afee Start interlock 1 fault in ABB ACH180 drive indicates that a specific safety interlock condition has not been met, preventing the drive from starting.

This interlock is typically designed to protect the motor, the drive itself, or other connected equipment from potential damage or hazards.

1. Check the signal source selected for parameter 20.41 Start interlock 1.
2. If you are not using this parameter then change parameter value "20.41" to 1.