Description
Designed for seamless industrial network integration, this communication interface connects MELSEC Q Series programmable controllers directly to EtherNet/IP networks. The Mitsubishi Electric QJ71EIP71 enables robust cyclic tag-based data exchanges, allowing high-speed PLC-to-PLC communication across complex manufacturing systems. Note that this specific module is engineered strictly for tag-based communication between programmable controllers and does not support standard assembly instance communication profiles.
Features
- Dedicated EtherNet/IP tag communication interface optimized for peer-to-peer CPU exchanges.
- Direct backplane integration with the MELSEC Q Series base units.
- Built-in diagnostic LEDs for real-time monitoring of network status, errors, and link activity.
- Reliable hardware design suited for high-noise, continuous-duty industrial environments.
Applications
- Inter-PLC data synchronization across automated manufacturing cells.
- Bridging Mitsubishi Electric control environments with wider plant-level EtherNet/IP networks.
- Process monitoring and distributed control architectures requiring deterministic cyclic messaging.
Technical Specifications
| Parameter |
Value |
| Manufacturer |
Mitsubishi Electric |
| Model Number |
QJ71EIP71 |
| Product Type |
EtherNet/IP Interface Module |
| Base Series |
MELSEC Q Series |
| Interface Port |
1x RJ45 Port |
| Transmission Speed |
100 Mbps / 10 Mbps (Auto-negotiation) |
| Communication Protocol |
EtherNet/IP (Tag Communication only; Instance-based communication not supported) |
| Internal Current Consumption |
0.45 A at 5V DC (supplied from rack backplane) |
| Country of Origin |
Japan |
| Shipping Weight (Calculated) |
2.0 kg |
Empirical Engineering Insights
Alternative Models & Compatibility
If your application requires communication with external sensor manifolds, remote I/O blocks, or third-party drives that only support Instance-based messaging (Class 1 Assembly instances), you cannot use the QJ71EIP71. Consider implementing a CC-Link IE Field Network module or using a dedicated third-party EtherNet/IP gateway module designed for slave-device instance integration.
Application Pitfalls & Engineering Notes
The QJ71EIP71 is strictly optimized for controller-to-controller data synchronization via Tag Communication. Always verify the memory capacity of the hosting Q-Series CPU, as extensive tag configurations can consume notable processing cycles and network buffer allocations during synchronous high-frequency polling.
Commissioning & Wiring Tips
Always use Category 5e (or higher) Shielded Twisted Pair (STP) cabling in plant floor environments. High-voltage transient noise from nearby variable frequency drives can degrade packet delivery. Ensure the ground terminal (FG) on the main Q Series base unit is securely connected to a low-impedance earth ground to maintain noise immunity through the RJ45 shield connection.
Installation Guidelines
CRITICAL WARNING: Completely de-energize the PLC base unit and all associated field power connections before inserting or removing the communication module. Failure to isolate the power supply can cause irreversible damage to the module internal circuitry, CPU backplane, and risk physical injury from unexpected system operations.
1
Ensure the MELSEC Q Series rack power is completely switched off and locked out.
2
Align the lower hook of the QJ71EIP71 module with the mounting hole of the base unit slot.
3
Push the module firmly into the base unit connector until it seats flush, then tighten the top mounting screw to the specified torque rating (0.36 to 0.48 N-m).
4
Connect the industrial STP Ethernet cable into the RJ45 port until the lock tab clicks securely into place.