PlantStruxure PES [V4.1]: How to configure Peer2Peer communications (controller to controller) in PES
Goals and Symptoms
The purpose of this document is to summarize the Peer2Peer communications features available in PES 4.1 and to provide typical examples that can be found in real projects.
Facts and Changes
This document has been created for PES version 4.1.
Causes and Fixes
Peer2Peer communications means data exchange between controllers, which is a common requirement in DCS systems. Peer2Peer communication is implemented in PES system using Modbus TCP implicit messaging (IO Scanner) as the communication channel.
It is possible to define a Peer2Peer communication channel between a controller communication card with Modbus TCP/IP having IO scanner capability and a controller that acts as a Modbus TCP/IP server. On top of this communication channel, using PES it’s possible to add a certain amount of “network variables”.
A network variable is a Unity variable (elementary or derived) defined in a certain control project (having the role of the “owner”) whose value has to be transferred to another control project (having the role of the “consumer”).
This document describe difference aspect of Peer2Peer communication in both owner controller and consumer controller.