0228-膜片式離合器的設(shè)計(jì)【全套12張CAD圖】,全套12張CAD圖,膜片,離合器,設(shè)計(jì),全套,12,十二,cad 外文翻譯資料 PLC在冰蓄冷中央空調(diào)系統(tǒng)控制中的應(yīng)用 1 引言 在PLC被開(kāi)發(fā)出來(lái)的三十年里，它經(jīng)過(guò)不斷地發(fā)展，已經(jīng)能結(jié)合模擬I/O，網(wǎng)絡(luò)通信以及采用新的編程標(biāo)準(zhǔn)如IEC 61131-3。然而，工程師們只需利用數(shù)字I/O和少量的模擬I/O數(shù)以及簡(jiǎn)單的編程技巧就可開(kāi)發(fā)出80%的工業(yè)應(yīng)用. PLC已經(jīng)廣泛的應(yīng)用在所有的工業(yè)部門(mén)。據(jù)“美國(guó)市場(chǎng)信息”的世界PLC以及軟件市場(chǎng)報(bào)告稱(chēng)，1995年全球PLC及其軟件的市場(chǎng)經(jīng)濟(jì)規(guī)模約50億美元[5]。隨著電子技術(shù)和計(jì)算機(jī)技術(shù)的發(fā)展，PLC的功能得到大大的增強(qiáng) 由于采用傳統(tǒng)的工具可以解決80%的工業(yè)應(yīng)用，這樣就強(qiáng)烈地需要有低成本簡(jiǎn)單的PLC；從而促進(jìn)了低成本微型PLC的增長(zhǎng)，它帶有用梯形邏輯編程的數(shù)字I/O。然而，這也在控制技術(shù)上造成了不連續(xù)性，一方面80%的應(yīng)用需要使用簡(jiǎn)單的低成本控制器，而另一方面其它的20%應(yīng)用則超出了傳統(tǒng)控制系統(tǒng)所能提供的功能。工程師在開(kāi)發(fā)這些20%的應(yīng)用需要有更高的循環(huán)速率，高級(jí)控制算法，更多模擬功能以及能更好地和企業(yè)網(wǎng)絡(luò)集成。 在八十和九十年代，那些要開(kāi)發(fā)“20%應(yīng)用”的工程師們已考慮在工業(yè)控制中使用PC。PC所提供的軟件功能可以執(zhí)行高級(jí)任務(wù)，提供豐富的圖形化編程和用戶(hù)環(huán)境，并且PC的COTS部件使控制工程師能把不斷發(fā)展的技術(shù)用于其它應(yīng)用。這些技術(shù)包括浮點(diǎn)處理器；高速I(mǎi)/O總線，如PCI和以太網(wǎng)；固定數(shù)據(jù)存儲(chǔ)器；圖形化軟件開(kāi)發(fā)工具。而且PC還能提供無(wú)比的靈活性，高效的軟件以及高級(jí)的低成本硬件。 冰蓄冷中央空調(diào)是將電網(wǎng)夜間谷荷多余電力以冰的冷量形式儲(chǔ)存起來(lái)，在白天用電高峰時(shí)將冰融化提供空調(diào)服務(wù)。由于我國(guó)大部分地區(qū)夜間電價(jià)比白天低得多，所以采用冰儲(chǔ)冷中央空調(diào)能大大減少用戶(hù)的運(yùn)行費(fèi)用。 冰蓄冷中央空調(diào)系統(tǒng)配置的設(shè)備比常規(guī)空調(diào)系統(tǒng)要增加一些，自動(dòng)化程度要求較高，但它能自動(dòng)實(shí)現(xiàn)在滿足建筑物全天空調(diào)要求的條件下將每天所蓄的能量全部用完，最大限度地節(jié)省運(yùn)行費(fèi)用。 具有以下特點(diǎn)： (1)可靠性高。PLC的高可靠性得益于軟、硬件上一系列的抗干擾措施和它特殊的周期循環(huán)掃描工作方式。 (2)具有豐富的I/O接口模塊。PLC針對(duì)不同的工業(yè)現(xiàn)場(chǎng)信號(hào)，有相應(yīng)的I/O模塊與工業(yè)現(xiàn)場(chǎng)的器件或設(shè)備直接連接。另外為了提高操作性能，它還有多種人機(jī)對(duì)話的接口模塊；為了組成工業(yè)局部網(wǎng)絡(luò)，它還有多種通訊聯(lián)網(wǎng)的接口模塊。 (3)采用模塊化結(jié)構(gòu)。為了適應(yīng)各種工業(yè)控制需要，除了單元式的小型PLC以外，絕大多數(shù)PLC均采用模塊化結(jié)構(gòu)。PLC的各個(gè)部件，包括CPU、電源、I/O等均采用模塊化設(shè)計(jì)，由機(jī)架及電纜將各模塊連接起來(lái)，系統(tǒng)的規(guī)模和功能可根據(jù)用戶(hù)的需要自行組合。 (4)編程簡(jiǎn)單易學(xué)。PLC的編程大多采用類(lèi)似于繼電器控制線路的梯形圖形式，對(duì)使用者來(lái)說(shuō)，不需要具備計(jì)算機(jī)的專(zhuān)門(mén)知識(shí)，因此很容易被一般工程技術(shù)人員所理解和掌握。 (5)安裝簡(jiǎn)單，維修方便。PLC不需要專(zhuān)門(mén)的機(jī)房，可以在各種工業(yè)環(huán)境下直接運(yùn)行。各種模塊上均有運(yùn)行和故障指示裝置，便于用戶(hù)了解運(yùn)行情況和查找故障。由于采用模塊化結(jié)構(gòu)，因此一旦某模塊發(fā)生故障，用戶(hù)可以通過(guò)更換模塊的方法，使系統(tǒng)迅速恢復(fù)運(yùn)行 2 控制系統(tǒng)結(jié)構(gòu) 控制系統(tǒng)由下位機(jī)（現(xiàn)場(chǎng)控制工作站）與上位機(jī)（中央管理工作站）組成，下位機(jī)采用可編程序控制器（PLC）與觸摸屏，上位機(jī)采用工業(yè)級(jí)計(jì)算機(jī)與打印機(jī)，系統(tǒng)配置必要的附件如通信設(shè)備接口、網(wǎng)卡、調(diào)制解調(diào)器等，實(shí)現(xiàn)蓄冷系統(tǒng)的參數(shù)化與全自動(dòng)智能化運(yùn)行。 下位機(jī)和觸摸屏在現(xiàn)場(chǎng)可以進(jìn)行系統(tǒng)控制、參數(shù)設(shè)置和數(shù)據(jù)顯示。上位機(jī)進(jìn)行遠(yuǎn)程管理和打印，它包含下位機(jī)和觸摸屏的所有功能。整個(gè)系統(tǒng)以下位機(jī)的工業(yè)級(jí)可編程序控制器為核心，實(shí)現(xiàn)自動(dòng)化控制?？刂圃O(shè)備與器件包括：傳感檢測(cè)元件、電動(dòng)閥、變頻器等。 2.1 下位機(jī)系統(tǒng)（區(qū)域工作站） 2.1.1 TP21觸摸屏 采用TP27彩色觸摸屏作為操作面板，完全取代常規(guī)的開(kāi)關(guān)按鈕、指示燈等器件，使控制柜面談得更整潔。并且，TP27觸摸屏在現(xiàn)場(chǎng)可實(shí)現(xiàn)狀態(tài)顯示、系統(tǒng)設(shè)置、模式選擇、參數(shù)設(shè)置、故障記錄、負(fù)荷記錄、時(shí)間日期、實(shí)時(shí)數(shù)據(jù)顯示、負(fù)荷曲線與報(bào)表統(tǒng)計(jì)等功能，中文操作界面直觀友好。 2.1.2 SIEMENS可編程序控制器 SIMATIC S7-300系列PLC適用于各行各業(yè)、各種場(chǎng)合中的檢測(cè)、監(jiān)測(cè)及控制的自動(dòng)化，其強(qiáng)大功能使其無(wú)論在獨(dú)立運(yùn)行中，或相連成網(wǎng)絡(luò)皆能實(shí)現(xiàn)復(fù)雜控制功能。 該產(chǎn)品具有光電隔離，高電磁兼容；具有很高的工業(yè)適用性，允許的環(huán)境溫度達(dá)60℃；具有很強(qiáng)的抗干擾、抗振動(dòng)與抗沖擊性能，因此在嚴(yán)酷的工作環(huán)境中得到了廣泛的應(yīng)用。 自由通訊口方式也是S7-300型PLC的一個(gè)很有特色的功能，它使S7-300型PLC可以與任何通訊協(xié)議公開(kāi)的其它設(shè)備、控制器進(jìn)行通訊，即S7- 300型PLC可以由用戶(hù)自己定義通訊協(xié)議（例ASCII協(xié)議），波特率為1.5Mbit/s（可調(diào)整）。