Siemens SINUMERIK 840D sl Function Manual page 267

2.18.2.2 Commissioning
Function
The knee-shaped acceleration characteristic curve is activated for a specific machine axis
using the machine data:
MD35240 $MA_ACCEL_TYPE_DRIVE = TRUE
Single-axis interpolation
As soon as the knee-shaped acceleration characteristic curve is activated, in the case of
single-axis interpolations (positioning axis, reciprocating axis, manual travel, etc.), traversing
is performed exclusively in DRIVEA mode.
Switching of the acceleration profile via the part-program instructions:
• Abrupt acceleration changes (BRISKA)
• Acceleration with jerk limitation (SOFTA)
is not possible.
Path interpolation
If the knee-shaped acceleration characteristic curve is parameterized for a machine axis that
is of relevance for a programmed path, but the DRIVE part-program instruction has not
been activated, then a substitute characteristic curve with lower dynamic limit values is
generated for the path.
2.18.3 Programming
2.18.3.1 Channel-specific activation (DRIVE)
Syntax
DRIVE
Functionality
The knee-shaped characteristic curve is activated for path acceleration using the DRIVE
part-program instruction.
G group: 21
Effective: Modal
Reset response
The channel-specific default setting is activated via a reset:
MD20150 $MC_GCODE_RESET_VALUES[20]
Basic logic functions: Acceleration (B2)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
2.18 Kneeshaped acceleration characteristic curve
Functions
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