A manufacturing execution system is a software-based system used to manage manufacturing and production operations in factories. The system uses a network of computers to monitor and help manage events taking place on the factory floor. A manufacturing execution system is considered a level-three system in the ISA-95 standard for control systems. As such, it typically works with other level-three systems, such as a warehouse management system or laboratory information management system.
In order to do its job, a manufacturing execution system needs information. This information is collected from the factory floor using machine monitoring sensors and data collections terminals. Information from these sources is sent to a central computer for processing. Using this information, the manufacturing execution systems sends real-time instructions to the devices on the floor that adjust the production process accordingly.
Early data collection systems created in the 1980s were the first step toward dedicated manufacturing execution systems. In the following decades, a number of systems were developed to serve as manufacturing execution systems. Many of these had overlapping functions that resulted in less efficiency. To get rid of overlapping functions, the Manufacturing Enterprise Solutions Association defined 11 functions that could be performed by a manufacturing execution system.
The ultimate purpose of manufacturing execution system software is to improve productivity by making the process as speedy and efficient as possible. The less time it takes to make the product, the more copies of the product a company can produce in a day. Therefore, faster production means more income for the company.
Different manufacturing execution systems stress different functions and offer different levels of control over the production process. The choice to use one manufacturing execution system over another depends on the needs of the company. Some typical functions of a manufacturing execution system include execution and dispatching of production orders, analysis of production performance, and management of resources used in production.
In the early 2000s, ISA-95 merged the Manufacturing Enterprise Solutions Association standards with standards from the Purdue Reference Model to create a functional hierarchy of software to monitor production and manufacturing. All ISA-95 compliant systems have standardized interfaces to allow them to communicate with each other. ISA-95 uses models to determine which information should be exchanged between various systems. ISA is an organization founded in 1945 and based in North Carolina in the U.S. In addition to developing standards, ISA also trains, certifies, and hosts conferences for automation professionals.