for that explanation. Then to be consistent, we really shouldn't use
local grounds for nav lights and landing lights.
----- Original Message -----
From: "Robert L. Nuckolls, III electrons care?" <nuckollsr@cox.net>
Subject: Re: AeroElectric-List: Panel vs Firewall Ground--do the electrons
care?
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
> <nuckollsr@cox.net> electrons care?
>
> At 06:35 PM 5/24/2005 -0700, you wrote:
>
>>--> AeroElectric-List message posted by: "Roger Evenson"
>><revenson@comcast.net>
>>
>>Just read Bob's new chapter on Audio Systems. Given that a single-point
>>ground system is best to eliminate noise from ground loops, I don't
>>understand the rationale for a separate audio ground near the radio
>>stack. Why is it considered poor practice to run both audio and all other
>>aircraft equipment grounds to a single firewall ground block?
>
> good question. Ground LOOPS are defined as two or more grounds
> for a single system or appliance. For example, fuel gages get into
> trouble when the "sender" grounds in the wing and the instrument
> grounds behind the panel. Radios or intercoms get noisy when headset
> or microphone leads ground out on the airframe while the electronics
> for the system ground elsewhere. The critical single point ground is
> for all grounds needed for each system or appliance.
>
>
>>Further, what's the difference between a single firewall ground for
>>everything and a panel ground with a wire connecting the panel ground to
>>the firewall ground? Does it matter to the audio system?
>
> One would like to minimize the numbers and lengths of wires in
> the whole aircraft . . . panels tend to have lots of grounding
> requirements for instruments, lighting, audio systems and individual
> radios. The avionics ground block offers an opportunity to
> convert your entire panel assembly into a single appliance
> by offering a local ground for all panel mounted accessories
> and extending that as a robust, high quality ground (relatively
> fat wires) to the firewall ground. You're still observing the
> necessity for making all grounds for any one system (or related
> systems like radios and audio system) at a single location and
> then extending that location down to the firewall on a few
> wires. This can have a marked effect on size of wire bundles and
> on convenience of fabrication and installation.
>
> We do this in big airplanes too . . . their are MULTIPLE single
> point grounds scattered about a biz jet . . . the designer's
> rules dictated that no single system should be grounded in more
> than one place on the airplane unless specifically designed for
> that kind of installation.
>
> Bob . . .
>
>
>
Message 24
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| Subject: | Re: Solid State Relays vs. Solenoids |
Z-USANET-MsgId: XID741JeZBkt0133X31
--> AeroElectric-List message posted by: chad-c_sip@stanfordalumni.org
> That's why I've stuck with the $LOW$ contactors in my recommendations,
> the next step up is MUCH more expensive and not likely to offer
> performance that equates to lower cost of ownership. If you had
> a Rotax alternator with only 18A of output, then some form of
> solid state contactor might be attractive for a battery master
> just to conserve on a limited energy supply . . . but a manual
> battery master is simpler yet and MORE energy efficient than
> a solid state contactor . . .
>
> Bob . . .
I'm not actually looking to replace the startrer contactors on the Lancair.
I'd need something way bigger than I linked to in my first post. Even my
master will still be a mechanical device. I'm looking to replace the
lower-current (anything under 100 amps) solenoids on the plane with
solid-state relays (A/C compressor, hydraulic pump, etc.). The concept of no
moving parts - and myself having more familiarity with solid-state relays - is
what appealed to me in replacing the coil devices. I'm not necessarily looking
to make the system less expensive. Only as reliable as with coils and maybe a
bit quieter (RFI-wise) for our stormscope antenna. If that's not going to
happen with relays I'll go back to the solenoids that are more normal.
Thanks for the input on the topic.
Chad
Chad Sipperley
Lancair IVP - turbine (under construction)
Phoenix, AZ
Message 25
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| Subject: | Re: Panel vs Firewall Ground--do the |
electrons care?
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
electrons care?
At 06:05 PM 5/25/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: "Roger Evenson"
><revenson@comcast.net>
>
>Thanks for that explanation. Then to be consistent, we really shouldn't use
>local grounds for nav lights and landing lights.
No . . . there's no risk to local grounds for devices that are not
potential victims nor antagonists. Heaters and lights fall into this
category. You're also in a low risk of problems by grounding strobe
supply locally since it's easily filtered and all potential victims
won't be looped with it.
Bob . . .
Message 26
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| Subject: | Dynon D-10A Ticking |
--> AeroElectric-List message posted by: "Jerry Isler" <jlisler@alltel.net>
Tonite I had a visitor looking at my RV-4 when he asked if he could turn
on the master switch. I said "Sure, go ahead" because I always like to see
the little lights come on and and then hear "ANGLE, ANGLE, PUSH" (Yeah
that's right, I spent the money for an AOA). Well nothing happened! No
master relay picking up, no lights, no nothing. I then tried to turn on the
Dynon thinking it would come up on battery back up. Again nothing. The
entire electrical system was dead. I immediately hooked a battery charger to
my Oddessy PC-680 and started a charge. I tried the master switch again and
everything powered up as expected so obviously the battery was completely
dead. The problem is I don't know why. I checked all of the switches and
everything was turned off so I do not think anything was left on.
