Referencing In Follow-Up Mode - Siemens SINUMERIK 840D Function Manual

R1: Referencing

10.8 Referencing in follow-up mode

Sequence
1. Initial situation: Both measuring systems are not referenced:
DB31, ... DBX60.4 = 0 (referenced/synchronized 1)
DB31, ... DBX60.5 = 0 (referenced/synchronized 2)
2. Referencing of the indirect measuring system according to the measuring system type:
DB31, ... DBX60.4 = 1 (referenced/synchronized 1)
DB31, ... DBX60.5 = 0 (referenced/synchronized 2)
3. Traversing of the machine axis across the parameterized number of reference marks.
This automatically references the direct measuring system:
DB31, ... DBX60.4 = 1 (referenced/synchronized 1)
DB31, ... DBX60.5 = 1 (referenced/synchronized 2)
10.8 Referencing in follow-up mode
Function
Incremental measuring systems and measuring systems with distance-coded reference marks
can be referenced even when the machine axis is in follow-up mode. Prerequisite for this is the
correct parameterization of the reference point approach according to the used measuring
system (see Section "Referencing with incremental measurement systems (Page 296)" and
"Referencing with distance-coded reference marks (Page 309)").
When referencing in follow-up mode the machine axis is moved not by the NC but by means of
an external travel motion over the encoder zero mark and the parameterized number of
distance-coded reference marks. The measuring system is referenced when the encoder zero
mark or parameterized number of distance-coded reference marks are detected.
Note
Reproducibility of the referencing result
In NC-guided reference point approach, reproducibility of the referencing result is ensured
through adherence to the assigned traverse velocities during the referencing operation. During
referencing in follow-up mode, responsibility for achieving reproducibility of the referencing
results lies with the machine manufacturer / user.
Unique zero mark
Referencing of an incremental measuring system is based on the explicit position of the
encoder zero mark relative to the overall traversing range of the machine axis.
Because the reference cam signal is not evaluated by the NC during referencing in follow-up
mode, unique identification of the reference point when referencing in follow-up mode will only
result with:
● Only one encoder zero mark in the traversing range of the machine axis.
● Linear measuring systems with distance-coded reference marks.
● Modulo rotary axes (absolute position within one revolution).
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Axes and spindles
Function Manual, 06/2019, A5E47437747B AA