因此使可通訊的范圍大大增加，使控制系統(tǒng)配置更加靈活、方便。任何具有串行接口的外設(shè)，例如：打印機(jī)或條形碼閱讀器、變頻器、調(diào)制解調(diào)器（Modem）、上位PC機(jī)等都可連接使用。用戶(hù)可通過(guò)編程來(lái)編制通訊協(xié)議、交換數(shù)據(jù)（例如：ASCII碼字符），具有RS232接口的設(shè)備也可用PC/PPI電纜連接起來(lái)進(jìn)行自由通訊方式通訊。 芯片和芯片插座 集成電路是把復(fù)雜電路刻蝕到微小的半導(dǎo)體硅芯片上，故常稱(chēng)做芯片，雙列直插式芯片是用塑料封裝且兩側(cè)帶有間隔為0 ．1英寸的引腳，這些引腳可以插在焊接電路板上或面包板上，封裝內(nèi)部有很細(xì)的線把這些引腳與芯片連接。 1引腳的數(shù)目 引腳是用數(shù)字從一個(gè)缺口或一個(gè)圓孔開(kāi)始逆時(shí)針編號(hào)的，如一個(gè)8腳和一個(gè)14腳的芯片的引腳編號(hào)，對(duì)所有的尺寸芯片都是這樣編號(hào)的。 2芯片插座 芯片焊接時(shí)受熱容易壞掉，它們短短的引腳也不能用散熱片保護(hù)，我們用新片插座來(lái)保護(hù)，嚴(yán)格上應(yīng)該稱(chēng)為雙列直插插座，可以先把插座焊接到電路板上，再把芯片插入插座。 只有當(dāng)需要焊接時(shí)才用芯片插座，用面包板搭電路時(shí)不用插座。 實(shí)際產(chǎn)品的電路中通常不用插座而是把芯片直接焊接在電路板上的，因?yàn)閷?shí)際產(chǎn)品是用機(jī)器焊接的，焊接速度很快（不會(huì)損壞芯片）。你不要這樣做，因?yàn)榭赡軙?huì)損壞芯片，而且在調(diào)試時(shí)要移去芯片，而焊住的芯片要取下且不損壞芯片是很難的。 3從插座上拔出芯片 如果你要取下一個(gè)芯片，你可以用一個(gè)小平口螺絲刀輕輕地把芯片從插座中拔出。仔細(xì)地在兩端把平口螺絲刀插入芯片與插座之間，輕輕地翹起芯片，注意要分別在兩端口起翹，否則會(huì)把引腳弄彎甚至折斷。 5．3雙集型（晶體管）集成電路和MOS集成電路 歷史上，雙集型集成電路曾比MOS集成電路更普及，尤其是對(duì)小規(guī)模集成邏輯電路而言。主要有兩個(gè) ，一個(gè)是最初雙晶體管（即三極管）要比MOS更可靠，其次是三極管速度比MOS管快。但隨著MOS管的可靠性的改進(jìn)以及集成電路變的越來(lái)月復(fù)雜，使得MOS邏輯電路的體積小及損耗功率小的這兩個(gè)優(yōu)點(diǎn)顯得更重要了，雙極型邏輯電路的使用也減少了，然而雙極型晶體管集成電路技術(shù)在高頻邏輯電路中仍有用。 當(dāng)上位機(jī)脫機(jī)時(shí)，在下位機(jī)控制下，整個(gè)系統(tǒng)能正常運(yùn)行。 2.2 上位機(jī)系統(tǒng)（中央管理工作站） 2.2.1 上位機(jī) 上位機(jī)即圖文控制中心，主要由PC機(jī)和激光打印機(jī)組成，采用SIMATIC WINCC軟件平臺(tái)，采用全中文操作界面，人機(jī)對(duì)話友好。管理人員和操作者，可以通過(guò)觀察PC機(jī)所顯示的各種信息來(lái)了解當(dāng)前和以往整個(gè)冰蓄冷自控系統(tǒng)的運(yùn)行情況和所有參數(shù)，并且通過(guò)鼠標(biāo)進(jìn)行設(shè)備管理和執(zhí)行打印任務(wù)。 2.2.2 WINCC軟件平臺(tái) WINCC軟件在自動(dòng)化領(lǐng)域中可用于所有的操作員控制和監(jiān)控任務(wù)。可將過(guò)程控制中發(fā)生的事件清楚地顯示出來(lái)，可顯示當(dāng)前狀態(tài)并按順序記錄，所記錄的數(shù)據(jù)可以全部顯示或選擇簡(jiǎn)要形式顯示，可連續(xù)或按要求編輯，并可輸出打印報(bào)表和趨勢(shì)圖。 WINCC 能夠在控制過(guò)程中危急情況的初發(fā)階段進(jìn)行報(bào)告，發(fā)出的信號(hào)既可以在屏幕上顯示出來(lái)，也可以用聲音表現(xiàn)出來(lái)。它支持用在線幫助和操作指南來(lái)消除故障。某一 WINCC工作站可專(zhuān)門(mén)用于過(guò)程控制以使那些重要的過(guò)程信息不被屏蔽。軟件輔助操作策略保證過(guò)程不被非法訪問(wèn)，并提供用于工業(yè)環(huán)境中的無(wú)錯(cuò)操作。 WINCC 是MICRSOFT WINDOWS98或WINDOWS NT4.0操作系統(tǒng)下，在PC機(jī)上運(yùn)行的面向?qū)ο蟮囊涣?2位應(yīng)用軟件，通過(guò)OLE和ODBC視窗標(biāo)準(zhǔn)機(jī)制，作為理想的通訊伙伴進(jìn)入WINDOWS世界，因此WINCC可容易地結(jié)合到全公司的數(shù)據(jù)處理系統(tǒng)中。 3 冰蓄冷系統(tǒng)的控制 3.1 控制目的、范圍及主要受控設(shè)備 蓄冷控制系統(tǒng)控制目的：通過(guò)對(duì)制冷主機(jī)、儲(chǔ)冰裝置、板式熱交換器、系統(tǒng)水泵、冷卻塔、系統(tǒng)管路調(diào)節(jié)閥進(jìn)行控制，調(diào)整儲(chǔ)冰系統(tǒng)各應(yīng)用工況的運(yùn)行模式，在最經(jīng)濟(jì)的情況下給末端提供一穩(wěn)定的供水溫度。同時(shí)，提高系統(tǒng)的自動(dòng)化水平，提高系統(tǒng)的管理效率和降低管理勞動(dòng)強(qiáng)度。 控制范圍包括整個(gè)冰蓄冷系統(tǒng)的參數(shù)狀態(tài)顯示、設(shè)備狀態(tài)及控制，主要控制設(shè)備有：雙工況主機(jī)、電動(dòng)閥、冷卻塔、冷卻水泵、蓄冰裝置、初級(jí)乙二醇泵、板式換熱器、次級(jí)乙二醇泵等。 3.2 控制功能 控制功能包括整個(gè)冰蓄冷系統(tǒng)穩(wěn)定、經(jīng)濟(jì)運(yùn)行所需的功能。 3.2.1 工況轉(zhuǎn)換功能 根據(jù)季節(jié)和機(jī)器運(yùn)行情況，自控系統(tǒng)具備以下工況轉(zhuǎn)換功能： a） 雙工況主機(jī)制冰同時(shí)供冷模式；b） 雙工況主機(jī)單獨(dú)制冰模式；c） 主機(jī)與蓄冰裝置聯(lián)合供冷模式；d） 融冰單獨(dú)供冷模式；e） 主機(jī)單獨(dú)供冷模式。 3.2.2 工況的啟停、顯示和故障報(bào)警功能 控制系統(tǒng)按編排的時(shí)間順序，結(jié)合負(fù)荷預(yù)測(cè)軟件，控制制冷主機(jī)及外圍設(shè)備的啟停數(shù)量及監(jiān)視各設(shè)備之工作狀況與運(yùn)行參數(shù)，如： - 制冷主機(jī)啟停、狀態(tài)及故障報(bào)警；-制冷主機(jī)運(yùn)行參數(shù)；-制冷主機(jī)缺水保護(hù)；-制冷主機(jī)供/回水溫度、壓力遙測(cè)和顯示；-冷凍水泵啟停、狀態(tài)及故障報(bào)警；- 乙二醇泵啟停、狀態(tài)及故障報(bào)警；-冷卻水泵啟停、狀態(tài)及故障報(bào)警；-壓差旁通管的壓差測(cè)量與顯示；-冷卻塔風(fēng)機(jī)啟停、狀態(tài)及故障報(bào)警； -冷卻塔供/回水溫度控制與顯示；-供/回水溫度、壓差遙測(cè)控制與顯示；-板式換熱器側(cè)進(jìn)出口溫度控制與顯示；-蓄冰裝置進(jìn)、出口溫度遙測(cè)控制與顯示；-冷凍水回水流量控制與顯示；-電動(dòng)閥開(kāi)關(guān)、調(diào)節(jié)與閥位控制與顯示；-室外溫濕度遙測(cè)控制與顯示；-蓄冰量測(cè)量與顯示；-末端冷負(fù)荷控制。 