So now for the real question. I have noticed lately that the Dyon D-10A
was making a ticking noise when everything on the plane was turned off. The
tick is about every second. I have the keep alive circuit wired up to an
always hot bus so that the internal battery in the Dynon will stay charged
up. I think the noise is from this circuit because I disconnected the
connector from the back of the Dynon and the noise stopped and resumed when
it was reconnected. Is this ticking noise normal? Could this be the cause of
my dead battery? Will a dead battery on the plane drain the internal battery
on the Dynon? Will a PC-680 go completely dead if you let the voltage get
down to about 10.5 volts (I have not charged the battery in a while)?
Thanks,
Jerry Isler
RV-4 N455J
Donalsonville, GA
Message 27
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| Subject: | Re: Dynon D-10A Ticking |
Z-USANET-MsgId: XID694JeZetb0438X36
--> AeroElectric-List message posted by: chad-c_sip@stanfordalumni.org
Do you have an ammeter that you could use to check the current flow out of
your battery when the Dynon is making the clicking sound? Simply disconnect
the hot (+) lead on the battery and run through your ammeter (with everything
else off!). Doing that on a Great Lakes my family recently acquired I
discovered that the slow drain that had been flattening the battery was a 9.8
mA current being eaten by the master solenoid. New solenoid, new battery, new
starter and she starts like a charm every time now (we think the starter went
bad from low-voltage starts from a drained battery over the last few years).
My understanding is that the Odyssey batteries don't mind being deep-cycled a
few times, but it might be worth disconnecting it and running a deep cycle
analysis on your charger if you've got a fancy enough one. Or you might take
it to your local Sears and see if they'll run it through their monitor for
you.
Good luck!
Chad
Chad Sipperley
Lancair IVP - turbine (under construction)
Phoenix, AZ
> --> AeroElectric-List message posted by: "Jerry Isler" <jlisler@alltel.net>
>
> Tonite I had a visitor looking at my RV-4 when he asked if he could turn
> on the master switch. I said "Sure, go ahead" because I always like to see
> the little lights come on and and then hear "ANGLE, ANGLE, PUSH" (Yeah
> that's right, I spent the money for an AOA). Well nothing happened! No
> master relay picking up, no lights, no nothing. I then tried to turn on the
> Dynon thinking it would come up on battery back up. Again nothing. The
> entire electrical system was dead. I immediately hooked a battery charger
to
> my Oddessy PC-680 and started a charge. I tried the master switch again and
> everything powered up as expected so obviously the battery was completely
> dead. The problem is I don't know why. I checked all of the switches and
> everything was turned off so I do not think anything was left on.
> So now for the real question. I have noticed lately that the Dyon D-10A
> was making a ticking noise when everything on the plane was turned off. The
> tick is about every second. I have the keep alive circuit wired up to an
> always hot bus so that the internal battery in the Dynon will stay charged
> up. I think the noise is from this circuit because I disconnected the
> connector from the back of the Dynon and the noise stopped and resumed when
> it was reconnected. Is this ticking noise normal? Could this be the cause
of
> my dead battery? Will a dead battery on the plane drain the internal
battery
> on the Dynon? Will a PC-680 go completely dead if you let the voltage get
> down to about 10.5 volts (I have not charged the battery in a while)?
>
> Thanks,
>
> Jerry Isler
> RV-4 N455J
> Donalsonville, GA
>
>
>
>
>
>
>
Message 28
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| Subject: | Re: Dynon D-10A Ticking |
Fuz1=1 Fuz2=1
--> AeroElectric-List message posted by: "Werner Schneider" <glastar@gmx.net>
Jerry,
check once your software version, there was a version which did excessive
drain the battery:
02.03 8/25/04 Added: New high-contrast skid ball for better visibility
in sunlight.
Fixed: Problem causing excessive battery drain when turned off.
current version is 2.08.
Werner
----- Original Message -----
From: "Jerry Isler" <jlisler@alltel.net>
Subject: AeroElectric-List: Dynon D-10A Ticking
> --> AeroElectric-List message posted by: "Jerry Isler"
<jlisler@alltel.net>
>
> Tonite I had a visitor looking at my RV-4 when he asked if he could turn
> on the master switch. I said "Sure, go ahead" because I always like to see
> the little lights come on and and then hear "ANGLE, ANGLE, PUSH" (Yeah
> that's right, I spent the money for an AOA). Well nothing happened! No
> master relay picking up, no lights, no nothing. I then tried to turn on
the
> Dynon thinking it would come up on battery back up. Again nothing. The
> entire electrical system was dead. I immediately hooked a battery charger
to
> my Oddessy PC-680 and started a charge. I tried the master switch again
and
> everything powered up as expected so obviously the battery was completely
> dead. The problem is I don't know why. I checked all of the switches and
> everything was turned off so I do not think anything was left on.
> So now for the real question. I have noticed lately that the Dyon D-10A
> was making a ticking noise when everything on the plane was turned off.
The
> tick is about every second. I have the keep alive circuit wired up to an
> always hot bus so that the internal battery in the Dynon will stay charged
> up. I think the noise is from this circuit because I disconnected the
> connector from the back of the Dynon and the noise stopped and resumed
when
> it was reconnected. Is this ticking noise normal? Could this be the cause
of
> my dead battery? Will a dead battery on the plane drain the internal
battery
> on the Dynon? Will a PC-680 go completely dead if you let the voltage get
> down to about 10.5 volts (I have not charged the battery in a while)?
>
> Thanks,
>
> Jerry Isler
> RV-4 N455J
> Donalsonville, GA
>
>
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