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john mclane
07-07-2007, 9:49 AM
I have an older light fixture pair in a bathroom and while painting the bathroom wanted to replace the older light fixtures. When removing the older light fixtures, the wires got separated and I am trying to reconstruct the correct connections. This is a switched middle run light fixture on a wall. There are 4 sets of cables entering the box:
A. older cloth cord with 3 wires and white and black pigtails,
B. 3 wire Romex not live with 1 black wire with white paintdot believed to be attached to previous light fixture,
C. 3 wire Romex that goes to another rooms circuit;
D. 2 wire Romex that is hot when tested with voltage tester between black and white wire.
I'm not sure which wire is coming from switch.
I can get power to the second light fixture which was never on the switch. (I think it may the first in the line coming from the panel)

I have tried several combinations but can't seem to get the right one to get "switched" power to the fixture. I'm not adding any new lines to this circuit.

I need to know which wires to connect together and which to add to fixture? How do I tell which ones are coming from switch.

I hate to have to get an electrician in to fix this one light fixture

James Rambo
07-07-2007, 5:53 PM
When you say 3 wire romex do you mean black, white, red or black,white, bare? second light has only one 3 wire cable?

Randy Denby
07-07-2007, 9:52 PM
John, do you have access to an Ohm meter? If so, this would be the easiest way to find the switch leg. As you know the power feed line,then this will solve 2 of the 4 lines....the other 2 are probably the feed to the other light and possibly a feed to a plug. Its gonna be tough trying to help you without actually being there. Might need to have an electrician on this one. Sorry !

Just for a FYI, power cable entering the box, black goes to black on the switch leg line and white goes to ground leg on the light fixture...power comes back from the switch thru the white wire and ties to the positive/line side of the light. I always mark that white wire with a black piece of tape to keep the confusion down and to signal its the line side .

Peter Stahl
07-08-2007, 7:40 AM
I have an older light fixture pair in a bathroom and while painting the bathroom wanted to replace the older light fixtures. When removing the older light fixtures, the wires got separated and I am trying to reconstruct the correct connections. This is a switched middle run light fixture on a wall. There are 4 sets of cables entering the box:
A. older cloth cord with 3 wires and white and black pigtails,
B. 3 wire Romex not live with 1 black wire with white paintdot believed to be attached to previous light fixture,
C. 3 wire Romex that goes to another rooms circuit;
D. 2 wire Romex that is hot when tested with voltage tester between black and white wire.
I'm not sure which wire is coming from switch.
I can get power to the second light fixture which was never on the switch. (I think it may the first in the line coming from the panel)

I have tried several combinations but can't seem to get the right one to get "switched" power to the fixture. I'm not adding any new lines to this circuit.

I need to know which wires to connect together and which to add to fixture? How do I tell which ones are coming from switch.

I hate to have to get an electrician in to fix this one light fixture


John

Sounds like you need a OHM/Volt meter. I've had 3 houses and each has wired light fixtures differently. You need the power off and then keep all the wires separated. Now turn the power on and check each pair to see which has power to them, looks like this electrician brought the power to the light box, some go to the switch box. After you find the ones with the power, turn the power off and use the OHM meter to determine which wires go to the switch. Is there only one switch for this light? If there are 2 switches that operate this light then that's why there are 2 set of 3 wire romex. The electrician that did this could be using this for a light box & junction box. One wire could be a switch loop to the switch to operate the light and the other wire a continuation of the circuit. A picture and more info would be helpful. Couple questions on the following. My brother has a old house and I know how screwy wiring can get. Any time you take anything apart like this either make a sketch or mark with tape.

There are 4 sets of cables entering the box:
A. older cloth cord with 3 wires and white and black pigtails,
Are the 3 wires a Black, White and a ground?

B. 3 wire Romex not live with 1 black wire with white paintdot believed to be attached to previous light fixture,
Does this wire contain a Black, White and Ground?

C. 3 wire Romex that goes to another rooms circuit;
Does this wire contain a Black, White and Ground?

D. 2 wire Romex that is hot when tested with voltage tester between black and white wire.
Is there a bare ground wire on this wire?

James Rambo
07-08-2007, 1:48 PM
Randy Since I have been an electrician (26 years) the white wire is not to be used as a switching wire even if reidentified with black tape.national electric code says: to be used as a supply to a switch but not as a return conductor from the switch to the switched outlet. So IMHO if the circuit is being reconnected it should be done in a fashion that is up to date. I have been ZAPPED by this in the past. I usually use a tester now. but, please do it the right way.

Peter Stahl
07-09-2007, 5:54 PM
Randy Since I have been an electrician (26 years) the white wire is not to be used as a switching wire even if reidentified with black tape.national electric code says: to be used as a supply to a switch but not as a return conductor from the switch to the switched outlet. So IMHO if the circuit is being reconnected it should be done in a fashion that is up to date. I have been ZAPPED by this in the past. I usually use a tester now. but, please do it the right way.

James,

I'm not a electrician but most people won't tear their walls apart to get rid of a switch loop. My first 2 houses had them but the house I'm in now doesn't. If you saw my brothers house you wouldn't know what was what. It has about 75 years of different wiring in it. Most of the knob/tube is gone but some of that cloth like covered 12/2 wire is still there. I do have a question, is there a legal/code way to do a switch loop?

Cliff Rohrabacher
07-09-2007, 6:01 PM
I use a very high tech method.

With the power on touch each wire to the grounded metal box. They one that provides a moment of excitement is the hot lead~!!

Woo hoo

Use insulated dykes to hold the wires.

This has the added benefit of showing you which breaker it's connected to also.

Told you it was high tech.