MES and ERP Software: A Strategic Complementarity for Industrial Integrators

“We already have an ERP — do we really need an MES?”
This question comes up very frequently among manufacturers. It often reflects a partial view of the industrial information system, in which ERP is perceived as the central tool, expected to cover all enterprise needs on its own.

For integrators, it is essential to move beyond this apparent opposition. ERP and MES are not competitors — they are complementary. Together, they form a coherent partnership capable of covering both enterprise-wide management and the operational execution of production.

ERP: A Tool for Enterprise Management and Organization

ERP (Enterprise Resource Planning) systems are designed to manage the enterprise as a whole. They structure purchasing, sales, finance, inventory, and production planning. ERP forms the organizational backbone that supports strategic decision-making and medium- to long-term flow management.

In an industrial context, ERP relies on data entered by employees or provided by other application systems such as MES, PLM, or CMMS. It consolidates this information to deliver a global view of business activity.

However, ERP is not designed to manage the shop floor in real time. It operates primarily at the organizational and decision-making levels. It does not collect production data directly at the source, nor does it provide the tools required for detailed execution of shop-floor operations.

For integrators, this limitation is a key point to clarify: ERP is essential, but it is not sufficient on its own to effectively manage production.

ERP and MES: A Natural and Complementary Partnership

ERP and MES share a large set of common data related to equipment, work orders, product references, routings, bills of materials, and batches. However, each system uses this information at a different level.

MES software is positioned as the system responsible for collecting, structuring, and consolidating shop-floor data, as close as possible to operators and machines. It transforms this data into actionable information and feeds it back to the ERP, which can then perform its management, planning, and enterprise-level control functions.

For integrators, this complementarity is a powerful lever. It enables the design of coherent architectures in which each system fully plays its role, without redundancy or unnecessary data re-entry.

Different Time Scales and Usage Patterns

One of the main differences between ERP and MES lies in their relationship to time. MES is directly connected to production equipment and processes data at the second — or even millisecond — level. It is designed to continuously monitor production execution.

ERP, by contrast, operates on broader time horizons. It consolidates information at the hourly, daily, or weekly level to manage factory and enterprise operations.

In many organizations, production data is still collected manually by operators, on paper or through delayed entry. Managers must then retrieve, consolidate, analyze, and calculate indicators. This process is time-consuming, error-prone, and often results in after-the-fact analysis — sometimes one day later or more.

For integrators, MES provides a direct response to this challenge. It eliminates these temporal gaps and restores responsiveness to industrial performance management.

MES: The Real-Time Tool Serving the Shop Floor

MES software focuses exclusively on the factory and production or packaging shop floor. Its objective is to digitalize all production operations and deliver the right information, in real time, to the right person.

It supports production execution through operator guidance, enables continuous improvement initiatives, and digitizes activities related to work orders, quality, maintenance, and traceability. MES also supports shop-floor scheduling and provides machine-level access to documentation such as procedures, photos, and videos.

For production managers and supervisors, MES significantly simplifies analysis and control. Indicators are calculated automatically, reports are generated instantly, and action plans can be built on reliable, objective data.

For integrators, MES thus becomes a unifying tool at the intersection of production, quality, maintenance, and industrial engineering.

Data Granularity Tailored to Each System

ERP and MES serve different purposes, which is reflected in the level of data granularity they handle. MES works with fine-grained, contextualized data tied to the actual execution of operations. ERP uses this data in an aggregated form to manage inventory, costs, lead times, and customer commitments.

In a well-designed architecture, both systems feed each other. MES retrieves work orders, target quantities, and, when required, bills of materials or batch data from ERP or production planning systems. It uses this information to build shop-floor schedules and deliver work instructions to operators.

In return, MES sends execution data back to ERP: work order progress, quantities produced, machine time, labor time, performance indicators, production events, consumption data, and traceability elements. ERP can then manage inventory, orders, and financial flows based on reliable, up-to-date data.

MES–ERP Integration at the Heart of Integrator Value

Modern MES solutions provide standard bidirectional integration mechanisms with ERP systems, based on proven technologies such as web services, structured files, or application interfaces.

For integrators, this interfacing capability is essential. It enables MES solutions to be adapted to existing environments and supports the wide variety of ERP systems used by manufacturers.

Relying on an MES solution such as Aquiweb, already integrated with many leading ERP platforms, helps secure projects and reduce integration-related risks.