Today's Message Index:
----------------------
1. 05:11 AM - Re: Re: Tips for Building a Wiring Harness (Art Zemon)
2. 05:29 AM - Re: Tips for Building a Wiring Harness (Art Zemon)
3. 05:47 AM - Re: Tips for Building a Wiring Harness (user9253)
4. 05:51 AM - Re: Re: Tips for Building a Wiring Harness (Charlie England)
5. 06:12 AM - Re: Non-aero app: 120/240 AC through 24vdc switch? (user9253)
6. 06:27 AM - Re: Re: Tips for Building a Wiring Harness (Brian Lester)
7. 06:29 AM - Shield Grounding (Art Zemon)
8. 06:29 AM - Re: Re: Non-aero app: 120/240 AC through 24vdc switch? (Robert L. Nuckolls, III)
9. 06:34 AM - Re: Shield Grounding (Robert L. Nuckolls, III)
10. 07:07 AM - Re: Shield Grounding (Art Zemon)
11. 08:32 AM - Re: Shield Grounding (Charlie England)
12. 08:36 AM - Re: Re: Non-aero app: 120/240 AC through 24vdc switch? (Eric Page)
13. 09:03 AM - Re: Shield Grounding (Robert L. Nuckolls, III)
14. 09:19 AM - Re: Re: Non-aero app: 120/240 AC through 24vdc switch? (Robert L. Nuckolls, III)
15. 09:48 AM - Re: Shield Grounding (Art Zemon)
16. 11:42 AM - Re: Non-aero app: 120/240 AC through 24vdc switch? (Eric Page)
17. 06:06 PM - Re: Silent-Hektik Regulator (user9253)
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Subject: | Re: Tips for Building a Wiring Harness |
Jon,
This is very disturbing. How much time? All of the wiring that I already
have in the plane has been labeled with Sharpies on white heat shrink. I
can still relabel a bunch of it if necessary.
-- Art Z.
On Sat, Aug 26, 2017 at 5:30 PM, jonlaury <jonlaury@impulse.net> wrote:
> Over time, I found the text made with fine pt Sharpie on white heat shrink
> fades/runs. Wish I had stayed with my original method of inkjet printed on
> white paper then cut into strips to be inserted inside clear heat shrink.
> They are crisp and legible, years later.
>
--
https://CheerfulCurmudgeon.com/
*"If I am not for myself, who is for me? And if I am only for myself, what
am I? And if not now, when?" Hillel*
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Subject: | Re: Tips for Building a Wiring Harness |
Thank you, everybody! Lots of good ideas, some I already am doing and some
are new. I had not thought of actually mounting my instrument panel on the
bench, wiring it from the back, and testing it before installing in the
plane. I will definitely do that.
Cheers,
-- Art Z.
--
https://CheerfulCurmudgeon.com/
*"If I am not for myself, who is for me? And if I am only for myself, what
am I? And if not now, when?" Hillel*
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Subject: | Re: Tips for Building a Wiring Harness |
I have not used a Sharpie to mark wires. But I have used a Sharpie to mark other
stuff and agree that it will fade over time, depending on the material and
length of time.
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=472298#472298
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Subject: | Re: Tips for Building a Wiring Harness |
Interesting result. Seems to demonstrate a principle I always try to
remember with homebuilt activities: Any variation in materials, techniques,
etc can vary outcome.
For a labeling 'variation', I've got a cheap Brother P-touch PT-530 label
printer. Configuring it for minimal label waste isn't possible, so I've
used some of the wasted material to hand-label with a black Sharpie brand
pen. To test, I left one outdoors, in the MS sun, for over a month, with no
issues.
A strange idiosyncrasy of the label material is that it sticks tenaciously
to almost any surface, but when you fold it around a wire, it doesn't want
to stick to itself. (?) After a few days, almost every label I initially
applied to wires had either dropped off, or was just barely hanging on
where the bend point touched the wire. I can't remember how I discovered
this, but if I press one half of the sticky surface on my finger (which
almost always has a bit of dust/dirt on it while working), and then re-fold
the label onto itself, it never releases again. So now, any time I'm
labeling wires, I press half the sticky surface on a finger before folding
it over a wire. Works fine; seems to last a long time.
