PLC中英文资料外文翻译

合集下载

步进电机PLC控制技术中英文对照外文翻译文献

步进电机PLC控制技术中英文对照外文翻译文献中英文对照外文翻译文献(文档含英文原文和中文翻译)The shallow treads into the PLC control technique and development trend of electrical engineering1. Say all:Along with the micro-electronics technique and the calculator technical hair Exhibition, the programmable preface controller has an advance by leaps and bounds of hair Exhibition, its function has already outrun a logic control far and far, in proper order The scope of control, it has an effect to combine with calculator, can enter Go to imitate to control most, have along range correspondence function etc.. Have-The person is called it the modern D industry controls of three pay pillar greatly(namely PLC, robot, CAD/CAM)it a, currently programmable controller BE applied in metallurgy extensively, Mineral industry, machine, light Class D realm, automate for the industry Provided to there is the tool of one dint The PLC controls of tread to open the wreath servo organization into the electrical engineering should Used for combining tool machine to produce an on-line number to control a slippery pedestal to control automatically Make, can the province go to the number of that unit to control system, making that unit The cost of controlling the system lowers.2、What is a stepper motor：Stepper motor is a kind of electrical pulses into angular displacement ofthe implementing agency. Popular little lesson: When the driver receives a step pulse signal, it will drive a stepper motor toset the direction of rotation at a fixed angle (and the step angle). You can control the number of pulses to control the angular displacement, so as to achieve accurate positioning purposes; the same time you can control the pulse frequency to control the motor rotation speed and acceleration, to achieve speed control purposes.What kinds of stepper motor sub-：In three stepper motors: permanent magnet (PM), reactive (VR) and hybrid (HB) permanent magnet stepper usually two-phase, torque, and smaller, step angle of 7.5 degrees or the general 15 degrees; reaction step is generallythree-phase, can achieve high torque output, step angle of 1.5 degrees is generally, but the noise and vibration are large. 80 countries in Europe and America have been eliminated; hybrid stepper is a mix of permanent magnet and reactive advantages. It consists of two phases and the five-phase: two-phase step angle of 1.8 degrees while the general five-phase step angle of 0.72 degrees generally. The most widely used Stepper Motor. What is to keep the torque (HOLDING TORQUE)3、Tread into the basic characteristics of electrical engineering:（1）、tread generally into the accuracy of the electrical engineering for tread into Cape of 3-5% and don't accumulate.（2）、tallest temperatures which enter electrical engineering outward appearance and allow tread and lead into the electrical engineering temperature high can make the magnetism material of electrical engineering back first, cause the dint descend thus is as for lose a step, so the electrical engineering outward appearance allow of the tallest temperature should be decided by small back with electrical engineeringmagnetism material and order; Speak generally, the magnetism material backs to order all above have in 130 C an of even be up to 200C above, so tread completely normal into the electrical engineering outward appearance temperature in 80-90C.（3）、dints which enter electrical engineering would with turn to go up but descend soon，While treading to turn to move into the electrical engineering,electrical engineering each electricity feeling which round a set mutually will become one anti- to electromotive force; The frequency is more high, anti- to electromotive force more big ，big in its function, the electrical engineering enlarges with the frequency(or speed) but mutually the electric current let up, causing the dint descend thus.（4）、can revolve normally when 4 enter electrical engineering low speed, but if high in certain the speed can't start, and the companion have a roar the interjection tread to have a technique parameter into the electrical engineering: empty carry start frequency, then tread into electrical engineering at empty carry under circumstance can start normally of pulse frequency, if the pulse frequency is high in should be worth., The electrical engineering can't start normally, the possible occurrence throws a step or blocks up to turn. Under the situation that there is one load, the start frequency should be much lower if want to make the electrical engineering attain high speed to turn to move, the pulse frequency should have an acceleration process, then start the frequency is lower, then press certain acceleration to rise the high hoped. Tread to show the characteristics of with it into the electric motor, turn ages of manufacturing to develop important use to accompany with in the numeral small together of numeral turn technical of development and tread into the electricalengineering technical exaltation，tread will get an application in more realms into the electrical engineering.4、enter an electrical engineering control system to constitute：Tread is a kind of performance organization that will give or get an electric shock a pulse conversion to move for the Cape into the electrical engineering. When tread to receive to a pulse signal into the actuator, it drives a step to press the direction of enactment to turn to move an angle for fixing to be called "tread to be apart from Cape" into the electrical engineering, it revolves one-step circulate with the fixed angle one step. Can pass control pulse piece to control a Cape to move to attain the purpose of assurance most and thus; Can pass control pulse frequency to control electrical engineering to become dynamic speed and acceleration in the meantime, the purpose attained to adjust thus soon treads into the electrical engineering. Can be the special kind electrical engineering that a kind of control uses, make use of it didn't accumulate error margin accuracy to 100 to divide 100 of characteristics, be suffused with to apply in various open a wreath control PLC which enter electrical engineering technique.5、Stepper motor of the PLC control technology:Make the importation tread to be subjected to a homologous control into total amount and pulse frequency of the importation pulse of electrical engineering. Establish the pulse signal occurrence that a pulse total amount and pulse frequency can control a machine therefore and in control，software; Can make use of PL in fixed time a machine composing for the frequency lower control pulse, the pulse frequency can pass in fixed time machine in fixed time constant control pulse period, the pulse amounts control then can establish a the pulsecounter C10 be when the pulse number attain initial value, count machine C1.The action cuts off pulse back track, making it stop, the servo organization tread into the electrical engineering have no the pulse input then stop operation，servo performance organization fixed position be servo performance organization of when move speed to have higher request, can use PLC high-speed pulse，Different PLC it the frequency of high-speed pulse can reach to 4000-6000Hzses. The PLC is used to produce control pulse, passing PLC plait distance exportation several pulses certainly the control treads to turn Cape into the electrical engineering, programmable controller output's control the pulse enters electrical engineering to switch on electricity sequence to assign by the step homologous of round a set. The PLC controls of tread can go an allotment machine by adoption software wreath into the electrical engineering, the hardware wreath goes allotment machine to adopt the PLC resources that the soft wreath takes up more, Tread especially to round a set to count mutually into the electrical engineering big should consider adoption hardware wreath to go allotment machine well for large production line at 4, although the hardware structure is a little bit a little more complicated, can save an exportation importation of taking up the PLC point, the market has a various appropriation chips to choose to use currently. Tread to enlarge to several ten highest hundred folds into the output's control of the actuator PLC of the electrical engineering power pulse, volt, several Anne arrive several ten several Anne s drive an ability, the exportation of general PLC connects to have to certainly drive an ability, but inside usual transistor flow exportation to connect an ability only for ten several arrive several ten volts, several ten arrive several 100 million Anne but tread to then have several request into theelectrical engineering to the power ten arrive up 100 volts, several Anne arrive several ten Anne s drive an ability so should adopt an actuator to output the pulse carry on enlarging.6、Application features of PLC（1）、High reliability, strong anti-interferenceHigh reliability is the key to performance of electrical control equipment. PLC as the use of modern large scale integrated circuit technology, using the strict production process, the internal circuits to the advanced anti-jamming technology, with high reliability. Constitute a control system using PLC, and the same size compared to relay contactor system, electrical wiring and switch contacts have been reduced to hundreds or even thousands of times, fault also greatly reduced. In addition, PLC hardware failures with self-detection, failure alarm timely information. In the application software, application are also incorporated into the peripheral device fault diagnosis procedure, the system is in addition to PLC circuits and devices other than the access protection fault diagnosis. In this way, the whole system extremely high reliability.（2）、Fully furnished, fully functional, applicabilityPLC to today, has formed a series products of various sizes, can be used for occasions of all sizes of industrial control. In addition to processing other than logic, PLC data, most of computing power has improved, can be used for a variety of digital control in the field. A wide variety of functional units in large numbers, so that penetration to the position of PLC control, temperature control, CNC and other industrial control. Enhanced communication capabilities with PLC and human-machine interface technology, using the PLC control system composed of a variety of very easily.（3）、Easy to learn, well engineering and technical personnel welcome PLC is facing the industrial and mining enterprises in the industrial equipment. It interfaces easily, programming language easily acceptable for engineering and technical personnel. Ladder language, graphic symbols and expressions and relay circuit very close to are not familiar with electronic circuits, computer principles and assembly language do not understand people who engage in industrial control to open the door.（4）、System design, the workload is small, easy maintenance, easy to transformPLC logic with memory logic instead of wiring, greatly reducing the control equipment external wiring, make the control system design and construction of the much shorter period, while routine maintenance is also easier up, even more important is to change the procedures of the same equipment has been changedproduction process possible. This is particularly suitable for many varieties, small batch production situations.7、The development trend of 5 domestic and international electrical engineering: （1）、continue along small scaled direction development turned along with electric motor application the realm open widely and each kind of whole machine is continuously small scaled to turn, the electric motor which requests with its kit have to also more and more small, at 57, the electric motor of 42 machine seat numbers applies many after years, now its machine seat number to 39,35,30,25 directions get down extension.（2 ）、right nesses of electric motors carry on comprehensive design namely turn soon position to spread afeeling machine, decelerate the wheel gear etc. and electric motor essence to synthesize design together, so make it be able to constitute 1 to shut wreath system expediently, as a result have one more superior control function.（3）、to five mutually with three mutually the electric motor direction develop，Be suffused with currently applied of two mutually with four mutually the electric motor, its vibration and voice are bigger, but five mutually with three mutually the electric motor have advantage but in regard to these two kinds of electric motors, five mutually the electric motor drive electric circuit compare. 8、Conclusion:At present, the use of programmable process controller (that is, the PLC technology) can easily realize the control of motor speed and the position of the convenient, c onvenient for a variety of stepper motor operation, t o complete a variety of complex work. It represents the advanced industrial automation revolution; accelerate the realization of the electromechanical integration.浅析步进电机的PLC控制技术与发展趋势1、概述随着微电子技术和计算机技术的发展，可编程序控制器有一了突飞猛进的发展，其功能已远远超出了逻辑控制、顺序控制的范围，它与计算机有一效结合，可进行模拟最控制，具有一远程通信功能等。

PLC-外文文献+翻译

Programmable logic controllerA programmable logic controller (PLC） or programmable controller is a digital computer used for automation of electromechanical processes, such as control of machinery on factory assembly lines，amusement rides，or lighting fixtures。

PLCs are used in many industries and machines. Unlike general—purpose computers，the PLC is designed for multiple inputs and output arrangements, extended temperature ranges，immunity to electrical noise，and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed or non-volatile memory。

A PLC is an example of a real time system since output results must be produced in response to input conditions within a bounded time, otherwise unintended operation will result.1.HistoryThe PLC was invented in response to the needs of the American automotive manufacturing industry。

