light switch with 4 wires from same wire bundle

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Old 02-29-20, 04:05 PM
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light switch with 4 wires from same wire bundle

I have an old light switch which has 4 wires connecting to it,

the wires are in color of red(hot), black, white, bare.

I was thinking the red is hot, black is load, white is neutral, bare is ground, but the light won't come on after the installation, i changed to another new switch, same thing. The light won't turn on.

I removed the switch and notice all 4 wires come from one same wire bundle.

What did I do wrong?
 
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Old 02-29-20, 04:22 PM
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all 4 wires come from one same wire bundle.
Normally the ground is not counted in the wiring count. So you have a three wire cable w/ground.

That is a dead end three way switch location. One of those three wires was on a dark/black colored screw terminal. That dark screw is the common location on the switch. That same wire must go back on the dark screw of a new three way switch. The other two colors can go on either way.
 
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Old 02-29-20, 04:32 PM
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Thanks PJmax, much appreciated!

I did not take note when I removed the old switch this time so I cannot remember which is which, but I guess the red(hot) is the common, and the white is not neutral correct?

Googling 3 way switch now.
 
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Old 02-29-20, 04:48 PM
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If the white was connected to the switch, then no, it is not a neutral. You should mark it as a hot wire with black tape.

 
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Old 02-29-20, 04:54 PM
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The white was connected to one of the screws.

the old switch has two brass screw, one black screw(common), and a ground screw.

The problem is I did not take note when I removed the wires, so I am lost which is which now....

The red wire is hot, does that mean it is common? This is my 3 way switch..
 
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Old 02-29-20, 04:56 PM
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At this point the fact the red is hot is of little help.
BUT..... we know red is hot. Now go to the other switch and flip it. Now see which one becomes live. Red will no longer be hot and another wire will be.

When you find the other wire that becomes hot..... that wire and the red wire will be travelers. The remaining wire will be the common.
 
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Old 02-29-20, 05:09 PM
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The problem is I cannot find any other switch that control the same lights. and this is exactly the reason I did not realized it is a 3 way.
 
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Old 02-29-20, 05:21 PM
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If you flip the switch and the red wire stays hot it is the common.

OR

You can connect the red wire to one of the other wires and if the light turns on then the wire you connected the red to is the common wire.
 
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Old 02-29-20, 05:32 PM
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hmmm, before i do the above test.

I noticed something when I test the voltage between the wires.

The red and the bare copper wire gives me 120, but the white and the bare gives me 50.x, why I have this number?
 
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Old 02-29-20, 05:44 PM
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"You can connect the red wire to one of the other wires and if the light turns on then the wire you connected the red to is the common wire."

I did the test, when I touch the red and the black, the lights turned on, and I saw very small sparks between the touched wires.


 
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Old 02-29-20, 05:52 PM
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I did the test, when I touch the red and the black, the lights turned on, and I saw very small sparks between the touched wires.
Sparks are normal when making or breaking a connection under load.
 
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Old 02-29-20, 06:34 PM
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If there is no other apparent switch that controls that circuit.... then you can cap off the white and connect just the black and red to a standard single pole switch.

We do know now that the red and white are travelers and the black is common if you ever locate the missing three way switch.
 
 

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