Mitsubishi QJ71LP21-25 is a MELSEC-Q series MELSECNET/H network module used in PLC communication systems, factory automation networks, production line control, and industrial network replacement projects. It is designed for Q series PLC systems that require high-speed network communication between controllers, remote I/O stations, and automation equipment.
This model is important for plants that continue to operate MELSECNET/H-based automation systems. In older production lines, a network module failure can stop PLC-to-PLC communication, remote station control, or production data exchange. QJ71LP21-25 is therefore a valuable spare part for maintenance replacement and legacy PLC network support.
| Model | QJ71LP21-25 |
| Brand | Mitsubishi |
| Series | MELSEC-Q |
| Product Type | MELSECNET/H Network Module |
| Network Type | MELSECNET/H, confirm by installed system |
| Function | PLC Network Communication and Remote Station Connection |
| Application | Industrial PLC Network Integration |
| Replacement Check | Confirm network type, station setting, cable type, parameter setting, and PLC project |
QJ71LP21-25 is used in MELSEC-Q PLC systems with Q series CPU modules, base units, power supply modules, remote I/O systems, communication networks, and production line control architectures. It is suitable for large machines, multi-station production lines, material handling systems, process control networks, and factory automation systems using MELSECNET/H communication.
When replacing QJ71LP21-25, confirm the complete model number, network type, station number, cable connection, network parameter, PLC program, remote station layout, and existing communication structure. Network faults may also be caused by cable damage, station setting errors, parameter mismatch, remote module failure, or power supply problems.
Related models include QJ71LP21-25, QJ71LP21G, QJ71BR11, QJ72LP25-25, QJ72BR15, QJ71E71-100, and QJ71C24N. These models may differ by network type, cable system, remote station function, communication speed, and PLC system architecture.
DF Automatic supplies Mitsubishi MELSEC-Q network modules, Ethernet modules, serial communication modules, CPU modules, I/O modules, power supplies, base units, HMI panels, servo systems, inverter drives, and industrial automation spare parts for factory maintenance and legacy PLC network repair.
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