OVERVIEW

Official designation: Omron CJ1W-ETN21 (CJ1W, Ethernet Unit)

Role/Application: Ethernet communications module integrating CJ-Series PLCs into an information network using FINS/TCP, FINS/UDP, FTP, and standard UDP/TCP protocols.

KEY SPECS SUMMARY

Power: 370 mA max. at 5 VDC

Interfaces / Ports: One RJ45 8-pin connector

Indicators: RUN, ERR/ALM, SD, RD, 100M, LINK LEDs

Operating Temp: 0 degrees C to 55 degrees C

Platform / Compatibility: Omron CJ-series, CPU Bus Unit

Limit: 100 Mbit/s, 100 m distance, 254 FINS nodes

Lifecycle: Discontinued

FREQUENTLY ASKED QUESTIONS

Technical Specifications:

Q: What are the supported Ethernet protocols and media access method for the unit?

A: Protocols include FINS/TCP, FINS/UDP, and EtherNet/IP; CSMA/CD access method is used.

Wiring & Installation:

Q: What are the required cable categories and maximum transmission distance between nodes?

A: Category 5 or 5e UTP/STP cable is required, with a maximum distance of 100 m.

Troubleshooting & Compatibility:

Q: What is the significance of the ERH flashing LED on the Ethernet unit?

A: The ERH LED indicates an error, often due to an address disagreement or configuration fault.

Replacement & Upgrades:

Q: What is the lifecycle status of the CJ1W-ETN21, and is there a recommended replacement?

A: The unit is officially discontinued; replacement information should be verified with the manufacturer.