Siemens SIMATIC S7 F, Manual

Page: 183 / 354

Safety
Fail-Safe Systems
A5E00085588-03
7-17
Configuration
•
F-I/Os that are supposed to have the same safety-relevant module parameters
can be copied during configuration. Their safety-relevant module parameters
no longer have to be checked individually: It is enough to compare the
’Parameter CRC (without address)’ of the copied F-I/Os with the ’Parameter
CRC (without address)’ of the already checked F-I/Os and to check the logical
start addresses.
•
After advance acceptance of the configuration of an F-I/O, it is sufficient to
compare the ’Parameter CRC (incl. address)’ in the new printout and the one in
the accepted printout of the configuration.
Programming
The following parameters of fail-safe blocks must be checked in the printout:
•
Any safety-related input parameters that are not automatically assigned must
be checked in the printout – either in the CFC charts or in the section on
safety-related parameters. Input parameters that are not visible in the CFC
charts are printed out in the section on safety-related parameters. If it is easier
to check the parameters in the chart than in the section on safety-related
parameters, the parameters should not be hidden.
•
At each F module driver, the assignment to the F channel drivers at the
CHADDRxx I/Os must be checked using function tests or by looking at the
printout.
•
The initial values of safety-related output parameters must be checked if the
run sequence does not correspond to the flow of data, i.e. if the block is only
called after the output parameter has been transferred to another block. This
happens, for example, in the case of feedback. These output parameters are
printed out in the safety-related parameters section and marked with an (*).