Today's Message Index:
----------------------
1. 03:29 AM - Re: This switch OK? (tomcostanza)
2. 04:21 AM - Strobe noise (Sam Hoskins)
3. 05:24 AM - This switch OK? ()
4. 05:51 AM - Re: Strobe noise (Robert L. Nuckolls, III)
5. 06:48 AM - Re: This switch OK? (johngoodman)
6. 07:23 AM - Re: Re: This switch OK? (Robert L. Nuckolls, III)
7. 08:36 AM - Re: Battery charging (Speedy11@aol.com)
8. 08:43 AM - Re: This switch OK? (johngoodman)
9. 09:10 AM - Re: Re: This switch OK? (Robert L. Nuckolls, III)
10. 10:20 AM - Re: This switch OK? (user9253)
11. 11:49 AM - Re: Re: This switch OK? (Ken)
12. 06:47 PM - Re: Re: This switch OK? (jerb)
13. 06:54 PM - Re: Re: This switch OK? (jerb)
14. 06:56 PM - Re: This switch OK? (johngoodman)
15. 08:39 PM - Re: This switch OK? (user9253)
16. 09:41 PM - Re: Re: This switch OK? (Robert L. Nuckolls, III)
Message 1
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Subject: | Re: This switch OK? |
> Remember...
>
> Switches manufactured in the UK will not work in any north American aircraft
> (certified or amateur built) as the current flow requirement is OPPOSITE to
> what we consider normal. This is why many switch configurations in the UK
> call for switch orientation to be up to be OFF and down to be ON.
Is this because of that Coriolis thingy? I thought things only went backwards
in the southern hemisphere.
Do not archive
--------
Clear Skies,
Tom Costanza
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=289167#289167
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I am getting a lot of strobe noise in my headset and was hoping we could
work through this. It is so bad that I cannot fly with the strobes on. Here
are the basics:
Aircraft: all composite Quickie Q-200 <http://www.samhoskins.blogspot.com/>
SkyBrite strobes/position lights http://www.airplanegear.com/skybright.htm
Wing tip lights. Power supply is mounted on the right fuselage wall, right
bebeath the rear wing.
Radio: ICOM A210
http://icomamerica.com/en/products/avionics/panelmount/a210/default.aspx
Antenna: Bob Archer com antenna model SA-006, mounted on left side of
fuselage, just aft of the rear wing.
http://www.chiefaircraft.com/airsec/Aircraft/Antennas/ArcherSportcraft.html
The distance between the power supply and the antenna is perhaps four feet.
The Skybrite installation instructions call for using "*Strobe Extension
Cables (light-duty, 3-conductor, 18 gauge, shielded)" *made from that heavy
PVC stuff. I could not route this cable through the confines of my wing, so
I used smaller diameter 3 conductor, shielded, 20 gauge, Tefzel wire.
Symptom: When the strobes are on, there is an overall kind of a white noise
background and the shoowp-swoowp kind of pulsing noise of the strobes. I
can't make it go away with the squelch control, even jacked all the way up.
On Bob's suggestion, I removed the strobe PS input and supplied the 12V with
a battery positioned right next to the PS. It seemed to help a tiny bit,
but still no joy.
Any more suggestions? Nothing is easy to do on this plane, and everything
is hard to get at. I cannot fit a vertical antenna in the tail, since it is
already built.
Thanks,
Sam
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3/4/2010
Hello Bevan, You wrote:
1) "......as the current flow requirement is OPPOSITE to what we consider
normal."
{Response} Yes, it is those perverse European electrons that cause this
problem. You can imagine what a nuisance it is for all those airplanes
flying across the Atlantic ocean to have to reposition all of their switches
when they go from one electron area to the other.
2) " This is why many switch configurations in the UK call for switch
orientation to be up to be OFF and down to be ON."
{Response} Some recalcitrant European homebuilders have even been known to
install their switches up side down to avoid this problem. Please don't
alert the European homebuilder police to this pernicious activity.
3) "Keep yur sticks on the ice."
{Response} Strange advice. All of my girl friends and even some of my wives
have insisted that I keep my stick in my pants.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
DO NOT ARCHIVE
==============================================
Time: 09:47:14 PM PST US
From: "B Tomm" <fvalarm@rapidnet.net>
Subject: RE: AeroElectric-List: Re: This switch OK?
Remember...