Charlie
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On Tue, Aug 29, 2017 at 6:57 AM, Art Zemon <art@zemon.name> wrote:
> Jon,
>
> This is very disturbing. How much time? All of the wiring that I already
> have in the plane has been labeled with Sharpies on white heat shrink. I
> can still relabel a bunch of it if necessary.
>
> -- Art Z.
>
> On Sat, Aug 26, 2017 at 5:30 PM, jonlaury <jonlaury@impulse.net> wrote:
>
>> Over time, I found the text made with fine pt Sharpie on white heat
>> shrink fades/runs. Wish I had stayed with my original method of inkjet
>> printed on white paper then cut into strips to be inserted inside clear
>> heat shrink. They are crisp and legible, years later.
>>
>
>
> --
> https://CheerfulCurmudgeon.com/
>
> *"If I am not for myself, who is for me? And if I am only for myself, what
> am I? And if not now, when?" Hillel*
>
Message 5
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Subject: | Re: Non-aero app: 120/240 AC through 24vdc switch? |
What if a solid state relay and a mechanical relay are connected in parallel?
The solid state relay will turn on a fraction of a second prior to the mechanical
contacts closing and will conduct while the mechanical contacts are bouncing.
Once the mechanical contacts have stopped bouncing, then they will carry
the full load.
Or use only a solid state relay rated for the current.
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=472301#472301
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Subject: | Re: Tips for Building a Wiring Harness |
I have used clear heat shrink tube over brother labels to deal with issues
of the labels falling off or not sticking well for network cabling. Plan to
do the same in my airplane when I get to that point.
On Tue, Aug 29, 2017 at 8:58 AM Charlie England <ceengland7@gmail.com>
wrote:
> Interesting result. Seems to demonstrate a principle I always try to
> remember with homebuilt activities: Any variation in materials, techniques,
> etc can vary outcome.
>
> For a labeling 'variation', I've got a cheap Brother P-touch PT-530 label
> printer. Configuring it for minimal label waste isn't possible, so I've
> used some of the wasted material to hand-label with a black Sharpie brand
> pen. To test, I left one outdoors, in the MS sun, for over a month, with no
> issues.
>
> A strange idiosyncrasy of the label material is that it sticks tenaciously
> to almost any surface, but when you fold it around a wire, it doesn't want
> to stick to itself. (?) After a few days, almost every label I initially
> applied to wires had either dropped off, or was just barely hanging on
> where the bend point touched the wire. I can't remember how I discovered
> this, but if I press one half of the sticky surface on my finger (which
> almost always has a bit of dust/dirt on it while working), and then re-fold
> the label onto itself, it never releases again. So now, any time I'm
> labeling wires, I press half the sticky surface on a finger before folding
> it over a wire. Works fine; seems to last a long time.
>
> Charlie
>
>
> <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=icon> Virus-free.
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>
> On Tue, Aug 29, 2017 at 6:57 AM, Art Zemon <art@zemon.name> wrote:
>
>> Jon,
>>
>> This is very disturbing. How much time? All of the wiring that I already
>> have in the plane has been labeled with Sharpies on white heat shrink. I
>> can still relabel a bunch of it if necessary.
>>
>> -- Art Z.
>>
>> On Sat, Aug 26, 2017 at 5:30 PM, jonlaury <jonlaury@impulse.net> wrote:
>>
>>> Over time, I found the text made with fine pt Sharpie on white heat
>>> shrink fades/runs. Wish I had stayed with my original method of inkjet
>>> printed on white paper then cut into strips to be inserted inside clear
>>> heat shrink. They are crisp and legible, years later.
>>>
>>
>>
>>
>> --
>> https://CheerfulCurmudgeon.com/
>>
>> *"If I am not for myself, who is for me? And if I am only for myself,
>> what am I? And if not now, when?" Hillel*
>>
>
Message 7
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Subject: | Shield Grounding |
Folks,
In planning my wiring harness, the manufacturers call for shielded wires to
carry the audio signals between the audio panel and the various noise
sources. Every sample wiring diagram shows the shield tied to ground at
that manufacturer's device so, for instance, the radio manufacturer's
sample diagram shows the shield grounded at the radio and the audio panel's
sample diagram shows the same shield grounded at the audio panel.
It doesn't matter, right? Can I ground either end of the shield? I do
understand that I should not ground both ends.
Thanks,
-- Art Z.
