We are trying to set up comms with Kinetix Drives/AB motors through sercos ring during installation. On powering on, all drives show up 1, 2 &3 on 7 segment LEDs. After that one drive shows steady red in Drive status LED which indicates drive is faulted. But there is no error no. display on 7 segment display. Any ideas or suggestions to know what's wrong? we already checked wiring and optical fibres.