QJ71MT91 MODBUS/TCP Communication Module for MELSEC-Q | Mitsubishi

The Original New Mitsubishi QJ71MT91 is a MODBUS/TCP network communication module for the MELSEC-Q series, designed to integrate Q series programmable controllers into MODBUS/TCP networks. It operates simultaneously as both a MODBUS/TCP master and slave, enabling the PLC to control up to 64 MODBUS/TCP slave devices while also responding to requests from external MODBUS/TCP masters such as SCADA systems and HMIs. The module features a 10BASE-T/100BASE-TX Ethernet interface with an RJ45 connector, supports up to 64 simultaneous TCP connections, and includes KeepAlive and router relay functions for reliable network communication. Configuration is performed through GX Works2 or GX Developer with the GX Configurator-MB utility, allowing automatic communication settings or program-controlled communication as required.

Core Engineering Highlights:
MODBUS/TCP master and slave functions (simultaneous operation) | 10BASE-T/100BASE-TX (10/100 Mbps) | RJ45 connector | Up to 64 TCP connections | Max. 64 slaves | 4k words input / 4k words output area | MODBUS device size: 64k points (coil, input, holding register) | 32 occupied I/O points | 0.52 A internal current consumption (5 V DC) | 27.4 × 98 × 90 mm | 0.11 kg

Key Features:

• Original New Mitsubishi QJ71MT91 module

• Operates as both MODBUS/TCP master and slave simultaneously

• Master function: controls up to 64 MODBUS/TCP slave devices

• Slave function: responds to requests from external MODBUS/TCP masters (automatic response)

• Automatic communication function for simple data exchange without programming

• Dedicated instructions for program-controlled communication (MBRW, MBREQ)

• Up to 8 dedicated instructions can be executed concurrently

• Input area size: 4k words; Output area size: 4k words

• MODBUS device sizes: coil 64k points, input 64k points, holding register 64k points, extended file register up to 4086k points

• 10BASE-T/100BASE-TX Ethernet with RJ45 connector

• KeepAlive function for connection monitoring

• Router relay function for communication across network segments

• Up to 8 simultaneous GX Developer connections

• Configuration via GX Works2 or GX Developer with GX Configurator-MB

• Compact 27.4 mm width for high-density rack mounting

• RoHS compliant, CE, UL/cUL approved

Applications:

• Connecting MELSEC-Q series PLCs to MODBUS/TCP networks

• SCADA and HMI integration for process monitoring and control

• Multi-vendor device integration in factory automation

• Remote monitoring and data acquisition from MODBUS/TCP devices

• Distributed control systems in manufacturing and utilities

• Building automation and energy management systems

Technical Specifications:

System Compatibility:

• Compatible with Mitsubishi MELSEC-Q series PLCs, including Q00JCPU, Q00UCPU, Q01UCPU, Q02UCPU, Q03UDCPU, Q04UDHCPU, Q06HCPU, Q12HCPU, Q25HCPU, Q13UDHCPU, Q26UDHCPU, and other Q series CPU modules

• Installs in any MELSEC-Q series main base unit or extension base unit slot via the Q series backplane bus

• Configuration via GX Works2 (no additional purchase required) or GX Developer with GX Configurator-MB utility package

• Supports both automatic communication and program-controlled communication modes

Related Products:

• QJ71E71-100 – Ethernet communication module (10/100 Mbps) for MELSEC-Q series

• QJ71PB92V – PROFIBUS-DP master module for MELSEC-Q series

• QJ71C24N-R2 – Serial communication module (RS-232) for MELSEC-Q series

• Q61P – Power supply module for MELSEC-Q base units

• Q38B – 8-slot main base unit for Q series

• RJ71MT91 – MODBUS/TCP module for MELSEC iQ-R series (successor platform)

• GX Works2 – Engineering software for MELSEC-Q series

PLC ERA is an independent industrial automation distributor supplying genuine Original New products through established global supply channels. All products are factory sealed when applicable and undergo quality inspection prior to shipment. Mitsubishi, MELSEC, and MELSEC-Q are trademarks of Mitsubishi Electric Corporation.