PLC中英文资料外文翻译

附录外文资料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 pathWe 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 theexportation 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. Newtechnique 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 tostart 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 alloperations 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 that the high class counts the machine, being us while accept some datas of high speed, the high speed that here say is the data of the in all aspects tiny second class, for example the bar code scanner is scanning the data continuously, calculating high-speed signal of the data processor DSP etc., we will adopt the high class to count the machine to help we carry on count. It at the PLC carries out the procedure once discover that the high class counts the machine to should of interruption, will let go of the work on the hand immediately. The trapezoid diagram procedure that passes by to weave the distance again explains the high class for us to carry out procedure to count machine would automatic performance to should of work, thus rise the Class that the high class counts the machine to high one Class.You heard too many this phrases perhaps:" crash", the meaning that is mostly is a workload of CPU to lead greatly, the internal resources shortage etc. the circumstance can't result in procedure circulate. The PLC also has the similar circumstance, there is a watchdog WDT in the inner part of PLC, we can establishtime that a procedure of WDT circulate, being to appear the procedure to jump to turn the mistake in the procedure movement process or the procedure is busy, movement time of the procedure exceeds WDT constitution time, the CPU turn but the WDT reset the appearance. The procedure restarts the movement, but will not carry on the breakage to the interruption.The PLC development has already entered for network ages of correspondence from the mode of the one, and together other works control the net plank and I/ O card planks to carry on the share easily. A state software can pass all se hardwares link, more animation picture of keep the view to carries on the control, and cans pass the Internet to carry on the control in the foreign land, the blast-off that is like the absolute being boat No.5 is to adopt this kind of way to make airship go up the sky.The development of the higher layer needs our continuous effort to obtain.The PLC emergence has already affected a few persons fully, we also obtained more knowledge and precepts from the top one experience of the generation, coming to the continuous development PLC technique, push it toward higher wave tide.摘自《可编程控制器技术讨论与未来发展》中文翻译可编程控制器技术讨论与未来发展随着时代的发展,当今的技术也日趋完善、竞争愈演愈烈;单靠人工的操作已不能满足于目前的制造业前景,也无法保证更高质量的要求和高新技术企业的形象.人们在生产实践中看到,自动化给人们带来了极大的便利和产品质量上的保证,同时也减轻了人员的劳动强度,减少了人员上的编制.在许多复杂的生产过程中难以实现的目标控制、整体优化、最佳决策等,熟练的操作工、技术人员或专家、管理者却能够容易判断和操作,可以获得满意的效果.人工智能的研究目标正是利用计算机来实现、模拟这些智能行为,通过人脑与计算机协调工作,以人机结合的模式,为解决十分复杂的问题寻找最佳的途径我们在各种场合看到了继电器连接的控制，那已经是时代的过去，如今的继电器只能作为低端的基层控制模块或者简单的设备中使用到；而PLC的出现也成为了划时代的主题，通过极其稳定的硬件穿插灵活的软件控制，使得自动化走向了新的高潮。

可编程控制器外文翻译、中英文翻译、外文文献翻译

毕业设计中英文翻译院系专业班级姓名学号指导教师20**年 4 月Programmable Logic Controllers (PLC)1、MotivationProgrammable Logic Controllers (PLC), a computing device invented by Richard E. Morley in 1968, have been widely used in industry including manufacturing systems, transportation systems, chemical process facilities, and many others. At that time, the PLC replaced the hardwired logic with soft-wired logic or so-called relay ladder logic (RLL), a programming language visually resembling the hardwired logic, and reduced thereby the configuration time from 6 months down to 6 days [Moody and Morley, 1999].Although PC based control has started to come into place, PLC based control will remain the technique to which the majority of industrial applications will adhere due to its higher performance, lower price, and superior reliability in harsh environments. Moreover, according to a study on the PLC market of Frost and Sullivan [1995], an increase of the annual sales volume to 15 million PLCs per year with the hardware value of more than 8 billion US dollars has been predicted, though the prices of computing hardware is steadily dropping. The inventor of the PLC, Richard E Morley, fairly considers the PLC market as a 5-billion industry at the present time.Though PLCs are widely used in industrial practice, the programming of PLC based control systems is still very much relying on trial-and-error. Alike software engineering, PLC software design is facing the software dilemma or crisis in a similar way. Morley himself emphasized this aspect most forcefully by indicating [Moody and Morley, 1999, p. 110]:`If houses were built like software projects, a single woodpecker could destroy civilization.”Particularly, practical problems in PLC programming are to eliminate software bugs and to reduce the maintenance costs of old ladder logic programs. Though the hardware costs of PLCs are dropping continuously, reducing the scan time of the ladder logic is still an issue in industry so that low-cost PLCs can be used.In general, the productivity in generating PLC is far behind compared to other domains, for instance, VLSI design, where efficient computer aided design tools are in practice. Existent software engineering methodologies are not necessarily applicable to the PLC basedsoftware design because PLC-programming requires a simultaneous consideration of hardware and software. The software design becomes, thereby, more and more the major cost driver. In many industrial design projects, more than SO0/a of the manpower allocated for the control system design and installation is scheduled for testing and debugging PLC programs [Rockwell, 1999].In addition, current PLC based control systems are not properly designed to support the growing demand for flexibility and reconfigurability of manufacturing systems. A further problem, impelling the need for a systematic design methodology, is the increasing software complexity in large-scale projects.PLCs (programmable logic controllers) are the control hubs for a wide variety of automated systems and processes. They contain multiple inputs and outputs that use transistors and other circuitry to simulate switches and relays to control equipment. They are programmable via software interfaced via standard computer interfaces and proprietary languages and network options.Programmable logic controllers I/O channel specifications include total number of points, number of inputs and outputs, ability to expand, and maximum number of channels. Number of points is the sum of the inputs and the outputs. PLCs may be specified by any possible combination of these values. Expandable units may be stacked or linked together to increase total control capacity. Maximum number of channels refers to the maximum total number of input and output channels in an expanded system. PLC system specifications to consider include scan time, number of instructions, data memory, and program memory. Scan time is the time required by the PLC to check the states of its inputs and outputs. Instructions are standard operations (such as math functions) available to PLC software. Data memory is the capacity for data storage. Program memory is the capacity for control software.Available inputs for programmable logic controllers include DC, AC, analog, thermocouple, RTD, frequency or pulse, transistor, and interrupt inputs. Outputs for PLCs include DC, AC, relay, analog, frequency or pulse, transistor, and triac. Programming options for PLCs include front panel, hand held, and computer.Programmable logic controllers use a variety of software programming languages for control. These include IEC 61131-3, sequential function chart (SFC), function block diagram (FBD), ladder diagram (LD), structured text (ST), instruction list (IL), relay ladder logic (RLL), flow chart, C, and Basic. The IEC 61131-3 programming environment provides support for five languages specified by the global standard: Sequential Function Chart,Function Block Diagram, Ladder Diagram, Structured Text, and Instruction List. This allows for multi-vendor compatibility and multi-language programming. SFC is a graphical language that provides coordination of program sequences, supporting alternative sequence selections and parallel sequences. FBD uses a broad function library to build complex procedures in a graphical format. Standard math and logic functions may be coordinated with customizable communication and interface functions. LD is a graphic language for discrete control and interlocking logic. It is completely compatible with FBD for discrete function control. ST is a text language used for complex mathematical procedures and calculations less well suited to graphical languages. IL is a low-level language similar to assembly code. It is used in relatively simple logic instructions. Relay Ladder Logic (RLL), or ladder diagrams, is the primary programming language for programmable logic controllers (PLCs). Ladder logic programming is a graphical representation of the program designed to look like relay logic. Flow Chart is a graphical language that describes sequential operations in a controller sequence or application. It is used to build modular, reusable function libraries. C is a high level programming language suited to handle the most complex computation, sequential, and data logging tasks. It is typically developed and debugged on a PC. BASIC is a high level language used to handle mathematical, sequential, data capturing and interface functions.Programmable logic controllers can also be specified with a number of computer interface options, network specifications and features. PLC power options, mounting options and environmental operating conditions are all also important to consider.2、ResumeA PLC (programmable Logic Controller) is a device that was invented to replace the necessary sequential relay circuits for control.The PLC works by looking at its input and depending upon their state, turning on/off its outputs. The user enters a program, usually via software or programmer, which gives the desired results.PLC is used in many "real world" applications. If there is industry present, chance are good that there is a PLC present. If you are involved in machining, packing, material handling, automated assembly or countless other industries, you are probably already using them. If you are not, you are wasting money and time. Almost any application that needs some type of electrical control has a need for a PLC.For example, let's assume that when a switch turns on we want to turn a solenoid on for 5second and then turn it off regardless of how long the switch is on for. We can do this with a simple external timer. But what if the process included 10 switches and solenoids? We should need 10 external times. What if the process also needed to count how many times the switch individually turned on? We need a lot of external counters.As you can see the bigger the process the more of a need we have for a PLC. We can simply program the PLC to count its input and turn the solenoids on for the specified time.We will take a look at what is considered to be the "top 20" PLC instructions. It can be safely estimated that with a firm understanding of these instructions one can solve more than 80% of the applications in existence.Of course we will learn more than just these instruction to help you solve almost ALL potential PLC applications.The PLC mainly consists of a CPU, memory areas, and appropriate circuits to receive input/output data. We can actually consider the PLC to be a box full of hundreds or thousands of separate relay, counters, times and data storage locations,Do these counters,timers, etc. really exist? No,they don't "physically" exist but rather they simulated and be considered software counters, timers, etc. . These internal relays are simulated through bit locations in registers.What does each part do? Let me tell you.Input RelaysThese are connected to the outside world.They physically exsit and receive signals from switches,sensors,ect..Typically they are not relays but rather they are transistors.Internal Utility RelaysThese do not receive signals from the outside world nor do they physically exist.they are simulated relays and are what enables a PLC to eliminate external relays.There are also some special relays that are dedicated to performing only one task.Some are always on while some are always off.Some are on only