Omron

Omron CS1W-ETN21 CS Series Ethernet Unit

SKU CS1W-ETN21

In stock
  • 12-month warranty
  • Free returns within 30 days
  • Manufacturer: Omron

  • Product No.: CS1W-ETN21

  • Country of origin:Japan

  • Product Type: Ethernet Communication Modules

  • Payment: T/T, Western Union

  • Weight: 1200g

  • Dimensions: 35 mm x 130 mm x 101 mm

  • Shipping port: Xiamen

  • Warranty: 12 months

Description

Integrating programmable logic controllers into enterprise networks requires reliable, high-speed communication interfaces. The Omron CS1W-ETN21 is a robust Ethernet unit designed specifically for the Omron CS-series PLCs. Acting as a CPU Bus Unit, this module provides 100BASE-TX (and 10BASE-T) communication interfaces to seamlessly bridge your industrial automation setup with local area networks, SCADA systems, and high-level industrial software.

With its robust support for various protocols and communication services, the CS1W-ETN21 enables advanced operations such as FINS (Factory Interface Network Service) communications, TCP/IP and UDP/IP socket services, and an integrated FTP server. This versatility allows engineering teams to perform remote programming, diagnostics, and high-capacity data transfers with minimal system overhead.

Features

  • Compatible with Omron CS1-series PLC systems as a CPU Bus Unit.
  • Supports dual-rate physical connections: 100BASE-TX and 10BASE-T.
  • Supports up to 4 Ethernet modules per CPU system (including Expansion Racks) for scalable network architectures.
  • Embedded FTP server functionality allows direct file transfers of PLC memory files.
  • Enables FINS messaging over both TCP/IP and UDP/IP protocols.
  • Comprehensive diagnostic and monitoring capabilities through integrated status LEDs.

Applications

  • High-speed manufacturing data collection and factory-floor integration.
  • SCADA and HMI communications in automotive, food & beverage, and material handling systems.
  • Remote PLC programming, monitoring, and program backup operations.
  • Data exchange between disparate distributed control systems over Ethernet networks.

Technical Specifications

Manufacturer Omron
Model / Part Number CS1W-ETN21
Unit Classification CS-series CPU Bus Unit
Physical Layer 100BASE-TX, 10BASE-T
Transmission Media Category 5 or higher twisted-pair cable (shielded)
Maximum Number of Units 4 units maximum (including Expansion Racks)
Current Consumption 380 mA maximum at 5 V DC
Supported Services FINS communications (TCP/IP and UDP/IP), FTP server, Socket services, Mail send/receive, DNS client
Dimensions (W x H x D) 35 mm x 130 mm x 101 mm

Connections and Interfaces

Interface / Indicator Description
RJ45 Port 8-pin modular connector for 100BASE-TX/10BASE-T Ethernet connection
RUN LED Green indicator showing normal unit operation status
ERC LED Red indicator signaling an internal unit error or configuration issue
ERH LED Red indicator signaling an error in CPU Bus Unit communication or setup
LNK/ACT LED Yellow indicator displaying network link establishment and transmission activity

Installation Guidelines

  • Ensure the PLC rack power supply is completely switched off before inserting or removing the Ethernet unit.
  • Securely mount the unit into the assigned CPU Bus Unit slot on the CS1 CPU Rack or Expansion Rack.
  • Use high-quality shielded twisted-pair (STP) Category 5 (or higher) cables for 100BASE-TX connections to prevent electromagnetic interference in high-noise environments.
  • Properly ground the PLC rack system to the industrial-grade earth ground terminal to stabilize communications and prevent transient voltage damage.

Compliance and Certifications

  • CE Compliant
  • UL Listed
  • cULus Certification

FAQ

What is the primary function of the Omron CS1W-ETN21 Ethernet unit?

The Omron CS1W-ETN21 is a CS-series CPU Bus Unit that provides 100BASE-TX/10BASE-T Ethernet connectivity for Omron CS1-series PLC systems, enabling high-speed FINS communications, FTP file transfers, and socket services.

How many CS1W-ETN21 units can be installed on a single CS-series system?

A maximum of 4 Ethernet units can be mounted per CS-series PLC system, including those located on the main CPU Rack and any attached Expansion Racks.

What is the current consumption of the CS1W-ETN21 module?

The module has a maximum current consumption of 380 mA at 5 V DC, drawn from the internal power supply of the PLC backplane.

Does this Ethernet unit support remote programming and monitoring?

Yes, using Omron CX-Programmer or Sysmac Studio over FINS TCP/IP or UDP/IP protocols, you can perform comprehensive remote programming, debugging, and diagnostics.

View all FAQs →

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Shipping & Returns

Global Express Shipping

  • Standard Delivery: 4–6 business days via DHL, FedEx, and UPS.
  • Express Dispatch: Same-day dispatch for in-stock orders placed before 2:00 PM (GMT+8).
  • Worldwide Coverage: Serving over 150 countries.

Returns & Warranty

  • 30-Day Guarantee: Returns accepted for in-stock products in original, factory-sealed packaging.
  • 12-Month Warranty: Every industrial component is backed by our technical warranty.
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Global Express Shipping

  • Standard Delivery: 4-6 Business Days via DHL, FedEx, and UPS.
  • Express Dispatch: Same-day dispatch for in-stock orders placed before 2:00 PM (GMT+8).
  • Worldwide Coverage: Serving over 150 countries, including rapid delivery to Saudi Arabia and UAE.

Returns & Warranty

  • 30-Day Guarantee: Returns accepted for in-stock products in original, factory-sealed packaging.
  • 12-Month Warranty: Every industrial component is backed by our professional technical warranty.

Orders are processed and delivered Monday-Friday (excluding public holidays).


For full eligibility, restocking fees, and international return details, please view our official Refund & Return Policy .

TECHNICAL SPECIFICATIONS

Country of origin
Japan

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