I recently installed two sconces in our kitchen to replace some old halogen lights with LED bulbs. The boxes had three (?!) White wires twisted together, two black wires twisted, and one red. I surmised that the red was ground and attached the others in normal white-white black-black fashion.
Both of the lights (one of which has a gcfi outlet integrated into the switch box) trip the circuit breaker every time the switch gets flipped off.
Did I wire it wrong? Is there something I've missed?
UPDATE:
In accordance with Edwin's suggestion, I rewired the lights to cap the red wire by itself and connect the bare wire to the grounding screw in the back.
Good news: It no longer trips the breaker!
Bad news: It also no longer turns off!
I'm guessing that the bare wire I saw attached at the back isn't actually a grounding wire, and that there ISN'T one for the box…
The fixture's wire is already attached to the grounding screw on the mounting bracket. Is this sufficient, and can I just snip the rest of the bare wire after the grounding screw (rather than unscrewing everything for a third time…)?
Best Answer
Yes, you wired it wrong. :)
The red wire is another hot leg. This is a common installation when the electrician is providing wires for a ceiling fan with lights (to be independently switched). The red wire shares a common neutral with the black wire, hence the three white wires. You should keep the white wires connected. Disconnect the red wire and cap it off. There should also be a bare copper or green wire in there (maybe screwed to the back of the box if the box is metal). This wire is your ground.
Update:
As @Isaac Kotlicky pointed out, the red wire could be the switched wire. But your switch could also be miswired. Take a look at the switch to see what colored wires are going into and out of the switch. A picture would not hurt.
As far as your safety ground is concerned, you really should have a bare copper or green wire in the box. If not, it's possible that the gfci switch is making up for the weakness of having no ground wire. Make sure you test the GFCI device once you get this together and working. Another possibility is that you have metal conduit leading to the box, and it is grounded. In either case, you could simply attach the fixture ground to the metal box.