PLC programming language is a language used to write PLC programs in the field of industrial control, aiming at realizing the automated control and monitoring of industrial equipment and production processes.PLC programming language contains many types of languages, such as graphical programming language, textual programming language, structured programming language, etc., which can be selected and combined according to different application scenarios and programming needs.C is a universal computer C is a general-purpose computer programming language. The following are the main differences between them:
1. application environment: PLC programming language is mainly used in the field of automation control, while C language is suitable for various computer applications.
2. Syntax structure: PLC programming language adopts graphical programming, while C language adopts textual programming. 3. data type: PLC programming language adopts graphical programming, while C language adopts textual programming.
3. Data types: PLC programming language supports different data types, such as bit, word, floating point, etc., while C language supports more data types, such as integer, long integer, character, floating point, double precision, etc.
4. Program execution mode: PLC programming language executes the program in a cyclic scanning mode, while C language executes the program in a sequential execution mode.
5. Unit Operators: PLC programming language supports Boolean operators such as and, or, not, etc., while C supports richer operators such as incremental, decremental, bitwise operations etc.
According to the difference between PLC and computer system, there are some additional features in PLC programming language, such as input/output processing, timer/counter operation, etc.
The main international standards for PLC programming languages include the IEC 61131-3 standard and the IEC 61499 standard.
The IEC 61131-3 standard defines five PLC programming languages, which are Instruction List (IL), Structured Text (ST), Function Block Diagram (FBD), Flowchart (LD) and Sequence Chart (SFC). This standard mainly specifies the basic requirements for PLC programming, such as program syntax, data types, program functions, etc., to ensure a certain degree of compatibility and portability of the program languages of different PLC manufacturers.
The IEC 61499 standard is an extension and refinement of the IEC 61131-3 standard. It provides a PLC programming language for Distributed Control Systems (DCS), which introduces new concepts and models, such as function blocks (FBs), agents and events. This standard focuses on the flexibility, scalability and reusability of PLC systems.
Both standards were developed by the International Electrotechnical Commission (IEC) and are important regulations and specifications for PLC programming languages.