I have an Industrial Installation of a string of about 20 SPST Emergency Stop Switches in series, They are wired Normally Closed. 24VDC is connected to the string and the switches will interrupt the 24V when pressed in and Emergency.
The wire is 18 GA stranded and the total length of the string is about 800 feet.
The wire runs in conduit.
I believe I have an intermittent short to the conduit, usually the short occurs just momentarily so troubleshooting is difficult.
I was thinking of Hi Potting the Switch String. I was going to disconnect each end of the string and Hi Pot the cable run along with the installed E Stop Switches. To verify if some part of the conductor is very close to the conduit.
I believe the wire is rated at around 600V.
The question is what Voltage should I set the Hi Pot tester to and why. The other end of the Hi Pot tester will connect to the conduit.