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NOV-DEC 2017

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28 INTECH NOVEMBER/DECEMBER 2017 WWW.ISA.ORG FACTORY AUTOMATION concept is not de- fined by ISA-95. The overview of the Operations Event Mod- el (figure 3) illustrates the operation event definition and the re- lationship with the op- erations event message occurrence. As shown in figure 4, The Unified Modeling Language (UML) dia- gram of the Operations Event Model shows the operations event object primarily defining an event occurrence by the operations event re- cord in an occurrence message. The self- describing operations event messages contain all the information explicitly or via reference links for the required in- formation describing the operations or process control event. The operations event definition record specification and operations event class record specifica- tion define the message definition of the event structure of the set of changed data objects. They are used to configure different operations event occurrences to a known explicit event structure or definition. Real-time industrial EDA The operation event message is a post/ publish-notify/subscribe (typically) in- dependent asynchronous process. An industrial event-driven architecture (EDA) typically consists of: l operations event producers l operations event consumers l publication systems l operations event channels An operations event producer (pub- lisher) does not have to know about the subscribing operations event consumers (receivers) and their data subset requirement that is logically processed out of the operations event message. The consumers apply the operations event definition from the producer to know explicitly how to logically parse the operations event message. The receiver only abstracts the event information required to con- trol its operations or physical process- es. Depending on the manufacturing operations or process control require- ments (what is being made and how), the industrial real-time EDA takes on various forms: l An operations event producer may manage the assembly and control triggers of operations events. l An operations event channel may manage the control triggers and dis- tribution of operations events. l The operations event message can be generated from applications or from inside the plant's data exchange infra- structure/mediation components. l The EDA implementation is typically applied in combination with other messaging exchange patterns, such as request-response, depending on the requirements. l The EDA can be applied over a va- riety of technology landscapes with or without an enterprise service bus (ESB), manufacturing service bus (MSB), or similar environments to non-ESB environments. ° The data exchange infrastructure may be performed using many non-ESB/MSB approaches, such as .NET, a rich-site-summary (RSS) feed, an atom feed (Atom Syndica- tion Format, an XML language used for Web feeds), an APP (Atom Pub- lishing Protocol, a simple HTTP- based protocol for creating and up- dating Web resources), or a simple file-share method (peer-to-peer [P2P] file sharing for exchanging large files on an intranet). ° With IIoT, many transport protocols and methods can be introduced into industrial environments for data exchange. Common MOM events In 2017, the ISA95 committee produced working draft 01 for ANSI/ISA-95.00.09- ed1, Enterprise-Control System Integra- tion − Part 9: Common Manufacturing Operations Management Events. This working draft will be going through de- velopment through 2018; however, the common operations events are defined in the context of the ANSI/ISA-95.00.03- 2013 – Part 3: MOM Generic Activity Model for the common process-centric Event consumer Event consumer Event consumer Event producer Publication Notification Notification Notification Figure 5. Basic behavior of an industrial event-driven architecture Figure 6. The pro- posed common MOM events per Part 9 Working Draft 01 Definition management Dispatching Tracking Resource management Execution management Data collection Performance analysis Detailed scheduling Operations level 1 / level 2 functions Level 4 functions ISA-95 function Operations event Test specified Test adjusted Test retired Resource defined Resource acquired Resource adjusted Resource retired Work commenced Work redirected Work completed Work aborted Work executed Work reconciled Operations scheduled, operations rescheduled Performance tracked performance reconciled Work scheduled work rescheduled Work capability managed Operations capability managed Operations defined Legend Level 4 Level 3 Level 3 Level 2 Work defined Work defined Work dispatched

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