Today's Message Index:
----------------------
1. 06:41 AM - Re: Work bench cord clutter solution (racerjerry)
2. 07:46 AM - Re: 24x7diy LED noise experiment (update) (Robert L. Nuckolls, III)
3. 08:25 AM - Re: WigWag's resistors for HID circuit (Robert L. Nuckolls, III)
4. 08:31 AM - Re: Re: Work bench cord clutter solution (Robert L. Nuckolls, III)
5. 08:46 AM - Re: Re: Work bench cord clutter solution (Robert L. Nuckolls, III)
6. 09:17 AM - Re: contactor not contacting! (Roger & Jean Curtis)
7. 09:41 AM - Re: 24x7diy LED noise experiment (update) (Holger Selover-Stephan)
8. 10:05 AM - Re: Re: Work bench cord clutter solution (rayj)
9. 10:08 AM - Re: contactor not contacting! (Robert L. Nuckolls, III)
10. 10:27 AM - Re: 24x7diy LED noise experiment (update) (Robert L. Nuckolls, III)
11. 11:09 AM - Re: WigWag's resistors for HID circuit (B Tomm)
12. 03:21 PM - Re: Cross feed contactor current (Dan Charrois)
13. 09:26 PM - Re: 24x7diy LED noise experiment (update) (Holger Selover-Stephan)
14. 11:23 PM - Re: WigWag's resistors for HID circuit (B Tomm)
15. 11:52 PM - Help need for Wrapping Machine with Built-In Scale (Maathai Wangari)
Message 1
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Subject: | Re: Work bench cord clutter solution |
ALTERNATIVE - If you live near a Micro Center store, they sell a nice $22 all-metal
black 12 outlet 3 foot long power strip that is also ideal for workbench
mounting. This device offers no surge protection; however, I merely power this
strip from a high energy surge protector (on floor) for full protection. SKU
number is 338525; mfg p/n is 576041. If you dont live near a Micro Center store,
their shipping seems reasonable; for me in NY, shipping would be $6.
--------
Jerry King
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=396082#396082
Message 2
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Subject: | Re: 24x7diy LED noise experiment (update) |
At 10:38 PM 3/11/2013, you wrote:
Hi Bob, all,
Do you have an update on this project? I tried to follow the thread
back to the start, but couldn't quite. Are you testing with these lights:
http://24x7diy.com/product_info.php/products_id/94
Are they emitting RF noise? A friend of mine installed lights similar to these:
http://www.ebay.com/itm/170941144735?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649
He reports no discernible RF noise.
I was considering a pair of these for installation into the cowling:
Adapting commercial-off-the-shelf (COTS)
products into alternative environments comes
with some risks. Fortunately risks are very
low for the LED lighting experiments. One
first looks for a source of adequate light
output. After finding a suitable candidate,
is it easily mounted to the aircraft? Finally,
does it produce noise that exceeds limits for
your design goals?
For some builders, no amount of noise is a
big deal, no so for others.
The 23x7diy products are nicely packaged,
they DO produce a non-quantified level of
noise that the builder believed was problematic
and there's a nice recess at the rear of the
housing conducive to a well considered
installation of a filter. The last of the
materials I need came in the mail yesterday
so I'll proceed with the filter project for
these lamps.
The fixture you cited will have to go through
the same processes. First see if the light
output is adequate to your needs. I used to
shine a 6v fisherman's lantern around the
attendees of my seminars while asking them
to consider if the light output was sufficient
for night landings. I suggested that I'd
be willing to duct-tape it to my J-3's
struts and demonstrate adequacy to the task.
That was a 3-watt landing light!!! Bottom
line is that it takes very little total
light to assist you in conducting greasers on
the otherwise dark terra firma.
Then see if the noise (there is ALWAYS
emitted noise) is too much for your
situation, If too much, then you go after
it as a separate but final issue.
Bob . . .
Bob . . .