once during power-on and are typically used for initializing data that was stored.CountersThese again do not physically exist. They are simulated counters and they can be programmed to count pulses.Typically these counters can count up,down or both up anddown.Since they are simulated,they are limited in their counting speed.Some manufacturers also include high-speed counters that are hardware based.We think of these as physically existing.Most times these counters can count up,down or up and down.TimersThese also do not physically exist.They come in many varieties and increments.The most common type is an on-delay type.Others include off-delays and both retentive and non-retentive types.Increments vary from 1ms through 1s.Output RelaysThere are connected to the outside world.They physically exist and send on/off signals to solenoids,lights,etc..They can be transistors,relays,or triacs depending upon the model chosen Data StorageTypically there are registers assigned to simply store data.They are usually used as temporary storage for math or data manipulation.They can also typically be used to store data when power is removed form the PLC.Upon power-up they will still have the same contents as before power was moved.Very convenient and necessary!A PLC works by continually scanning a program.We can think of this scan cycle as consisting of 3 important steps.There are typically more than 3 but we can focus on the important parts and not worry about the others,Typically the others are checking the system and updating the current internal counter and timer values,Step 1 is to check input status,First the PLC takes a look at each input to determine if it is on off.In other words,is the sensor connected to the first input on?How about the third...It records this data into its memory to be used during the next step.Step 2 is to execute program.Next the PLC executes your program one instruction at a time.Maybe your program said that if the first input was on then it should turn on the first output.Since it already knows which inputs are on/off from the previous step,it will be able to decide whether the first output should be turned on based on the state of the first input.It will store the execution results for use later during the next step.Step 3 is to update output status.Finally the PLC updates the status the outputs.It updates the outputs based on which inputs were on during the first step and the results executing your program during the second step.Based on the example in step 2 it would now turn on the firstoutput because the first input was on and your program said to turn on the first output when this condition is true.After the third step the PLC goes back to step one repeats the steps continuously.One scan time is defined as the time it takes to execute the 3 steps continuously.One scan time is defined as the time it takes to execute the 3 steps listed above.Thus a practical system is controlled to perform specified operations as desired.3、PLC StatusThe lack of keyboard, and other input-output devices is very noticeable on a PLC. On the front of the PLC there are normally limited status lights. Common lights indicate;power on - this will be on whenever the PLC has powerprogram running - this will often indicate if a program is running, or if no program is runningfault - this will indicate when the PLC has experienced a major hardware or software problemThese lights are normally used for debugging. Limited buttons will also be provided for PLC hardware. The most common will be a run/program switch that will be switched to program when maintenance is being conducted, and back to run when in production. This switch normally requires a key to keep unauthorized personnel from altering the PLC program or stopping execution. A PLC will almost never have an on-off switch or reset button on the front. This needs to be designed into the remainder of the system.The status of the PLC can be detected by ladder logic also. It is common for programs to check to see if they are being executed for the first time, as shown in Figure 1. The ’first scan’ input will be true on the very first time the ladder logic is scanned, but false on every other scan. In this case the address for ’first scan’ in a PLC-5 is ’S2:1/14’. With the logic in the example the first scan will seal on ’light’, until ’clear’ is turned on. So the light will turn on after the PLC has been turned on, but it will turn off and stay off after ’clear’ is turned on. The ’first scan’ bit is also referred to at the ’first pass’ bit.Figure 1 An program that checks for the first scan of the PLC4、Memory TypesThere are a few basic types of computer memory that are in use today.RAM (Random Access Memory) - this memory is fast, but it will lose its contents when power is lost, this is known as volatile memory. Every PLC uses this memory for the central CPU when running the PLC.ROM (Read Only Memory) - this memory is permanent and cannot be erased. It is often used for storing the operating system for the PLC.EPROM (Erasable Programmable Read Only Memory) - this is memory that can be programmed to behave like ROM, but it can be erased with ultraviolet light and reprogrammed.EEPROM (Electronically Erasable Programmable Read Only Memory) – This memory can store programs like ROM. It can be programmed and erased using a voltage, so it is becoming more popular than EPROMs.All PLCs use RAM for the CPU and ROM to store the basic operating system for the PLC. When the power is on the contents of the RAM will be kept, but the issue is what happens when power to the memory is lost. Originally PLC vendors used RAM with a battery so that the memory contents would not be lost if the power was lost. This method is still in use, but is losing favor. EPROMs have also been a popular choice for programming PLCs. The EPROM is programmed out of the PLC, and then placed in the PLC. When the PLC is turned on the ladder logic program on the EPROM is loaded into the PLC and run. This method can be very reliable, but the erasing and programming technique can be time consuming. EEPROM memories are a permanent part of the PLC, and programs can be stored in them like EPROM. Memory costs continue to drop, and newer types (such as flash memory) are becoming available, and these changes will continue to impact PLCs.5、Objective and Significance of the ThesisThe objective of this thesis is to develop a systematic software design methodology for PLC operated automation systems. The design methodology involves high-level description based on state transition models that treat automation control systems as discrete event systems, a stepwise design process, and set of design rules providing guidance and measurements to achieve a successful design. The tangible outcome of this research is to find a way to reduce the uncertainty in managing the control software development process, that is, reducing programming and debugging time and their variation, increasing flexibility of theautomation systems, and enabling software reusability through modularity. The goal is to overcome shortcomings of current programming strategies that are based on the experience of the individual software developer.A systematic approach to designing PLC software can overcome deficiencies in the traditional way of programming manufacturing control systems, and can have wide ramifications in several industrial applications. Automation control systems are modeled by formal languages or, equivalently, by state machines. Formal representations provide a high-level description of the behavior of the system to be controlled. State machines can be analytically evaluated as to whether or not they meet the desired goals. Secondly, a state machine description provides a structured representation to convey the logical requirements and constraints such as detailed safety rules. Thirdly, well-defined control systems design outcomes are conducive to automatic code generation- An ability to produce control software executable on commercial distinct logic controllers can reduce programming lead-time and labor cost. In particular, the thesis is relevant with respect to the following aspect Customer-Driven ManufacturingIn modern manufacturing, systems are characterized by product and process innovation, become customer-driven and thus have to respond quickly to changing system requirements.A major challenge is therefore to provide enabling technologies that can economically reconfigure automation control systems in response to changing needs and new opportunities. Design and operational knowledge can be reused in real-time, therefore, giving a significant competitive edge in industrial practice.Higher Degree of Design Automation and Software QualityStudies have shown that programming methodologies in automation systems have not been able to match rapid increase in use of computing resources. For instance, the programming of PLCs still relies on a conventional programming style with ladder logic diagrams. As a result, the delays and resources in programming are a major stumbling stone for the progress of manufacturing industry. Testing and debugging may consume over 50% of the manpower allocated for the PLC program design. Standards [IEC 60848, 1999; IEC-61131-3, 1993; IEC 61499, 1998; ISO 15745-1, 1999] have been formed to fix and disseminate state-of-the-art design methods, but they normally cannot participate in advancingthe knowledge of efficient program and system design.A systematic approach will increase the level of design automation through reusing existing software components, and will provide methods to make large-scale system design manageable. Likewise, it will improve software quality and reliability and will be relevant to systems high security standards, especially those having hazardous impact on the environment such as airport control, and public railroads.System ComplexityThe software industry is regarded as a performance destructor and complexity generator. Steadily shrinking hardware prices spoils the need for software performance in terms of code optimization and efficiency. The result is that massive and less efficient software code on one hand outpaces the gains in hardware performance on the other hand. Secondly, software proliferates into complexity of unmanageable dimensions; software redesign and maintenance-essential in modern automation systems-becomes nearly impossible. Particularly, PLC programs have evolved from a couple lines of code 25 years ago to thousands of lines of code with a similar number of 1/O points. Increased safety, for instance new policies on fire protection, and the flexibility of modern automation systems add complexity to the program design process. Consequently, the life-cycle cost of software is a permanently growing fraction of the total cost. 80-90% of these costs are going into software maintenance, debugging, adaptation and expansion to meet changing needs [Simmons et al., 1998].Design Theory DevelopmentToday, the primary focus of most design research is based on mechanical or electrical products. One of the by-products of this proposed research is to enhance our fundamental understanding of design theory and methodology by extending it to the field of engineering systems design. A system design theory for large-scale and complex system is not yet fully developed. Particularly, the question of how to simplify a complicated or complex design task has not been tackled in a scientific way. Furthermore, building a bridge between design theory and the latest epistemological outcomes of formal representations in computer sciences and operations research, such as discrete event system modeling, can advance future development in engineering design.Application in Logical Hardware DesignFrom a logical perspective, PLC software design is similar to the hardware design of integrated circuits. Modern VLSI designs are extremely complex with several million parts and a product development time of 3 years [Whitney, 1996]. The design process is normally separated into a component design and a system design stage. At component design stage, single functions are designed and verified. At system design stage, components are aggregated and the whole system behavior and functionality is tested through simulation. In general, a complete verification is impossible. Hence, a systematic approach as exemplified for the PLC program design may impact the logical hardware design.可编程控制器1、前言可编程序的逻辑控制器（PLC），是由Richard E.Morley 于1968年发明的，如今已经被广泛的应用于生产、运输、化学等工业中。

