Network Components - Siemens SIMATIC PCS 7 Function Manual

Bus systems set up as a ring are fault-tolerant. In ring structures, the signal path remains intact
even if there is a disconnection on the transmission cable at any point in the ring (for example
due to a wire break). The availability is ensured by ring redundancy.
This fault-tolerance is used in the following bus systems:
● Fault-tolerant terminal bus (Page 47)
● Fault-tolerant plant bus (Page 57)
● Fault-tolerant PROFIBUS PA (Page 68)
● Fault-tolerant PROFINET bus (Page 64)
The following sections describe the basics of these communications solutions.
3.3.1

Network components

Introduction
Local networks (LAN) form the basis of the communication system. The following are options
that can be implemented based on the specific system requirements:
● Electrical
● Optical
● Optical/electrical (mixed operation)
Overview of the network components
You can set up bus systems with the following link and switch modules of SIMATIC NET.
Note
OSM and OLM mixed operation is not permitted.
Fault-tolerant Process Control Systems (V8.0)
Function Manual, 03/2012, A5E02779471-02
Fault-tolerant Solutions in PCS 7
3.3 Solutions for communication
41