Connecting Came BPT AS C/251 to Ring Intercom

Good morning, I would need help on how to connect Ring Intercom to my Came BPT AS C/251 intercom. I have contacted email support but they have not yet been able to tell me how to connect the cables to my intercom, I only got a positive response in terms of compatibility.

On the official guides my intercom is not listed.

In my intercom there are 4 incoming cables and they connect to numbers 6-7-8-9

Thank you for your help!

6-7-8-9 is quite odd - is the front panel/intercom system a CAME/BPT System 200? Most BPT System 200 compatible handsets are wired 1-2-3-4 (old scheme) or 5-7-8-9 (new scheme).

This site has useful conversion guides for a number of CAME/BPT handsets, although unfortunately it doesn’t include a C/251.

Apparently the YC/251 is compatible with the C/251 and also the C/200 and E/200.

E/200, C/200 and later AGT A200 handsets are all compatible with each other, and definitely work with Ring Intercom.

Try moving the wire currently in 6 to 5, and configure the Ring Intercom for a C/200 aka AGT A200?