(完整版)PLC英文文献+翻译

自动化专业本科毕业设计英文翻译学院(部)：专业班级：学生姓名：指导教师：年月日Programmable Logic ControllerONE：PLC overviewProgrammable controller is the first in the late 1960s in the United States, then called PLC programmable logic controller (Programmable Logic Controller) is used to replace relays. For the implementation of the logical judgment, timing, sequence number, and other control functions. The concept is presented PLC General Motors Corporation. PLC and the basic design is the computer functional improvements, flexible, generic and other advantages and relay control system simple and easy to operate, such as the advantages of cheap prices combined controller hardware is standard and overall. According to the practical application of target software in order to control the content of the user procedures memory controller, the controller and connecting the accused convenient target.In the mid-1970s, the PLC has been widely used as a central processing unit microprocessor, import export module and the external circuits are used, large-scale integrated circuits even when the Plc is no longer the only logical (IC) judgment functions also have data processing, PID conditioning and data communications functions. International Electro technical Commission (IEC) standards promulgated programmable controller for programmable controller draft made the following definition : programmable controller is a digital electronic computers operating system, specifically for applications in the industrial design environment. It used programmable memory, used to implement logic in their internal storage operations, sequence control, timing, counting and arithmetic operations, such as operating instructions, and through digital and analog input and output, the control of various types of machinery or production processes. Programmable controller and related peripherals, and industrial control systems easily linked to form a whole, to expand its functional design. Programmable controller for the user, is a non-contact equipment, the procedures can be changed to change production processes. The programmable controller has become a powerful tool for factory automation, widely popular replication.Programmable controller is user-oriented industries dedicated control computer, with many distinctive features.First, high reliability, anti-interference capability;Second，programming visual, simple;Third, adaptability good;Fourth functional improvements, strong functional interface. TWO：History of PLCProgrammable Logic Controllers (PLC), a computing device invented by Richard E. Morley in 1968, have been widely used in industry including manufacturing systems, transportation systems, chemical process facilities, and many others. At that time, the PLC replaced the hardwired logic with soft-wired logic or so-called relay ladder logic (RLL), a programming language visually resembling the hardwired logic, and reduced thereby the configuration time from 6 months down to 6 days [Moody and Morley, 1999].Although PC based control has started to come into place, PLC based control will remain the technique to which the majority of industrial applications will adhere due to its higher performance, lower price, and superior reliability in harsh environments. Moreover, according to a study on the PLC market of Frost and Sullivan [1995], an increase of the annual sales volume to 15 million PLC per year with the hardware value of more than 8 billion US dollars has been predicted, though the prices of computing hardware is steadily dropping. The inventor of the PLC, Richard E Morley, fairly considers the PLC market as a 5-billion industry at the present time.Though PLCs are widely used in industrial practice, the programming of PLC based control systems is still very much relying on trial-and-error. Alike software engineering, PLC software design is facing the software dilemma or crisis in a similar way. Morley himself emphasized this aspect most forcefully by indicatingIf houses were built like software projects, a single woodpecker could d estroy civilization.”Particularly, practical problems in PLC programming are to eliminate software bugs and to reduce the maintenance costs of old ladderlogic programs. Though the hardware costs of PLC are dropping continuously, reducing the scan time of the ladder logic is still an issue in industry so that low-cost PLC can be used.In general, the productivity in generating PLC is far behind compared to other domains, for instance, VLSI design, where efficient computer aided design tools are in practice. Existent software engineering methodologies are not necessarily applicable to the PLC based software design because PLC-programming requires a simultaneous consideration of hardware and software. The software design becomes, thereby, more and more the major cost driver. In many industrial design projects, more than of the manpower allocated for the control system design and installation is scheduled for testing and debugging PLC programs.In addition, current PLC based control systems are not properly designed to support the growing demand for flexibility and reconfigurability of manufacturing systems. A further problem, impelling the need for a systematic design methodology, is the increasing software complexity in large-scale projects.The objective of this thesis is to develop a systematic software design methodology for PLC operated automation systems. The design methodology involves high-level description based on state transition models that treat automation control systems as discrete event systems, a stepwise design process, and set of design rules providing guidance and measurements to achieve a successful design. The tangible outcome of this research is to find a way to reduce the uncertainty in managing the control software development process, that is, reducing programming and debugging time and their variation, increasing flexibility of the automation systems, and enabling software reusability through modularity. The goal is to overcome shortcomings of current programming strategies that are based on the experience of the individual software developer. Three：now of PLCFrom the structure is divided into fixed PLC and Module PLC, the two kinds of PLC including CPU board, I/O board, display panel, memory block, power, these elements into a do not remove overall. Module type PLC including CPU module, I/O modules, memory, thepower modules, bottom or a frame, these modules can be according to certain rules combination configuration.In the user view, a detailed analysis of the CPU's internal unnecessary, but working mechanism of every part of the circuit. The CPU control works, by it reads CPU instruction, interprets the instruction and executes instructions. But the pace of work by shock signal control.Unit work under the controller command used in a digital or logic operations.In computing and storage register of computation result, it is also among the controller command and work. CPU speed and memory capacity is the important parameters fot PLC . its determines the PLC speed of work, IO PLC number and software capacity, so limits to control size.Central Processing Unit (CPU) is the brain of a PLC controller. CPU itself is usually one of the microcontrollers. Aforetime these were 8-bit microcontrollers such as 8051, and now these are 16-and 32-bit microcontrollers. Unspoken rule is that you’ll find mostly Hitachi and Fujicu microcontrollers in PLC controllers by Japanese makers, Siemens in European controllers, and Motorola microcontrollers in American ones. CPU also takes care of communication, interconnectedness among other parts of PLC controllers, program execution, memory operation, overseeing input and setting up of an output.System memory (today mostly implemented in FLASH technology) is used by a PLC for a process control system. Aside form. this operating system it also contains a user program translated foram ladder diagram to a binary form. FLASH memory contents can be changed only in case where user program is being changed. PLC controllers were used earlier instead of PLASH memory and have had EPROM memory instead of FLASH memory which had to be erased with UV lamp and programmed on programmers. With the use of FLASH technology this process was greatly shortened. Reprogramming a program memory is done through a serial cable in a program for application development.User memory is divided into blocks having special functions. Some parts of a memory are used for storing input and output status. The real status of an input is stored either as “1”or as “0”in a specific memory bit/each input or output has one corresponding bit in memory. Other parts of memory are used to store variable contents for variables used in used program. For example, time value, or counter value would be stored in this part of the memory.PLC controller can be reprogrammed through a computer (usual way), but also through manual programmers (consoles). This practically means that each PLC controller can programmed through a computer if you have the software needed for programming. Today’s transmission computers are ideal for reprogramming a PLC controller in factory itself. This is of great importance to industry. Once the system is corrected, it is also important to read the right program into a PLC again. It is also good to check from time to time whether program in a PLC has not changed. This helps to avoid hazardous situations in factory rooms (some automakers have established communication networks which regularly check programs in PLC controllers to ensure execution only of good programs).Almost every program for programming a PLC controller possesses various useful options such as: forced switching on and off of the system input/outputs (I/O lines), program follow up in real time as well as documenting a diagram. This documenting is necessary to understand and define failures and malfunctions. Programmer can add remarks, names of input or output devices, and comments that can be useful when finding errors, or with system maintenance. Adding comments and remarks enables any technician (and not just a person who developed the system) to understand a ladder diagram right away. Comments and remarks can even quote precisely part numbers if replacements would be needed. This would speed up a repair of any problems that come up due to bad parts. The old way was such that a person who developed a system had protection on the program, so nobody aside from this person could understand how it was done. Correctly documented ladder diagram allows any technician to understand thoroughly how system functions.Electrical supply is used in bringing electrical energy to central processing unit. Most PLC controllers work either at 24 VDC or 220V AC. On some PLC controllers you’ll find electrical supply as a separatemodule. Those are usually bigger PLC controllers, while small and medium series already contain the supply module. User has to determine how much current to take from I/O module to ensure that electrical supply provides appropriate amount of current. Different types of modules use different amounts of electrical current.This electrical supply is usually not used to start external input or output. User has to provide separate supplies in starting PLC controller inputs because then you can ensure so called “pure” supply for the PLC controller. With pure supply we mean supply where industrial environment can not affect it damagingly. Some of the smaller PLC controllers supply their inputs with voltage from a small supply source already incorporated into a PLC.Four：PLC design criteriaA systematic approach to designing PLC software can overcome deficiencies in the traditional way of programming manufacturing control systems, and can have wide ramifications in several industrial applications. Automation control systems are modeled by formal languages or, equivalently, by state machines. Formal representations provide a high-level description of the behavior of the system to be controlled. State machines can be analytically evaluated as to whether or not they meet the desired goals. Secondly, a state machine description provides a structured representation to convey the logical requirements and constraints such as detailed safety rules. Thirdly, well-defined control systems design outcomes are conducive to automatic code generation- An ability to produce control software executable on commercial distinct logic controllers can reduce programming lead-time and labor cost. In particular, the thesis is relevant with respect to the following aspects.In modern manufacturing, systems are characterized by product and process innovation, become customer-driven and thus have to respond quickly to changing system requirements. A major challenge is therefore to provide enabling technologies that can economically reconfigure automation control systems in response to changing needs and new opportunities. Design and operational knowledge can be reused inreal-time, therefore, giving a significant competitive edge in industrial practice.Studies have shown that programming methodologies in automation systems have not been able to match rapid increase in use of computing resources. For instance, the programming of PLC still relies on a conventional programming style with ladder logic diagrams. As a result, the delays and resources in programming are a major stumbling stone for the progress of manufacturing industry. Testing and debugging may consume over 50% of the manpower allocated for the PLC program design. Standards [IEC 60848, 1999; IEC-61131-3, 1993; IEC 61499, 1998; ISO 15745-1, 1999] have been formed to fix and disseminate state-of-the-art design methods, but they normally cannot participate in advancing the knowledge of efficient program and system design.A systematic approach will increase the level of design automation through reusing existing software components, and will provide methods to make large-scale system design manageable. Likewise, it will improve software quality and reliability and will be relevant to systems high security standards, especially those having hazardous impact on the environment such as airport control, and public railroads.The software industry is regarded as a performance destructor and complexity generator. Steadily shrinking hardware prices spoils the need for software performance in terms of code optimization and efficiency. The result is that massive and less efficient software code on one hand outpaces the gains in hardware performance on the other hand. Secondly, software proliferates into complexity of unmanageable dimensions; software redesign and maintenance-essential in modern automation systems-becomes nearly impossible. Particularly, PLC programs have evolved from a couple lines of code 25 years ago to thousands of lines of code with a similar number of 1/O points. Increased safety, for instance new policies on fire protection, and the flexibility of modern automation systems add complexity to the program design process. Consequently, the life-cycle cost of software is a permanently growing fraction of the total cost. 80-90% of these costs are going into software maintenance, debugging, adaptation and expansion to meet changing needs.Today, the primary focus of most design research is based on mechanical or electrical products. One of the by-products of this proposed research is to enhance our fundamental understanding of design theory and methodology by extending it to the field of engineering systems design. A system design theory for large-scale and complex system is not yet fully developed. Particularly, the question of how to simplify a complicated or complex design task has not been tackled in a scientific way. Furthermore, building a bridge between design theory and the latest epistemological outcomes of formal representations in computer sciences and operations research, such as discrete event system modeling, can advance future development in engineering design.From a logical perspective, PLC software design is similar to the hardware design of integrated circuits. Modern VLSI designs are extremely complex with several million parts and a product development time of 3 years [Whitney, 1996]. The design process is normally separated into a component design and a system design stage. At component design stage, single functions are designed and verified. At system design stage, components are aggregated and the whole system behavior and functionality is tested through simulation. In general, a complete verification is impossible. Hence, a systematic approach as exemplified for the PLC program design may impact the logical hardware design.可编程控制器一、PLC概述可编程控制器是60年代末在美国首先出现的，当时叫可编程逻辑控制器PLC（Programmable Logic Controller），目的是用来取代继电器。

