Today's Message Index:
----------------------
1. 07:14 AM - Re: Strobe switches (Robert L. Nuckolls, III)
2. 07:16 AM - Re: Strobe switches (Robert L. Nuckolls, III)
3. 08:56 AM - Re: Strobe switches (Charles Brame)
4. 11:48 AM - Re: Strobe switches (Robert L. Nuckolls, III)
5. 11:52 AM - Re: Strobe switches (Robert L. Nuckolls, III)
6. 05:39 PM - Re: Strobe switches (Bill Watson)
Message 1
INDEX | Back to Main INDEX |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Strobe switches |
At 11:27 AM 1/21/2014, you wrote:
I experienced a burned out fast-on connector at my fuse panel on the
16AWG strobe power lead between the fuse panel and the switch. My
strobe unit was a CreativAir Avi-Pak 60 watt, 4 outlet strobe power
suppy intended for experimental aircraft use. Three strobes were
connected. There was a 15amp fuse on the unit and a 15amp fuse on
the fuse panel. This was on an RV10 and there was somewhere between
10 and 20 feet of 16AWG wire in the switched power circuit.
I had difficulty identifying the burned out fast-on connector. The
circuit remained intact despite it's inability to carry the required
load. In the course of problem determination, I decided to replace
the unit. (I later determined that the unit works just fine)
Do you still have this 'problem' system?
The XPAK604X was cheaper, had more strobe pattern options and used a
control circuit which would seem to accomplish what a relay would do.
Interesting. I wonder if they 'discovered' the
features in their power demands that were so
abusive of otherwise perfectly good switches . . .
I'm gathering the hardware together to craft a
mailable data acquisition system together that
I can ship to a willing List member to gather
some definitive data on their strobe systems.
I'd like to acquire a library of data both
from systems that have suffered failures in
the power wiring . . . and some that didn't.
"When you can measure what you are speaking about,
and express it in numbers, you know something about
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."
---- Lord Kelvin ----
We've been watching these rare but significant
events for some years . . . ignorant of the
root cause. I'm thinking it's time to get some
good numbers.
Bob . . .
Message 2
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Strobe switches |
At 11:32 PM 1/20/2014, you wrote:
Bob, et.al.,
I just replaced my fourth S700-1(or equivalent) strobe switch in
about 200 hours of flying time. Both fast on terminals were badly
burned as was about an inch of the 18ga. wire attached to the fast on.
Charlie, do you want to try the solid state
relay? If you do install this relay . . .
Emacs!
. . . it will offer a plug-n-play port through which
we can gather some good numbers when the DAS system
goodies I've ordered get here . . .
Bob . . .
Message 3
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Strobe switches |
Bob,
Thanks for the response. See my answers to your questions in red below.
Charlie Brame
RV-6A N11CB
San Antonio
------------------------------------------------------------------
Time: 08:24:54 AM PST US
From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
Subject: Re: AeroElectric-List: Strobe switches
> The strobe switch is backed up by a 7 amp fuse which is
> recommended for the strobe system (Whelen) and it has never popped.
> The run of 18 ga. wire is about ten feet. Of all the switches, only
> the strobe switch gets real hot after only a few minutes of use.
Can you tell where it's getting hot?
With this latest switch failure the hot spots were the fast on
connectors at the switch, and I did not notice the switch itself getting
hot. The switch fast on tabs are externally riveted and became very
loose. There is no signs of burning of the switch itself, though
something caused the fast on tabs to become loose on the switch body.
And both of the connectors (power in and power out) were burned. In one
of the previous Carling failures, the switch was fried on the inside,
and the switch itself got hot, including the bat handle. The power
connector at the power pack is a Molex type pin plug and does not show
any heat related distress. The power supply fast on at the fuse panel
has also never shown any signs of heating. With a new switch installed,
there is no evidence of any hot spots. However, after a period of time,
the problem reoccurs.
We've had this (and similar) discussions on strobe
controls over the years. I am mystified as
to how the burning of switches and terminal
crimps seems to be concentrated on the strobe
systems . . . driven by relatively light
protection (7A fuse).
