QJ71LP21G CC-Link Network Module - Mitsubishi Electric MELSEC-Q Series PLC Interface Board

QJ71LP21G Module

Mitsubishi CC-Link/LT

MELSEC Network Interface

QJ71LP21G

The QJ71LP21G Module by Mitsubishi is a CC-Link/LT interface designed for MELSEC network systems, enabling reliable data communication and seamless integration with automation devices.

Specification

SEODescription

The **QJ71LP21G Module** is a **Mitsubishi CC-Link/LT**-compatible **MELSEC Network Interface** unit designed for industrial automation systems. It supports up to **64 remote I/O points** and can directly connect up to **64 modules** via its **RS-485-based CC-Link/LT network**, enabling distributed control with simplified wiring. Operating at **5VDC** with a temperature range of **0–55°C**, it is ideal for manufacturing, assembly lines, and machinery control. The module features **high noise immunity** and **low-cost installation** due to flat-cable communication. However, its **maximum communication distance is limited to 500 meters**, and it lacks advanced protocols like Ethernet. The QJ71LP21G excels in small-to-medium-scale systems requiring reliable, cost-effective sensor/actuator integration.

SEOSpecification

Parameter	Specification
Module Model	QJ71LP21G
Network Type	Mitsubishi CC-Link/LT
Protocol	CC-Link/LT Ver.1.0 compliant
Transmission Speed	156 kbps / 625 kbps
Maximum Nodes	64 stations per network
Communication Distance	500m max (156kbps, Thick cable)
Power Supply	5VDC ±5% (Internal bus power)
Operating Temperature	0°C to 55°C
Mounting	MELSEC-Q series base unit
Compatibility	MELSEC-QnA/Q series PLCs
Interface	MELSEC Network Interface (CC-Link/LT master)
Diagnostics	LED indicators for RUN, ERR, SD/RD
IP Rating	IP2X (front protection)
Weight	0.2 kg
Certification	CE, UL, RoHS compliant

SEOQandA

question:What happens if a refurbished product malfunctions during use?
answer:We offer a replacement or refund immediately upon verification of the issue.
question:Do you provide technical selection services?
answer:Yes, our experts assist in choosing the best solutions tailored to your needs.
question:Can your company ensure stable product supply?
answer:Our robust supply chain guarantees consistent and timely product availability.

SEOQandA_Product

question:QJ71LP21G communication failure with HART devices
answer:Check HART signal configuration and ensure proper cable shielding. Verify device addressing in parameter settings.
question:QJ71LP21G not detected in PLC system
answer:Confirm module installation in correct slot. Verify DIP switch settings and power supply connections.
question:Inconsistent HART data on QJ71LP21G
answer:Ensure HART devices use 4-20mA mode. Use shielded twisted-pair cables and minimize electrical interference.
question:QJ71LP21G module status LED is off
answer:Check power supply voltage (24VDC ±10%). Verify backplane connector and wiring integrity.
question:HART command timeout errors with QJ71LP21G
answer:Adjust communication timeout settings in GX Works2. Validate device compatibility and signal loop integrity.