# 3-Way Switch Wiring Confusion?

Discussion in 'Electrical and Wiring' started by savatreatabvr, Oct 22, 2013.

1. Oct 22, 2013

### savatreatabvr

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Ok, I'm not an idiot, well I did lose some brain cells back in the day but I can't seem to grasp the 3-way switch wiring concept. I know I need a 14/3 between the switches but there are so many different schematics and diagrams on the web eventually they all start looking the same. Can someone help me out with a basic, simple diagram for hooking up two 3-way switches to three ceiling lights from existing power?

2. Oct 22, 2013

### CallMeVilla

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You are probably confused by the need for traveler wires. It is not that difficult. The key is the black screw which either brings power from the main panel or sends power to the light. Once you do it, you will never have that confusion again.

This video is a lot better on detail and energy ...

Now ... GO wire that bad boy!

Last edited: Oct 22, 2013
3. Oct 22, 2013

### nealtw

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So lets narrow it down a little.
Does the power first come to a switch or a light fixture?
Which would be easier. Run a 3 wire between the two switches and a seperate 2 wire to the lights, or run a 3wire to the lights and down to the other switch.
Any way you do it you just run two wire from the first light to the rest of the lights.
Once you answer these questions finding the right diagram will be easy.

4. Oct 22, 2013

### bud16415

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I tried to give my take on this the other day but wasn’t successful. Before you can wire such a circuit you have to grasp the concept of how a 3 way switch works. Once you grasp that concept the circuit should explain itself. All the connect this to this and that and travelers etc won’t make the light in your head come on and that’s the first light that needs to light up.

Villa’s first youtube shows it pretty clearly.

A 3way switch isn’t an on and off switch it is a selector switch commonly called a single pole double throw. In schematic form it looks like a Y connection where power comes in the bottom of the Y and has the choice to go out one of the two tops of the Y. it never gets shut off just gets directed that’s why we use two of the switches together, connected at the tops of the Y. Think of a 3 way switch as an A/B selector switch. With two of them wired as such, A wired to A and B wired to B. When both A’s are on you have an electrical path or when both B’s are on you have a path. A&B or B&A you have no path. The wires between A,A and B,B are what they call travelers.

If you are at one end of the hall and the lights are off it means the switches are A,B or B,A and when you flip that switch it makes it A,A or B,B and that’s a complete circuit and the light comes on. When you get to the other end of the hallway you flip the other switch and it makes the A,B or B,A condition again and the light goes out.

Here is the symbol for a normal light switch a SPST single pole single throw and also a SPDT single pole double throw such as a 3 way switch.
http://www.electrostudy.com/2012/05/toggle-switch-spst-switch-and-spdt.html

Here is how they work together as a pair.
http://en.wikipedia.org/wiki/Multiway_switching

Hope this helps.

5. Oct 22, 2013

### JoeD

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Since you have three fixtures this is the best option. Just add two more fixtures connected to the first one.
Do not try and put three fixtures between the switches. That would require a four wire cable.

6. Oct 22, 2013

### CallMeVilla

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Nice thought Joe ... I modified your pic to reflect the arrangement for one more fixture and it could just as easily be three or more ...

7. Oct 24, 2013

### savatreatabvr

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FINALLY GOT IT!!! In a 3-way circuit as long as there is a incoming hot connected to the black screw on one 3-way switch and a black outgoing hot to the load and the red & white connected to the travelers it will work. And of course the incoming white connected to the outgoing white. My next task is getting the completed wiring in the box to look decent, it's definitely a skill all in it's own!

nealtw likes this.
8. Oct 24, 2013

### CallMeVilla

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In your excitement, you said "... and the red and white connected to the travelers ..." The WHITE is the neutral !

Incoming hot is BLACK
Incoming neutral is WHITE
Incoming ground is bare or GREEN
Travelers are RED and BLACK between switches
Outgoing to light is BLACK.
The neutral is WHITE, connecting ONLY to WHITE.

NOW you GOT IT!

9. Oct 26, 2013

### savatreatabvr

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LOL! Yep I'm an IDIOT! After blowing up a \$30 dimmer switch I decided I'm going to figure this out if it kills me! I went to Home Depot thinking I'll pick up another dimmer but left with 2. I didn't know until I got home that those Bozos recommended the (\$30 Lutron Maestro MACL-153M), those dimmer switches have a BLUE screw, ok now I'm really confused. Below is a diagram I drew hoping somebody can fill in the blanks before I blow up more dimmers!

10. Oct 26, 2013

### CallMeVilla

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You are dealing with a multi-location dimmer option now ... Did not see that in the beginning. Here is the Lutron instructional ... Notice the DIFFERENT dimmers being used.

Is she happy yet?

11. Oct 27, 2013

### savatreatabvr

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The video didn't help much but I got it anyways and yes SHE'S HAPPY! I was trying to use one of the 14/3 wires to power the 2nd switch, so I just ran a new 12/2 from an end of line outlet to the 2nd switch which is now the 1st switch, lol, and made the original 1st switch into the 2nd one. Kinda just reversed everything and added power to the original 2nd switch! It all works perfectly! I sincerely appreciate everyone's input because it made me realize how ignorant I can be and how simple the 3-way circuit is! Now I'm going to add a 3-way dimmer to my kitchen recessed lighting. It already has a dimmer but she wants another one at the other end of the kitchen. I ran a 14/3 between the old dimmer and the new location last week so wish me luck!

12. Nov 3, 2013

### savatreatabvr

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I got it, I got it, I got it! How stupid of me to not see something so simple. One 3-way switch gets power on the black, the other 3-way switch gets connected to the light and it doesn't matter which ones the (TRAVELERS) connect too, vise versa! It's still easier on paper than it is standing in front of a box with a bunch of wires in it, lol!

13. Dec 9, 2013

### ohmy

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Multi location dimmers are easy to install once you get this one concept. The blue is a signal wire not a switched wire. When you are retrofiting with multi location dimmers its easiest just to undue all the taps in the box related to the original 3way switch and start from scratch. The instructions for Lutrons Electronic switches try to avoid opening and taps and so they are unnecessarily confusing.

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