--
https://CheerfulCurmudgeon.com/
*"If I am not for myself, who is for me? And if I am only for myself, what
am I? And if not now, when?" Hillel*
Message 8
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Subject: | Re: Non-aero app: 120/240 AC through 24vdc switch? |
At 11:14 AM 8/28/2017, you wrote:
>
>Bob,
>A thousand thanks!
>
>And I found your explorations and findings about the relay failures
>on rolll trim control boards fascinating, if for no other reason
>than the failure symptoms are almost identical to what I'm seeing
>with my product.
>
>My switch failures are beginning to occur after about 30-60 cycles.
>Thinking that the sticking was purely mechanical, and acknowledging
>the problem to users, I suggested unplugging the machine, squirting
>WD40 into the pushbutton recess and cycling the switch until they
>got a blister on their finger, to erode/smooth the imagined rough
>edges of the switch internals. It either worked or customers just
>didn't want to talk to a crazy person any more, because very few
>reported a continuing problem. I even rigged up a reciprocating saw
>with a 'boxing glove' to wear-in the switch, as a misguided,
>pre-conditioning preventative.
Yup, been there . . . or at least some of
my compadres have. There was a chronic difficulty
with nuisance tripping the ov system on the
A36/B55 series aircraft . . .that stuck its
head up several times over a span of some
30 years. One attempt at a fix included taking
brand new alternators and running them at load
on a drive stand for 20 hours or so before putting
them on the airplane . . . seems the problems were
mitigated with service time.
The operative theory at the time was that QC issues
with slip ring/brush interface was root cause of
the problem. A break-in operation seemed to help.
As it turns out, the brush/slip ring interface
was a NORMAL condition that was only a trigger
for root cause.
Got to watch that same problem pop up about every
5-10 years or so. But it wasn't until my very last
service offered to the then newly amalgamated Textron,
I suggested again, that it wasn't the alternator's
fault . . . but that of the ov regulators ov
protection system.
We started a stone simple fix before my
contract ran out. At least I didn't have to
endure the machinations and pretzel twisting
it took to get one set of guts lifted out of
a regulator with a decades long, stellar track
record and installed inside the regulator enclosure for
the Beech products. i.e. a presto-changeo
creation of a form-fit-function replacement
for a regulator that had NEVER been subjected to
DO-160 study for suitability to task. A task
that we would have accomplished in mere
days back in the day . . . took nearly a year
under the 'new order'.
>Your analysis, with remedies, is a crescendo of angelic voices,
>coincident with brilliant, golden light, illuminating the path out
>of blasphemous tinkering to electronic righteousness. I feel cleansed. :D
You're too kind . . . but you appreciate the
the kind of thought processes and experiments
that have to be conducted to (1) eliminate that
which does not work, (2) identify that which
does work and (3) sift all the options in quest of
the elegant solution.
That relay study on roll trim cards took about
two years as the activities had to be interleaved
with more pressing matters. And I was the only
one working on it. A 'tiger team' of similarly
thoughtful and motivated students of the physical
arts would have been very helpful. Same story with pitch
trim motor failures that plagued Beech to the tune
of $millions$ in warranty claims and lost
customer confidence.
Maybe I'll publish that paper one day . . . it's
a real zinger . . . and like the roll trim relay
studies, it took years of looking for the answers
to 'what if' and 'how about this'. Sorta like
technological whack-a-mole. Then one day, one
of the heads that popped up was the Eureka mole.
>One more impertinent question:
>In the zero-crossing relay suggested, the load side spec is 250vac @
>2a. The steady-state ballast load is 800ma and the motor draws about
>2a. Will the relay take it? or am I missing something here?
Good eye. Yeah, if THAT option is attractive, you'll
need a beefier device. Maybe something like this.
http://tinyurl.com/y8bfqm5o
While on a patient transfer from Wichita today I
had a brain-fart that might be the simplest
solution. You could craft your own buffer
circuit for the switch from a triac and a couple
resistors like this.
Emacs!
This could be nothing more than two resistors
soldered together with the triac, lead wires
attached and then coated in some insulating
encapsulant . . . maybe RTV, E6000 or thixotropic
epoxy. In technical terms this is known as a
"Kludge".
