Method and device for exchanging data based on the OPC communication protocol between the redundant components of a process control system

摘要

The method involves connecting an Open connectivity client (28) with the master OPC server (22) by a communication connection (26), and with that a ready OPC server (24) is connected by another communication connection. The open connectivity (OPC) client exchanges data with automation devices. The data coming from the master OPC server and the ready OPC server, is evaluated. The data is switched to the ready OPC server partly by the master OPC server in case of an error by the OPC client, in such a way that the program execution is smoothly continued at the same place. An independent claim is also included for the device for the exchange of data on basis of the OPC communication protocol.