Communication Via S7 Connections - One-Sided Mode - Siemens SIMATIC PCS 7 System Manual

16.9.1

Communication via S7 connections - one-sided mode

Availability
Availability for communication between a fault-tolerant system and a standard system is also
increased by using a redundant plant bus instead of a single bus (see figure below).
Figure 16-8
With this configuration and redundant operation, the fault-tolerant system is connected to the
standard system via bus1. This applies no matter which CPU is the master CPU.
For linked fault-tolerant and standard systems, the availability of communication cannot be
improved by means of a dual electrical bus system. To be able to use the second bus
system as redundancy, a second S7 connection must be used and managed accordingly in
the user program (see next figure).
CPU 410-5H Process Automation/CPU 410 SMART
System Manual, 09/2014, A5E32631667-AB
Example of linking standard and fault-tolerant systems in a simple bus system
Supplementary information
16.9 Communication via S7 connections
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