QJ71C24-R2 Mitsubishi MELSEC-Q Series C24 Serial Communication Module PLC Interface Board

QJ71C24-R2 Module

MELSEC-Q Serial Communication

RS-232/422 PLC Module

QJ71C24-R2

The QJ71C24-R2 Module is a MELSEC-Q Series Serial Communication PLC Module supporting RS-232/422 interfaces for industrial automation data exchange and device connectivity.

Specification

SEODescription

The **QJ71C24-R2 Module** is a **MELSEC-Q Serial Communication** interface designed for seamless integration in industrial automation systems. This **RS-232/422 PLC Module** supports dual communication ports (1 RS-232 and 1 RS-422/485) for versatile connectivity with peripherals like sensors, HMIs, and other PLCs. It operates at 5VDC with a voltage tolerance of ±5% and functions reliably within 0–55°C, suitable for harsh industrial environments. The module directly interfaces with up to 64 MELSEC-Q series I/O modules via the PLC backplane, enabling scalable system expansion. Key advantages include high-speed data transfer (up to 115.2 kbps), protocol flexibility (MC protocol, non-procedural communication), and robust noise resistance. However, its configuration complexity and dependency on proprietary software may require specialized expertise. Widely used in manufacturing, energy, and process control, the QJ71C24-R2 excels in real-time data exchange and system integration.

SEOSpecification

Parameter	Specification
Model	QJ71C24-R2 Module
Series	MELSEC-Q Serial Communication Module
Interface Type	RS-232/422 (Switchable)
Baud Rate	300 to 115,200 bps
Data Bits	7 or 8 bits
Stop Bits	1 or 2 bits
Parity	None/Even/Odd
Protocol Support	Non-procedural/MC Protocol
PLC Compatibility	MELSEC-Q Series PLC
Power Consumption	5V DC 0.2A (Typical)
Operating Temp.	0 to 55°C
LED Indicators	RUN, ERR, SD, RD

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SEOQandA

question:Can the company ensure stable product supply?
answer:Yes, we maintain reliable inventory and efficient logistics for consistent supply.
question:What payment methods does the company accept?
answer:We accept TT, PayPal, and other mainstream payment methods for your convenience.
question:Does the company offer technical selection support?
answer:Yes, our experts assist in selecting optimal technical solutions tailored to your needs.

SEOQandA_Product

question:How to resolve communication failure between QJ71C24-R2 and external device?
answer:Verify baud rate, data format settings match both devices. Check cable connections and ensure correct wiring for RS-232/422/485.
question:Why does QJ71C24-R2 show error codes in buffer memory?
answer:Read error code from buffer memory (address 0 to 1FH), refer to manual for code definitions. Common fixes include correcting parameter settings or hardware reconfiguration.
question:How to troubleshoot unstable data transmission with QJ71C24-R2?
answer:Use shielded cables, reduce cable length, add terminating resistors for RS-422/485. Check for electrical noise sources and ensure proper grounding.
question:Why doesn't QJ71C24-R2 respond to MC protocol commands?
answer:Confirm protocol selection in GX Works2 parameters. Check station number settings and ensure correct command format with proper header/terminator.
question:How to fix incorrect wiring for RS-485 communication on QJ71C24-R2?
answer:Connect SDA-RDA and SDB-RDB pairs for full-duplex. Use twisted-pair cables, ensure proper termination (110Ω resistor) at both ends of the network.