Just inspected 1958 ranch with FPE panel - Yes , even the client knew that was not good. Oddly though , all the outlet covers in all 3 bedrooms were old metal type and my sniffer was lighting up instantly when I touched all the covers , I couldn’t even test the outlet itself since it was going off so much. Never had this before, I touched cover plates with hand got no shock - whew . Why would all the cover plates read so strongly via the sniffer. No BX cable seen either , old style 2 prong outlets - no grounds.
The only sure way to know is with a proper voltage tester .
I expect you where just reading induced voltage a sniffer can read every thing.
What did you find wrong with the FP panel???
With the metal plate not grounded you were likely reading a phantom/induced voltage.
BTW-Not all sniffers are created equal.
Some of the non-contact voltage sniffers can be very sensitive. Try putting your finger near the tip of the sniffer without making contact with the item you are testing. You will see a great number of these false positives go away
Thanx for quick response. I figured it was something i was doing or the sensitivity of sniffer and not truly a hot plate but i want to let client know with more surety As for FPE panel. No main breaker with 8 throws and attached to garage studs by a nail through side of panel. I didnt even open it up since the breakers in ON positions always trip taking that stupid cover off. Client was expecting to upgrade service anyway so he didnt care much
I use a $20 Klein Tools sniffer with two ranges of sensitivity: 12-48v and 48-1000.
Haven’t had a “false alarm” yet…
http://www.kleintools.com/catalog/electrical-testers/dual-range-non-contact-voltage-tester