Replacing dimmer switch

Old 02-15-15, 02:24 PM
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Replacing dimmer switch

Trying to replace a normal light switch with a dimmer switch in my bathroom. When removing the old switch there are 2 black wires wrapped around the bottom screw, and 1 black wire wrapped around the top screw (first image). Given outlets in another room and the bathroom lights are off when i turned off at the mains, I am assuming the bottom 2 black wires are for those, and the black wire on the top screw are for the power feed. If thats the case, can I still connect the 2 black wires to the bottom black wire of the new switch, the top to the top, and cap the ground on the new switch? (second image)

Or will that somehow 'dim' my power outlets?
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Old 02-15-15, 02:44 PM
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Welcome to the forums.

Twist the two black wires together that were on one screw and attach one of the dimmer wires.
Attach the other dimmer wire to the single black wire.

If you don't see any ground wires in the box to connect to... the dimmer should be grounded thru the two mounting screws in the metal box.
Old 02-15-15, 02:44 PM
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The two wires that were together on the old switch must remain together on the new switch as you said. Just be sure not to mix them up and it will work. If your box isn't grounded (such as BX or metal conduit) then capping the ground wire is okay.
Old 02-15-15, 03:09 PM
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The two wires on the same screw were most likely power in and power out. The single was the switched hot to the fixture.

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