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Electrical Wiring

Troubleshooting 3-way light switch wiring

8 years ago

I'm replacing a set of 3-way light switches with motion sensor activated light switches that control 2 sets of lights. Base on the product instructions, I need to locate my Line Hot. So, I shut the breaker off and I took off the existing switches and separated all the wires from both switches. Then I turned the power back on and used a voltage tester to find the Hot line (which should have been 1 of the six - not including the ground wires). But there were actually 5 lines that were "hot". So, now I'm completely stumped on how I can locate the real Hot line? Any advice would be appreciated!

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Comments (2)

randy427
8 years ago
What type of voltage tester were you using? Digital and non-contact testers can give false positives. A cheap circuit tester, the type with two leads and a small bulb, might work better for you.

You'll usually find the incoming power to be a 2-conductor cable.
ivan1818
Original Author
8 years ago
I am using a non-contact voltage detector. I'll try to use a regular voltage tester.

I think my 3-way setup is likely power is coming from the light source rather than from one of the switches.
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