Instruction is the PLC to be told what to do, and how to do code or symbol. Text and graphic symbols usually two.
Writing code for commonly used mnemonic form, known as the PLC statement table of instructions. It is similar to a computer‘s Assembly language, Ruby‘s initials and the number represents the corresponding directive.
Graphical symbols for commonly used for ladder diagram symbols, it is similar to the electrical schematic symbols, more easily acceptable to the electric staff, there is also logic chart symbols and flowchart symbol. Ladder diagram programming of PLC is the most important language.
PLC also have access to a high-level language, such as BASIC,C language, in fact, as long as appropriate compile software, what language can be used.
Most PLC and mnemonic instruction at the same time, also accepts a ladder diagram graphics directives, but want to use graphics programmer, or personal computer, and is equipped with the appropriate software.
A PLC instructions instructions for all known as the PLC system. It represents the performance or functionality of the PLC. Functions, properties PLC, its instruction set rich, energetic matter more.