Home>Discussions>ELECTRICAL & LIGHTING>Perplexing electrical problem
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bookwalt
Perplexing electrical problem

I have a lighting circuit issue that has me stumped. While out buying candy, my wife called me to tell me that the kids were playing with a light switch, and now all of the first floor overhead lights are out. Sounds like a tripped breaker, I figured, and took my time getting home.

Turns out it's not so simple. Here's the situation: The switches they were playing with are a 3 way next to a single pole, both controlling overhead fixtures. The lights that are out are all on one circuit, and it seems that every light on that circuit is out (including many other fixtures not on this switch). There is no voltage to the switch in question, but the breaker is not tripped. I replaced both switches first, with no luck. I swapped out the breaker with a known good one, even though the breaker was reading 120v output. I checked all the other breakers, and every one of them reads 120v.

Basically it's acting exactly like a tripped breaker, without there being one. One weird thing, I have a cheap wand-type voltage checker, and it lights up when it gets within about 8 inches of the switches, until I shut off the breaker, then it won't respond at all. Does this mean there's voltage almost to the switch, but for some reason it ends before the wires emerge from the box?

I'm stumped, but need to exhaust every option before I call an electrician. This is my first post, but I promise to stick around and be useful!

Thanks, Andy

JLMCDANIEL
Re: Perplexing electrical problem

My guess is they were flipping the switch on and off rapidly and overheated a connection in the circuit or if the switch was loose the constant movement may have cause a break in the wiring . It could be a wire nut connection that over heated and tracing the feed is the only option. I do not use wand type detectors because they often give you false readings.
Jack

djohns
Re: Perplexing electrical problem

Is there any chance that there is a GFCI ahead of the switches , possibly in another part of the house ?
Crazy I know , but stranger things have happened . :eek:

bookwalt
Re: Perplexing electrical problem

No GFCI's on this circuit, but I checked them all anyway, as unexpected GFCI issues have burned me before. It still seems weird that my voltage tester would read juice near the switch, when I can't find it with a multimeter. I don't really trust them either, but if it reads juice when the breaker is on, and none when it's off, then I can at least assume that some voltage is there. Thanks for the advice so far!

-Andy

djohns wrote:

Is there any chance that there is a GFCI ahead of the switches , possibly in another part of the house ?
Crazy I know , but stranger things have happened . :eek:

JLMCDANIEL
Re: Perplexing electrical problem

Actually the only thing you can assume with a wand is that a magnetic field is present. With something else on the circuit still receiving power you could just be picking up a field on the neutral.
Jack

sparky1
Re: Perplexing electrical problem

if you've verified you have 120 volts, with a multi-meter, not a voltage indicatior. voltager indicators are good to tell you there might be voltage present, but do not rely on them to be exact. if you have 120 volts to ground, With a meter, then check the light thats out. if the same goes for there, you lost a neutral along the line. with out actually knowing how old your house is, and seein it, its hard to tell you where to start looking for this problem. possibly other lights that are out, or switch boxes that control them, if they wire nutted the neutrals. possibly junction boxes in the basement, or attic, and check the panel connection of the neutral. hope that helps, if you dont have 120 v. check the other switch boxes for a bad connection.

Vern Smith
Re: Perplexing electrical problem

The wand only reads the "hot" wire, since the neutral is grounded at the service. If your wand lights up while near a neutral, you have an open neutral (you can hold your fingers over the end of the wand to lessen the sensitivity). If your neutral has an open circuit, you'll have to start opening up fixtures until you find the culprit. Start at the breaker panel, then try to find the first licht on the circuit and work you way to the end. I'm betting you'll find a loose connection that has overheated and finally stopped conducting.

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