Siemens SINUMERIK 840D sl Function Manual page 1599

Sequence of referencing operation (AUTOMATIC mode)
1. Switch to AUTOMATIC mode.
2. Start the part program.
3. Activate follow-up mode of machine axis:
4. Take into account activation of follow-up mode:
5. The referencing operation is started internally in the NC as soon as part program
6. External movement of machine axis across encoder zero mark or parameterized number
7. The measuring system is referenced after the encoder zero mark or the assigned number
8. The block change occurs after the referencing operation has been successfully
Aborting the reference operation
An active referencing operation can be aborted by:
• Deselecting follow-up mode
• NCK Reset
Response when measuring systems are already referenced
A measuring system that you have already referenced can be referenced again.
Basic logic functions: Reference Point Approach (R1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
DB31, ... DBX1.4 (follow-up mode) = 0
DB31, ... DBX2.1 (servo enable) = 0
DB31, ... DBX61.3 (follow-up mode active) = 1
instruction G74 is processed.
of distance-coded reference marks.
of distance-coded reference marks have been successfully detected:
DB31, ... DBX60.4 / 60.5 (referenced/synchronized 1/2) = 1
completed.
Detailed description
2.8 Referencing in followup mode
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