I have a single toggle switch that is used to turn on/off outside lights. When the switch is in the OFF position I get a voltage reading of 72.5. across the terminals. When the switch is in the ON position, I get 0 volts across the terminals.The hot input is a white wire, and the output wire is black. I get a 120 V reading betwee the white wire and ground. Do I have a bad switch? In the ON position it lights up the outside lights; in the OFF position they are turned off.
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Replies
The 72V reading is a bit odd -- I'd expect 120V if the bulb is screwed in, and only an odd voltage like 72V if you had a 3-way switch setup. But voltmeters do strange things in household electrical circuits, and everything else sounds normal.
What leads you to be poking about there to begin with?
When the switch is off, the current is trying to travel through the volt meter. But there's some resistance in the light bulb(s) in the circuit. That's why you don't see the full voltage.
If you check from the hot side of the switch to ground you should get the full 210 volts. (+/-)