I'm trying to wire 3-way switches on either side of a ceiling lamp. The
power initiates at one of the switches. I've got the wiring scheme figured
out but I have a problem.



Prior to installing the lamp fixture I decided to check the switch functions
(at the ceiling lamp) with this simple $ 1.00 neon tester. With the switch
on the neon tester gives full brightness, with switch off it still lights
up, but very dim.



Disconnected all of the wires everywhere and come up with the following:



At 3-way switch I have a ground, black, red & white wire (only the ground
and the white have been connected to others). I'll call the black and red
wire "shuttle wires". These same wires are dangling, unconnected, at the
ceiling. Nothing is hooked up. Ground to power is 118.5v. White to power
is 118.5v. Ground to white is 0v. IF I connect the "shuttle" black to
power (as if the switch would also do) I get 30± volts on the totally
disconnected (both ends) red "shuttle" wire. An ohm reading between the
unconnected "shuttle" wires reads open (my ohm meter only goes to 20
megohms).



Is the only answer that somewhere in the wall the black and red "shuttle"
wires have slightly shorted, giving me 30± volts? These are brand new walls
in finished space and I'd hate to tear out the sheetrock and wires. Note
that all of the above is with the 3-way switches in my pockets, i.e.,
totally out of the equation.



BTW, if I ignore all of the above, I get 60±volts at the ceiling in the
switch off position. Turning either switch to the on position gives me my
118.5v. The 60 volts is not enough to light a bulb, so, I am tempted to
ignore it. Is this dangerous?



All advice greatly appreciated.





Ivan Vegvary

The voltages that you are seeing are probably caused by capacitive
coupling in the switches or wiring. In addition to the normal DC and AC
connectivity of a switch in the closed position, there is some AC
coupling in a switch across the open terminals, and AC coupling between
wires in a bundle. A neon test light probably draws very little
current, so it may be lighting due to this capacitive coupling. In
other words, it may be that nothing is wrong.

The voltages you are reading with a voltmeter are even less surprising,
even though the switches were in your pocket. Most modern voltmeters are
very high impedence, and find all kinds of voltages that have virtually
no current or power associated with them, even when the probes are just
lying around, touching nothing. The test lights are somewhat lower
impedence, so usually are more helpful. The capacitive coupling is
probably occuring from one wire to the other. These wires are probably
in the same bundle, so one wire capacitively couples a little voltage to
the other.

Hook up the light the way that you think that it should be hooked up,
screw in a light bulb, and try the switches. If the light works the way
you expect it to, forget it.

If you want to check for wires shorting in the wall, do it this way:
Disconnect all wires in the bundle at both ends. Use an ohmmeter to
check the wires for DC conductivity. They should all be open (very high
resistance, probably relative to each other. If the readings seem
flaky or indicate a problem, kill all the AC power in the house and
repeat the ohmeter readings. I would be surprised if you had a short,
but it is possible that a nail ran through the wire bundle, or something
else strange happened.

This is another case of a little knowledge and test equipment being a
dangerous thing. The more you check, the more confused you get, because
you are seeing very marginal effects, and then assuming that you have
some sophisticated problem. Don't take it personally, electricity is
simple at first glance, but gets more complex the closer you study it.
Electricians just wire it up, and are happy if everything lights up, and
probably only pull out the voltmeter if there is a problem.

Richard



Ivan Vegvary wrote:

I'm trying to wire 3-way switches on either side of a ceiling lamp. The
power initiates at one of the switches. I've got the wiring scheme figured
out but I have a problem.

Prior to installing the lamp fixture I decided to check the switch functions
(at the ceiling lamp) with this simple $ 1.00 neon tester. With the switch
on the neon tester gives full brightness, with switch off it still lights
up, but very dim.

snip

Ivan:

Though there may be other reasons for getting the measurements you see, I would
propose the following:

You are probably measuring the voltage with a high impedance voltmeter, which
doesn't put much load on the circuit under test. With a decently long run of
wires running parallel, they act much like a transformer, which means that you
will put an actual 117 (or so) volts on the hot wire, and induction will cause
the floating wire to have a voltage induced on it. However, the amount of
current available on the floating wire is extremely low. So low, in fact that
it won't be able to cause a problem.

