Siemens SINUMERIK 828D Function Manual page 1321

Function
If the function is activated, a predefined gear step is loaded automatically during transition to axis mode.
The gear step change is integrated into the M70 process and occurs after spindle deceleration and before the
loading of the servo parameter set with index 0 (note MD35590 $MA_PARAMSET_CHANGE_ENABLE!).
The typical dialog between NC and PLC which occurs during gear step changes is executed in a similar way to
programmed gear step changes (M41 ... M45).
Requirements
Gear step changes during transition to axis mode require general enabling of the gear step change via the
machine data:
MD35010 $MA_GEAR_STEP_CHANGE_ENABLE (assign parameters to the gear step change).
MD35090 $MA_NUM_GEAR_STEPS (number of gear steps set up)
Activation/Deactivation
The function is activated / deactivated via the machine data:
MD35014 $MA_GEAR_STEP_USED_IN_AXISMODE (gear step for axis mode in M70)
Value Meaning
0 No implicit gear step change occurs in M70. The current gear step is retained (default
setting!).
1 ... 5 A gear step change to gears 1 ... 5 occurs during the processing of M70.
Boundary conditions
Gear step change at fixed position (MD35010 $MA_GEAR_STEP_CHANGE_ENABLE = 2)
The "gear step change at fixed position" function is supported. The sequence in M70 is then extended by the time
it takes to position the spindle. The position is approached at the current gear step.
Transition to axis mode without programming M70
The control system detects the transition to axis mode automatically from the program sequence (see "Implicit
transition to axis mode [Page 1280]") and generates the requisite M70 sequence, including the gear step change,
within the control system.
Transition to axis mode with FC 18
Implicit gear step change is not supported in transition to axis mode with the FC 18 ("Start axis"). This requires
the right gear step to be engaged by the PLC application before switching to axis mode. The gear step change is
also possible with the FC 18 ("Start gear step change").
Change from axis mode to spindle mode
When changing from axis mode to spindle mode, the gear step loaded with M70 remains activated. The gear
stage which is activated in spindle mode prior to M70 is not automatically loaded again. The servo parameter set
is changed from parameter set 1 (index 0) to parameter sets 2 ... 6 (index 1 ... 5) to suit the gear step (with
MD35590 $MA_PARAMSET_CHANGE_ENABLE < 2).
Basic Functions
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
S1: Spindles
16.4 Configurable gear adaptation
1321