Manufacturer: Mitsubishi Electric
Product No.: QJ71MT91
Country of origin:United States
Product Type: Modbus/TCP Network Modules
Payment: T/T, Western Union
Weight: 110g
Shipping port: Xiamen
Warranty: 12 months
Designed for seamless integration within MELSEC Q Series control architectures, the Mitsubishi Electric QJ71MT91 establishes reliable Ethernet-based communications by acting as a dedicated interface between high-performance PLCs and Modbus/TCP networks. This module allows MELSEC system processors to exchange data efficiently with third-party devices, instruments, and supervisory SCADA platforms over standard TCP/IP frameworks. Operating seamlessly in both master and slave capacities, it eliminates the need for expensive protocol converters or custom communication scripts in multi-vendor environments.
| Parameter | Value / Specification |
|---|---|
| Manufacturer | Mitsubishi Electric |
| Model Reference | QJ71MT91 |
| Product Type | Modbus/TCP Interface Module |
| Physical Interface | RJ45 Connector |
| Maximum Connection Count | 64 logical connections |
| Max Slaves Supported | 64 slaves |
| Buffer Memory Allocation (I/O) | 4k words Input / 4k words Output |
| Max Concurrent Instructions | Up to 8 active instructions |
| Max Payload size (per instruction) | 253 bytes |
| I/O Points Occupied | 32 points (on baseplate) |
| Internal Current Draw (5VDC) | 0.52A |
| Module Weight | 0.11 kg |
| Shipping Weight (Calculated) | 1.50 kg |
| Standards & Approvals | UL, cUL, CE |
The QJ71MT91 is a dedicated Modbus/TCP module that provides native TCP/IP encapsulation for Modbus protocols. When migrating older systems from serial Modbus (RTU/ASCII) architectures previously managed by the QJ71C24N module, the QJ71MT91 offers a modern Ethernet upgrade without necessitating significant redesign of the backplane. This module requires GX Works2 or GX Developer utility software for module parameter setup and configuration profile mapping.
Engineering systems incorporating multiple network-heavy modules must carefully calculate backplane current consumption. The QJ71MT91 draws a substantial 0.52A from the 5VDC internal bus line. Always verify that your power supply module (e.g., Q61P, Q63P) can supply sufficient current to avoid unexplained system resets or communications interruptions during heavy packet routing phases.
To guarantee clean execution and isolate industrial data lines from electromagnetic noise, ensure all Ethernet cabling running from the RJ45 port of the module is category 5e/6 STP (Shielded Twisted Pair). Ensure the shield of the physical Ethernet line is correctly bonded to the control panel's ground point. If accessing the module through firewalls, keep standard Modbus/TCP port 502 open for bidirectional protocol traffic.
Always isolate all phase power supplies feeding the rack and the field cabling interfaces prior to installing, removing, or wiring any network communications modules. Failure to fully de-energize active industrial panels before physical servicing can damage delicate backplane circuit components or result in immediate diagnostic hardware faults.
Ensure the base rack and adjacent CPU are powered down entirely. Carefully align the lower projection hook of the module with the bottom guide slot on the Q Series baseplate.
Push the module forward firmly into the backplane connector until it sits flush against the adjacent modules, securing it with the top module fixing screw if required in high-vibration environments.
Insert the shielded RJ45 connector into the front interface port until the locking tab clicks securely, ensuring the physical drop line does not exceed maximum local node spacing limits.
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Returns & Warranty
Global Express Shipping
Returns & Warranty
Orders are processed and delivered Monday-Friday (excluding public holidays).
For full eligibility, restocking fees, and international return details, please view our official Refund & Return Policy .
| Country of origin |
United States
|
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