If you were to connect two light bulbs to the "shuttle wires" you'll find that
when you apply 117 to the red wire, the bulb connected between the red and white
wires will illuminate, and the voltage on the black wire will be zero. If you
apply 117V to the black wire, the bulb connected between the Black and White
wires will illuminate and the voltage on the red wire will be zero.

Given a high impedance meter (or neon bulb) you can get odd indications,
particularly if the run of wires is long, which increases the efficiency of the
"single turn transformer" that is being created.

Now, the above explanation assumes that when you made your measurements, you
verified that the "Shuttle Wire" cabling doesn't go anywhere else than between
the two switch locations and the light.

From your description, it sounds like things were actually wired correctly
(using a multi-color, 4-wire cable) instead of the slipshod stuff I've run
across over the years.

What I would expect to see is a 3-wire (Ground, Black, White) cable coming into
your "hot" swichbox from the breaker panel, and another cable with 4-wires
(Ground, Black, Red, White) going to the lamp fixture box in the ceiling. From
the Ceiling box there will be another 4-wire cable (Ground, Black, Red, White)
going to the remote switchbox. At the hot switchbox, the Ground and White wires
are connected to the Ground and White wires of the 4-Wire Cable and the ground
wire should be connected to the box and/or ground terminal of the switch. The
Black wire of the 3-wire cable goes to the common point of the 3-way switch, and
the black and red wires of the 4-way cable go to the alternating contacts of the
3-way switch. At the ceiling box, the ground, black, and white wires are each
connected to the corresponding colored wires of the remote switch cable, with
the two white wires (one from each cable) connected to the lamp fixture. The
white wire from the remote switch cable should have a wrap of colored or black
tape on it to indicate it is the "hot" wire from the remote switch. At the
remote switch box, the ground wire should be connected to the box and/or ground
terminal of the switch. The black and red wires go to the alternating contacts
of the 3-way switch, and the white wire, (which should have a wrap of colored or
black tape on it to indicate it is the "hot" wire from this switch) is
connections to the 4-wire cables, everything should work properly.

If this doesn't make sense, or you have any confusion at all, you should have a
qualified electrician come in and check everything out. It's better to be safe
and spend a few extra bucks than be dead or to cause an electrical fire because
you wired something wrong. Also, in some areas, it may be illegal for you to
do even the smallest electrical addition or change unless you are a licensed
electrician. Always be safe and follow all applicable laws and regulations in
your area.

Disclaimer: Don't do this at home. Always have a professional perform any
electrical or plumbing work. I'm not licensed to perform electrical work in
your location, so the above is for educational purposes only and not to suggest
you can actually do your own electrical or plumbing work. If you do ignore this
warning and do it yourself, don't bother to sue me because I don't have anything
to get anyway, unless you would like to take over my bills... 8-)

--Rick

Ivan Vegvary wrote:

I'm trying to wire 3-way switches on either side of a ceiling lamp. The
power initiates at one of the switches. I've got the wiring scheme figured
out but I have a problem.

Prior to installing the lamp fixture I decided to check the switch functions
(at the ceiling lamp) with this simple $ 1.00 neon tester. With the switch
on the neon tester gives full brightness, with switch off it still lights
up, but very dim.

Disconnected all of the wires everywhere and come up with the following:

At 3-way switch I have a ground, black, red & white wire (only the ground
and the white have been connected to others). I'll call the black and red
wire "shuttle wires". These same wires are dangling, unconnected, at the
ceiling. Nothing is hooked up. Ground to power is 118.5v. White to power
is 118.5v. Ground to white is 0v. IF I connect the "shuttle" black to
power (as if the switch would also do) I get 30± volts on the totally
disconnected (both ends) red "shuttle" wire. An ohm reading between the
unconnected "shuttle" wires reads open (my ohm meter only goes to 20
megohms).