Message 3
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Subject: | Re: WigWag's resistors for HID circuit |
At 12:29 AM 3/12/2013, you wrote:
Bob,
I have two 55watt HID for landing lights. I bought the following flasher
which failed after a few minutes of run time. See,
http://sos-production.s3.amazonaws.com/docs/ETHFSS-SP.pdf
I then ordered the heavy duty version, but had the same result. See,
http://sos-production.s3.amazonaws.com/images/ETHDSS-SP%20Fold%20A.pdf
I now see B and C sells one (which I plan to order) and notice that the
wiring diagram (when using LED or HID) has a couple 75 ohm resistors added
to the circuit. I don't know what these are for but wonder if they are to
protect the solid state flasher. If so, perhaps I should have used
something similar with my first product? Can you describe the function of
the resistors?
Are these truly (H)ight(I)intensity(D)ischarge lamps?
In other words, do they come with ballasts to convert
the 14v DC to high voltages necessary for their
ignition and operation? If so, have they been characterized
for performance in a wig-wag system? ALL HID lamps have
a 'warm up' period of 30 seconds to a minute after
first power wherein their light output increases and
stabilizes. They probably should not be flashed
during this period of time. After that, it seems that
flashing is tolerated well and their operating temperatures
stay adequately warm with a 50% duty cycle of operation.
If your 'lamps' were killing solid state flashers
I suspect inductive reaction from the ballasts
produced spikes that exceed voltage ratings on the
flasher's output transistors. It's unlikely that
the transistors failed due to an over current
situation. The fact that they ran for several
minutes suggests a "pecking away" at the transistors
with a succession of events.
A relay flasher like the B&C product would not
be vulnerable to this kind of failure. The resistors
were added to accommodate the flasher's original
design goals to service incandescent lamps.
The flasher would not function with LED lamps.
HID lamps are a third and entirely different
issue. You probably WILL need the resistors.
Solid state flashing would be preferred but
you'd want to identify root cause for the failures
and fix it. The open source flasher we did
for leds is fitted with spike suppression
on the output transistors. This product might
do the job for you. I could send you one to
try out. But in any case, I would always operated
the lamps at Full-ON for about a minute before
reverting to the wig-wag mode.
It occurs to me that we could do a HID version
of this flasher that automatically forces a
one-minute warm up period before allowing wig-wag
operations to commence. I'd have to consult my
software guru on that. In the mean time, you
could conduct the experiment to see if my design
goals for the LED/Incandescent technologies
are sufficiently robust to handle your HID
fixtures. If you want to try the relay-flasher
from B&C, DO add the resistors.
Actually, I have a couple of HID conversion
kits that I tried on my Kia last year and
reverted back to incandescent. I'll drag
those out and see how they behave on my bench
first.
Bob . . .
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Subject: | Re: Work bench cord clutter solution |
At 08:39 AM 3/12/2013, you wrote:
>
>ALTERNATIVE - If you live near a Micro Center
>store, they sell a nice $22 all-metal black 12
>outlet 3 foot long power strip that is also
>ideal for workbench mounting. This device
>offers no surge protection; however, I merely
>power this strip from a high energy surge
>protector (on floor) for full protection. SKU
>number is 338525; mfg p/n is 576041. If you
>dont live near a Micro Center store, their
>shipping seems reasonable; for me in NY, shipping would be $6.
>
>--------
>Jerry King
Cool! I have an all-metal long plug strip
on one bench that I bought at Big-Lots a
couple of years ago for $20. VERY nice find
but they never came back to the store.
I'll explore your source. Incidentally, that
business about 'surge protection' is mostly
smoke and mirrors. I'm aware of no products
that benefit from such external protections.
I've never seen an owner's manual that suggests
the customer operate their new acquisition through
a surge protected outlet. All modern electronics
are fitted with some level of incoming surge
protection as a matter of good design practice.
That's what keeps the MOVs and Transorbs flowing
off the production lines by the millions . . .
not for external but internal protection of
vulnerable components. Adding it to a plug-strip
is like hanging a fox tail on your car's antenna
'cause it makes it look like you're going fast.
Bob . . .