Switches manufactured in the UK will not work in any north American aircraft
(certified or amateur built) as the current flow requirement is OPPOSITE to
what we consider normal. This is why many switch configurations in the UK
call for switch orientation to be up to be OFF and down to be ON. :)
Just trying to help. We're all in this together. Keep yur sticks on the
ice.
Bevan :)
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Subject: | Re: Strobe noise |
At 06:14 AM 3/4/2010, you wrote:
>I am getting a lot of strobe noise in my headset and was hoping we
>could work through this. It is so bad that I cannot fly with the
>strobes on. Here are the basics:
>
>Aircraft: all composite <http://www.samhoskins.blogspot.com/>Quickie Q-200
>
>SkyBrite strobes/position lights
><http://www.airplanegear.com/skybright.htm>http://www.airplanegear.com/skybright.htm
>Wing tip lights. Power supply is mounted on the right fuselage
>wall, right bebeath the rear wing.
>
>Radio: ICOM A210
><http://icomamerica.com/en/products/avionics/panelmount/a210/default.aspx>http://icomamerica.com/en/products/avionics/panelmount/a210/default.aspx
>
>Antenna: Bob Archer com antenna model SA-006, mounted on left side
>of fuselage, just aft of the rear wing.
><http://www.chiefaircraft.com/airsec/Aircraft/Antennas/ArcherSportcraft.html>http://www.chiefaircraft.com/airsec/Aircraft/Antennas/ArcherSportcraft.html
>
>The distance between the power supply and the antenna is perhaps four feet.
>
>The Skybrite installation instructions call for using "Strobe
>Extension Cables (light-duty, 3-conductor, 18 gauge, shielded)" made
>from that heavy PVC stuff. I could not route this cable through the
>confines of my wing, so I used smaller diameter 3 conductor,
>shielded, 20 gauge, Tefzel wire.
>
>Symptom: When the strobes are on, there is an overall kind of a
>white noise background and the shoowp-swoowp kind of pulsing noise
>of the strobes. I can't make it go away with the squelch control,
>even jacked all the way up.
>
>On Bob's suggestion, I removed the strobe PS input and supplied the
>12V with a battery positioned right next to the PS. It seemed to
>help a tiny bit, but still no joy.
Do you have an audio system of any kind? Intercom?
Does radio volume control knob affect what noise
you hear? Do you hear the noise with the antenna
disconnected from the back of the radio? Do you
hear the noise on a hand-held radio while seated
in the cockpit (tune to unused frequency an open
the squelch)?
Bob . . .
>Any more suggestions? Nothing is easy to do on this plane, and
>everything is hard to get at. I cannot fit a vertical antenna in
>the tail, since it is already built.
>
>Thanks,
>
>Sam
Bob . . .
////
(o o)
===========o00o=(_)=o00o========
< Go ahead, make my day . . . >
< show me where I'm wrong. >
================================
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Subject: | Re: This switch OK? |
I'd like to thank everybody for the interest - I've learned a lot about switches
(g).
I've moved on from that switch to possibly this one, but I still need to find out
the actual amps on the Coil first:
Included:
1 x Clear Illuminated Button
1 x Protector Cover
1 x Label Sheet (Water Spray, Wipers, Lights, Nitrous, Fan, etc.)
Specifications:
Switch Acutation Style: Push Button
Circuit Activation: Constant
Lighted: Yes (White)
Amp Rating: 10A
Volt Rating: 30VDC
Terminal Type: Blade
Material: Plastic
Quantity: Sold Individually
Mounting Size: 16mm or 5/8"
John
--------
#40572 QB. Engine on, wing attach coming soon. Panel delivery soon.
N711JG reserved
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=289193#289193
Attachments:
http://forums.matronics.com//files/ign_6000_c_288.jpg
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Subject: | Re: This switch OK? |
At 08:46 AM 3/4/2010, you wrote:
><johngoodman@earthlink.net>
>
>I'd like to thank everybody for the interest - I've learned a lot
>about switches (g).
>I've moved on from that switch to possibly this one, but I still
>need to find out the actual amps on the Coil first:
It would sure help if we understood exactly what
this switch is supposed to do. Do you need
push-on, push-off (alternate action) or simply
push-on (momentary but spring loaded to off).
Exactly how does the switch under study integrate
into your airplane . . . and is there a reason
it shouldn't be but one of several switches that
accomplish different tasks? Like one of a row
of switches that control DC power, landing lights,
nav lights, etc.