plc单片机毕业论文文献翻译中英文对照

外文翻译：The monolithic In order to prevent without authorization the visit or the copy monolithic integrated circuit machine in the procedure, the majority of monolithic integrated circuits all has the encryption to lock the localization or the encryption byte, by protects the internal procedure. If in programming time encrypts locks the localization to enable (locking), is unable with the ordinary programming directly reading in the monolithic integrated circuit the procedure, this is the so-called copy protection or says the fixed function. In fact, such protective measures are very frail, is very easily explained. The monolithic integrated circuit aggressor with the aid of the special purpose equipment or the self-made equipment, using the monolithic integrated circuit chip design in loophole or the software flaw, through the many kinds of technical method, may withdraw the essential information from the chip, gains in the monolithic integrated circuit the procedure. Therefore, has the newest technology extremely as electronic products project engineer which the essential understanding current monolithic integrated circuit attacks, achieves knows oneself and the other side, knows fairly well, can effectively prevent oneself spends the product which the massive moneys and the time laboriously designs the matter occurrence which is counterfeited by a others night between.monolithic integrated circuits attacks technology：At present, attacks the monolithic integrated circuit mainly to have four kind of technologies, respectively is:This technical usual use processor correspondence connection and in the use agreement, the encryption algorithm or these algorithm security loophole carries on the attack. The software attack obtains the success a case in point is to early A T M E L A the T 89 C series monolithic integrated circuit attack. The aggressor has used in this series monolithic integrated circuit cleaning operation succession design loophole, uses from arranges the procedure to lock the localization after the cleaning encryption, stops the next step of cleaning internal program memory data the operation, thus makes to add the dense monolithic integrated circuit not to turn the encryption monolithic integrated circuit, then use programming read-out internal procedure.This technology usually monitors the processor by the high time resolution when the normal operation all power sources and the connection connection simulation characteristic, and through monitors its electromagnetic radiation characteristic to implement the attack. Because the monolithic integrated circuit is an active electronic device, when it carries out the different instruction, the corresponding mains input consumption also correspondingly changes. Like this analyzes and examines these changes through the use special electronic surveying instrument and mathematics statistical method, then gains in the monolithic integrated circuit the specific essential information.the mistake has the technology This technical use exceptionally working condition causes the processor to make a mistake, then provides the extra visit to carry on the attack. Uses the most widespread mistake to have the attack method including the voltage impact and the clock impact. The low voltage and the high voltage attack may usefor to forbid the protection circuit work or to fortected the information. The power source and the clock transient state jump may affect the single scroll instruction in certain processors the decoding and the ece the processor to carry out the misoperation. Perhaps the clock transient state jump can reposition the protection circuit but not to be able to destroy is proxecution.This technology is the direct exposed chip interior segment, then the observation, holds controls, disturbs the monolithic integrated circuit by to achieve the attack goal.In order to facilitate in order to, the people divide into above four kind of attacks technology two kinds, a kind is the invasion attack (physical attack), this kind of attack needs to destroy the seal, then with the aid of the semiconductor test facility, the microscope and the micro locator, several hours even several week time can complete on the special laboratory flower. All micro probes technology all belongs to the invasion attack. Moreover three methods belong to the non- invasion attack, the monolithic integrated circuit which attacks cannot by the physical damage. In certain situation non- invasion attacks is specially dangerous, this is because the non- invasion attack needs the equipment usually to be possible the self-restraint and the promotion, therefore is extremely inexpensive.The majority of non- invasions attack needs the aggressor to have the good processor knowledge and the software knowledge. Is opposite with it, the invasion probe attack then does not need too many initial knowledge,moreover usually may use the one whole set similar technology to cope with the width scope the product. Therefore, the attack often starts to the monolithic integrated circuit from the invasion reverse engineering, the accumulation experience is helpful to the development more inexpensive and the fast non- invasion attack technology.Last step will be seeks the protection melt silk the position and protects the melt silk to expose under the ultraviolet ray. With enlargement factor at least 100 time of microscopes, inputs the foot from the programming voltage the segment to track generally, seeks the protection melt silk.This technical use exceptionally working condition causes the processor to make a mistake, then provides the extra visit to carry on the attack. Uses the most widespread mistake to have the attack method including the voltage impact and the clock impact. The low voltage and the high voltage attack may use for to forbid the protection circuit work or to force the processor to carry out the misoperation. Perhaps the clock transient state jump can reposition the protection circuit but not to be able to destroy is protected the information. The power source and the clock transient state jump may affect the single scroll instruction in certain processors the decoding and the execution.(4) probe technologyThis technology is the direct exposed chip interior segment, then the observation, holds controls, disturbs the monolithic integrated circuit by to achieve the attack goal.In order to facilitate in order to, the people divide into above four kindof attacks technology two kinds, a kind is the invasion attack (physical attack), this kind of attack needs to destroy the seal, then with the aid of the semiconductor test facility, the microscope and the micro locator, several hours even several week time can complete on the special laboratory flower. All micro probes technology all belongs to the invasion attack. Moreover three methods belong to the non- invasion attack, the monolithic integrated circuit which attacks cannot by the physical damage. In certain situation non- invasion attacks is specially dangerous, this is because the non- invasion attack needs the equipment usually to be possible the self-restraint and the promotion, therefore is extremely inexpensive.The majority of non- invasions attack needs the aggressor to have the good processor knowledge and the software knowledge. Is opposite with it, the invasion probe attack then does not need too many initial knowledge,moreover usually may use the one whole set similar technology to cope with the width scope the product. Therefore, the attack often starts to the monolithic integrated circuit from the invasion reverse engineering, the accumulation experience is helpful to the development more inexpensive and the fast non- invasion attack technology.3 invasions attacks general process：The invasion attack first step uncovers the chip seal. Some two methods may achieve this goal: The first kind is dissolves the chip seal completely, the exposed metal segment. The second kind is only moves above the silicon nucleus plastic seal. The first method needs the chip to tests on the jig, with the aid of Taiwan to operate. The second method except needs to have the aggressor certain knowledge and Wants outside skill, but also needs individual wisdom and the patience, but operates relatively quite is convenient.Above the chip plastic may use the knife to open, around the chip epoxy resin may use the aqua fortis perish. The hot aqua fortis can dissolve the chip seal but not to be able to affect the chip and the segment. This process carries on generally under the extremely dry condition, because the water existence possibly can corrode already the aluminum wire connection which exposes.Then first uses the acetone in the supersonic pond to clean this chip by except the remaining nitric acid, then cleans with the clear water by and is dry except the salinity. Not the supersonic pond, jumps over generally this step. In this kind of situation, the chip surface can a little dirty, but not too affects the ultraviolet ray to the chip operation effect.Last step will be seeks the protection melt silk the position and protects the melt silk to expose under the ultraviolet ray. With enlargement factor at least 100 time of microscopes, inputs the foot from the programming voltage the segment to track generally, seeks the protection melt silk.If does not have the microscope, then uses the chip different partially exposes to the ultraviolet ray under and the observed result way carries on the simple search. When operation applies not the opaque slip of paper cover chipby to protect the program memory not by the ultraviolet ray cleaning. Will protect the melt silk to expose in the ultraviolet ray next 5 ~ 10 minutes can broken the protection position protective function, afterwards, will use the simple programming to be possible the direct readout program memory content.Regarding used the protective layer to protect E E P R O the M unit the monolithic integrated circuit to say that, the use ultraviolet ray repositioned the protection circuit is not feasible. Regarding this kind of type monolithic integrated circuit, uses the micro probe technology reading the memory content generally. Opens after the chip seal, puts in the chip under the microscope to be able very easy finding中文翻译单片机为了防止未经授权访问或拷贝单片机的机内程序，大部分单片机都带有加密锁定位或者加密字节，以保护片内程序。

PLC行业常用184个专业英语中英文词汇对照

PLC行业常用184个专业英语中英文词汇对照PLC行业常用184个专业英语中英文词汇对照1. PLC 可编程逻辑控制器2. absolute 绝对位置3. absoluteoutput 绝对输出4 .actuator 执行器/作动器5. against 对比6. allocate 分配 7. alter 改变/修改8. ambient 环境周围ambient operating temperature 9. analog 模拟 analogoutput 10. analysis 分析 thecollection an and analysis of data 12. applicable 可用 the applicableCPU for the module13. assign 分配 14. back up battey 备用电池15. barcode reader/ID 条形码阅读器16. base unit 主基板17. baud 波特 18. beforehand 事先19. binary 二进制 20. buffer memory 缓冲存储器21. bus 总线22. case 外壳 do notremove the modules print board from the case23. characteristic 特征I/Ocharacterristic24. check 校验the datalink status canbe checked25. child-station 子站26. common terminal 公共端27. compatible 兼容 compatiblewith the MODBUS protocol28. compound 混合compoundsystem communication 29. condensation 结露30. condition 条件conditionsetting31. conductive 导电conductivemetal picees32. configuration 组态systemconfiguration33. configure 组态34. confirm 确认how toconfirm the operation of the module35. consumption 消耗currentconsumption36. content 目录37. control level 控制级38. convenient 方便moreconvenient and easy-to-use39. conventionaly 传统whichconventionaly has been used 40. conversion 转换Analog-Digital conversion module41. converter 转换器42. conveyor 传送conveyorline 43. corrosive 腐蚀corrosivegas 44. countermeasure 对策。

PLC常用英文词汇（中文对译）

PLC常用英文词汇（中文对译）在PLC编程中我们经常会遇到一些专业英文词汇，对于入门的学员来说过理解起来是非常困难的。

本文总结了一些PLC常用专业英文词汇，并做已翻译。

01a开头absolute 绝对位置Absolute output 绝对最大输出actuator 执行器/作动器against 对比allocate 分配alter 改变/修改ambient 环境周围ambient operating temperatureanalog 模拟analysis 分析applicable 可用assign 分配02b开头back up battey 备用电池barcode reader/ID 条形码阅读器base unit 主基板baud 波特beforehand 事先binary 二进制buffer memory 缓冲存储器bus 总线03c开头case 外壳characteristic 特征check 校验child-station 子站common terminal 公共端compatible 兼容compound 混合condensation 结露condition 条件conductive 导电configuration 组态configure 组态confirm 确认consumption 消耗content 目录control level 控制级convenient 方便conventionaly 传统conversion 转换converter 转换器conveyor 传送corrosive 腐蚀cutoff 切断countermeasure 对策04d开头debug 调试dedicated 屏蔽dedicated 专用default value 缺省值define 解释/阐明design 设计device level 现场级diagnosis 诊断digital 数字din rail 导轨diverse 不同的/各种各样的download 下载duplicate 完全一样dust 灰尘05e开头eliminate 免得enterprise level 管理级erase 清除exceed 超出execute 执行expand 扩展06f开头faulty 故障站field bus 现场总线fix 固定flexibly 灵活的flow 流量format 格式fuse 融丝07g开头graph图标坐标图曲线guaranteed 担保08h开头handle 处理hardware manual 硬件手册hint 提示humidity 湿度09i开头individual 独立的inductance 电感initiate 实施发起input 输入input point 输入点数install 安装instruction 指令insulation 隔离interface 接口interlocking 互锁internal 内部interrupt 中断invalid 无效10m开头magnetic 有磁性的main circuit 主回路/线电路malfunction 故障mandatory 强制mantenance 维护manual 手册mechanical 机械mechanical life 机械寿命module 模块/组件momentary power failure 瞬时断电monitor 监视mount 固定multiple 多样11n开头negative 负12o开头observation 观察occupy 占用occur 发生offline 离线offset gain 偏置增益oil mist 油雾optical loop 光缆回路optimum 最佳的output 输出overall 总的overview 总揽13p开头parameter 参数path 路径perform 进行performance specifations 性能规格peripheral 外围/外部设备phase 相point 要点port 接口positive 正power line 电源线power>precaution 注意事项print board 印刷电路板procedure 过程programing interface 编程接口/编程界面protocol 协议14r开头range 范围rated input voltage 额定输入电压ratio 比率refer to 参照recommend 建议reduce 减少/缩小register 数据寄存器relay 继电器remote I/O 远程网络reserved station 预留主站resistor 电阻器15l开头load bridging resistor 负载转移电阻load compensating resistor 负荷补偿电阻load shifting resistor 负载移动电阻器 ; 负荷转移电阻load-resistor contactor 负载电阻器接触器 ; 负荷电阻接触器anode load resistor 释义阳极负载电阻 ; 阳极负载电阻effect of load resistor 负载电阻效应16r开头resolution 分辨率Maximum resolution 最大分辨率restriction 限制retry 重试17s开头scan 扫描screw 螺丝seamless network 无缝网络sequence programme 顺控程序serial communications module 串口通信模块series 系列servo 伺服系统short 短路signal 信号sink 漏极slot 周边元件扩展插槽soures 源极specifications 特性stabilized power supply 稳压电源standby master station 备用主站start up 起动status 状态step drive 步进storage 存储store 存储witch off 切断swith 开关18t开头table 表格transfer 传送transistor 晶体管transmission speed 传输速度transmit 传送/传输triac 三端双向可控硅开关元件troubleshooting 故障处理19u开头unuseble 不可以使用upload 上传/上载utilize 利用20v开头verify 校验voltage 电压21w开头watchdog 看门狗定时器width 范围wire chips 线头（涉及领域:电子、电气/电工（考证题库）、通信、维修、自动化、程序等）。

