MES Software: Vendors, Features & Costs Compared 2026
MES software compared: vendors, functions per VDI 5600, costs (cloud vs. on-premise) and implementation. Honest market overview 2026.
By Mark Kobbert · Last updated: April 2026
What is SCADA?
SCADA (Supervisory Control and Data Acquisition) is a software and hardware architecture that monitors and controls physical processes in real time. It reads sensor data from PLCs and RTUs, displays it on operator screens (HMIs), logs alarms, and allows operators to send commands back to the equipment.
SCADA originated in utilities (power grids, water treatment, pipelines) in the 1960s, where a central control room needed to supervise geographically distributed equipment. In manufacturing, SCADA serves the same purpose at a smaller scale: one central screen showing the state of multiple machines or process lines.
In the ISA-95 automation pyramid, SCADA sits at Level 2 (monitoring and supervisory control), directly above the PLCs at Level 1. The MES sits at Level 3 (manufacturing operations management). This distinction matters because it defines what each system does and does not do. SCADA tells you "the press is running at 280 bar and 42 °C right now." The MES tells you "this press has produced 4,200 good parts against an order of 5,000, with an OEE of 72 %, and is 35 minutes behind schedule."
What are the 5 core components of a SCADA system?
| # | Component | What it does | Typical products | In manufacturing context |
|---|---|---|---|---|
| 1 | RTU / PLC (field devices) | Remote Terminal Units or PLCs read sensors (temperature, pressure, flow, position) and execute control logic. They are the interface between the physical process and the digital world. | Siemens S7-1500, Allen-Bradley ControlLogix, Beckhoff CX series, Wago 750 series. | Every machine on the shopfloor has a PLC. SCADA reads data from these PLCs. An MES like SYMESTIC can also connect to PLCs directly via OPC UA or digital I/O gateways, bypassing the SCADA layer entirely. |
| 2 | Communication network | The data transport layer between field devices and the SCADA server. Protocols include Modbus TCP, Profinet, EtherNet/IP, OPC UA, and (for remote sites) cellular or satellite links. | Industrial Ethernet switches (Siemens Scalance, Hirschmann), OPC UA servers. | In a single factory, the network is typically industrial Ethernet. For multi-site operations, the communication challenge is why cloud-based systems (like a cloud MES) have an architectural advantage over on-premise SCADA. |
| 3 | SCADA server (master station) | The central software that polls data from all field devices, stores it in a historian database, evaluates alarm conditions, and serves the data to operator screens. | Siemens WinCC, Wonderware (AVEVA) InTouch, Ignition by Inductive Automation, GE iFIX, COPA-DATA zenon. | The SCADA server is a local application, running on dedicated hardware in the plant's server room. This is one key architectural difference to a cloud MES, which runs on cloud infrastructure and requires no local server. |
| 4 | HMI (Human-Machine Interface) | The operator screens that display process data in real time: synoptic diagrams, trend charts, alarm lists. Operators use the HMI to monitor the process and send manual commands (start/stop, setpoint changes). | Siemens Comfort Panels, Beckhoff CP3xxx, web-based HMIs in modern SCADA (Ignition Perspective). | SCADA HMIs show the machine state. MES shopfloor monitors (like SYMESTIC's web-based dashboards) show production progress, OEE, and order status. Different information for different questions. |
| 5 | Historian (data archive) | A time-series database that stores process data for long-term analysis. Historians are optimised for high-frequency data (e.g., 1-second intervals for hundreds of tags). | OSIsoft PI (now AVEVA PI), Wonderware Historian, InfluxDB, TimescaleDB. | The historian stores raw process data. The MES process data module also stores process data, but contextualises it: linked to the order, product, machine, and shift. Raw data without context is hard to analyse. Contextualised data enables root cause analysis. |
How does SCADA differ from MES and DCS?
SCADA, MES, and DCS are three systems that coexist in manufacturing but serve different purposes at different levels. The confusion arises because all three display data on screens and all three connect to machines. The differences are in scope, purpose, and the questions they answer:
| Dimension | SCADA | MES | DCS |
|---|---|---|---|
| ISA-95 level | Level 2: Supervisory control | Level 3: Manufacturing operations management | Levels 1–2: Control + supervisory (integrated) |
| Primary question | "What is the machine doing right now?" (process state) | "How is production performing?" (OEE, output, schedule adherence, quality) | "How do I keep this continuous process within specification?" (closed-loop control) |
| Data type | Process variables: temperature, pressure, flow, speed, position. High frequency (seconds to milliseconds). | Production KPIs: OEE, cycle counts, downtime reasons, order progress, defect rates. Event-driven (per cycle, per order, per shift). | Same as SCADA, but with integrated control loops (PID controllers). Tightly coupled to the process. |
| Scope | Equipment-level. Monitors individual machines or process sections. No concept of "orders" or "products." | Plant-level to enterprise-level. Tracks orders, products, quality, schedules across multiple machines and lines. Knows the production context. | Process-level. Controls a continuous or batch process (e.g., a chemical reactor, a brewing system). Tightly integrated, proprietary. |
| Typical industry | Utilities (power, water, oil & gas), discrete manufacturing with legacy automation. | Discrete manufacturing (automotive, electronics, metal, plastics, food packaging). | Process industries (chemicals, refining, pharmaceuticals, power generation). |
| Architecture | Client-server, on-premise. Central SCADA server in the plant. | On-premise or cloud. SYMESTIC is cloud-native on Microsoft Azure, accessed via browser. No local server required. | Proprietary, on-premise. Tightly integrated hardware and software from a single vendor (Siemens PCS 7, ABB 800xA, Emerson DeltaV). |
| Relationship | SCADA feeds data to the MES. The MES consumes SCADA data (process parameters, alarms) and adds production context (order, product, shift). | MES receives data from SCADA or directly from PLCs. In modern architectures, MES can bypass SCADA entirely by connecting to PLCs via OPC UA. | DCS replaces both PLC + SCADA in process industries. An MES can sit on top of a DCS to add production management capabilities. |
The practical question for discrete manufacturing: Do you need a SCADA system to use an MES? No. In many SYMESTIC implementations, the MES connects directly to the PLC via OPC UA or to digital I/O signals via a gateway. At Brita, digital machine signals are captured directly. At Neoperl, SPS alarm data flows directly into the MES for alarm correlation. SCADA is not a prerequisite for MES. Both can coexist, but neither depends on the other.
