基于PLC的飲料灌裝機(jī)控制系統(tǒng)設(shè)計(jì)
基于PLC的飲料灌裝機(jī)控制系統(tǒng)設(shè)計(jì),基于,PLC,飲料,灌裝,控制系統(tǒng),設(shè)計(jì)
摘 要
隨著工業(yè)自動化水平日益提高,眾多工業(yè)企業(yè)均面臨著傳統(tǒng)生產(chǎn)線的改造和重新設(shè)計(jì)問題。PLC(可編程序控制器)是以微處理器為核心的工業(yè)控制裝置,它將傳統(tǒng)的繼電器控制系統(tǒng)與計(jì)算機(jī)技術(shù)結(jié)合在一起,近年來在工業(yè)自動控制、機(jī)電一體化、改造傳統(tǒng)產(chǎn)業(yè)等方面得到普遍應(yīng)用。
作為通用工業(yè)控制計(jì)算機(jī),其實(shí)現(xiàn)了工業(yè)控制領(lǐng)域接線邏輯到存儲邏輯的飛躍,在世界工業(yè)控制中發(fā)揮著越來越重要的作用。在飲料行業(yè),自動化生產(chǎn)線的生產(chǎn)方式是推廣的最普及的一種生產(chǎn)模式,它促使灌裝的速度大幅提升,同時也使得灌裝精度更高,給企業(yè)帶來了不可小覷的生產(chǎn)力。鑒于此,設(shè)計(jì)者利用PLC的功能和特點(diǎn)設(shè)計(jì)出了一款飲料灌裝生產(chǎn)流水線控制系統(tǒng)。 本文所涉及的飲料灌裝自動化生產(chǎn)線采用PLC控制,流量計(jì)計(jì)量,確保了灌裝的速度和精度。
本文詳細(xì)論述了飲料灌裝機(jī)控制系統(tǒng)的設(shè)計(jì)步驟,通過對灌裝機(jī)系統(tǒng)的充分了解,以行業(yè)現(xiàn)狀為出發(fā)點(diǎn),結(jié)合其他行業(yè)自動控制技術(shù)的應(yīng)用情況,提出了基于PLC的飲料灌裝機(jī)控制系統(tǒng)的基本結(jié)構(gòu)。本系統(tǒng)設(shè)計(jì)中完成了飲料灌裝機(jī)控制系統(tǒng)的硬件的配置和軟件方面的設(shè)計(jì),實(shí)現(xiàn)了飲料灌裝機(jī)控制系統(tǒng)的自動化。對勞動生產(chǎn)率的提高,對飲料的質(zhì)量和產(chǎn)量的提高都具有深遠(yuǎn)的意義。利用PLC控制飲料灌裝生產(chǎn)過程,可有效提高灌裝生產(chǎn)效率,并顯著增加控制系統(tǒng)的可靠性和柔性。
關(guān)鍵詞:可編程控制器;自動化;灌裝;生產(chǎn)線
Ⅰ
Abstract
With?the?increasing?level?of?industrial?automation,?many? industrial?enterprises?are?faced?with?the?transformation?of?traditional?production?line?and?re-design?problem.?PLC?(programmable?logic?controller)?is?a?microprocessor?as?the?core?of?industrial?control?devices,?it?will?relay?the?traditional? control?system?combined?with?computer?technology?in?recent?years?in?industrial?automation,?mechanical?and?electrical?integration,?the?transformation? of?traditional?industries?such?as?generally?applied.?
As?a?general-purpose?industrial?control?computer,?the?realization?of?industrial?control?wiring?logical?leap?in?logic?to?storage,?industrial?control ?in?the?world?is?playing?an?increasingly?important?role.?In?beverage?industry,automated?production?line?mode?of?production?is?to?promote?the?most?popular?a?kind?of?production?mode,?it?causes?the?filling?speed?increases,?but?make?the?filling?a?higher?precision,?to?bring?enterprise?cannot?small? gaze?of?productivity.?In?view?of?this,?the?designers?of?the?use?of?PLC?functions?and?features?designed?a?beverage?filling?production?line?control?system.????