3.2.3 數(shù)據(jù)的記錄和打印功能 控制系統(tǒng)對(duì)一些需要的監(jiān)測(cè)點(diǎn)進(jìn)行整年趨勢(shì)記錄，控制系統(tǒng)可將整年的負(fù)荷情況（包括每天的最大負(fù)荷和全日總負(fù)荷）和設(shè)備運(yùn)轉(zhuǎn)時(shí)間以表格和圖表記錄下來(lái)，供使用者使用。所有監(jiān)測(cè)點(diǎn)和計(jì)算的數(shù)據(jù)均能自動(dòng)定時(shí)打印。 3.2.4 手動(dòng)/自動(dòng)轉(zhuǎn)換功能 控制系統(tǒng)配置靈活的手動(dòng)/自動(dòng)轉(zhuǎn)換功能。 3.2.5 優(yōu)化控制功能 根據(jù)室外溫度、天氣預(yù)報(bào)、天氣走勢(shì)、歷史記錄等數(shù)據(jù)自動(dòng)選擇主機(jī)優(yōu)先或融冰優(yōu)先。在滿足末端負(fù)荷的前提下，每天使用完儲(chǔ)存的冷量，盡量少地運(yùn)行主機(jī)。充分發(fā)揮冰儲(chǔ)冷系統(tǒng)優(yōu)勢(shì)，節(jié)約運(yùn)行費(fèi)用。 3.2.6 全自動(dòng)運(yùn)行功能 系統(tǒng)可脫離上位機(jī)工作，根據(jù)時(shí)間表自動(dòng)進(jìn)行制冰和控制系統(tǒng)運(yùn)行、工況轉(zhuǎn)換、對(duì)系統(tǒng)故障進(jìn)行自動(dòng)診斷，并向遠(yuǎn)方報(bào)警。觸摸屏顯示系統(tǒng)運(yùn)行狀態(tài)、流程、各節(jié)點(diǎn)參數(shù)、運(yùn)行記錄、報(bào)警記錄等。 3.2.7 節(jié)假日設(shè)定功能 系統(tǒng)可根據(jù)時(shí)間表自動(dòng)運(yùn)行，同時(shí)也可預(yù)先設(shè)置節(jié)假日，控制儲(chǔ)冰量和儲(chǔ)冰時(shí)間，使系統(tǒng)在節(jié)假日時(shí)對(duì)不需要供應(yīng)空調(diào)的場(chǎng)所停止供冷。 3.2.8 下位機(jī)操作功能 下位機(jī)彩色觸摸屏操作界面見(jiàn)圖1. 下位機(jī)操作功能如下： a） 人機(jī)對(duì)話。操作人員可通過(guò)觸摸面板進(jìn)行人機(jī)對(duì)話，操作界面完全中文化，具有提示、幫助、參數(shù)設(shè)置、密匙設(shè)置、故障查詢(xún)、歷史記錄等功能。 b） 系統(tǒng)設(shè)置。包括操作口令設(shè)置、運(yùn)行設(shè)置、運(yùn)行時(shí)間表設(shè)置、記錄溢出處理、自動(dòng)/手動(dòng)/測(cè)試選擇、節(jié)假日設(shè)置、系統(tǒng)參數(shù)設(shè)置（包括各節(jié)點(diǎn)溫度、壓力，各介質(zhì)的流量，儲(chǔ)冰量，制冰速率，融冰速率，閥門(mén)開(kāi)度，末端負(fù)荷等。） c） 故障記錄、運(yùn)行記錄、歷史記錄等。 3.3 遠(yuǎn)程監(jiān)控 控制系統(tǒng)通過(guò)電話線或?qū)拵ЬW(wǎng)，與專(zhuān)家系統(tǒng)連接，對(duì)系統(tǒng)進(jìn)行運(yùn)行監(jiān)控、參數(shù)修改、數(shù)據(jù)采集等，使系統(tǒng)不斷完善和軟件版本升級(jí)，讓用戶(hù)得到更好的服務(wù)。遠(yuǎn)程監(jiān)控的目的是用戶(hù)可以通過(guò)PSTN（公共交換傳輸網(wǎng)）對(duì)冷凍站進(jìn)行異地遠(yuǎn)程監(jiān)控。同時(shí)也可以實(shí)現(xiàn)遠(yuǎn)程調(diào)試、遠(yuǎn)程適時(shí)監(jiān)控和在線維護(hù)等，從而大大減輕工程人員的工作強(qiáng)度，降低工程成本。 3.4 系統(tǒng)擴(kuò)展控制 控制系統(tǒng)設(shè)計(jì)界面友好，PLC和觸摸屏均可擴(kuò)展，內(nèi)容可擴(kuò)展、參數(shù)也可修改，通過(guò)485通訊接口或通信協(xié)議實(shí)現(xiàn)BAS與冰儲(chǔ)冷自控系統(tǒng)一體化，節(jié)約投資、方便管理。系統(tǒng)集中控制，減少了動(dòng)力柜占地面積，又使動(dòng)力柜型號(hào)統(tǒng)一、式樣相同、大小一致。系統(tǒng)擴(kuò)展控制如下： a） 污水泵自動(dòng)控制； b） 風(fēng)、排風(fēng)控制；c） 活水泵穩(wěn)壓控制；d） 防水泵定時(shí)運(yùn)行、檢測(cè)、報(bào)警； e） 淋水泵穩(wěn)壓控制； f） 筑物夜間輪廓照明自動(dòng)控制；g） 低配計(jì)量、開(kāi)關(guān)狀態(tài)檢測(cè)、報(bào)警。 4 結(jié)語(yǔ) 通過(guò)PLC在冰蓄冷空調(diào)系統(tǒng)的推廣運(yùn)用，驗(yàn)證了PLC系統(tǒng)的可靠性特點(diǎn)，保證了系統(tǒng)的安全運(yùn)行和有效節(jié)能，同時(shí)也為樓宇設(shè)備控制系統(tǒng)的控制器選型提供了新的思路。相信在不久的將來(lái)，越來(lái)越多的PLC系統(tǒng)在冰蓄冷空調(diào)系統(tǒng)的運(yùn)用中日趨成熟，在樓宇設(shè)備控制系統(tǒng)中也將會(huì)大顯身手。 7 外文翻譯資料 PLC in the ice storage central air-conditioning system of control 1 Introduction In PLC in 30 years which developed, it passes through develops unceasingly, already could unify simulates I/O, the network corresponds as well as uses new programming standard like IEC 61131-3. However, engineers only must use digital I/O and few simulations I/O number as well as simple programming skill on potential 80% industrial application. PLC has been widely used in all industrial sectors. According to "The United States market information" World PLC and software market report, in 1995 the global software PLC and its economies of scale of about 5 billion US dollars [5]. As electronic technology and the development of computer technology, Because uses traditional the tool to be possible to solve 80% industrial application, like this intensely needs to have low cost simple PLC; Thus promoted the low cost miniature PLC growth, it has the useful trapezoidal logical programming digital I/O. However, this has also created the discontinuity in the