I've seen posts about going from a switch to a dimmer, but not the other way around. I originally thought I could read those and do the opposite, but it seems that there are many ways houses can be wired, and my particular setup doesn't match anything else I have seen.
I currently have a Z-Wave dimmer switch installed. It has two black wires coming out and one green. The black wires are supposed to go to either line and load.
My new Z-Wave 2way switch has load, line, neutral, and ground. I determined that load goes to my light, line goes to whatever is hot, and ground obviously goes to ground. I figured out which was hot by turning off the circuit at the breaker, disconnecting the switch, then turning it back on again and measuring the voltage. The black wire with the 120V is line, and the black wire without 120V must be the load.
Now my issue is with the neutral -- since it wasn't previously hooked up, there is a bundle of three wire wires in the box capped off. The problem is that I don't have three entry points to the switch. I could insert 2 of the 3 into the holes, and the strip some extra insulation off of the third and wrap it around the screw (and check to make sure the other two are still tight), or I could go get some solid core wire at the store and add a fourth white wire to the capped bundle, then run this fourth to the switch.
Ultimately, my question is, shouldn't all switches and outlets have a dedicated line back to the breaker box? If neutrals are tied together in boxes, doesn't this mean that there could be two circuits are sharing the neutral? And if this is the case, doesn't that mean that working in the box is inherently not safe if the other circuit is still live? Also, does this mean that I cannot simply pull one the three white wires from the bundle and hook it up to the switch, since that would separate it from the other two, and there might not be a path back to the breaker box for one of the circuits?