M4E #21: What is a Manufacturing Execution System (MES)?
If you are into the manufacturing world you have probably already heard about MES (Manufacturing Execution System). In summary, an MES is a software system used to track and control the process of manufacturing goods from raw materials, converting them into finished products. The following video from Flexware Innovation provides some insights regarding the functions of an MES.
Time for Insights
You may also hear about another concept: MOM. It stands for Manufacturing Operations Management. Although many times the MES and MOM terms are used interchangeably, they are not the same. Each tool has different scopes, as MES is more linked to factory floor and production operations while MOM considers business operations as a whole. Thus, it includes quality management, logistics or staff scheduling tools. An MES can also be considered as a subset of a MOM.
According to the ISA95 standard, MES are located at level 3 in the automation pyramid. You can see again M4E #14 to refresh some concepts.
Moreover, this same standard dictates what are the 11 core functions that every MES should have:
Data acquisition (typically from PLCs or SCADAs)
Work Order scheduling
Staff management
Resource management
Flow of products and batches
Product traceability and genealogy
Quality control
Process management
Performance analysis (OEE is one of the main KPIs used here)
Document management
Maintenance management (however this feature is handled many times by an independent tool called a CMMS, Computerized Maintenance Management System)