Siemens SINUMERIK 840D sl Function Manual page 1213

Procedure
Figure 16-1
Note
The speed arising from the configuration of the encoder limit frequency for the
resynchronization of the encoder (MD36302 $MA_ENC_FREQ_LOW) must be greater than
the position-control activation speed (MD35300 $MA_SPIND_POSCTRL_VELO).
Phase 1
Positioning from phase 1a:
The spindle is rotating at a higher speed than the encoder limit frequency. The spindle is not
synchronized.
Positioning from phase 1b:
The spindle is rotating at a lower speed than the encoder limit frequency. The spindle is
synchronized.
Note
If the position control is active, the speed can only amount to 90% of the maximum speed of
the spindle or the encoder limit frequency (10% control reserve required).
Positioning from phase 1c:
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Positioning from rotation
S1: Spindles
16.2 Modes
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