Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 05-03-2011, 10:01 AM   #1
Member
 
Join Date: Mar 2009
Posts: 35
Rewards Points: 25
Default

Two dimmers, two circuits, one box, one supply


I've got two sets of can lights independently controlled by separate dimmers. They are on different circuits. They were installed by a professional electrician. We are just switching out the color of the dimmers so I thought it would just be a straight up replacement. Well the wires got somehow crossed and I lost my reference point. Here's what is in the box:

1 B/W/G that is the supply
2 B/W/G going to the cans

Two of the wires are new looking from when they installed the cans and so I thought the old wire would have been the supply. But it turns out that one of the newer wires is the supply. I tried nutting all the whites together and pig tailing the blacks but that's when they were a separate circuit cause it just tripped the breaker.

I've tried many configurations and currently I have the switches so that one works, but the other only works if the first one is on. Seems like I'm close.

Any help?

thanks!

oh yeah, it's not a 3 way and there is no red wiring. I can easily take a picture and upload if that will help.


Last edited by justinae; 05-03-2011 at 10:04 AM.
justinae is offline   Reply With Quote
Old 05-03-2011, 10:54 AM   #2
Member
 
joed's Avatar
 
Join Date: Mar 2005
Location: Welland, Ontario
Posts: 7,832
Rewards Points: 2,458
Blog Entries: 4
Default

Two dimmers, two circuits, one box, one supply


Two dimmers and two cables means there is no feed. You have two switch loops. Connect the black and white from one cable to one dimmer and the BW from the other cable to the other dimmer. Connect all the grounds together and to the green wire from the dimmer if there is one.

If there is more than two cable then tell us ALL the cables in the box.

__________________
Do not PM with questions that can be asked in a forum. I will not respond.
joed is online now   Reply With Quote
Old 05-03-2011, 11:04 AM   #3
Electrician
 
SD515's Avatar
 
Join Date: Aug 2008
Location: Near Jackson Michigan Area
Posts: 1,450
Rewards Points: 500
Default

Two dimmers, two circuits, one box, one supply


I suspect that one of your cables entering the switch box may be a switch leg from the cans. If it is, and was done correctly, power would enter the switch box on the white wire, and when you tied all the whites together, it created a 'dead-short' and tripped the breaker.

Using a voltmeter/tester, you can determine which is which, if that's the case. If you're not comfortable working with live electricity, stop (!) and have a qualified person look at the situation.

If it is as I suspect, the cable from the panel (source cable) is going to have voltage from black to white and black to ground. The cable that goes to one set of cans isn't going to have voltage black to white, black to ground, or white to ground. The third cable, if it is a switch leg, is going to have voltage on either the black or white to ground, but not black to white. Per code, it should be on the white, and the white re-marked (a black sharpie works nice).
__________________
Kyle

Just because you can, doesn't always mean you should

Last edited by SD515; 05-03-2011 at 11:09 AM.
SD515 is offline   Reply With Quote
Old 05-03-2011, 11:05 AM   #4
Electrician
 
SD515's Avatar
 
Join Date: Aug 2008
Location: Near Jackson Michigan Area
Posts: 1,450
Rewards Points: 500
Default

Two dimmers, two circuits, one box, one supply


Joe, I thought the OP meant there are 3 cables in the sw box. Maybe I mis-understood.
__________________
Kyle

Just because you can, doesn't always mean you should
SD515 is offline   Reply With Quote
Old 05-03-2011, 11:24 AM   #5
Member
 
Join Date: Mar 2009
Posts: 35
Rewards Points: 25
Default

Two dimmers, two circuits, one box, one supply


Yes three romex wires total coming in.

Im fine working live. That's how I found out which was the black supply. Don't have a volt tester so I can test if white is hot.

Last edited by justinae; 05-03-2011 at 11:27 AM.
justinae is offline   Reply With Quote
Old 05-03-2011, 11:31 AM   #6
Electrician
 
SD515's Avatar
 
Join Date: Aug 2008
Location: Near Jackson Michigan Area
Posts: 1,450
Rewards Points: 500
Default

Two dimmers, two circuits, one box, one supply


I'd suggest getting a inexpensive voltmeter...handy to have around...and test as I described above.
__________________
Kyle

Just because you can, doesn't always mean you should
SD515 is offline   Reply With Quote
Old 05-03-2011, 11:45 AM   #7
Member
 
Join Date: Mar 2009
Posts: 35
Rewards Points: 25
Default

Two dimmers, two circuits, one box, one supply


Before I do that is it correct that I should have 3 blacks and 1 white and it is some combination of those 4 connecting to the 4 terminals. Dies it matter whether I connect to the bottom or the top terminal if they are both gold colored?
justinae is offline   Reply With Quote
Old 05-03-2011, 12:26 PM   #8
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 6,964
Rewards Points: 2,024
Default

Two dimmers, two circuits, one box, one supply


Three Romex cables with 3 blacks and one white, something's missing. THere's got to be more wires.

Quote:
I'm fine working live
You can use a light fixture such as a table lamp for a voltage tester in this situation. Cut two 4 foot sections of #14 to #20 gauge single conductor wire, attach one wire to each plug prong, tape it up well so no metal is exposed, and use the two free ends to test for presence or absence of line voltage and find which wire is the feed.
__________________
Forget super sized fries. The Washington Redskins could promote healthy eating with First Lady Obama by choosing a (red skinned) turnip for a mascot.

Last edited by AllanJ; 05-03-2011 at 12:30 PM.
AllanJ is online now   Reply With Quote
Old 05-03-2011, 01:30 PM   #9
Electrician
 
SD515's Avatar
 
Join Date: Aug 2008
Location: Near Jackson Michigan Area
Posts: 1,450
Rewards Points: 500
Default

Two dimmers, two circuits, one box, one supply


???

You said you have 3 cables coming in. That should be 6 wires not including grounds. Are you eliminating the cable you know is a source cable? Leaving 4 wires (2 cables)?

If that’s the case, I’d bet you have one cable that has blk & wht, and the other has 2 blacks, and that cable has had its white re-marked to black. And if that’s true, I’d bet that the cable with 2 blacks gets hooked to one switch, one black to a terminal, the other black to the other terminal. That switch is done.

The other switch gets the black of the source hooked to it, the black of the last cable hooked to it, and whites tied together.

Make sense?
__________________
Kyle

Just because you can, doesn't always mean you should
SD515 is offline   Reply With Quote
Old 05-03-2011, 01:35 PM   #10
Member
 
Join Date: Mar 2009
Posts: 35
Rewards Points: 25
Default

Two dimmers, two circuits, one box, one supply


The electrician just left. There was an outlet on the circuit that had been switched before and when it was replaced was unswitched. Problem solved!
Thank you for all the fast help.

justinae is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Rerouting stack and water supply for an added beam WillK Plumbing 1 03-02-2011 08:27 AM
Extending Water Supply Box In Laundry Room hsl Building & Construction 0 11-18-2009 09:21 AM
Main Supply Line Vibrates When Cold Water Runs kmcbee1971 Plumbing 1 01-13-2009 09:26 PM
Darn. A leak in my main supply from street, Galvanized. In foundation under slab? twilightcall Plumbing 2 07-31-2008 12:22 AM
Galvenized supply to PEX, How to make connection? twilightcall Plumbing 4 07-28-2008 09:28 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.