Siemens SINUMERIK MC Commissioning Manual page 77

3. If necessary, you can manually change the F-OB number that the system suggests. When
doing this, observe the number ranges permissible for the particular event class.
4. For F-OBs with event class "Cyclic interrupt", parameterize cycle time, phase shift and
priority.
– Select a cycle time that is less than the "Maximum cycle time of the F-runtime group" and
– Select a phase offset that is less than the cycle time.
– If possible, select a priority that is higher than the priority of all other OBs.
②
Main safety block
Assign the main safety block to be called to the F-OB. If the main safety block is an FB, then you
must also assign an instance DB. As default value, Main_Safety_RTG1 and
Main_Safety_RTG1_DB are suggested.
Safety Integrated (with SINAMICS S120)
Commissioning Manual, 02/2020, A5E46305916B AB
less than the "Warning limit cycle time of the F-runtime group".
Note
The higher F-OB priority means that you can ensure that the runtime of the safety
program and the response time of your safety functions is influenced as little as possible
by the standard user program.
Safety program of the F-PLC
3.8 F-runtime groups
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