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Posted By: dzmacdvm Polarization help - 10/24/01 12:25 AM
I recently installed a new circuit. The wiring runs to a 2 gang box with 2 switches where the hot wire is shared via pigtail. One of the switches runs to 3 consecutive fixtures (recessed lights) and the run ends in a receptacle (outlet). When I connect the black wire to the brass screws and the white lead to the silver screws and the ground to the ground screw and test this outlet, the polarization detector indicates that the hot and neutral wires are opposite. The light indicator shows correct polarization when/if I connect the black lead to the silver side and vice versa which I know should be wrong. Is the problem at the level of the switch where the hotwire is shared? Or how else could these 2 be opposite? Any suggestions greatly appreciated. Thank you.
Posted By: spkjpr Re: Polarization help - 10/24/01 01:43 AM
What does the second switch control? I also seem to remember an articlle about neon tpolarity testers being fooled if the circuit has any other neutral connections. Will try to find the article, believe it came from ECM Magazine.
Posted By: dzmacdvm Re: Polarization help - 10/24/01 02:32 AM
The second switch also controls recessed lights but on a dimmer. Put on 2 switches because didn't want all on dimmer and dimmer switch cant handle the load of all of them. So youre saying that though I have it wired correctly, the detector might not be accurate in this instance? The tester I'm using is a 3 prong with 3 light indicator, not very sophisticated.
Posted By: Redsy Re: Polarization help - 10/24/01 02:37 AM
Where did you pick up power for this new circuit?
Posted By: dzmacdvm Re: Polarization help - 10/24/01 03:39 AM
Added a 15Amp breaker at panel specifically for this lighting project.
Posted By: amp-man Re: Polarization help - 10/24/01 03:57 AM
DZ,

I suspect that you've flipped the hot & neutral at one of the light fixtures.

In telco parlance, a "crossed pair".

Remove the lamps in the three fixtures and get yourself a good grounding conductor reference (like the ground pin of an extention cord plugged into an outlet that tests out good; or the metal housing of the can light, if that's what you're dealing with). With the circuit off, starting at the fixture first in line from the switch, check continuity between known ground and the lampholder shell. The fixture where you lose continuity is the mis-wired one. The shell should be connected to the grounded conductor...with H and N flipped, the shell would be hot & the button neutral. The dumb lamp doesn't know any better, it'll still work...

You could test the circuit hot using a test light or voltmeter, but it's safer testing it cold, using a continuity buzzer.

Work safe,

Cliff
Posted By: dzmacdvm Re: Polarization help - 10/24/01 04:58 AM
Thanks Cliff, will give it a test. I appreciate your time.
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