Siemens SINAMICS V90 Operating Instructions Manual page 189

External reference cam (signal REF) and encoder zero mark (p29240=1)
The referencing is triggered by signal SREF. After that, the servo motor accelerates to the
speed specified in p2605 to find the reference cam. The direction (CW or CCW) for
searching the reference cam is defined by p2604. When the reference cam is reached
(signal REF: 0→1), the servo motor decelerates to standstill. After that, the servo motor
accelerates again to the speed specified in p2608 and the running direction is opposite to the
direction defined by p2604. Then the signal REF should be switched off (1→0). When the
servo motor reaches the first zero mark, it starts to travel towards the reference point defined
in p2600 with the speed specified in p2611. When the servo motor reaches the reference
point (p2599), the signal REFOK is output. Switch off the signal SREF (1→0) and the
referencing finishes successfully.
The whole process is shown in the diagram below:
SINAMICS V90, SIMOTICS S-1FL6
Operating Instructions, 09/2016, A5E36037884-002
Control functions
7.4 Internal position control (IPos)
189