In other words, why this decidedly odd
device in a machine that will undoubtedly have
several other switches?
Bob . . .
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Subject: | Re: Battery charging |
Ira,
I agree on all points.
It is a shame to waste money. But, as Bob reasoned, one can either do
capacity checks or replace batteries before they reach their service life. I
choose to replace. Laziness on my part, perhaps. For me, it is the better
option. On my VFR Pacer, I run the battery until it dies. On my
electrically-dependent IFR RV, I change the batteries every year - although I
may
switch to 2 year replacements.
I also frequently disagree with Bob - not so much on electric issues, but
on philosophy. I still respect and consider his opinions.
It is also nice to have other experts, such as yourself, comment on this
forum.
Regards,
Stan Sutterfield
Do not archive
Just changing batteries annually because you don't choose to learn about
batteries (Not talking about anyone individually here) is a shame. Money
is tight all around and frequent changes ignores the real possibility of
infantile failure which is just as likely in the real world as premature
failure
if the products are made in the far, far east.
Sometimes experts disagree. This is Bob's group and I respect that.
I appreciate his public service in dealing with the underending series
of questions. There are also other opinions formed on reasonably
solid foundations of knowledge and experience that may differ
however because some experts place different priorities on different
aspects of a project. Look for example on the scrap between Nuckolls
and Richter a few years ago.
I was once an E.E., I spent 8 years in school and grad school, I
try to keep up with the literature and I hand built my plane and panel.
Ergo, I have opinions and they are not always the same as Bob's.
Is is certainly not a dis at Bob when I think there are better places to
spend money than changing out batteries that should be fairly fresh.
Message 8
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Subject: | Re: This switch OK? |
> It would sure help if we understood exactly what
> this switch is supposed to do. Do you need
> push-on, push-off (alternate action) or simply
> push-on (momentary but spring loaded to off).
>
> Exactly how does the switch under study integrate
> into your airplane . . . and is there a reason
> it shouldn't be but one of several switches that
> accomplish different tasks? Like one of a row
> of switches that control DC power, landing lights,
> nav lights, etc.
>
> In other words, why this decidedly odd
> device in a machine that will undoubtedly have
> several other switches?
>
> Bob . . .
I guess some explanation is in order, sorry about that. I'm looking for a unique
switch for Coil Power for my GearedDrives LS1 engine. The panel has a VP200
and no other switches except two battery switches that look just like the VP200
switches (autopilot does have a couple of micros).
The reason for a Coil switch is that I need a quick way to kill the engine. There
is no key, and the VP takes care of starting. Otherwise I would have to remove
power from the battery busses to stop the engine at the end of the flight.
This would kill everything at once, unless I did some power isolation first.
So, I'm looking for a Latching Pushbutton, preferably lit when on. It needs to
be obvious to the passengers that it powers the engine. In reality, I think it
only draws about 3 amps, 5 at most. Think of it as the "run" position of your
keyed ignition.
Hope this helps.
John
--------
#40572 QB. Engine on, wing attach coming soon. Panel delivery soon.
N711JG reserved
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=289217#289217
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Subject: | Re: This switch OK? |
>
>I guess some explanation is in order, sorry about that. I'm looking
>for a unique switch for Coil Power for my GearedDrives LS1 engine.
>The panel has a VP200 and no other switches except two battery
>switches that look just like the VP200 switches (autopilot does have
>a couple of micros).
>The reason for a Coil switch is that I need a quick way to kill the
>engine. There is no key, and the VP takes care of starting.
>Otherwise I would have to remove power from the battery busses to
>stop the engine at the end of the flight. This would kill everything
>at once, unless I did some power isolation first.
>So, I'm looking for a Latching Pushbutton, preferably lit when on.
>It needs to be obvious to the passengers that it powers the engine.
>In reality, I think it only draws about 3 amps, 5 at most. Think of
>it as the "run" position of your keyed
>ignition.
What do your other switches look like? Are
they all the same kind of switch? Are there
other switches that go to control of engine
accessories? Fuel pumps? Why not an identical
switch that says "IGNITION ON" when up and
"OFF" when down?
