When to Implement MES Before PLM: A Manufacturer’s Guide

At First Resonance, we often hear from manufacturers who are weighing whether to prioritize PLM or MES in their digital journey. In this guest blog from Tech-Clarity, Julie Fraser’s perspective offers valuable guidance in framing that decision. While traditional MES has long served as the backbone of factory execution, we see modern manufacturers evolving toward a more holistic Factory OS that integrates execution with quality, scheduling, and connectivity across engineering and operations. From our experience, establishing strong product data foundations through PDM and PLM is essential to unlock this next generation of factory automation. Julie’s insights provide a timely lens into this important discussion.

When Is MES Best Implemented Before PLM?

A manufacturer's specific challenges will determine which software solutions deliver the most value and are logical to implement first. Over time, companies typically need to integrate a set of enterprise applications. Often, deploying them one at a time is the only feasible path. For many manufacturers, deciding whether to implement MES or PLM first is a critical strategic decision.

We cannot answer the specific question of whether MES or PLM is the logical next step to digitalizing your business in this blog post. Still, we will help ensure you’re asking the right questions and making considered calculations. This post is meant to deliver some food for thought for a manufacturer deciding when factory software is the top priority to implement before PLM.

What is MES and Why It’s Crucial

Tech-Clarity defines Manufacturing Execution Systems (MES) as systems that deliver information to optimize production activities from order launch to finished goods. MES guides, initiates, responds to, and reports on plant activities as they occur. To do so, MES puts into context a wide array of real-time and historical data from both operations technology (OT) and information technology (IT). MES can deliver mission-critical information about production activities to the rest of the product lifecycle, enterprise, and supply chain via bi-directional communications. MES often includes adjacent functions such as quality, scheduling, in-house logistics, and asset maintenance to comprise Manufacturing Operations Management (MOM), as the ISA-95 Model envisions.

In that definition, you will see that MES does what other systems typically do not do well. ERP has historically been the core for financials and inventory management. It is good at linking together all the business basics in a seamless environment. ERP often has a plant floor module, but that is primarily intended to send inventory signals back up to the office, not to guide production work and employees.

The core of PLM is Product Data Management (PDM). PDM enables development teams to control, access, and share their product data. It provides companies with a single source for product designs so all parties, internal and external, work from the same product definition. PLM extends that by supporting more product-related data and processes across the enterprise and the product's life. PDM’s CAD models, configurations, visualizations, and bills of materials (BOM) management provide the product data backbone. PLM goes further by providing a process planning framework to feed manufacturing. (See Five Ways to Get More Business Value from Your PDM.) However, these are not typically detailed or easy for production to use. Neither PDM nor PLM is intended to drive or track manufacturing execution. PLM’s quality function often includes quality planning, FMEA, nonconformance, and corrective action tracking. Yet PLM is not designed to integrate into actual processes, equipment, and metrology for real-time test, inspection, and disposition of materials and products.

A modern MES or factory software system might go by another name, and often includes execution, quality, and scheduling. Some factory software systems extend to include all of that plus functions such as purchasing, inventory, and supplier management. For companies moving from prototype to production, this can bridge the gap while providing critical operational control and traceability without the weight of a complete ERP rollout.

Basics for Running a Manufacturing Business

Scaling from a development business to a manufacturing business involves changes in people, processes, data, and technology. At some point in this journey, nearly every manufacturer will need software for product, production, and business support. For years, PLM, MES, and ERP have been basic software suites for organizing, managing, and delivering the data needed to run a manufacturing business.

Innovation – Most companies start with a great idea and then do R&D for products and processes to make those products reliably. PDM is suitable for product data, and PLM can support both product and process engineering. However, feedback on actual production results about both the product and the process from the shop floor can be essential to developing a complete understanding and driving continued innovation to get to scale and increase profits.

Finances – Companies need to understand their financial situation, and ERP is central for this. It links prices to materials and resources expended, as well as to products and orders sold.

Ecosystem – Manufacturers have both customers and suppliers, and some also have contract manufacturing and distribution partners. ERP, a specialized CRM, or SRM are the usual ways to manage these. However, those systems may also need product information from PDM and product “actuals” such as the as-built materials or ABOM, quality results, or measurements from the factory system.

Orders – Customer orders nearly always live in ERP or CRM. In contrast, MES and factory systems typically manage detailed production orders and track them as they move from raw materials to finished goods for the customer.

Products – This is the strength of PDM and PLM. They manage and validate product data, including variants, complex configurations, ECOs, revisions, and specifications. Understanding and communicating these product details is crucial, and PLM can do that across systems, the enterprise, and the supply chain.

Inventory – ERP does this, but many companies have specialist supply chain software. Some of today’s best factory systems can also manage inventory levels, movement, and schedules at a detailed level inside the manufacturing facility.

Production – Guiding, executing, and tracking production end-to-end is complex, and precisely what MES does. Our research shows that pulling into context the varied data from machines, IoT, metrology, and IT for production, scheduling, maintenance, and in-plant inventory can take inordinate time, effort, and resources without a strong factory-wide software system.

