在美國(guó)，大多數(shù)參與可編程邏輯控制器（PLC）編程和維護(hù)的人員都傾向于認(rèn)為：梯形圖邏輯是PLC的編程語(yǔ)言。這種理念在很大程度上是由PLC的歷史、以及美國(guó)的工業(yè)控制市場(chǎng)是被以梯形圖邏輯為主要語(yǔ)言的品牌統(tǒng)治所造成的。TRICONEX 3805E

在計(jì)算機(jī)和便攜式計(jì)算機(jī)廣泛應(yīng)用于PLC編程之前，經(jīng)常使用手持式編程器將程序輸入到PLC中。在此之前，通常需要繪制用于不同指令的電氣圖。這就像在PLC出現(xiàn)之前，如何連接原始繼電器邏輯一樣。在手持設(shè)備上，有時(shí)會(huì)用符號(hào)表示不同指令，但是在圖形設(shè)計(jì)的背后，是基于文本的語(yǔ)言。

1994年，電工委員會(huì)（IEC）制定了一個(gè)可用于定義和規(guī)范PLC編程系統(tǒng)的標(biāo)準(zhǔn)IEC61131-3。除了形式化定義諸如計(jì)時(shí)器和計(jì)數(shù)器之類的指令外，該標(biāo)準(zhǔn)還定義了5種編程語(yǔ)言。

In the United States, most people who participate in the programming and maintenance of programmable logic controller (PLC) tend to think that ladder logic is the programming language of PLC. This concept is largely caused by the history of PLC and the fact that the industrial control market in the United States is dominated by the brand with ladder logic as the main language. TRICONEX 3805E
Before computers and portable computers were widely used in PLC programming, hand-held programmers were often used to input programs into PLC. Before that, it is usually necessary to draw electrical diagrams for different instructions. This is like how to connect the original relay logic before the emergence of PLC. On handheld devices, symbols are sometimes used to represent different instructions, but behind the graphic design, there is a text-based language.
In 1994, the Electrotechnical Commission (IEC) formulated a standard IEC61131-3 that can be used to define and standardize PLC programming systems. In addition to formally defining instructions such as timers and counters, the standard also defines five programming languages.