ABB PQFS Installation, Operation And Maintenance Instructions page 60

Table 24 shows the status of the alarm contacts for different operation modes of the
filter.
Table 24: Status of the alarm contacts for different filter operation modes
Filter state
Disconnected from the
supply
Filter (auxiliaries)
connected to the supply,
no error present
Filter (auxiliaries)
connected to the supply,
error appears
Filter (auxiliaries)
connected to the supply,
error disappears
Figure 42 shows an example of an alarm contact cabling scheme using the NC alarm
contact. Using this scheme the bulb B will be on when the power supply to the filter is
interrupted or the filter trips due to an error. Otherwise the bulb will be off.
Figure 42: Alarm bulb cabling scheme using the NC alarm contact on
When the filter system consists of multiple master-units and an alarm contact is needed
to signal when the complete system is off, then the NC alarm contacts of all the master
units have to be cabled in series. An example is given in
60 Electrical design and installation  Manual Power Quality Filter PQFS
Normally open alarm
contact state
Open
Closed
Opens when error
present for 3 minutes
Otherwise, remains
closed
When open before,
closes when error
disappears
When closed before,
remains closed
PQF-Manager
15
Alarm NO
(a)
outputs
16
NC
(a)
17
Remark:
(a)
Right hand terminal block when looking from rear, counting from top to
the PQF-Manager
Normally closed alarm contact state
Closed
Open
Closes when error present for 3
minutes
Otherwise, remains open
When closed before, opens when error
disappears
When open before, remains open
230 Vac
external
power
supply
External bulb
alarm indicator
B
Figure 43 for 2 master filters.