When installing a light fixture - if the black and white wires are not clearly marked...?

Question

.. and I connect black to white and vice versa..

it won't blow up or anything right??

(just won't work..)

?

Answer 1

when you say wires are not clearly marked do you mean from the fixture as a lot of fixtures have two black wires ....no it does not matter in this circumstance...will not cause no problems which way you connect it as both wires are isolated from frame ground...yes the light will still work

Answer 2

Be careful. The light will usually work, but it could be against code. Connecting the different colours correctly is how they make it safe for an electrician to work on your house - by following the colours, he knows if a wire is hot (electrified) or not.

Both black and red denote a hot wire - these can be connected to the black wire coming from the wall/ceiling. Return wires are pretty much always white. If the fixture is grounded, the ground wire will be either green or plain wire (no plastic cover) - This must be connected to the house's ground wire.

Failure to follow the correct connections can result in catastrophe - the light may work, but you may also electrify the outside of the fixture, or even your water pipes (for safety, these are often grounded as well.) Or you could cause an someone in the future to be electrocuted. And if your work isn't to code, and someone is injured or killed (or if the house burns down), your insurance company probably won't cover you at all.

Answer 3

my house has the old knob and tube wiring in it, any color marking has worn off, long ago. here's what i do to determine which wire is which, you will need an extension cord long enough to reach a grounded outlet, and a multi meter. to do this the electricity will need to be on, so you will need to be careful and pay close attention to what you are doing. plug the cord into the outlet and run it to the wires that you are working on, set the meter to 200 volts a/c, and insert the black probe into the ground terminal on the cord. next, touch the red terminal to one of the wires and look at the meter, if the needle jumps up to 120 volts, this is the hot(black) wire. if the needle doesn't move, this is the white wire. if neither wire causes the needle to move, either the switch is turned off, or you did not have a good connection in the cord, check and try again. now everyone uses black electrical tape on everything, so i bought a roll of red tape and a roll of white tape, i "label" the hot wire with the red tape, and the neutral wire with the white tape. as i have fixed outlets and switches in the house, i label the wires as i go. you can get these tapes at any home improvement or hardware store, and while you are there, consider a polarity tester, it just plugs into an outlet and has little lights in it to tell if the outlet is wired correctly. the meter, tester, and tape should cost no more than $30.00 or so. good luck, hope this helps.

Answer 4

Stat's right. With a light fixture all you need to do is complete the circuit. This happens with the bulb filament illuminating. It won't make a difference how connect to the terminals. If you were hooking up a ceiling fan, or any motor, polarity would come into question. You'll be fine.

Answer 5

you will most likly reverse the polarity and blow a fuse. im assuming by you saying light fixtures you are working on a house. but what you should do is look further iin to the two wires. blk with blk and wht with wht. if its too hard to find out just get a test light and test it and find your power source. and done.. but becareful dont hurt yourself doing this. 120 volts through the body is no fun.

Answer 6

Wrong. Black to black and white to white. The reason for this is so that the outer shell of the socket is neutral and the center contact is always hot.

Answer 7

Cardude, have you tried a glow tester on your K&T wiring? They cost $20 and work great finding the hot . I have tried your method, but never did again when i got the glow tester.

Answer 8

It will still work but the hot wire will be hooked to the socket shell.