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Discussion Starter #1
I just installed four down lights in my living room with two three-way switches. I got a 12/3 running from one three way to the other three way.the switches are working fine except for one of the switches ... when I turn switch in the on position it shuts the lights off ..seems to be working backwards. is it just a simple reversing wires at that one switch? the red/ black on the 12/3??? thanks
 

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It depends on the other switch. If you flip the other switch this one will work the opposite of its current function.
There is no actual on/off on three way switches. If you want the function of one of the switches to work opposite of how it is now, you have two options.
1. Turn the switch over in the box.
2. Swap the traveller wires. The COMMON wire on the black must stay where it is.
 

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Naildriver
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Once you turn the lights off with the questionable switch, will the other switch turn them back on? Do they operate alright except for the switch positioning? If so, just turn the switch over in the box. You'll find, however, with that switch "up", the other switch will turn the lights off, and your switch will be turned "on". You can't win. With 3 way switches, it's a crap shoot as far as the position is concerned.
 

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Discussion Starter #4
Once you turn the lights off with the questionable switch, will the other switch turn them back on? Do they operate alright except for the switch positioning? If so, just turn the switch over in the box. You'll find, however, with that switch "up", the other switch will turn the lights off, and your switch will be turned "on". You can't win. With 3 way switches, it's a crap shoot as far as the position is concerned.
Yes the other switch does turn them on when questionable one is off. Yes they do operate ok.
 

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Naildriver
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As Joed said, there is no "on" or "off" position with a 3 way switch. It is the luck of the draw as to which switch will be up or down.
 

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It depends on the other switch. If you flip the other switch this one will work the opposite of its current function.
There is no actual on/off on three way switches. If you want the function of one of the switches to work opposite of how it is now, you have two options.
1. Turn the switch over in the box.
2. Swap the traveller wires. The COMMON wire on the black must stay where it is.
I've done a lot of 3-way and 4-way lighting circuits. One thing that just sets off my OC is upside down 3-way switches. Yes, if one looks closely on the front of the switch yoke, just below where the mounting screw is, one will see "top" on one end.
So, if both switches are installed correctly, when the light is off, they will either both be down or both be up. If not installed correctly, when the light is off, one will be down and the other up.
If power and the light come into one of the switch boxes, then wire the neutrals together. Option 1 is to put the power on the switch. Use the 12-3 to go to the other switch. Put the black and red on the 2 terminals that are not marked "common". Put the white wire on "common". Wire the white wire from the 12-3 to the black wire for the light in the first box. In option 2, one may wire nut the power to the white wire in the 12-3 to the other switch, configure the other switch like I wrote above, and then put the black wire from the light on the first switch. I know, I know, a black and a white wired together. One could use the white in the 12-3 as one of the travelers, however the code says a white can be hot and used as an "identifier" in switch legs, and I do that so that electricians see that wiring configuration and it jumps out at them.
If the power comes into the light fixture, and there is a wire to the switch box, a 12-2, you will see what I'm talking about with the "identifier" business. The white would be hot and on the top part of the single pole switch if wired correctly. In this case to put in 2-3-ways, one would again put the white wire coming from the light fixture on the common of the first switch, and again wire nut the black wire from the light to the white wire on the 12-3. Put the black and red on the traveler terminals on both switches, and the white on the 12-3 to common on the other switch.
Hope this helped, maybe TMI, have a great rest of your week!!
And, if I've mis-stated something, please correct me! Thank you.
 

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A "Handy Husband"
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I've done a lot of 3-way and 4-way lighting circuits. One thing that just sets off my OC is upside down 3-way switches. Yes, if one looks closely on the front of the switch yoke, just below where the mounting screw is, one will see "top" on one end.
So, if both switches are installed correctly, when the light is off, they will either both be down or both be up. If not installed correctly, when the light is off, one will be down and the other up.
If power and the light come into one of the switch boxes, then wire the neutrals together. Option 1 is to put the power on the switch. Use the 12-3 to go to the other switch. Put the black and red on the 2 terminals that are not marked "common". Put the white wire on "common". Wire the white wire from the 12-3 to the black wire for the light in the first box. In option 2, one may wire nut the power to the white wire in the 12-3 to the other switch, configure the other switch like I wrote above, and then put the black wire from the light on the first switch. I know, I know, a black and a white wired together. One could use the white in the 12-3 as one of the travelers, however the code says a white can be hot and used as an "identifier" in switch legs, and I do that so that electricians see that wiring configuration and it jumps out at them.
If the power comes into the light fixture, and there is a wire to the switch box, a 12-2, you will see what I'm talking about with the "identifier" business. The white would be hot and on the top part of the single pole switch if wired correctly. In this case to put in 2-3-ways, one would again put the white wire coming from the light fixture on the common of the first switch, and again wire nut the black wire from the light to the white wire on the 12-3. Put the black and red on the traveler terminals on both switches, and the white on the 12-3 to common on the other switch.
Hope this helped, maybe TMI, have a great rest of your week!!
And, if I've mis-stated something, please correct me! Thank you.
While that may be your preference, it is neither correct or incorrect.
 

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Joey is correct. Listen to him.
If you are not having to run to one switch to flip it a certain way to get the other to work, then its no problem.

Briefly, I will say what a switch does in the first place.
It takes a hot wire, and cuts it in half, before going up to the light. Its like a man standing there touching the wire together, and taking them apart again, making the light go off-on-off-on

well to make it so you can work that one light in two places, we can start all over. That guy has the hot wire, But this time, he takes it and splits it into being two wires, and he runs those two wires alllll the way to another guy at the end of the hallway.


that guy at the end of the hallway has the two wires as well as the one going to the light.

Nowthen, the first man takes his hot wire and attaches it to one of those two wires travelling down the hallway.

the guy down the hallway sees that and touches the other end to his wire heading to the light. the light is on.

the reverse is true too. If one of them disconnects one of those wires? the light will be off.

If you place this story in your mind's eye, with pictures, it will be easy to understand. If you just read it out, it wont. But Joe's right. Do as he says.
 

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I just installed four down lights in my living room with two three-way switches. I got a 12/3 running from one three way to the other three way.the switches are working fine except for one of the switches ... when I turn switch in the on position it shuts the lights off ..seems to be working backwards. is it just a simple reversing wires at that one switch? the red/ black on the 12/3??? thanks
Even if you swap the traveller, the next flip of the switch will have the lights on and one could be in the down position. To get it to work as you expect you would need to only use one of the two switches.
 

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I've done a lot of 3-way and 4-way lighting circuits. One thing that just sets off my OC is upside down 3-way switches. Yes, if one looks closely on the front of the switch yoke, just below where the mounting screw is, one will see "top" on one end.
So, if both switches are installed correctly, when the light is off, they will either both be down or both be up. If not installed correctly, when the light is off, one will be down and the other up.
The reason "top" appears on the yoke is they use the same yoke for single pole switches. If you put "top" to the bottom on both switches it will still work exactly the same. A real electrician ignores "top" altogether and simply wires the same orientation based on the position of the "common" terminal.

Further, add a 4-way switch into the circuit and you will see how insignificant "top" really is.
 
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