control technology, on the one hand 80% application need to use the simple low cost controller, but on the other hand other 20% application then have surpassed the function which the tradition control system can provide. Engineer is developing these 20% application to need to have the higher circulation speed, the senior control algorithm, the more simulations function as well as can well and the enterprise network integration. In 80 and the 90's, these must develop "20% application" engineers had considered uses PC in the industry control. PC provides the software function may carry out the senior task, provides the rich programming and the user environment, and the PC COTS part enables control engineer the technology which develops unceasingly to use in other applications. These technologies including floating point processor; High speed I/O main line, like PCI and ethernet; Fixed data memory; software development kit. Moreover PC also can provide the incomparable flexibility, highly effective software as well as senior low cost hardware. Ice thermal storage air conditioning is the central power grid could be redundant-night ice electricity in the form of cold storage, in the daytime peak hours of electricity to provide air-conditioning services melting ice. As most parts of our country at night than during the day much lower price, using ice cold storage central air-conditioning can greatly reduce user operating costs. Ice storage central air-conditioning system configuration of equipment than conventional air conditioning system to increase some, require a higher degree of automation, but it automatically to meet the requirements of the air-conditioned buildings all day every day under the conditions of the energy he has exhausted all, the biggest limits to save operating costs. the PLC functions are greatly enhanced, with the following characteristics: (1) high reliability. PLC benefited from the high-reliability hardware and software on a series of anti-jamming measures and the cycle of its special scanning methods of work. (2) with rich I / O interface module. PLC for different industrial field signal and the corresponding I / O modules and industrial devices or equipment at the scene of a direct connection. In addition to improving performance, it also has a variety of man-machine dialogue interface modules to the industrial composition of local area networks, it also multiple communications network interface module. (3) modular structure. To meet the needs of various industrial control, in addition to a small PLC unit, the vast majority of PLC are modular structure. PLC various components, including the CPU, power supply, I / O, etc. is modular in design from the rack and cables will connect each module, the system's size and function in accordance with the needs of users of its own portfolio. (4) easy to learn programming. Most of the PLC programming relay control circuit similar to the ladder diagram form, the user, do not have computer expertise, it is easy to general engineering and technical personnel understand and master. (5) Installation is simple and easy maintenance. PLC does not require specialized equipment room in a variety of industrial environments can be directly run. Various modules are run and fault indication devices, user-friendly understanding of the operation and find fault. The modular structure, so any failure of a module, users can replace the module, allowing the system to rapidly resume operation. Second, the characteristics and