... — Iec 61131-3: Programming Industrial Automation

A high-level textual language similar to Pascal or C, ideal for complex algorithms and mathematical calculations .

A graphical language that uses interconnected blocks to represent logic, making it easy to build and visualize complex control flows. IEC 61131-3: Programming Industrial Automation ...

The IEC 61131-3 standard is the globally recognized authority for programming industrial control systems, specifically Programmable Logic Controllers (PLCs) . Established in the early 1990s, it ended the era of proprietary manufacturer languages, creating a unified framework that promotes interoperability and code reusability across different brands like Siemens, Rockwell, and Schneider Electric. A high-level textual language similar to Pascal or

A graphical language modeled after electrical relay logic, widely favored by electrical engineers for its intuitive, circuit-like structure. Established in the early 1990s, it ended the

A graphical method for structuring sequential processes , decomposing problems into defined steps and transitions.

The standard defines five distinct languages, categorized into graphical and textual formats:

Beyond languages, the standard provides a rigorous software model to ensure program stability: