外文翻译--PLC简介.doc

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1、外文翻译PLC introductionPLC is mainly index word arithmetic operations electrical system programmable logic controller, used to control the production process of mechanical. But a public limited company, the name of the power supply cord vehicles abbreviation. 1 the basic concept, the PLCEarly Programma

2、ble Controller called Programmable Logic Controller (PLC Programmable Controller, questions), it is mainly used to replace relay realize Logic control. With the development of technology, this kind of using microcomputer technology, industrial control device functionality is greatly exceed the logic

3、 control the scope, therefore, today this device called the programmable controller, or PC. But in order to avoid Personal Computer (Personal Computer), so will the abbreviation of confusion as PLC programmable controller, since 1966 PLC us data equipment company (DEC), and the current U.S. research

4、 appears, Japan, Germanys programmable controller quality is fine, the function is strong.1, the basic structure of PLCPLC is essentially a special in industrial control computer, its hardware structure with microcomputer is same, basically, basic structure for:A, powerPLC in the system of power pla

5、ys a very important role. If have no a good and reliable power supply system is not work properly, so the manufacturers of the power of PLC design and manufacturing has paid much attention to. In general ac voltage fluctuation + 10% (+ 15%) range, can not take other measures and will PLC is connecte

6、d directly to the exchange network upB. the central processing unit (CPU)The central processing unit (CPU) is the PLC control central. It according to the function of PLC system program gives receives and storage from programmer type of user programs and data; Check the power, storage, I/O and cordo

7、ned-off timer state, and can the syntax error diagnosis user programs. When PLC is put into operation, it first to scan all the way of receiving site condition and data input device, and separately deposited in the I/O image area, and then from the user program memory read the user program, through

8、detailed explanation according to instructions commands after regulations logic or count operation results into the I/O image area or data register inside. All the user program execution after completion, the I/O image of each output state or output registers transfer data to the corresponding withi

9、n the output device, so circulates run, until it stops running.In order to further improve the reliability of PLC in recent years, for large PLC also adopt double CPU constitute a redundant system, or adopt three CPU voting type system. So, even if a CPU malfunction, the whole system can still norma

10、l operation.C, memoryStorage system software of memory called system program memory.Storage application software of memory called the user program memory.D, input/output interface circuit1, field input interface circuit by optical coupling circuit and the input interface circuit, microcomputer PLC a

11、nd on-the-spot control function is the UI input.2, field output interface circuit output data registers, chosen by electricity road and interrupt request circuit integration, the function of PLC output interface circuit through the site to site perform component of output corresponding control signa

12、ls.E, function moduleSuch as counting, positioning, and other function modules.F, communication moduleAs Ethernet, RS485, profibus-dp communication module, etc.2, PLC principle of workA, scanning technologyWhen PLC investment after the operation, its working process generally divided into three stag

13、es, namely input sampling, the user program execution and output refresh three stages. Complete the above three stages as a scan cycle. In the whole operation period, PLC CPU with certain scanning speed repeating the above three stages.(a) input sampling stage in input sampling stage with scanning m

14、ode in turn, PLC read into all input states and data, and will they deposited in the I/O image area within the relevant units. Input sampling ended, turn to the user program execution and output refresh stage. In these two stages, even if the input status and data changes, I/O image area of state an

15、d the relevant unit data also wont change. Therefore, if the input is the pulse signal, the pulse signal widths must be bigger than a scan cycle, can ensure that in any case, this input all can be read.(2) the user program execution stageIn the user program performance stage, PLC always press down t

16、he order of sequence scanning the user program (ladder diagram). In a scanning each a ladder diagram, and always first scan ladder-diagram left by all the contacts constitute control circuits, and press first left, after the first under the order of the control by contacts constitute the lines logic

17、 operations, and then based on the arithmetic logic result, refresh this logic coil in system RAM storage area in corresponding a state; Or refresh the output coil in the I/O image area in corresponding position state; Or to determine whether to enforce the ladder-diagram prescribed by the special f

