System Configurations With Distributed I/Os - Siemens SIMATIC PCS 7 CPU 410-5H System Manual

Characteristic values of redundant automation systems
A.2 Comparison of MTBF for selected configurations
A.2.2

System configurations with distributed I/Os

The system with two fault-tolerant CPUs 410-5H and one-sided I/Os described below is
taken as a basis for calculating a reference factor which specifies the multiple of the
availability of the other systems with distributed I/Os compared with the base line.
Redundant CPUs with single-channel one-sided or switched I/O
One-sided distributed I/O
Switched distributed I/O, PROFIBUS DP, CCF = 2 %
330
Base line
1
Factor
approx. 15
CPU 410-5H Process Automation
System Manual, 09/2014, A5E31622160-AB