Mitsubishi PLCs use multiple programming languages depending on the complexity of the control system and the series of the controller. The most common programming language used in Mitsubishi PLCs is Ladder Logic (LD). It is a graphical language that resembles electrical relay circuits, making it easy for engineers and technicians to understand and design industrial automation logic. Ladder Logic is widely used for simple control tasks like motor start-stop, interlocking, and safety sequences. Apart from that, Mitsubishi also supports Function Block Diagram (FBD) for modular control design, where functions are represented as blocks connected by signal lines. This is ideal for systems that need repeated or reusable logic blocks.
For more advanced applications, Mitsubishi PLCs support Structured Text (ST) and Sequential Function Chart (SFC) programming languages. Structured Text is a high-level language similar to C, which allows for writing complex arithmetic, conditional, or looping operations. Sequential Function Chart helps in designing processes that run in steps or sequences, such as automated packaging or robotic movements. Some older PLC models also support Instruction List (IL), which works like assembly language and is suitable for compact, low-level programming. The programming is done using Mitsubishi’s software tools like GX Works2 and GX Works3, where GX Works3 is the latest platform for MELSEC iQ-F and iQ-R series PLCs. Additionally, advanced controllers in the MELSEC iQ-R series can even be programmed using C or C++ for specialized, high-performance applications. In summary, Mitsubishi supports multiple programming languages—Ladder Logic, Structured Text, Function Block Diagram, Sequential Function Chart, and even C/C++—allowing engineers to choose the right one based on system complexity, performance needs, and personal preference.