Help to install Operner for FERMAX VDS BUS 3 wires

Hi Nuki Team,

I have a home intercom operating on a 3-wire Fermax VDS BUS (+, -, L), but I am having difficulty installing the opener, although it is supposed to be compatible. I am contacting you for help in successfully completing this installation. I followed the instructions for wiring with or without bell, but I am still stuck at the same step: the device cannot register the opening signal. More precisely, the application remains stuck at the “operate the door opener” action (Voir PJ)

For your information, I have a Wibox system installed in parallel which works perfectly, but I want to replace it with the opener.

The nominal operation is as follows: I must ring from the street panel to answer the apartment’s intercom, when I pick up intercom, which allows the connection between the two devices to be established. Once the connection is established, I have to press the button to open the door. The intercom is a Fermax 3390 Loft Classic VDS.

Depending on the different wiring, the opener manages to detect when the connection is established manually, but it does not manage to recognize the doorbell signal and initiate the opening.

What advice could you give me for a successful installation?