Siemens Sinamics s120 Commissioning Manual page 231

Fine adjustment
1. The fine adjustment is started when the motor rotates with p1905 = 90.
The measurement takes approx.1 minute. The actual steps of the fine encoder
adjustment are displayed using alarm A07976. During the measurement, the difference
between the encoder and the EMF model is determined. The fine adjustment can also be
carried out in no-load operation (idle operation).
Note
Maintain the minimum motor speed
During the rotating measurement, the motor speed must exceed 40% of the rated speed.
The torque must remain below half of the rated torque.
The parameter setting p1905 = 0 is made automatically at the end of the measurement,
which completes the fine adjustment. An additional alarm informs you that the result from
p0431 will be written to the RAM at the next pulse inhibit.
2. To back up the new values, perform a "RAM to ROM" after the adjustment.
The adjustment result is also valid if, when the plant starts, the motor is driven by other
motors in the group of motors through the material web coupling. By correctly evaluating
the encoder, the Control Unit identifies the pole position and speed of the motor.
Note
1FW4 permanent-magnet synchronous motors
1FW4 motors are optimized for operation with this function. When commissioning with the
STARTER commissioning tool, all of the required data are automatically transferred to
the Control Unit.
STARTER Commissioning Manual
Commissioning Manual, (IH1), 07/2016, 6SL3097-4AF00-0BP5
3.16 Commissioning permanent-magnet synchronous motors
Commissioning
231