Siemens SINUMERIK 840Di Function Manual page 1522

Detailed Description
2.1 Spindle modes
Fig. 2-3
Phase 1
Case 1: Spindle not synchronized
The programming of SPOS, M19 or SPOSA accelerates the spindle with the acceleration from
machine data:
MD35200 $MA_GEAR_STEP_POSCTRL_ACCEL (Acceleration in positioning mode).
The direction of rotation is defined in machine data:
MD35350 $MA_SPIND_POSITIONING_DIR (Direction of rotation when positioning from
standstill).
Exception:
If ACN, ACP, IC is used for positioning, the programmed direction of travel is activated.
The spindle is synchronized with the next zero mark of the spindle position actual-value
encoder and switches to position control mode.
2-18
Positioning with stationary spindle
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Spindles (S1)