可編程控制器中英文翻譯@外文翻譯@外文文獻(xiàn)翻譯

1、<p><b>　　外文原文：</b></p><p>　　Introduction to PLC</p><p>　　In order to use the advantages of all those controllers and eliminate the difficulties, the programmable logic controlle

2、rs were invented. programmable logic controllers (PLCs), also referred to as programmable controllers, are in the computer family.A PLC was replacement for relay devices. They are programmed using a ladder diagram,which

3、is standard electric wiring diagram. As PLC become more flexible, high-level as well as low-level languages are available to PLC programmers. PLC have the flexi</p><p>　　programmable logic controllers were f

4、irst introduced in 1968 as a substitute for hardwired relay panels. The original intent was to replace a mechanical switching device (relay modules).However,since 1968, the capabilities of the PLC were to replace relay p

5、anels,modern PLC have many more functions. Their use extends from simple process control to manufacturing system controls and monitoring.</p><p>　　They are used for high-speed digital processing, high-speed

6、digital communication, high-level computer-language support, and, of course, for basic control.</p><p>　　PLC vary in size and power. A large PLC can have up to 10000 I/O points and support all the functions

7、discussed earlier. There are expansion slots to accommodate PC and oter communitions decices. For many applications, a small PLC is sufficient. The speed of PLC is constantly improving, even the low-end PLC perform at hi

8、gh speed. One to two microsec / kbyte of memory speed is very common.</p><p>　　Programmable logic controllers Architecture</p><p>　　The basic components in a relay panel circuit and the design o

9、f a relay ladder diagram have been discussed. In the implementation of such a circuit, not only doesthe logic problem have to be thought out, but alse the electrical compatibility and wiring layout have to be considered.

10、 Breadboarding a relay panel circuit is a tedious task; it requires a lot of careful planning and work. The debugging and changing of a circuit is even more difficult. Programmable logic controllers replace most of thi&l

11、t;/p><p>　　Like a general-purpose computer, a programmable controller consists of five major parts; CPU (processor), memory, input/out (I/O), power supply, and peripherals.</p><p>　　Programmable lo

12、gic controllers Functions and Configurations.</p><p>　　1 Basic PLC Operation</p><p>　　PLC consist of input modules or poits, a Central Processing Unit (CPU), and output modules or points. An inp

13、ut accepts a variety of digital oranalog signals from various field devices (sensors) and converts them into a logic signal that can be used by the CPU. The CPU makes decisions and executes control instructions based on

14、program instructions in memory. Output modules convert convert control instructions from the CPU into a digital or analog signal that can be used to control various field d</p><p>　　2 Hard-Wired Control</

15、p><p>　　Prior to PLC many of these control tasks were solved by contactors or relay controls. This is often referred to as hardwired control. Circuit diagrams had to be designed. Electrical components specified

16、 and installed, and wiring lists created. Electricians would then wire the components necessary to perform a specific task. If an error was made the wires had to be reconnected correctly. A change in function or expansio

17、n required wxtensive component changes and rewiring.</p><p>　　3 Advantages of PLC </p><p>　　The same, as well as more complex tasks, can be done with a PLC. Wiring </p><p>　　between

18、 devices and relay cintacts is done in the PLC program. Hard-wiring, though still required to connect field device, is less intensive. Modifying the application and correcting errors are easier to handle. It is easier t

19、o create and chang a program in a PLC than it is to wire and rewire a circuit.</p><p>　　Following are just a few of the advantages of PLC:</p><p>　　·Smaller physical size than hard-wire sol

20、ution.</p><p>　　·Easier and faster to make changes.</p><p>　　·PLC have integrated diagnostics and override dunction.</p><p>　　·Applications can be immediately documen

21、ted.</p><p>　　·Applications can be duplicated faster and less expensively.</p><p>　　4 Siements PLC</p><p>　　Siements makes several PLC product lines in the SIMATIC S7 family. T

22、hey are: S7-200, S7-300, S7-400.</p><p>　　(1) S7-200</p><p>　　The S7-200 is referred to as a micro-PLC because of its small size. The S7-200 has a brick design which means that the power supply

