[teamo]

I currently have a 3 way switch in the detached garage for the overhead lighting and a 3 way switch in the house so that I can shut off the lights from the house if I forget to turn them off. The wiring between the house and the garage is underground in pvc conduit with #14 THHN wiring. The conduit enters the garage and goes into a junction box where it is connected to nm cable that goes to the switch box. I am going to add a 4 way switch in between so that I can have another switch inside of the overhead door when I enter the garage that way. Instead of taking all of the wiring apart to rewire the 4 way switch into the middle of the run I was wondering if I can use 14/4 for the two sets of traveler wires from the junction box to the new location with the 4 way switch. The question is does this satisfy the requirements to have the entire circuit encased in the same cable or do I have to use two three wire cables and pass the common hot through the 4 way switch box?

 

[rjniles]

There is no requirement to run the hot through that switch.

 

[brric]

All that is needed is a three conductor cable from the existing garage switch to the new 3way switch location. The existing 3way in the garage becomes a 4way.

 

[joed]

What brric said.

 

[teamo]

"All that is needed is a three conductor cable from the existing garage switch to the new 3way switch location. The existing 3way in the garage becomes a 4way".

I was going to do it that way but the box that currently has the three way switch also has another switch and another circuit in it and it is maxed out. That is why I was looking to run the 4 way switch out from the junction box to avoid having to tear everything apart and change what is there.

 

[brric]

You don't tear any thing apart. The new cable gets attached to the wires on the old three way withe the common conductors wire nutted together.

Make a note of which wire is connected to the common on the garage 3way. Wire nut that wire to one of the wires running to the new 3 way and connect that wire to the common of the 3 way at the new location. That leaves you with two travelers at the new 3 way and 4 travelers for the 4 way at the old 3 way location.

 

[teamo]

I know how to wire the 4 way switch. Normally I run 2 three wire cables into the box in the middle of the run and wire nut the commons together with the travelers going to the 4 way switch. My question is about running only the travelers from the junction box in the middle of the run out to the 4 way switch. Would this satisfy the requirement to have the entire circuit encased in one cable? The tearing apart was what I was referring to when I said that the box with the current 3 way switch is maxed out. I would have to removed the cables running through there and reconfigure things to avoid over filling the box. If I was to add another 14/3 that would definitely put me over the limit of box fill calculations. I appreciate the help as always.