Determining The Spindle Gear Stage - Siemens SINUMERIK 840D Function Manual

S1: Spindles
18.4 Configurable gear adaptations
5. N05 (part program, refer below) is executed:
The gear stage is changed to gear stage 1.
From the NC:
– the following NC/PLC-interface signal is set:
– the setpoint gear stage 1 is signaled to the PLC:
6. Mechanical gear stage change, acknowledgement
If the gear stage is selected, then from the PLC:
– the following NC/PLC-interface signal is set:
– Actual gear stage 1 signaled to the NC:
7. N80 is executed:
Due to the optimization of the gear stage change frequency in the part program, the gear
stage is not changed.
Part program:
Program code
N05 M41
...
N80 M41
Configuring data for spindle 1 (AX5):
MD35010 $MA_GEAR_STEP_CHANGE_ENABLE[AX5] = 1 (enable gear stage change)
18.4.3

Determining the spindle gear stage

The actual stage of a spindle can be read using system variables:
● For the display in the user interface, in synchronized actions or with a preprocessing stop in
the part program via the system variables:
$VC_SGEAR[<n>]
788
DB31, ... DBX82.3 (change over gear stage)
DB31, ... DBX82.0 = 1
DB31, ... DBX82.1 = 0
DB31, ... DBX82.2 = 0
DB31, ... DBX16.3 (gear is changed)
DB31, ... DBX16.0 = 1
DB31, ... DBX16.1 = 0
DB31, ... DBX16.2 = 0
Comment
; Select 1st gear stage
; No gear stage change, if the 1st gear stage is selected.
Currently selected spindle gear stage
$VC_SGEAR reads the actual gear stage signaled from the
PLC.
Value range: 0 ... 5
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA