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Programming methods of IEC61131-3
The IEC61131-3 standard defines 5 programming methods for PLCs:
- Ladder diagrem (LD)
- Functional block diagram (FBD)
- Structured text (ST)
- Instruction list (IL)
- Sequential function chart (SFC)
Functional block diagram (FBD)
Function Block diagram is a programming method, which allows easy graphical programming via pre-programmed function blocks. Those blocks are to be interconnected with other blocks or input / output variables. Each function block describes the relation between the input and output variable. It is possible to either import FB or make your own.
