Hello! now
tms@lcdchip.com
Mitsubishi Electric Industrial Automation Parts
Mitsubishi QJ71E71-100 Ethernet Module: Stock, Specifications, Replacement Options and Buying Guide
The Mitsubishi Electric QJ71E71-100 is an Ethernet communication module for the MELSEC-Q PLC platform. It is commonly used in factory automation systems where a Q Series PLC needs to communicate with HMI panels, SCADA systems, engineering workstations, or plant-level monitoring networks.
QJ71E71-100 at a Glance
Ethernet communication module for Mitsubishi MELSEC-Q PLC systems, supporting 10BASE-T / 100BASE-TX network connection through an RJ45 interface.
- Designed for Mitsubishi Q Series PLC systems
- Used for HMI, SCADA, PC, and factory Ethernet communication
- Commonly purchased for maintenance, repair, and spare stock
What Is the Mitsubishi QJ71E71-100?
The QJ71E71-100 is a Mitsubishi Electric Ethernet communication module designed for the MELSEC-Q Series PLC platform. It provides Ethernet connectivity through a standard RJ45 port and supports 10BASE-T / 100BASE-TX communication.
In real factory environments, this module is usually installed in a PLC rack to connect the control system with upper-level devices such as HMI panels, SCADA computers, engineering laptops, data collection servers, or industrial Ethernet switches.
Unlike low-cost electronic components, industrial automation modules are often purchased because a machine must keep running. For this reason, buyers usually care about stock availability, product condition, delivery time, compatibility, warranty, and replacement risk, not only the unit price.
QJ71E71-100 Key Specifications
Before ordering a Mitsubishi QJ71E71-100 module, check the core specifications against your existing PLC rack, CPU module, engineering software, and network configuration.
| Manufacturer | Mitsubishi Electric |
|---|---|
| Part Number | QJ71E71-100 |
| Product Type | Ethernet communication module / Ethernet interface module |
| PLC Platform | MELSEC-Q Series |
| Network Interface | Ethernet |
| Communication Standard | 10BASE-T / 100BASE-TX |
| Connector | RJ45 |
| Typical Application | PLC Ethernet communication, SCADA connection, HMI communication, data acquisition, factory network integration |
| Common Buying Purpose | Machine repair, spare stock, system expansion, and legacy PLC maintenance |
Note: Always verify the final specification from the Mitsubishi Electric manual and your machine documentation before installation. PLC module compatibility depends on the rack, CPU, network configuration, software version, and project settings.
Where Is QJ71E71-100 Used?
The QJ71E71-100 is not just a network accessory. In a MELSEC-Q automation system, it can become the bridge between the PLC control layer and the factory information layer.
QJ71E71-100 is commonly used to connect Mitsubishi MELSEC-Q PLC systems with HMI panels, SCADA software, engineering workstations, or factory Ethernet networks.
1. Connecting PLC to SCADA
Many production lines use SCADA software to monitor operating status, alarms, production counts, temperature data, motor operation, and downtime events. A QJ71E71-100 module allows the MELSEC-Q PLC system to communicate over Ethernet with a supervisory computer or industrial server.
2. HMI and Operator Panel Communication
In machine control panels, the Ethernet module may be used to exchange data between the PLC and an HMI panel. This is common in packaging machines, conveyors, inspection systems, textile machinery, food processing equipment, and automated assembly lines.
3. Remote Monitoring and Maintenance
Maintenance teams may need Ethernet access to check PLC status, read diagnostic information, back up programs, or monitor machine conditions. For older Q Series systems that still run reliably, replacing a damaged Ethernet module can be more practical than replacing the entire PLC platform.
4. Factory Data Collection
Manufacturers often want to collect production data from existing equipment without redesigning the full control system. With the right configuration, an Ethernet communication module can help send PLC data to a local database, MES gateway, or monitoring workstation.
Why Buyers Search for QJ71E71-100 Stock
Industrial automation parts are different from consumer electronics. A single failed PLC communication module can stop a machine, delay production, or interrupt a scheduled maintenance window. That is why buyers often search for terms like QJ71E71-100 stock, QJ71E71-100 price, Mitsubishi QJ71E71-100 supplier, or QJ71E71-100 replacement.
- Urgent machine repair: The original Ethernet module has failed or shows communication errors.
- Spare parts planning: Maintenance teams want to keep one or more modules in stock for older production lines.
- System expansion: A Q Series PLC system needs Ethernet communication for a new HMI, SCADA, or data acquisition project.
- Legacy automation support: The production line still uses MELSEC-Q hardware, and a full migration is not yet scheduled.
- Lead-time pressure: Buyers need a faster procurement option than waiting for standard factory lead time.
QJ71E71-100 vs QJ71E71-100C: What Should You Check?
Some buyers may see related part numbers such as QJ71E71-100 and QJ71E71-100C. In industrial automation procurement, a suffix may indicate a specific version, coating, regional supply, or distributor-side product description.
Before purchasing, do not rely only on the short part number. Ask the supplier to confirm:
- Exact manufacturer part number on the product label
- Whether the module is new, unused surplus, refurbished, or used
- Whether conformal coating is required for your environment
- Production date or lot information if available
- Packaging condition and label photos
- Warranty terms and return policy
For industrial repair projects, these details matter. A module that looks similar may not be acceptable if the production line requires a specific version, coating, or certification record.
Replacement and Lifecycle Notes: Is RJ71EN71 a Direct Replacement?
Some Mitsubishi product information may list RJ71EN71 as a lifecycle successor for QJ71E71-100. However, buyers should understand an important point: a lifecycle successor is not always a simple drop-in replacement.
