Engineering · PLC · Projects
PLC Project Library
Pick a machine, see the ladder, then run it and change it.
15 common industrial applications, from a motor start/stop to star-delta, tank level, conveyors, cylinder sequences and alarms. Each has a picture, the ladder diagram, structured text, tag addresses for seven PLC brands and a parts list, plus a button that opens it in the PLC Simulator.
Learning model only. This page teaches the program logic. A real machine needs a proper control panel with an isolator, fuses, motor protection and a hard-wired emergency stop. Mains and motor wiring is for qualified electricians. A PLC output never drives a motor directly.
Motor control3
Start, stop, reverse and ramp up a motor safely.
Level 11. Motor start / stop (seal-in)The most important rung in industry: press START, the motor keeps running by itself until STOP or an overload.
Level 22. Forward / reverse with interlockTwo contactors swap two phases to reverse a motor. The program must never let both close together.
Level 33. Star-delta starterStart a big motor gently in star, then switch to delta after a few seconds. Learn timers and three contactors.Process and level3
Tanks, pumps, temperature and filling.
Level 25. Automatic pump with float switchesKeep a tank between LOW and HIGH levels. The pump turns on when the tank is low and stops when it is full.
Level 311. Oven temperature on / off controlKeep an oven near 60 °C using a heater, a cooling fan and an analog temperature input.
Level 212. Bottle filling stationPlace a bottle, press START, the valve opens for 3 seconds and a DONE lamp lights until you remove the bottle.Sequences3
Step-by-step machines: valves, cylinders and presses.
Level 36. Tank filling and mixing (SFC)Fill with liquid A, fill with liquid B, stir for 5 seconds, then drain. A true step-by-step sequence.
Level 37. Two cylinders: A+ B+ B- A-Cylinder A extends, then B extends, then B retracts, then A retracts. The classic pneumatic sequence.
Level 314. Two-hand press controlA press only moves when both buttons are pressed together. Keeps hands out of the danger zone.Signals and alarms3
Lights, flashers and alarm handling.
Level 28. Traffic lightGreen, yellow and red in a repeating cycle using three chained timers.
Level 19. Flasher (blinking lamp)Two timers feed each other to blink a warning lamp. Used in nearly every alarm program.
Level 313. Alarm with acknowledgeA fault flashes a lamp and sounds a horn. Pressing ACK silences the horn; the lamp stays steady until the fault clears.Conveyors and doors3
Moving boxes, counting parts, opening doors.
Level 24. Conveyor with warning hornA horn sounds for 3 seconds before the conveyor starts, as required by safety rules.
Level 210. Part counter with batch stopCount boxes with a photo-eye. After 5 boxes the belt stops and a lamp lights until RESET.
Level 315. Roller door with safety beamOpen, close and stop a roller door. If something breaks the beam while closing, the door reverses.