Mitsubishi Electric Q26UDEHCPU MELSEC Q Series Universal CPU Module

Description

Engineered for high-density, multi-disciplinary industrial control applications, the Mitsubishi Electric Q26UDEHCPU is an industrial-grade central processing unit designed for the MELSEC Q Series automation platform. This module integrates a built-in Ethernet port, enabling high-speed data transmission and seamless communication across factory networks. Featuring a highly optimized execution engine, it handles complex arithmetic, sequence controls, and structured text configurations with exceptional speed. Its physical design fits directly onto standard Q Series base units, making it ideal for systems requiring intensive calculations, multi-CPU coordination, and deep memory capacities.

Key Features

• High-Speed Processing: Delivers execution speeds of 9.5 ns for basic sequence instructions (LD X0) and 19 ns for data movement operations (MOV D0 D1).
• Large Memory Footprint: Provides 260 K steps (1040 KB) of program memory, supplemented by 1280 KB of standard RAM and 4096 KB of standard ROM.
• Built-In Communication: Integrated 100/10 Mbps Ethernet port supporting up to 16 simultaneous socket, MELSOFT, or MC protocol connections, plus 1 dedicated FTP channel.
• Scalable I/O Capacity: Supports up to 4096 local physical I/O points and an extended logical device range of up to 8192 points.
• Flexible Programming: Native support for Relay symbol words, Logic symbols, MELSAP 3 (SFC), MELSAP-L, Function Blocks, and Structured Text (ST).

Applications

• High-speed automated packaging and assembly systems.
• Multi-axis synchronization systems involving complex motion control integration.
• Water and wastewater plant control network hubs.
• High-volume data logging, tracking, and MES upstream communication networks.

Technical Specifications

Connections and Interfaces

Empirical Engineering Insights

Alternative Models & Compatibility

When migrating to the Q26UDEHCPU from legacy non-universal hardware such as the Q25HCPU, engineering configurations must be updated in GX Works2. Universal models use a distinct memory organization structure (Standard RAM Drive 3 is handled differently). Additionally, confirm that any installed extension base units support the high-speed bus interfaces associated with Universal CPUs to prevent bus latency errors.

Application Pitfalls & Engineering Notes

This CPU draws 0.49 A from the 5 VDC internal power rail. When configuring multiple CPUs or high-density network modules on a single rack (e.g., combining this CPU with multiple Ethernet/CC-Link IE units), perform a rigorous current consumption calculation. Standard power supplies like the Q61P may approach their operational limit, requiring an upgrade to high-capacity options such as the Q63P or Q64PN.

Commissioning & Wiring Tips

To maintain maximum throughput on the built-in Ethernet port, avoid routing communication patch cords parallel to motor lines or high-voltage lines. Always use Category 5e Shielded Twisted Pair (STP) cabling. If the Ethernet connection drops or times out under heavy factory floor noise, check that the ground terminal (LG/FG) on the main power supply module is securely tied to a dedicated Class D ground.

Installation Guidelines