Siemens SINAMICS G120C Operating Instructions Manual page 210

Advanced commissioning
6.5 Motor control
Recording a friction characteristic
After basic commissioning, the inverter sets the speeds of the intermediate points to values
suitable for the rated speed of the motor. The frictional torque of all intermediate points is still
equal to zero. On request, the inverter records the friction characteristic: The inverter
accelerates the motor step by step up to the rated speed, measures the frictional torque und
writes the frictional torque into the intermediate points of the friction characteristic.
Requirement
The motor is permitted to accelerate up to the rated speed without endangering persons or
property.
Procedure
To record the friction characteristic, proceed as follows:
1. Set P3845 = 1: The inverter accelerates the motor successively in both directions of
rotation and averages the measurement results of the positive and negative directions.
2. Switch on the motor (ON/OFF1 = 1).
3. The inverter accelerates the motor.
During measurement, the inverter signals the warning A07961.
When the inverter has determined all the intermediate points of the friction characteristic
without fault code F07963, the inverter stops the motor.
You have recorded the friction characteristic.
Interconnect the precontrol of the speed controller with the frictional torque
206
To interconnect the precontrol of the speed
controller with the frictional torque, set p1513 =
r3841 (frictional torque = additional torque 2).
You will find additional information in function
diagram 6060 of the List Manual.
Operating Instructions, 07/2015, FW V4.7 SP3, A5E34263257B AC
SINAMICS G120C converter