Siemens SINUMERIK 840D sl Function Manual page 1637

DB31, ...
DBX16.0 - DBX16.2 Actual gear stage A to C
Edge evaluation: Yes
Signal state 1 If the new gear stage is engaged, the PLC user program sets the interface signals:
(statusdriven) DB31, ... DBX16.2 - DBX16.0 (actual gear stage A to C)
and
DB31, ... DBX16.3 (gear is changed over).
This signals the NCK that the correct gear stage has been successfully engaged.
The gear change is considered to have been completed (spindle oscillation mode is deselected), the
spindle accelerates in the new gear stage to the last programmed spindle speed and the next block
in the parts program can be executed.
The actual gear stage is output in coded format.
For each of the 5 gear stages, there is one set of parameters assigned as follows:
Special cases, If the PLC user reports back to the NCK with a different actual gear stage than issued by the NCK as
errors, ...... the setpoint gear stage, the gear change is still considered to have been successfully completed and
the actual gear stage A to C is activated.
Corresponding to ... DB31, ... DBX82.0 - DBX82.2 (setpoint gear stage A to C)
DB31, ... DBX82.3 (change over gear stage)
DB31, ... DBX16.3 (gear is changed)
DB31, ... DBX18.5 (oscillation speed)
Parameter sets for gear stages
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Signal(s) updated: Cyclically
Z1: NC/PLC interface signals
19.11 Spindles (S1)
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