中英文文献翻译-关于PLC外文翻译

外文文献PLC technique discussion and future developmentProgrammable Controller (Programmable Logic Controller, customarily referred to as PLC) is a microprocessor as the core of the general industrial automation devices. Is in the late 1960 s in the relay control system developed on the basis of, it will traditional relay control technology combined with computer technology and communication technology, has a simple structure, superior performance, high reliability, flexible, general and convenient use, easy to programming. In particular, the characteristics of the PLC is shown as the followingAspects: (1) the high reliability of hardware. PLC is specialized in industrial environment under the conditions of application and design. Can be placed in a well designed PLC has a very high voltage noise, electromagnetic interference and mechanical vibration, extreme temperature, and humidity environment. Is in the aspect of hardware design, first of all with high quality components, and adopt reasonable system structure, strengthening, simplify installation, makes it easy to anti vibration shock, to the printed circuit board design, machining and welding process are taken very strict measures, and on the circuit, the structure and process had taken some unique ways. Because the PLC itself has very high reliability, so in the event of a failure parts mostly focused on the input/output parts and such as sensors, limit switches, photoelectric switch, electromagnetic valve, motor, etc. programming and easy to use. Automatic control by microcomputer, commonly used assembly language programming, difficult to grasp, requires the user has a certain level of knowledge of computer hardware and software. PLC used for process control, problem oriented programming method, compared with the currently used assembly language microcomputer control, while inside the PLC increases the interpretation procedure, to increase the program's execution time, but for most of the mechanical and electrical control equipment, this loss is negligible. (3) Wiring is simple, high universality. In the case of electrical matching, PLC connection just put the input signal of the device (button, switch, etc.) connected to the input terminal of PLC, will accept the output signal of executive control tasks (contactor, solenoid valves), executive components connected to the PLC output terminals. Wiring is simple, leaves out the conventional relay control system wiring and removing the trouble. PLC programming logic provides can change according to the requirements of logical relationship, so that production line automation process can change at will. This performance makes the PLC has the very high economic benefits. Used to connect field devices of the hardware interface design has actually become a part of PLC, since the diagnosis of modular interface circuit can point to the fault, and easy to troubleshooting and replacement of fault parts, so that the software and hardware design of the site electrical personnel and technical personnel to use. (4) can be connected tocontrol network system. PLC can be connected to become powerful network system. General PLC network can be divided into two kinds: one kind is a low-speed network, USES the master-slave mode communication, transfer rate from the potter thousands and thousands of potter to the transmission distance is 500 ~ 2500 m; Another kind of high-speed network, USES the token passing mode communication, communication rate of 1 m to 10 MBPS, transmission distance is 500 ~ 1000 m, 1024 online nodes. These two types of networks are linked together, can be compatible with different types of programmable controller and computer, forming control range a lot of local network. 5. Easy to install, easy to maintain. PLC installation is simple and powerful functions, its relatively small size allows them to install the relay control box usually required for half of the space. In the large PLC system installation, remote I/o in the optimal location. Remote I/O station through double axis of coaxial cable, or even to the CPU, which greatly reduces the material and labor, remote subsystem method means from different parts of the system can be installed in field. Because almost all of the components are modular, only need to change when maintaining module level plug-in components, fault detection circuit diagnosis indicator will be embedded in each part, can indicate the device is working correctly, the resistance in programming is visible input/output devices ON or OFF, still can write programming instructions to report failures. In addition, PLC automation technology, computer technology and communication technology together, and you can also complete the following functions: logic control, timing control, counting control, stepper control, A/D and D/A conversion, data processing, communication network and monitoring on the control system. In general, the application of PLC have boom in the world, the PLC development direction mainly toward miniaturization, deflationary force, standardization, standardization, intelligence, high speed, large capacity, network development, this will make the PLC function is stronger, higher reliability, more convenient use, wide application and moreThe PLC biggest characteristics lie in: The electrical engineering teacher already no longer electric hardware up too many calculations 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 themachine and I/ Os to connect, saving machine separately saving machine RAM of the procedure saving machine ROM and dates, the ROM 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 equipments, 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, and it combines with the PLC to our larger space.HMI the control not 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, and 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 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 body now its value, at the PLC and correspondence between PLC, can pass the communication of the information and the share of the dates 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 workers .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 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 canting have an error margins in a dates 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 equipments, 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 andaccept, 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 contains 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 differentiations 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 ocular transmission speed is very quick of, it is a string of ocular 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 deposited 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 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 equipment always will not forget a button, it also is at we meet the urgent circumstance use of, which 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 that the high class counts the machine, being us while accept some dates of high speed, the high speed that here say is the data of the in all aspects tiny second class, for example the bar code scanner is scanning the data continuously, calculating high-speed signal of the data processor DSP etc., we will adopt the high class to count the machine to help we carry on count. It at the PLC carries out the procedure once discover that the high class counts the machine to should of interruption, will let go of the work on the hand immediately. The trapezoid diagram procedure that passes by to weave the distance again explains the high class for us to carry out procedure to count machine would automatic performance to should of work, thus rise the Class that the high class counts the machine to high one Class.You heard too many this phrases perhaps:" crash", the meaning that is mostly is a workload of CPU to lead greatly, the internal resources shortage etc. the circumstance can't result in procedure circulate. The PLC also has the similar circumstance, there is a watchdog WDT in theinner part of PLC, we can establish time that a procedure of WDT circulate, being to appear the procedure to jump to turn the mistake in the procedure movement process or the procedure is busy, movement time of the procedure exceeds WDT constitution time, the CPU turn but the WDT reset the appearance. The procedure restarts the movement, but will not carry on the breakage to the interruption.The PLC development has already entered for network ages of correspondence from the mode of the one, and together other works control the net plank and I/ O card planks to carry on the share easily. A state software can pass all se hardwires link, more animation picture of keep the view to carries on the control, and cans pass the Internet to carry on the control in the foreign land, the blast-off that is like the absolute being boat No.5 is to adopt this kind of way to make airship go up the sky.The development of the higher layer needs our continuous effort to obtain. The PLC emergence has already affected a few persons fully, we also obtained more knowledge and precepts from the top one experience of the generation, coming to the continuous development PLC technique, push it toward higher wave tide.Knowing the available PLC network options and their best applications will ensure an efficient and flexible control system design.The programmable logic controller's (PLC) ability to support a range of communication methods makes it an ideal control and data acquisition device for a wide variety of industrial automation and facility control applications. However, there is some confusion because so many possibilities exist. To help eliminate this confusion, let's list what communications are available and when they would be best applied.To understand the PLC communications versatility, let's first define the terms used in describing the various systems.ASCII: This stands for "American Standard Code for Information Interchange." As shown in Fig. 1, when the letter "A" is transmitted, for instance, it's automatically coded as "65" by the sending equipment. The receiving equipment translates the "65" back to the letter "A." Thus, different devices can communicate with each other as long as both use ASCII code.ASCII module: This intelligent PLC module is used for connecting PLC to other devices also capable of communicating using ASCII code as a vehicle.Bus topology: This is a linear local area network (LAN) arrangement, as shown in Fig. 2A, in which individual nodes are tapped into a main communications cable at a single point and broadcast messages. These messages travel in both directions on the bus from the point of connection until they are dissipated by terminators at each end of the bus.CPU: This stands for "central processing unit," which actually is that part of a computer, PLC, or other intelligent device where arithmetic and logical operations are performed and instructions are decoded and executed.Daisy chain: This is a description of the connection of individual devices in a PLC network, where, as shown in Fig. 3, each device is connected to the next and communications signals pass from one unit to the next in a sequential fashion.Distributed control: This is an automation concept in which portions of an automated system are controlled by separate controllers, which are located in close proximity to their area of direct control (control is decentralized and spread out over the system).Host computer: This is a computer that's used to transfer data to, or receive data from, a PLC in a PLC/computer network.Intelligent device: This term describes any device equipped with its own CPU.I/O: This stands for "inputs and outputs," which are modules that handle data to the PLC (inputs) or signals from the PLC (outputs) to an external device.Kbps: This stands for "thousand bits per second," which is a rate of measure for electronic data transfer.Mbps: This stands for "million bits per second."Node: This term is applied to any one of the positions or stations in a network. Each node incorporates a device that can communicate with all other devices on the network.Protocol: The definition of how data is arranged and coded for transmission on a network.Ring topology. This is a LAN arrangement, as shown in Fig. 2C, in which each node is connected to two other nodes, resulting in a continuous, closed, circular path or loop for messages to circulate, usually in one direction. Some ring topologies have a special "loop back" feature that allows them to continue functioning even if the main cable is severed.RS232. This is an IEEE standard for serial communications that describes specific wiring connections, voltage levels, and other operating parameters for electronic data communications. There also are several other RS standards defined.Serial: This is an electronic data transfer scheme in which information is transmitted one bit at a time.Serial port: This the communications access point on a device that is set up for serial communications.Star topology. This is a LAN arrangement in which, as shown in Fig. 2B, nodes are connected to one another through a central hub, which can be active or passive. An active hub performs network duties such as message routing and maintenance. A passive central hub simply passes the message along to all the nodes connected to it.Topology: This relates to a specific arrangement of nodes in a LAN in relation to one another.Transparent: This term describes automatic events or processes built into a system that require no special programming or prompting from an operator.Now that we're familiar with these terms, let's see how they are used in describing the available PLC network options.PLC network optionsPLC networks provide you with a variety of networking options to meet specific control and communications requirements. Typical options include remote I/O, peer-to-peer, and host computer communications, as well as LANs. These networks can provide reliable and cost-effective communications between as few as two or as many as several hundred PLC, computers, and other intelligent devices.Many PLC vendors offer proprietary networking systems that are unique and will not communicate with another make of PLC. This is because of the different communications protocols, command sequences, error-checking schemes, and communications media used by each manufacturer.However, it is possible to make different PLC "talk" to one another; what's required is an ASCII interface for the connection(s), along with considerable work with software.Remote I/0 systemsA remote I/O configuration, as shown in Fig. 4A, has the actual inputs and outputs at some distance from the controller and CPU. This type of system, which can be described as a "master-and-slave" configuration, allows many distant digital and analog points to be controlled by a single PLC. Typically, remote I/Os are connected to the CPU via twisted pair or fiber optic cables.Remote I/O configurations can be extremely cost-effective control solutions where only a few I/O points are needed in widely separated areas. In this situation, it's not always necessary, or practical for that matter, to have a controller at each site. Nor is it practical to individually hard wire each I/O point over long distances back to the CPU. For example, remote I/O systems can be used in acquiring data from remote plant or facility locations. Information such as cycle times, counts, duration or events, etc. then can be sent back to the PLC for maintenance and management reporting.In a remote I/O configuration, the master controller polls the slaved I/O for its current I/O status. The remote I/O system responds, and the master PLC then signals the remote I/O to change the state of outputs as dictated by the control program in the PLC memory. This entire cycle occurs hundreds of times per second.Peer-to-peer networksPeer-to-peer networks, as shown in Fig. 4B, enhance reliability by decentralizing the control functions without sacrificing coordinated control. In this type of network, numerous PLC are connected to one another in a daisy-chain fashion, and a common memory table is duplicated in the memory of each. In this way, when any PLC writes data to this memory area, the information is automatically transferred to all other PLCs in the network. They then can use this information in their own operating programs.With peer-to-peer networks, each PLC in the network is responsible for its own control site。