Message 5
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Subject: | Re: Work bench cord clutter solution |
At 08:39 AM 3/12/2013, you wrote:
>
>ALTERNATIVE - If you live near a Micro Center store, they sell a
>nice $22 all-metal black 12 outlet 3 foot long power strip that is
>also ideal for workbench mounting.
I ordered one. On-the-doorstep-price after
adding shipping and taxes (10%) it came to
$30.50. About the same price as the eBay
offer but with 12 outlets instead of 9.
Better deal.
Bob . . .
Message 6
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Subject: | contactor not contacting! |
Based on the facts (1) you can hear it operate
whether it connects or not and (2) once connected
it stays connected is a strong indicator of a
bad contactor. I believe all the Pawnee Plant
aircraft went 28v in '78 so your airplane probably
has the legacy 12v PMB/Stancore/White-Rogers contactor.
Does it look like this?
WHITE RODGERS70-902
<http://www.newark.com/productimages/nio/standard/4298109.jpg>
If so, you could get a 'test' replacement from
Newark for about $25. (Cat# 35M2084 which is a
4-terminal device. You'll have to add your own
jumper between coil-hot and BAT terminal)If
that 'cures' the problem, you can go for the
holy-watered part.
If it's some other part, post a picture of
it and we can probably identify it's generic
roots.
I'd like to have your failed part to do a tear
down inspection and report to be posted her
on the List and archived on the website.
Bob,
Thanks for the reply. I have a 3 terminal continuous
duty 12V contactor that I will put in as soon as the
weather cooperates for some outdoor maintenance.
Will mail the junk contactor to you as soon as it is liberated.
Roger
_____
<http://www.spamfighter.com/len>
.
Do you have a slow PC?
<http://www.spamfighter.com/SLOW-PCfighter?cid=sigen>
Try a free scan!
Message 7
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Subject: | Re: 24x7diy LED noise experiment (update) |
On Mar 12, 2013, at 7:44 AM, Robert L. Nuckolls, III wrote:
> The last of the
> materials I need came in the mail yesterday
> so I'll proceed with the filter project for
> these lamps.
Thank you for your response, and update on your noise filter project. I'll wait
to hear from your further findings. No noise would allow leaving the lights on
for collision protection.
Also, I'm interested in as much light as I can get for an emergency off-field landing
and when taxiing around in the dark.
Thanks!
Holger
Message 8
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Subject: | Re: Work bench cord clutter solution |
My experience with surge protectors on telephone lines has been that the
external ones I have used have sacrificed themselves and other items
have not been damaged. The events took place during electrical storms.
I've never had a similar experience with any 110/220 protectors. Did
have a fuse blow in our transformer out front, but that's a different
discussion all together.
Raymond Julian
Kettle River, MN.
"And you know that I could have me a million more friends,
and all I'd have to lose is my point of view." - John Prine
On 03/12/2013 10:30 AM, Robert L. Nuckolls, III wrote:
> <nuckolls.bob@aeroelectric.com>
>
> At 08:39 AM 3/12/2013, you wrote:
>> <gki@suffolk.lib.ny.us>
>>
>> ALTERNATIVE - If you live near a Micro Center store, they sell a nice
>> $22 all-metal black 12 outlet 3 foot long power strip that is also
>> ideal for workbench mounting. This device offers no surge
>> protection; however, I merely power this strip from a high energy
>> surge protector (on floor) for full protection. SKU number is
>> 338525; mfg p/n is 576041. If you donEUR^(TM)t live near a Micro
>> Center store, their shipping seems reasonable; for me in NY, shipping
>> would be $6.
>>
>> --------
>> Jerry King
>
> Cool! I have an all-metal long plug strip
> on one bench that I bought at Big-Lots a
> couple of years ago for $20. VERY nice find
> but they never came back to the store.
>
> I'll explore your source. Incidentally, that
> business about 'surge protection' is mostly
> smoke and mirrors. I'm aware of no products
> that benefit from such external protections.
>
> I've never seen an owner's manual that suggests
> the customer operate their new acquisition through
> a surge protected outlet. All modern electronics
> are fitted with some level of incoming surge
> protection as a matter of good design practice.
