weird voltage readings

[drrhoads]

I have an issue with the installation of some can lights and recpt circuits. My recpt circuit is disconnected on both ends but when I reference it to a ground in the breaker panel, I read 50vac on my dvm. When I turn off the lighting breaker the voltage goes away?? Any ideas?? thanks

 

[ibew501ed]

probably a phantom voltage due to induction.
if you connect a small load to the circuit and then measure it with a dvm you'll find the voltage goes away.

 

[mivey]

I have an issue with the installation of some can lights and recpt circuits. My recpt circuit is disconnected on both ends but when I reference it to a ground in the breaker panel, I read 50vac on my dvm. When I turn off the lighting breaker the voltage goes away?? Any ideas?? thanks

Phantom voltage. Put a load on the circuit and it should disappear.

add: I was too slow

 

[drrhoads]

I understand the induction part but, i did get a "tingle". I pulled the wire back out of the breaker panel and had it hanging in free air. I referenced a ground in the panel and read 50vac. My concern was a possible "back-feed" somehow?? Why the "tingle"??

 

[ibew501ed]

is it a 3 wire circuit, is it romex, is it concealed, I think we need mo info

 

[drrhoads]

All is 12/2 w/g Romex. All is new installation. recept circuit is in EMT conduit on the outside of the finished wall.

 

[ibew501ed]

sounds simple......but the only way to really know is with a small wattage lamp
connected to the 2 points where you get the reading. 25w bulb at 120v would yield about 5 watts at 50 v

 

[drrhoads]

But where could this stray voltage be coming from? Is it possible that back feeding could be an issue?

 

[ibew501ed]

if it a 12/2 and exposed emt how can it be a backfeed?
I still think it phantom voltage

 

[drrhoads]

501ed.....I'm with you, This should be a textbook install. The "tingle" concerned me a little but I agree with the phantom.

 

[ibew501ed]

try a bulb for a load

 

[drrhoads]

how do you mean?

 

[cadpoint]

You have a nick in the wire that's in the conduit! Probably the undgrounded wire!

Or

You have a nick or pinch in the can light branch! I"m thinking the latter, due to you OP description.

Rememeber that you should not read any voltage on a single circuit of neutral to ground! Thus your 50 volts!

Maybe I'm totally wrong to say "remember" that but I've seen a pinched wire on a circuit were I could read 50 volts on neutral to ground, shorted the wire (not by me) that then blown out the pinch point on a ungrounded circuit.

PS
The stray voltage on the neutral also smoked a majastic motion sensor that was put in without checking for this shorted or grounded circuit voltage, by me! I don't think it's phantom in this/(your) case!

 

[ibew501ed]

to test with a lamp take a pigtail socket with a 25 or 40 watt bulb and connect it the way you connected your DVM. If it glows or lights you've got a problem (see cadpoint post)

 

[zappy]

How about using a wiggy?