In this article we will cover every PLC programming language in TIA Portal V20.
We have following options depending of PLC type :
S7-1200 G1 and G2 supports following programming languages:
- LAD – Ladder Logic LAD – Ladder Logic
- FBD – Function Block Diagram
- SCL – Structured Control Language
- CEM – Cause Effect Matrix
S7-300/400 supports these plc programming languages:
- LAD – Ladder Logic
- FBD – Function Block Diagram
- SCL – Structured Control Language
- STL – Statement List
- GRAPH – Graphical programming language
S7-1500 supports programming languages
- LAD – Ladder Logic
- FBD – Function Block Diagram
- SCL – Structured Control Language
- STL – Statement List
- GRAPH – Graphical programming language
- CEM – Cause Effect Matrix
Our example control system will stop and start fan and indicate a fan running with a lamp. Motor and lamp will switch ON when start button is pressed. When stop button is pressed, Motor contractor will switch off but lamp will continue to be on for 5 seconds.
Lets start with Ladder Logic.
LAD – Ladder Logic
a program that is represented by a graphical diagram, which is based on a circuit diagram of relay logic. part of IEC 61131-3 Standard.
– Power flows from the left rail to the right rail.
– If the logical conditions on a rung are satisfied, the corresponding output is triggered.
And program below:
FBD – Function Block Diagram
a graphical programming language used for designing control logic in Programmable Logic Controllers (PLCs) standardized by IEC 61131-3 for industrial automation programming.
– Programs are created using interconnected blocks that represent different functions.
– Data flows from left to right through function blocks.
– The focus is on how data moves between input and output blocks.
SCL – Structured Control Language
a high-level textual programming language used in Siemens PLCs, particularly within the TIA Portal development environment. It is based on Structured Text (ST), which is standardized by IEC 61131-3. SCL is designed for complex PLC programming tasks involving data manipulation, calculations, and advanced logic.
CEM – Cause and Effect Matrix
a programming language starting with TIA version 17. CEM provides a graphical interface that allows engineers to define and visualize the relationships between specific causes (input conditions) and their corresponding effects (output actions) in a matrix format. Can be only used in FBs – Functions blocks
STL – Statement List
low-level, text-based programming language, corresponding to the “Instruction List” language defined in the IEC 61131-3 standard. It allows for precise control over the CPU by enabling direct manipulation of processor operations. STL is primarily used with the S7-300 and S7-400 PLC series.
STL is not supported by the S7-1200 series, and the S7-1500 series emulates it to maintain compatibility with legacy code.
GRAPH
graphical programming language designed for implementing sequential control systems. It allows engineers to represent complex processes as flowcharts, enhancing clarity and simplifying the development of automation sequences.
Video is available with process of creating each program:
More about TIA Portal V20 and PLC programming languages: