Electrical Wiring for a double light switch

[BucksPA]

I am feeling mighty discouraged at this very moment as I cant seem to do the equivalent of changing a tire right now by installing a double light switch. Makes me wonder how i was able to complete my control panel build. Somehow that worked.

Here's the plan. In my garage the light switch controls, go figure, the light. I want to remove the switch and hook up a double switch (vertical), where one switch stays hooked up to the garage light and use the other switch for a motion light outside of the garage.

Please look at the wiring diagram i just whipped together and let me know if you need anything other information as I am stumped.

 

[cracked1]

I dunno... It's hard to tell what you're planning to do from that little red X...

 

[BucksPA]

? i can view it just fine

 

[Bobby_M]

Why would a switch have two whites? Can you give us a brand/model number for the switch?

 

[cracked1]

Strange... This is one of the first times I can't see a pic that others can.

Regardless... Most double switches will have one power wire coming in (black) to power both switches, one power going out from one switch and one power out from the other. Then the neutrals (white) are tied together.

Kinda like this...

Remember, colors may not be the same and your current wiring may be different! This is just a "normal" diagram.

 

[Spooner61]

Why control a motion sensitive light with a switch

 

[lschiavo]

You will have a hot wire (line) feeding your switch box. This will be tied to one side of each switch. The other side of each switch will be tied to each lighting load.

If power is fed first to the existing lighting box, you may not have a neutral in the switchbox. A white wire in a switch box does not necessarily equal neutral.

 

[lschiavo]

Why control a motion sensitive light with a switch

Mine are all that way in case I want them off for some reason.

 

[bottlebomber]

Why control a motion sensitive light with a switch

My home has this. A double flick of the light switch will turn the light on as an ordinary flood light. Turning it off for 5 seconds then back on makes it a motion sensor light.

 

[BucksPA]

Why would a switch have two whites? Can you give us a brand/model number for the switch?

Pass & Seymour tm811

 

[BucksPA]

Why control a motion sensitive light with a switch

The switch can override the motion sensor to keep light on constantly. That way I don't have to do jumping jacks every 5 10 or 15 minutes

 

[BucksPA]

You will have a hot wire (line) feeding your switch box. This will be tied to one side of each switch. The other side of each switch will be tied to each lighting load.

If power is fed first to the existing lighting box, you may not have a neutral in the switchbox. A white wire in a switch box does not necessarily equal neutral.

Yeah I don't think there is a neutral wire. Any recommendations from here? Also, ill have to split off the hot wire in order to tie it to each switch. This is what your suggesting?

 

[Bobby_M]

Here's what I think you've got. It's pretty common to run the hot/neutral/ground cable over to the light fixture box and then run a switch loop from there to the location of the switch. The hot comes down the black wire and then the switched hot goes back to the light via the white wire which technically should have a piece of black tape wrapped around it in the switch box.

This is especially common on the second floor or any other layout with attic access. It's a lot easier to rough in by running all the lines up into the attic and directly to the fixtures rather than bore through 80 studs to get to the switch box first.

If you only have one romex/bx cable entering your switch box now then you can be pretty sure you have a switch loop and no neutral.

 

[BucksPA]

Bobby. that sounds about right. there is attic access above the garage and and the switch appears to be set up like your diagram. i'll have to check when i get home. so in order for me to hook up a second light fixture to be operated by a second switch, I'll need to hardwire the flood light in my attic where the garage light is hardwired, and then drop another loop wire to the second switch?

Am i making progress?

 

[lschiavo]

Yeah I don't think there is a neutral wire. Any recommendations from here? Also, ill have to split off the hot wire in order to tie it to each switch. This is what your suggesting?

If you need to split the hot to feed two switches, wirenut two short pieces (pigtails) to it and connect those to your switches.

It looks like Bobby has you covered with the diagram. There are a few ways you could wire this but bottom line is to have line and load at the switch and load and neutral at the light. Diagrams are much better than words for this stuff....

 

[Bobby_M]

If you do have a switch loop, there are a lot of different way to reconfigure or add on to give you the function you're looking for. I'm going to assume that you have drywall on the walls and can't easily pull out the existing switch loop of romex.

One way: Run some 14/2 between the current light and the new light connecting only the grounds and neutrals (remeber that one of the white wires in that box is really the switched hot and not a neutral). Run another 14/2 out to the switch box. You only really need to use one conductor between the load terminal on the newly added switch and the wire coming from your new light box. However, they don't make 1 conductor romex.

The other way, which may end up using more or less feet of cable, is to run 14/2 romex from the current light box to the new light box bringing in hot/neutral/ground. Then run another 14/2 from there back to the switch box as the switch loop for that circuit. Of course, you already have a line (hot) in the switch box from the other existing run but you'll be needing the conductor to act as the load connection for the new light.


If I were rebuilding this whole thing, I'd replace the existing switch loop with 14/3 romex using black as the line to the switch and then the white for the load to the flourescent and red for the load to the new light. Then you just run 14/2 between the two light boxes where the black connects to the red and the neutral and ground is all tied together. Does that make sense?

 

[BucksPA]

it makes perfect sense now that you explained it and my old man's buddy explained it--both the same as your first way. I'll be tying up all the neutrals together from the power source and both lights, running 1 hot from each light (2 lights) to the switch and running the hot from the power source to the switch as well.

like this: Should this work?

 

[BucksPA]

got it working today just the way i intended. thanks for your help