ISA88.5 & the State Model

(Sidebar to "ISA88 Beyond Batch" from the February 2008 issue of Automation World)

The packaging world is involved in the development of part 5 of ISA88, often dubbed Make2Pack. The coming standard leverages ISA88 batch standard principles and applies the PackML state model. PackML defines a state model developed by the Packaging Working Group of the Open Modular Architecture Control (OMAC) Users Group. The  goal was to develop guidelines for line types, machine state models and naming conventions for communication between production machinery within the packaging industry.

The PackML state model provides definitions for servo-driven packaging equipment, such as ready, running, holding and aborted. It is patterned after the state model used in ISA88 for batch processing, and provides the basis for a common language for supervisory control systems.

The Instrumentation, Systems and Automation Society (ISA), WBF (previously World Batch Forum) and OMAC formed a joint working group to harmonize batch standard principles and develop conceptual models, terminology and industrial automation examples. The guidelines developed by the Part 5 committee will be designed to apply to the total manufacturing process. “ISA88.5 is building a unified standard in the packaging world, including common models, terminology and definitions,” says Marcus Tennant, product manager for process software at vendor Rockwell Automation Inc., in Milwaukee. “If there is a batch process, there is probably a packaging process right behind it, so there are synergies between batch and packaging processes.”

ISA88.5 comes at the right time for the packaging industry, because packaging equipment is becoming more automated. “Packaging has gone through a revolution on the machinery side, so software integration was needed,” says Dennis Brandl, head of BR&L Consulting Inc., in Cary N.C., and chairman of the ISA88 committee. “ISA88 will make the software integrate, so we decided to start ISA88.5 and put it in the form of an international standard.”

ISA88.5 and the state model is part of a big push to bring structure into packaging. “A lot has happened in the past 18 months to enhance the state model—not just in the process side but also on the machine side in ISA88.5 developments,” says John Blanchard, principal analyst, ARC Advisory Group Inc., in Dedham, Mass. “There have been tremendous advances in the state model and there is growing acceptance of it in the machine industries.”

To see the main story this sidebar was taken from - "ISA88 Beyond Batch" - please visit http://www.automationworld.com/view-3896

More in Control