Overview: Two Categories of Five Languages Graphical Languages (Intuitive, similar to drawing) Ladder Diagram (LD) – The most commonly used, suitable for logic control. Function Block Diagram (FBD) – Suitable for process control. Sequential Function Chart (SFC) – Suitable for sequential processes. Textual Languages (Similar to writing code) Structured Text (ST) – Powerful, suitable for … Read more
What is a PLC Sequential Function Chart? A sequential function chart is a graphical representation method that describes the process, functions, and characteristics of a sequential control system. It mainly consists of steps, directed segments, transitions (including transition conditions), and actions. Understanding and mastering each component is crucial for drawing a good sequential function chart. … Read more
01Ladder Diagram (LD) · Features: A graphical language similar to electrical relay circuit diagrams, suitable for logical control. · Application Scenarios: Switch logic familiar to traditional electrical engineers (e.g., motor start/stop, interlocking control). 02Instruction List (IL) · Features: A low-level text language similar to assembly, consisting of operation codes and operands. · Application Scenarios: Small … Read more
Click the little blue text to follow! Last week, during a safety assessment at an automation factory, I witnessed their equipment experiencing an inexplicable shutdown. The manager looked worried and said, “This is the third time this month, and each shutdown costs us over a hundred thousand.” Where is the problem? After inspection, I found … Read more
Search on WeChatTechnical Training The programming languages for PLCs have distinct characteristics compared to general computer languages; they are neither high-level languages nor typical assembly languages, and they must meet the requirements of being easy to write and debug. Early PLCs only supported Ladder Diagram (LD) and Instruction List (IL) programming languages. Currently, the International … Read more
There are currently 5 standard programming languages for PLCs, including graphical and textual programming languages. Graphical programming languages include: Ladder Diagram (LD); Function Block Diagram (FBD); Sequential Function Chart (SFC). Textual programming languages include: Instruction List (IL) & Structured Text (ST). IEC 1131-3 programming languages are a set of international programming language standards for industrial … Read more