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please help with switch loop...

Posted by syd81 (My Page) on
Sun, Apr 3, 11 at 20:26

Can someone clarify how to wire multiple fixtures with the switch at the end of the run (switch loop)?

This is what I have:

Power in Black to Switch White
Power in White to Fixture One White
Fixture One White to Fixture Two White
Switch Black to Fixture One Black
Fixture One Black to Fixture Two Black

This is related to my previous post concerning fluorescent fixtures.

I wired up new lights, but when I turn them on, they seem dim and buzz.

As I understand it - it should not matter that they are fluorescent fixtures.

What am I missing? What else would cause fluorescent fixtures to buzz?

Follow-Up Postings:

RE: please help with switch loop...

Hello syd81

Here is a fast drawing I made on how to wire up your
project.. You might have to bring the "white wire" into the switch box if your on the NEC 2011 regarding switch loops.
If you are, use the top drawing. If you are NOT use the bottom drawing..


Hope this helps…

let us know how you made out with your project!!

Have A Nice Day

RE: please help with switch loop...

Thanks for great diagram! I've been looking for something this precise for the better part of the day!

Looks like I have it wired properly. The only difference is that the proximity of everything lets me use 2 wire in place of the 3 wire - I have the power-in black hooked directly to the switch white.

Is there anything else that could cause the buzz?

I'm going to wire a plug to the fixtures and try them individually on a different circuit, see what I get.

RE: please help with switch loop...


Turns out you need to install all the fluorescent tubes.

These fixtures have two tubes per fixture.

I didn't realize that I could not test the fixture with just one bulb per fixture.

I'm hoping that I am in the clear now.

Thanks for all the help!

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