> I discovered that B&C now advertises a MilSpec
> single pole switch (MS35058-22) that is the equivalent of the
> S700-1. Would this MilSpec switch be a viable solution to the strobe
switch problem?
Your question raises some interesting points.
There seems to be something 'different' about
the strobe system current draw profile that
stresses the centers of highest-resistance
in the power path. In the past, we've seen
failures at the rivet joints on the switches,
contacts within the switches, switch rockers,
and less-than-idea crimps on terminals, etc.
Yet the RMS or average current remains so
low that a relatively fast protective device
like a fuse doesn't complain. I would REALLY
like to see the current profile on a strobe
system that has repeatedly damaged its switch.
There's got to be a characteristic unique to
strobe supplies (perhaps just this model
of supply) that's especially antagonistic
to components in the power feeder.
Getting to your specific questions. A
relay would certainly transfer the stresses
away from the switch . . . but any connecting
devices in the power path (like crimps)
would still see the 'abuse'.
It might well be that a switch with molded
terminal supports . . .
Emacs!
. . . would not offer the weaknesses of
riveted joints . . . but crimps, threaded
fasteners and internal contacts of the
switch would still be getting 'hammered'.
I do have a proof-of-concept, solid state
relay that I'd be pleased to send you. I've
like to get it into service on an often-flown
airplane and perhaps yours is the best
candidate. It appears that the strobes feeder
in your airplane would be a good location to
try the relay while potentially addressing
your specific failure mode.
I would be pleased to try your new solid state relay. However, I don't
have any test equipment and am not sure I'm smart enough to use it if I
had access. But I am open to ideas and suggestions.
Do you have access to any test equipment
that might measure and record the current
waveform impressed on the strobe switch
in your airplane?
I'm mulling over ideas for getting data
of your airplane and then perhaps expanding
the investigation to other airplanes to
see if we can identify the controlling
physics.
There are tens of thousands of airplanes
flying Carling switches in the strobe
power feed path . . . the fact that a
few folks here on the List have experienced
serial failures of these switches is
curious to say the least.
In reading some of the other responses, I'd like to clarify the
following: My system is a Whelen three light system with a single power
pack. There have been no changes or additions to the system as it was
received from the manufacturer. All bulbs and flash sequences were
factory set and the cables from the power pack to the lights are factory
supplied. The system is grounded at the power pack and the ground
appears secure. I have seen no evidence of any other over voltage, over
amperage damage to any other switches or devices. The regulator (a
generic Ford regulator) seems to work as advertised. The strobe system
is left on at all times and begins to operate when the master switch is
turned on. In other words, the switch is rarely cycled on or off.
Bob . . .
Message 4
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Strobe switches |
At 10:55 AM 1/22/2014, you wrote:
Bob,
Thanks for the response. See my answers to your questions in red below.
Charlie Brame
RV-6A N11CB
San Antonio
------------------------------------------------------------------
Time: 08:24:54 AM PST US
From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
Subject: Re: AeroElectric-List: Strobe switches
The strobe switch is backed up by a 7 amp fuse which is
recommended for the strobe system (Whelen) and it has never popped.
The run of 18 ga. wire is about ten feet. Of all the switches, only
the strobe switch gets real hot after only a few minutes of use.
Can you tell where it's getting hot?
With this latest switch failure the hot spots were the fast on
connectors at the switch, and I did not notice the switch itself
getting hot. The switch fast on tabs are externally riveted and
became very loose. There is no signs of burning of the switch itself,
though something caused the fast on tabs to become loose on the
switch body. And both of the connectors (power in and power out) were
burned. In one of the previous Carling failures, the switch was fried
on the inside, and the switch itself got hot, including the bat
handle. The power connector at the power pack is a Molex type pin
plug and does not show any heat related distress. The power supply
fast on at the fuse panel has also never shown any signs of heating.
With a new switch installed, there is no evidence of any hot spots.
