Quick Question about 3 way wiring

Old 11-19-08, 01:14 PM
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Quick Question about 3 way wiring

Ok, so I have one circuit in my basement for all of my lights. And all of those lights (6 can lights 50w bulbs) are controlled by a 3 way dimmer and switch.

Since two of those lights are sorta separated from the rest of the basement, I want to put 2 of them on a separate switch from the other 4. I decided to do a end of run switch, so that I wouldn't have to waste wire running to the switch first.

So my thought was to go to the wire running between the dimmer and the switch, and put in a junction box. Then connect a 2 wire from the junction box to the first light of the separated 2. Then I would connect the hot wire from the junction box to the white wire (made hot with tape) that runs to the new switch. Then connect the black wire from the switch into the black wire of the fixture.

problem is this.. In the 3 wire cable that I put the junction box in the middle of.. when the switch is flipped back or forth, the white and red wires take turns being hot. Is this normal. So I can't hook the white wire that goes to the new fixture to either one of those. The only thing that I can do is hook the white wire to the ground wires in the junction box. Otherwise it doesn't work. Is this ok??

I tried to draw this up, but it still may be confusing..

Any help would be appreciated..
Old 11-19-08, 02:24 PM
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It looks like you tapped in to the 3-way switch carriers. Turn off the cricuit breaker. Take the switch covers off. Note how many cables are in the switch boxes and which wires are connected to the switch and dimmer. Is your basement unfinished? If it is, trace out where the cables are routed from switches to lights.
Old 11-19-08, 02:36 PM
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yeah I did tap into the 3 way switch carrier cable. But I wanted to get a close always hot power source that wouldn't be cut off using either one of those switches. If I use a cable coming off of one of the lights from the switch, then I'll only have power when those lights are switched on. I want to be able to have a totally independent switch, but on the same circuit.
Old 11-19-08, 03:00 PM
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You can't use a three-way traveler cable for power. All three conductors in the cable are hot - one always hot, two switched hots; there is no neutral in that cable.

You cannot use the ground as a neutral conductor as that creates an electrocution hazard.

You'll have to pick up power from the box where is enters the lighting circuit which will be at one of the two switches or at the first light fixture after the switches. Examination of the wiring at each of these locations is required to tell which one is right.
Old 11-19-08, 03:09 PM
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Find where the power comes into the threeways and pickup your new light feed there. The hot and neutral should travel to your circuit together. Yes it's normal for the travelers to go on and off.
Old 11-19-08, 03:34 PM
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The only way you can able get this set up working right is by get the power source at the switch location it will be one of the two locations depending on the connetion there.

It is very typical for three way trallivers to switch circuits between the two.

That is normal for 3 way switch to function like this.

Old 11-19-08, 05:00 PM
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Thanks guys...
This clears it up perfectly.. I was trying to just use a shorter route if possible. But I will go ahead and run a cable from the original power source at the switch. I know exactly which cable it is and where it needs to go..

Thanks again..


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