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qchawkfan 01-24-2010 07:44 AM

4 lights finished ceiling wire through joist??
1 Attachment(s)
here's a rough paint drawing
i'm putting in recessed lights in a finished basement ceiling, want to run 2 separate switches for 2 and 2

i can access the ceiling from the unfinished portion of the basment, no problem - BUT i'm reading that I need to run 12-3 wire between the 2 lights i want to control together - is this correct?
how can i do that WITHOUT opening my ceiling in any way? i don't know how many joists in between so i just put a bunch of lines - there's probably 5?

and there's a ceiling fan in the mix - but i'm not messing with that wiring just added for the fun of it in the drawing

HouseHelper 01-24-2010 08:38 AM

If you can run wire from the switch to each light, you do not need any wiring between the lights.

joed 01-24-2010 08:53 AM

You only need 12/3 if it was a switch loop. In your drawing you only need 12/2.

qchawkfan 01-24-2010 10:42 AM

1 Attachment(s)
so i got a junction box and i have to bring power from an outlet to the new lights - then go to the switches

what's the wiring on that?

I'll have 12-2 from each light

joed 01-24-2010 11:22 AM

at receptacle
White from switch to power black on receptacle.
White from lights to remaining whites
Black from switch and blakcs from light together with wire nut.

Make sure the receptacle box is big enough for all the cables. If you only one cable now then adding three cables and counting the receptacle means you need 32.5 ci box minimum.

qchawkfan 01-24-2010 11:41 AM

can you explain that with 2 switches?

I will ahve one power source, 2 light switches - single pole on/off
4 lights total - but running 2 and 2

AllanJ 01-24-2010 01:58 PM

There are numerous permutations on how to skin a cat but here is one for now.

Get a 50 cubic inch box for junctions.

12-2 cables coming in to that box:

Four for the lights.
One for the fan.
One for the power
Three for the two light switches and fan switch respectively

Except for the whites to the switches, connect all whites together in the junction box. You will probably need to make two wire nutted clusters connected by a short length of white wire.

Connect two light blacks to one switch black. The other two light blacks to another switch black. Connect the fan black to the last switch black.

Power black to the (three) switch whites.

qchawkfan 01-24-2010 03:43 PM

hey thanks just finished finding my path for the wires

the fan is not involved in the new lights at all - it's only run on a pull chain and that circuit is not accessible

do i need two separate lines of 12-2 to the switches or just one and then pigtail? can you explain it if i pigtail?

AllanJ 01-24-2010 04:01 PM

With two switches you need either two 12-2's or one 12-3.

In the case of the 12-3, the white is the shared incoming unswitched power and at the switch box you would use two black pigtails to connect it to both switches.

You may not use just two 12-2's to feed three switches because a white may not be the switched power coming back from one of the switches.

qchawkfan 01-24-2010 05:36 PM

sorry i'm just not getting this

what i'm doing is wiring the lights at one point in the unfinished section so i was going to junction off an exisiting outlet right there

then putting the switches at a different location - so i'm wondering do i junction the lights together and then take ONE 12-2 to the two switches and then pig tail from one switch to the next - or do i have to junction and then take 2 separate 12-2 to the two switches - one for each ya know.

my path for the wiring is a real pain so i'm hoping i only need to travel one wire that route and if i need 12-3 it's going to wait until tomorrow cuz' i'll need to run to the store for more - i only have about 6 feet and i'll need about 20 or more

AllanJ 01-24-2010 06:35 PM

Can you show on your picture where the power comes from and where the switches will be and where the junction box is? Update the paths of the wires to show any changes you made from what you showed above.

Alternatively you can connect the second light to the first light and connect the first light using one cable to the switch box or junction box. Then connect the fourth light to the third light and connect the third light to the switch box or junction box.

You cannot make use of two switches by running one 12-2 cable from the lights to them. However just one 12-2 power feed cable from the nearest receptacle box or from the panel, to the junction box, is enough for all the lights.

qchawkfan 01-24-2010 07:43 PM

1 Attachment(s)
i don't know how to connect the two sets of light - to run separate
want to run 2 and 2 - connect to the power source from the outlet - then go to the light switches

AllanJ 01-24-2010 11:00 PM

1 Attachment(s)
In the diagram I drew, the colored lines are 12-2 cables.

This is how you treat the red and blue blobs.

Excluding the white wires from the cables shown as dotted red and dotted blue, connect all white wires in the junction box together.

For the red cables, solid and dotted, connect all the blacks together.

For the blue cables, solid and dotted, connect all the blacks togehter.

Connect the cyan cable black to the dotted red cable white and the dotted blue cable white.

qchawkfan 01-25-2010 05:15 AM

thanks for taking the time for a diagram

so you're saying 2 separate 12-2 lines from the junction box to the switches

is there ANY way this will work with running one wire to the switches with a 12-3 line? it's a real pain feeding/fishing lines

AllanJ 01-25-2010 07:59 AM

Yes, using one 12-3 takes the place of both dotted lines above.

Connect the blacks from the red cables to the red wire and connect the blacks from the blue cables to the black wire. Connect the power (cyan) black to the 12-3 white.

If the switches are not in the same box you would run a 12-2 cable between the switches. Here, in the first box connect a black pigtail to the two whites to feed that switch. Connect the other wires from the 12-3 one to the switch and the other to the continuation 12-2 cable black dependin on which switch you want to control which light.

In all cases where a white wire is connected to a switch or to a non-white wire, put a band of black (or red) tape on both ends.

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