Technical data

Appendix
CPU 317T: Technology Functions
A5E00251798-03
A-25
A.3.2.4 Setting actual value coupling at the synchronization object
In the configuration of the synchronization object, it is determined whether to use
the setpoint or actual values of the leading axis object.
• physical axes - reference value/actual value coupling
• virtual axes - reference value coupling only
• external encoder - actual value coupling only
Extrapolation
The reference value for actual value coupling can be extrapolated for the
compensation of dead time.
The extrapolation is set and configured for the leading axis in the S7T Config
Experts list by means of extrapolation.extrapolationTime.
Filtering
Extrapolation of the position is based on the filtered or averaged velocity value.
• timeConstant: Timebase used to calculate the mean value, or time constant for
filtering
• extrapolationTime: Specified time for extrapolation
Extrapolation is not performed if 0.0 is specified.
The extrapolated position and velocity value are indicated in the system variable
extrapolationData.
The extrapolation compensates for the local delays that result from use of the
actual value instead of the setpoint.