Siemens SIMATIC PCS 7 CPU 410-5H System Manual page 331

Switched distributed I/O, PROFINET, CCF = 2 %
The estimate applies if the process allows for any device to fail.
Redundant CPUs with redundant I/O
The comparison only took account of the I/O modules.
Single-channel one-sided I/O
CPU 410-5H Process Automation
System Manual, 09/2014, A5E31622160-AB
Characteristic values of redundant automation systems
A.2 Comparison of MTBF for selected configurations
Factor
approx. 10
MTBF factor
1
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