Electrical – Adding lights to a 3-way switched circuit

electricallightmultiway-switch

I currently have a circuit that goes like this:

Panel -> 3-Way switch -> 3-Way switch -> light

I have the wiring run through 2 additional boxes between the switches and I'd like to add lights in there to be controlled by both switches so that it looks like this:

Panel -> 3-Way -> Light -> Light -> 3-Way -> Light

I've got 12/3 running between the switches and the existing light, but I'm not sure if it's possible to add the lights in the middle, and if so, how to wire them in.

I can, if necessary, add 14/2 from the 3-Way -> light end of the chain, but, of course, would prefer to use my brilliantly planned ahead wiring (from 25 years ago).

I can add in a drawing of the exact wiring connections if that will be necessary.

Best Answer

Smart switches

Use smart switches for this. This makes the impossible easy.

Traditionally, you would need one cable with 4-5 active conductors plus ground. And all those must be in the same cable!! You cannot group two cables as a substitute for a cable with enough wires, ever. Nor can you use any #14 wire on a 20A circuit.

Here, we re-task white to be neutral, black to be always-hot, red to be switched-hot, and obtain a matching pair of master and remote 3-way smart switches that communicate wirelessly or via power line signaling.

Given the ease of this approach, doing traditional 3-ways is a waste of effort.