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KCPumpkinStalker
Stray voltage when switch is off

1935 storybook cottage

I replaced my bathroom light fixture, wall mount over the mirror. There were several wires that were twisted together in the box and when the wall switch is on, I got 119V. However, when the wall switch was off, I got 18.4V on my Fluke. The wall switch was replaced by an electrician with a GFI switch/outlet combo.

I'm guessing the reason there are 4 wires twisted together is one set used to go to the outlet that was commonly found on porceline bathroom light fixtures. I'm afraid if I try to twist it apart the wires will disentegrate. They're solid enough the way they are, but it looks like someone actually twisted, and then soldered them together.

So, is 18 erroneous volts really a problem? Will bulbs burn out quicker if the constantly receive a small stream of voltage? Is it worth messing with or is there a chance I'll create more problems?

NEC
Re: Stray voltage when switch is off

You are using a digital meter, correct?

What you are seeing is voltage that is induced in the wire much like how a transformer works. There is no current available to do any damage though. You could short it to a grounded conductor and not see a spark. This is very common when using a digital meter.

No problem.

KCPumpkinStalker
Re: Stray voltage when switch is off

Yes, digital meter. Thanks for the reply. I didn't figure it would cause a problem but thought I would ask just in case.

Ernie_Fergler
Re: Stray voltage when switch is off
NEC wrote:

You are using a digital meter, correct?

What you are seeing is voltage that is induced in the wire much like how a transformer works. There is no current available to do any damage though. You could short it to a grounded conductor and not see a spark. This is very common when using a digital meter.

No problem.

NEC, you beat me to that answer.:D

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