This would reduce stresses on your switch to mere
tens of milliamps and then only for tens of
microseconds at each re-triggering event just
after the ac wave form zero-crossing. Even if the
switch were close at the top of the wave form,
current through the switch and its series resistor
would be limited to an amp or so and again, for
tens of microseconds.
This buffer for your switch contacts raises
potential for a new failure mode. . . corrosion
over time on switch contacts causing them
to STOP conducting . . . not enough 'cleansing
current' flowing during each switch closure
to keep them free of oxides. But that risk
is generally years out into the future.
Bob . . .
Message 9
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Subject: | Re: Shield Grounding |
At 08:27 AM 8/29/2017, you wrote:
>Folks,
>
>In planning my wiring harness, the manufacturers call for shielded
>wires to carry the audio signals between the audio panel and the
>various noise sources. Every sample wiring diagram shows the shield
>tied to ground at that manufacturer's device so, for instance, the
>radio manufacturer's sample diagram shows the shield grounded at the
>radio and the audio panel's sample diagram shows the same shield
>grounded at the audio panel.
>
>It doesn't matter, right? Can I ground either end of the shield? I
>do understand that I should not ground both ends.
Follow the manufacturer's instructions. Grounding
shields at both ends is never 'better' from the
standpoint of breaking the electro-static, noise
coupling mode . . . and sometimes grounding at
both ends can pose new problems.
Bob . . .
Message 10
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Subject: | Re: Shield Grounding |
On Tue, Aug 29, 2017 at 8:33 AM, Robert L. Nuckolls, III <
nuckolls.bob@aeroelectric.com> wrote:
> At 08:27 AM 8/29/2017, you wrote:
>
> Folks,
>
> In planning my wiring harness, the manufacturers call for shielded wires
> to carry the audio signals between the audio panel and the various noise
> sources. Every sample wiring diagram shows the shield tied to ground at
> that manufacturer's device so, for instance, the radio manufacturer's
> sample diagram shows the shield grounded at the radio and the audio panel's
> sample diagram shows the same shield grounded at the audio panel.
>
> It doesn't matter, right? Can I ground either end of the shield? I do
> understand that I should not ground both ends.
>
>
> Follow the manufacturer's instructions. Grounding
> shields at both ends is never 'better' from the
> standpoint of breaking the electro-static, noise
> coupling mode . . . and sometimes grounding at
> both ends can pose new problems.
>
>
Bob,
I am confused because the manufacturers have given conflicting info. The
audio panel shows all shields grounded at the audio panel (and open at the
radios). The radios show the shields grounded at the radios (and open at
the audio panel). As far as I can tell, it should not matter. I should be
able to ground either end of the shield for any particular wire (and leave
the other end open). Right?
-- Art Z.
--
https://CheerfulCurmudgeon.com/
*"If I am not for myself, who is for me? And if I am only for myself, what
am I? And if not now, when?" Hillel*
Message 11
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Subject: | Re: Shield Grounding |
On 8/29/2017 9:05 AM, Art Zemon wrote:
>
>
> On Tue, Aug 29, 2017 at 8:33 AM, Robert L. Nuckolls, III
> <nuckolls.bob@aeroelectric.com <mailto:nuckolls.bob@aeroelectric.com>>
> wrote:
>
> At 08:27 AM 8/29/2017, you wrote:
>> Folks,
>>
>> In planning my wiring harness, the manufacturers call for
>> shielded wires to carry the audio signals between the audio panel
>> and the various noise sources. Every sample wiring diagram shows
>> the shield tied to ground at that manufacturer's device so, for
>> instance, the radio manufacturer's sample diagram shows the
>> shield grounded at the radio and the audio panel's sample diagram
>> shows the same shield grounded at the audio panel.
>>
>> It doesn't matter, right? Can I ground either end of the shield?
>> I do understand that I should not ground both ends.
>
> Follow the manufacturer's instructions. Grounding
> shields at both ends is never 'better' from the
> standpoint of breaking the electro-static, noise
> coupling mode . . . and sometimes grounding at
> both ends can pose new problems.
>
> Bob,
>
> I am confused because the manufacturers have given conflicting info.
> The audio panel shows all shields grounded at the audio panel (and
> open at the radios). The radios show the shields grounded at the
> radios (and open at the audio panel). As far as I can tell, it should
> not matter. I should be able to ground either end of the shield for
> any particular wire (and leave the other end open). Right?
>
> -- Art Z.
