ISA95 “Levels” for Enterprise Integration

Oct. 7, 2008
Purdue Reference Model, “95” Provides a Model that End Users, Integrators and Vendors Can Share in Integrating Applications at Key Layers in the Enterprise

Level 0—The physical process — Defines the actual physical processes.

Level 1—Intelligent devices — Sensing and manipulating the physical processes. Process sensors, analyzers, actuators and related instrumentation.

Level 2—Control systems — Supervising, monitoring and controlling the physical processes. Real-time controls and software; DCS, human-machine interface (HMI); supervisory and data acquisition (SCADA) software.

Level 3—Manufacturing operations systems — Managing production work flow to produce the desired products.Batch management; manufacturing execution/operations management systems (MES/MOMS); laboratory, maintenance and plant performance management systems; data historians and related middleware. Time frame: shifts, hours, minutes, seconds.

Level 4—Business Logistics Systems — Managing the business-related activities of the manufacturing operation. ERP is the primary system; establishes the basic plant production schedule, material use, shipping and inventory levels. Time frame: months, weeks, days, shifts.

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