Application of industrial PC 2 control system The control system consists of the crew (Floor Control Workstation) and PC (central management workstation), with the crew using programmable logic controller (PLC) with the touch screen, PC using industrial-grade computers and printers, system configuration necessary if the annex communications equipment interfaces, network interface cards, modems and so on, to achieve the parameters of the storage system and intelligent automatic operation. Under the crew at the scene and touch-screen systems can control, parameter settings and data. PC remote management and print, it contains the crew and all of the features touch screen. Following the system as a whole crew of industrial programmable logic controller as the core, to achieve automatic control. Control equipment and devices including: detection sensor components, electric valves, converter, etc.. Under the 2.1-Systems (Regional workstations) 2.1.1 TP21 touch screen TP27 used as a color touch-screen operator panel, completely replace conventional button, lights device, the control cabinet interviewed more tidy. Moreover, TP27 touch screen at the scene showed that the state can be realized, system settings, mode selection, parameter setting, fault recording, record load, time-of-day, real-time data, load curve and reporting statistics, and other functions, Chinese intuitive and friendly user interface. 2.1.2 SIEMENS PLC SIMATIC S7-300 Series PLC applied to all walks of life, all kinds of occasions in the detection, monitoring and control automation, its powerful features to both operate independently, or linked to a network able to achieve complex control functions. The product features photoelectric isolation, and high electromagnetic compatibility; high industrial applicability, allowing the ambient temperature of 60 ℃; has a strong anti-jamming and anti-vibration and impact resistance, in the harsh environment of the work has been widely applications. I also means freedom of communications S7-300 PLC, a very unique features, it makes S7-300 PLC with any communication protocol can open other equipment, communications controller, or PLC S7-300 can be defined by the users themselves communications protocols (for example ASCII protocol), baud rate of 1.5 Mbit / s (adjustable). Thus the scope of the communications can be greatly increased, the control system configuration more flexible and convenient. Any serial interface with peripherals, such as: printer or bar code readers, the drive, a modem (Modem), the upper PC can be connected to the machine. Users can program to develop communication protocol to exchange data (such as: ASCII character code), RS232 interface with the equipment available PC / PPI free cable linking communications communication. Chip and Chip Holders lntegrated Circuis are usually called Ics or chips. Thay are complex circuits, which have benn etched onto tiny chips of semiconductor(silicon). The chip is packaged in a plastic holder with pins spaced on a 0.1(2.54mm)grid, which will fit the holes on stipboard. Very fine wires inisde the package link the chip to the pins. 1) Pin numbers The pins are numbered anti-clockwise around the IC(chip) starting near the notch or dot. It shows the numbering for 8-pin and 14-pin Ics, but the principle is the same for all sizes. 