ABB PQFM - Page 81

Manual Power Quality Filter PQFM  Electrical design and installation 81
Table 30: List of possible alarm conditions that may trigger the alarm/digital outputs
Alarm condition
Criteria to be fulfilled before contact is activated
Supply voltage (RMS) unacceptably
high
Vrms_m
ax > 110% Vn
ominal
Supply voltage (RMS) unacceptably
low
Vrms_min < 90% Vnominal
One of the phases of the supply is
missing
Vrms_min < 60% Vnominal
Network imbalance unacceptably high
Vimbalance > 2%
Frequency variation unacceptably
high
Frequency var
iation > 20%/s
PQFM DC bus voltage unacceptably
high
Vdc > 105% Vdc_max_allowed
PQFM internal preload error
DC capacitor voltage rise too low in preload phase or
the DC capacitors could not be preloaded in an
acceptable time.
PQFM overcurrent fault
Int
ernal current higher than allowed
PQFM ground fault
Internal ground current higher than allowed
PQFM IGBT fault
IGBT hardware reports internal permanent error
PQFM IGBT overtemperature
IGBT hardware reports internal overtemperature
Control board temper
ature too high
Internal control board temperature probe reports
too high temperature
PQFM internal power supply fault
Internal control voltage too low or not present
PQFM control board fault
Internal control board reports an error
PQFM unit down (i.e. n
ot operational
due to error)
Any of the units in a multi
-
unit arrangement is not
running although the start-command has been given.
Remark: the alarm trigger levels cannot be changed by the user.
For cabling the digital output contacts as alarm contact, the same approach as shown
in Figure 62 can be adopted. Note however that the following behavior will result:
− The voltage applied to the external monitoring device will be low when:
o The filter is disconnected from the supply or when there is no error.
− The voltage applied to the external monitoring device will be high when:
o The predefined error is present for the predefined time (minimum 180s)
AND
o The external 24 Vdc power supply is in working order.
The different electrical characteristics of the digital output contacts compared to the
alarm contact characteristics must be respected. Note also that all digital outputs have
the same common which is located at the pins 1 and 2 of the right hand terminal of the
PQF-Manager (rear view, counting from top to bottom). This is clearly indicated in
Figure 57 above.