>
> That's what keeps the MOVs and Transorbs flowing
> off the production lines by the millions . . .
> not for external but internal protection of
> vulnerable components. Adding it to a plug-strip
> is like hanging a fox tail on your car's antenna
> 'cause it makes it look like you're going fast.
>
>
> Bob . . .
>
>
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Subject: | contactor not contacting! |
>
>
>Bob,
>
>
>Thanks for the reply. I have a 3 terminal continuous
>
>duty 12V contactor that I will put in as soon as the
>
>weather cooperates for some outdoor maintenance.
>
>
>Will mail the junk contactor to you as soon as it is liberated.
>
>
Great! I'll tear down, photograph, analyse and share . . .
Bob . . .
Message 10
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Subject: | Re: 24x7diy LED noise experiment (update) |
At 11:40 AM 3/12/2013, you wrote:
><holger-d@shadowbrush.com>
>
>On Mar 12, 2013, at 7:44 AM, Robert L. Nuckolls, III wrote:
> > The last of the
> > materials I need came in the mail yesterday
> > so I'll proceed with the filter project for
> > these lamps.
>
>Thank you for your response, and update on your noise filter
>project. I'll wait to hear from your further findings. No noise
>would allow leaving the lights on for collision protection.
Keep in mind that my work here is on one product
based on non-quantified perceptions of noise.
The owner of these lights complained about it,
I could detect it here and have a plan for
attenuating it . . . but just how much noise
is created compared to contemporary limits for
qualification onto a type certificated aircraft
cannot be known without going to the lab.
The fact that this particular product produced
detectable noise is not a guarantee that (1)
contemporary qualification limits will be achieve
with my experiments nor (2) does it guarantee
that user perceptions of noise will be driven
below acceptable limits.
Filters are NEVER 100.000% effective.
They are attenuators tailored to reduce noise
to acceptable levels which is never zero. For
example, here's a plot of the noise from a blower
motor that was tearing up the ADF on a King Air
after I crafted a filter for it.
All I had to do was get the noise below the limit line
. . . in this case the filter was exceedingly effective.
But had my efforts produced a plot that was still
trashy out to 30MHz, all I have to do is get
below the limit line.
[]
Until we do similar investigations for our experiments,
the best we can expect is: "This experiment reduced noise
to the point where the customer doesn't care about what's
left over." It may still fail miserably in the DO-160
lab. Just because the original observer is satisfied with
the outcome does not mean all future observers will share
the perception.
>Also, I'm interested in as much light as I can get for an emergency
>off-field landing and when taxiing around in the dark.
Okay, your design goals call for LOTS of light
but in situations that may amount to 0.0001%
and 1.0% of total operations respectively.
These may be situations wherein noise is the
last of your worries.
Bob . . .
Message 11
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Subject: | WigWag's resistors for HID circuit |
Thanks for the thoughtful response.
Yes my "lamps" are true HID in that they have the ballasts.
I have measured the current draw (to the ballast) after the first flasher
failed. On a digital multimeter they start at about 7 amp as I recall and
settle down at around 5 amp. There may be a spike that my meter doesn't
show. The flasher paper work says it is good for 9amp (14 amp for the heavy
duty). I have failed one of each now.
My procedure was to turn on the lamps in steady state first and then switch
to flashing mode after they were very bright (hot). This was about 10-15
seconds or so but definitely not a minute. This was going to be my operating
procedure. Land and take off with full steady lights. Flash for enroute
cruising.
According to the manufacture of the flashers, they are not
designed/recommended for HID although the paperwork doesn't specifically say
not to use with HID. Some on VAF use the this flasher with 35 watt HID with
no reported problems that I have seen.
The flashers have multiple flash patterns. Most way too quick for the HID.
I was only using the slow wigwag version. 1.9 flashes per second as I
recall. The flasher/HID combination did work well in producing a nice flash
while it lasted.
I like the HID (very bright and lower current draw), and I think flashing is
a great anti-collision feature. I'm really wanting a flasher that can take
the "abuse" if that is what is causing the failures. This is why I'm
interested in the B and C flasher. But when I read the spec, it says it's a
solid state flasher. This make me think it may fail in the same way as the
others. The resistors were the difference.