This?paper?involves?the?drinks?filling?automation?production?line? adopts?PLC?control,?flow?meter?metering,?insure?the?filling?speed?and?precision.?This?paper?describes?in?detail?the?control?system?of?the?drinksfilling?machine?design?steps,?a?brief?introduction?of?the?drinks?filling?machine?control?system?and?baseon?the?self-industry?and?the?application?of?the?other?trade?on?auto-control?technique,?proposed?the?frame?of?the?control?system?based?on?programmable?logical?controller.?This?design?completes?the?drinks?production?line?hardware?configuration?and?software?design,to?achieve?the?automation?of?the?carbonated?drinks?filling?machine.?Not?only?improve?the?labor?productivity,?but?also?has?far-reaching?significance?of?the?improvement?of?quality?and?yield.?PLC?control?of?the?use?of?beverage?filling?production?process,?which?can?effectively?improve?the?production?efficiency?of?filling,?and?significantly?increase?the?reliability?of?controlsystems?and?flexible.??
Keywords:?Programmable?controller;Automation;Filling;Production?line
Ⅰ
畢業(yè)設(shè)計(jì)(論文)任務(wù)書
填表時間: 2010 年 03月 15 日 (指導(dǎo)教師填表)
學(xué)生姓名
專業(yè)班級
指導(dǎo)教師
課題類型
工程設(shè)計(jì)
題目
基于plc的飲料灌裝機(jī)控制系統(tǒng)設(shè)計(jì)
主要研究
目標(biāo)
(或研
究內(nèi)容)
1. 研究并掌握飲料灌裝系統(tǒng)的功能;
2. 研究并掌握飲料灌裝系統(tǒng)的整體設(shè)計(jì)方案;
3. 熟練掌握PLC控制程序的設(shè)計(jì)方案;
4. 熟悉順控指令的編程方法;
課題要求、主要任務(wù)及數(shù)量(指圖紙規(guī)格、張數(shù),說明書頁數(shù)、論文字?jǐn)?shù)等)
說明書頁數(shù)不低于40頁
圖紙至少4張A1
確定設(shè)計(jì)方案及程序
進(jìn)度計(jì)劃
1—2周 選擇設(shè)計(jì)方向,收集資料,確定設(shè)計(jì)內(nèi)容
3—5周 根據(jù)設(shè)計(jì)內(nèi)容,擬定設(shè)計(jì)方案和措施
6—7 周 繪制設(shè)計(jì)的原理圖和程序圖
8—9周 撰寫論文和設(shè)計(jì)過程
10—11周 校對論文,完善論文,論文答辯
主要參
考文獻(xiàn)
[ l]張文明.全自動液體灌裝機(jī).北京:機(jī)械工業(yè)出版社,2003
[2]張桂香. 馬全廣.電器控制與PLC應(yīng)用.北京:化學(xué)工業(yè)出版社,2004
[3] 廖常初. PLC編程及應(yīng)用. 北京:機(jī)械工業(yè)出版社,2002
[4] 張桂香. 機(jī)電類專業(yè)畢業(yè)設(shè)計(jì)指南. 北京: 機(jī)械工業(yè)出版社,2005
[5]羅芹芝.基于網(wǎng)絡(luò)的啤酒灌裝控制系統(tǒng).北京:機(jī)械工業(yè)出版社, 2001
[6]啤酒灌裝壓蓋機(jī)PLC控制系統(tǒng)設(shè)計(jì).劉永波,趙軍等.本溪冶金高等??茖W(xué)校學(xué)報,2001
指導(dǎo)教師簽字: 教研室主任簽字:
年 月 日
中文翻譯
可編程控制器技術(shù)討論與未來發(fā)展
隨著時代的發(fā)展,當(dāng)今的技術(shù)也日趨完善,競爭愈演愈烈;單靠人工的操作已 不能滿足于目前的制造業(yè)前景,也無法保證更高質(zhì)量的要求和高新技術(shù)企業(yè)的形 象. 人們在生產(chǎn)實(shí)踐中看到,自動化給人們帶來了極大的便利和產(chǎn)品質(zhì)量上的保 證,同時也減輕了人員的勞動強(qiáng)度,減少了人員上的編制.在許多復(fù)雜的生產(chǎn)過程 中難以實(shí)現(xiàn)的目標(biāo)控制,整體優(yōu)化,最佳決策等,熟練的操作工,技術(shù)人員或?qū)?家, 管理者卻能夠容易判斷和操作,可以獲得滿意的效果.人工智能的研究目標(biāo)正 是利用計(jì)算機(jī)來實(shí)現(xiàn), 模擬這些智能行為,通過人腦與計(jì)算機(jī)協(xié)調(diào)工作,以人機(jī)結(jié) 合的模式,為解決十分復(fù)雜的問題尋找最佳的途徑 我們在各種場合看到了繼電器連接的控制,那已經(jīng)是時代的過去,如今的繼 電器只能作為低端的基層控制模塊或者簡單的設(shè)備中使用到; PLC 的出現(xiàn)也成 而 為了劃時代的主題,通過極其穩(wěn)定的硬件穿插靈活的軟件控制,使得自動化走向 了新的高潮. PLC 的最大特點(diǎn)在于:電氣工程師已不再電氣的硬件上花費(fèi)太多的心計(jì),只 要將按鈕開關(guān)或感應(yīng)器的輸入點(diǎn)連接到 PLC 的輸入點(diǎn)上就能解決問題, 通過輸出 點(diǎn)連接接觸器或繼電器來控制大功率的啟動設(shè)備, 而小功率的輸出設(shè)備直接連接 就可以. PLC 的內(nèi)部包含了具有中央處理器的 CPU, 并帶有外部 I/O 口擴(kuò)展的 I/O 接口 地址和存儲器三大塊組成,CPU 的核心是由一個或者多個累加器組成,它們具有 邏輯的數(shù)學(xué)運(yùn)算能力, 并能讀取程序存儲器的內(nèi)容通過計(jì)算后去驅(qū)動相應(yīng)的存儲 器和 I/O 接口;I/O 口將內(nèi)部累加器和外部的輸入和輸出系統(tǒng)連接起來,并將相 關(guān)的數(shù)據(jù)存入程序存儲器或者數(shù)據(jù)存儲器中; 存儲器可以將 I/O 口輸入的數(shù)據(jù)存 入存儲器中,并在工作時調(diào)轉(zhuǎn)到累加器和 I/O 接口上,存儲器分程序存儲器 ROM 和數(shù)據(jù)存儲器 RAM,ROM 可以將數(shù)據(jù)永久的存入存儲器中,而 RAM 只能作為 CPU 計(jì)算時臨時計(jì)算使用的緩沖空間. PLC 的抗干擾是極其優(yōu)秀的,我們根本不用去關(guān)心它的使用壽命和工作場合 的惡劣,這些所有的問題已不再成為我們失敗的主題,而留給我們的是關(guān)心如何 來利用 PLC 的內(nèi)部資源為我們加強(qiáng)設(shè)備的控制能力,使我們的設(shè)備更加的柔性. PLC 的語言并不是我們所想象的匯編語言或 C 語言來進(jìn)行編程,而是采用原 有的繼電器控制的梯形圖,使得電氣工程師在編寫程序時很容易就理解了 PLC 的語言,而且很多的非電氣專業(yè)人士也對 PLC 很快認(rèn)識并深入. 