Cause : MOD CHOKE TEMPERATURE comes when overtemperature in choke of liquid cooled R8i inverter module. This fault signifies that the choke's temperature has exceeded the acceptable operating limits.

The fault code FF89 in your ABB ACS800 drive indicates an issue with the temperature of the choke in a liquid-cooled R8i inverter module. The choke is a passive component that limits high-frequency current spikes within the inverter circuit.

1. Check inverter fan.
2. Check ambient temperature.
3. Check liquid cooling system.