Rockwell Automation 7763 Medium Voltage OneGear SMC Flex Motor Controller (10-15 kV) - Manual (Page 22)

22 Rockwell Automation Publication 7760-UM001D-EN-P - October 2014
Chapter 1 Product Overview
Starting Modes Soft Start
This mode has the most general application. The motor is given an initial torque
setting, which is user-adjustable from 0…90% of locked-rotor torque. From the
initial torque level, the output voltage to the motor is steplessly increased during
the acceleration ramp time. The acceleration ramp time is user-adjustable from
0…30 seconds. Once the MV SMC Flex controller senses that the motor has
reached the up-to-speed condition during the voltage ramp operation, the output
voltage automatically switches to full voltage, and the bypass contactor is closed.
Figure 8 - Soft Start
100%
Percent
Voltage
Start Run
Time (Seconds)
Initial
Torque