ECN Forum Forums General Topics of the Trade General Discussion Area voltage present when power is turned off???

out on a job once i remember sticking my meter to check for voltage and all i was reading was 6.6v between ungrounded conductor(hot) and the grounded conductor (neutral) on the receptacle with the breaker feeding the circuit turned off.. where was this mysterious voltage coming from??? could it have been a backfeed of some sort???

smokey;
it's probably induction, you could flip breakers until the culprit was found.

thanks sparky

I still carry my old solenoid Wiggy with me, as well as my digital tester. The Wiggy puts enough load on the wire being tested to zero out these induced readings (try them both at once = 0). You can get some pretty high readings w/ the digital on long homeruns @ 277/480.

Sans Wiggy, I have put a resistor (light bulb on a pig tail) between the same two points and then measure the voltage. The connection to ground tends to "bond" any stray voltage...I think. If it reads 0 volts set up this way, then no worries...if the bulb burns, you have a short. I'm sure the wattage of the bulb comes into play here too for any resisted shorts that would complicate the issue.

I'm asking opinions here rather than suggesting this method. It's sort of a "poor man's" troubleshooting trick, but I'd like to know all the "druthers" involved... Any comments?

Look for the report at www.nema.org

[This message has been edited by Joe Tedesco (edited 01-09-2003).]