Manufacturing companies must manage materials, shipments, money, people; and the like. These companies require systems to be in place from the upper end including finance, purchasing, sales, etc. all the way down to the plant floor where machine operators produce the correct product with the correct quality standards.

At the plant floor, these systems can be handled by computers and software, spreadsheets, notepads, verbal communications, or in the mind of a person who has learned through many years of experience. Whatever the system may be, it is in place and is working, otherwise, the manufacturer would go out of business due to missed shipments, poorly handled finances, poor product quality, etc.

At the upper end, systems exist commonly referred to as Enterprise Resource Planning (ERP), Manufacturing Resource Planning (MRP), or Advanced Planning System (APS). These systems handle receiving orders from customers, group into production orders, ensure there are enough raw materials on hand, schedule the equipment to run the production orders, etc.

At the lower end, there are systems in place to control the machinery. These systems consist of sensors, push buttons, special computers to control machines, Human Machine Interface (HMIs), etc. The operator can start, stop, and control other aspects of the machine operation. These systems alone do not have any knowledge of the product being produced, raw materials being consumed, etc. without the operator making manual entries nor are these systems required to run the machine.

Typically, HMIs are local to a machine or process and don’t span across the entire facility. This is where Supervisory Control and Data Acquisition (SCADA) comes into play and commonly, but not always, is the same system as the HMIs. SCADA systems control processes locally or remotely, provide high-level monitoring, collect process data in real-time, maintain historical data, log events and alarms, etc.

Between the upper and lower end there is a layer that exists in every manufacturing company that is commonly referred to as MES. This is the system that is used to control, track, and document the transformation of raw materials into finished goods in real-time.

The primary functionality provided by an MES system includes:

• Detailed resource scheduling and status
• Dispatching production tasks and sequencing
• Traceability and genealogy
• Work-in-progress and inventory
• Ensuring quality
• Detailed maintenance management
• Work instructions and other document control
• Performance analyses

Some of these items are similar to what ERP or MRP systems provide but the level of detail needed at the plant floor is much greater than what is needed at the upper level. For example, ERP systems don’t need the details required to change over a machine to run a specific product or the steps to heat up a process prior to running a specific product.

The International Society of Automation (ISA) is an organization that sets standards for automation. One such standard is ISA-95, developed by a committee of volunteer industry experts. The ISA-95 Standard was created because the integration of business logistics systems with manufacturing systems is difficult and expensive. It provides a common nomenclature and model to describe controlling, tracking, and documenting the transformation of raw materials to finished goods.

ISA-95 uses the term Manufacturing Operations Management (MOM) to describe the space between the upper level and the lower level. Part of the ISA-95 standard specifically states content areas as: production operations management, maintenance operations management, quality operations management, and inventory operations management.