Cause : START INHIBIT comes when safe torque off function has been activated while drive was stopped or optional start inhibit hardware logic is activated.

The code FF7A in your ABB ACS800 drive indicates a fault related to the Start Inhibit function. This function essentially prevents the motor from starting under certain conditions. An FF7A fault signifies that the drive has detected an active Start Inhibit signal or condition.

1. Close Safe torque off function switch.
2. If switch is closed and warning is still active, check power supply at ASTO board input terminals.
3. Replace ASTO board. Or: Check start inhibit circuit (AGPS board).