Help, think I blew out my circuit breaker trying to replace light fixture

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  #1  
Old 01-09-06, 07:23 AM
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Help, think I blew out my circuit breaker trying to replace light fixture

I was trying to replace a celing light fixture; did not realize I should have noted previous light arrangement. The light is connected to two different light switches, one at bottom and one at top of stairs. There is three sets of wires; I remember thinking it was odd that the three white wires were together and not being used. I tried all different ways of hooking up the light fixture; but now, after clicking on the breaker and it cutting off; I capped off all the wires, but have lost power to one bedroom, one that is connected to circuit of hall light. Did I blow out the circuit breaker to that room?
 
  #2  
Old 01-09-06, 09:33 AM
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You need to tell us ALL the wires in the box. Tell us any that you know were connected together before you disconnected them all.
A light fixture has two wires + ground sometimes. Those are the only wires you need to be concerned about when you change a fixture. Everything else leave alone.
 
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Old 01-09-06, 01:08 PM
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contents of electrical box in ceiling.

Thanks for your response. There are three sets of wires coming out of three seperate holes; each set consists of a black and white wire. There is also a grounding wire which is no possible to put out. When I took down the old light fixture it appears that the three white wires were capped together. The old lamp had two wires both black, but one was ridged so I assuming that is the white wire. There are three black wires, two of which look like they have some sort of white spotty coating on them. One definitive black wire. My new light fixture has two bulbs, each has a set of white and black wires. I now have the three white wires capped together and each individual black wire capped off.
 
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Old 01-09-06, 03:16 PM
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The white spotty stuff is probably just drywall compound or paint which found its way onto the wires during construction.

If you didn't note how the old fixture was connected, your project became a hundredfold more difficult than it had to be. You are now in for a lot of investigation, as there are many different possibilities.

Most likely is that one wire is the power feed, one wire is the switch loop, and one wire carries downstream power. To confirm, you will need to completely analyze the wiring at both switches, and you will need some kind of electrical test instrument. For now, a simple $2 neon circuit tester will do.

Post back when you have the circuit tester.
 
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Old 01-11-06, 01:11 PM
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I have the circuit tester. What do I do next? Thanks for all this.
 
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Old 01-11-06, 01:18 PM
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Originally Posted by joed
You need to tell us ALL the wires in the box. Tell us any that you know were connected together before you disconnected them all.
A light fixture has two wires + ground sometimes. Those are the only wires you need to be concerned about when you change a fixture. Everything else leave alone.
And tell us and wires that are hot to ground.
 
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Old 01-11-06, 02:15 PM
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You have three cables, each with a black wire, a white wire, and a grounding wire. You also have a grounding wire.

Start by shutting off the breaker. Use your tester to test all wires against each other and against ground so that you'll know whether it's safe to test them.

Then separate all the wires in the box, so that no wires are touching each other or the box.

Now number these three cables for reference (cable1, cable2, and cable3).

Now turn the breaker back on, and use your tester to make six tests:
  1. cable1 black to ground.
  2. cable1 white to ground.
  3. cable2 black to ground.
  4. cable2 white to ground.
  5. cable3 black to ground.
  6. cable3 white to ground.
Shut off the breaker again and report your results.
 
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Old 01-14-06, 08:41 AM
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Red face tested all six cables

Finally got a chance to test the cables, needed to wait for daylight. Anyway, I labeled all as you said and the only one that was hot was black cable number 3. Where do I do from here?

Fran
 
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Old 01-14-06, 08:54 AM
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Okay. Make sure that both switches are off and stay off during this test.
  • Shut off the breaker.
  • Connect the black of cable 3 to the black of cable 2.
  • Connect the white of cable 3 to the white of cable 2.
  • Leave the wires from cable 1 unconnected and separated.
  • Turn the breaker back on.
  • Stand there at the panel for a minute to make sure the breaker does not immediately trip back off.
  • Go see if you now have power in that one bedroom where you lost it.
  • Shut the breaker back off.
  • Report back.
 
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Old 01-14-06, 11:26 AM
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no power

John, did what you said connected black 3 & 2 and white 3& 2. Still no power to the bedroom.
 
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Old 01-14-06, 12:01 PM
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Power On In The Bedroom

Tried cables 3 connected to cables 1 and now have power in the bedroom. Yay! Now what do I do with the light in the hallway. What is the configuration for that?
 
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Old 01-14-06, 06:31 PM
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Good. You already guessed what I was going to say next.

So here's what you have:
  • Cable 3 is the power cable.
  • Cable 1 is power out.
  • Cable 2 is (presumably) the switch loop.
So make these connections:
  1. Cable 3 black to cable 1 black to cable 2 white (yep, black to black to white).
  2. Cable 3 white to cable 1 white to fixture white.
  3. Cable 2 black to fixture black.
  4. All grounding wires together.
 
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Old 01-15-06, 10:24 AM
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nothing happened

John, made all the connections and when I tried the light switches, nothing happened no lights came on? There is still power in the bedroom, so I didn't mess that up. There are two black wires and two white wires on fixture and I connected all same colors together. Could that be a mistake?
 
  #14  
Old 01-15-06, 12:12 PM
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Flipping the switch does not trip the breaker, does it?

Double-check the connections. Something doesn't add up here. This should have worked. If it still doesn't work after you verify everything, then we'll need to inspect the wiring at the switch boxes to see what's going on. You so far haven't touched any of the switch wiring, right?

There are two black wires and two white wires on fixture and I connected all same colors together. Could that be a mistake?
No, that is correct. I assume you mean that you connected both fixture black wires to the Cable 2 black wire, and both fixture white wires to the Cable 3 and Cable 1 white wires. Is this correct? Double-check.
 
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Old 01-16-06, 09:51 AM
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It Finally Worked

John, I went back and redid the connections and this time it work. Hallaluah! I did not have it connected tightly enough. Man, this is has been one hell of a trip to change one light fixture. You and this site are wonderful. Without your patience and knowledge I would have to call an electrician, for a price I cannot pay right now. So thank you, thank you!

Can I ask you now about attaching the fixture to the ceiling bracket, which appear might take a long as the electrical problem to fix. It has two screws that are supposed to go through fixture to keyhole slots in bracket. I'll be damned if I can get it to do this, it is impossible to see where it goes. There is all this insulation on top of fixture, does that need to stay or can I get rid of it; it really impedes seeing what I am doing?
 
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Old 01-16-06, 10:51 AM
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Do not get rid of the insulation. It keeps the fixture from melting the wires in the ceiling.

Why not just leave the fixture hanging by its wires and enjoy the light?

Sorry, I can't quite see the problem you're dealing with, but I'm sure you'll get it figured out if you keep fiddling with it.
 
 

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