How do you find the hot wire on a light switch?
In a properly wired switch, you should find a bare ground wire
of copper. Using a DVM or voltmeter, measure the voltage between
the ground wire and both wires attached to the switch. One should
be hot or at 120 volts. The other wire will lead to the device the
switch turns on or off. If there is no ground wire, you can run a
temporary wire from a earth or pipe ground to get a