Stop Ramp Time - ABB PSE 18 Installation And Commissioning Manual

Figure 7.6: Stop Ramp Time parameter
displayed
U
rpm
Figure 7.7: The function of Stop Ramp Time

7.5.3 Stop Ramp Time

The Stop Ramp Time parameter allows for tuning of the time for the stop ramp to
reach the End Voltage from Top of Ramp (TOR).
When a stop signal is given the PSE Softstarter performs a stop ramp by control-
ling the output voltage to the motor so that the voltage is decreased linearly from
full voltage to the end voltage level. Since the torque depends on both the voltage
and the current, the torque curve does not always follow the voltage curve. This
has the effect that the torque curve will not decrease linearly. If parameter Torque
Control during stop is set to OFF, will a voltage ramp be performed during the
stop ramp. The voltage and RPM of the motor will follow the graph in figure 7.7. If
a torque curve with linear decrease is preferred, set Torque Control during stop to
On. See chapter 7.5.7.
This parameter shall be set to OFF for applications with a big flywheel mass
involved.
Display
The time set in Stop Ramp Time is also the setting for the time in Torque
Control Stop, if this parameter is enabled.
Softstarters Type PSE18...PSE370 Installation and commissioning manual 1SFC132057M0201
Default value Setting range
OFF 0-30 s
Description
Setting time for voltage
controlled and torque
controlled, stop
ramps
Chapter 7 61