How to add switch to existing box.

Old 06-07-13, 10:12 AM
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How to add switch to existing box.

Noob question here. I am installing a new closet light. There is an existing single light switch next to the closet that I want to add a new switch to. There are three incoming wires into the box, one from below that comes off an outlet, and the other two exit the top of the box. One of the two that exit the top has a red, black and white wire while the other two have only black and white. All 3 incoming white wires are capped, all three ground are capped with pigtail to switch, all three black wires capped with pigtail to switch, the remaining red wire to switch.

None of my books have this exact setup and I was unsure how to connect the added switch and incoming wire- probably simple but I want to be sure. Thanks much!
Old 06-07-13, 11:48 AM
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Those aren't wires from you description. They are cables. A wire is a single conductor.

So you have one 3-conductor cables and two 2 conductor cables. Pigtail your new switch to the group of blacks. Connect the black of the cable to the closet light to the other side of the new switch. Add the white of the new cable to the bundle of white.
Old 06-07-13, 12:39 PM
Join Date: Mar 2006
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Depending on several variables you may run into a box fill problem with too many conductors, clamps, switches and the like.

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