Siemens Sinamics CU240D-2 DP Operating Instructions Manual page 206

Advanced commissioning
6.15 Motor control
If you use encoderless vector control with a pulling load, then the following settings are
required:
● Set the following parameters:
● When opening the motor holding brake, enter a speed setpoint > 0.
For speed setpoint = 0, and with the motor holding brake open, the load drops because
the induction motor rotates with the slip frequency as a result of the pulling load.
● Set the ramp-up and ramp-down times ≤ 10 s in the ramp-function generator.
● If, in quick commissioning, you have selected application class Dynamic Drive Control
then set p0502 = 1 (technological application: dynamic starting or reversing).
204
Par. Explanation
p1750 Motor model configuration
Bit 07 = 1
p1610 Static torque setpoint (encoderless) (Factory setting: 50 %)
Set a value which is higher than the maximum load torque that occurs.
Use speed switchover limits that are less sensitive to external effects
Operating Instructions, 04/2018, FW V4.9 SP10, A5E34262100B AF
Converter with the control units CU240D-2