How to tap to a light switch?

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  #1  
Old 06-29-15, 04:53 PM
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How to tap to a light switch?

Just got a new light switch but it has 2 brass screws + ground.
The box has regular 12-2 cable coming in so there is white, black and neutral.
Have 2 questions:

How do I connect this switch since I only have 1 black wire?
I would also like to run a new cable (always on) to a new outlet that would be end of run..... how to do ?
I was thinking I could pig tail the incoming power cable and then get the switch and the new outlet connected but still not sure how to do it with a switch that only has 2 brass screws.

thanks!
 
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  #2  
Old 06-29-15, 05:23 PM
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Just got a new light switch but it has 2 brass screws + ground.
The box has regular 12-2 cable coming in so there is white, black and neutral.
If there is really only one cable (pull all the wires out and really look) you have a switch loop and the the white was supposed to be marked some color other then white green or gray such as black or red to indicate it is an ungrounded conductor.
I was thinking I could pig tail the incoming power cable and then get the switch and the new outlet connected
If it is a switch loop there is no incoming power cable. There is no neutral so you can't connect a receptacle.

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  #3  
Old 06-29-15, 08:47 PM
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yes - you are right...I checked the run and see that the power comes to the light and then it goes to the switch....so the white should have been re-labeled as black
 
  #4  
Old 06-30-15, 03:19 AM
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Correct, the white is a constant hot.
 
  #5  
Old 06-30-15, 05:44 AM
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With the wiring as described you cannot run a new cable from this switch box to a new receptacle.

In other words you cannot tap this light switch.

You need to run the cable from the light fixture box (where the power comes in) or run a cable from a different recepbacle location to your new receptacle (some obscure limitations apply).
 
  #6  
Old 06-30-15, 07:24 PM
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by the way.... why is it that most of the time I see duplex receptacle connected by white wire going to the top screw and the black to the bottom ?
Since the receptacle terminals are connected I would imagine to just connect white and black to the top terminals.
 
  #7  
Old 07-01-15, 06:33 AM
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I have not noticed any pattern or habit of connecting the black wire to the top gold screw and the white neutral to the bottom silver screw.

Must be because hardly anybody uses his right hand to wield the screwdriver to attach the black wire and his left hand to wield the screwdriver for the white wire. Instead he might always screw the wire to the top right screw as he sees it and when the receptcle is finally stuffed into a vertical box the other wire is on the bottom left screw.
 
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Old 07-01-15, 07:51 PM
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I am not an electrician so can't say I have good sampling here but just that almost every diagram / drawing etc... shows the white wire connected to the top silver and the black wire to the bottom gold screw.....as if this mattered.
 
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Old 07-02-15, 07:29 AM
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why is it that most of the time I see duplex receptacle connected by white wire going to the top screw and the black to the bottom ?
There is no top or bottom to a duplex receptacle. Your comment makes no sense. As long as the wires are connected to a duplex receptacle with white to silver screw and black to brass screw all is good.
 
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Old 07-02-15, 06:12 PM
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CasualJoe....I guess you didn't understand my question....BECAUSE it doesn't matter if you attach the wire to the top or bottom screw....why is it that every picture, diagram and book shows it that way, when in fact it would make more sense to just connect the wires on the same level.....would make it easier for future when you decide to extend the run and add a receptacle after.

I was just wondering why most books/website illustrate it with the wires diagonal of each other.
 
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Old 07-02-15, 06:14 PM
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I have never seen that. Some examples would be interesting to see.
 
  #12  
Old 07-02-15, 06:25 PM
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It is easier to loop the wire around the screw from the outside instead of from between the two screws. Functionality it makes no difference .
 
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Old 07-03-15, 11:43 AM
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CasualJoe....I guess you didn't understand my question
I understood perfectly, I guess you didn't understand the answer.

There is no top or bottom to a duplex recetacle therefore there is no top or bottom screw. Now, what you are talking about makes no difference.
 
  #14  
Old 07-03-15, 02:37 PM
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Question



[Image removed per DMCA request - ibtyen]

I think he is referring to the four screws as shown.
 

Last edited by IBtyen; 08-10-18 at 12:17 PM.
  #15  
Old 07-03-15, 03:52 PM
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We know what screws he is talking about and your image is actually the opposite of what he contends.
 
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