Question: What is difference between SCL and STL?

What is Siemens SCL?

SCL stands for Structured Control Language and is a text-based form of programming Siemens PLCs.

What is SCL language?

SCL (Structured Control Language) is a high-level, Pascal-based programming language that enables structured programming. The language corresponds to the “Structured Text” (ST) programming language specified in DIN EN-61131-3 (IEC 61131-3).

What does SCL mean in PLC?

• PLC programming > SCL (Structured Control Language)

Is SCL structured text?

SCL is same as Structured Text like STL is same as Instruction List. I do not know why Siemens has named those languages like that. SCL and STL (german AWL ) are different languages having different syntax. Some things in SCL was taken from Pascal and adapted for usage in plc.

What are the 5 PLC programming languages?

The 5 most popular types of PLC Programming Languages are:

• Ladder Diagram (LD)
• Sequential Function Charts (SFC)
• Function Block Diagram (FBD)
• Structured Text (ST)
• Instruction List (IL)

How do you convert SCL to ladder?

With newer firmware that allow mixing Ladder and SCL in the same block, create a new ladder block, and insert “SCL”. Then paste in the SCL logic. Now you have a ladder block to hide the scl inside of.

What programming language does Siemens plc use?

Ladder logic (LAD) is one programming language used with PLCs. Ladder logic incorporates programming functions that are graphically displayed to resemble the symbols used in hard-wired control diagrams.

How do you program a PLC?

Step-By-Step Procedure for Programming PLC Using Ladder Logic

1. Step 1: Analyze and Get the Idea of Control Application. …
2. Step 2: List All the Conditions and Get the Design using Flowchart. …
3. Step3: Open and Configure the PLC Programming Software. …
4. Step 4: Add the Required Rungs and Address Them.

How do you write SCL?

Writing your first TIA code in SCL:

1. Step 1 – Create or open TIA project.
2. Step 2 – Add FB/FC.
3. Step 3 – Modify the block interface.
4. Step 4 – Enter SCL code.
5. Step 5 – Provide some data.
6. Step 6 – Call the FC in OB1.
7. Step 7 – Testing.
8. Step 8 – More generic approach.

What is FBD in PLC?

The Function Block Diagram (FBD) is a graphical language for programmable logic controller design, that can describe the function between input variables and output variables.

What is Siemens TIA Portal?

TIA Portal lets you integrate all the key components in your automation project, including safety, security, control, HMI, drives, decentralized peripherals, motion control, and power distribution.

How does ladder logic work?

Execution of Ladder Logic



Typically before starting to execute the logic, the CPU reads the physical inputs tied to the I/O modules to update their status in the CPU’s memory table. Then, starting at the top left of the program, the CPU works its way down the rail executing each rung or sub rung from left to right.