Glossary · SCL
What is Siemens SCL?
The Siemens name for Structured Text in TIA Portal and STEP 7: IEC 61131-3 compatible with its own conventions.
The main differences: local variables are prefixed with #, global tags are written in quotes as "Tag", and the timers are called TON_TIME and TOF_TIME in optimized blocks.
The ST lab on this site exports your program as SCL ready to paste into TIA Portal, adding the # prefix and the correct block names.
Related terms
- Structured Text (ST)
- A textual programming language in IEC 61131-3 resembling Pascal, used for complex PLC logic, calculations and state machines.
- IEC 61131-3
- The international standard that unified PLC programming: five languages, the data types, the program organization units and the standard function blocks.