Rockwell Automation Publication ICSTT-RM447M-EN-P - July 2019 77
AADvance System Architectures Chapter 4
Figure 14 - Dual Processor System
Dual Architecture for Fault Tolerant Applications
Fault Tolerant Input and SIL 3 Outputs
A dual architecture configuration shown uses two dual redundant modules for
each stage. The use of two processor modules supplies SIL 3 integrity for the
processor stage (as for the previous example) while the second input module
supplies fault tolerance for the inputs.
A SIL 3 fault tolerant processor and I/O is achieved by dual input and output
module configurations with dual or triple processor modules.