MES systems are computerized systems used in production to track and document the conversion of raw materials to finished products. They provide information that helps decision-makers understand how the current conditions in the plant can be optimized in order to improve output. MES works in real time to provide control over several elements of the production process (for example, inputs, personnel, machines and support services).
How it works?
MES unified management systems can work in several functional areas: managing product definitions throughout their life cycles, resource planning, order fulfillment and dispatching, production analysis and downtime management for overall equipment efficiency (OEE), product quality or material tracking, etc. d.
Such a system creates an “embedded” record, capturing data, events and results of the production process. This can be especially important in regulated industries, such as food and beverage or pharmaceuticals, where documentation and confirmation of processes, events and activities may be required.
The idea of MES can be seen as an intermediate step between an enterprise resource planning (ERP) system and control and assembly control (SCADA) or a process control system.
Industry groups such as the MESA (International Manufacturing Enterprise Solutions Association) were created in the early 1990s to regulate complexity and provide recommendations on how to implement MES Systems.
Benefits
These systems help you create flawless manufacturing processes and provide real-time feedback from your requirements. In addition, they provide all the important information in one source. Other benefits of successfully implementing MES systems may include:
- Reducing the amount of waste, recycling and destruction, including in a shorter time.
- More accurate collection of cost information (e.g. work, downtime, and tools).
- Increase uptime.
- Introduction of paperless work.
- Reduction of surplus due to the elimination of inventory in each case.
Varieties of MES
A wide variety of MES systems has arisen with widespread use of collected data for a specific purpose. Their further development during the 1990s led to an increase in their functionality. The Manufacturing Enterprises Association (MESA) then introduced a specific structure, identifying 11 functions that limited the scope of MES. In 2000, the ANSI / ISA-95 standard combined this model with the Purdue Reference Model (PRM).
A functional hierarchy was defined in which MES executive production systems were at level 3 between ERP at level 4 and process control at levels 0, 1, 2. Since the publication of the third part of the standard in 2005, activity at level 3 has been divided into four main operations : production, quality, logistics and maintenance.
Between 2005 and 2013, additional or revised parts of the ANSI / ISA-95 standard defined the hardware composition of MES systems in more detail, covering the methods of internal distribution of functions and the exchange of information both inside and outside.
Functional Areas
Over the years, international standards and models have expanded the scope of these tools in terms of their activities. Typically, the purpose and functions of MES systems include the following:
- Manage product definitions. This may include storage, version control and data exchange with other systems, such as production rules, specifications, resource counting, process control points, and quality data, each of which focuses on determining how to create the product.
- Resource management. This may include the registration, exchange and analysis of information about resources aimed at preparing and executing production orders that are possible and accessible.
- Planning (production processes). These actions define a production schedule in the form of a set of execution orders to satisfy production requirements, usually obtained from enterprise resource planning or specialized advanced planning systems, that ensure optimal use of local resources.
- Sending production orders. Depending on the type of production process, this may include the further distribution of batches, runs and orders for the performance of work, issuing them to work centers and adapting to unforeseen conditions.
- Fulfillment of production orders. Although the actual implementation is carried out by process control systems, MES can carry out resource checks and inform other systems about the progress of production processes.
- Production data collection. This MES function includes the collection, storage and exchange of process data, equipment status, information about materials and production logs, either in a file cabinet or in a relational database.
- Production performance analysis. This is to obtain useful information from the raw data collected about the current state of production. These include past performance (WIP) and performance reviews (such as overall equipment performance or any other similar metric).
- Production track and trace. This is the registration and extraction of related information in order to present a complete history of sales, orders or equipment. This area is especially important for industries related to the health sector. This is, for example, the release of pharmaceuticals.
- Digitization of complete data from the logs to the interface of digital devices using the edit lock function, as well as the output of data from SCADA to a common data bank.
Communication with other systems
The MES production management system integrates with the ISA-95 (previous Purdue model model, “95”) with multiple relationships and relationships. The set of systems operating at ISA-95 level 3 can be called Production Operations Management Tools (MOMS). In addition to MES, there is usually a laboratory information management system (LIMS), warehouse management (WMS) and computerized service management system (CMMS).
From the point of view of MES, possible information flows are:
- in LIMS: requests for quality testing, sample samples, data from statistical processes;
- from LIMS: results of quality tests, product certificates, test results;
- in WMS: requests for material resources, definition of materials, delivery of products;
- from WMS: availability of materials, phased lots of materials, shipment of the product;
- in CMMS: equipment that works with data, its purpose, service requests;
- from CMMS: maintenance progress, equipment capabilities, maintenance schedule.
