I am currently trying to install a light fixture and I'm really confused, I've never seen wiring like this before and I'm not sure what goes where. There are 6 wires in total, 3 black and 3 white. 2 of the blacks and one of the whites are wrapped in tape, 2 of the whites are capped off together and one if the blacks is capped off alone. How do I tell the difference between them and which is the ground?
Wiring – 3 black wires and 3 white wires
groundinglightingwiring
Related Solutions
Warning: You'll be working with live electrical wires during this procedure. If you don't feel comfortable doing so, please contact a local licensed Electrician.
- Set up your multimeter (or voltmeter) to measure volts AC.
- Very carefully remove the caps from the white wires, making sure the wires do not come into contact with anything.
- Turn the switch to the ON position.
- Touch one probe from the meter to the bare grounding conductors.
- Touch the other probe to the exposed end of one of the "white" wires.
- Touch the probe to the other "white" wire.
You should have measured 0 volts to one "white" wire, and line voltage (~120 volts) to the other. Using a bit of black tape, or a black marker. Mark the "white" wire that measured line voltage to ground.
- Turn the breaker off, and verify power to the circuit is off.
- Connect the white fixture wire to the unmarked "white" wire from the ceiling.
- Connect the black fixture wire to the marked "white" wire from the ceiling.
Warning: You'll be working with live electrical wires during this procedure. If you don't feel comfortable doing so, please contact a local licensed Electrician.
The switch/outlet combo you have could physically work, but as pointed out by @Speedy Petey, it would not be code complaint since all outlets in bathrooms need to be GFCI. Consider replacing it with a GFCI/switch combo such as this.
The wiring you have should work. One of the cables (which consists of one black and one white wire) is from the mains, and the other cable (black and white) goes to the existing light fixture. You need to determine which is which. The easiest way to do this is with a non-contact tester.
With the power on and the old switch turned off (first make sure no bare wires or contact points are touching anything metal), check to see which black wire causes the tester to beep. If they are already disconnected, just check each wire separately. The one that beeps is the constantly hot wire from the mains. The other black wire is a switched hot going to the fixture. Turn the power off at the circuit breaker and mark the constantly hot wire with a piece of tape. Disconnect the old switch.
Look at the new switch/outlet on the right side (the side with the black screws). If there is a metal connector showing between the two black screws, you only need to attach the hot wire to one of them. If there is no connector, you need to attach the hot to both of them. This can be done by adding two short pieces of black wire (called pigtails) to the hot wire and then connecting the other end of those new wires, separately to each screw.
Now connect the other black wire from the box (the switched hot to the fixture) to the brass screw on the left side of the switch.
If there is no green or bare wire coming from the existing cables, you cannot properly ground this device unless the box is metal and the cables are armored (covered in a spiral metal casing). If there is a green or bare wire, it should be attached to the ground screw. If the box and cables are metal, the metal attachment strap of the device provides a form of ground (but not the best).
If the cable is not armored and there are no ground wires, the outlet is protected by the GFCI circuit, but it is not grounded. It needs to be marked on the outside as No equipment ground.
Images and links are for illustration only, not an endorsement of goods or sources
Related Topic
- Wiring – How to connect a new fixture to a box with two black and two white wires
- Lighting – 6 wires one light
- Wiring – 3 white wires & 3 black wires coming from ceiling box
- Wiring – 3 white wires and 1 black wire in ceiling fixture
- Electrical – Ceiling Box with 2 Black Wires and 1 White Wire Explained
- Wiring – 3 black and white wires at light
- Wiring – 2 black and 2 white wires, but one black & one white are on the same side of a switched receptacle
- Electrical – How to connect a light to box with 4 black wires, 3 white wires
Best Answer
The straight answer is the two whites together go to the white, or neutral, of the fixture. The single black goes to the black, or hot, of the fixture. Leave the other splice alone, just fold it back in the box.
None of what you describe is a ground. If there is a bare or green wire anywhere that would be your ground. Also, under some circumstances the box itself, if metal, could be a valid ground, but this depends on a few things.