{"product_id":"mitsubishi-electric-qj71mt91-melsec-q-series-modbus-tcp-network-module","title":"Mitsubishi Electric QJ71MT91 MELSEC Q Series Modbus\/TCP Network Module","description":"\u003ch3\u003eDescription\u003c\/h3\u003e\n\u003cp style=\"color: #2d3748; margin-bottom: 1rem;\"\u003eDesigned for seamless integration within MELSEC Q Series control architectures, the \u003cstrong\u003eMitsubishi Electric QJ71MT91\u003c\/strong\u003e 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.\u003c\/p\u003e\n\n\u003ch3\u003eKey Features\u003c\/h3\u003e\n\u003cul style=\"list-style-type: square; color: #2d3748; margin-bottom: 1.5rem; padding-left: 1.5rem;\"\u003e\n  \u003cli\u003eDual functionality supports concurrent Master and Slave execution roles over the network.\u003c\/li\u003e\n  \u003cli\u003eBuilt-in automatic communication utility simplifies data exchange without complex sequence ladder programming.\u003c\/li\u003e\n  \u003cli\u003eHigh-density buffer memory provides robust storage capacity for 4k words of input and output data.\u003c\/li\u003e\n  \u003cli\u003eStandard RJ45 physical layer interface supports industrial Ethernet architectures.\u003c\/li\u003e\n  \u003cli\u003eDirect integration onto the MELSEC Q series baseplate, drawing power directly from the backplane system.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eApplications\u003c\/h3\u003e\n\u003cul style=\"list-style-type: square; color: #2d3748; margin-bottom: 1.5rem; padding-left: 1.5rem;\"\u003e\n  \u003cli\u003eIntegration of multi-vendor PLC platforms (e.g., interfacing Modicon or Beckhoff controllers with MELSEC systems).\u003c\/li\u003e\n  \u003cli\u003eDistributed SCADA and HMI network interfaces over enterprise-wide local area networks.\u003c\/li\u003e\n  \u003cli\u003eReal-time telemetry and control of field instruments, power meters, and variable frequency drives over Modbus\/TCP.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cdiv style=\"overflow-x: auto; width: 100%; margin-bottom: 1.5rem;\"\u003e\n  \u003ctable style=\"border-collapse: collapse; width: 100%; color: #2d3748; border: 1px solid #e2e8f0;\"\u003e\n    \u003cthead\u003e\n      \u003ctr style=\"border-bottom: 2px solid #cbd5e0;\"\u003e\n        \u003cth style=\"padding: 10px; text-align: left; font-weight: bold;\"\u003eParameter\u003c\/th\u003e\n        \u003cth style=\"padding: 10px; text-align: left; font-weight: bold;\"\u003eValue \/ Specification\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eManufacturer\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eMitsubishi Electric\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eModel Reference\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eQJ71MT91\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eProduct Type\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eModbus\/TCP Interface Module\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003ePhysical Interface\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eRJ45 Connector\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eMaximum Connection Count\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e64 logical connections\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eMax Slaves Supported\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e64 slaves\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eBuffer Memory Allocation (I\/O)\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e4k words Input \/ 4k words Output\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eMax Concurrent Instructions\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eUp to 8 active instructions\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eMax Payload size (per instruction)\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e253 bytes\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eI\/O Points Occupied\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e32 points (on baseplate)\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eInternal Current Draw (5VDC)\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e0.52A\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eModule Weight\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e0.11 kg\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eShipping Weight (Calculated)\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e1.50 kg\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eStandards \u0026amp; Approvals\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eUL, cUL, CE\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch3\u003eEmpirical Engineering Insights\u003c\/h3\u003e\n\n\u003ch4\u003eAlternative Models \u0026amp; Compatibility\u003c\/h4\u003e\n\u003cp style=\"color: #2d3748; margin-bottom: 1rem;\"\u003eThe 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.\u003c\/p\u003e\n\n\u003ch4\u003eApplication Pitfalls \u0026amp; Engineering Notes\u003c\/h4\u003e\n\u003cp style=\"color: #2d3748; margin-bottom: 1rem;\"\u003eEngineering 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.\u003c\/p\u003e\n\n\u003ch4\u003eCommissioning \u0026amp; Wiring Tips\u003c\/h4\u003e\n\u003cp style=\"color: #2d3748; margin-bottom: 1rem;\"\u003eTo 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.\u003c\/p\u003e\n\n\u003ch3\u003eInstallation Guidelines\u003c\/h3\u003e\n\u003cdiv style=\"background-color: #fff5f5; border-left: 4px solid #c53030; padding: 1rem; margin-bottom: 1.5rem; border-radius: 4px;\"\u003e\n  \u003cstrong style=\"color: #9b2c2c; display: block; margin-bottom: 0.5rem;\"\u003eCRITICAL WARNING\u003c\/strong\u003e\n  \u003cp style=\"color: #9b2c2c; margin: 0; font-size: 0.95rem;\"\u003eAlways 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.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cdiv style=\"display: flex; flex-direction: column; gap: 1rem; margin-bottom: 1.5rem;\"\u003e\n  \u003cdiv style=\"display: flex; align-items: flex-start; gap: 1rem;\"\u003e\n    \u003cdiv style=\"background-color: #2b6cb0; color: #ffffff; width: 28px; height: 28px; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: bold; flex-shrink: 0;\"\u003e1\u003c\/div\u003e\n    \u003cp style=\"color: #2d3748; margin: 0; padding-top: 3px;\"\u003eEnsure 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.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv style=\"display: flex; align-items: flex-start; gap: 1rem;\"\u003e\n    \u003cdiv style=\"background-color: #2b6cb0; color: #ffffff; width: 28px; height: 28px; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: bold; flex-shrink: 0;\"\u003e2\u003c\/div\u003e\n    \u003cp style=\"color: #2d3748; margin: 0; padding-top: 3px;\"\u003ePush 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.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv style=\"display: flex; align-items: flex-start; gap: 1rem;\"\u003e\n    \u003cdiv style=\"background-color: #2b6cb0; color: #ffffff; width: 28px; height: 28px; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: bold; flex-shrink: 0;\"\u003e3\u003c\/div\u003e\n    \u003cp style=\"color: #2d3748; margin: 0; padding-top: 3px;\"\u003eInsert 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.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e","brand":"Mitsubishi Electric","offers":[{"title":"Default Title","offer_id":53102144815467,"sku":"QJ71MT91","price":100.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0953\/3227\/0443\/files\/qj71mt91-tw1fpcynekd.png?v=1776138010","url":"https:\/\/www.plcprotech.com\/de\/products\/mitsubishi-electric-qj71mt91-melsec-q-series-modbus-tcp-network-module","provider":"PLC ProTech Ltd.","version":"1.0","type":"link"}