Wiring a motion sensing light switch


  #1  
Old 09-02-20, 03:52 PM
E
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Wiring a motion sensing light switch

Iíve wired a couple of these but the wiring on the switch itís replacing is confusing me. This is in my laundry room, the switch is the only one and it turns the overhead light on/off. It doesnít control any other fixtures.

there are three Romex coming into the switch box. All three white wires are bundled together as are all three grounds. The three black wires go to the switch - one to the top terminal (marked negative) and two to the bottom terminal (marked positive).

the motion switch has two black wires, one bare, one green. The last two are easy enough - wire those to the collection of grounds. Not sure what to do with the two black wires and the three in the box. Not sure why there are three in the box with only one fixture. Any ideas?


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  #2  
Old 09-02-20, 04:12 PM
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The two black wires on one screw should stay together and be treated as one wire when connecting to the new switch.
 
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Old 09-02-20, 04:22 PM
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Ok, thx. Thatís what I figured, I just wanted to be sure. I am confused about the three romex coming into the box.
 
  #4  
Old 09-02-20, 06:28 PM
J
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I am confused about the three romex coming into the box.
One is power from the panel.
one is unswitched power to another part of the circuit.
one is switched power to your light.
 
 

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