four-way switch wiring problem

Reply

  #1  
Old 02-13-05, 09:11 AM
Member
Thread Starter
Join Date: Jan 2003
Location: usa
Posts: 103
four-way switch wiring problem

My kitchen lights (installed last year by a professional) are switched "fourway" - two three-terminal switches and one four-terminal switch. i wanted to replace one of the three-way switches with a three-way dimmer. i notice that the dimmer has one black and two red leads. but the in-wall wiring to this position is two blacks and one red, and the red goes to one side of the switch body, while the two balcks are on the other side - makes logical and physical sense to me. Yet Lutron's diagram for this setup shows two *reds* between switches, with a black from the breaker and a lack to the load. I believe that the electrician does things by the book. anyway, i can't find a way to make the replacement dimmer/switch setup work - one of the other switches is not able to flip the load on and off, although the other two do work as expected (i.e., i end up with a "three way" system. any ideas (besides calling John to copme back to install the dimmer switch?)
 
Sponsored Links
  #2  
Old 02-13-05, 09:34 AM
rikamy
Visiting Guest
Posts: n/a
switch

On a three way switch you have a common and two travelers. The common is usually designated by a black terminal screw and the travelers have gold colored screw terminal. The colors don't have to be a black and two reds whatsoever when originally wired. This was just lutrons way of marking the common and the travelers. If you match the common to common and travelers up, it should work. If not, but you know you have the common from the old switch to the common on the dimmer, just try switching the travelers around..
 
  #3  
Old 02-13-05, 02:49 PM
Member
Thread Starter
Join Date: Jan 2003
Location: usa
Posts: 103
that is exactly what i thought. before i posted, i tried ignoring what the colors were, and just figured "two of color x" go to "two of color y".. no good. then i switched the travelers (which actually should not matter, all it does is switch whether "up" or "down" is "on" for a given setting of the other two switches).. and still ng. but thanks for verifying my thought process..
 
  #4  
Old 02-13-05, 02:55 PM
Member
Join Date: Sep 2000
Location: United States
Posts: 18,497
As you noticed, it doesn't make much difference to switch the travelers. The important thing is which wire is on the common. You need to switch one of the travelers with the common, and if that doesn't work, switch the other traveler with the common.
 
  #5  
Old 02-13-05, 03:35 PM
Savant
Visiting Guest
Posts: n/a
Originally Posted by bruce_hyman
i tried ignoring what the colors were, and just figured "two of color x" go to "two of color y".. no good.
Just ignore the colours period. (with the exception of a plain white wire of course) Switch wires can be any colour: red, black, or white with black tape on it.

So let's back up and assist your logic a bit.

On a three-way switch setup, as has been mentioned there are TWO travellers. However, let's forget the travellers for a moment. At one of the three-way switches the COMMON will be the LINE power, and at the other of the three-ways switches the COMMON will be the power return that is fed back to the lighting device.

First off, I would suggest you find out what end of the three-way setup you are at. With the power off, take off whatever you have on that stitch-box and separate the wires. Now turn the power on and CAREFULLY test the wires for power, with one of your tester leads touching the ground wire (or the metal box) and the other testing each of the three wires. Once you test all three wires, flip your four-way switch and try again.

If this box is at the power end, you will only have one live wire, regardless of how you flip the other switches. If that is the case mark that wire as COMMON and the others as TRAVELLERS.

If this box is at the return-feed end, you will have one wire live, then when you flip one of the switches another wire will go live. The wire that is NEVER live is the COMMON, and the two live wires are the TRAVELLERS.

Just as an aside, when figuring out what screw terminals are what on a three-way switch, aside from one being a different colour, in most cases both travellers will NOT be on the same side. So there will be a common and one traveller on one side, and a lone traveller on the other.

Make sure to mark the wires regardless of what end it is.

Once you figure out your setup, get the old SWITCH back in the wall and get it working properly as a three-way switch. After you have accomplished that, only then can you consider installing that three-way dimmer. (perhaps it is defective) If you have tested the setup, marked the wires, have a regular three-way switch working, and still can't get the dimmer to work, then replace the dimmer.

Regards,

Savant
 
  #6  
Old 02-14-05, 05:09 AM
Member
Thread Starter
Join Date: Jan 2003
Location: usa
Posts: 103
well, i will follow your guidance in the next day or so. the 3-way switch is back in place, and everything is operating as expected.. it *is* weird that the three-way dimmer isnt, but i suppose it oculd be defective. willlet you know..
 
Reply

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


Thread Tools
Search this Thread
Display Modes
'