The benefits of connectivity among process plant automation and information systems and higher level computing platforms such as ERP systems and data historians have been touted for years. Advantages include widespread visibility of issues before they impact production, maximized throughput and supply chain optimization.
Implementing this level of connectivity can be very complex, but standards such as OPC, ISA-95 and Business to Manufacturing Mark-up Language (B2MML) can ease challenges. Using these and other standards can provide a vendor-independent format for data exchange, enabling seamless connections among systems from different suppliers.
In one recent project at a major oil refinery, Yokogawa's Manufacturing Data Exchange (MDX) software replaced a proprietary interface to integrate a plant's process control system with an aging, in-house ERP system that also incorporated a laboratory and composition management system. The scope of the project included a CS 3000 batch control system, an Exaquantum batch management system and MDX, along with associated engineering services, training and support—all supplied by Yokogawa.
"MDX is Yokogawa's standard-based software integration application for enterprise connectivity, enabling integration for both continuous and batch processes," says Wayne Matthews, technical director at Yokogawa Marex. "MDX supports web services and the ISA-95 enterprise-control system integration standard using B2MML."
For this project, MDX provides an interface that maps production schedules between the customer's ERP system and the batch control system. Batches are initiated with the sending of batch system schedules and material-based recipe parameters from MDX.
Upon receipt of the production schedule from the ERP system, the batch control system automatically creates batches, with a single production request typically sent from the ERP system for each order. The batch control system then interacts with other automation components as required to produce the batch.
After production, the batch control system sends a corresponding production performance message to the ERP system, reporting on actual production results. This batch production information allows the ERP system to be kept up to date with inventory information, which is used for scheduling future batches.
In addition to batch results, multiple production performance messages can be sent from the batch control system to the ERP system for each order. These messages can be triggered by a variety of conditions within the batch control system throughout the production cycle.
For this project, Yokogawa also assisted the customer in the development of a B2MML interface adapter to the custom ERP system. This custom ERP system is due to be replaced with a SAP R3 system including the NetWeaver ISA95 module, with which MDX has been certified. "Utilizing standards such as ISA95 and B2MML will make the future transition from the custom ERP system to SAP a relatively straightforward task," notes Matthews.
"The project provided our customer with a number of specific benefits, including increased functionality and accuracy in stock accounting. MDX's standards-based interface proved itself more robust than its custom-built predecessor, and the B2MML interface provided greater functionality, allowing for a richer message set and more detailed information than was previously available," explains Matthews.
"Previously, the custom system was prone to errors that required significant man hours for reconciliation, but our customer reports virtually no errors with the MDX system. As a result, the information produced is now trusted and is used for decision making in a way that just wasn't possible with the old system," concludes Matthews.