Configurations and Help with Selection
2.3 Configuration Variants for Fail-safe Systems According to Availability Requirements
Safety Engineering in SIMATIC S7
System Manual, 04/2006, A5E00109529-05
2-19
Configuration Example of S7 FH Systems: Single-channel Switched I/O
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Figure 2-13 S7 FH Systems with Single-channel Switched I/O
Limits of Availability with Single-channel Switched I/O
Switched I/O are no longer available to the process in case of:
•
Failure of the fail-safe signal module
(relevant fail-safe signal module is passivated)
•
Failure of the entire ET 200M
Switched I/O are still available to the process in case of:
•
Failure of an IM153-2/-3/-2 FO
•
Failure of a PROFIBUS DP line
•
Failure of an F-CPU