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How to check Outlet wiring Black-White-Red with a multimeter

How to check Outlet wiring Black-White-Red with a multimeter

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  #1  
Old 05-27-14, 01:09 PM
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How to check Outlet wiring Black-White-Red with a multimeter

I was wondering how to check the Outlet wiring Black-White-Red with a multimeter.

There are two ceiling outlets each with 3 wires (White-Black-Red) and ground and a light fixture outlet as shown in the pictures.

Power is on and when I touch each wire with others the multimeter doesn't show any voltage.
 
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  #2  
Old 05-27-14, 01:17 PM
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When checking at the ceiling box. Try from white to red and from white to black. One combination may be switch controlled and one combination may be always live.
 
  #3  
Old 05-27-14, 07:01 PM
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I have checked from WHITE to RED. There is approx. 117 volt.
For what is the black wire? Is it hot?

To connect a ceiling fan:

1- Which one of the wires is ground wire that connects to the green ground wire from the ceiling fan?

2- The ceiling fan instruction says "white power wire and black power wire" but not red wire.

3- How to connect the ceiling fan?

Again, white and red wires from the ceiling are the one with 120 volt, NOT the black wire.

Should the unused black wire go back to the ceiling outlet?

Thanks
 

Last edited by thxbest; 05-27-14 at 07:18 PM.
  #4  
Old 05-27-14, 07:21 PM
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It's hard to see with the paint but the bare wire gets connected to the green of the fan.

Did you see if the red/white pair is switch controlled ?


There is a piece of three wire cable plus ground run to that box. They have run a switched line and an always live line for you to use.

The white is neutral..... period.
That leaves red and black. One of these is always live and one is switched.
You need to determine if it's the red or black that is switched. The other one will be always live.

(it's possible that they are both switched)
 
  #5  
Old 05-27-14, 09:27 PM
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Sounds very much like it's a 3-way circuit.
 
  #6  
Old 05-27-14, 09:45 PM
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No.... it's not a three way circuit. If you look back at the pictures you'll see the OP has pulled out a dual single pole switch. It is fed with a black wire and there is a red and black wire leaving it. We just don't know if one of those switches or both are feeding the ceiling box.
 
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