Siemens SINUMERIK 840D sl Function Manual page 1647

2.3 Configurable gear adaptation
2.3.1 Gear steps for spindles and gear step change
Why do we need gear steps?
Gear steps are used on spindles to step down the speed of revolution of the motor in order
to generate a high torque at low spindle speeds or to step up in order to maintain a high
speed.
No. of gear steps
5 gear steps can be configured for each spindle.
If the spindle motor is mounted to the spindle directly (1:1) or with a non-adjustable gear
ratio,
machine data:
MD35010 $MA_GEAR_STEP_CHANGE_ENABLE
must be set to zero.
In this case, the 1st gear step is active. This is the default setting.
Selection of gear change type
Configuring machine data:
MD35010 $MA_GEAR_STEP_CHANGE_ENABLE (Gear step change is possible)
determines the gear step change type as follows:
0:
1:
2:
3:
5:
Requirement for a gear step change:
Activated by the NC by setting machine data:
MD35010 $MA_GEAR_STEP_CHANGE_ENABLEnot equal to 0
and by the part program at M40 with S... or M41...M45.
In principle, the gear step change is only performed, however, if the requested gear step is
not the same as the active gear step.
The following section explains who can request a gear step change and how it is triggered,
initiated and completed.
Basic logic functions: Spindles (S1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Spindle motor installed directly (1:1) or with a nonvariable transmission ratio.
Spindle motor with up to 5 gear steps.
The gear step change is executed in oscillation mode.
Spindle motor with up to 5 gear steps.
The gear step change is executed at the configured fixed position.
Gear step change protocol between NCK and PLC is simulated.
The second gear step data set is applied with G331/G332, e.g. for rigid tapping.
Detailed Description
2.3 Configurable gear adaptation
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