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CJ Series Loop CPU Unit


Integrated Loop Control and Sequence Control

Introducing the New Style of Loop Control
Advanced controller functions integrated with the same CJ-series functionality and high-speed capabilities

CJ1G-CPU4[]P Features 1

Integrated Loop Control and Sequence Control

An engine for controlling analog quantities (e.g., temperature, pressure, flowrate) is built into the CPU Unit together with the engine for executing sequence control, delivering high-speed sequence control and high-speed, advanced analog quantity control in a single Unit.

CJ1G-CPU4[]P Features 2



Super compact: Only 90 mm High and 65 mm Deep, and Backplane-free structure enables flexible width design.

Compact PLC Aids Machine Downsizing by Fitting Just About Anywhere.
Wide Array of I/O Units, Special I/O Units, and CPU Bus Units Are Available to Suit Your Application.

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High-speed sequence control functions can be used directly for high-speed, advanced loop control.

  • Sequence control: Executes 20-Kstep ladder programs in 1 ms (with basic instructions only).
    PCMIX = 7.4 LD or OUT executed in 40 ns
  • Loop control: Executes PID operations for 20 loops in up to 10 ms. This is a guide for general applications. (See note.)
Note: Loop configuration: Ai4 Terminal + Segment Linearizer + Basic PID + Ao4 Terminal
          The external I/O response time in the overall system refers to the conversion time.


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CJ1G-CPU4[]P Features 9

Easy Engineering


Function blocks make loop-control programming easy. You can also create CX-Process Tool tuning windows to help adjust loops. Controller faceplates can be created automatically for touch panel displays.

Sequence control programs

Standardize and simplify programs using structured programming. Special I/O Unit and CPU Bus Unit settings are easy with function blocks (using ladder programming language or structured text).

Loop control programs:

By combining function blocks, a wide array of control methods can be easily configured, from basic PID control used by Temperature Controllers to program, cascade, and feed-forward control. Easily display values, such as temperatures, in engineering units, allowing you to check operation.

Engineering Example: Program Control

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Lineup includes low-cost models that use up to 50 function blocks and models that allow up to 300 blocks designed for large-scale systems and complicated operations.

Loop control:

Programming with function blocks to suit the application.

System configuration:

Choose and combine functions from a broad selection of I/O Units.

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High Reliability


Simply turn the DIP Switch ON/OFF to save or read the user program including function blocks using the Memory Card.

  • Simple backup function enables backup, recovery, and comparison of all PLC data including the function block programs for the Loop Control Board using the Memory Card.
  • Save tag settings, comments, annotations, and connection data created using the CX-Process Tool to either a Memory Card or a Loop-control CPU Unit.
    Note: Supported by unit version 3.0 or later.

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Consolidating OMRON's expertise in temperature and process control cultivated over many years to provide you with effortless solutions using proven algorithms.

Loop control:

Proven functionality of Temperature Controllers and CS-series Loop Control Boards in a compact size.

New Algorithm Further Enhances Control Stability
Disturbance Overshoot Adjustment

This function restrains overshoot when a disturbance is generated, allowing faster stabilization.
• Temperature drops when adding objects to a furnace
• Control disturbances when retooling

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Optimum Tuning to Suit the Application
Fine Tuning

Adjust PVs, SPs, and MVs while monitoring, and save data as CSV files from the software tuning window.
Autotuning (AT) and fine-tuning functions can also be used for automatically calculating PID constants (see note 2).

Note 1: For details on CS-series Loop Control Boards, refer to the PLC-based Process Control Catalog (Cat. No. P051).
         2: Control can be fine-tuned by automatically tuning PID parameters using previous control parameters and three
               user-set requirements to execute fuzzy logic.

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