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While renovating my mother's family room, I need to remove the light fixtures. So I flipped the breaker. The lights went off. I was about to remove and luckily double checked for voltage. I found it was still live. Went back to the breaker switched it on and all the lights came back on. Does anyone have an idea what's wrong with my breaker or is it just a bum current detector?

isherwood
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brady Van der Spank
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    What are you using to test for the presence of electricity? Are there other circuits running through the box for the light fixture in question? – ThreePhaseEel Feb 14 '21 at 20:35
  • I used a non contact voltage tester. The circuit has several lights on the same switch. – brady Van der Spank Feb 14 '21 at 23:54
  • Ah yes, as others here have called them, the "magic 8-ball detector" which are notorious for giving false readings due to voltages induced by nearby cables. Yet 3phEel makes a good point, there may be more than one circuit there. Not likely, but possible. The fact that the lights went out when you turned off the breaker tells us that the breaker is operating properly, but again, it's remotely possible there is more than one circuit there. Can you post a picture of the fixture box BEFORE you take anything apart? – George Anderson Feb 15 '21 at 00:00
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    Yes, can you get us photos of the inside of the fixture box please? – ThreePhaseEel Feb 15 '21 at 00:43
  • Use a volt meter to measure to ensure the power is off – FreeMan Feb 15 '21 at 18:14
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    Does this answer your question? [Unexpected voltage with switch turned off](https://diy.stackexchange.com/questions/110092/unexpected-voltage-with-switch-turned-off) – FreeMan Feb 15 '21 at 19:20

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What you are seeing is called phantom voltage. This is a voltage induced from another live circuit that is running parallel to your now dead circuit.

Proof the breaker worked all the lights went out.

Phantom voltage is a voltage and depending on several factors it may be 120v but there is no current potential thus the lights are out.

There is a possibility that this could be part of a multiwire branch circuit And the neutral is conducting the other circuits power back to the source. And that’s why multiwire branch circuits require handle ties by modern code.

Ed Beal
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