Light switch wiring diagram.

i386

Captain
Joined
Aug 24, 2004
Messages
3,548
I've been searching but all I'm coming up with is 3-way and 4-way switching which isn't what I'm trying to do.

There are two florescent lights in my basement shop. They are always on because no switch was ever installed for them. At one time, ceiling fans with pull chains were installed. The lights are in the middle of the circuit meaning there are outlets before and after the lights in the circuit that need to have constant power.

This was probably covered in a book I used to own but I loaned it out and you can guess the rest.
 

piper_chuck

Petty Officer 3rd Class
Joined
Aug 30, 2007
Messages
83
Re: Light switch wiring diagram.

Without seeing the exact setup it's hard to come up with the ideal, and safest, solution.

A solution might involve detaching the lights from the circuit and running a wire from the live circuit to the switch and then run another wire from the switch to the lights.

Note there are a number of safety related situations to consider while you're doing this. For example, I would not want the live wires that are feeding the outlets to be in the same box as the switched lighting wire. The odds of someone mistakenly thinking they can shut off the power by turning off the switch are too high for my comfort.
 

WizeOne

Commander
Joined
Mar 23, 2008
Messages
2,097
Re: Light switch wiring diagram.

I assume that currently there is a switch that controls the juice to the outlets and the lights? The only way I can see to do it is to re-route the power wires, from the light connections to an area where you can run them thru a switch and back. If you can't do this behind the drywall you may need to surface mount the Romex and cover it up with plastic channel.
 

joed

Lieutenant Junior Grade
Joined
Sep 28, 2002
Messages
1,135
Re: Light switch wiring diagram.

What do you want to happen. One switch for each light? or one switch controls both lights? Here's both drawings. Hope they are clear enough. Of course the switch needs to be in a box.
 

Attachments

  • 2 lt 2 sw.JPG
    2 lt 2 sw.JPG
    10.7 KB · Views: 0
  • 2 lt 1 sw.JPG
    2 lt 1 sw.JPG
    10.1 KB · Views: 0

Bigprairie1

Commander
Joined
Jun 13, 2007
Messages
2,568
Re: Light switch wiring diagram.

I386...assuming what you would like to do is get individual switches for both lights mounted somewhere local while leaving the existing plugs in the circuit intact here is my take and assumptions:
-The wire(s) connecting all of those components is currently a two conductor (w/ ground). This why they probably went to pull chains within the socket itself.;)
Ok, after the first plug in the circuit you are going to have to pull a new wire to replace the existing (2) conductor running to your first light. This new wire will will be a (3) conductor (w/ ground) and you need to run it to where you want your first light switch. You can leave the existing 2 conductor wire in the ceiling, etc but pull it out of the end point boxes to ensure it is fully dead with ends removed.
You will have to repeat this with (3) conductor wire substitution from the first light switch on to the last light. Then the final existing two conductor running from the last light to your last plug should still continously supply that final plug in the circuit.
I couldn't find my wiring diagram (and I've got some good ones), so I'm doing this a bit from memory...but I'll see what I come up with as far as some more along those lines.:)
All good:)
BP:cool:
 

i386

Captain
Joined
Aug 24, 2004
Messages
3,548
Re: Light switch wiring diagram.

What do you want to happen. One switch for each light? or one switch controls both lights? Here's both drawings. Hope they are clear enough. Of course the switch needs to be in a box.


Thanks. Both lights with one switch. It'll be done right. Just needed a jumping off point. Just what I needed.:)
 

i386

Captain
Joined
Aug 24, 2004
Messages
3,548
Re: Light switch wiring diagram.

I386...assuming what you would like to do is ...

Well I left out a few details because they weren't relevant to the question.;)

I'm converting one room in the basement to a woodworking shop. The existing 15amp circuit feeds all lights and outlets in the shop and an adjacent room. I'm rewiring so the circuit runs the lights and one outlet in the shop and everything in the adjacent room. I have a 20amp circuit that will run the outlets it the shop only. I'd also like to add a keyed switch to the 20 amp circuit so I can kill all the power tools when I'm not in the shop (kids).

Ok so I found this diagram which looks to be the same thing as y'all are telling me and I understand it.

http://www.indepthinfo.com/wire-switch/light-switch-outlet.shtml

In that diagram the switch comes after the light in the circuit. As long as I have my 12-3 between the light and the switch, is there any problem wiring the switch BEFORE the light?

BTW, does anyone know right off hand if Home Depot carries 12-3 by the foot? I won't really need a 25' box of it to do what I need.
 

joed

Lieutenant Junior Grade
Joined
Sep 28, 2002
Messages
1,135
Re: Light switch wiring diagram.

There is no problem putting the switch before the light.
 

Attachments

  • swlightrecpt.jpg
    swlightrecpt.jpg
    16.4 KB · Views: 0

i386

Captain
Joined
Aug 24, 2004
Messages
3,548
Re: Light switch wiring diagram.

Thanks. It looked good on paper but wanted to make sure. I've got the circuit drawn out and bill of materials. Looks like I can get the whole job done for about $100.
 
Top