Introducing PLC programming languages
According to International Electrotechnical Commission (IEC) standards, there are five programming languages, stated in part 3 of IEC 61131, for writing a program for PLCs to control and automate a task. These programming languages are the following:
- Ladder Diagram (LD)
- Function Block Diagram (FBD)
- Sequential Function Chart (SFC)
- Instruction List (IL)
- Structured Text (ST)
IEC 61131-3 can be purchased at their web store at the following link. However, there is an abstract you can read and also a preview that can be downloaded for free:
https://webstore.iec.ch/publication/4552
Note
IEC is an international standards organization responsible for preparing and publishing international standards for all electrical, electronics, and other related technologies.
Let's discuss each of these programming languages in detail.
Ladder Diagram (LD)
This is most common among several PLC programming languages...