I'm willing to try whatever you recommend.
Bevan
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Tuesday, March 12, 2013 8:23 AM
Subject: Re: AeroElectric-List: WigWag's resistors for HID circuit
--> <nuckolls.bob@aeroelectric.com>
At 12:29 AM 3/12/2013, you wrote:
Bob,
I have two 55watt HID for landing lights. I bought the following flasher
which failed after a few minutes of run time. See,
http://sos-production.s3.amazonaws.com/docs/ETHFSS-SP.pdf
I then ordered the heavy duty version, but had the same result. See,
http://sos-production.s3.amazonaws.com/images/ETHDSS-SP%20Fold%20A.pdf
I now see B and C sells one (which I plan to order) and notice that the
wiring diagram (when using LED or HID) has a couple 75 ohm resistors added
to the circuit. I don't know what these are for but wonder if they are to
protect the solid state flasher. If so, perhaps I should have used
something similar with my first product? Can you describe the function of
the resistors?
Are these truly (H)ight(I)intensity(D)ischarge lamps?
In other words, do they come with ballasts to convert the 14v DC to high
voltages necessary for their ignition and operation? If so, have they been
characterized for performance in a wig-wag system? ALL HID lamps have a
'warm up' period of 30 seconds to a minute after first power wherein their
light output increases and stabilizes. They probably should not be flashed
during this period of time. After that, it seems that flashing is tolerated
well and their operating temperatures stay adequately warm with a 50% duty
cycle of operation.
If your 'lamps' were killing solid state flashers I suspect inductive
reaction from the ballasts produced spikes that exceed voltage ratings on
the flasher's output transistors. It's unlikely that the transistors failed
due to an over current situation. The fact that they ran for several minutes
suggests a "pecking away" at the transistors with a succession of events.
A relay flasher like the B&C product would not be vulnerable to this kind of
failure. The resistors were added to accommodate the flasher's original
design goals to service incandescent lamps.
The flasher would not function with LED lamps.
HID lamps are a third and entirely different issue. You probably WILL need
the resistors.
Solid state flashing would be preferred but you'd want to identify root
cause for the failures and fix it. The open source flasher we did for leds
is fitted with spike suppression on the output transistors. This product
might do the job for you. I could send you one to try out. But in any case,
I would always operated the lamps at Full-ON for about a minute before
reverting to the wig-wag mode.
It occurs to me that we could do a HID version of this flasher that
automatically forces a one-minute warm up period before allowing wig-wag
operations to commence. I'd have to consult my software guru on that. In the
mean time, you could conduct the experiment to see if my design goals for
the LED/Incandescent technologies are sufficiently robust to handle your HID
fixtures. If you want to try the relay-flasher from B&C, DO add the
resistors.
Actually, I have a couple of HID conversion kits that I tried on my Kia last
year and reverted back to incandescent. I'll drag those out and see how they
behave on my bench first.
Bob . . .
Message 12
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Subject: | Re: Cross feed contactor current |
Hi Bob, and everyone who respond - thanks for doing so!
It's good to see that the charge differential between two batteries isn't enough
to generate considerable current when they're connected in parallel. I suspected
it might be so, considering how many wiring diagrams I've seen with a cross-feed
contactor or equivalently, two battery contactors to the same bus, but
it's nice to be able to verify the current response curve (40A peak trailing
off quickly) from the experiment you did. It's always good to be able to back
up assumptions with real information.
> Have you conducted an energy study on your
> anticipated operational needs? Certainly
> a panel full of electro-whizzies drives notions
> of extra-ordinary electrical system demands
> but have you worked out the numbers?
The reason I was considering Z-14 instead of Z-13/8 was for a few reasons:
- I did do a load analysis, but as it was planned, my endurance bus had the potential
to be drawing around 10A. I may be able to get that down a bit - I had
been assuming "worst case scenario" of intermittent loads being always on, which
of course isn't true... and I may have to make more critical decisions on
what really is essential vs. just nice to have. I just want to make sure I won't
overtaxing an 8 amp backup alternator enroute during a possible diversion
due to electrical problems of the primary alternator... Maybe Z-12 might be preferable
to Z-14 if the 8 amp isn't enough?
- I've heard people sometimes having difficulty starting an IO-540 in cold weather
with a PC680. The battery is aft of the baggage compartment, so there are
some losses due to the length of the wire run, which don't help matters either.
Some put a larger PC925 back there, but I'm already expecting a fairly aft
CG as it is, adding oxygen back there as well. So placing a PC680 in the firewall
seems like an obvious choice to bring the CG forward, having a much shorter
wire run to the starter, and allowing me to connect the two with the cross-feed
contactor for more power in starting if needed.
- I've also heard of EFISes rebooting during engine start due to the voltage sagging.
Since I'm displaying engine information on the EFISes, that doesn't sound
like such a good situation. One possibility is to provide backup power to
them with something like the TCW Integrated Backup battery (one of the options
my EFIS manufacturer, Advanced Flight Systems, recommends). But it did strike
me that a more efficient approach might be to use a separate PC680 battery
for that purpose, if there was the use for one for other reasons anyway. Of course,
that wouldn't work in situations where I have to cross-tie the two batteries
for starting, but at least it would help where I didn't. I was planning
on making a slight change to Z-14 so the cross-feed isn't closed necessarily
automatically for starting.
- I'm still trying to decide on an ignition system. I'd like the idea of dual
E-mag "P" models (sometimes called P-mags) if they have their 6 cylinder versions
available soon. Failing that, I'm still leaning towards electronic ignition
of some kind, but if I go that route, I'd like a completely redundant electrical
system for each ignition source. For that, Z-14 seems the best choice.
Nonetheless, I'll continue to see if I can tweak things so that something like
Z-13/8 will work - I agree it's a simplified, lighter, and less expensive design
than Z-14, and may even provide better reliability for some types of failures.
Thanks for sending the link to the sample load planning Excel files as well
- I'm going through them to see if my numbers are obviously out of whack, and
to get ideas to see if there is anything I may have missed.
Dan
--
Syzygy Research & Technology
Box 83, Legal, AB T0G 1L0 Canada
Phone: 780-961-2213
Message 13
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Subject: | Re: 24x7diy LED noise experiment (update) |
On Mar 12, 2013, at 10:26 AM, Robert L. Nuckolls, III wrote:
> Keep in mind that my work here is on one product
> based on non-quantified perceptions of noise.
> The owner of these lights complained about it,
> I could detect it here and have a plan for
> attenuating it . . . but just how much noise
> is created compared to contemporary limits for
> qualification onto a type certificated aircraft
> cannot be known without going to the lab.
I think my expectations, or I should rather say: hopes, are in line with this.
My aircraft is not type certified, and if there's a little noise during short-timed
operation, I'll take that over paying several hundred dollars for one of
the aviation lights, which might not fare all that much better even.
> The fact that this particular product produced
> detectable noise is not a guarantee that (1)
> contemporary qualification limits will be achieve
> with my experiments nor (2) does it guarantee
> that user perceptions of noise will be driven
> below acceptable limits.
>
> Filters are NEVER 100.000% effective.
> They are attenuators tailored to reduce noise
> to acceptable levels which is never zero.
Interesting what you say. And I think I follow, aided by a background in science
in my gray past, alas in a different field.
> Until we do similar investigations for our experiments,
> the best we can expect is: "This experiment reduced noise
> to the point where the customer doesn't care about what's
> left over." It may still fail miserably in the DO-160
> lab. Just because the original observer is satisfied with
> the outcome does not mean all future observers will share
> the perception.
OK, fair enough. My investment is time while waiting for another report from you,
and some $150 for the lights. Should I, and maybe others, contribute to expenses
of this experiment? Having an off-the-shelf, sub $200 landing light pair
should be of interest to a few others as well. And yes, no guarantee for noise
levels.
