Siemens SIMATIC PCS 7 Function Manual page 117

Procedure
1. Configure redundant modules for HART field devices in HW Config as described in section
Figure 4-1
2. Place the "HART field device" in the detail view of the redundant module.
Fault-tolerant Process Control Systems (V8.0)
Function Manual, 03/2012, A5E02779471-02
"How to configure redundant I/O modules (Page 112)."
in the example, the module has been configured for slot 6:
– ET 200M station with PROFIBUS address 4: Module 6
– ET 200M station with PROFIBUS address 6: Module 6
Redundant module selected.
In the example, module 6 on ET 200M station with PROFIBUS address 4.
Advantages of fault-tolerant components
4.4 Distributed I/O
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