Communication with level 4 systems
Examples of systems operating at ISA-95 level 4 are product life cycle management (PLM), enterprise resource planning (ERP), customer relationship management (CRM), human resources (HRM), process execution system (PDES).
From the point of view of MES systems, examples of possible information flows are:
- to PLM: production test results;
- from PLM: product definition, operation accounts (routes), electronic work instructions, equipment settings;
- to ERP: production results, produced and consumed materials;
- from ERP: production planning, order requirements;
- in CRM: information tracking;
- from CRM: product complaints;
- to HRM: personnel efficiency;
- from HRM: staff skills, staff availability;
- to PDES: test results;
- from PDES: definition of production flow, definition of experiments (DoE).
In many cases, Middleware Enterprise Application Integration (EAI) systems are used for messaging between MES and Level 4. A common data definition, B2MML, was defined in the ISA-95 standard to associate MES with the above level 4 systems.
Communication with systems of level 0, 1, 2
ISA-95 Layer 2 systems include supervisory control and data acquisition (SCADA), programmable logic controllers (PLC), distributed control systems (DCS) and batch automation systems. The information flows between MES and these process control systems are approximately the same:
- to PLC: work instructions, recipes, settings;
- from PLC: process values, alarms, corrected control points, production results.
Most MES systems include connectivity as part of their product offering. Direct communication of plant equipment data is established by synchronization with a programmable logic controller (PLC). Often, data is first collected and diagnosed for real-time control in a distributed control system (DCS) or supervisory control and data acquisition (SCADA). In this case, MES are connected to these level 2 systems to exchange data on the floors of the plant.
The industry standard for connecting to manufacturing elements is OLE for Process Control (OPC). But now, the industry standard has begun to switch to OPC-UA. Modern OPC-UA compatible systems will not necessarily work only in the Microsoft Windows environment; they are designed to run on GNU / Linux or other embedded systems. This reduces the cost of SCADA systems and makes them more open with reliable security.
Manufacturing companies use MES systems on the market to track raw materials from the factory to the final state. When used correctly, this system can reduce waste, provide more accurate reflection of costs, increase uptime and reduce the need for some equipment. There are several basic facts that everyone should know about production execution systems.
They manage product definitions.
Any experienced manager knows that even the slightest change in material can completely change the finished condition of the product. A deficiency or excess can lead to serious changes in the quality of the product. All this can lead to additional costs.
The main functions of MES systems allow you to actively track the components that make up your product. They give you the opportunity to set tough parameters for your production equipment, which ultimately reduces waste and saves money.
They adequately evaluate production resources (with some help)
As mentioned above, MES-class systems can determine the exact amount of material needed to create a product, which allows you to create a clear definition of the product and maintain its integrity. In addition, you will always have an idea of what your production resources are. This category includes everything from accounting for physical materials to knowing the number of machines serviced or the availability of labor required to complete work. MES in conjunction with the APS (Advanced Planningand Scheduling) system have the ability to really predict the product completion dates for 100% of all the resources that you have in the distribution.
They can be integrated with other production systems.
Alone, production execution systems often have the ability to plan production processes, but at the “infinite capacity” level and, therefore, can technically work as stand-alone planning software. However, they tend to function better when used in conjunction with other manufacturing processing software such as APS, so that end constraints can also be reflected for more accurate and optimized planning.
APS defines a production schedule as a set of work orders to meet production requirements typically derived from enterprise resource planning (ERP), which in turn helps to mainly use resources.
They provide an analysis of production efficiency.
Once a product has begun to work its way into production, MES can generate reports based on its current status. Work in progress, various historical indicators and all other performance data can be tracked using this system.
Production Tracking
When a product finally leaves the production line, MES monitors all data regarding it and saves it for future use. Moreover, the system will not only provide you with an organized digital journal of your product data, it will also be able to combine this information for future reports. Regardless of internal or external goals, you will have current updated data on the speed of your production processes, which will ultimately help to make more profit.
In combination with APS systems, MES can be incredibly useful for any manager who wants to increase production time and speed. Adequate resource management, production planning and product tracking will allow any company to increase production and reduce waste in both skillful and calculated ways.
MES and APS - together or separately?
