On Friday, July 5, 2019 at 1:13:40 PM UTC-5, wrote:
On Fri, 5 Jul 2019 08:10:26 -0700 (PDT),
wrote:

I have a strange one Im replacing a lot of switches & outlets down stairs when I cut the power test the outlets and switches all is good however when I was trying to work the up stairs I turned the breaker off and with test plug it into all the outlets tester showed no power so pulled a cover off standard porcelain light to
replace it with a switch I test the wires again before starting both the black and white showed red but the flasher was beeping slower than when power was on I decided to check the outlets same thing there. I checked the tester again nothing I put my multimeter on no voltage when I use the power tester all wires show red or hot I
have two new testers and checked them both on it and a circuit elsewhere they are working you thing I have another circuit wire in I turned all the circuits off in the rooms around it no difference same problem in my bedroom with bother breaker

Short the hot to the ground, if no sparks, you are just seeing induced
voltages. No big thing. It is a product of the very high impedance
test equipment we are using these days.

I have a GFCI that keeps going bad. So this time I put a multimeter to the wires instead of using a voltage tester that just beeps. What I found is the hot (Black) wire from the circuit breaker panel has approximately 12 VAC on it, even when disconnected at both ends. I pulled the wire back and forth in the conduit to try to move it if it was shorted to another wire, but that made no difference. There are 2 other hot wires running through the same conduit. when I shut either one of those off the voltage drops to about 4..5 and when I shut them both off it is zero. I assume this is inductance. Short of running the wire in a separate conduit can I fix this and is it what is causing my GFCI's to fail.