Siemens SINAMICS S120 Function Manual page 514

Function modules
8.8 Basic positioner
Jerk limitation
Acceleration and deceleration can change suddenly if jerk limiting has not been activated.
The diagram below shows the traversing profile when jerk limitation has not been activated.
The maximum acceleration (a
drive accelerates until the target speed (v
velocity phase.
Figure 8-15
Jerk limitation can be used to achieve a ramp-like change of both variables, which ensures
"smooth" acceleration and braking as shown in the diagram below. Ideally, acceleration and
deceleration should be linear.
Figure 8-16
The maximum gradient (r
for both acceleration and braking. The resolution is 1000 LU/s
permanently, set parameter p2575 (Activate jerk limitation) to 1. In this case, limitation
cannot be activated or deactivated in traversing block mode by means of the command
"JERK". Switching the limitation on/off in the traversing block mode requires parameter
p2575 (Activate jerk limitation) to be set to zero. The status signal r2684.6 (Jerk limitation
active) indicates whether or not jerk limitation is active.
514
) and deceleration (d
max
Without jerk limitation
Activated jerk limitation
) can be set in parameter p2574 (jerk limitation) in the unit LU/s
k
) are effective immediately. The
max
) is reached and then switches to the constant
target
. To activate the limitation
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Function Manual, 11/2017, 6SL3097-4AB00-0BP5
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Drive functions