以上僅僅是 PLC 的優(yōu)點(diǎn)之一,這也是人們比較容易理解的一部分,在很多的 設(shè)備中,人們已不再希望看到太多的控制按鈕,它們不但容易損壞而且極易產(chǎn)生 人為的失誤,小的并不是主要的失誤也許你還能夠接受;但過大的甚至是致命的 失誤是我們無法容忍的.新的技術(shù)總是為了給我們帶來更安全和便捷的操作,使 得我們面臨的一大堆問題一掃而光, 你有了解過 HMI 嗎?這里說 HMI 你根本不清 楚它是什么,也沒有興趣了解,換一個中文把它說明為觸摸屏或者人機(jī)界面你就 知道了,它和 PLC 的結(jié)合給了我們更大的空間. HMI 控制不僅僅是減少了控制按鈕,增加控制的靈活性,更主要的它是可順 序性的,而且在能夠改變數(shù)據(jù)輸入和數(shù)據(jù)輸出反饋,在溫度控制曲線的模擬也能 直觀的顯示出來.并且能夠通過編寫功能幫助程序來提供各種力所能及的幫助, 使得操作者減少不必要的失誤.HMI 的廠商目前也越來越多,功能也越來越強(qiáng), 價格也越來越低,使用的面越來越廣.HMI 的前景可以說十分的看好. 在很多場合,單靠單機(jī)的控制是無法保證設(shè)備的順暢運(yùn)行,而通過設(shè)備與設(shè) 備的信息交流達(dá)到我們想要的效果.比如在前包裝和后工序的檢測,我們就要將 包裝的信息反饋到檢測處,而檢測處的信息也要反饋到包裝來.這樣通過信息共 享來使得兩者之間鏈接起來, 形成一個共體, 從而使的兩者間的配合更加的緊密, 在彼此間達(dá)到映影相揮的效果. PLC 的通信已經(jīng)愈來愈體現(xiàn)它的價值,在 PLC 與 PLC 之間的通信,能夠通過 信息的溝通和數(shù)據(jù)的共享來保證設(shè)備之間的相互協(xié)調(diào),已達(dá)到互補(bǔ)的效果.PLC 之間的數(shù)據(jù)轉(zhuǎn)換采用 RS232 接口來傳送數(shù)據(jù),而 RS232 接口只能保證 10 米的傳 輸距離,如果在 1000 米的距離內(nèi)我們可以通過 RS485 來進(jìn)行通信,更長的距離 只能通過 MODEL 來進(jìn)行傳輸. PLC 的數(shù)據(jù)傳送只是將內(nèi)部的數(shù)據(jù)傳送到對方的一塊連續(xù)的地址中,我們把 它稱為一個表,對方的 PLC 通過讀取表中的數(shù)據(jù)來進(jìn)行操作.如果表中的數(shù)據(jù)是 一個一般設(shè)置的數(shù)據(jù)的話,那只是一般的數(shù)據(jù)傳送,比如今天的油價上升了,我 要把油價的價格傳送到所有的輸油機(jī)上,那就是數(shù)據(jù)的共享;而當(dāng)表中的數(shù)據(jù)是 一段控制 PLC 的指令程序,那就很有難度了,比如你要控制一臺機(jī)器人來按你想 象的動作工作,你會給它編制一段程序并以數(shù)據(jù)的形式發(fā)送過去. 信息輸送的形式有單工位,半雙工位和全雙工位的分別.單工位的意義也就 是說兩者之間,一個只能發(fā)送,而一個只能接收,比如一個特務(wù)他只能接收上司 的指示,而無法給上司回復(fù);半雙工位也就是兩個能都能發(fā)送和接受數(shù)據(jù),但不 能同時發(fā)送和接受,比如你打電話時是不能接電話,對方也一樣;而全雙工位是 兩者之間都能發(fā)送和接受數(shù)據(jù), 并可同時發(fā)送和接受. 像互聯(lián)網(wǎng)就是典型的例子. 信息輸送的過程也有同步和異步之分:同步的意義在于發(fā)送數(shù)據(jù)時數(shù)據(jù)線和 時鐘線是同步的,也就是數(shù)據(jù)信號和時鐘信號同時由 CPU 進(jìn)行發(fā)送,這需要彼此 都要專門的時鐘信號來進(jìn)行傳送和接送,并且是強(qiáng)制性的,這種方法的特點(diǎn)在于 它的速度極快,但相應(yīng)占用 CPU 的工作時間也相對的要長,同時技術(shù)難度也非常 的大.它的要求在于在一幀的數(shù)據(jù)傳送中不能有一位的誤差,不然的話整個數(shù)據(jù) 將發(fā)生錯誤,這在硬件上是一個比較大的難度.在一些專用的設(shè)備中應(yīng)用的越來 越廣泛,像專用的醫(yī)療設(shè)備,數(shù)字信號設(shè)備等,在比較單一數(shù)據(jù)的傳輸中,它的 效果非常的好. 而異步是應(yīng)用范圍最廣泛的,這得益于它的技術(shù)難度相對要小,同時不需要 配制專門的時鐘信號,它的特點(diǎn)在于,它的數(shù)據(jù)是間隔性的,離散性的發(fā)送和接 受,當(dāng) CPU 太忙的時候可以停頓性去工作,在硬件上也減少了難度,同時數(shù)據(jù)的 丟失相對要少,我們可以通過數(shù)據(jù)的檢測來觀察我們發(fā)送的數(shù)據(jù)是否有錯誤,像 奇偶法,累加法和八位效驗(yàn)法等,都可以用來幫助我們檢測發(fā)送的數(shù)據(jù)是否有錯 誤發(fā)生,通過反饋來進(jìn)行辨別. 信息的傳送口線有串口和并口之分: 通常的 PLC 是 8 位機(jī), 當(dāng)然也有 16 位機(jī). 我們在發(fā)送數(shù)據(jù)的時候可以是一位一位的發(fā)送給對方, 也可以 8 位 8 位的將數(shù)據(jù) 發(fā)送到對方,一位和 8 位區(qū)別也就是我們所說的串口發(fā)送數(shù)據(jù)和并口發(fā)送數(shù)據(jù). 串口速度比較慢,但只要兩條或者三條口線就能解決問題,并能借用電話線來進(jìn) 行遠(yuǎn)程控制.而并口的傳送速度是極快的,它是串口的 256 倍,在短距離占有優(yōu) 勢,由于是 TTL 電平,一般限于 1 米的范圍,它并不適用于長距離的數(shù)據(jù)傳送, 這樣成本太昂貴了. 很多的情況下我們總喜歡采用串并轉(zhuǎn)換芯片來進(jìn)行傳輸,這種情況下不需要 我們進(jìn)行過于復(fù)雜的寄存器設(shè)置了,而直接通過數(shù)據(jù)傳送指令進(jìn)行數(shù)據(jù)交流,但 在通信中并不是一個十分可行的辦法, 因?yàn)樵诎l(fā)送數(shù)據(jù)的時候?qū)Ψ降?PLC 必須一 直等待你的數(shù)據(jù)輸出,它不能去做其他的工作. 當(dāng)你在看書的時候,你聽到有人敲門,你停下手上的事情,去打開門,并同 敲門者對話,這個時候電話響了,你示意接個電話,在接完電話后,回過頭來同 敲門者繼續(xù)對話, 對話完畢后, 你再繼續(xù)看你的書, 這種情況我們把它稱為中斷, 它具有權(quán)威性,也具有優(yōu)先性,PLC 具備了這樣的功能.它的特點(diǎn)在于我們在設(shè) 備的操作過程中可能會遇到緊急的突發(fā)事件,我們要立刻的停下手上的工作,去 處理更重要的事情, 這種情況是我們經(jīng)常所遇到的, 在去執(zhí)行緊急的任務(wù)時, PLC 總會先保存目前的狀態(tài),比如程序的地址,CPU 的累加器數(shù)據(jù)等,就像我們?nèi)ラ_ 門時要記下我們看的書在第幾頁了或者干脆作個記號, 因?yàn)槲覀兇龝€要繼續(xù)接 著看后面的書.CPU 總是按照我們的意愿去做應(yīng)該做的事情,但你錯誤的給它一 件事情,它也會同樣的去做,這一點(diǎn)我們必須注意. 中斷并不是只有一個,有時會同時存在幾個中斷,中斷具有優(yōu)先的級別,他 們會根據(jù)人的要求去執(zhí)行更高級別的中斷. 這種中斷中的中斷也就形成了中斷嵌 套.