ABB PSTX Series Installation And Commissioning Manual page 80

7.3.2 Torque stop ramp
When using the Torque stop ramp, the output voltage to
the motor the torque follows a specified optimal curve
from the Step down level to end voltage during stop. The
Torque stop ramp makes the equipment that the motor
drives stop much softer than when using voltage ramp.
See Figure 7.5.
This can be especially useful in pump applications where
a sudden stop can cause water hammering and pressure
surges.
Configuration of the Torque stop ramp with these
7
parameters:
Parameter
02.02 Stop mode
02.05 Stop ramp end level
02.06 Stop ramp time
28.05 Step down level
28.08 Torque tune
28.09 Torque ctrl gain
28.10 Torque PI integration time
28.11 Torque slip
28.12 Torque diff
28.13 Torque filter time
80 Functions | Installation and commissioning manual |
Figure 7.5
Torque stop ramp
Description
Set to Torque ramp.
Sets the level from where the stop ramp ends and
the power to the motor is cut(voltage level for Voltage
stop and torque level for Torque stop.
Sets the time it takes for the voltage to come at end
level.
Sets the level from where the stop ramp initiates.
Sets the adjustment of resistive losses.
Sets the speed of the voltage regulator during torque
start and stop. It seldom needs to be changed,
but if a dip occur in the torque curve during stop,
increasing this value might solve it.
Sets the integration time of PI controller.
Sets the slip difference from nominal to pull-out
torque in percentage.
Sets the maximum desired difference between
reference and actual torque in percentage.
Sets the Torque control filter time in seconds.
1SFC132081M0201
U
Stop Time
rpm
Stop Time
Setting range
No ramp,
Voltage ramp,
Torque ramp,
Dynamic brake
10 ... 99%
1 ... 120 s
10 ... 100%
0...1000%
0.01 ... 10
0.001 ... 10 s
0.1 ... 100%
0.1 ... 100%
0.01 ... 10 s
Default value
No ramp
30%
10 s
80%
100%
0.02
0.004 s
1.0%
2.0%
0.02 s