Configuring The F-Cpu - Siemens SIMATIC S7 Configuration And Programming Manual

1.1.5

Configuring the F-CPU

Information on Local Data
The information below on defining local data for the safety program completely
replaces the corresponding information in Section 3.3 of the manual.
"F-Local Data" Parameter
F-blocks are automatically added when the safety program is compiled to create an
executable safety program from your safety program. Use this parameter to define
the amount of local data in bytes that is available for the automatically added
F-blocks and the F-CALL.
Note
You must provide at least 300 bytes of local data for the safety program.
However, the local data requirement for the automatically added F-blocks may be
higher depending on the requirements of your safety program.
Thus, you should provide as much local data as possible for the automatically
added F-blocks.If the amount of local data available for the automatically added
F-blocks is insufficient (less than 300 bytes), the runtime of the safety program
increases. You will receive a notice via S7 Distributed Safety, if the automatically
added F-blocks would require more local data than configured. The safety-related
program will be generated anyway.
Safety Note
!
The calculated maximum runtime of the safety program using the MS Excel file in
the directory (...\Siemens\STEP7\S7Manual\s7fco\s7fcotib.xls) is no longer be
correct in this case, because the calculation assumes sufficient F-local data are
available.
In this case, use the value you configured for the max. cycle time of the F run-time
group (F-monitoring time)to calculate the max. reaction times in the event of an
error and for any run-time of the standard system using the above-mentioned
Excel file.
Product Information for the S7 Distributed Safety, Configuring and Programming Manual
A5E00169432-02
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