LJ71GF11-T2-CM Mitsubishi CC-Link IE Field Master Local Module MELSEC-L

Product Overview

The Mitsubishi LJ71GF11-T2-CM (LJ71GF11T2CM) is a high-capacity CC-Link IE Field Network master/local station module designed specifically for the MELSEC-L Series PLC. Operating at a blistering 1 Gbps communication speed, this module integrates field devices, remote I/O, and other controllers into a seamless, high-speed Ethernet-based network. Optimized for data-intensive industries such as liquid crystal display (LCD) manufacturing, high-speed packaging, and complex food processing, the LJ71GF11-T2-CM provides the massive bandwidth required for real-time motion control and large-scale diagnostic data collection. By utilizing standard Category 5e (or higher) double-shielded cables, it offers a cost-effective yet industrial-grade solution for reducing network latency and maximizing total system throughput.

Technical Configuration

The LJ71GF11-T2-CM is a versatile communication hub that can be configured either as a "Master Station" to manage a network or as a "Local Station" to exchange data with other masters. It supports a staggering 16,384 points of remote I/O and 8,192 words of remote registers, allowing it to handle extremely complex field configurations without performance degradation.

The module features a 1 Gbps transmission rate using standard Ethernet physical layers (1000BASE-T). It supports flexible network topologies including line, star, and ring configurations. In a ring topology, the module provides enhanced reliability through a loop-back function, ensuring the network remains operational even if a single cable is disconnected. Note that this module requires a MELSEC-L CPU with a serial number prefix of "13012" or later to utilize its full high-speed functional range.

Technical Specifications

Technical FAQs

Q1: What is the significance of the "CM" suffix in this model number?

A1: The "CM" suffix typically denotes the "Chinese Market" or specific regional compliance version, which may include localized documentation or specific environmental certifications while maintaining identical technical performance to the standard LJ71GF11-T2.

Q2: How do I implement a Ring Topology with this module?

A2: To utilize a ring topology, connect the cables in a continuous loop and configure the "Network Topology" setting to "Ring" within the GX Works2 parameter settings. This enables the loop-back function for redundant communication paths.

Q3: Why is my module not recognized by the L-Series CPU?

A3: Ensure your CPU's serial number starts with "13012" or later. Older CPU revisions do not have the internal bus logic required to communicate with the high-speed CC-Link IE Field hardware.

Engineering & Installation Guide

• Cable Selection: Only use Category 5e or higher STP (Shielded Twisted Pair) cables that are specifically rated for 1000BASE-T. For industrial environments with high EMI (Electromagnetic Interference), double-shielded cables are highly recommended to prevent packet loss at 1 Gbps speeds.

• Redundancy Planning: If using a star topology, the network requires an industrial-grade switching hub that supports 1 Gbps. For mission-critical applications, the ring topology is preferred as it eliminates the switching hub as a single point of failure.

• Heat Dissipation: The LJ71GF11-T2-CM consumes 0.89 A of internal current, which is relatively high for an L-Series module. Ensure that the total current consumption of all modules on the branch does not exceed the power supply unit's (PSU) capacity, and maintain proper ventilation gaps in the control cabinet.