What’s the Difference Between MOM & MES?

Posted by Andrew Hughes on November 16, 2015

Find me on:

I would like to bring to your attention something that has been on my mind for at least 20 years (I know, I do not live a very interesting life!). A topic that is mentioned quite often at LNS Research, what the difference is between MOM and MES?

What Is MOM & What Is MES?

The terms Manufacturing Execution System (MES) and Manufacturing Operations Management (MOM) are often used interchangeably and define a different functional space to each and every manufacturing professional:

  • Some think they are synonymous and interchangeable
  • Some think MES is a subset of MOM
  • Some believe we should get rid of one and stick to a single term
  • Some are just confused (this is the biggest group)

Having discussed it in the LNS Research team we have decided that we will define our understanding of the terms and henceforth will be clear in our use of them, so that confusion is not increased any more.

We shall use the term Manufacturing Operations Management (MOM) to cover the ISA-95 Level 3 architecture and functionality as in the simplified diagram shown here. This will include extensions or variations on the ISA-95 model. We foresee changes in the model as manufacturing gets integrated into the Industrial Internet of Things (IIoT), but that discussion is for another day.

The term Manufacturing Execution Systems (MES) is used in so many ways that it is hard to come up with an agreed upon definition. However, we do not want to exclude its use in normal discussion as many manufacturers refer to MES systems used in operations and vendors use MES in naming products. Therefore we will use MES in all its casual meanings when appropriate, and where there is no confusion. Where there might be confusion we will tend to clear it up by using the term MOM as defined above.

Where a vendor uses MES as a product name, e.g., ACHCo MES we will respect that naming even if the product is a full MOM solution. If a vendor or end user uses both terms in their daily life, we will try to clear this up for our readers by using MOM in the restricted ISA-95 definition while being looser with the use of MES.

We hope this clarification will help everyone in future discussions with LNS Research and elsewhere. Now back down to some MOM research…

Gain a year of free access to new research in our IoT Research Library by completing a survey.IIoT & Big Data creates a revolution in manufacturing

Categories: Manufacturing Operations Management (MOM), Manufacturing Execution System (MES), Industrial Internet of Things (IIoT)