quick wiring question

[hguerrero]

trying to hook up a light fixture to the ceiling....

sounds simple enough...ground, white, and black coming from the ceiling...

however, the fixture has a ground wire plus two same color wires...

how do i know what's the positive and what's the negative at the fixture?????

 

[Joe92GT]

Ac doesn't have positive and negative. Only line, and neutral. If the fixture has no markings on either wire, it does not matter. The only reason a fixture would have a polarity would be to help prevent the chassis from being energized by the non-grounded conductor. Electronically it makes no difference which wire is which on the fixture side.

The ungrounded connector (hot) is always kept as black to be identifiable for many reasons on the house wiring side, most of which are safety.

 

[hguerrero]

thanks joe! i'll try it....stand by with 911 !

 

[Identaltech]

dose one of the wires have a ridge running down it?
if not just use a volt meter set it on ohms
one lead to the screw part where bulb screws in and with the other lead find the wire with no resistance that will be your neutral

 

[Joe92GT]

Yes, if your that worried about it, Identaltech is correct.

 

[Tech Guy]

You always want the bottom of the socket to be live (where the bottom of the bulb connects to socket. The body of the socket is to be neutral (threaded part of bulb) so you dont accidently shock yourself.

 

[sberry]

He is likely dealing with a switch loop???????

 

[kbs2244]

This doesn’t sound like a factory wiring job on the fixture.
Has someone been there before you?
As was said an incandescent bulb won't care, but the hot should be the center tab and the shell the neutral.
A florescent ballast does care which is which.
You have to check the wiring diagram on the ballast and be sure to get it right.

 

[nate379]

True on flourecents. I didn't know that and wired up a whole shop backward. Guess what... none of the lights worked

 

[hguerrero]

hooked it up by joe's advice and it worked...still waiting for the house to burn down...but the light works!

thanks guys