Siemens SINAMICS G120D List Manual page 337

Note: The maximum acceleration appears to exhibit jumps (without jerk).
"Traversing blocks" operating mode:
The programmed acceleration override (p2619) acts on the maximum acceleration.
"Direct setpoint input/MDI" mode:
The acceleration override is effective (p2644, 4000 hex = 100 %).
"Jog" and "search for reference" modes
No acceleration override is active. The axis starts with the maximum acceleration.
p2573 EPOS maximum deceleration / -a_max
CU250D-2_DP_F Access level: 1
CU250D-2_PN_F
Can be changed: T
Units group: -
Min
1 [1000 LU/s²]
Description: Sets the maximum deceleration for the "basic positioner" function (EPOS).
Dependency: Refer to: p2620, p2645
Note: The maximum deceleration appears to exhibit jumps (without jerk).
"Traversing blocks" operating mode:
The programmed deceleration override (p2620) acts on the maximum deceleration.
"Direct setpoint input/MDI" mode:
The deceleration override is effective (p2645, 4000 hex = 100 %).
"Jog" and "search for reference" modes
No deceleration override is effective. The axis breaks with the maximum deceleration.
p2574 EPOS jerk limiting / Jerk lim
CU250D-2_DP_F Access level: 1
CU250D-2_PN_F
Can be changed: U, T
Units group: -
Min
1 [1000 LU/s³]
Description: Sets the jerk limiting
Dependency: Refer to: p2572, p2573, p2575
Note: The jerk limiting is internally converted into a jerk time as follows:
Jerk time Tr = max(p2572, p2573) / p2574
The jerk time is internally limited to 1000 ms and is rounded-off to an integer multiple of the sampling time position-
ing (p0115[5]).
The jerk time is valid for the acceleration and deceleration phases also for unequal maximum acceleration (p2572)
and maximum deceleration (p2573).
For unequal maximum acceleration and maximum deceleration, the motion is not optimal from a time perspective
as the jerk limit cannot be used for the lower of the two values.
If, in the traversing profile, the acceleration time without jerk limiting is less than the jerk time Tr, then the motion
with jerk limiting is not optimum from a time perspective.
For traversing motion with a direct transition between acceleration and deceleration (i.e. jerk time is greater than the
constant velocity phase), jerk can increase up to twice the parameterized jerk.
CONTINUE_FLYING with direction reversal acts internally just like a CONTINUE_WITH_STOP without the "posi-
tion reached" being set. Without jerk limiting, this behavior can hardly be noticed as, when reversing, the position
setpoint is only kept at zero for one interpolator clock cycle.
For block change enable CONTINUE_WITH_STOP, jerk limiting results in a longer delay time.
© Siemens AG 2012 - 2013 All Rights Reserved
SINAMICS G120D List Manual (LH14), 01/2013
Calculated: -
Scaling: -
Unit selection: -
Max
2000000 [1000 LU/s²]
Calculated: -
Scaling: -
Unit selection: -
Max
100000000 [1000 LU/s³]
Parameters
List of parameters
Data type: Unsigned32
Dyn. index: -
Func. diagram: 3630
Factory setting
100 [1000 LU/s²]
Data type: Unsigned32
Dyn. index: -
Func. diagram: 3635
Factory setting
10000 [1000 LU/s³]
1-337