Siemens SINUMERIK 840D sl Function Manual page 46

Detailed description
3.3 System variables for synchronized actions
The axial jerk is limited to the value set in MD32430 $MA_JOG_AND_POS_MAX_JERK (axial
jerk).
Note
No predictive velocity control can be made for the overlaid $AA_OFF motion. This can cause
a discontinuous velocity change, in particular for clocked specification (via synchronous
actions) for $AA_OFF overlay values. In such cases, we recommend the deactivation of the
jerk limitation when possible.
Upper limit of the compensation value
The value of $AA_OFF can be limited via the following setting data:
SD43350 $SA_AA_OFF_LIMIT (upper limit of the compensation value $AA_OFF in case of
clearance control)
The status of the limitation can be read via the following system variable:
$AA_OFF_LIMIT[<axis>] == <value>
Value
-1
1
0
Reset behavior
With static synchronized actions (IDS = <number> DO $AA_OFF = <value>), deselection
of the position offset effective in $AA_OFF results in an immediate new overlaid movement.
The reset behavior with regard to $AA_OFF can therefore be set via the following machine
data:
MD36750 $MA_AA_OFF_MODE, bit 1 = <value>
<value>
0
1
JOG mode
Execution of an overlaid movement because of $AA_OFF can also be enabled for JOG mode:
MD36750 $MA_AA_OFF_MODE, bit 2 = <value>
<value>
0
1
A mode change to JOG mode is only possible when the current position offset has been
traversed. Otherwise the following alarm is displayed:
46
Meaning
Compensation value is limited in the negative direction
Compensation value is limited in the positive direction.
No limitation of the offset value
Meaning
The position offset in $AA_OFF is deselected with RESET
The position offset in $AA_OFF is retained after RESET
Meaning
JOG mode: Overlaid movement because of $AA_OFF disabled
JOG mode: Overlaid movement because of $AA_OFF enabled
Function Manual, 08/2018, 6FC5397-5BP40-6BA2
Synchronized actions