However, after a period of time, the problem reoccurs.
Good data. Thanks.
I would be pleased to try your new solid state relay. However, I
don't have any test equipment and am not sure I'm smart enough to use
it if I had access. But I am open to ideas and suggestions.
Understand. Were your airplane sitting at Medicine Lodge
Intergalactic Airport, there are a number of whippy
tools on my shelf that would get us the data. I've
been considering ways to craft a DAS that could be
mailed at cheap priority mail rates and be relatively
simple to operate. I think I'm close to realizing
that goal . . . you can be the first 'victim' . . .
It will let us get data from YOUR installation,
on the ground and in just a few seconds. It's
basically a 1000 samples/second storage
'oscilloscope' that records to a hard drive.
In reading some of the other responses, I'd like to clarify the
following: My system is a Whelen three light system with a single
power pack. There have been no changes or additions to the system as
it was received from the manufacturer. All bulbs and flash sequences
were factory set and the cables from the power pack to the lights are
factory supplied. The system is grounded at the power pack and the
ground appears secure. I have seen no evidence of any other over
voltage, over amperage damage to any other switches or devices. The
regulator (a generic Ford regulator) seems to work as advertised. The
strobe system is left on at all times and begins to operate when the
master switch is turned on. In other words, the switch is rarely
cycled on or off.
Also excellent data points.
We'll move ahead as if we know what we're
doing. Some of the goodies are coming from
overseas but I can get the relay out to
you this weekend. Shoot me your mailing
address.
As soon as you and I figure that we're doing
a good thing, we'll bicycle the rig around
and get data from as many other airplanes
as we have willing participants.
Bob . . .
Message 5
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Strobe switches |
Speaking of strobe switch failures, there was
a series of exchanges here on the list a few
years back where the Lister had experienced
a rash of failures . . . which produced an
understandable bad taste in his mouth for the
Carling switches.
Is that individual still on the List or does
anyone recall who it was? I would be interesting
to know how the problem resolved.
Bob . . .
Message 6
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Strobe switches |
Yes I still have the problem system and would be happy to send to you.
Just let me know the address and it's on it's way. No return required.
Thanks
On 1/22/2014 10:10 AM, Robert L. Nuckolls, III wrote:
> <nuckolls.bob@aeroelectric.com>
>
> At 11:27 AM 1/21/2014, you wrote:
> <Mauledriver@nc.rr.com>
>
> I experienced a burned out fast-on connector at my fuse panel on the
> 16AWG strobe power lead between the fuse panel and the switch. My
> strobe unit was a CreativAir Avi-Pak 60 watt, 4 outlet strobe power
> suppy intended for experimental aircraft use. Three strobes were
> connected. There was a 15amp fuse on the unit and a 15amp fuse on the
> fuse panel. This was on an RV10 and there was somewhere between 10 and
> 20 feet of 16AWG wire in the switched power circuit.
>
> I had difficulty identifying the burned out fast-on connector. The
> circuit remained intact despite it's inability to carry the required
> load. In the course of problem determination, I decided to replace
> the unit. (I later determined that the unit works just fine)
>
> Do you still have this 'problem' system?
>
> The XPAK604X was cheaper, had more strobe pattern options and used a
> control circuit which would seem to accomplish what a relay would do.
>
> Interesting. I wonder if they 'discovered' the
> features in their power demands that were so
> abusive of otherwise perfectly good switches . . .
>
> I'm gathering the hardware together to craft a
> mailable data acquisition system together that
> I can ship to a willing List member to gather
> some definitive data on their strobe systems.
>
> I'd like to acquire a library of data both
> from systems that have suffered failures in
> the power wiring . . . and some that didn't.
>
>
> "When you can measure what you are speaking about,
> and express it in numbers, you know something about
> 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."
>
> ---- Lord Kelvin ----
>
> We've been watching these rare but significant
> events for some years . . . ignorant of the
> root cause. I'm thinking it's time to get some
> good numbers.
>
>
> Bob . . .
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
>
>
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|