Introduction into IEC 1131-3 and PLCopen

Modern programming methods provide tools to improve the intrinsic quality of software, i.e. its correctness in the sense of reliability, robustness, integrity, persistence, and safety. The international standard IEC 1131-3 provides such a tool, dealing with the programming, installation and maintenance phases of software development projects in industrial control. Basically, IEC 1131-3 consists of two parts, i.e. common elements and programming languages. The structuring tools within IEC 1131-3 are focused on the common elements, although clearly links to the programming languages are needed. The article shows that by using IEC 1131-3 in a consistent way, one can generate software code that is better understandable, reusable, verifiable and maintainable