>>
>> Also, I'm interested in as much light as I can get for an emergency off-field
landing and when taxiing around in the dark.
>
> Okay, your design goals call for LOTS of light
> but in situations that may amount to 0.0001%
> and 1.0% of total operations respectively.
> These may be situations wherein noise is the
> last of your worries.
Agreed, in the case of an off-field landing and taxiing, noise isn't a great concern.
But not so for the always-on flood light, and admittedly, that's a nice-to-have.
Thanks,
Holger
Message 14
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Subject: | WigWag's resistors for HID circuit |
Bob,
I had not considered a spike coming back from the input of the ballast.
Could flashing the HID's (properly pre-heated or not) damage other
electronic equipment onboard the typical aircraft, ie expensive radios and
Nav stuff?
I would like to try the flasher from B and C.
Can you point me to a source for suitable resistors?
I look forward to the results of your experimentation with the HIDs.
Thanks
Bevan
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Tuesday, March 12, 2013 8:23 AM
Subject: Re: AeroElectric-List: WigWag's resistors for HID circuit
--> <nuckolls.bob@aeroelectric.com>
At 12:29 AM 3/12/2013, you wrote:
Bob,
I have two 55watt HID for landing lights. I bought the following flasher
which failed after a few minutes of run time. See,
http://sos-production.s3.amazonaws.com/docs/ETHFSS-SP.pdf
I then ordered the heavy duty version, but had the same result. See,
http://sos-production.s3.amazonaws.com/images/ETHDSS-SP%20Fold%20A.pdf
I now see B and C sells one (which I plan to order) and notice that the
wiring diagram (when using LED or HID) has a couple 75 ohm resistors added
to the circuit. I don't know what these are for but wonder if they are to
protect the solid state flasher. If so, perhaps I should have used
something similar with my first product? Can you describe the function of
the resistors?
Are these truly (H)ight(I)intensity(D)ischarge lamps?
In other words, do they come with ballasts to convert the 14v DC to high
voltages necessary for their ignition and operation? If so, have they been
characterized for performance in a wig-wag system? ALL HID lamps have a
'warm up' period of 30 seconds to a minute after first power wherein their
light output increases and stabilizes. They probably should not be flashed
during this period of time. After that, it seems that flashing is tolerated
well and their operating temperatures stay adequately warm with a 50% duty
cycle of operation.
If your 'lamps' were killing solid state flashers I suspect inductive
reaction from the ballasts produced spikes that exceed voltage ratings on
the flasher's output transistors. It's unlikely that the transistors failed
due to an over current situation. The fact that they ran for several minutes
suggests a "pecking away" at the transistors with a succession of events.
A relay flasher like the B&C product would not be vulnerable to this kind of
failure. The resistors were added to accommodate the flasher's original
design goals to service incandescent lamps.
The flasher would not function with LED lamps.
HID lamps are a third and entirely different issue. You probably WILL need
the resistors.
Solid state flashing would be preferred but you'd want to identify root
cause for the failures and fix it. The open source flasher we did for leds
is fitted with spike suppression on the output transistors. This product
might do the job for you. I could send you one to try out. But in any case,
I would always operated the lamps at Full-ON for about a minute before
reverting to the wig-wag mode.
It occurs to me that we could do a HID version of this flasher that
automatically forces a one-minute warm up period before allowing wig-wag
operations to commence. I'd have to consult my software guru on that. In the
mean time, you could conduct the experiment to see if my design goals for
the LED/Incandescent technologies are sufficiently robust to handle your HID
fixtures. If you want to try the relay-flasher from B&C, DO add the
resistors.
Actually, I have a couple of HID conversion kits that I tried on my Kia last
year and reverted back to incandescent. I'll drag those out and see how they
behave on my bench first.
Bob . . .
Message 15
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Subject: | Help need for Wrapping Machine with Built-In Scale |
I'm interested in Wrapping Machine with Built-In Scale. I want to use it to automize
my stretch wrapping application. Tell me about load size and capacity of
maximum load weight. What is best name of the brand the the location to buy it?
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=396143#396143
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