Is the only answer that somewhere in the wall the black and red "shuttle"
wires have slightly shorted, giving me 30± volts? These are brand new walls
in finished space and I'd hate to tear out the sheetrock and wires. Note
that all of the above is with the 3-way switches in my pockets, i.e.,
totally out of the equation.

BTW, if I ignore all of the above, I get 60±volts at the ceiling in the
switch off position. Turning either switch to the on position gives me my
118.5v. The 60 volts is not enough to light a bulb, so, I am tempted to
ignore it. Is this dangerous?

All advice greatly appreciated.

Ivan Vegvary

Jeff Wisnia wrote:
Don't sweat it Ivan
^^^^^^^^^^^^
I am sure Jeff and Richard are correct. If you want to verify that the
voltage has no power behind it (high output impedance) place a fairly high
resistance(thousands of ohms) across your meter leads or your neon tester,
and you will see the voltage disappear. In order to be dangerous, a circuit
has to be capable of delivering power into a load.

"Richard Ferguson" wrote in message
...
Electricians just wire it up, and are happy if everything lights up, and
probably only pull out the voltmeter if there is a problem.

And if it does work, I pull out the 'scope

But then again, I'm testing things a bit more complex than a light
switch.

Speaking of scope... my Tek 475 sounds like HV arcing, and smells like
ozone. I'm guessing the 2nd anode on the CRT is dirty, tried opening
the scope but can't find any way to get at the CRT. Display and functions
appear unaffected. Ideas?

Tim

--
In the immortal words of Ned Flanders: "No foot longs!"
Website @ http://webpages.charter.net/dawill/tmoranwms

Thanks everybody!!!

I guess it was capacitance coupling. The wires are part of a bundle. This
four wire bundle is also twisted along its full length (about 15 feet) as
opposed to 2 (+ground) romex which is coiled flat. I don't know if this
makes a difference.

Anyway, the wires do not appear shorted when I test them with a volt meter.
The lightbulb does not light when placed accross this 30 volts, therefore no
amperage as stated in the replies. If I grab this 30 volt wire with a wet
fingers and the ground with the other fingers (same hand, of course) I feel
nothing. Guess there is no current.

I will sleep tonight thanks to this newsgroup.

Thanks again,
Ivan Vegvary

"Ivan Vegvary" wrote in message
news:CwFUa.153707$N7.21064@sccrnsc03...
I'm trying to wire 3-way switches on either side of a ceiling lamp. The
power initiates at one of the switches. I've got the wiring scheme
figured
out but I have a problem.



Prior to installing the lamp fixture I decided to check the switch
functions
(at the ceiling lamp) with this simple $ 1.00 neon tester. With the
switch
on the neon tester gives full brightness, with switch off it still lights
up, but very dim.



Disconnected all of the wires everywhere and come up with the following:



At 3-way switch I have a ground, black, red & white wire (only the ground
and the white have been connected to others). I'll call the black and red
wire "shuttle wires". These same wires are dangling, unconnected, at the
ceiling. Nothing is hooked up. Ground to power is 118.5v. White to
power
is 118.5v. Ground to white is 0v. IF I connect the "shuttle" black to
power (as if the switch would also do) I get 30± volts on the totally
disconnected (both ends) red "shuttle" wire. An ohm reading between the
unconnected "shuttle" wires reads open (my ohm meter only goes to 20
megohms).



Is the only answer that somewhere in the wall the black and red "shuttle"
wires have slightly shorted, giving me 30± volts? These are brand new
walls
in finished space and I'd hate to tear out the sheetrock and wires. Note
that all of the above is with the 3-way switches in my pockets, i.e.,
totally out of the equation.



BTW, if I ignore all of the above, I get 60±volts at the ceiling in the
switch off position. Turning either switch to the on position gives me my
118.5v. The 60 volts is not enough to light a bulb, so, I am tempted to
ignore it. Is this dangerous?



