unknown wires

Old 01-21-04, 09:19 PM
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Question unknown wires

I'm renovating a kitchen and replacing a light fixture--which has been flourescent. My assistant removed the fixture and separated the wiring without first noting what was attached to what. How can I find what goes to what without having to hire a $100/hour electrician? It's controlled by two three-way switches but is part of a circuit that includes outlets and switches in an adjoining room. The fixture's electrical box has four sets of black and white wires--and no red wires or black marks or tape on any of the white wires.

How can I decipher this?

Old 01-21-04, 09:40 PM
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You have a reasonable chance of tracking down the wires but you will need a voltmeter or some kind of test light that will at least indicate 120 VAC and DC continuity. A couple of test leads would be helpful as well.
Old 01-22-04, 03:32 AM
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How do I use the voltmeter and/or test light--and test leads--to do this?

Please assume that I know nothing about any of this.

Old 01-22-04, 03:49 AM
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Where are you located that an electrician gets $100 an hour?????

I may need to relocate!

Tell us exactly how many cables there are and how many of what color wires are in them.
This is the only way to start to help you.

Or I can show up for...let's say...$90 an hour.

Just to note;
You mention your assistant. Are you getting paid to renovate this kitchen? In many areas it is illegal to do this electrical work if you are not an electrician and are getting paid. There are some serious liability issues here. Especially if you or your helper have no clue about electric.
Old 01-22-04, 05:12 AM
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It would also help us to know some details about how they were connected. For example, all of the white wires were wired together, or there was a white wire connected to a black wire. Even if you don't know specifics, tell us what as much as possible.

And by the way, I am not going to assume you know nothing, but rather I am going to assume that you have learned a valuable lesson about taking detailed notes about how existing wiring is connected before proceeding with removing outlets or fixtures.
Old 01-22-04, 06:44 AM
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Start by finding the power cable. Use your voltmeter or circuit tester (with the power on) to test each of the four black/white pairs. Only one of the four should register voltage. That is the power cable. Mark it and then post back for the next step (which will be to identify which of the remaining three cables is the switch loop).
Old 01-22-04, 09:05 AM
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I conclude from you description that there are 4 2-wire cables in the C-O-B. This suggests that one of the 2-wire cables is a "switch-loop". Please know that if you connect the 2 wires of the S-L across the 2 wires of the "Feed-In" cable, you will have a "dead short" if the S-L is "Closed"

You can identify the 2-wire S-L cable by a simple continuity test using a multi-meter. Before initiating this test, you must be absolutely certain that there is Zero volts across ALL Black and White cable-pairs, and Zero volts between ALL Black wires and ALL White wires and Ground.

Hint; do not install the fixture until you have connected a test-lamp socket to the "final" connections. Connect the fixture ONLY after the test-lamp indicates correct switch-control.

Good Luck & Enjoy the Experience!!!!!!!!!!!!

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