Siemens SIMATIC PCS 7 Function Manual page 61

Availability - redundant, fault-tolerant plant bus
The block diagram for a redundant, fault-tolerant plant bus with two CPs each in both OS
servers and additional switches appears as follows:
In this system, one CP 16x3 can fail in each OS server or one CP 443‑1 in each subsystem
of the AS without this affecting the complete system. There are two plant buses (busses), each
set up with redundant switches. This guards against the failure of the bus and all components
involved (switches).
Additional information
● Section "Connecting PC stations to the plant bus (Page 56)"
● Section "Media Redundancy Protocol (Page 45)"
● Section "How to configure a fault-tolerant plant bus (Page 100)"
● Documentation
● Manual
● Operating Instructions
● Manual
● Manual
Fault-tolerant Process Control Systems (V8.0)
Function Manual, 03/2012, A5E02779471-02
PCS 7 Released Modules
SIMATIC Net Twisted Pair and Fiber-Optic Networks
SIMATIC NET; Industrial Ethernet Switches SCALANCE X-400
SIMATIC NET Industrial Ethernet OSM/ESM Network Management
SIMATIC Communication with SIMATIC
Fault-tolerant Solutions in PCS 7
3.3 Solutions for communication
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