All advice greatly appreciated.





Ivan Vegvary

On Sun, 27 Jul 2003 01:02:26 GMT, someone who calls themselves "Ivan
Vegvary" wrote:

I'm trying to wire 3-way switches on either side of a ceiling lamp. The
power initiates at one of the switches. I've got the wiring scheme figured
out but I have a problem.

Prior to installing the lamp fixture I decided to check the switch functions
(at the ceiling lamp) with this simple $ 1.00 neon tester. With the switch
on the neon tester gives full brightness, with switch off it still lights
up, but very dim.
snip

Before I develop a migraine reading through that again, are the
switches a "Pilot light" design to light up when they are off? That
would explain some current flow through the neon pilot lights.

The switches stamped "ILLUMINATED" on the back would be a big clue.

-- Bruce --
--
Bruce L. Bergman, POB 394, Woodland Hills CA 91365, USA
Electrician, Westend Electric (#726700) Agoura, CA

WARNING: UCE Spam E-mail is not welcome here. I report violators.
SpamBlock In Use - Remove the "Python" with a "net" to E-Mail.

On Sun, 27 Jul 2003 05:21:50 GMT, "Ivan Vegvary"
wrote:
snip
amperage as stated in the replies. If I grab this 30 volt wire with a wet
fingers and the ground with the other fingers (same hand, of course) I feel
nothing. Guess there is no current.

Methinks you should develop better testing techniques - Unless, of
course, you really don't want to be around much longer, or possibly
are looking for a Darwin award.....
Ken.

Hi Bruce,
Yes, that was pretty bad reading (my post). Should have dropped the subject
of switches and merely stated that I have voltage in a wire that is
unconnected at either end. The switches are not ILLUMINATING.

Thanks again for your thoughts.

Ivan
"Bruce L. Bergman" wrote in message
...
On Sun, 27 Jul 2003 01:02:26 GMT, someone who calls themselves "Ivan
Vegvary" wrote:

I'm trying to wire 3-way switches on either side of a ceiling lamp. The
power initiates at one of the switches. I've got the wiring scheme
figured
out but I have a problem.

Prior to installing the lamp fixture I decided to check the switch
functions
(at the ceiling lamp) with this simple $ 1.00 neon tester. With the
switch
on the neon tester gives full brightness, with switch off it still lights
up, but very dim.
snip

Before I develop a migraine reading through that again, are the
switches a "Pilot light" design to light up when they are off? That
would explain some current flow through the neon pilot lights.

The switches stamped "ILLUMINATED" on the back would be a big clue.

-- Bruce --
--
Bruce L. Bergman, POB 394, Woodland Hills CA 91365, USA
Electrician, Westend Electric (#726700) Agoura, CA

WARNING: UCE Spam E-mail is not welcome here. I report violators.
SpamBlock In Use - Remove the "Python" with a "net" to E-Mail.

Bruce L. Bergman wrote: (clip) are theswitches a "Pilot light" design to
light up when they are off? That would explain some current flow through
the neon pilot lights (clip)
^^^^^^^^^^^^^
Those would have to be some very *special* switches, since they were in his
pocket while all this was going on. :-)

"Bruce L. Bergman" wrote:

On Sun, 27 Jul 2003 01:02:26 GMT, someone who calls themselves "Ivan
Vegvary" wrote:

I'm trying to wire 3-way switches on either side of a ceiling lamp. The
power initiates at one of the switches. I've got the wiring scheme figured
out but I have a problem.

Prior to installing the lamp fixture I decided to check the switch functions
(at the ceiling lamp) with this simple $ 1.00 neon tester. With the switch
on the neon tester gives full brightness, with switch off it still lights
up, but very dim.
snip

Before I develop a migraine reading through that again, are the
switches a "Pilot light" design to light up when they are off? That
would explain some current flow through the neon pilot lights.

