3-way setups - none match provided diagrams

I’m replacing 4 dumb 3-way switches with Inovelli Blue (VZM31-SN-10). I want to replace 1 of each pair, leaving a dumb switch on the other side. However, none of my existing wiring matches the Inovelli schematics.

  • 3-way w/ dumb switches and neutrals

My existing wiring appears to be very inconsistent:

Wiring advice appreciated! I don’t wish to blow up my new switches or house.

I’m not sure there’s enough info here to answer your question. Posting pictures would probably help.

From what you posted, the first three could be a basic “line in one box, load in the other” setup. The last one can’t function as a proper three way as illustrated.

Do you have neutrals? There aren’t any in the illustration, but I’m pretty sure they are required for 3-way dumb installations.

Also, with 3-way dumb installations, I don’t think you have a choice about which box gets the smart switch. I believe the smart switch has to be in the box with the line.


  • I could post dark photos of paint-covered wires but not sure that’s better than the drawings
  • Yes I have neutrals available in each box
  • You’re right that #4 doesn’t work properly - it can turn on/off but when light is on one switch does nothing.
  • Don’t all of these switches have both line and load (the 2 blacks)? Still not clear on how to wire the Inovellis.

Line is the wire bringing the power in. Load refers to the wire going to the light.

For three ways with line in one box and load in another, one switch will have the line and two travelers. The other will have two travelers and the load. The wire colors don’t necessarily identify which is which. Red and black can be used for any hot wire. (And in older houses, white was often used for a switched hot or a traveler.)

Your picture shows four way switches. It is possible to wire up four ways to work as three ways. But if your switches are actually three ways, there is probably one black screw and two gold. The one going to the black screw will be the line or load, and the ones on the gold screws will be the travelers.

You’ll have to use a testing tool, such as a multimeter or non contact voltage tester to identify which box has the line.