Monitoring Communication Between F-Shutdown Groups - Siemens SIMATIC PCS 7 Operating Manual

7.11.5

Monitoring communication between F-shutdown groups

Time monitoring is implemented in the F_R_BO or F_R_R F FBs and configured at the
"TIMEOUT" input parameter of the receive block.
To prevent time monitoring from being triggered when no errors are present, the TIMEOUT
monitoring time must be set to a value which is at least equal to the higher of the two
maximum cyclic interrupt cycle times of F_S_R or F_S_BO and F_R_R or F_R_BO. The
lowest value for the timeout time can be determined using S7ftimea.xls.
You will need the following parameters to calculate the "TIMEOUT" parameter:
T
CImax1
T
CImax2
The values for T
the F_CYC_CO-OBxx F function block (xx = Number of the cyclic interrupt OB with the
send/receive block).
Compendium Part B - Process Safety (V8.2)
Operating Manual, 07/2016, A5E35031794-AB
Maximum cycle time of the cyclic interrupt OB in which the associated send block
F_S_BO or F_S_R is called.
Maximum cycle time of the cyclic interrupt OB in which the receive block F_R_BO
or F_R_R is called.
/T can be found in chart @F_CycCo-OBxx, at input MAX_CYC of
CImax1 Clmax2
Configuring the safety program
7.11 Monitoring times and system response times
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