Redundant I/O In The One-Way Dp Slave - Siemens SIMATIC S7-400H Manual

2. Redundant I/O in the one-way DP slave

The signal modules are installed in pairs in the distributed I/O device ET 200M
with active backplane bus.
Figure 7-4
Automation System S7-400H Fault-tolerant Systems
A5E00068197-07
Redundant module pair
Redundant I/O in the one-way DP slave
Using I/O on the S7-400H
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