The switches stamped "ILLUMINATED" on the back would be a big clue.

-- Bruce --
--
Bruce L. Bergman, POB 394, Woodland Hills CA 91365, USA
Electrician, Westend Electric (#726700) Agoura, CA

WARNING: UCE Spam E-mail is not welcome here. I report violators.
SpamBlock In Use - Remove the "Python" with a "net" to E-Mail.

Even though you're an electrician Bruce, I'll stick my neck out and ask, "Do they
even *make* 3-way switches with pilot lamps in them?".

Not impossible, but it's take some fancy wiring to make those neon pilot lamps
light up when the switches are "off", wouldn't it?

Jeff

--

Jeff Wisnia (W1BSV + Brass Rat '57 EE)

"I before E except after C"....(The height of insufficient weird ancient
science...)

"Jeff Wisnia" wrote in message
...


"Bruce L. Bergman" wrote:

On Sun, 27 Jul 2003 01:02:26 GMT, someone who calls themselves "Ivan
Vegvary" wrote:

I'm trying to wire 3-way switches on either side of a ceiling lamp.
The
power initiates at one of the switches. I've got the wiring scheme
figured
out but I have a problem.

Prior to installing the lamp fixture I decided to check the switch
functions
(at the ceiling lamp) with this simple $ 1.00 neon tester. With the
switch
on the neon tester gives full brightness, with switch off it still
lights
up, but very dim.
snip

Before I develop a migraine reading through that again, are the
switches a "Pilot light" design to light up when they are off? That
would explain some current flow through the neon pilot lights.

The switches stamped "ILLUMINATED" on the back would be a big clue.

-- Bruce --
--
Bruce L. Bergman, POB 394, Woodland Hills CA 91365, USA
Electrician, Westend Electric (#726700) Agoura, CA

WARNING: UCE Spam E-mail is not welcome here. I report violators.
SpamBlock In Use - Remove the "Python" with a "net" to E-Mail.

Even though you're an electrician Bruce, I'll stick my neck out and ask,
"Do they
even *make* 3-way switches with pilot lamps in them?".

Not impossible, but it's take some fancy wiring to make those neon pilot
lamps
light up when the switches are "off", wouldn't it?

Jeff

--

Jeff Wisnia (W1BSV + Brass Rat '57 EE)

"I before E except after C"....(The height of insufficient weird ancient
science...)


I have several of them
the neon bulb is in series with the light bulb in the fixture when the
switch is off

Thompson Family wrote:

"Jeff Wisnia" wrote in message
...


"Bruce L. Bergman" wrote:

On Sun, 27 Jul 2003 01:02:26 GMT, someone who calls themselves "Ivan
Vegvary" wrote:

I'm trying to wire 3-way switches on either side of a ceiling lamp.
The
power initiates at one of the switches. I've got the wiring scheme
figured
out but I have a problem.

Prior to installing the lamp fixture I decided to check the switch
functions
(at the ceiling lamp) with this simple $ 1.00 neon tester. With the
switch
on the neon tester gives full brightness, with switch off it still
lights
up, but very dim.
snip

Before I develop a migraine reading through that again, are the
switches a "Pilot light" design to light up when they are off? That
would explain some current flow through the neon pilot lights.

The switches stamped "ILLUMINATED" on the back would be a big clue.

-- Bruce --
--
Bruce L. Bergman, POB 394, Woodland Hills CA 91365, USA
Electrician, Westend Electric (#726700) Agoura, CA

WARNING: UCE Spam E-mail is not welcome here. I report violators.
SpamBlock In Use - Remove the "Python" with a "net" to E-Mail.

Even though you're an electrician Bruce, I'll stick my neck out and ask,
"Do they
even *make* 3-way switches with pilot lamps in them?".

Not impossible, but it's take some fancy wiring to make those neon pilot
lamps
light up when the switches are "off", wouldn't it?

Jeff

--

Jeff Wisnia (W1BSV + Brass Rat '57 EE)

"I before E except after C"....(The height of insufficient weird ancient
science...)


