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Old 04-12-2013, 08:19 PM  
Frank0
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Default Polarity for wiring ceiling light

Hi!
I have new light fixture for ceiling and instructions say attach smooth wire to power and wire with "longitudinal ridges" to neutral. Well I see and feel no difference in the two wires, which look like speaker wire. What happens if I wire it backwards?

Thanks!



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Old 04-12-2013, 08:52 PM  
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When you unscrew a bulb there is exposed metal on the threaded part of the bulb as it unscrews. The ribbed wire (neutral) is connected that part of the socket so that if the power is on when unscrewing the bulb you will not get shocked. The power will be the button down in the bottom of the socket which is not exposed while removing the bulb.



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Old 04-12-2013, 09:09 PM  
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When you unscrew a bulb there is exposed metal on the threaded part of the bulb as it unscrews. The ribbed wire (neutral) is connected that part of the socket so that if the power is on when unscrewing the bulb you will not get shocked. The power will be the button down in the bottom of the socket which is not exposed while removing the bulb.
So if I have the power going to the ribbed section of the bulb it would not light and I'd know it was backwards? I can't believe this pos light fixture does not use colored wire or colored shielding.
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Old 04-12-2013, 10:00 PM  
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It will function either way. It is only a safety issue.

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Old 04-12-2013, 10:19 PM  
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It will function either way. It is only a safety issue.
Thanks Joe!
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Old 04-13-2013, 07:49 AM  
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Visually trace a wire to it's destination on the fixture or use a volt/ohm meter to identify a wire and hook it up correctly.

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Old 04-13-2013, 09:30 AM  
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It is more than a safety issue. I installed a multi-bulb bathroom light fixture which was manufactured backwards. When I lit the fixture, it worked for a while but then ... wait for it ... the light bulb glass fell out.

YES WAY. A crack developed around the bas of the bulb and it fell out! "HUH?" I said. So, I noticed the bulb was from China and replaced it with an American bulb. It stayed lit but the one next to it fell out. Replaced it. Then the American bulb fell out!

Sense the polarity problem, I reversed the wiring. Tossed the Chinese bulb. Re-lit the fixture. It worked fine.

True story!

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Old 04-13-2013, 11:29 PM  
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Visually trace a wire to it's destination on the fixture or use a volt/ohm meter to identify a wire and hook it up correctly.
Thanks kok, after joe's reply I came to my senses and remembered I had a meter in the garage and and checked the wires for continuity to the wrap on the inside of the light socket and the power post at the top of the socket and then wired it up.
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Old 04-13-2013, 11:30 PM  
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Quote:
Originally Posted by CallMeVilla View Post
It is more than a safety issue. I installed a multi-bulb bathroom light fixture which was manufactured backwards. When I lit the fixture, it worked for a while but then ... wait for it ... the light bulb glass fell out.

YES WAY. A crack developed around the bas of the bulb and it fell out! "HUH?" I said. So, I noticed the bulb was from China and replaced it with an American bulb. It stayed lit but the one next to it fell out. Replaced it. Then the American bulb fell out!

Sense the polarity problem, I reversed the wiring. Tossed the Chinese bulb. Re-lit the fixture. It worked fine.

True story!
I could see that happening to me.....
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Old 04-14-2013, 06:55 PM  
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Quote:
Originally Posted by CallMeVilla View Post
It is more than a safety issue. I installed a multi-bulb bathroom light fixture which was manufactured backwards. When I lit the fixture, it worked for a while but then ... wait for it ... the light bulb glass fell out.

YES WAY. A crack developed around the bas of the bulb and it fell out! "HUH?" I said. So, I noticed the bulb was from China and replaced it with an American bulb. It stayed lit but the one next to it fell out. Replaced it. Then the American bulb fell out!

Sense the polarity problem, I reversed the wiring. Tossed the Chinese bulb. Re-lit the fixture. It worked fine.

True story!
Never heard of such a thing, unless you are off grid and using battery power there is NO polarity. Alternating current is what comes from the power company, yes it changes from positive to negitive at the rate of 60 times a second (here in the US) that is where we get the term AC. We have a hot side and a neutral side and a light bulb could care less which side is which, so the safety aspect is the only thing to be concerned with.


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