18、unction instructions.Namely, the user program execution process, only input points in the I/O image zone state and data will not change, and other output points and soft equipment in the I/O image area or system RAM storage area of state and data is likely to change, and row at top of the ladder dia

19、gram, its program to implement results of row who will the next with these coils or data ladder diagram matters; Instead, row below the ladder diagram, the logic of the coil set state or data only to the next in line to scan cycle it plays a role in the program.In the process of program execution if

20、 used immediately I/O instructions can be direct access I/O points. Namely, use I/O instructions of words, input process image registers value is not update, program directly from the I/O modules, output value will be immediately image registers with renewals this input some difference immediately.(

21、3) output refresh stageWhen scanning the user program ended, PLC came into output refresh stage. During this period, the CPU according to the I/O image area of state and the corresponding data refresh all the output latch circuit, then after output circuit driver corresponding peripherals. At this m

22、oment, is the real output of PLC.Three, PLC internal operation modeAlthough the use of ladder diagram of PLC program is usually used to many relays, timer and counter, but such names on internal not entity with PLC, but these hardware in the memory and program program mode, and doing logic control e

23、diting by output elements are connected by external mechanical devices do entity control. So can greatly decrease the controller required hardware space. In fact PLC executive ladder diagram program mode of operation is will ladder diagram works by first code scanning mode read in the execution of t

24、he CPU control operation. In whole the scanning process includes three steps, input state examination, the program execution, the output state update that is as follows:Step one input states check : PLC first check the input devices connected to each point switch or sensor state (1 or 0 (on or off),

25、 and its status in the memory of the corresponding position write Xn. Step 2 code-execution : will ladder diagram programs perform take into the CPU, if the program execution in operation need input contact state, direct from the memory inquires CPU removed. The operation result is output coil depos

26、it in corresponding position, memory does not react to the output transient Yn. Step 3 output status update : will the output state step 2 update to the PLC output department contact, and back to step 1. Of the three steps called PLC, and completed scanning cycle the time needed for the reaction tim

27、e, called PLC PLC input signal if less than this time reaction time, are misreading of possibility. After the program execution with the next time before the program execution, output and input state will be updated once, so say such works as output input renewable ended the program.4, PLC current m

28、ain brandAmerican AB, ABB, panasonic, Siemens, HuiChuan, mitsubishi, omron, Taiwan), Fuji, schneider, believe the mitsubishi PLC asMitsubishi PLC English name say again: Mitsubishi Power Line Communication, is in dalian Mitsubishi electric production of main products. Mitsubishi PLC in the Chinese m

29、arket common have the following models: FR - FX1N FR - FX1S FR - FX2N FR - FX3U FR - FX2NC FR - A FR - Q5, rhombohedrons PLC products seriesFX1S series: mitsubishi PLC is a kind of collect molding small cellular PLC. And with complete performance and communication function etc extensibility. If cons

30、idering installing space and cost is a kind of ideal choice.Mitsubishi motors FX1N series: is launched powerful auv PLC. Has expanded input/output, analogue control and communication, link function etc extensibility. Is in a widely used in general sequence control mitsubishi PLC.FX2N series: mitsubi

31、shi PLC is the family is the most advanced in FX series. A high-speed processing and extensible large meet the special function module individual needs characteristics, such as factory automation application provides maximum flexibility and control ability.FX3U: mitsubishi electric company recently

32、introduced into is the new third-generation mitsubishi PLC, may be called small supreme products. Basic performance increases, the basic unit output type transistor built-in 3 axis positioning function of independent supreme 100 KHZ, and increased new positioning instruction, thus make the positioni

33、ng control function more powerful, use more convenient.FX1NC FX2NCFX3UC mitsubishi PLC: in kept the original based on the strong function realized the extremely considerable scaled-down I/O type wiring interface reduced wiring costs, and save time.Q series of mitsubishi PLC: mitsubishi machine compa

34、ny launched large-scale PLC, CPU type has the basic CPU, high-performance type CPU, process control CPU, motion control CPU, redundancy CPU, etc. Can meet various complicated control requirements. Mitsubishi motors China business of rapid development, in order to better satisfy the users for mitsubi