2) Chip holders(DIL sockets) ICs(chip)are easily damageded by heat when soldering and their short pins cannot be protected with a heat sink. Instead we use a chip holder, strictly called a DIL socket(DIL=Dual In-Line), which can be safely soldered onto the circuit board. The chip is pushed into the holder when all solding is complete. Chip holders are only nedded when solding so they are not used on breaboards. Commercially produced circuit boards often have chips soldered directly to the board without a chip holder ,usually this is done by a machine which is able to work very quickly .Please donnot attemp to do this yourself because you are likely to destory the chip and it will be different to remove without damage by de-soldering. 3) Removing a chip from its holder 4) If you need to remove a chip it can be gently prized out of the holder with a small flat-blade screwdriver. Carefully lever up each end by inserting the screwdriver blade between the chip and its holder and gently twisting the screwdrive. Take care to statre lifting at both ends before you attempt to remove the chip,otherwise you will bend and possibly break the pins. 5） Bipolar Integrated Circuits MOS Integrated Circuits Historically, bipolar Integrated Circuits used to be much more popular than MOS Integrated Circuits,particularly for small-sace logic Circuits. There were two major reasons for this: first, bipolar-junction transistors originally could be manufactured more reliably than MOS transistors,and second , they were faster, As the reliabitity of MOS transistors improved, and as integrated Circuits became more complex , which made the lower power and small size of MOS logic more important, the popularity of BJT logic decreased, however, BJT technology is still popular for the highest frequency logic circuits. When the PC offline, under the control of the next crew, the entire system can operate normally. PC System 2.2 (central management workstation) PC 2.2.1 PC that is by control centre, mainly by the PC and laser printer components, SIMATIC WINCC software platform used by the entire Chinese user interface, friendly man-machine dialogue. Management and operation, can be observed by PC-display all kinds of information to understand the current and previous controlled the entire ice storage system and the operation of all parameters, and equipment through the mouse print management and the implementation of tasks. 2.2.2 WINCC software platform WINCC software in the field of automation can be used for all operator control and monitoring tasks. Process control can be in the events clearly show, can show that the current state records in accordance with the order, all the recorded data can be displayed or select summary form, or may be required for editing, and output print statements and trends . WINCC able to control the process of the critical early stages of the report, and the signal can be displayed on the screen, and can also use voice demonstrated. It support the use of on-line help and operational guidelines to eliminate fault. WINCC a specialized workstations can be used to control the process so that the important process information is not shielded. - Aided software strategy assurance process is not illegal access, and provide for the industrial environment no wrong in the operation. WINCC is MICRSOFT WINDOWS98 or WINDOWS NT4.0 operating system, running on a PC object-oriented class 32 applications, through Windows OLE and ODBC standard mechanism, as an ideal communications partners to enter WINDOWS world, and therefore can be easily WINCC to integrate a company-wide data processing system. 