當(dāng)然中斷的級別根據(jù)各種 PLC 內(nèi)部 CPU 的資源有關(guān),同時也跟堆棧的容量大 小也有關(guān)系. 中斷的內(nèi)容有很多種,比如外部中斷,通信中的發(fā)送和接受中斷,定時和計(jì) 數(shù)的時鐘中斷,還有 WDT 復(fù)位中斷等,它們豐富了 CPU 在處理各種事務(wù)時響應(yīng)種 類.這樣講也許你并不能完全理解中斷的內(nèi)部結(jié)構(gòu)和操作順序,我們做一個小小 的例子來說明. 每一個設(shè)備總是不會忘記有一個按鈕, 它也是在我們遇到緊急情況時使用的, 那就是急停按鈕.當(dāng)我們遇到人身事故和意外情況時我們只要按下它,機(jī)器立即 停止所有的操作,并等待處理完意外后再恢復(fù)操作.急停按鈕連接 PLC 內(nèi)部 CPU 的內(nèi)部 I/O 接口上,當(dāng)按鈕給 CPU 一個外部觸發(fā)信號時,CPU 對 I/O 進(jìn)行再次檢 測,當(dāng)確認(rèn)有外部觸發(fā)信號時,CPU 保護(hù)現(xiàn)場并將程序計(jì)數(shù)器自動轉(zhuǎn)到相應(yīng)的外 部 I/O 中斷程序中去,當(dāng)外部中斷程序處理完畢,程序計(jì)數(shù)器返回到主程序繼續(xù) 工作.有一點(diǎn)可以說明的是我們一般會把急停按鈕的外部中斷升至最高級別,從 而保證安全. 當(dāng)我們在工作完一個工件時,給 PLC 一個信號,將 PLC 的內(nèi)部計(jì)數(shù)器加 1 來 計(jì)算我們一天的工作量時,一個簡單的計(jì)數(shù)器能解決問題,當(dāng)然它們也能夠在掉 電的情況下保持?jǐn)?shù)據(jù),促使數(shù)據(jù)不丟失,這也是我們所渴望的. PLC 還具有高級計(jì)數(shù)器的功能,當(dāng)我們在接受一些高速的數(shù)據(jù)時,這里所說 的高速是在在微秒級的數(shù)據(jù),比如條碼掃描機(jī)在不斷的掃描數(shù)據(jù),數(shù)據(jù)處理器 DSP 計(jì)算的高速信號等,我們就要采用到高級計(jì)數(shù)器來幫助我們進(jìn)行計(jì)數(shù).它在 PLC 執(zhí)行程序時一旦發(fā)現(xiàn)高級計(jì)數(shù)器對應(yīng)的中斷,就會立即放下手上的工作.經(jīng) 過再次編程的梯形圖程序說明我們在執(zhí)行程序時高級計(jì)數(shù)器會自動的執(zhí)行對應(yīng) 的工作,從而將高級計(jì)數(shù)器的級別升至高一級別. 你也許聽過太多的這個詞:"死機(jī)" ,大致的意思是 CPU 工作量過大,內(nèi)部資 源不足等情況造成程序無法運(yùn)行.PLC 也有類似的情況,在 PLC 內(nèi)部有一個看門 狗 WDT,我們可以設(shè)置 WDT 一個程序運(yùn)行的時間,當(dāng)程序運(yùn)行過程中出現(xiàn)程序跳 轉(zhuǎn)錯誤時或者程序繁忙時,程序的運(yùn)行時間超過 WDT 的設(shè)置時間,CPU 轉(zhuǎn)而 WDT 復(fù)位狀態(tài).程序重新開始運(yùn)行,但對中斷不會進(jìn)行破壞. PLC 的發(fā)展已經(jīng)從單一的模式進(jìn)入了通信的網(wǎng)絡(luò)時代,并同其它的工控網(wǎng)板 和 I/O 卡板輕易的進(jìn)行共享.組態(tài)軟件可以將所有的這些硬件連接起來,通過更 直觀的動畫圖片來進(jìn)行控制,并可以通過互聯(lián)網(wǎng)在異地進(jìn)行控制,像神舟五號的 發(fā)射就是采用這種辦法來使飛船升空. 更高層次的發(fā)展需要我們不斷的努力來取得.PLC 的出現(xiàn)已經(jīng)足足影響了幾代 人, 我們也從上一輩的經(jīng)驗(yàn)中獲取了更多的知識和教訓(xùn), 來不斷的發(fā)展 PLC 技術(shù), 將它推向更高浪潮
外文資料翻譯
PLC technique discussion and future development
Along with the development of the ages, the technique that is nowadays is also gradually perfect, the competition plays more more strong; the operation that list depends the artificial has already can't satisfied with the current manufacturing industry foreground, also can't guarantee the request of the higher quantity and high new the image of the technique business enterprise. The people see in produce practice, automate brought the tremendous convenience and the product quantities for people up of assurance, also eased the personnel's labor strength, reduce the establishment on the personnel. The target control of the hard realization in many complicated production lines, whole and excellent turn, the best decision etc., well-trained operation work, technical personnel or expert, governor but can judge and operate easily, can acquire the satisfied result. The research target of the artificial intelligence makes use of the calculator exactly to carry out, imitate these intelligences behavior, moderating the work through person's brain and calculators, with the mode that person's machine combine, for resolve the very complicated problem to look for the best path We come in sight of the control that links after the electric appliances in various situation, that is already the that time generation past, now of after use in the mold a perhaps simple equipments of grass-roots control that the electric appliances can do for the low level only;And the PLC emergence also became the epoch-making topic, adding the vivid software control through a very and stable hardware, making the automation head for