PLC的工作原理中英文翻译

PLC的工作原理可编程控制器，英文称ProgrammableLogicController，简称PLC。

PLC是基于电子计算机，且适用于工业现场工作的电控制器。

它源于继电控制装置，但它不像继电装置那样，通过电路的物理过程实现控制，而主要靠运行存储于PLC内存中的程序，进行入出信息变换实现控制。

PLC基于电子计算机，但并不等同于普通计算机。

普遍计算机进行入出信息变换，多只考虑信息本身，信息的入出，只要人机界面好就可以了。

而PLC则还要考虑信息入出的可靠性、实时性，以及信息的使用等问题。

特别要考虑怎么适应于工业环境，如便于安装，抗干扰等问题。

当PLC投入运行后，其工作过程一般分为三个阶段，即输入采样、用户程序执行和输出刷新三个阶段。

完成上述三个阶段称作一个扫描周期。

在整个运行期间，PLC的CPU以一定的扫描速度重复执行上述三个阶段。

1．输入采样阶段在输入采样阶段，PLC以扫描方式依次地读入所有输入状态和数据，并将它们存入I/O映象区中的相应得单元内。

输入采样结束后，转入用户程序执行和输出刷新阶段。

在这两个阶段中，即使输入状态和数据发生变化，I/O映象区中的相应单元的状态和数据也不会改变。

因此，如果输入是脉冲信号，则该脉冲信号的宽度必须大于一个扫描周期，才能保证在任何情况下，该输入均能被读入。

2.用户程序执行阶段在用户程序执行阶段，PLC总是按由上而下的顺序依次地扫描用户程序(梯形图)。

在扫描每一条梯形图时，又总是先扫描梯形图左边的由各触点构成的控制线路，并按先左后右、先上后下的顺序对由触点构成的控制线路进行逻辑运算，然后根据逻辑运算的结果，刷新该逻辑线圈在系统RAM存储区中对应位的状态；或者刷新该输出线圈在I/O映象区中对应位的状态；或者确定是否要执行该梯形图所规定的特殊功能指令。

即，在用户程序执行过程中，只有输入点在I/O映象区内的状态和数据不会发生变化，而其他输出点和软设备在I/O映象区或系统RAM存储区内的状态和数据都有可能发生变化，而且排在上面的梯形图，其程序执行结果会对排在下面的凡是用到这些线圈或数据的梯形图起作用；相反，排在下面的梯形图，其被刷新的逻辑线圈的状态或数据只能到下一个扫描周期才能对排在其上面的程序起作用。

PLC中英文资料外文翻译

可编程控制器技术讨论与未来发展学生姓名： ******所在院系： ******所学专业： ******导师姓名： ******完成时间：******外文资料PLCtechnique discussion and future developmentWith the development of the times, today's technology is maturing, competition intensified。

rely on manual operation does not satisfy the current industry outlook, there is no guarantee of higher quality requirements and high-tech corporate image.People saw in the production practice, automation to bring great convenience and product quality assurance, but also reduce the labor intensity, reducing the staff on the establishment in many complex production process is difficult to achieve target control, the overall optimization, optimal decision-making, skilled operatives, technicians or specialists, managers can easily determine and operate it, you can get satisfactory results. artificial intelligence research is the use of computers to achieve the target, the analog These intelligent behavior, through coordination of the human brain and a computer to combine human models for solving very complex problem of finding the best way.PLC's most important feature is: electrical engineer electrical hardware no longer spend too much scheming, as long as the button switch or sensor input connected to the PLC input point will solve the problem by connecting the output point contacts or relay to control the power of the boot device, and small power output devices can be connected directly.Contained within the PLC having a central processor of the CPU, and with an external I / O port expansion I / O interface and the memory addresses of three major components, CPU core is formed by one or more accumulators, which have the logical math capabilities, and can read the contents of the program memory to drive through the calculation of the corresponding memory and I / O interface。

可编程控制器应用中英文对照外文翻译文献

可编程控制器应用中英文对照外文翻译文献中英文对照外文翻译Support software for the development ofprogrammable logic1、IntroductionProgrammable Logic Controllers (PLC) class of real-time computers used extensively in industrial control applications. The development of a PLC application requires the configuration of the inputs and outputs of the PLC architecture, that is the selection of the number, type and addresses of the inputs and outputs of the PLC, and the writing and debugging of the application program. Programming these computers is usually done in specific graphical structured text languages [Bekkum93,Hughes 89,Jones 83] and the program debugging is carried out in a development environment. Most of the available environments [Square D 90, Taylor 90] allow program writing in more than one language, running it by step or in segments on the actual PLC and checking whether the assumed logical relationships between the inputs and the outputs at each program step or segment are satisfied. I addition, these environments offer engineering support, such as the preparation of input/output wiring diagrams and the generation of the executable code of the program. Recent versions of commercially available environments are supplied with a software emulator of one or more PLC units. This allows to perform program debugging without having access to the programmable controller itself. Also, the use of emulators makes easier and economically affordable the simulation of a large number of program operating conditions. By making sure that the programoperates correcty under all the critical operating conditions, the risk of implementing aPLC-based system that does not meet the desired requirements is reduced. However, the ultimate goal of a development environment should be to verify the functional properties and behavior of the programs in all the possible states that thes programs and the plants they may enter.In the literature, various languages and graphical or mathematical formalisms are proposed for writing or specifying real-time programs .The timing and/or functional performance of these programs can be verified at compile time or mathematically. ADA[Ada83],RT-ASLAN[Auemheimer86], EUCLID[Kligerman86], PEARL [Halang 91], FLEX[Lin88] are some of the proposed and most widely known languages. Their graphical or mathematical formalisms are based on the use of finite state automata [Alford 77],Petri-Nets[Fedler 93], dataflow diagrams [Zave 82] and metric temporal logic [Koymans 90]. Although all these formal methods and languages represent significant advances to the problem of real-time program verification, still they have not reached the maturity required to deal with the complexities of large software systems . Until these methods reach a certain level of maturity we must rely on less formal methods, tuned to the needs of specific classes of real-time systems.In the case of PLC, we may continue to use simulation as a method to reveal logical errors in our programs and assess their behavior under an incomplete set of possible program states. In addition, we may include new facilities in the program development environments, the use of which will reduce the programming and engineering effort of an application. They maybe editing and compilation facilities which support application programming in all the languages defined in the IEC 1131-3 standard. By using these languages our programming efficiency will be improved significantly, because each one of them can be used to program the part of the application for which it is appropriate, and yet the whole application can be linked into a single executable program. Other facilities which can reduce engineering effort are those whichcan make easier and more meaningful the declaration of the program input conditions. These facilities will allow us to study in a given timing period, a larger number of simulation cases than the ones we might have studied without these facilities. Furthermore, we may expand the scope of the simulation by including a simulator of the plant which interacts with the computer. Also, facilities can be added to assist in the better interpretation of the generated simulation results. Such facilities may allow us to configure the displays of the generated data the way we think appropriate, and animate the simulated operation of the application program.In this paper an architecture and language constructs are proposed for a software aid which ~an be used to declare input conditions to a PLC program, emulate the PLC operation and configure the display of the emulation results. The core of the architecture is the virtual machine, which is a software module which emulates the operation of a program written for a specific PLC in any application programming language. The virtual machine is linked with executable code generated from two other software modules which interpret instructions defining the input conditions to the application program and the configuration of the output display. Of course, the proposed facilities do not solvethe problem of the complete verification of the timing behavior of an application program. However, when they are compared with the facilities offered by various commercially available aids, to our opinion they do significantly reduce the time taken to test the execution of a PLC program under a large number of possible input conditions, on different architectures and interpret the results. A scaled down experimental implementation of facilities for a specific PLC model is used to demonstrate the feasibility of the proposed concepts. The operation of the experimental set-up has been validated with data taken from the execution of sample program on a specific PLC.1、Principles of PLC Operation.The Programmable Logic Controller is a special purpose digital computer designed to control machine or process operations by means of a stored program and feedback from input/output field devices. It is composed primarily of two basic sections: the Central Processing Unit (PLC) and an Input/Output(I/O) interface. The CPU encompasses all the necessary elements that form the intelligence of the system. It is further subdivided to the Processor, Memory and Power supply. The CPU accepts input data from various input field devices, executes the stored program from the memory, and sends appropriate commands to output field devices. The Input/Output system forms the interface by which the field devices are connected to the controller. Its purpose is to condition the various signals received from or sent to field devices. Through this system the CPU can sense and measure physical quantities regarding a machine or process, such as proximity, position, motion, level temperature, pressure, current and voltage. Based on the status sensed or values measured, the CPU, through thisinterface system, issues commands that control various devices such as valves, motors, pumps and alarms. The most common type of I/O interface is the discrete one. This interface connects field input or output devices, which provide input signals or receive command signals of the Boolean type.Pushbuttons, limit switches and selector switches are some of the devices that provide incoming signals of this type,, whereas typical field devices that can be and position valves .The numerical I/O interface is another type of interface, provided in a PLC system. It can allow reading or writing a multi-bit digital or analog device. Multi-bit devices either generate or receive a group of bits which is the digital representation of a decimal number or an analogue quantity. This group of bits is handled as a unit by the CPU and can be in parallel form (BCD inputs or outputs) or in serial form (pulse inputs or outputs). Typical field devices providing multi-bit input to a PLC are thumbwheel switches, bar code readers and encoders ,whereas typical output devices are seven-segment and intelligent displays. The analogue field devices are the various sensors, motor drives, and process instruments used to monitor arid control physical variables such as temperature, pressure, humidity, flow, etc. The devices which monitor physical variables send to the I/O interface analogue voltages and currents which are converted by the A/D converter of the interface to a multi-bit digital code. On the other hand, an analogue device used to control the value of a physical variable, receives from the interface an analogue voltage or current as a result of the digital to analogue conversion of data produced by the CPU.The processor of the CPU performs all the mathematical operations, data handling and diagnostic routines by executinga collection , stored in the memory .This collection consists of supervisory programs ,that are permanently stored in the memory, and application programs . The supervisory programs, known as the executive, allow communication with the processor via a programming device or other peripheral memory management, monitoring of field devices, hardware fault diagnosis and execution of the application program written by the user. The memory organization and the way the application program is executed under the control of the executive are two features which distinguish a PLC from any other general purpose computer. In general, all PLC have memory allocated for executive programs, processor work area, data table and application program. The programmed instructions and any data that will be utilized by the processor to perform its control functions are stored in the Application Program Memory Area and Data Table Memory Area respectively. These two areas can be grouped into what is called application memory. Each controller has a maximum amount of application memory which is part of the total memory specified for the controller. The Data Table is functionally divided Into the Input Table, Internal Storage Area and Storage Registers Area. The Input Table is an array of bits that stores the status of the digital inputs which are connected to the I/O interface system.. The Output Table is an array of bits that control the status of the digital output devices, which are also connected. To the I/O system. The Internal Storage Bits Area is the memory area allocated for thestorage of the logic status of flags used by the application program. The Storage Registers Area is allocated for the storage of input registers, holding registers and output registers. The input registers are used to store numerical data received viadigital of analogue input interfaces. The holding registers are used to store variable values that are generated by math, timer and counter instructions of a program. The output registers are used to provide storage for numerical or analogue values that control various output devices .Each virtual machine program is built according to a general computer model applicable to any PLC architecture. This model maps the usual functions performed by a PLC to machine language functions of a simple hypothetical computer. This computer consists of:(a) a Central Processing Unit (CPU)(b) a Memory unit(MU) where the application program is stored and(c) a number of Input and Output modules(I/O)At system start up, the execution of the executive program is initiated. During this program execution, the processor reads all the inputs, stores their values in the Input Storage Area and runs the application program. The results which are generated during the execution of the application program are saved in the Output Storage Area. The process of reading the inputs, executing the program, and updating the outdate all the outputs of the PLC by suing the data of the Output Storage Area. The process of reading the inputs, executing the program, and updating the outputs is known as scan. The time required to make a single scan is called scan time. A figure for the worst case time is usually provided by the manufacturers. Generally, they specify the maximum scan-time that corresponds to every 1K of programmed memory, i.e. 10msecs/1k. However, since the common method of monitoring the inputs at the end of each scan is inadequate for reading certain extremely fast inputs,some PLC provide software instructions that allow the interruption of the continuous program scan in order to receive an input or update an output immediately. Also, a newer approach inPLC design, which results to a significant reduction of the total processing time, is to divide the total system load to a number of tasks and assign their execution to several processors.The stack register is so designed that the execution of an instruction which reads discrete inputs shifts right by one bit the contents of the stack register and pushes the current state of the O.R flip flop into stack register. When this operation is completed, the O.R flip flop is loaded with the state of a discrete input. Instructions which perform logic operations shift left the contents of the stack register. Then, the leftmost bit of the stack register is loaded into the O.R flip flop. Then, the arithmetic, calculations and numerical handling are using the data registers DROO and DRO1 for byte and word operations respectively.可编程控制器应用的发展支持软件1、序可编程控制器（PLC）构成了工业的控制应用中被广泛地应用的即时计算器的一个类别。

