Design control program for a vending machine using PLC,
including wiring diagram, SFC, initial condition, transition, state, output, timer, counter if needed
Technical Requirements:
1.There are three kinds of beverage in the vending machine and only coins can be inserted into the machine, e.x. 1$, 5$, 10$.
2.When more than 3$ are inserted, the light of seven up is on. When more than 5$ are inserted, the lights of seven up and cola are on. When more than 7$ are inserted, the lights of seven up, cola and mineral water (Evian) are on.
3.When any button of beverage is pressed, it takes 7s to eject one tin of beverage.
4.To give change, one button has to be pressed. When the change is more than 3$, the light of seven up is still on. Similarly, when the change is more than 5$, the lights of seven up and cola are on. When press the button for giving change, all the lights are off.