23、and I/O terminal are on-board. The S7-200 can be used on smaller, stand-alone applications such as elevators, car washes, or mixing machines. It can also be used on more complex industrial applications such as bottling a

24、nd packaging machines.</p><p>　　(2) S7-300 and S7-400</p><p>　　The S7-300 and S7-400 PLC are used in more complex applications that support a greater number of I/O poits. Both PLC are modular an

25、d expandable. The power supply and I/O consist of separate modules connected to be the CPU. Choosing either the S7-300 or S7-400 depends on the complexity of the task and possible future expansion. Your Siemens sales rep

26、resentative can provide you with additional information on any of the Siemens PLC.</p><p><b>　　5 CPU</b></p><p>　　CPU is a microprocessor system that contains the system memory and i

27、s the PLC decision-making unit. The CPU monitors the inputs and makes decisions based on instructions held in the program memory. The CPU performs relay, couting, timing, data comparison, and sequential operations.</p

28、><p>　　6 Programming Devices</p><p>　　The program is created in a programming device (PG) and then transferred to the PLC. The program for the S7-200 can be created using a dedicated Siemens SIMATI

29、C S7 programming device, such as a PG 720 or PG 740, if STEP 7 Micro/WIN software is installed.</p><p>　　A personal computer (PC), with STEP 7 Micro/WIN installed, can also be used as a programming device wi

30、th the S7-200.</p><p>　　7 Software</p><p>　　A software program is required in order to tell the PLC what instructions it must follow. Programming software is typically PLC specific. A software p

31、ackage for one PLC ,or one family of PLC ,such as the S7 family, would not be useful on other PLC. The S7-200 uses a Windows-based software program called STEP -7 Micro/WIN32, The PG 720 and PG 740 computer in a similar

32、manner to any other computer software.</p><p>　　8 Connector Cables PPI (Poit-Poit Interface)</p><p>　　Connector cables are required to transfer data from the program the programming device to th

33、e PLC. Communication can only take place when the two device speak the same language or protocol. Communication between programming device and the S7-200 is referred to as PPI protocol. An appropriate cable is required f

34、or a programming device such as a PG 720 or PG 740. The S7-200 uses a 9-pin,D-connector. This is a straight-through serial device that is compatible with Siemens programming devices (MPI p</p><p>　　A special

35、 cable,referred to as a PC/PPI cable, is needed when a personal computer is used as a programming device. This cable allows the serial interface of the PLC to communicate with the RS-232 serial interface of a personal co

36、mputer. DIP switched on the PC/PPI cable are used to select an appropriate speed (bit rate) at which information is passed between the PLC and the computer.</p><p><b>　　譯文：</b></p><p&g

37、t;<b>　　可編程控制器</b></p><p>　　為了利用那些控制器的優(yōu)勢(shì)，消除弊端，可編程邏輯控制器（PLC）應(yīng)運(yùn)而生，可編程邏輯控制器（PLC），也就是可編程控制器，是計(jì)算機(jī)家族的一員。一個(gè)PLC就是能代替整個(gè)繼電器控制裝置，它們用梯形圖（梯形圖是標(biāo)準(zhǔn)的電路圖）。由于PLC的編程靈活性逐漸增強(qiáng)，既可使用高級(jí)語(yǔ)言也可使用低級(jí)語(yǔ)言。PLC不僅具有計(jì)算機(jī)的靈活性，同時(shí)也具有與處理過(guò)程及

38、其他裝置連接的界面標(biāo)準(zhǔn)簡(jiǎn)易的特點(diǎn)。它們被應(yīng)用于商業(yè)和工業(yè)領(lǐng)域，在工業(yè)上，從單一設(shè)備到復(fù)雜的制造設(shè)備都廣泛使用PLC控制。</p><p>　　可編程邏輯控制器（PLC）于1968年被首次使用，用來(lái)替代一個(gè)硬接線的繼電器控制板。最初目的是替代機(jī)械開(kāi)關(guān)裝置（繼電模塊）。然而，自從1968年以來(lái)，PLC的功能逐漸代替了繼電器控制板，現(xiàn)代PLC具有更多的功能。其用途從單一過(guò)程控制延伸到整個(gè)制造系統(tǒng)的控制和監(jiān)控。</

