ABB PQFM Instruction Manual page 193

above but the error phenomenon disappears faster than the time required
to generate a contactor opening command.
If the filter is OFF and an external critical error occurs, these errors are also
reported in the event log. As long as a critical fault condition exists (e.g.
permanent undervoltage on one phase) the display will show the message
'ACK. FAULT' and the filter will refuse to start; The 'Armed' indicator on the
PQF-Manager will be OFF and both the green and red main controller LEDs
will be OFF too.
In general the occurrence of transient faults is no problem for the proper
operation of the active filter. Only when an error becomes 'critical', a problem
may exist.
If 'ACK. FAULT' is present on the PQF-Manager display, look at the 'Armed' indicator (By
default mapped to the 4
main controller board to know whether the filter will restart automatically after
clearance of the problem or not.
- 'Armed' indicator/Green LED 2 ON: The filter waits for the problem to disappear and
then restarts automatically (unless the user acknowledges the fault).
- 'Armed' indicator/Green LED 2 OFF: The filter is permanently stopped and the
customer has to solve the problem, acknowledge the fault and restart the filter manually.
If the filter is in remote control operation and the message 'ACK. FAULT' is present on
the PQF-Manager, the fault can be acknowledged by sending a 'STOP' command by
remote control (low signal). Alternatively, the remote control functionality can be
disabled by disabling the corresponding digital input functionality. Then, the fault can
be acknowledged locally.
Refer to Chapter 11 for advanced troubleshooting of the filter.
th digital output of the PQF-Manager) or the green LED 2 on the
Manual Power Quality Filter PQFM ç Operating instructions 193