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PLC Programming Example for Motor Forward and Reverse Control

 Make the example ladder logic to control the motor in forward and reverse direction using PLC Programming with limit switches as sensors.

PLC Example for Motor

The Workpiece starts moving on the left side and moves to the right when the start button is pressed.

When it reaches the rightmost limit, the drive motor reverses and brings the workpiece back to the leftmost position again and the process repeats.

The forward and reverse pushbuttons provides a means of starting the motor in either forward or reverse so that the limit switches can take over automatic control.

Motor Forward and Reverse Control


List of Inputs and Outputs


Program Description

RUNG 0000

Latching rung to operate the system through Master Start and Stop PB.


RUNG 0001

When the workpiece is near Limit switch1, It will enable forward motor, for latching forward Motor is connected in parallel with limit switch 1.


Forward Pushbutton (PB) is also connected in parallel to manually operate forward motor.


RUNG 0002

When the workpiece is near Limit switch2, It will enable reverse motor, for latching reverse Motor is connected in parallel with limit switch 2.


Reverse Pushbutton (PB) is also connected in parallel to manually operate Reverse motor.


Conclusion:

The above-explained process is for example only. It may vary from real-time.


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