Omron CP1H & Mitsubishi MR-J4 Servo Control: Jog Process Tutorial

Introduction:

In this tutorial, we will continue exploring the use of the Mitsubishi MR-J4-A servo drive in conjunction with the Omron CP1H PLC, focusing on implementing a “Jog Process” for position control. This guide builds on our previous discussion, where we covered the “ORG Search” and “Position Control.” functionality. Now, we will dive into creating a “Jog” program to detect and control servo position. Notably, the CP1H and many other Omron PLCs using the CX-Programmer do not have a native Jog instruction, so we will implement a custom solution.

• CP1H & MR-J4-A “ORG Search”
• CP1H & MR-J4-A “Position Control”

1. Connection Diagram

To facilitate the Jog process, we will use two additional hardwired buttons for Jog (+) and Jog (-) controls. These buttons will be connected as per the diagram used in the “ORG Search” tutorial.

Connection Diagram for Jog (+) and Jog (-) buttons

Explanation:

• Jog (+) Button: Connected to input 003.
• Jog (-) Button: Connected to input 004.
• Purpose: These buttons will allow manual jogging of the servo motor in both positive and negative directions.

2. Programming the Jog Process

To implement the Jog functionality, we will use the PLS2 (Pulse Output) command in the CX-Programmer. Below are the steps and parameters required to configure the Jog process.

Step-by-Step Programming:

1. PLS2 Command Setup:
   • Port: #0000
     • Explanation: This specifies the output port used for pulse generation.
   • M Parameter: #0101
     • Explanation: Indicates Pulse + Direction & Absolute pulses mode.
   • S > S+5: D100 > D105
     • Explanation: These data registers will store the start address and parameters for the pulse output.
   • F > F+1: D106 > D107
     • Explanation: These registers will control the frequency of the pulses, determining the speed of the Jog operation.
2. Program Logic:
   • Jog (+) Process:
     • When the Jog (+) button is pressed, the program sends a series of pulses in the positive direction to the MR-J4-A servo drive, causing the motor to move forward.
   • Jog (-) Process:
     • When the Jog (-) button is pressed, pulses are sent in the negative direction, moving the motor in reverse.

Example of PLS2 command setup in CX-Programmer

3. Jog Process:

The Jog process involves generating a specific number of pulses to move the servo motor incrementally. By adjusting the pulse count and frequency, you can control the distance and speed of the servo’s movement.

Example of Jog Process

4. Pulses Output:

• Pulse Frequency: This determines how fast the servo motor moves during the Jog operation.
• Pulse Count: This controls the distance the motor will travel in response to each button press.

Example of Pulse Output Configuration

Conclusion

By following these steps, you can effectively implement a Jog process using the Omron CP1H PLC and the Mitsubishi MR-J4-A servo drive. This approach allows for precise manual control over servo position, even in the absence of a native Jog instruction within CX-Programmer. This setup is especially useful in applications requiring fine-tuned manual adjustments of servo positions.

This tutorial provides the foundational knowledge needed to set up a Jog process. For further customization or advanced implementations, refer to additional resources or consult with automation professionals.