【正文】 制器中發(fā)現(xiàn)很多日立和富士微控制器，在歐洲的控制器中發(fā)現(xiàn)西門子的微控制器以及在美國制造的控制器中發(fā)現(xiàn)摩托羅拉的控制器。但是，經(jīng)過一些年的改進， PLC 控制器的制造商增加了許多特性和改進。 PLC 是通過連續(xù)掃描一個程序來工作的。 該電源一般不用于啟動外部輸入或輸出。這將加快由于損壞零件而引起的任何問題的修理速度。一旦系統(tǒng)修改結(jié)束，將正確的程序重新讀入PLC 控制器也是非常重要的。一個輸入的實際狀態(tài)存儲狀態(tài)存儲在專用存儲器位上，為 “1”或者 “0”。 PLC 使用系統(tǒng)存儲器（現(xiàn)在大部分采用閃存技術了）用于過程控制系統(tǒng)。固定式 PLC 包括 CPU板、I/O 板、顯示面板、內(nèi)存塊、電源等，這些元素組合成一個不可拆卸的整體。采取日本歐姆龍 C200HE 為例，主線模板框架類型結(jié)構、 裸骨 （ CPU 女板） 上的與 CPU 模板加載、 加載其他職位與 I/O 模板 ；如果 I/O 模板很多的時間，可能 I/O 的 CPU 女板后連接的 I/O 擴展電纜擴大女板，上面 ； 在安裝 I/O 模板另一種方法是提供遠程 I/O 從站等。 PLC 的市場潛力是巨大的不僅是在我們的國家，即使在行業(yè)調(diào)查 還制定了以指示，機械產(chǎn)品比例占 42%，必要的 PLC 整合日本使用繼電器、 接觸器控制仍有 24%。在許多年生產(chǎn)實踐中，逐步形成了 PLC 區(qū)議會和 IPC 三腳架的潛力，如表 1，設置，但也有其它返回單個路由智力類型監(jiān)管機構等，以占市場的一定百分比。s micro, slightly, center, is big, giant many kinds of PLC. Divides according to the I/O points, may divide into: Miniature PLC: 32 I/O Small PLC: 256 I/O Medium PLC: 1,024 I/O Largescale PLC: 4,096 I/O Giant PLC: 8,195 I/O In recent years had the single plane to support 300 return routes and above 65,000 I/O largescale system correspondence medium PLC, used 16 ~32 position CPU, micro, small PLC originally used 8 CPU, now according to aspect and so on munication requests, some also changed to 16 ~32 position CPU. Because I/O 64 below PLC sales volume occupies entire PLC 47%, 64 ~256 accounts for 31%, equals the position entire PLC sales volume 78%, therefore to micro, small PLC should study. PLC hardware The PLC controller itself hardware uses the building block system structure, various factories product structure is mostly the same except for minor differences. Take Japanese ohm dragon C200HE as an example, for the main line template frame type structure, the bare bone (the CPU female board) on is loaded with the CPU template, other positions are loaded with the I/O template。無 錫 職 業(yè) 技 術 學 院 畢業(yè)設計說明書（英文翻譯） 1 英 文 PLC development and market conditions PLC development history Programmable Logic Controller’s English name is Programmable Controller。s intermediate stages, is PLC develops the quickest time, the yearly rate continuously maintenance is 30~40%. As a result of the PLC machine relation processing simulation ability and the work aspect function progress, has occupied a part of DCS market (process control) and has gradually monopolized profession and so on sewage treatment, but as a result of industry PC (IPC) the appearance, specially in recent years the field bus technology development, IPC and FCS have also occupied a part of PLC market, therefore the recent years PLC rate of rise, always saying was gradually slow. At present the world has more than 200 factories to produce more than 300 varieties PLC product, main application in automobile (23%), grain processing (%), chemistry/drugs manufacture (%), metal/mine (%), paper pulp/papermaking (%) and so on profession . PLC market conditions Domestic PLC production factory approximately 30, but has not formed quite has the scale the productivity and the famous brand goods, but also some part is by imitates, the document received assembly or pastes the sign the way production, therefore may say PLC has not formed the manufacture industry in our country. As the principle, the technology and the craft do not have the most advanced technique difficulty the product, so long as diligently, is can form the manufacture industry. 無 錫 職 業(yè) 技 術 學 院 畢業(yè)設計說明書（英文翻譯） 2 In the PLC application aspect, our country is very active, in recent years every year approximately newly invested 100,000 to wrap the PLC product, the year sales volume 3 billion Yuan, and the application profession very is also broad. But pares with other countries, in machinefinishing and production line aspect application, but also needs to enlarge the investment. The PLC market potential is huge, not only in our country, even if also has the investigation in industry developed Japan to indicate, the PLC necessary integration of machinery product proportion accounts for 42%, used the relay, the contact device control still has 24%. Therefore, needs to apply PLC the situation very to be also many, in our country was so. Looked from the technical innovation angle that, the our country large and middle scale enterprises also must vigorously develop CIMS (puter integration manufacture system), must form the FMS flexibility manufacture system in the mechanical factory, PLC is a foundation, therefore the PLC market is broad. PLC has reliable, the price small advantage, the function stably plete, the application nimble is convenient, the operation maintenance convenient merit, this is it can lasting hold the market the basic reason, under us elaborated with emphasis several questions, and study its development tendency. 3 PLC hardware and software PLC classification PLC already formed in the 9039。結(jié)果這些控件和監(jiān)視請求，因此 PLC 開發(fā)替代繼電器線和順序控制進行主要產(chǎn)品。但相比之下，在其他國家，在機械加工和生產(chǎn)方面的應用，但也需要擴大投資。 PLC 硬件 PLC 控制器本身硬件使用構建基塊的體系結(jié)構，各種工廠產(chǎn)品結(jié)構大多是相同大同小異。 從結(jié)構上分， PLC 分為固定式和組合式（模塊式）兩種。 CPU 速度和內(nèi)存容量是 PLC 的重要參數(shù)，它們決定著 PLC 的工作速度， IO 數(shù)量及軟件容量等，因此限制著控制規(guī)模。一部分存儲器用來存儲輸入和輸出狀態(tài)。這對于工業(yè)企業(yè)來說是非常重要的。注釋和標記甚至還可以準確地引用零件號，如果需要更換零件的話。不同的模塊使用不同的電流量。幾乎所有需要電氣控制的地方都需要 PLC。當他們首次出現(xiàn)的時候，還不很適合復雜的控制，例如溫度、位置、壓力，等等。從前，它是 8 位的控制器，例如 8051，現(xiàn)在它們是 16 位或者 32 位微控制器?？觳列痛鎯ζ鳎?FLASH memory）的內(nèi)容只有在改變用戶程序的時候可以被改變。另外一部分存儲器用來存儲用戶程序中的變量的內(nèi)容。這有助于避免車間發(fā)生危險情況（一些汽車制造商已經(jīng)建立了通信網(wǎng)絡，可以定期