ABB ACS880-31 Hardware

This fault indicates a discrepancy in the status of the two Safe Torque Off (STO) channels. The drive's diagnostics have detected that the STO channels are not in the same state, or that STO was attempted to be activated in a non-redundant manner (e.g., only one channel activated). This prevents the STO safety function from operating correctly and will cause the drive to trip, leading to an uncontrolled stop or inability to start, posing a safety risk if machine motion is not reliably prevented.

This fault indicates a discrepancy in the status of the two Safe Torque Off (STO) channels. The drive's diagnostics have detected that the STO channels are not in the same state, or that STO was attempted to be activated in a non-redundant manner (e.g., only one channel activated). This prevents the STO safety function from operating correctly and will cause the drive to trip, leading to an uncontrolled stop or inability to start, posing a safety risk if machine motion is not reliably prevented.