MES is often referred to as MOM. Where MES stands for “Manufacturing Execution System” and MOM stands for “Manufacturing Operation Management”.
MES design is based on data acquisition, communication, planning and scheduling, task management, production collaboration and other plant operations.
MES is a level 3 system that links the level 4 as Business System (ERP) and level 0-2 as the real-time operational plant control (PLC’s).
ERP systems (Enterprise Resource Planning) track the business system which mainly covers financial functions, customer orders and sending production requests to the factory floor (chemical plant).
A level 3 MES is an electronic system that reduces a lot of paperwork in the industry by keeping all the data about overall control and management of the factory floor (production plant). MES keeps track of any updates occur in the real-time operation plant. It also provides all the updated information to ERP System.
MES manages the flow of production by providing information in the sequence at which work needs to be done, especially in terms of jobs, work orders and batches by dispatching production to specific equipment and personnel of the plant.
MES is a versatile design that helps to meet the actual needs of the manufacturing industry.
It provides measurements in real-time operation where proper attention is required to analyse the problems and to make sure the proper quality control of the product during manufacturing.
It also manages offline inspection of operations in the plant.
This is a system where we see all data regarding operational production, parametric data with respect to processes and equipment in the production.
It monitors production by either providing or automatically correcting and improving processes in the process operations. It also provides an alarm if there is a false condition occur during the production.
It helps to eliminate non-value-add activities.
It also helps to accelerate trace analysis (activities like product purity or other manufacturing issues) and root cause diagnosis.
Use of MES helps to improve the product quality and implement new design depending on the vendor or market requirement.
MES gives a fact-based operational and strategic decision. By implementing all these activities will give us complete control over manufacturing processes.
Figure 2 : MES Functionality
Automation Pyramid:
Automation Pyramid is the diagrammatic representation of different levels of automation in the industry. It is also called a visual representation of how automation technology is being integrated within the industry.
At the bottom of the pyramid, there is a field level which is also called a production floor. It represents the devices, actuators, and sensors seen in the production plant field or factory floor. This level does physical work and monitoring in the plant. Field level includes electric motors, hydraulic and pneumatic actuators to move machinery, proximity switches and photoelectric switches to detect the movement of certain materials. All these devices will play a vital role at the field level.
The next level after the field is Control Level. This level uses all the devices which actually do physical work in the field level to control and run. This is a level where PLCs (Programmable Logic Controller) and PID (Proportional Integral Derivative) work. The controllers use all the information as input from the sensors, switches and other input devices to make decisions on what output must be needed on the programmed task and further how the programmed task gets complete. A PID is usually integrated into the PLC’s. PID helps to keep a variable within a set of parameters. (For eg. a common industrial PID controlled device is a heater. Many systems in the manufacturing industry need to be heated. To control this heat, a PID block integrated into the PLC’s is used. When the setpoint is entered, a PID will determine when the PLC needs to turn the heater on or off to maintain a constant temperature.)
The level after the control system is known as the supervisory level. The previous level has used PLC’s while this level uses SCADA (Supervisory Control And Data Acquisition). SCADA utilizes data from the field and control level. It is used to access data and control systems from a single location. On the other hand, SCADA uses a graphical user interface or HMI (Human Machine Interface) to control the functions remotely. (For eg. Water Treatment plants will often utilize this technology to control remote water pumps in their systems.) In short, SCADA can monitor and control multiple systems from a single location. These are great for controlling and automating large areas or over long distances.
The level used after SCADA is the planning level. This level is based on the computer management system called MES (Manufacturing Execution System). MES monitors the entire manufacturing processes in a plant or factory from the raw materials to the finished products. This level allows management (ERP) to see what exactly is happening in the industry and also, allows management to make decisions based on the information. Management can adjust raw material orders or shipment plans based on the real data received from the previous levels (Field level, control system as PLC’s and SCADA).
After MES, the top-level is called ERP (Enterprise Resource Planning). This is also called a management level as mentioned in earlier point. ERP uses an integrated management system where a company’s top management can see and control their operations. ERP is usually a set of different computer applications that can see everything going on inside a company. ERP utilizes all technologies that are used in the previous levels and some more software application to accomplish its integration. This level allows the business to monitor all the activities like manufacturing, sales, purchase, finance, payroll and many others. The integration of this level promotes efficiency and transparency within a company by keeping everyone on the same page.
While developing an automated interface between the control system (PLC’s and SCADA) and the enterprise system (MES and ERP), ISA-95 standards are used. ISA-95 is an International Standard from the International Society of Automation. It is used by many large scaled manufacturers across the world.
This is how technology is used to automate the industries.
Figure 3 : Automation Pyramid
Industries using MES:
MES can be utilized for all industries due to its robust manufacturing execution software models. It supports all different manufacturing industries and processes.
MES supports complex workflows in the industry, automated data collection for high volume. It is being used in discrete, batch and continuous processes in manufacturing industries like pharmaceuticals, plastics, metals, semiconductors, electronics, medical devices, automotive, aerospace and the list go on.
Companies that are providing such enterprise systems:
Siemens, ABB, Emerson Process Solution, Rockwell Automation, Schneider Electric, Honeywell Process Solution, Mitsubishi Electric, Yokogawa Electric, Omron Automation, Danaher Industrial Ltd, etc.
