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Discussion Starter · #1 · (Edited)
I'm looking for help wiring new lights in my basement. The room is long so I am installing 12 recessed lights in the ceiling. I want 1/2 the room to be controlled using 3 way switches and the other 1/2 to use a single pole switch. Switch 1 & switch 2 are the 3 way switches controlling cans 1 - 6. Cans 7 - 12 will be controlled by switch 3. The live feed currently goes into switch 1. My initial thought is that switch 1 leads to can 1 and to switch 2. Switch 3 leads to can 7. See below:
Code:
feed
|
s1-------------s2-------s3
|              |        |
c1-----c3------c5      c7------c9-----c11
|      |       |        |      |       |
c2     c4      c6      c8     c10     c12
Feed to S1 is 12-2 romex cable. S1 to S2 is 12-3 romex cable. All other wiring is currently 12-2 romex cable. S2 & S3 are both dimmer switches to control their respective halves of the room.

Now, when S1 is off, toggling S2 has no effect nor does S3. If S1 is on and S2 is off, all lights are off. If S1 & S2 are on but S3 is off, cans 1 - 6 are on, 7 - 12 are off. If all 3 switches are on, all 12 cans are on. I think I understand the issue, but I want to know if its even possible. Any help and suggestions would be appreciated. Thank you.
 

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Your cabling is correct, your 3 way sw make up is just wrong.

*********
Wait...edit....maybe the cable is incorrect. I can't interpet your drawing. I was assuming you ran both switch legs to the 2 gang box and the only thing at s2 was a 3 wire cable.

If so, continue on. If not, describe the cable paths.
*************


Send the power to s2 on the black wire, attach it to the common terminal and use the red and white for travelers. The black wire feeding lights 1-6 will go to the common terminal on s1.

In the 2 gang box:

all 2 wire whites together.

black power in ties to black in 3 wire and a pigtail to power s3

black from lights 1-6 to common, red/white in 3 wire to other two terminals.

black hot pigtail and black from cans 7-12 to sw3

In s2, black to common, red/white to other two terminals.

feed
:
:
s1............................................(3 wire).............s2
: :
: :
: :
: :...........................(2 wire switch leg).............................1 thru 6
:
:
:
:
s3............................(2 wire switch leg)...........................7 thru 12
 

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At the switch box you should have:

1 feed with neutral (120 volts)
3 switch legs
and 1 three wire for the three way.

Your have 3 switch legs, one of them is for the set of 3-way lights. This is your common for the 3-way switch at this box.

Tie together all of your ground wires including three pigtails to ground your switches. This is for safety.

Tie together all four white wires excluding the white from the three wire, that's one of your travelers for the three way.

Tie together the feed black wire, three wire black wire, and two pigtails for the 2 single pole switches.

Attach the red wire from the three wire to the last available terminal on the three-way switch and you're done.

Attach firmly all of the devices to the box, install cover.
 

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Discussion Starter · #4 · (Edited)
updated diagram

First, thank you "220/221" & "Magnettica" for replying so quickly. Sorry for the confusion. I did screw up my diagram. I do not currently have a connection between S2 & C5. The corrected diagram is shown below:

Code:
[FONT=Courier New]feed
|
s1-------------s2-------s3
|                       |
c1-----c3------c5      c7------c9-----c11
|      |       |        |      |       |
c2     c4      c6      c8     c10     c12[/FONT]
From S1 to S2 there is a single 12-3 cable. My suspicion is the only way to accomplish what I'm trying to do is to add another 12-2 cable from S1 to S3 (basically spliced right off the feed). Would that be correct? Or is it possible to power the 2nd 1/2 of the room (S3/C7-C12) from the first 1/2 using the existing or similar wiring?

So the 2 problems I have are:
1) How should I power the S3/C7-C12?
2) If S1 is off and S2 is on, shouldn't C1 - C6 light up? With the current wiring, they will only turn on if S1 is in the "on" position.

Thank you again for your help.
 

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My suspicion is the only way to accomplish what I'm trying to do is to add another 12-2 cable from S1 to S3
Correct. I originally thought s1 and s3 were in the same j box. Obviously not.

s3 cant come from s2

s3 needs a hot and a neutral. s2 has no neutral.


feed
:
:
s1............................................(3 wire).............s2
: :
: :
: :
: :...........................(2 wire switch leg).............................1 thru 6
:
:
:
:
s3............................(2 wire switch leg)...........................7 thru 12
 

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If the switches are in seperate boxes, which I believe they are based on your mention of 12-3 between S1 & S2, you don't have enough wires between S1 & S2. You need a hot & a neutral in order to continue the feed to S3, and you need 2 travelers between the 3-way switches. So you need a total of four conductors, but using standard cables, you'll end up with five (2 neutrals). You also don't need the connection between S1 and lights, the branch from S2 will feed the entire circuit. At the first box, you want to tap the hot to feed S1, as well as a new 12-2 to feed S3, use the red & black of the 12-3 as the travelers for the 3-ways, & join all your neutrals. the new feed for S3 could bypass the S2 box altogether, if that is physically possible.

At S2, the neutral of the 12-3 is joined to the neutral feeding cans 1-6, the two travelers feed S2 and the black wire of the lighting load is connected to S2.

Keith
 

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P.S.

If S1 & S2 are 3-way switches (and correctly wired), they don't have 'on' & 'off' positions, they simply toggle the lighting from its current state to it's opposite state.
 

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First, thank you "220/221" & "Magnettica" for replying so quickly.
Sorry to go OT; you're in good hands with the other guys. Are you a programmer? (I only ask b/c you quoted those strings and put an electrical diagram in a preformatted code block.. :thumbup:).
 
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