Modern production facilities rely on various software applications to control and monitor their plants. These include applications for human-machine interfaces (HMI), process historians, expert systems, alarming, reports, trending, and countless others. These applications may be coupled together with the client/server technology of OPC. Thus, when properly designed and implemented, these systems can improve the efficiency and reliability of the plant, and consequently, its profitability. But what happens when a hardware device fails?
The OPC Redundancy Broker (ORB) seeks to eliminate data loss and maintain system reliability. It allows the user to implement a standby OPC server, which will take the place of the primary server in the event of failure. The criteria for defining server failure are customizable by the user within ORB.
ORB provides redundancy in a manner that is transparent to the OPC installation. When a failure occurs, the client is completely unaware that there is a new server; it simply continues operating as though nothing had occurred.
ORB is now equipped with the ability to connect to multiple pairs of the same OPC server. By allowing the user to create and assign program IDs to specific pairs, ORB can differentiate between servers running the same server application.