the new high tide. The PLC biggest characteristics lie in: The electrical engineering teacher already no longer electric hardware up too many calculationses of cost, as long as order the importation that the button switch or the importation of the sensors order to link the PLC up can solve problem, pass to output to order the conjunction contact machine or control the start equipments of the big power after the electric appliances, but the exportation equipments direct conjunction of the small power can. PLC internal containment have the CPU of the CPU, and take to have an I/ O for expand of exterior to connect a people's address and saving machine three big pieces to constitute, CPU core is from an or many is tired to add the machine to constitute, mathematics that they have the logic operation ability, and can read the procedure save the contents of the machine to drive the homologous saving machine and I/ Os to connect after pass the calculation; The I/ O add inner part is tired the input and output system of the machine and exterior link, and deposit the related data into the procedure saving machine or data saving machine; The saving machine can deposit the data that the I/ O input in the saving machine, and in work adjusting to become tired to add the machine and I/ Os to connect, saving machine separately saving machine RAM of the procedure saving machine ROM and datas, the ROM can can do deposit of the data permanence in the saving machine, but RAM only for the CPU computes the temporary calculation usage of hour of buffer space. The PLC anti- interference is very and excellent, our root need not concern its service life and the work situation bad, these all problems have already no longer become the topic that we fail, but stay to our is a concern to come to internal resources of make use of the PLC to strengthen the control ability of the equipments for us, make our equipments more gentle. PLC language is not we imagine of edit collected materials the language or language of Cs to carry on weaving the distance, but the trapezoid diagram that the adoption is original after the electric appliances to control, make the electrical engineering teacher while weaving to write the procedure very easy comprehended the PLC language, and a lot of non- electricity professional also very quickly know and go deep into to the PLC. Is PLC one of the advantage above and only, this is also one part that the people comprehend more and easily, in a lot of equipmentses, the people have already no longer hoped to see too many control buttons, they damage not only and easily and produce the artificial error easiest, small is not a main error perhaps you can still accept; But lead even is a fatal error greatly is what we can't is tolerant of. New technique always for bringing more safe and convenient operation for us, make we a lot of problems for face on sweep but light, do you understand the HMI? Says the HMI here you basically not clear what it is, also have no interest understanding, change one inside text explains it into the touch to hold or man-machine interface you knew, it combines with the PLC to our larger space. HMI the control not only only is reduced the control press button, increase the vivid of the control, more main of it is can sequence of, and at can the change data input to output the feedback with data, control in the temperature curve of imitate but also