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KFU 2-/4-
188
Operation mode Overvoltage control,
Voltage controller:
Parameter
Operation mode
670 = 1
Ud
Ud, f
681
f
t
421 or 423
680
Overvoltage controller active
The overvoltage controller prevents a switch-off of the frequency inverter in generator
operation. The reduction of the drive speed by a ramp gradient selected via the pa-
rameter
Deceleration Clockwise
421
or
Deceleration Anticlockwise
423
can lead to
an overvoltage in the DC link. If the voltage exceeds the figure set by the parameter
Reference DC link limitation
680
, the deceleration is reduced in such a way that the
DC link voltage is regulated to the set value. If the DC link voltage cannot be regu-
lated to the set reference value by the reduction of the deceleration, the deceleration
is stopped and the output frequency raised. The output frequency is calculated by
addition of the parameter value
Max. Frequency Rise
681
to the frequency at the
operating point of the controller intervention.
Parameter
Settings
No.
Description
KFU
Min.
Max.
Fact. sett.
2-
225
387.5
Ud = 380 V
680 Reference DC link limitation
4-
425
770
Ud = 760 V
681 Max. Frequency Rise
2-/4-
0.00 Hz
999.99 Hz
10.00 Hz