Omron CJ1W-NC481 4-Axis EtherCAT Position Control Unit

Technical Overview

The Omron CJ1W-NC481 is a CJ-series high-speed Position Control Unit (PCU) equipped with an EtherCAT interface. Designed for seamless integration into Omron CJ-series programmable logic controllers, it is capable of managing up to 4 servo axes with exceptional precision. Utilizing a 100 Mbps EtherCAT network, it achieves an ultra-fast control cycle of 0.5 ms and a rapid startup time of 0.15 to 0.4 ms. With comprehensive support for both direct and memory operation, including advanced 4-axis linear and 2-axis circular interpolation, the CJ1W-NC481 reduces wiring complexity while maximizing multi-axis motion synchronization in high-performance industrial machinery.

Key Features

EtherCAT network interface with 100 Mbps communication speed
Multi-axis support for up to 4 independent servo axes
Ultra-fast startup time of 0.15 to 0.4 ms from PLC command
Fastest control cycle of 0.5 ms for high-precision motion tasks
Supports 4-axis linear interpolation and 2-axis circular interpolation
Allows memory operation or direct operation via standard ladder programming
Directly compatible with Omron G5-series Servo Drives with built-in EtherCAT
Compact 31 mm width footprint for space-saving panel design

Technical Specification Matrix

Parameter	Value
Number of Controlled Axes	4 axes max
Communication Interface	EtherCAT (100BASE-TX)
Baud Rate	100 Mbps
Memory Capacity	16-bit (1 word)
Max Command Output Speed	104 Mpps
Linear Interpolation	Up to 4 axes max
Circular Interpolation	Up to 2 axes
Internal Current Consumption	460 mA max. at 5 VDC
Ambient Operating Temperature	0 to 55°C
Dimensions (H x D x W)	90 mm x 65 mm x 31 mm
Weight	110 g max.
Applicable PLCs	Omron CJ Series

Industrial Applications

1. High-Speed Synchronization in Packaging Lines

The CJ1W-NC481 connects a master CJ-series PLC to servo drives over a 100 Mbps EtherCAT network, allowing for extremely precise synchronization of 4 independent axes (such as feeders, rotary cutters, and sealers). The ultra-fast 0.5 ms control cycle and 0.15 ms startup time make it ideal for rapidly moving automated packaging lines that require on-the-fly corrections.

Problem Solved

Reduces communication lag and position jitter between multi-axis mechanisms in high-speed form-fill-seal machines, directly minimizing material waste and mechanical wear.

EtherCAT4-Axis Position ControlLinear Interpolation0.5 ms Control Cycle

2. Multi-Axis CNC Machining and Cutting

Employing its linear (4-axis) and circular (2-axis) interpolation capabilities, the CJ1W-NC481 accurately manages the complex X-Y-Z tooling paths for automated cutting, milling, or routing equipment. Utilizing internal memory operation and up to 104 Mpps command output speeds, it maintains strict spatial coordinates across complex machining curves.

Problem Solved

Replaces expensive, dedicated external motion controllers by natively integrating advanced multi-axis path logic directly into the standard PLC backplane without sacrificing sub-millisecond precision.

Circular InterpolationMulti-Axis Synchronous Control104 Mpps Command SpeedMemory Operation

3. Robotic Pick-and-Place Gantry Control

Deployed in material handling, the CJ1W-NC481 dictates the exact motion profiles of a 4-axis Cartesian gantry robot. Generating a minimal 460 mA current load on the 5 VDC PLC bus, it easily coordinates 4 networked servo drives using standard shielded RJ45 EtherCAT cabling over node-to-node distances up to 100 meters.

Problem Solved

Simplifies massive control cabinet wiring architectures in distributed material handling systems, ensuring collision-free, synchronized positional adjustments over long-distance plant layouts.

Distributed Motion Control100BASE-TXCartesian Robot ControlPosition Control Unit (PCU)