35、shi PLC, Q series products high performance and low cost requirements, mitsubishi electric automation promote economic QUTESET type, i.e. a paragraph of mitsubishi PLC to bring 64 points of high-density mixing unit 5 slot Q00JCOUSET; Another kind of bringing the two pieces of 16 point switch input a

36、nd the two pieces of 16 point switching output Q00JCPU - 8 slot S8SET, its performance index Q00J fully compatible with GX - and fully support Developer software, it has excellent ratio.A series of mitsubishi PLC: use the mitsubishi special sequence control chip (MSP), speed/commands comparable with

37、 large mitsubishi PLC; A2ASCPU support 32 PID circuits. And the number of QnASCPU unrestricted and with the loop size of memory capacity change; Program 124K by 8K steps to capacity step, such as the use of memory card, while QnASCPU 2M is extended to the stock in bytes); A variety of special module

38、 can be options, including network, positioning control, high-speed count, the temperature control module.5, mitsubishi PLC main characteristics(1) structure flexibleDo not suffer environmental restrictions, have electricity can form network, but can be flexible expand access port number, make resou

39、rces keep higher utilization, in mobility and wireless local-area network (WLAN in comparable.(2) transmission quality, speed and bandwidth is stableCan very smooth online watch a DVD of the film, and it can be provided for many applications 14Mbps bandwidth platform provides guarantee. HomePlug AV

40、latest powerline standard transmission rate has reached 200Mbps; In order to ensure HomePlug AV adopted, QoS at road access (TDMA) and the carrier of collision detection function with protected reliably against detective multiple access (CSMA) agreement, both union, perfectly transmission flow media

41、.(3) rangeUbiquitous electric network is the advantage of this technology. Although the wireless network can do not break it, but for high-rise building, the necessary to satisfy layont N several AP demand, and also cannot avoid blind face the existence of signal. And power lines is the most fundame

42、ntal of the network, its scale, is any other network and incomparable. Thus, operators can easily put the Internet access service to infiltrate every place has the power of place. This technology once completely into the commercialization phase, will give the popularization of the Internet brings th

43、e enormous development space. End user just need to plug in electric cats, can realize the Internet access, the TV channel, receiving programs or video phone call(4) low costMake full use of the existing low voltage distribution network infrastructure, no wiring, economize resources. No dug trenches

44、 and wear wall make hole, avoids to buildings, public facilities, and the family decoration destruction, while also save manpower. Relative to traditional networking technology, PLC cheaper, short construction period, scalability and manageability stronger. At present domestic has opened the electri

45、c power broadband Internet access, the month where for 50 - general use cost around $80 / month, so that price and many places of ADSL month phase flat.Will5 widely applicablePLC as a power line networking using technology that provides broadband access network last mile solutions, widely used in re

46、sidential area, hotel, office, monitoring security, etc. It is to use power lines as the communication carrier, makes great convenience of PLC in the room, if any, where power sockets immediately without dial-up, can enjoy 4.5 45Mbps high-speed Internet access, come to browse the web, call, and watc

47、h online movies, so as to realize the set data, voice, video, and power in one of the four nets oneness.PLC program encryptionEach application PLC manufacturers will protect their own programs are not others copy, and equipment manufacturers in order to control the use and recycling payment within.

48、In some parameters set program control. Each manufacturer has its own encryption method: mitsubishi PLC decryption the simplest, among them with Siemens S7-200CN encryption the most complex, only removed from chip code-breaking machine.Electric communication technology (PLC)6 and the concept of elec

49、tric communication PLCUsually, we typically have: the way the Internet using telephone line of dial-up, xDSL mode; Through the CABLE TV line CABLE MODEM way, or use twisted-pair CABLE Ethernet way. Now, we again many a more convenient, more economic choice: using wires, this is PLC! PLC English full name is the Power Line Communication, namely the Power lines of Communication. By using the transmission of the electric current carrier, as the communic