Omron CJ1G-CPU45H High-Performance CPU Unit for CJ-Series PLCs Version 4.0

The Omron CJ1G-CPU45H is a high-performance CPU unit for the CJ-series programmable logic controllers. It is part of the CJ1G family, offering enhanced processing speed and expanded memory for complex control applications. This CPU operates with version 4.0 firmware, providing advanced functionality including increased program capacity and support for more extensive I/O configurations. The CJ1G-CPU45H is designed for machine control, process automation, and manufacturing systems requiring high-speed logic execution.

Processing Performance

The CJ1G-CPU45H utilizes a high-speed RISC processor optimized for ladder logic execution. Basic instruction execution speed: 0.02 µs per instruction. Special instructions execute at speeds ranging from 0.02 to 1.2 µs depending on the instruction type. The CPU processes interrupt tasks with response times as fast as 100 µs, enabling deterministic reaction to external events. The CPU supports up to 128 tasks, including cyclic tasks, interrupt tasks, and power-on tasks, allowing structured programming and separation of control logic.

Memory Configuration

Program memory capacity: 60K steps maximum (user ladder program). Data memory: 32K words DM (Data Memory), 32K words EM (Extended Memory) in the CJ1G-CPU45H configuration. EM memory can be divided into multiple banks, accessible via bank switching. The CPU also includes holding relay areas and work areas for general-purpose data storage. Real-time clock with battery backup maintains time-stamping accuracy for events and data logging. Firmware version 4.0 optimizes memory access and supports larger programs than earlier versions.

I/O Capacity

The CJ1G-CPU45H supports up to 2,560 I/O points per system when fully expanded with CJ-series I/O units. Combined with expansion racks, the system can accommodate up to 2,048 I/O points in the main CPU rack plus additional points in expansion racks. The CPU supports a mix of digital, analog, temperature control, and specialty I/O modules. Maximum number of connected units: up to 2,048 I/O points with 128 bytes each of input and output allocation. The CPU can control up to 2,560 total I/O points when using advanced configurations.

Built-in Functions

The CJ1G-CPU45H integrates several high-performance features without requiring additional modules. High-speed counters: 4 axes support single-phase counting up to 50kHz or differential-phase counting up to 30kHz. Pulse outputs: 2 axes with maximum 100kHz output frequency for direct control of stepper motors or servo drives via pulse train. These built-in functions include positioning instructions such as SPED, PULS, and PLS2 for speed control, absolute positioning, and acceleration/deceleration profiles. The CPU also supports interrupt inputs for immediate response to external events.

Communication Ports

Peripheral port: Round 6-pin connector for connection to CX-Programmer software, programming consoles, or HMIs. RS-232C port: 9-pin D-sub connector supporting Host Link, No-Protocol, or serial communication with external devices. Both ports can be used simultaneously, with the peripheral port typically dedicated to programming and the RS-232C port used for operator interface or device communication. Baud rates up to 115,200 baud are supported on the RS-232C port. High-speed Host Link communication (SYSMAC LINK) can be achieved using optional units.

Firmware Version 4.0

Version 4.0 firmware included with the CJ1G-CPU45H provides several enhancements over previous versions. It improves the performance of floating-point operations and enhances function block execution speed. It also expands the instruction set with new high-level math instructions and string handling functions. The firmware fully supports CJ-series high-function modules, including motion control units, position control units, and EtherNet/IP units. It is backward compatible with programs written for earlier firmware versions.

Hardware Specifications

Dimensions: 31 mm width x 90 mm height x 65 mm depth (CJ-series standard). Current consumption: 0.30A at 5V DC from CJ backplane. Weight: 120 g. Mounting: Plugs into any CJ-series CPU rack slot (slot 0 typically for CPU). The CPU has an SD card slot for program storage, data logging, and PLC initialization. A replaceable lithium battery maintains RAM and clock data during power interruptions, with battery life of approximately 5 years at 25°C.

Environmental Specifications

Operating temperature: 0°C to 55°C. Storage temperature: -20°C to 75°C. Humidity: 10% to 90% non-condensing. Vibration resistance: 2g at 10 to 57 Hz, 2 hours in each of 3 axes. Shock resistance: 15g for 11 ms, 3 times in each axis. Pollution degree 2 (in-panel installation). The unit is CE marked, UL/cUL recognized (File E318109), NK, LR, and RoHS compliant. It conforms to EN 61131-2 for programmable controllers.

Software Compatibility

The CJ1G-CPU45H is programmed using Omron CX-Programmer software (version 9.0 or later recommended for full functionality with version 4.0 firmware). Languages supported include Ladder Diagram, Structured Text, Instruction List, and Sequential Function Chart. The CPU can communicate with CX-Programmer via the peripheral port (USB-serial adapter required) or through an Ethernet network when connected via Ethernet unit. Online editing allows modifications to the running program without stopping control.

Applications

Typical applications include packaging machinery, high-speed assembly equipment, material handling systems, web processing, and machine tool control. The CPU’s high-speed processing and built-in positioning functions make it suitable for applications requiring coordinated motion and high-speed I/O response. The large program memory supports complex sequences and extensive error handling.

Conclusion

The Omron CJ1G-CPU45H universal CPU unit provides a balance of processing power, memory capacity, and built-in functions for mid-range CJ-series applications. Version 4.0 firmware ensures compatibility with the latest high-function modules and programming features, while the high-speed execution and extensive I/O capacity support a wide range of industrial control requirements.