ISA88, batch control standard, Part 1 revision nears completion
ISA88 Batch Control Part 1 revisions are out for vote, and the three-year revision effort may be finalized by early 2010. ISA88.01 Batch Control Part 1: Models and Terminology was originally passed in 1995.
Part 1 revisions fix some errors in the original and solidify unintended leeway in original language. Among clarifications:
– Control modules execute basic control;
– Equipment modules contain procedural control;
– Procedural control execution inside units is part of the unit supervision activity;
– Relationships among types of recipes, recipe components, and equipment control are more fully described and illustrated;
– Entity relationship diagrams have been replaces with easier to understand instance diagrams;
– State diagram replaces a transition diagram for the procedural states example; and
– References to ANSI/ISA95 Enterprise-Control System Integration and IEC 62264-1 provide more clarifications.
|David A. Chappell|
The update effort took longer than hoped, incorporating input from industries outside of the batch world, says David A. Chappell, ISA88 Part 1 voting member and Part 5 chair. "The technical report, TR88.00.02-2008 Machine and Unit States: An Implementation Example of ISA-88, lead by the packaging industry provided great insight into some improvements that will allow the ISA88 series of standards to have a much greater impact on all of manufacturing industries and not just those focused upon batch," he says.
Those who apply the ISA88 standards will create products that rely on less "interpretation," Chappell suggests, better meeting the standard’s intent by adhering to compliance and conformance requirements.
Next, ISA88 Part 5 is being drafted to provide additional clarity and guidance for models and terminology of modular equipment control (especially useful where batch manufacturing meets packaging manufacturing). Additional work, updates to Part 2 and a possible Part 6, may provide more help with how equipment depends on and relates to other equipment (procedural hierarchies).
Learn more about ISA88 Part 5 .
Read a Control Engineering feature article on a batch control project .
– Mark T. Hoske, editor in chief, Control Engineering www.controleng.com