About PLC Practice Lab

PLC Practice Lab is a browser-based trainer for learning ladder logic. It is aimed at individual learners, career starters and technicians reviewing control logic.

What it is

• Eight basic exercises: inputs, coils, series/parallel, self-latch, TON timer, CTU counter, sequencing, hysteresis.
• A vendor-neutral scan engine with a fixed 20 ms logic cycle.
• Automatic judging with specific failure messages and tiered hints.
• Local save, refresh restore, JSON export/import, and shareable links.
• No account, no login, no payment, no tracking.

What it is not

• Not an IEC-certified PLC and not compatible with any vendor's programming software.
• Not for controlling real machinery or production equipment.
• Not a Structured Text compiler, HMI builder, or robotics platform.

See Limitations for the supported scope and known boundaries. Interface layouts and ladder drawings are original to this project; it is not affiliated with PLC software vendors. See open source notices for bundled library licenses.