39、p><p>　　可編程控制器也可用在高速數(shù)字處理、高速數(shù)字通信以及高級(jí)計(jì)算機(jī)語(yǔ)言的支持方面，當(dāng)然也可用于基本的過(guò)程控制。</p><p>　　PLC在尺寸和功率上不盡相同，一個(gè)大型PLC可以有高達(dá)10000個(gè)輸入輸出點(diǎn)，具有前面討論過(guò)的所有功能。PLC有連接PC機(jī)和其他通信設(shè)備的擴(kuò)展槽，在很多場(chǎng)合下，一個(gè)小的PLC就足夠了。</p><p><b>　　可編程

40、控制器的構(gòu)造</b></p><p>　　我們已經(jīng)討論了繼電器裝置面板電路中的基本部件和繼電器梯形圖的設(shè)計(jì)。在這樣的電路設(shè)計(jì)過(guò)程中，我們不僅要認(rèn)真思考邏輯問(wèn)題，而且還要對(duì)電氣兼用型和布線加以考慮。設(shè)計(jì)繼電器的面板電路是一項(xiàng)乏味的任務(wù)，它需要周密計(jì)劃和大量的工作。電路的調(diào)試和修改變得容易很多。因?yàn)閷?dǎo)線和運(yùn)動(dòng)的機(jī)械部件（繼電器出頭）幾乎全部被軟件所替代，所以整個(gè)系統(tǒng)更加可靠。</p><

41、;p>　　像通用計(jì)算機(jī)一樣，可編程控制器由以下5個(gè)主要部分組成：CPU(處理器)、內(nèi)存、輸入輸出（I/O）、電源和外設(shè)。</p><p>　　可編程控制器的功能和配置</p><p>　　1 PLC的基本操作</p><p>　　PLC包括輸入模塊或輸入點(diǎn)、一個(gè)中央處理單元（CPU）以及輸出模塊或輸出點(diǎn)。輸入單元可以接受來(lái)自不同現(xiàn)場(chǎng)設(shè)備（傳感器）的各種數(shù)字或模

42、擬信號(hào)，然后將它們轉(zhuǎn)換為CPU可以使用的邏輯信號(hào)。CPU根據(jù)存儲(chǔ)器中的程序指令做出判斷，然后執(zhí)行指令。輸出模塊將來(lái)自CPU的控制指令轉(zhuǎn)換為現(xiàn)場(chǎng)控制的各個(gè)設(shè)備（執(zhí)行機(jī)構(gòu)）所能使用的數(shù)字或邏輯信號(hào)。編程設(shè)備用于輸入期望指令，由這些指令來(lái)決定對(duì)于特定的輸入PLC做什么。操作界面能夠顯示過(guò)程信息及輸入新的控制參數(shù)。連接到PLC輸入端的按鈕,通過(guò)電動(dòng)機(jī)的啟動(dòng)器可以啟動(dòng)和停止與PLC連接電動(dòng)機(jī)。</p><p><b&

43、gt;　　2 硬接線控制</b></p><p>　　使用PLC之前，許多控制人為是通過(guò)接觸器和繼電器來(lái)完成的。這就是經(jīng)常所說(shuō)的硬接線控制。必須先設(shè)計(jì)電路圖，確定元件，并且進(jìn)行安裝以及建立接線表，電工再連接需要執(zhí)行特定任務(wù)的元件。如果接線中有一個(gè)錯(cuò)誤，就必須重新連接來(lái)糾正。如果改變功能或擴(kuò)充系統(tǒng)，元件就需要大量變化，并且線路要重接。</p><p><b>　　3 P

44、LC的優(yōu)勢(shì)</b></p><p>　　同樣或更加復(fù)雜的任務(wù)，可以用PLC來(lái)做。設(shè)備同繼電器出典之間的連接由PLC中的程序完成。硬接線雖然依然需要連接到現(xiàn)場(chǎng)設(shè)備，但這一要求已經(jīng)很少了。修改應(yīng)用軟件或糾正錯(cuò)誤要容易些。在PLC中建立或修改程序比起連接或重新連接電路要容易。</p><p>　　下面列出的知識(shí)PLC的一小部分優(yōu)點(diǎn)：</p><p>　　

