Solutions For The Fieldbus; Redundant Profibus Dp - Siemens Simatic PCS 7 Function Manual

High availability solutions in PCS 7
4.3 Solutions for communication
4.3.5

Solutions for the fieldbus

4.3.5.1

Redundant PROFIBUS DP

Functionality
The field bus is used for data exchange between the automation system (AS) and the
distributed I/O. PROFIBUS DP (distributed peripheral)-- the field bus standard for
manufacturing and process automation--is used. PROFIBUS DP includes the specifications
for the following elements:
● Physical bus characteristics
● Access method
● User protocol
● User interface
PROFIBUS DP is suitable for fast, cyclic data exchange with field devices. It is used to connect
distributed I/O, for example, ET 200M, with very fast response times.
It is often advantageous to connect several DP master systems to an automation system in
order to increase the number of I/O components that can be connected. This also enables
segments to be formed, allowing individual production areas to operate independent of one
another.
High availability communication solutions
The following high availability communication solutions are offered for PROFIBUS DP:
● Redundant PROFIBUS DP as an electrical network
● Redundant PROFIBUS DP with OLMs (optical network)
Configuration
The S7-400H high availability automation system features a DP master interface on each CPU
for connecting to PROFIBUS DP. The redundant PROFIBUS DP connects the redundant
DP master to the redundant interface modules of the distributed I/O.
The following figure shows an example for connecting redundant distributed I/O based on
ET 200M to a redundant PROFIBUS DP.
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High Availability Process Control Systems (V9.0)
Function Manual, 05/2017, A5E39221836-AA