The Mitsubishi QJ71MB91 is a high-performance communication interface module designed for the MELSEC-Q Series PLC, enabling seamless integration with Modbus (RTU/ASCII) networks. This module allows Mitsubishi PLCs to act as Modbus master or slave devices, facilitating data exchange with sensors, drives, and other Modbus-compatible equipment in industrial automation systems.
Key Specifications
Communication Protocol: Modbus RTU/ASCII (supports master/slave modes)
Interface: RS-485 (2-wire/4-wire)
Baud Rate: 300 to 115,200 bps (configurable)
Data Format: Adjustable (parity, stop bits, data length)
Max. Stations: 32 devices (RS-485 network)
Isolation: Photocoupler isolation for noise immunity
Mounting: Direct installation on Q Series base unit
Operating Temperature: 0°C to 55°C
Power Consumption: 5V DC, 0.35A (from PLC backplane)
Main Features
✔ Dual-Mode Operation – Functions as Modbus master (polling) or slave (responding)
✔ Easy Configuration – Set parameters via GX Works2/3 software
✔ High-Speed Data Exchange – Optimized for real-time industrial communication
✔ Diagnostic LEDs – Visual indicators for RUN, ERR, SD, RD status
✔ Compatibility – Works with Q00/Q01/Q02/Q06/Q12/Q13/Q26 CPUs
✔ Flexible Wiring – Supports terminal block or RJ45 connector (with adapter)
Typical Applications
Integration with Modbus RTU devices (sensors, meters, inverters)