why two wire dimmer and three wire switch?

[Alexander]

Why is that difference? I want to install some Duwi switches, but there aren't any neutral wires in the box. I would almost buy only Duwi dimmers, because it's a two wire system.

Alexander

[William.abbo]

Because the switches use 'hard' contacts, and when a contact is open in a 2-wire environment there is no supply-power for the electronics in the switch. Be carefull whith using a dimmer instead, they can only handle resistive loads (exept the Merten).