The QJ71E71-100 belongs to the MELSEC-Q Series. Newer Ethernet modules may belong to a different Mitsubishi automation platform. Moving from a Q Series module to a newer series may require changes to the base unit, CPU, engineering software, network parameters, and PLC project configuration.
Important Procurement Advice
If your machine is already running on a Q Series PLC rack, replacing a failed QJ71E71-100 with the same part number is usually the lowest-risk maintenance path. If you are planning a new build or a full automation upgrade, then a newer platform and successor module may be worth evaluating.
| Option | Best For | Risk Level |
|---|---|---|
| Buy QJ71E71-100 | Repairing or maintaining an existing MELSEC-Q system | Lower, if the original machine already uses this module |
| Evaluate RJ71EN71 | Platform migration or new automation system design | Medium to high, because migration work may be required |
| Use a third-party communication gateway | Special integration projects or data collection add-ons | Depends on protocol, software, and site requirements |
How to Verify Compatibility Before Ordering
A good distributor should not only quote a price. For industrial automation parts, the supplier should help the buyer reduce replacement risk. Before placing an order for QJ71E71-100, prepare the following information:
- Existing module photo: Front label, side label, terminal area, and rack position.
- PLC rack information: Base unit model, CPU model, power supply model, and current module layout.
- Project requirement: Replacement, spare stock, new installation, or system expansion.
- Network configuration: IP address, subnet, communication protocol, connected HMI or SCADA software.
- Required condition: New original, new surplus, refurbished, tested used, or urgent replacement unit.
- Delivery destination: Country, required delivery time, and shipping method.
Sending this information with your RFQ can save time and reduce back-and-forth communication. It also helps the supplier check whether QJ71E71-100 is the right module or whether a related Mitsubishi Ethernet module should be considered.
Common Symptoms of a Failing Ethernet Communication Module
A production line may not always show a clear "module failed" message. Ethernet communication issues can look like software, cable, network, or PLC problems. Before replacing the module, maintenance engineers usually check several points.
Possible Symptoms
- SCADA or HMI cannot communicate with the PLC
- Network timeout or unstable communication
- Ethernet diagnostic error
- Link indicator does not behave normally
- PLC data cannot be read by the monitoring computer
- Communication works intermittently after power cycling
Before Replacing the Module
- Check Ethernet cable and RJ45 connector
- Confirm IP address and network settings
- Inspect switch port and factory network configuration
- Review PLC diagnostics and error code history
- Check power supply and base unit condition
- Back up the PLC project before major maintenance
Simple Ethernet Communication Topology
This simplified layout shows how QJ71E71-100 can act as the Ethernet bridge between a Mitsubishi Q Series PLC rack and upper-level monitoring or control systems.
Buying Checklist for QJ71E71-100
When buying industrial automation spare parts online, the cheapest quotation is not always the safest option. For discontinued, long-lead-time, or hard-to-find PLC modules, the main risk is not only price. It is also authenticity, condition, lead time, and whether the part will actually work in your cabinet.
| Item to Check | Why It Matters |
|---|---|
| Exact part number | Prevents confusion between similar Mitsubishi Q Series communication modules. |
| Product condition | New original, surplus, refurbished, and used modules have different risk levels. |
| Label and packaging photos | Helps verify the product before payment and shipment. |
| Testing record | Useful when buying surplus or refurbished industrial automation parts. |
| Warranty period | Important for repair projects and plant maintenance purchasing. |
| Shipping time | Critical when a stopped machine is waiting for replacement parts. |
| Return policy | Protects the buyer if the wrong model or incompatible part is supplied. |
QJ71E71-100 Stock and RFQ
LCDChip supplies Mitsubishi Electric industrial automation components, including PLC modules, HMI parts, communication modules, servo-related components, and other factory maintenance spare parts.
If you are sourcing QJ71E71-100, send us your required quantity, destination country, and expected delivery time. Our team can help check current stock, price, product condition, and shipping options.
Request QJ71E71-100 Price and Stock
Need urgent Mitsubishi Electric PLC spare parts? Send your RFQ and we will respond with availability, quotation, and delivery details.
View QJ71E71-100 Product Page Send RFQRelated Mitsubishi Electric Parts Buyers Often Search
If you maintain Mitsubishi Electric automation systems, you may also need related PLC, HMI, CPU, communication, servo, or inverter spare parts. For a faster quotation, send the full part number and machine information together.
FAQ: Mitsubishi QJ71E71-100
What is QJ71E71-100 used for?
QJ71E71-100 is used to add Ethernet communication capability to Mitsubishi MELSEC-Q Series PLC systems. It is commonly used for HMI communication, SCADA connection, remote monitoring, PLC programming access, and factory data collection.
Is QJ71E71-100 an Ethernet module?
Yes. QJ71E71-100 is an Ethernet communication module with an RJ45 interface for 10BASE-T and 100BASE-TX network connection.
Can RJ71EN71 replace QJ71E71-100?
RJ71EN71 may be listed as a lifecycle successor in some Mitsubishi Electric product information, but it should not be treated as a simple drop-in replacement without checking the PLC platform, base unit, CPU, software, and project migration requirements.
What should I check before buying QJ71E71-100?
Check the exact part number, product condition, label photos, compatibility with your Q Series PLC system, warranty, delivery time, and return policy. If the module is for urgent repair, also confirm whether the supplier can ship immediately.
Where can I buy QJ71E71-100?
You can request QJ71E71-100 from LCDChip. Send your required quantity, delivery country, and whether you need new original, surplus, or tested replacement stock.
