Siemens SINUMERIK Series Function Manual page 43

In addition, you can parameterize SDI so that SDI limits the speed to values in the permitted
direction.
Independently of one another, you can parameterize as to whether SDI limits the values in the
positive and/or negative direction.
Safety Integrated
Function Manual, 10/2015, 6FC5397-3EP40-5BA3
Overview of Safety Integrated functions
2.3 Safety Integrated Extended Functions
43