Siemens SINUMERIK 840D sl Function Manual page 1655

Figure 2-7
Note
An active reduction gear is not considered in the selection for the automatic gear stage
change.
Basic logic functions: Spindles (S1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Example for two "gear steps with overlapping speed ranges" for automatic gear step
change (M40)
Detailed Description
2.3 Configurable gear adaptation
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