可编程控制器 第3部分：编程语言

[中文适用范围]： IEC 61131-3:2025 规定了可编程控制器编程语言的语法和语义，这些语言在 IEC 61131-1 中有定义。本文件规定了一套统一的可编程控制器（PC）编程语言的语法和语义。该套语言包括文本语言结构化文本（ST）以及图形语言梯形图（LD）和功能块图（FBD）。此外，还定义了一组名为顺序功能图（SFC）的图形和等效文本元素，用于组织程序和功能块的内部结构。同时，还定义了配置元素，以支持将可编程控制器程序安装到可编程控制器系统中。此外，还定义了促进可编程控制器与其他自动化系统组件之间通信的功能。与前一版相比，本版包括以下重大技术变更：a) 包含 UTF-8 字符串及其相关功能；b) 附录 B 包含与 IEC 61131-3:2013 相比新增、删除或已弃用功能的全面列表。 [外文原描述]： IEC 61131-3:2025 specifies the syntax and semantics of programming languages for programmable controllers as defined in IEC 61131-1. This document specifies the syntax and semantics of a unified suite of programming languages for programmable controllers (PCs). This suite consists of the textual language structured text (ST), and the graphical languages, ladder diagram (LD) and function block diagram (FBD). An additional set of graphical and equivalent textual elements named sequential function chart (SFC) is defined for structuring the internal organization of programs and function blocks. Also, configuration elements are defined which support the installation of programmable controller programs into programmable controller systems. In addition, features are defined which facilitate communication among programmable controllers and other components of automated systems. This edition includes the following significant technical changes with respect to the previous edition: a) inclusion of UTF-8 strings and their associated functions; b) Annex B contains a comprehensive list of features that have been added, removed or deprecated in comparison to IEC 61131-3:2013.