in my home there is an 2 Wire Intercom from this Shop
If no one is ringing there is no Voltage on my Intercom.
I was able to trigger my door opener because i have extra wires from my flat to the door opener only for nuki. I have to connect the blue to the opener and the purple to 12V. My Intercom on the front door have 12v and GND wire directly to the door opener.
But I am not able to get the ring decetion to work.