3 ice storage system control 3.1 control objectives, scope and mainly controlled equipment Storage Control System control purposes: Through the refrigeration host, ice storage devices, plate heat exchanger, the system pumps, cooling towers, piping system regulating valve control, ice storage system adjustment of the status of the operation mode, in the most economical circumstances to the terminal to provide a stable water supply temperature. At the same time, improve the level of automation, improve the management efficiency and reduce labor intensity management. Control of the ice storage system, including the entire state of the parameters, equipment status and control, the main control equipment: duplex status console, electric valves, cooling towers, cooling water pumps, ice storage devices, the primary glycol pump, plate heat exchanger , sub-glycol pumps. 3.2 control Control functions include the ice storage system stability, and economic operation of the required functions. 3.2.1 status of the conversion function Depending on the season and machinery operation, automatic control system with the following conditions conversion functions: A) duplex host ice conditions at the same time cooling mode; b) duplex status of a separate ice-making mainframe model; c) ice-storage devices and host joint cooling mode; d) of ice-melting separate cooling mode; e) for the console alone Cold model. 3.2.2 The status of the start-up and shutdown, display and alarm functions Fault Control system according to the chronological layout with load forecasting software, mainframe and external control refrigeration equipment start-up and shutdown of the surveillance equipment and the number of working conditions and operating parameters, such as: -- Commitment refrigeration console, status and fault alarm - refrigeration mainframe operating parameters - the protection of water cooling host - host for refrigeration / return water temperature, pressure telemetry and display; - Commitment chilled water pumps, status and fault alarm -- glycol pump start-up and shutdown, status and fault alarm - start-up and shutdown cooling pumps, status and fault alarm - bypass pipe pressure measurement and display of pressure - the cooling tower fan Commitment, status and fault alarm; -- For the cooling tower / backwater temperature control and display; - for / return water temperature, pressure telemetry control and display - the import and export side of plate heat exchanger temperature control and display; - ice storage devices import and export control and telemetry temperature display; - chilled water backwater flow control and display; - electric valve switch valve position adjustment and control and display; - outdoor temperature and humidity control and telemetry showed - ice storage and display of measurement - the end of cold load control. 3.2.3 Data recording and printing functions Control system for the monitoring of the needs of the trends point to the entire record, the control system can be the load throughout the year (including the maximum daily load and the load throughout the day) and equipment uptime as tables and charts record for users . All monitoring points and the calculated data can be automatically print regularly. 3.2.4 manual / automatic conversion function Flexible control system configuration manual / automatic conversion function. 3.2.5 optimized control function According to outdoor temperature, weather, weather trends, the historical record, such as mainframe data automatically select the priority or ice-melting priority. In the end load to meet under the premise of the daily use of the cold storage End, as far as possible to run mainframe. Give full play to ice cold storage system advantages, saving operating costs. 