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Learn PLCs from scratch, programming right in your browser
Clear theory, a simulator with Ladder and the IEC 61131-3 languages, animated processes and self-grading challenges.
Four learning paths
Go at your own pace, from your first contact to processes close to real industry.
Fundamentals
What a PLC is, how it works inside, the scan cycle and the types available.
ExploreHardware & wiring
Inputs and outputs, PNP and NPN sensors, wiring, ports and industrial protocols.
ExploreBrands & software
The main brands, their product lines, programming software and how they name addresses.
ExplorePractice
Simulator, examples with virtual plants and self-grading challenges.
Explore
Try it: motor start and stop
The classic seal-in circuit. Press START and STOP and watch power flow through the rung.
The motor contact, in parallel with START, keeps the circuit closed after you release the button: that is the seal-in (latch). STOP uses a normally closed contact, which opens when pressed and breaks the circuit.
Go to the full simulatorPress and hold