45、83;比通過(guò)硬接線方式的物理尺寸小</p><p>　　·修改時(shí)更簡(jiǎn)單且更快速</p><p>　　·PLC有綜合診斷和忽略功能</p><p>　　·應(yīng)用軟件能被立即生成文件</p><p>　　·應(yīng)用程序能夠被更快并且費(fèi)用更低的復(fù)制</p><p><b>　　4

46、西門子PLC</b></p><p>　　西門子制造了幾種屬于SIMATIC S7產(chǎn)品系列的PLC。它們是S7-200，S7-300，S7-400。</p><p><b>　?。?）S7-200</b></p><p>　　S7-200由于尺寸小，被稱為微型PLC。S7-200是塊狀設(shè)計(jì)結(jié)構(gòu)，即它的電源和I/O都在一塊板上。S7-

47、200可以被使用在小型的、獨(dú)立的應(yīng)用設(shè)備中，比如：電梯、汽車沖洗器或攪拌機(jī)。它也能被使用到更復(fù)雜的工業(yè)應(yīng)用中，比如：裝瓶機(jī)和打包機(jī)。</p><p>　　（2）S7-300和 S7-400</p><p>　　S7-300和S7-400型的PLC被使用到更復(fù)雜的應(yīng)用中，它們支持更多數(shù)量的I/O點(diǎn)，這兩種PLC都是模塊化的和可擴(kuò)展的。由分立模塊組成的電源和I/O都與CPU連接。根據(jù)應(yīng)用的復(fù)雜

48、性及以后的擴(kuò)展需要來(lái)選擇S7-300或S7-400。西門子銷售代表可以提供給你任何型號(hào)的西門子PLC的附加信息。</p><p><b>　　5 CPU</b></p><p>　　CPU是包括系統(tǒng)存儲(chǔ)的微處理器系統(tǒng)，是PLC的決策單元。CPU監(jiān)控輸入，并根據(jù)保存在程序存儲(chǔ)器中的指令做出決策。然后CPU執(zhí)行繼電器、計(jì)數(shù)器、數(shù)據(jù)比較和順序操作等功能。</p>

49、<p><b>　　6 編程設(shè)備</b></p><p>　　程序是在一個(gè)編程設(shè)備中建立的，然后被傳送到PLC中，S7-200的程序可以使用專用西門子SIMATIC S7編程設(shè)備來(lái)建立，如已經(jīng)安裝了STEP 7 Micro/WIN 軟件，就可以使用PG720或PG740。</p><p>　　安裝了STEP 7 Micro/WIN軟件的個(gè)人計(jì)算機(jī)也可以用

50、作S7-200的編程設(shè)備。</p><p><b>　　7 軟件</b></p><p>　　必須要有一個(gè)軟件程序告訴PLC應(yīng)付從哪一條指令。編程軟件具有PLC的特點(diǎn)。一個(gè)軟件包針對(duì)一個(gè)PLC或一個(gè)PLC系列，比如S7系列，不能應(yīng)用到其他PLC上。基于Windows平臺(tái)的S7-200的編程軟件稱為STEP 7- Micro/WIN32。PG 720和PG 740使用前

51、必須先安裝Micro/WIN32軟件。在個(gè)人計(jì)算機(jī)上安裝STEP 7 -Micro/WIN32的方法同安裝其他計(jì)算機(jī)軟件的方法類似。</p><p>　　8 連接電纜PPI(點(diǎn)對(duì)點(diǎn)接口)</p><p>　　連接電纜被用來(lái)將編程設(shè)備的數(shù)據(jù)傳送到PLC。只有當(dāng)兩個(gè)設(shè)備使用相同的語(yǔ)言或協(xié)議時(shí)才能夠進(jìn)行通訊。西門子編程設(shè)備同S7-200之間的通訊采用PPI協(xié)議。對(duì)于PG720或PG740的編程設(shè)