[Answer] What Is Programming for Industrial Programmable Logic Controllers (PLCs)?

[Answer] What Is Programming for Industrial Programmable Logic Controllers (PLCs)?

A PLC is an electronic device that was originally designed to replace relay circuits. Traditional relay control circuits are fairly complex and not easy to maintain. PLCs replace the hardwired wiring work of relay circuits with software programming, while retaining only the necessary input and output interfaces externally. This helps avoid the inconvenience caused by relay circuits during design, wiring, and maintenance.

Later, as technology continued to advance, the range of PLC applications gradually expanded beyond simple relay control circuits, inheriting advanced functions such as PID regulation and motion control.

PLC programming was also designed for engineers rather than programmers. According to IEC standards, PLCs can be programmed using different languages such as ladder diagrams, STL, and function blocks. Among these, the most widely used is still the ladder diagram, a language developed by visually transforming relay circuits. For experienced engineers, it is the easiest to adapt to and learn.