Black connect to ground


  #1  
Old 09-07-20, 11:32 AM
T
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Black connect to ground

Went to replace an existing single pole dimmer switch. When pulling out the existing dimmer, there are 3 black wires connected to the switch. 2 blacks are connected normal for a light switch however the 3rd black wire is connected to the green ground screw on the existing/ working switch. Can anyone explain why a black wire is connected to the ground on the existing dimmer switch? Any input or direction would be greatly appreciated.

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  #2  
Old 09-07-20, 01:20 PM
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There is no situation where a black will connect to the ground screw.
Most likely situation is that a three way should have been used there and some uneducated person bought a single pole switch and connected the third wire to the third screw thinking three screws on old. Three screws on new. This must be correct..
 
  #3  
Old 09-07-20, 03:37 PM
Z
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Where does that black wire go?

Sometimes, people use a spare wire to ground the switch to the box. It should be stripped bare or at least marked green to indicate a ground, but maybe it's a simple explanation?
 
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Old 09-10-20, 07:58 AM
T
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Thank you for the responses and feedback. Do you think it would safe to just cap that 3rd black wire and proceed with wiring as a single pole? Iím not sure where the 3rd black wire ultimately goes.
 
  #5  
Old 09-10-20, 10:38 AM
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If you can't determine the black wire connected to the ground screw on the old switch is connected to ground at the other end, wire nut it and leave it in the electrical box.
 
 

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