Omron C500-NC222 2-Axis Positioning Unit for SYSMAC C500 PLC Systems

Product Overview

The Omron C500-NC222 is a dedicated positioning unit designed for the SYSMAC C500 series programmable logic controllers. This module provides two independent axes of open-collector pulse train output, enabling precise control of stepper motors or servo drives. It is ideal for applications requiring coordinated motion, such as CNC routers, pick-and-place machines, and automated assembly systems.

Key Specifications

• Model: C500-NC222

• Product Series: SYSMAC C500 Special I/O Unit

• Number of Control Axes: 2 axes (independent or interpolated)

• Output Type: Open-collector pulse train

• Maximum Output Frequency: 100 kHz

• Positioning Range: -8,388,607 to +8,388,607 pulses

• Acceleration/Deceleration: Trapezoidal, programmable slopes

• Interpolation: Linear interpolation (2 axes)

• Positioning Methods: Absolute, incremental

• External I/O: 4 inputs (limit switches, home, external interrupt), 4 outputs (positioning complete, error)

• Power Supply: 5 VDC from backplane

• Dimensions: 1 slot width (approx. 35 mm)

Precision Motion Control

The C500-NC222 executes positioning sequences based on data stored in its internal memory or directly from the PLC. It supports both absolute and incremental positioning modes, with programmable acceleration/deceleration profiles to minimize mechanical shock. The unit also features automatic deceleration at the target position, ensuring smooth stops and high repeatability.

Linear Interpolation and Multi-Axis Synchronization

For diagonal or curved paths, the C500-NC222 provides 2-axis linear interpolation, allowing synchronized movement between the X and Y axes. This is essential for contouring applications in CNC machining or cutting tables. The unit also allows independent operation of each axis for simpler pick-and-place tasks.

PLC Integration and Programming

The positioning unit communicates with the C500 CPU via the I/O bus. Positioning commands (target position, speed, acceleration) are written to specific DM (Data Memory) areas, and the unit executes the move upon receiving a start command. Alternatively, pre-configured positioning sequences can be stored in the unit’s internal RAM and triggered by a single control word. This offloads real-time motion control from the main PLC processor.

External I/O for Machine Interfacing

Four dedicated inputs allow direct connection of limit switches, home sensors, or external interrupt signals, enabling accurate homing and emergency stop handling without PLC scan delays. Four outputs provide status signals to the PLC, such as positioning complete, error, or zone detection.

Industrial Applications

• CNC drilling and milling machines (2-axis table control)

• Pick-and-place equipment for PCB assembly

• Automatic soldering and dispensing robots

• Labeling and packaging machinery

Conclusion

The Omron C500-NC222 positioning unit extends the C500 PLC system with high-speed, precise motion control capabilities. Its open-collector pulse outputs, linear interpolation, and easy integration make it a cost-effective solution for 2-axis positioning applications.