Siemens Sinamics S110 Function Manual page 163

Figure 7-23 Control principle using DSC
Activating
If the prerequisites for DSC are met, the DSC structure is activated through a logical
combination of the parameters p1190 "DSC position deviation XERR" and p1191 "DSC
position controller gain KPC" through a selected suitable PROFIdrive telegram.
If KPC = 0 is issued, only speed control with the speed pre-control value (p1430, typically
N_SOLL_B) can be used. Position controlled operation requires a transfer of KPC > 0.
When DSC is activated, it is recommended to use a new setting for the position controller
gain KPC in the master.
When DSC is activated, the channels p1155 and p1160 for the position setpoint values as
well as the channel for the extended setpoint value are not used.
The p1430 value for speed pre-control is still taken into account.
Deactivating
If both KPC = 0 (p1191=0) and XERR = 0 (p1190 = 0) are set, the DSC structure is dissolved
and the "DSC" function is deactivated. In this case, only the value from p1430 from speed
pre-control is taken into account.
Since it is possible to set higher gain factors using DSC, the control loop can become
unstable when DSC is disabled. For this reason, before deactivating DSC, the value for KPC
in the master must be reduced.
Drive functions
Function Manual, 10/2008, 6SL3097-4AB10-0BP0
Drive functions
7.1 Servo control
163