can keep the manifestation of view to come out. And can write the function help procedure through a plait to provide the help of various what lies in one's power, the one who make operate reduces the otiose error. Currently the HMI factory is also more and more, the function is also more and more strong, the price is also more and more low, the noodles of the usage are wide more and more. The HMI foreground can say that think ° to be good very. At a lot of situations, the list is is a smooth movement that can't guarantee the equipments by the control of the single machine, but pass the information exchanges of the equipments and equipments to attain the result that we want. For example fore pack and the examination of the empress work preface, we will arrive wrapping information feedback to examine the place, and examine the information of the place to also want the feedback to packing. Pass the information share thus to make both the chain connect, becoming a total body, the match of your that thus make is more close, at each other attain to reflect the result that mutually flick. The PLC correspondence has already come more more body now its value, at the PLC and correspondence between PLCs, can pass the communication of the information and the share of the datas to guarantee that of the equipments moderates mutually, the result that arrive already to repair with each other. Data conversion the adoption RS232 between PLC connect to come to the transmission data, but the RS232 pick up a people and can guarantee 10 meters only of deliver the distance, if in the distance of 1000 meters we can pass the RS485 to carry on the correspondence, the longer distance can pass the MODEL only to carry on deliver. The PLC data transmission is just to be called a form to it in a piece of and continuous address that the data of the inner part delivers the other party, we, the PLC of the other party passes to read data in the watch to carry on the operation. If the data that data in the watch is a to establish generally, that is just the general data transmission, for example today of oil price rise, I want to deliver the price of the oil price to lose the oil ally on board, that is the share of the data; But take data in the watch for an instruction procedure that controls the PLC, that had the difficulty very much, for example you have to control one pedestal robot to press the action work that you imagine, you will draw up for it the form that a procedure combine with the data sends out to pass by. The form that information transport contain single work, the half a work and the difference of a workses .The meaning of the single work also is to say both, a can send out only, but a can receive only, for example a spy he can receive the designation of the superior only, but can't give the superior reply; A work of half is also 2 and can can send out similar to accept the data, but can't send out and accept at the same time, for example when you make a phone call is to can't answer the phone, the other party also; But whole pair works is both can send out and accept the data, and can send out and accept at the same time. Be like the Internet is a typical example. The process that information transport also has synchronous and different step cent: The data line and the clock lines are synchronous when synchronous meaning lie in sending out the data, is also the data signal and