Home>Discussions>ELECTRICAL & LIGHTING>Need Help! Unmarked wires- half my house is off!
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fittobefried
Need Help! Unmarked wires- half my house is off!

I have an old house 1920's. At some point it was upgraded to a wire that looks like BX or MC. Problem is the wire are all black with some kind of fraying old fabric on them. I have pictures I happened to take beforehand and after the incident- b/c I was going to home dept and wanted to try and explain what I needed.

Here's the deal. I gave up installing a ceiling fan last year.
I am trying to install just a light now. Today I decided to work on it, and in all the wrestling/pulling/feeding with the darn things, pulled the "marking" tape right off the wires.

I have 2 cables coming in to the hole. One has 2 wires, one has 3. When I started today: 1 wire from the longer cable was attached to 1 wire from the shorter cable. The other wire from the long cable was attached to 2 remaining wires from the shorter cable.

I managed to put clamps on the cables, feed them thru the new round metal box I installed- and everything is good to go- except knowing what wires are which.

I am thinking it might be at the end of the circut? or the beginning?? When I left all wires disconnected, nothing else is coming back on on that circut.

When I test with my simple tester- I get one definate hot line on the long cable (that has 2 wires). It lights up bright on every line it touches- except one wire on the other short cable (that has 3 wires)- it glows only dimly.

I guess my problem is I don't know how to use my tester properly? It has a black and a red lead- and lights up- that's it.

Is there any way to do this besides acknowledge defeat and call the electrician?

Thanks,
Courtney

fittobefried
Re: Need Help! Unmarked wires- half my house is off!

Fyi- in the last picture- when I said "When I test with my simple tester- I get one definate hot line on the long cable (that has 2 wires). It lights up bright on every line it touches- except one wire on the other short cable (that has 3 wires)- it glows only dimly."

The bright hot wire is at 2-o-clock. The one that is dim when tested with it is at 4-o-clock.

I don't know if it makes a hill of beans difference?

fittobefried
Re: Need Help! Unmarked wires- half my house is off!

more info- when I test the rest of the wires, I get nothing. In the last picture: only the wire at 2-o-clock lights. When I touch it to every wire its bright- except that 4-o-clock wire on the other cable.

Can it be that easy?

Are those 2 supposed to go together?

How can I test it?

I would assume if I turn the power back off, twist them together, and turn the power back on, it will either complete the circut, or it wont?

fittobefried
Re: Need Help! Unmarked wires- half my house is off!

I tried the hot wire and the dim light together- didn't complete the circut- might have been the ground?

Marked that wire and tried the next of 2 wires left on the second cable and got it- the circut came back on.

I hate how old houses were run on like, 2 circuits. Our theory is the older prior occupant of our house didn't run the can opener and the hair dryer at the same time! We had to get a 220 panel when we bought the house- but left the old circuits as they were. All I know is if I ever build a house- each room (or maybe 2 rooms) has a seperate circuit!

Will try and hook up the light fixture next weekend :)

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