how do i power a added outlet box from an existing light fixture

re: electrical	wirenuts	7:42 pm saturday september 22, 2001

first you make sure the light fixture is fed, and not the switch. This will ensure a constant source. Then you make sure the colors (white, black..) are what they really are, then you make sure it has a viable grounding ( usually bare ) conductor.

re: electrical	Warren Goodrich	3:14 pm sunday september 23, 2001

Wirenuts is right. Often times the power is brought to the switch then a switch leg only is ran to the light fixture. If this is your wiring design then you would only have power at the light fixture when the light switch is on.

Take a voltage tester and shut off the light switch and see if you have power in the light fixture with that light switch off.

If you have trouble understanding what wire is what then come back in and tell us how many cables enter your light box and what color of wires are wire nutted and what color of wires from what cable is connected to the light fixture wires. Then we may be able to get down and dirty as to proper connections to add a recepatcle.

Also as Wirenuts advised make sure you have and equipment grounding conductor in that light box. That wire will be green or bare coming from the power source. If you do not have a green or bare conductor then you will either have to run an equipment grounding conductor from the panel to that box or not add a receptacle to it as per NEC requirements.

Hope this helps

Wg

re: electrical	Don Kerr	12:54 pm monday september 24, 2001

I will assume that you want the outlet that you want to add to be in an always on state. Therefore you can only do this if you have a neutral and an unswitched hot at the fixture. You will always have a source of neutral at the fixture.

If the source is at the fixture then you will have an unswitched hot at the fixture, if the source of power is at the switch you may not have a source of unswitched hot at the fixture.

If you look at the fixture and see how many electrical cables are entering the fixtures box. Each cable will have a black/white/bare wire. If only 1 cable is entering that box and both white and black wires are going to the fixture then there is NO source of unswitched hot at the fixture box.

If there is more than 1 cable entering the fixture box , then you could have an unswitched hot at the fixture. If that is the case then check if there is one cable that has its white wire going directly to the fixture, and the black wire connected to a white wire of another cable. If that is the case then the cable with the white wire going directly to the fixture , THAT CABLE IS THE POWER SOURCE, we will call that cable 1. The other cable (cable 2) should have a black wire going directly to the fixture and the white wire connected to the black of cable 1. Cable 2 is the cable going to the switch. (cable 2 going to switch may or may not haev a piece of black tape wraped around the ends to redesignate it as a hot wire) To connect an unswitched cable onward, pigtail the new cable to cable 1, black to black , white to white and grounds together, and grounded to box (if metallic). At the outlet, black to brass color screw and white to silver colro screw, bare to box(if metallic) and to grounding screw of outlet. Leave cable 2 connected as it is now.

If there is a red wire on any of the cables ,please repost and indicate on what cable it is in and what the red wire is attached to.