>
>
> --
> https://CheerfulCurmudgeon.com/
>
> /"If I am not for myself, who is for me? And if I am only for myself,
> what am I? And if not now, when?" Hillel/
Art,
The reason for such confusion with shields is that with most (not all)
*data* transmission, the shield is purely a shield and doesn't
participate in electron flow (to complete the circuit). But with audio,
the shield is often called on to do 'double duty'; providing a shield
*and* providing the return path for the electron flow. When that's the
case, you must connect the shield at both ends. A quick way to tell is
that if you see an audio 'hi', an audio 'lo', *and* a shield (3 lines on
the drawing), the shield can be connected at one end. But if you only
see an audio 'hi' and a shield, the shield is acting as both the 'lo'
and the shield.
An example would be the headphone wire in many mono intercoms. You'll
typically see the headphone 'hi' and a shield wire on the drawing. Since
almost all intercoms spec that the mic & headphone jacks be isolated
from the airframe (ground), if you don't connect the shield at both ends
(intercom & jack), you won't have a complete circuit and the headphones
won't work.
Charlie
---
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Message 12
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Subject: | Re: Non-aero app: 120/240 AC through 24vdc switch? |
>
>> In the zero-crossing relay suggested, the load side spec is 250vac @ 2a. T
he steady-state ballast load is 800ma and the motor draws about 2a. Will the
relay take it? or am I missing something here?
> On Aug 29, 2017, at 6:29 AM, Robert L. Nuckolls, III <nuckolls.bob@aeroele
ctric.com> wrote:
> Good eye. Yeah, if THAT option is attractive, you'll need a beefier device
. Maybe something like this.
>
> http://tinyurl.com/y8bfqm5o
Careful... the linked SSR is a DC-DC device. It's basically an opto-isolat
ed MOSFET or Darlington. It might work as a rectifier, but only briefly!
For this application the output side has got to be labeled for AC, then it'l
l contain a triac or souce-connected N-MOSFETs.
If John isn't hesitant to use offshore sources for his parts, he might try t
hese...
http://www.ebay.com/itm/112021093981
I've used a couple in mains-powered projects and had no trouble with them. T
hey're not a brand anyone has ever heard of, but they seem to work, the pric
e is right, and the screw terminals lend themselves to a field retrofit bett
er than a PCB-mounted SIP package.
If heat sinking or a safety cover are desired, see...
http://www.ebay.com/itm/112159075071
and...
http://www.ebay.com/itm/112266161948
Keep in mind also that anything from China with a $0.99 price tag and a name
brand like OMRON printed on it is going to be a case of blatant IP theft.
Eric
Message 13
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Subject: | Re: Shield Grounding |
>
>=C2
>Bob,
>
>I am confused because the manufacturers have
>given conflicting info. The audio panel shows
>all shields grounded at the audio panel (and
>open at the radios). The radios show the shields
>grounded at the radios (and open at the audio
>panel). As far as I can tell, it should not
>matter. I should be able to ground either end of
>the shield for any particular wire (and leave the other end open). Right?
Correct . . . it never matters at which end it
is grounded . . . but unless the shield is
doubling both ELECTRO-STATIC NOISE COUPLING
combined with a SIGNAL -or- POWER PATH, then
grounding at either end is sufficient and
correct.
If the shield is intended to serve a dual
purpose, then the installation instructions
will be specific as to how BOTH ends of
the shield are managed.
Example: I used to supply an LED annunciator
fixture where is was MECHANICALLY convenient
to use a single shielded wire to make connections
with the back of the LED.
Emacs!
In this case, the shielding was NOT being
utilized as a noise mitigation feature . . . it
was simply one of the power pathways for the
lamp.
In this case, installation instructions
called out the appropriate treatment . . .
Emacs!
We have often pondered design features called
out in various documents over the years here
on the list . . . lamenting the fact that we
could not ask the designer to explain the
simple-ideas in physics and/or mechanics that
drove the design.
The simplest thing to do is follow the instructions.
On occasion we have discovered errors in
reasoning/implementation of design goals but
this is very rare.
Bob . . .
Message 14
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Subject: | Re: Non-aero app: 120/240 AC through 24vdc |
switch?
