Learn New Knowledge! Detailed Explanation of Mitsubishi PLC [Rotary Table Control] Functionality.

I accidentally came across this instruction, and today we will discuss a convenient instruction “ROTC” in the Mitsubishi FX3U PLC. Its function is: for our rotary table equipment, the number of divisions can be set, and among them, one or two positions can be processed. We can intelligently determine the fastest rotation direction through this instruction and automatically find the fastest path for positioning.For example: Workstation 1 and Workstation 2 currently correspond to division positions 0 and 1. When I want to rotate to Workstation 1 from the 8 division position, inputting the corresponding parameters will cause it to reverse, only needing to turn 2 divisions, while a forward rotation would require 8 divisions. The purpose is to select the shortest path and achieve our target workstation with acceleration and deceleration functions.Schematic Diagram:

Next, let’s explain this principle in detail.

1. Instruction Format

This instruction is also called shortcut control, used to access items on a cyclic table divided by m1, based on the request access window to make the cyclic table’s near-path loop instruction.

2. Instruction Details

D100: Call condition word register [Starting Address]

K10: Number of divisions of the rotary table

K2: Low-speed operating range

M0: Call condition bit register [Starting Address]

D100 Explanation: (According to the program written, it is not fixed as D100)

D100 is the starting address, which will call D100, D101, D102 three words

Among them:

D100: Used to count the arrival of which workpiece at window 0

D101: Where we currently need to rotate the workpiece to which workstation, Workstation 1 or Workstation 2

D102: Which workpiece number (0-9) we need to call on the division position

K10 Explanation: The number of divisions of the rotary table, which is easy to understand.

K2 Explanation: For example, if D102=5, D101=1, it needs to rotate 5 times, then when there are 2 divisions left, it will run at low speed, while the previous 5-2=3 divisions will run at high speed.

M0 Explanation: (According to the program written, it is not fixed as M0)

M0 is the starting address, which will call M0, M1~M7 a total of 8 bit addresses

Among them:

It is necessary to design dual-phase switches (X0, X1) for detecting the forward/reverse rotation of the workbench, and the origin sensor X2.

M0: A phase sensor X0 has a signal, M0=ON, no signal from X0, M0=OFF.

M1: B phase sensor X1 has a signal, M1=ON, no signal from X1, M1=OFF.

M2: 0 division position, the rotary table needs to design a sensing position for the origin (protrusion), using the origin sensor X2 for sensing.

After specifying the above conditions, in the starting soft elements of the instruction specified +3 to +7 outputs, we can obtain outputs for forward/reverse rotation, high-speed/low-speed/stop, etc.

Let’s first design the Y outputs on the device.High speed forward – Y0, low speed forward – Y1, rotary table stop – Y2, low-speed reverse – Y3, high-speed reverse – Y4.

M3: M3=ON, Y0=ON, M3=OFF, Y0=OFF. High-speed forward

M4:M4=ON, Y1=ON, M4=OFF, Y1=OFF. Low-speed forward

M5:M5=ON, Y2=ON, M5=OFF, Y2=OFF. Stop

M6:M6=ON, Y3=ON, M6=OFF, Y3=OFF. Low-speed reverse

M7:M7=ON, Y4=ON, M7=OFF, Y4=OFF. High-speed reverse

Refer to the diagram below:

3. Program Implementation

1. Define IO:

2. Define Registers:3. Program Writing A total of 36 lines, I will not attach the source program here, everyone can simulate and test.4. Summary

• First, understand the hardware composition of the rotary table
• Clarify the instruction format
• The meaning of each register in the instruction format
• How the program is implemented.

I also saw this instruction while looking at materials for learning. Everyone can understand and learn about it. Although we may use it less in practice, it is indeed very convenient when we can use it. If you encounter any problems during the learning process, feel free to communicate in the comment area.If you like it, you can follow or bookmark it.Below are related series of learning articles, hoping to provide some help:Beginner Project [Automatic Screw Machine] C#, PLC, Touch Screen Practical (1/5): Electrical Preliminary DesignEssential for Electrical Newcomers! Quick Start PLC Projects: Detailed Breakdown of 7 Steps!Beginner Project [OpenCV Visual Sorting Robot Arm] (1/3): Program Design. [C# Winforms, OpenCV Vision, PLC Practical]