Quality – Ensuring quality and keeping the cost of quality low starts with R&D defining the product and process well in PDM or PLM. It then moves into procurement with supplier quality, and the plant for final product quality. Every department and system should support quality.

Resources – People, tooling, equipment, direct and indirect materials, energy, and more go into manufactured products and dictate their profitability. Managing these can involve specialized systems, but an expanded modern factory software system with inventory management, scheduling, and dispatching can ensure they all come together effectively.

MES Strengths

Where does MES shine? What core capabilities does today’s factory software have that other systems typically do not?

Real-time visibility into and management of production operations, end-to-end: This is important for fast-moving industries and experimental production runs.
Detailed serialized traceability: MES can trace every material and component into every unit of every product, filling in the crucial information from incoming materials to shipped products, typically with minimal human intervention.
Regulatory and customer compliance: Modern factory systems can automatically create sign-offs and escalations, enforce SOPs, and document issues and fixes.
Guidance: When a company has manual assembly or production operations and people need clear guidance, work instructions, or error-proofing, modern MES can help even less experienced workers perform well.
Feedback on actuals: It can answer questions such as: Do the as-built measurements match the specs? If not, where are they off? How long did each operation take? How about the entire order? How much material went in? Were there challenges executing as planned?
Inventory tracking on the plant floor: MES shows how much of what is where at any given moment and its disposition, whether using Lean or traditional approaches. When the factory software includes purchasing and warehouse control, the inventory view can connect directly to supplier orders, receipts, and material use. This is especially valuable in high-mix or fast-changing environments where engineering and production both need live material status.
Quality control: error-proofing, inspection processes, non-conformance recording, disposition of materials for rework or scrap, and in-context information to support root cause analysis for both processes and products.
Operations data management: MES puts data from across a plant or several plants into a usable context, associating IIoT and machine data with the order, materials, operator, quality issues, and conditions, for example.
Actionable insights: According to our research, Making Manufacturing Analytics and AI Matter, data is the #1 challenge for AI success. The context from modern factorywide software can enable analytics and AI to perform valuable functions on the diverse data from manufacturing. MES’ structured data helps AI answer questions such as “When will that problem recur? Are problems emerging in these parts? Is equipment, people, materials, or methods the root cause of this issue?”

Questions for Deciding Whether MES is Next

That’s quite a bit of information. Consider the priority of these capabilities for your business at this time. This must be an executive and cross-disciplinary exercise, as the product innovation and engineering teams will also have specific needs for PDM and PLM. Those outside of engineering may not understand all that product innovation teams need to succeed. Similarly, those outside the manufacturing operation may not understand the unique needs of the factory. So be sure everyone is at the table to set priorities.

Most companies start as R&D operations, so moving beyond engineering into manufacturing may be less comfortable or familiar. The ability to scale and grow a company relies heavily on scaling into production, where factory systems manage and optimize manufacturing capabilities.

Here are some questions to help you and your team decide whether to implement MES next.

Where are our most severe pain points?

If your product vision is getting market traction and early customers are happy, it might be time for MES.

Modern factory-wide software may be the cure if production is problematic, cumbersome, or difficult to staff.

If quality is not meeting specifications or the cost of quality is too high, MES might help.

If employee turnover on the plant floor is high, a modern factory system can help provide consistency and a better work environment.

Where are we in our development as a business?

End-to-end factory software becomes essential when a company moves its products beyond pilot into production.

When the company has more than one product or variant, MES can manage the exponential complexity of the manufacturing operation and support workers.

Do we have customer or business success requirements that a factory system can best solve?

Factory operations software can deliver quick value if your business needs complete traceability or regulatory compliance through a complex process with many steps and interdependencies.

If design of experiments (DoE) or clear visibility to results of process and product options are needed to determine feasibility to both meet customer needs and make a good profit, MES can do that.

Do we have the basic inputs for a factory system to do its job?

Can we reliably get information on orders and materials?

Is product data controlled with accurate release timing, BOMs, and versions and revisions managed?

What is our priority or basis of competition?

If you intend to compete on cost, quality, reliability, or timeliness of order delivery, modern factory software might be your secret weapon.

If customers come in to inspect your operation in selecting or keeping you as a supplier, having an end-to-end factory system can impress them.

Getting It All

If a company has basic product data and engineering processes under control - at least at the PDM level – it may be time for factory software. Yet, if your company needs software to support advanced engineering processes, PLM might be next.

Final quality, consistency to meet specifications, compliance, cost of goods sold, and getting orders out on time heavily depend on manufacturing running well. For companies without ERP, a modern MES that handles purchasing, inventory, and planning, along with execution and quality, can be valuable. This can speed readiness for scale and delay the need for a full ERP.

This is why it is crucial to include executive management with a purview across all business disciplines to arbitrate the conversation. These enterprise application priority decisions must align entirely with the business strategy and needs. Modern factory-wide MES is the next logical step for some companies, and we hope this helps them make a good decision.

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