MOM vs MES: Operation Management vs Execution System

What is the difference between MES and MOM?

Lately, you hear the term MOM being used more and more often, and also very often in combination with MES. But is there really a difference between MES and MOM? And why are these two terms used together? In this article, you can read the answer.

Manufacturing Execution Systems

A Manufacturing Execution System (MES) emerged in the middle of the ’80s. It developed as the intermediate layer between PLC/SCADA and ERP.

The Manufacturing Execution System (MES) receives production orders from the ERP system.  It ensures that the various production departments are provided with the correct information. Via PLC/SCADA, MES collects data from production and makes them available to the ERP system. You can read more about MES on this page (Dutch).

The first MES solutions were not yet as comprehensive

The companies that started working with MES developed a demand for certain functionalities in MES. The desire to have employees who are directly involved in the production process work in a single system contributed to the fact that MES suppliers continued to expand their MES on the basis of customer demand. Functionalities were added that could be related to quality, stock, and maintenance. MES also communicates with ERP in these areas.

In the case of stock, it initially concerned specifically the stock on the production floor. But the MES supplier soon realized that it had many advantages to offer WMS functionality as well. The WMS became an extension of the MES and could be purchased stand-alone at a certain point. Nowadays, the term MOMS is used to quickly indicate what kind of application it is. From this, you can immediately deduce that the application goes beyond purely production-related functionality.

MOM stands for Manufacturing Operations Management and aims to produce with as little waste as possible. MOMS software helps with this and is not limited to the production process.

MOM, MES, and the ISA-95 model

If you look at the ISA-95 model (figure 1), you will see that Level 3 is called the Manufacturing Operation Management level. Figure 2 shows that MES, WMS, LIMS, and MMS are also part of Level 3. MES and WMS have reached a mature level for a number of MOMS suppliers. LIMS and MMS are often less extensively integrated into MOMS, there are good reasons for this, but more about this in the following blogs.

You can see more about the different MES solutions in this video (Dutch).