>On Aug 29, 2017, at 6:29 AM, Robert L. Nuckolls, III
><<mailto:nuckolls.bob@aeroelectric.com>nuckolls.bob@aeroelectric.com> wrote:
>>Good eye. Yeah, if THAT option is attractive, you'll need a beefier
>>device. Maybe something like this.
>>
>>http://tinyurl.com/y8bfqm5o
>
>
>Careful... the linked SSR is a DC-DC device. It's basically an
>opto-isolated MOSFET or Darlington. It might work as a rectifier,
>but only briefly!
>
>For this application the output side has got to be labeled for AC,
>then it'll contain a triac or souce-connected N-MOSFETs.
>
>If John isn't hesitant to use offshore sources for his parts, he
>might try these...
>
><http://www.ebay.com/itm/112021093981>http://www.ebay.com/itm/112021093981
>
>I've used a couple in mains-powered projects and had no trouble with
>them. They're not a brand anyone has ever heard of, but they seem
>to work, the price is right, and the screw terminals lend themselves
>to a field retrofit better than a PCB-mounted SIP package.
Good catch! Thanks.
Bob . . .
Message 15
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Subject: | Re: Shield Grounding |
Thank you for the clarification.
-- Art Z.
Sent from my phone. Please excuse brevity and bizarre typos.
On Aug 29, 2017 11:43 AM, "Robert L. Nuckolls, III" <
nuckolls.bob@aeroelectric.com> wrote:
>
> =C3=82
> Bob,
>
> I am confused because the manufacturers have given conflicting info. The
> audio panel shows all shields grounded at the audio panel (and open at th
e
> radios). The radios show the shields grounded at the radios (and open at
> the audio panel). As far as I can tell, it should not matter. I should be
> able to ground either end of the shield for any particular wire (and leav
e
> the other end open). Right?
>
>
> Correct . . . it never matters at which end it
> is grounded . . . but unless the shield is
> doubling both ELECTRO-STATIC NOISE COUPLING
> combined with a SIGNAL -or- POWER PATH, then
> grounding at either end is sufficient and
> correct.
>
> If the shield is intended to serve a dual
> purpose, then the installation instructions
> will be specific as to how BOTH ends of
> the shield are managed.
>
> Example: I used to supply an LED annunciator
> fixture where is was MECHANICALLY convenient
> to use a single shielded wire to make connections
> with the back of the LED.
>
> [image: Emacs!]
>
>
> In this case, the shielding was NOT being
> utilized as a noise mitigation feature . . . it
> was simply one of the power pathways for the
> lamp.
>
> In this case, installation instructions
> called out the appropriate treatment . . .
>
> [image: Emacs!]
>
> We have often pondered design features called
> out in various documents over the years here
> on the list . . . lamenting the fact that we
> could not ask the designer to explain the
> simple-ideas in physics and/or mechanics that
> drove the design.
>
> The simplest thing to do is follow the instructions.
> On occasion we have discovered errors in
> reasoning/implementation of design goals but
> this is very rare.
>
>
> Bob . . .
>
Message 16
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Subject: | Re: Non-aero app: 120/240 AC through 24vdc switch? |
Upon reflection, the SSR that I linked to won't work without some redesign of the
machine's circuitry, as it needs a DC input. The easiest retrofit for Jon
to do would be to use an AC-AC SSR and control it with the existing switch that's
already in the machine.
Here's an eBay search for parts that will work: http://preview.tinyurl.com/ybqcog6g
These SSRs are available from 10A to 100A; just change the eBay search term.
If using a known-source part is an issue, here's a Digi-Key search for AC-AC zero-cross SSRs, 5A or greater, sorted by price: http://preview.tinyurl.com/yamzd5vc
Connect as shown in the attached diagram.
Eric
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=472323#472323
Attachments:
http://forums.matronics.com//files/ssr_ckt_436.jpg
Message 17
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Subject: | Re: Silent-Hektik Regulator |
Dan Horton conducted an experiment similar to mine above except that he shut off
the avionics first. His alternator is a Plane Power 60A. With the battery
disconnected from the aircraft electrical system, the voltage varied between 13
and 16 volts (as far as he could tell without data logging instruments). So
it appears that 3-phase common alternators require a battery to stabilize voltage
just like permanent-magnet single-phase alternators do.
You can read his post here:
http://www.vansairforce.com/community/showthread.php?p=1200109#post1200109
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=472337#472337
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