Where does SCADA end and MES begin?
The boundary is clearest when you look at what each system knows about:
| Information | SCADA knows? | MES knows? | Why it matters |
|---|---|---|---|
| Machine running/stopped | ✓ | ✓ | Both know the machine state. |
| Process parameters (temp, pressure) | ✓ | ✓ | Both can capture process data. MES links it to order context. |
| Alarms | ✓ | ✓ | SCADA shows alarms. MES (alarms module) correlates alarms with downtimes and quality defects. |
| Which order is running | ✗ | ✓ | SCADA has no concept of production orders. The MES maps every cycle to an order. |
| Which product is being made | ✗ | ✓ | Same. SCADA sees "machine running." MES sees "machine running order #4712, product XYZ, 3,200 of 5,000 parts complete." |
| OEE | ✗ | ✓ | OEE requires planned production time, good/reject counts, and ideal cycle time. SCADA does not track these. The MES does. |
| Downtime reasons | Partial | ✓ | SCADA can detect that the machine stopped. But classifying *why* (setup, breakdown, material shortage, planned maintenance) is an MES function. |
| Schedule adherence | ✗ | ✓ | SCADA does not know the production schedule. MES compares actual output to planned output in real time. |
| Traceability (serial/batch) | ✗ | ✓ | SCADA does not track which unit was produced when. MES links every unit to machine, process parameters, and order. |
FAQ
Can SCADA calculate OEE?
Not natively. SCADA can detect machine states (running, stopped, idle) and count cycles. But OEE requires additional context that SCADA does not have: planned production time (from the schedule), ideal cycle time (from the product master data), and reject counts (from quality inspection). Some SCADA vendors have added OEE dashboards as add-ons, but these require manual configuration of the missing context for each machine and product. An MES like SYMESTIC calculates OEE automatically because it has all three data layers: machine state from the PLC, order context from the ERP, and quality data from the production metrics module.
Is SCADA becoming obsolete?
No, but its role is changing. In utilities and process industries, SCADA remains essential for real-time process control and safety. In discrete manufacturing, the monitoring functions that SCADA traditionally provided (machine state visualisation, alarm handling) are increasingly handled by MES or IIoT platforms that connect directly to PLCs. The trend is not "SCADA disappears" but "the MES absorbs the Level 2 monitoring functions that discrete manufacturers need, and SCADA remains in industries where real-time supervisory control of continuous processes is the core requirement."
Does SYMESTIC replace SCADA?
For discrete manufacturing, SYMESTIC replaces the need for a separate SCADA system in many cases. It connects directly to PLCs via OPC UA and to machines via digital I/O gateways, captures machine states, process parameters (process data module), and alarms (alarms module). It adds the production context (orders, products, schedules, KPIs) that SCADA cannot provide. For plants that already have a SCADA system, SYMESTIC can sit on top of it and consume SCADA data as an additional data source. At Carcoustics, the OT integration used IXON IoT devices and MQTT to connect 500+ machines. No SCADA layer was required.
What is the difference between SCADA and a historian?
A historian is one component of a SCADA system (component #5 in the table above). It stores time-series data long-term. Some historians (like OSIsoft PI / AVEVA PI) have become standalone products used independently of SCADA, serving as enterprise-wide process data repositories. The historian stores raw data. The MES contextualises data. A historian can tell you "the temperature on machine 7 was 248 °C at 14:03:17." The MES can tell you "the temperature on machine 7 dropped below 250 °C during order #4712 on shift 2, and the reject rate for that order was 3.2 % compared to 0.8 % on orders where temperature stayed above 250 °C."
Related: MES: Definition & Functions · ISA-95 · OPC UA · OEE Explained · SYMESTIC Process Data · SYMESTIC Alarms Module · SYMESTIC Production Metrics
About the author
Mark Kobbert
CTO at SYMESTIC. Built the cloud-native MES platform from the ground up on Microsoft Azure. Has connected 15,000+ machines across 18 countries, from modern OPC UA-enabled lines to 30-year-old presses with nothing but a relay output. The architectural decision that matters most: whether data flows through a local SCADA server or directly to the cloud. Both work. One scales. · LinkedIn
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