Fault Reaction Function; Parameter Settings; Hardware Settings - ABB ACS880 User Manual

14 Option description and instructions

Fault reaction function

Definition: A safety function requires a "fault reaction function" that attempts to initiate a
safe state if the safety function's diagnostics detect a fault within the hardware/software
that performs the safety function.
The fault reaction function of the POUS safety relay [A65] trips if it detects a failure (short
circuit between signals, open circuits, redundancy fault when the POUS switch is pressed)
in the safety circuit. The fault reaction function shifts the drive immediately into the safe
state by activating the STO function. The STO function is active until the fault has been
repaired. The POUS indication lamp is on until the fault has been repaired.
The STO function has its own internal fault diagnostics and fault reaction function.

Parameter settings

Note: ACS880 primary control program controls the inverter unit by default. There are
dedicated control boards for the supply and inverter units.
The supply unit parameter settings in the ACS880 supply control programs:
•
parameter 121.05 Emergency stop source is set to value Inactive.
For more information, see the firmware manuals.

Hardware settings

Appropriate hardware settings have been preset at the factory for the safety function.
The settings in the POUS safety relay [A65] are:
•
cross fault detection is set to value On,
•
reset is set to value Automatic.
Note: If the cross fault detection is not On, it decreases the fault diagnostics of the wiring.
For more information, see the circuit diagrams delivered with the drive.