Siemens SINUMERIK 840D sl Function Manual page 1559

2.4.2 Phase 1: Traversing to the reference cam
Phase 1: Graphic representation
Figure 2-2 Phase 1: Traversing to the reference cam
Phase 1: Start
For information on starting reference point approach, refer to "Axis-specific referencing" and
"Channel-specific referencing."
Phase 1: Sequence
In phase 1, depending on the position of the machine axis with reference to the homing cam,
we distinguish between three cases:
1. The machine axis is positioned before the reference cam
2. The machine axis is positioned on the reference cam
3. The machine axis has no reference cam
Case 1: The machine axis is positioned before the reference cam
After the start of reference point approach, the machine axis is accelerated in the
parameterized direction and to the parameterized reference point approach velocity :
MD34010 $MA_REFP_CAM_DIR_IS_MINUS (Reference point approach in minus direction)
Basic logic functions: Reference Point Approach (R1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
2.4 Referencing with incremental measurement systems
Detailed description
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