The device you're considering has a much more
complex internal mechanism than the plain-vanilla
toggle switch. You speak to "removing power from the
battery busses to stop the engine". What devices
feed from battery busses and how are they controlled
to disconnect while the airplane is parked? Is any
single feed from the battery bus required for
the engine to function . . . does that feed power
a device has a backup? You speak to "busses" . . .
so I presume you have dual batteries with 1/2 of
engine-critical loads powered from each battery . . .
how is the change-over from "primary" to "secondary"
hardware accomplished?
Bob . . .
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Subject: | Re: This switch OK? |
John,
If this switch is going to kill the engine, what will happen if the switch fails
while flying? Assuming that you have two ignition systems, there should be
one switch for each. Is that what you have planned?
Joe
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=289236#289236
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Subject: | Re: This switch OK? |
John
If like many of us here you looking for more than just a yes or no
answer, you might consider that most of us running EFI
systems do not cut ignition power to kill the engine. (I'm assuming you
have EFI) That leaves fuel in the cylinders and (same as a Lycoming) can
be a safety hazard if someone moves the prop on a hot engine. Most EFI
computers will kill the fuel before the ignition.
The next preferred shutdown method would likely be to kill power to the
electric fuel pump(s). That is what I do when I taxi in on my backup EFI
system. Anything other than a normal system shutdown can set engine
codes on some computers though.
I do control power to my secondary ignition coils through a toggle
switch but I never shutdown the engine that way.
Ken
johngoodman wrote:
> <johngoodman@earthlink.net>
>
>
>
> I guess some explanation is in order, sorry about that. I'm looking
> for a unique switch for Coil Power for my GearedDrives LS1 engine.
> The panel has a VP200 and no other switches except two battery
> switches that look just like the VP200 switches (autopilot does have
> a couple of micros). The reason for a Coil switch is that I need a
> quick way to kill the engine. There is no key, and the VP takes care
> of starting. Otherwise I would have to remove power from the battery
> busses to stop the engine at the end of the flight. This would kill
> everything at once, unless I did some power isolation first. So, I'm
> looking for a Latching Pushbutton, preferably lit when on. It needs
> to be obvious to the passengers that it powers the engine. In
> reality, I think it only draws about 3 amps, 5 at most. Think of it
> as the "run" position of your keyed ignition. Hope this helps. John
>
> -------- #40572 QB. Engine on, wing attach coming soon. Panel
> delivery soon. N711JG reserved
>
>
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Subject: | Re: This switch OK? |
Whoa there Joe,
Wow! Can't believe your saying using use AC rated switches for DC
applications at near the full AC current rating is OK. No way.
AC switches take advantage of the AC zero crossing for reducing
contact arcing and welding. (The reason DC switches amp for amp
typically cost more than AC switches, there made different to reduce
and eliminate contact arcing and welding.) And suddenly you say
using the switch the gentlemen asked about is OK and justify your
recommendation upon the spec's of a totally different switch. Use
the right type of switch for your application. Maybe you can
convince the folks that select the switches used for DC powered
landing gear applications to use AC designated switches. Just don't
think you'll quite sell them on your method.
jerb
At 06:21 PM 3/3/2010, you wrote:
>
>Looking at the picture of this switch (made in UK), the first thing
>that came to mind is that it was going to be used for a starter
>switch. It turns out that John intends to use it for a more
>critical application where a high quality switch should be used. So
>I take back what I said about the switch being ok to use.
> As a general rule, a 125VAC rated switch can handle the same
> current at 14VDC, even if the manufacturer does not publish the DC
> rating. Every AC switch has a DC ampacity. That ampacity might
> not have been determined by testing and thus is unknown.
> Jerry B. said,
> > "the DC current capacity will normally be only a fraction of it's
> AC current rating."
> That is true if the voltage remains the same: 250V in this
> case. But, generally speaking, a 125VAC rated switch can carry as
> much DC current at 14V as it can carry AC current at 125V. An
> example of this can be seen by reading the data sheet for another
> switch. http://www.nkkswitches.com/pdf/stoggleslowcap.pdf
>Notice that 125VAC rating is identical to the 30VDC rating. At
>14VDC, this switch can handle even more. Also notice that this
>switch can handle 2 1/2 times the current at 30VDC than it can at
>250VAC. Most good quality snap action AC switches are suitable for
>use in homebuilt aircraft as long as the 14VDC current does not
>exceed the 125VAC rating of the switch.
>Comments are welcome.
>Joe
>
>--------
>Joe Gores
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Subject: | Re: This switch OK? |
At 03:27 AM 3/4/2010, you wrote:
><Tom@CostanzaAndAssociates.com>
>
>
> > Remember...
