202 Troubleshooting guide
Manual Power Quality Filter PQFS
Fault message
Cause
What to do
Unbalanced
supply
The supply network imbalance
is out of range.
−
Measure the three line
voltages and check if they
are within limits including
the imbalance limit.
−
Measure the line voltages
(e.g. voltmeter) and
compare them with the line
voltages given by the filter
(PQF-Manager or PQ-Link).
−
Ensure that the AC voltage is
properly measured. Do the
checks discussed for the
‘Loss of phase’ fault.
−
Check the earth of the unit.
Undervoltage
RMS
The RMS value of the supply
voltage measured with the AC
voltage measurement board is
lower than the acceptable
maximum value.
−
Measure the three line
voltages and check if they
are within limits.
−
Measure the line voltages
(e.g. voltmeter) and
compare them with the line
voltages given by the filter
(PQF-Manager or PQ-Link).
−
Ensure that the AC voltage is
properly measured. Do the
checks discussed for the
‘Loss of phase’ fault.
Unstable mains
frequ.
The network frequency is
varying too fast.
−
Measure the network
frequency and its variation,
and check if they are within
limits.
−
Check the phase rotation
(only in case of modification
at the installation).
−
Ensure that the AC voltage is
properly measured. Do the
checks discussed for the
‘Loss of phase’ fault.
Wrong phase
rotation
The supply network feeding
the filter has the wrong phase
rotation.
−
Check the phase rotation of
the filter supply.
−
Measure the three line
voltages and check if they
are within limits.
−
Measure the line voltages
(e.g. voltmeter) and
compare them with the line
voltages given by the filter
(PQF-Manager or PQ-Link).
−
Check the AC voltage
measurement connectors