can light wiring problem

Old 04-05-14, 02:57 PM
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can light wiring problem

I went to put a retrofit LED light in my can light. But after completing it the light does not work. I even put it all back the way it was and still nothing. Double checked the bulb and it works fine. When testing to see if I had power I touch the tester to the black line going into to bulb screw socket and when I touch the other probe to the metal can housing itself I get a power reading. I get nothing when touching the black wire and white wire. Seems something is wrong to me and that the metal housing should not be hot or am I wrong?
Old 04-05-14, 03:16 PM
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Metal can is not hot, it is grounded. It is correct to see ~120 volts between the ungrounded conductor (black) and ground but you should also see ~120v between the ungrounded conductor (black) and the grounded conductor (white/neutral). You don't so you have an open neutral. You need to start checking connections. It likely is in the last working can light or first non working. Don't just look redo the connections.
Old 04-05-14, 03:16 PM
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Welcome to the forums.

Neutral and ground are at the same potential. They connect to the same place in the panel. The ground wire is only used as a safety line in case of shorting to the can.

So.... you WILL measure 120v from the black to the ground. You should also measure
120vac from black to neutral..... since you don't...... you have an open neutral. If the can that this one connects to is working..... then the open is in that can or the one you are working on.
Old 04-05-14, 03:17 PM
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Putting your probes between Black and Ground (metal can) should give you a full voltage reading.

Black to white should also give a full reading, in most cases, as white is neutral, and neutral is connected to ground back at the panel (or, at least, it should be).

Edit: sorry, Nash is correct. You've got a loose neutral somewhere.

Last edited by Seattle2k; 04-05-14 at 03:33 PM.
Old 04-05-14, 03:19 PM
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Welcome to the forums!

Seems something is wrong to me and that the metal housing should not be hot or am I wrong?
Yes. The housing isn't "hot." The ungrounded potential, or "hot power," is on the black wire. The housing is connected to ground, as it should be.

The fixture isn't working because the grounded conductor - the white wire - is disconnected somewhere. Turn the power off at the breaker and look for that. It's probably in this fixture, since that's where you were working, but may be in the next one upstream.

Id this fixture the only one on this switch, or are there others? If so, where is this one in the set?

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