1

I have three porcelain lamp-holders that I want to install in my apartment.

Home Depot porcelain lamp-holders

I installed one without a problem in my den area, and it works with the light switch. I connected black to a brass screw, and white to a silver screw. I left the ground in the ceiling, as there was no place for it on the lamp-holder.

Measuring the hole in the ceiling enter image description here

My problem is with the bedroom

which has the following wiring setup: enter image description here

I have tried to do the same as the den, connecting 1x black wire to a brass screw, and 1x white wire to a silver screw. I left the other black wire capped, and left the red alone. The problem is, the light stays on all the time - regardless of the light switch position. I have tried both an LED bulb, and an incandescent bulb. Both stay on constantly. I have tried stripping the red wire and using it in place of the black wire, and the light did not turn on. There are no other switches that control this light.

All wires are capped back to their original states (as depicted in the photo).

Why does my light stay on constantly?

  • 2
    If you have a voltmeter, you should check the voltage between the various wires with respect to ground, with the light switch on and off. What does it show? – justin Feb 21 '17 at 0:22
  • Sounds like you picked a hot black not a switched wire a non contact tester or a volt meter can help find the correct wires. Were these boxes covered before? It is possible there is not a switched leg in that box. Can't tell on my phone. – Ed Beal Feb 21 '17 at 3:21
  • @Ed Beal yes, the boxes were covered with a plastic cap. Could using the other hot black wire make a difference? There are two twisted together in the orange cap. I think each time I tested it, I was using the same black wire. I don't think I ever tried the other one it was twisted to. – Lil' Bits Feb 21 '17 at 4:09
  • 1
    For hot and switched-hot wires, colors are not that meaningful, because they are decided by what colors of wire are in the cable. However, when the colors are available, people often like to use black for always-hot and red for switched-hot. – Harper Feb 21 '17 at 17:23
5

What you are seeing there is the light end of a new-style switch loop. The two blacks should stay nutted together (one's the incoming hot and the other goes out to the switch), and your light fixture should be wired red-to-brass and white-to-silver. The reason it didn't work when you tried the red wire the first time is likely because you didn't nut the black wires back together, so there was no power to the switch. As to why it stayed on all the time initially -- the black wire you chose the first time around was the hot feed coming in, so you wired the switch out of the circuit, rendering it useless.

  • Sounds good! I'll try it when I get home tonight, and if you are correct I will accept this as the answer. – Lil' Bits Feb 21 '17 at 14:21
  • This was it. I tried leaving the black wires nutted, and using red to brass, white to silver. It works now! – Lil' Bits Feb 22 '17 at 3:55

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.