Before you review MES systems, you should understand how they interact with other similar tools. So, APS (Advanced Planning & Scheduling) is its own software category, such as ERP or MES. APS covers strategic, tactical and operational planning. The last, operational use case is considered many times as the core of the APS. Here, planning is the development of an ultimate goal on a daily basis. Its essence is to develop possible plans to minimize excessive stocks and reduce lead times. There are many APS providers you can find these days.
On the other hand, the MES system executes commands and controls. There is MES software both without any planning functions, and with limited functionality. In any case, the possibilities are not as extensive as in pure APS software. In the annual MES Product Review, the proportion of FCS functionality with MES software is increasing. Since it is transactional software, it is quite difficult to implement all the extensive planning functions in this context. Planning and forecasting require modeling of various scenarios and should not automatically influence the execution of tasks.
With tight integration of MES and APS systems (in the form of a closed loop), all the rich functionality of APS are used without any restrictions. If this system supports multi-site planning and a powerful Internet, the entire supply chain can be planned, executed and monitored in real time - globally without geographical restrictions. For example, when you start an operation (work phase) in China, a planner in the USA can see the order execution in real time. Also, the seller can enter the MES / APS application via the Internet and see when the product will be sent to the client, without phone calls and letters.
MES and MOM: what is the difference?
Terminology can be confusing in the software industry, especially if you are just starting to study this subject. Unfortunately, this observation is true for software in industry and production. Many different systems have been used over the years, but only 2 abbreviations cause confusion:
- MES is a production execution system.
- MOM - production operations management.
To understand the difference between them, it is necessary to conduct a comparative analysis of the MES systems (PDF table) and MOM. We can distinguish their similarities and differences during the description.
As mentioned above, MES was first used by AMR in the 1990s, displacing Computer Computing Manufacturing (CIM), first adopted in the late 1980s. This happened before many standards in the industry were established (such as ISA-95), and, of course, much earlier than ERP took root as the main IT backbone for most global manufacturing companies.
Many early MES systems were purpose-built closed. Because of this, they lacked the flexibility necessary to adapt to changing business needs. This led to many early implementations having very lengthy calculations and often creating an implementation process that seemed to have no end. For these reasons, when introduced into production, the MES system initially gained a reputation as an expensive and risky tool that often did not achieve the initial ROI goals.
At the same time, much work continued to be carried out in the field of industrial automation, and a number of package-level standards (such as ISA-88 and ISA-95) appeared. They defined the term Manufacturing Operations Management (MOM). In this system, detailed activities and business processes were identified, including production, quality, service and inventory.
MOM development
New market conditions have led to the appearance of developers who want to rebrand and separate from products of the past, namely from MES. Many of them adopted the term MOM and referred to their proposals as a new solution. They offered the flexibility and scalability necessary for the system to become a true enterprise application, including:
- architecture based on customizable and extensible platform;
- standardized integration with ERP;
- standards-based integration with industrial automation;
- standardized production data model;
- wide opportunities - model, visualization, optimization, updating and coordination of production business processes around the world;
- event management - the ability to collect, summarize, analyze and respond to production events in real time.
Despite this trend, previous designs have not been forgotten. Leading suppliers of MES did not abandon their product. Instead, they redesigned their systems and endowed them with capabilities not inferior to the functionality of MOM.
So what is the difference?
Today, the acronym MOM usually refers to business processes, not software. The designation “MOM Platform” (MOM Solution) is most often used to differentiate from older MES solutions and has the capabilities listed above.
MES is still used in most cases. Sometimes it may have similar capabilities with MOM, but, unlike it, is developing at a faster pace.
MES Examples
Three such systems are leading in Russia today. All of them are designed for better production management, but are designed for small-scale variety. At the same time, differences between them are present.
MES-system "FOBOS" is used in medium and relatively large engineering industries. Its main functions are internal workshop management and planning. It necessarily integrates with the ERP-system (or “1C: Enterprise”), redirects all received data to it.
YSB.Enterprise was created for the wood industry. In addition, it has some features, due to which it is more suitable for small enterprises (such where only 1C is no longer enough). MES-system has too few specific and necessary functions for full-fledged work, but at the same time there are additional options in it, including sales management and accounting.
PolyPlan has an even smaller set of MES functions, but at the same time it is presented as a tool for operational calendar planning in the field of mechanical engineering (for flexible and automated production). The cost of this type of MES system is the lowest.