Siemens SINUMERIK 840D sl Function Manual page 242

Functions
2.8 Acceleration with active jerk limitation (SOFT/SOFTA) (axis-specific)
2.8.2 Activation
2.8.2.1 Parameterization
Function
The maximum value for acceleration with active jerk limitation (SOFT/SOFTA) is
parameterized using the axis-specific machine data:
MD32434 $MA_SOFT_ACCEL_FACTOR
(scaling of the acceleration limitation with SOFT)
2.8.3 Programming
The function is not programmable.
24
Basic logic functions: Acceleration (B2)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0