I have several of them
the neon bulb is in series with the light bulb in the fixture when the
switch is off

Sorry I'm being so obtuse about this, but could you post a diagram showing how
this works on a "3-way" switch? I understand how a neon bulb (and it's
dropping resistor) are wired inside a single pole illuminated switch and light
when the switch is open,, but the best I can sketch out for 3-way switches
needs at least two neon bulbs and two resistors inside each switch.

I wonder if the switch makers have figured out a way to do it with just one
neon bulb in the switch.

And yes, I have learned something new tonight; Leviton does list an
illuminated 3-way switch, so they obviously know how to do it.

http://www.levitonproducts.com/Catal...3.htm?PID=1208

Jeff

--

Jeff Wisnia (W1BSV + Brass Rat '57 EE)

"I before E except after C"....(The height of insufficient weird ancient
science...)

"Kenneth W. Sterling" wrote:

On Sun, 27 Jul 2003 05:21:50 GMT, "Ivan Vegvary"
wrote:
snip
amperage as stated in the replies. If I grab this 30 volt wire with a wet
fingers and the ground with the other fingers (same hand, of course) I feel
nothing. Guess there is no current.

Methinks you should develop better testing techniques - Unless, of
course, you really don't want to be around much longer, or possibly
are looking for a Darwin award.....
Ken.

Nah, I'm reminded of a british prof who tought our sophmore course titled
"Rotating Machinery", circa '54. (That was just a fancy name for motors,
generators and such.)

Lots of 208/3-phase all over the place, slate panels with big unguarded knife
switches and exposed tapered pin and sleeve cable connectors.on them. OSHA would
have crapped in their collective pants if they'd been around back then.

I'll never forget him telling us early on that we'd never "make it" as engineers
until we learned to "take" a shock.

He also wisely tought us the "One arm behind your back" tactic to keep those
shocks from running through our chests, which may explain why I'm still around
to write this.

Jeff

--

Jeff Wisnia (W1BSV + Brass Rat '57 EE)

"I before E except after C"....(The height of insufficient weird ancient
science...)

In article , Jeff says...

Sorry I'm being so obtuse about this, but could you post a diagram showing how
this works on a "3-way" switch?

But of course:
o--------------------o
/ |
H-----------------o O o-------------Lamp---N
| /
o--------------------o

They put the pilot light between the two poles of the switch.
Interestingly the tiny bit of current that flows when the
light is 'on' is due to the exact stray capacitence that
started this thread!

Jim

==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
==================================================

In article , jim says...

But of course:

Well. That ascii art didn't work out at all. But the
essence of the explaination is correct:

They put the pilot light between the two poles of the switch.
Interestingly the tiny bit of current that flows when the
light is 'on' is due to the exact stray capacitence that
started this thread!

==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
==================================================

In article ,
says...
Sorry I'm being so obtuse about this, but could you post a diagram showing how
this works on a "3-way" switch? I understand how a neon bulb (and it's
dropping resistor) are wired inside a single pole illuminated switch and light
when the switch is open,, but the best I can sketch out for 3-way switches
needs at least two neon bulbs and two resistors inside each switch.

I wonder if the switch makers have figured out a way to do it with just one
neon bulb in the switch.


Put the neon lamp and resistor in series between the NO and
NC terminal of each 3-way switch. Won't that work?

How about a 4-way switch?

Ned Simmons

On Sun, 27 Jul 2003 21:51:47 -0400, Ned Simmons
wrote:


Ned Simmons
From the Leviton page, they are obviously using two neon lamps, one
connected from each messenger wire to ground. Press the illuminated
end of the toggle and the controlled light comes on or is extinguished
and the other neon is powered.
Gerry :-)}
London, Canada

In article ,
says...
In article , jim says...

But of course:

Well. That ascii art didn't work out at all.

Looks OK here (but you beat me to it by 3 minutes).

