ABB PQFM Instruction Manual page 205

A critical fault is a fault that after occurrence cannot be successfully
-
automatically cleared by the system within a reasonable time. The time frame
considered depends on the error type. If the fault is considered critical by the
system, the label 'Critical' will be shown in the event logging window. In
addition, the PQF item in the PQF-Manager 'Welcome' screen will display the
label 'ACK. FAULT. Note however that if the fault disappears fast, this label
disappears too.
Depending on the type of critical fault and the number of occurrences, the filter, when
running, may either:
- Stop (open the main contactor) and await user intervention. In this condition
the alarm contact of the PQF-Manager will switch on after a programmable
delay and the 'Armed' indicator will be OFF. The green LED on the main
controller board (Cf.
Table 12 item 18, LED 3). The user has to acknowledge the fault (with the PQF-
Manager via Modbus or via remote control) before the filter can be restarted.
By default, the 'Armed' indicator is associated with the fourth digital output
contact (cf. Table 9
top of the PQF-Manager display (Cf.
status of the digital output. Alternatively, the digital output considered can be
wired to monitor the 'Armed' indicator by distance (cf.
- Stop (open the main contactor) and restart automatically if the fault
disappears. If stopped, the alarm contact of the PQF-Manager will switch on
after a programmable delay and the 'Armed' indicator will be ON. The green
LED on the main controller board (Cf.
the red LED will be OFF (Cf.
before the fault disappears, the user may decide to give a filter stop command.
This is done by highlighting the 'PQF ACK. FAULT' item in the 'Welcome' menu
and selecting
and red LED on the main controller board (Cf.
will be OFF too.
Stop briefly without opening the main contactor and continue filtering when
-
the error has disappeared. This is essentially the same case as the one
described above but the error phenomenon disappears faster than the time
required to generate a main contactor opening command.
If the filter is OFF and a critical error occurs (e.g. network undervoltage), the errors
will also be 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.
Table 12 item 18, LED 2) will be off and the red LED on (Cf.
and Table 10). The digital output contact monitor at the
Figure 69
Table 12
Table 12 item 18, LED 3). If it takes a long time
. After this, the 'Armed' indicator (a) will be OFF. The green
Manual Power Quality Filter PQFM ç Troubleshooting guide 205
item 3) can be used to check the
Section 6.12.4)
item 18, LED 2) will be ON and
Table 12 item 18, LEDs 2 and 3)