Siemens SIMATIC S7 F, Manual

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Fail-Safe Blocks
Fail-Safe Systems
8-12
A5E00085588-03
Startup Characteristics
After a startup (cold restart or warm restart), communication must first be
established between the F module driver and the digital input module. In this time,
the substitute value 0 is output with the quality code (QUALITY) 16#48, and the
outputs QBAD = 1 and PASS_OUT = 1 are set as well.
Error Handling
In the event of an error that is critical to safety, the system function SFC F_CTRL
is called. This records the event in the Diagnostic Buffer and requests a switch to
the reserve CPU if the error occurred only on the master CPU. For non-redundant
systems or a common-cause error occurring in both CPUs, the shutdown logic can
be configured to either disable the erred F-run-time group or the entire Safety
Program.
Error Information in Diagnostic Buffer
Error Code (W#16#...) Description
75DAH Error in the safety data format (error due to online modification
of the Safety Program or internal CPU fault)
Report Characteristics
The block has no reporting behavior.
See Also
Common Features of the Driver Blocks
Passivation and Reintegration