> >
> > Switches manufactured in the UK will not work in any north
> American aircraft
> > (certified or amateur built) as the current flow requirement is
> OPPOSITE to
> > what we consider normal. This is why many switch configurations in the UK
> > call for switch orientation to be up to be OFF and down to be ON.
>
>Is this because of that Coriolis thingy? I thought things only went
>backwards in the southern hemisphere.
They do go backwards which is why some toilets (aka water closets)
designed to work in one hemisphere will not work or not nearly as
well if put into service in the opposite hemisphere for which they
were designed to operate which leads me to conclude this thread is
headed for the crapper. :-)
jerb
>Do not archive
>
>--------
>Clear Skies,
>Tom Costanza
>
>
>Read this topic online here:
>
>http://forums.matronics.com/viewtopic.php?p=289167#289167
>
>
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Subject: | Re: This switch OK? |
Sorry that I've got everybody wondering; I'll try to explain.
The GearedDrives LS1 Corvette engine is just like a car. In a traditional car,
the key has several positions, the last rotation is "start", and it is spring
loaded to come out of start to "run." The "run" position is Coil power. It is
not actual Coil power which is a lot of juice, just a relay out "under the hood."
When you turn off a car, you don't starve it of fuel like airplanes normally
do, you kill the coil power.
As far as my switches, The VP200 does everything with soft switches and it's switch
panel. The Master Battery and Aux Battery switches are positioned next to
the switch panel and are the same brand of switches. The two fuel pumps and the
Engine Crosstie will be on three guarded switches on the console, under the
panel, that will be normally on. See Z-19 but add a crosstie between the two
batteries, put the engine battery bus on the "on" side, but leave the Keep Alive
power for the ECU on the engine battery hot side.
There shouldn't be fuel in the cylinders because the ECU won't inject any and the
fuel rail regulator is closed. The prop is not connected to the engine because
the clutch has released around 700 rpm. You can spin the prop all you want.
Fuel is still pumping but isn't getting past the Filter/Regulator which returns
all the fuel to the tanks. Fuel can be stopped by turning off the batteries
or opening the guarded pump switches.
I'm sure a lot of you think this is wrong, but I'm really not asking. I'm only
trying to find a good Kill Switch that is so obvious that even a Cave Man Can
Do It.
I'm still amazed that a guy steered a stuck pedal Toyota for 6 miles without ever
thinking about the shift stick or the key....
John
--------
#40572 QB. Engine on, wing attach coming soon. Panel delivery soon.
N711JG reserved
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=289283#289283
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Subject: | Re: This switch OK? |
> Wow! Can't believe your saying using use AC rated switches for DC applications
at near the full AC current rating is OK. No way.
JERB,
I am not the only one who thinks that it is OK to use AC rated switches in airplanes.
Read the last paragraph on Page 2 and page 3 of this document written
by a well respected electrical guru,
http://www.aeroelectric.com/articles/Switch_Ratings.pdf
Here is a quote from that article:"
> In a nutshell, 125 VAC ratings equate favorably and conservatively to 14 VDC
ratings - as long as the switch has a healthy "snap" action . . .The switches
we stock sell for $5.00 in a single-pole device and carry no markings for DC ratings.
They are rated at 7 amps or better at 115 AC and will work just fine
in virtually every slot on an airplane panel."
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=289291#289291
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Subject: | Re: This switch OK? |
At 10:36 PM 3/4/2010, you wrote:
>
>
> > Wow! Can't believe your saying using use AC rated switches for DC
> applications at near the full AC current rating is OK. No way.
All switches have ac and dc capabilities at some level.
Just because the ratings on the printed on the side of
the switch are given at 120 or 240 VAC simply speaks
to the largest market into which they are sold. It
doesn't mean that they don't have useful and quite
rational application in DC systems. The comparative
ratings charts for switches in any well written
switch catalog will confirm this assertion.
The voltage rating of a switch is driven mostly by
it's ability to break a circuit . . . spread the
contacts fast enough so that the fire goes out
before damage is done. The intensity of that fire
is proportional to the current in the circuit at
the time the contacts open.
So a switch with contacts that don't overheat at
7A will CARRY that much current at any voltage but
the current may have to be de-rated at the higher
DC voltages . . . because it's harder to put the
BREAK the circuit without generating a lot of heat.
Bob . . .
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