the clock signals to be carry on by the CPU to send out at the same time, this needs to all want the specialized clock signal each other to carry on the transmission and connect to send, and is constrained, the characteristics of this kind of method lies in its speed very quick, but correspond work time of take up the CPU and also want to be long oppositely, at the same time the technique difficulty also very big. Its request lies in can'ting have an error margins in a datas deliver, otherwise the whole piece according to compare the occurrence mistake, this on the hardware is a bigger difficulty. Applied more and more extensive in some appropriative equipmentses, be like the appropriative medical treatment equipments, the numerical signal equipments...etc., in compare the one data deliver, its result is very good. And the different step is an application the most extensive, this receive benefit in it of technique difficulty is opposite and want to be small, at the same time not need to prepare the specialized clock signal, its characteristics to lie in, its data is partition, the long-lost send out and accept, be the CPU is too busy of time can grind to a stop sex to work, also reduced the difficulty on the hardware, the data throw to lose at the same time opposite want to be little, we can pass the examination of the data to observe whether the data that we send out has the mistake or not, be like strange accidentally the method, tired addition and eight efficacies method etc., can use to helps whether the data that we examine to send out have or not the mistake occurrence, pass the feedback to carry on the discriminator. A line of transmission of the information contain a string of and combine the cent of: The usual PLC is 8 machines, certainly also having 16 machines. We can be an at the time of sending out the data a send out to the other party, also can be 88 send out the data to the other party, an and 8 differentiationses are also the as that we say to send out the data and combine sends out the data. A speed is more and slowly, but as long as 2 or three lines can solve problem, and can use the telephone line to carry on the long range control. But combine the oscular transmission speed is very quick of, it is a string of oscular of 25600%, occupy the advantage in the short distance, the in view of the fact TTL electricity is even, being limited by the scope of one meter generally, it combine unwell used for the data transmission of the long pull, thus the cost is too expensive. Under a lot of circumstances we are total to like to adopt the string to combine the conversion chip to carry on deliver, under this kind of circumstance not need us to carry on to depositted the machine to establish too and complicatedly, but carry on the data exchanges through the data transmission instruction directly, but is not a very viable way in the correspondence, because the PLC of the other party must has been wait for your data exportation at the time of sending out the data, it can't do other works. When you are reading the book, you hear someone knock on door, you stop to start up of affair, open the door and combine to continue with the one who knock on door a dialogue, the telephone of this time rang, you signal hint to connect a telephone, after connecting the telephone through, return overdo come together knock on door to have a conversation, after dialogue