3.2.6 automatic functionality From the PC system can work, in accordance with timetable for the automatic ice-making and control system operation, the conversion status of the system for automatic fault diagnosis, and remote alarm. Touch screen display systems operations, processes, each node parameters and operating records, the police records. 3.2.7 holidays function set According to the timetable system can be run automatically, but also to pre-set holidays, and ice control certificates and certificates of ice time, the system does not require the holidays when the supply of cooling air-conditioned places to stop. 3.2.8 operating under the crew function Lower-color touch-screen operator interface Figure 1. Under the crew operating functions are as follows: A) human-computer dialogue. Operation can be carried out through the touch panel interactive, user interface completely in the culture, with tips, help, parameter settings, key settings, fault enquiries, history and so on. B) system settings. Including operation password settings, run setup, operation of the timetable set record overflow processing, automatic / manual / test selection, holiday settings, the system parameter settings (including the junction temperature, pressure, the media flow, reservoir ice, ice rate, the ice-melting rate of valve opening, the terminal load.) C) fault records, running records, historical records. Remote Control 3.3 Control system through the telephone line or broadband network, and expert system connectivity, the system operation control, parameter changes, such as data acquisition, allowing the system to constantly improve and upgrade version of the software, allows users to get a better service. The purpose of the Remote Control users can PSTN (Public Switched Transport Network) on the remote frozen station at the remote monitoring. It may be remote debugging, remote monitoring and timely online maintenance, and so on, thus greatly mitigate the intensity of the work, lower cost of the project. 3.4 control system expansion Control System Design friendly interface, PLC and touch screen can be extended, the content can be extended, parameters can be modified through the 485 communication interface or communications protocol BAS cold storage and ice-controlled system integration, savings investments, facilitate management. Centralized control system, reducing the dynamic counter area, and also allows the dynamic counter models reunification, the same style, same size. Extended control system are as follows: A) sewage pump control; b) wind, ventilation control; c) live pump regulator control; d) regular-pump operation, detection, alarm; e) leaching pump regulator control; f) construction of contour night lighting control ; g) measurement with low switching state detection, alarm. 4 Conclusion PLC through ice storage air-conditioning systems in the promotion of the use of PLC verify the reliability of the system features to ensure the safe operation of the system and effective energy-saving, but also for building control equipment selection system controller provides a new way of thinking. I believe in the near future, a growing number of PLC systems in the ice storage air-conditioning systems in the use of the increasingly mature, in buildings and plant control systems will also play an active role. 10