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Jeff Wisnia Jeff Wisnia is offline
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Default 3-way switch question

Don Young wrote:

"Jeff Wisnia" wrote in message
...

Marilyn & Bob wrote:


"Jeff Wisnia" wrote in message
om...


mm wrote:



On Sun, 18 Mar 2007 14:13:05 -0400, mm
wrote:




It sounds like Terry and Joe have found you a switch, but I wanted to
point out that 3-way switches can be wired more than one way, and if
yours was wired so that one wire from the switch you could see ran
straight to the light, was hot when on and cold when off, you could
just put a little neon light between that wire and ground.

And you'd need a resistor in series with the neon light too.



I mean, that wire and neutral. I'm used to using tv words, where the
ground is used.

You COULD cheat and connect it to ground, the current drawn by the neon
is only a couple of milliamps, probably not even enough to trip a GFCI
panel breaker feeding the circuit.

But that wouldn't be up to code, so I won't suggest doing it. G

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.98*10^14 fathoms per fortnight.


Regular illuminated switches work this way (i.e. neon bulb in switch
powered without neutral--i.e. hot and ground) so why would it not meet
code to do it outside the switch?



I think the "regular illuminated switches" you're referring to are only
illuminated when the light controlled by the switch is OFF.

Their illumination is generally required to help you locate the switch "in
the dark", and once the light it controls is lit, you can see the switch
fine so it doesn't need to be illuminated.

Those switches work by putting a little neon bulb and series resistor
right across the switch contacts. Thus, when the contacts are open, the
couple of milliamps of current needed to light the neon bulb flows through
whatever load the switch is controlling (most likely a light bulb) to
neutral.

Capice?

Jeff

--



The same type of small neon lamp (with resistor) can be connected between
the travelers at either switch or at both. It will light whenever the
controlled light is off. It may glow slightly when the light is on,
depending on the capacitance and leakage of the travelers, but if so a small
resistor in parallel with it will eliminate that.

Don Young



Good point Don.

And since the OP wasn't specific in saying the pilots had to light in
phase with the garage light, his operative words being, "Looking for
some means to identify if the light actually on", your way would satisfy
his request.

Though, I'd expect most folks would prefer to have a LIT pilot to clue
them that the garage light is still on. G

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.98*10^14 fathoms per fortnight.