In some applications, it may be required to use one single push button in order to save inputs or for whatever reason to start and stop the same motor.
It is simple, all you need is to acquire an instruction that could register the output status (on or off), and upon the status of the output, it should decide the next action to on or off the output.
Note: The best practice to learn the PLC programming is to start writing the PLC program, take your time before you review the answer.
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Inputs & Outputs:
M0.0: Positive Trigger
M0.1: Negative Trigger
Start Stop of one Motor from same Push button
In this network you can find the SR flip flop where:
If the motor Q0.0 is OFF and the Push-button (PB) I0.0 is pressed for one time, the set value would be energized and sets the output Q0.0 to ON. So the motor will be started.
If the motor Q0.0 is ON and the PB I0.0 is pressed for one time, the reset value would be energized and sets the output Q0.0 to OFF. So the motor will be stopped.
The positive edge detector in the set branch is used to ensure that the press of the I0.0 should be executed for a single scan cycle.
The negative edge detector is to ensure that the reset should not be energized unless the motor is ON.
Author: Karim Ali Anwar
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