Which type of programming is commonly used for PLCs?

Sequential Function Charts (SFC) is indeed a commonly used programming method for Programmable Logic Controllers (PLCs). This graphical programming language provides a clear and structured way of designing control processes by representing system operations as a sequence of steps and transitions. The visual nature of SFC allows engineers and technicians to easily understand and modify control sequences, making it particularly useful for process control and automation tasks.

SFC is part of the IEC 61131-3 standard for PLC programming, which defines several programming languages for industrial control systems, including ladder logic and structured text. The use of SFC supports better organization of complex control logic, facilitates debugging, and enhances communication among team members working on control systems.

The other options refer to programming methods that are either too broad or not primarily associated with PLC programming. High-level programming languages can be used in PLCs but are not the mainstay. Assembly language is too low-level for typical PLC applications, as it requires more detailed knowledge of hardware that is unnecessary for most PLC programming tasks. Basic mathematical computations, while essential in certain aspects of control logic, do not represent a programming method or paradigm in the context of PLCs.