Siemens SINUMERIK 840D Function Manual page 780

S1: Spindles
18.4 Configurable gear adaptations
Second gear stage data set
The automatic gear stage change M40 can be extended by a second configurable gear stage
data set.
The second gear stage data set is used exclusively in connection with tapping without
compensation chuck (G331, G332) so that an effective adjustment of spindle speed and motor
torque can be achieved.
The activation is undertaken by setting the following bit for the master spindle:
MD35010 $MA_GEAR_STEP_CHANGE_ENABLE, Bit 5 = 1
The number of used gear stages of the second gear stage data set is defined with the machine
data:
MD35092 $MA_NUM_GEAR_STEPS2
The second gear stage block data set is deactivated if:
MD35092 $MA_NUM_GEAR_STEPS2 = 0 (basic setting)
The first gear stage data set then selects the gear stage when M40 is active.
Note
The number of gear stages in the second data set can vary from the first. If no appropriate gear
stage is found for a programmed speed for M40, then no gear stage change is carried out
(exceptions, see "M40: Automatic gear stage selection for speeds outside the configured
switching thresholds (Page 835)").
For more information about a typical program sequence in thread cutting without compensating
chuck G331/G332 see:
Further information:
Programming Manual - Fundamentals; Motion Commands
The gear stages 1 to 5 of the second gear stage data set can be parameterized via the following
machine data:
Machine data
MD35112 $MA_GEAR_STEP_MAX_VELO2[n]
MD35122 $MA_GEAR_STEP_MIN_VELO2[n]
MD35212 $MA_GEAR_STEP_POSCTRL_ACCEL2[n]
Note
The number of servo parameter sets concerning the mechanical factors remain unchanged.
Furthermore, five mechanical gear stages for the spindle and one for the axis operation can be
configured.
780
Meaning
Maximum speed for automatic gear stage
change
Minimum speed for automatic gear stage
change
Acceleration in position control mode
Function Manual, 06/2019, A5E47437747B AA
Axes and spindles