Description of the menu | 55
FRAKO | Operating Manual | Power Quality Controller – PQC
gency trip in response to the alarm in order to protect the power factor correction
system. This interrupts the automatic control function and deactivates (switches off)
all the control outputs. Automatic control remains deactivated for the duration of the
alarm plus a further 240 seconds. After this time, the PQC automatically begins to
control the system to achieve cos
φ
target
again.
– Alarm signal via Temperature
I/O output
If the PQC has the Temperature I/O option, the alarms can also be connected to
separate outputs. The assigned output remains switched on for the duration of the
alarm concerned (NO mode only).
– Alarm signal via
Modbus
If the PQC has the Modbus communications interface (RTU or TCP), the alarm
register can be read for all existing alarms. Please refer to the Modbus Specification
for further information
Note
The alarm setting options are describe in detail in the following sections. All
Alarm messages are listed in
.
6.3.4.2 Cos
φ
Alarm
Control band alarm: the PQC gives a cos
φ
alarm under the following conditions:
– The measured cos
φ
is more inductive than the control band and all the capaci-
tors are switched in. The PQC can therefore not switch in any more capacitance
to make cos
φ
more capacitive (see A).
– The measured cos
φ
is more capacitive than the control band and all the capac-
itors are switched out. The PQC can therefore not switch out any more capaci-
tance to make cos
φ
more inductive (see B and C).