complete, you continue again to see your book, this kind of circumstance we are called the interruption to it, it has the authority, also having sex of have the initiative, the PLC had such function .Its characteristics lie in us and may meet the urgently abrupt affairs in the operation process of the equipments, we want to stop to start immediately up of work, the whereabouts manages the more important affair, this kind of circumstance is we usually meet of, PLC while carry out urgent mission, total will keep the current appearance first, for example the address of the procedure, CPU of tired add the machine data etc., be like to to stick down which the book that we see is when we open the door the page or simply make a mark, because we treat and would still need to continue immediately after book of see the behind. The CPU always does the affair that should do according to our will, but your mistake of give it an affair, it also would be same to do, this we must notice. The interruption is not only a, sometimes existing jointly with the hour several inside break, break off to have the preferred Class, they will carry out the interruption of the higher Class according to person's request. This kind of breaks off the medium interruption to also became to break off the set. The Class that certainly break off is relevant according to various resources of CPU with internal PLC, also following a heap of capacity size of also relevant fasten. The contents that break off has a lot of kinds, for example the exterior break off, correspondence in of send out and accept the interruption and settle and the clock that count break off, still have the WDT to reset the interruption etc., they enriched the CPU to respond to the category while handle various business. Speak thus perhaps you can't comprehend the internal structure and operation orders of the interruption completely also, we do a very small example to explain. Each equipments always will not forget a button, it also is at we meet the urgent circumstance use of, that is nasty to stop the button. When we meet the Human body trouble and surprised circumstances we as long as press it, the machine stops all operations immediately, and wait for processing the over surprised empress recover the operation again.Nasty stop the internal I/ O of the internal CPU of the button conjunction PLC to connect up, be to press button an exterior to trigger signal for CPU, the CPU carries on to the I/ O to examine again, being to confirm to have the exterior to trigger the signal, CPU protection the spot breaks off procedure counts the machine turn the homologous exterior I/ O automatically in the procedure to go to also, be exterior interruption procedure processing complete, the procedure counts the machine to return the main procedure to continue to work.Have 1:00 can what to explain is we generally would nasty stop the button of exterior break off to rise to the tallest Class, thus guarantee the safety. When we are work a work piece, giving the PLC a signal, counting PLC inner part the machine add 1 to compute us for a day of workload, a count the machine and can solve problem in brief, certainly they also can keep the data under the condition of dropping the electricity, urging the data not to throw to lose, this is also what we hope earnestly. The PLC still has the function th
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