Ned Simmons

jim rozen wrote:

In article , jim says...

But of course:

Well. That ascii art didn't work out at all. But the
essence of the explaination is correct:

They put the pilot light between the two poles of the switch.
Interestingly the tiny bit of current that flows when the
light is 'on' is due to the exact stray capacitence that
started this thread!

==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
==================================================

OK here. Maybe you should give up thos stupid M$ fancy fonts.

Ted

In article , Ned says...

How about a 4-way switch?

Unless the 4-way switch in the center of the run has
pilot lamps, the ones at the end won't really work
right.

But I think this works if you draw two pilot lamps
on the four-way switch. That is, if you draw the
switch as four dots, and the center contacts either
go straight thru or reverse, then the lamps have
to be in the switch in such a way to make them in
series with the messenger wires.

Jim

==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
==================================================

On Mon, 28 Jul 2003 03:41:18 GMT, someone who calls themselves Jeff
Wisnia wrote:
jim rozen wrote:
In article , Jeff says...

Sorry I'm being so obtuse about this, but could you post a diagram showing how
this works on a "3-way" switch?

But of course:
o--------------------o
/ |
H-----------------o O o-------------Lamp---N
| /
o--------------------o

They put the pilot light between the two poles of the switch.
Interestingly the tiny bit of current that flows when the
light is 'on' is due to the exact stray capacitence that
started this thread!

But of course!

Now, why didn't I think of that? Good thing I hung up my scope 5 years ago...

Saved me the trouble of doing the ASCII Art myself. The two wires
in the middle are referred to as travelers, and there really isn't a
defined NO or NC on the 3-way switches.

The pilot light in the switch is between the two travelers (you can
use multiple lighted 3-way and 4-way switches in the same circuit),
and they send the pilot light current through the ceiling light
filament - remove that big lamp, and all the pilot lights in the
switches go out.

When you check the circuit with the power applied & the lamp removed
with a high-impedance meter, it looks like there's voltage at the lamp
socket all the time, no matter which way you flip the switches...

That's when you take a step back and think"Sumthin's Wrong Here!"
(sic ;-) and re-check all your assumptions. (And find out that they
used lighted switches.)

-- Bruce --
--
Bruce L. Bergman, POB 394, Woodland Hills CA 91365, USA
Electrician, Westend Electric (#726700) Agoura, CA

WARNING: UCE Spam E-mail is not welcome here. I report violators.
SpamBlock In Use - Remove the "Python" with a "net" to E-Mail.

In article , Bruce says...

The pilot light in the switch is between the two travelers (you can
use multiple lighted 3-way and 4-way switches in the same circuit),
and they send the pilot light current through the ceiling light
filament - remove that big lamp, and all the pilot lights in the
switches go out.

Right, but the present question is, how do they implement
the pilot light at the four-way switch? Seems to me they
really would need two neon lamps there to make it work.

Jim

==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
==================================================

In article ,
says...
In article , Bruce says...

The pilot light in the switch is between the two travelers (you can
use multiple lighted 3-way and 4-way switches in the same circuit),
and they send the pilot light current through the ceiling light
filament - remove that big lamp, and all the pilot lights in the
switches go out.

Right, but the present question is, how do they implement
the pilot light at the four-way switch? Seems to me they
really would need two neon lamps there to make it work.


If you connect a single pilot light between the travelers
on either side of the 4-way switch, it will be in parallel
with the the pilot light at the 3-way wired to that side of
the switch, so only one lamp needed at each switch.

I went thru the exercise of following the flow thru the
various states of the switches before seeing the obvious.
Doh!

Ned Simmons

In article , Ned says...

If you connect a single pilot light between the travelers
on either side of the 4-way switch, it will be in parallel
with the the pilot light at the 3-way wired to that side of
the switch, so only one lamp needed at each switch.

Grrr, why didn't I see that to start! If one did put
two lamps in the four way switch, one would be on at
all times!

Thanks for the explaination!

Jim

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