Wiring help for 3 way dimmer config

Ok this is my first time installing any of these switches.

I got a GE Z-Wave Plus dimmer and add on.

in this photo is the current dimmer switch

In this photo the switch on the right is the 3way on/off switch for the dimmer. The switch on the left controls the porch light.

So these are my guesses but I wanted to ask you smart people before I connect everything:

On main dimmer:
Connect the black wire to the Load on the new dimmer (this is the only one I’m confident in)
Connect red/red wire to the Line on the new dimmer
Connect the black/red to the Neutral
Green to ground (confident here too lol)

I think I’ll stop guessing at this point because I’m pretty confused.

On the addon I have no idea because it is in line with that other switch.

Any help is greatly appreciated!

Have a look at this thread, it should help get you going:


I agree, that thread is a great resource.

I had minimal knowledge of home electrical wiring before I got interested in ST and changing out some of my old switches. This community has been super helpful, and I read a fair amount online from other sources too. I’ve replaced a few switches and added smart relays to some of my fixtures.

I can’t emphasize enough (which is mentioned in that linked thread), buy a multi meter and learn how to use it. If you’re not 100% sure what each wire is in all switch boxes (which is what the multimeter is for), then seriously consider hiring a pro to do it for you.


I have a multimeter. I got everything working. I found a youtube video of someone with a very similar setup and pretty much matched it.