Siemens Sinamics S110 Function Manual page 301

Calculation time load for firmware version 4.1
Processing of free function blocks requires calculation time. If calculation time is becoming
short, you will need to check whether all the activated function modules are required and
whether all the function blocks used need to be calculated within the same sampling time.
The calculation time load can be reduced by either deactivating function modules or
assigning used function blocks to a runtime group with a longer sampling time.
Dependency
The resulting calculation time load depends on the following:
● Number of activated runtime groups (p20000[x] > 0)
● Number of calculated function blocks
● Sampling time
Calculation time online
The calculation time load shown in r9976[0...7] does not include the additional load caused
by the free function blocks.
Note
For the basic SINAMICS system as of firmware version 4.1, the following applies:
As of this version, the process of determining the calculation time load is different. For this
reason, r9976[0...7] no longer contains the calculation time load generated by the "free
function blocks".
Calculation time offline
When the system is in offline mode, SIZER offers an approximate statement regarding
whether a configuration can be computed on SINAMICS S110. The additional calculation
time load is not taken into account when the "free function blocks" function module is
activated.
Function Manual
Function Manual, 01/2011, 6SL3097-4AB10-0BP3
Drive functions
7.3 Function modules
299