I want to add a remote switch to one of our lights which already has three manual switches. The way the wiring is set up is that in the wallbox where the remote switch is going to be installed I don’t have the neutral line that belongs to the light circuit, only the power line. There is a different neutral line from a different circuit but I cannot use it with switches such as the one from Fibaro because the earth leakage circuit breaker will go off if I take the power from one circuit and the neutral from the other. Therefore I’m looking for a switch that either has two complete separate input for the device power and the switching circuit or a switch that doesn’t need external power at all. Do such devices exist?
I think, you can use a Shelly 1 for this. That has separated power in and a dry contact switch.