HMI With Built-In PLC – The All-in-One Approach
A traditional Human-Machine Interface (HMI) paired with a separate Programmable Logic Controller (PLC) requires two devices, extra wiring, and more cabinet space. An HMI with built-in PLC integrates both functions into a single unit, streamlining machine control, reducing hardware costs, and simplifying programming. This concept is increasingly implemented using powerful industrial PCs that run software-based PLC runtimes (e.g., CODESYS, TwinCAT, or IEC 61131-3 environments) alongside a modern HMI application – offering the same capability as dedicated hardware but with greater flexibility and upgradeability.
Key Specifications for HMI + PLC Integration
For a mini PC to effectively serve as both HMI and PLC, it must meet certain performance and connectivity requirements:
| Specification | Recommended Level | Why It Matters |
|---|---|---|
| Processor | Intel® N100 or higher (4 cores, 6W TDP) | Handles HMI graphics and real-time PLC logic simultaneously |
| RAM | 8 – 16 GB DDR4 | Smooth multitasking, especially with complex visualizations |
| Storage | 128 GB SSD or larger | Fast boot, reliable data logging, and application storage |
| Operating System | Windows 11 IoT / Ubuntu Linux | Compatible with leading HMI/PLC software packages |
| Connectivity | Dual Ethernet, USB 3.2, optional COM ports | Fieldbus integration (Modbus TCP, PROFINET, EtherNet/IP) |
| Cooling | Fanless design | Dust-free operation, zero vibration, extended lifespan in industrial settings |
Applications in Industrial Automation
A single device with HMI and PLC capabilities is ideal for:
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Compact machines where space is at a premium (packaging, labeling, small assembly lines)
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Remote monitoring scenarios where a traditional PLC rack is not feasible
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Educational/training stations needing a low-cost
