wrote in message
ups.com...
I have what seems to be something wrong with a 3 way switch on the
light at the top of my stairs. This light can be turned off/on from
the bottom of the stair as well as from the top.

I was replacing the fixture at the top of the stair and turned the
power off at the switch thinking that I would be safe to replace the
fixture. After removing the screws holding the fixture to the ceiling
I checked the light with my greenlee gt-11 voltage detector and was
surprised to hear the unit ringing. I broke out the DVM and sure
enough 92 volts between the white and black wires to the fixture.

Turning on the light the voltage goes to 120vac, off back to 92vac.

So something seems very wrong, I went to the panel and turned off the
breaker and changed out the fixture. I am now glad I was lazy and did
it the wrong way first.

I don't understand why the incandecent bulb did not light at 92
volts. I have replaced the bulb with a CF as that is what we are
doing throughtout the house.

About the house:
1957 cape 2 wire hot/neutral with no ground for all parts of the
house. Any new work has been done with romex in proper gauges for
circuits.
5 years ago we had the 100Amp fuse panel replaced with a 200 amp
breaker panel.

Any common problems that might cause this?
Am I using electricity even though the light is off?

Thanks!
e


Couldn't this be possible with a shared neutral? The reason I ask is because
I was changing a fixture the other day for a woman, had the switch off (this
was just a single pole switch), unscrewed the fixture and checked the wires
with one of those pen like non contact voltage testers and there was still
juice. I figured it must just be a false reading so I took the wirenuts off
(the hot only had one wire with it in the wire nut and the neutral had two).
When I took the neutral wire nut off the wires came apart and arced a bit. I
thought it was strange, so I kept touching them together and pulling them
apart and noticed the clock on the microwave was turning on and off so I
shut off the microwave breaker too and the voltage went away. When I got
to the hallway fixture, same type of thing, tester read voltage pulled off
the wire nuts this time the neutral arced good with a nice sounding pop.
Turns out the hallway neutral was being shared with the computer room
neutral and being that the computer was drawing more current then the
microwave clock circuit I got a bigger arc until my disconnecting them
turned off the computer. This is just another thought because I don't know
if the OP posted whether he just test from neutral to hot or hot to ground
or neutral to ground. By the way this house was wired in 72 and I am not
sure if it was standard practice back then to share a neutral without a
double pole breaker, but I would imagine there are other circuits in there
that are wired this way.

Shane