From a surge in the 1980s with the advent of the personal computer, data acquisition and control has taken over the development and manufacturing environments. As this nascent discipline emerged, engineers have been looking for better ways to wrangle the tremendous amount of data collected for design verification and process improvement.
With such a rapidly evolving environment, almost every design and manufacturing company developed their own way to handle data and manage their particular domain knowledge from their collected data. In 1995 the International Society of Automation published the ISA-95 standard as a framework to describe these activities in a typical manufacturing environment.
This slide set provides an overview of the various layers of the ISA-95 framework for a typical manufacturing environment and how data flows in a manufacturing execution system. The intent of this presentation is now “how to” design a particular MES system but rather to establish a common framework for all such systems.
2. 1. Manufacturing Execution System (MES)
definition
2. MES Activities
3. MES System Levels as defined in ISA-95
4. MES System Level Interactions
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3. Manufacturing Execution Systems (MES), are information
technology systems that manage manufacturing
operations in factories.
The scope of such systems in terms of activities may
include:
Management of product definitions
Management of resources
Scheduling (production processes)
Dispatching production orders
Execution of production orders
Collection of production data
Production performance analysis
Production Track & Trace
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4. ◦ Management of product definitions
Storage, version control and exchange with other systems of
master data such as product production rules, bill of material,
bill of resources, process set points and recipe data which are
all focused on defining how to make a product.
◦ Management of resources
Registration, exchange and analysis of resource information,
aiming to prepare and execute production orders with resources
of the right capabilities and availability.
◦ Scheduling (production processes)
These activities determine the production schedule as a collection
of work orders to meet the production requirements These
orders are typically received from enterprise resource
planning or specialized advanced planning and
scheduling systems.
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5. ◦ Dispatching production orders
Depending on the type of production processes this may
include further distribution of batches, runs and work
orders, issuing these to work centers and adjustment to
unanticipated conditions.
◦ Execution of production orders
Although actual execution is done by Process
control systems, an MES may perform checks on resources
and inform other systems about the progress of production
processes.
◦ Collection of production data
Collection, storage and exchange of process data, equipment
status, material lot information and production.
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6. ◦ Production performance analysis
Create useful information from raw collected data about
the current status of production such as Work In
Progress (WIP) overview as well as the production
performance of the past period for Overall Equipment
Effectiveness (OEP) or similar Performance Indicators.
◦ Production Track & Trace
Registration and retrieval of related information in order
to present a complete history of lots, orders or
equipment.
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8. Examples of systems acting on ISA-95 level 4 are:
◦ Product Lifecycle Management (PLM)
◦ Enterprise Resource Planning (ERP)
◦ Customer Relationship Management (CRM)
◦ Human Resource Management (HRM)
To PLM: production test results
From PLM: product definitions, bill of operations (routings),
electronic work instructions, equipment settings
To ERP: production performance results, produced and
consumed material
From ERP: production planning, order requirements
To CRM: product tracking and tracing information
From CRM: product complaints
To HRM: personnel performance
From HRM: personnel skills, personnel availability
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9. Examples of systems acting on ISA-95 level 3 are:
◦ Production Information Management System (PIMS)
◦ Warehouse Management System (WMS)
◦ Computerized Maintenance Management
System (CMMS)
To PIMS: quality test requests, sample lots, statistical process
data
From PIMS: quality test results, product certificates, testing
progress
To WMS: material resource requests, material definitions,
product deliveries
From WMS: material availability, staged material lots, product
shipments
To CMMS: equipment running data, equipment assignments,
maintenance requests
From CMMS: maintenance progress, equipment capabilities,
maintenance schedule
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10. Systems acting on ISA-95 level 2 are:
◦ Supervisory Control And Data Acquisition (SCADA)
◦ Programmable Logic Controllers (PLC)
◦ Distributed Control Systems (DCS)
◦ Batch Automation Systems
Information flows between MES and these process control
systems are roughly similar:
To DCS: work instructions, recipes, set points
From DCS: process values, alarms, adjusted set points,
production results
Plant floor data is first collected and diagnosed for real-time
control in a DCS or SCADA system then connected to these
Level 2 systems for exchanging plant floor data.
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