PLC及变频器技术中英文对照外文翻译文献

(文档含英文原文和中文翻译)中英文资料对照外文翻译PLC and inverter technology trends1. The development trend of the programmable controller“PLC is one kind specially for the digital operation operation electronic installation which applies under the industry environment designs. It uses may the coding memory, uses for in its internal memory operation and so on actuating logic operation, sequence operation, time, counting and arithmetic operation instructions, and can through digital or the simulation-like input and the output, controls each type the machinery or the production process. PLC and the related auxiliary equipment should according to form a whole easy with the industrial control system, easy to expand its function the principle to design.”In the 21st century, PLC will have a bigger development. Technologically speaking, computer technology's new achievement more will apply in the programmable controller's design and the manufacture, will have the operating speed to be quicker, the storage capacity to be bigger, an intelligent stronger variety to appear; Looked from the product scale that further develops to subminiature and the ultra-large direction; Looked from the product overcoatability that the product variety will be richer, the specification to be more complete, the perfect man-machine contact surface, the complete communication facility will adapt eachindustrial control situation demand well; Looked from the market that various countries will produce the multi-variety product the situation to break respectively along with the international competition aggravating, will present the minority several brand monopoly international market the aspect, will present the international general programming language; Looking from the network state of play, the programmable controller and other industrial control computer network constitution large-scale control system is the programmable controller technology development direction. Present computer collection and distribution control system DCS (Distributed Control System) had the massive programmable controller application. Is following computer network's development, the programmable controller takes the automation directed net and the international universal network important component, outside industry and industry numerous domain display more and more major function.2. Inverter technology development trendsInverter into the practical phase of more than 1 / 4 century during this period, the frequency converter technology as the basis of power electronics technology and microelectronics technology manager of a leap in the development, as the new power electronic devices and high-performance microprocessor The application of control technologyand the development of increasingly high cost performance of the inverter, more and more small size, but manufacturers are still in constant frequency converter to achieve the further miniaturization and doing new efforts. From a technical point of view, with the frequency converter to further expand the market of the future, with the converter and inverter technology will be on the development of technologies in the following areas further development:(1) large capacity and small size;(2) high-performance and multi-function;(3) enhance the ease-of-use;(4) increase in life expectancy and reliability;(5) of pollution-free.Large capacity and small size of the power semiconductor devices will be with the development of continuous development. In recent years, driven by a voltage power semiconductor devices IGBT (Isolated Gate Bipolar Transistor, isolation gate bipolar transistors) has developed very rapidly and quickly into the traditional use of BJT (bipolar power transistor) and power MOSFET (FET) The various fields. In addition, the IGBT switching device for the IPM (Intelligent Power Module, IPM) and Monolithic Power IC chip will power switching devices and driving circuit,such as the protection of integrated circuits in the same package, with high performance and reliability The merits, with their high current and high pressure of the development of small and medium-sized converter will certainly be more widely used.With micro-electronics technology and semiconductor technology development, for Inverter CPU and semiconductor devices and a variety of sensors of getting higher and higher. With the frequency converter technology and the development of the growing maturity of the exchange governor, modern control theory are constantly new applications. These have further improved the performance of inverter provided the conditions. In addition, with the frequency converter to further promote the use and support are also constantly made new demands, the frequency converter manufacturers to continuously improve the performance and frequency converter functions in Inverter new efforts to meet user And the need for the fierce competition in the market in an invincible position.With the frequency converter market continues to expand, how to further enhance the ease-of-use inverter, so that the technical staff and even ordinary non-technical staff can quickly master the use of frequency converter technology has become manufacturers must consider the issue. Because only easy-to-use products can continue to acquire new customersand further expand the market, so the future of the new converter will be more easy to operate.With the development of semiconductor technology and the development of power electronics technology, the frequency converter used in the various components of the life and reliability are constantly improving, they will make their own life and the frequency converter to further increase reliability.In recent years, people have attached great importance to environmental issues, and thus a "green products" name. Therefore, the inverter, must also consider its impact on the surrounding environment.Promote the use of the frequency converter in the early stages of the noise problem was once a big problem. With the low-noise converter IGBT the emergence of this issue has basically been resolved. However, with the noise problem to solve, people's looks and a converter to the surrounding environment and the impact of other continuously explore new solutions. For example, the use of a diode-voltage converter and PWM inverter circuit converter, the frequency converter itself the high harmonics will bring supply voltage and current distortion, and at the same power to affect the other equipment. However, through the use of the frequency converter Rectifier circuit PWM, we can basically solve the problem. Althoughbecause of price and control technology and other aspects of the reasons for the current PWM converter has not been promoting the inverter, but, with the frequency converter technology development and the people of the importance of environmental issues.PLC及变频器技术的发展趋势1．可编程控制器的发展趋势可编程控制器是一种数字运算操作的电子系统，专为在工业环境下应用而设计。

plc英文翻译

外文文献原稿和译文原稿IntroductionPLC-Programmable Logic Controllers are widely used in recent years the field of industrial control Such as metallurgy, steel, production lines, etc Its main feature is its stable performance, high control precision and easy maintenance. With PC connection, compiled in the production process according to the corresponding program will convert digital signals into analog signal input commands output instructions to control the implementation of components to achieve automatic control purposes. Currently, the main aspects of the music program-controlled fountain imported lighting console and its matching control decoder, once the failure is not easy to repair, the price is more expensive. Using PLC technology, you can use an ordinary PC to replace imported lighting control, easy maintenance, low cost PLC article on how to use music technology to analyze the problem of program-controlled fountain.PLC's programmable fountainFountain is the use of the work produced by the pump pressure, nozzle jet out from the water column, the number of pumps in accordance with a certain type, location, installation, combining different types of nozzles, can have a variety of flower. We can each pump as a working point, programming, the module through the PLC to control each point, that is, through the implementation of the loop on each pump, or gear engagement control, to control the pump The purpose of the work of the state.To demonstrate the artistic fountain, usually accompanied by a corresponding track, according to the rhythm of the selected track speed, cadence, the preparation of the appropriate pump control procedures to reflect the music's meaning. The most important aspect is the time synchronization, the music is about playing time based on rhythm and sense of music divided into several time periods, the preparation of the corresponding time period in each of the pumps, lighting control program, theprecision adjustment of track time and PLC accuracy of programming the same time, but at the same time period, water pumps and lighting same working hours as a subroutine to achieve synchronization in the visual viewing.At night with lights to enhance the fountain of viewing, optional programmable control of the LED lighting, through the RS485 interface access control, to be completed by their centralized control. According to the light color, light floral point of view, music tracks for the preparation of procedures, working hours have lights and music, pump time synchronization, the principle and the control of pumps on the same principle, will not repeat them here.Implementation stepsPump controlAccording to the model pump, flower shape and distribution of the location, the uniform numbers, and the number of points with the number-one correspondence PLC module, the pump will be the same flower formation, flower-shaped water pump for each work order, work (as a whole or separately ) for permutations and combinations, preparation of the corresponding subroutines and numbered, giving the corresponding number of working hours to control the pump working hours, working hours type of sustainable, can also be stopped, the performance of both static and dynamic form of In addition, by adding the drive to track the performance of a flower-shaped soft, add the beauty of the fountain. Between the PLC and inverter in the corresponding equivalent between the PLC's digital signal is converted to analog converter controls the pump speed signal, the dynamic work of pump status, and then flower the shape of the requirements of its permutations and combinations, preparation of subroutine and the corresponding number.Lighting controlAccording to the color of light (preferably choose red, yellow, and blue primary colors), the installation location, radiation angle, the lighting state of the permutations and combinations of work, preparation of the corresponding routines, giving the corresponding number of working hours, time and type of flower-shaped water pump , values consistent with the color can be the same, you can also reflect the dynamicinconsistency can also be a two or a superposition of three colors to produce other different colors, rich colors of light.Time synchronizationThis is the entire music program-controlled fountain control the most important and most critical part, because the music program-controlled fountain show the overall effect of the coordinated directly with the time synchronization has a very close relationship, if time synchronization is different, it will lead to music, floral and lighting are not a whole, viewing greatly reduced, so this link is the core link."Time synchronization" here includes the three levels of time. First, is the precision of music playback time and the PLC control program consistent with the precision of time, and while the relationship between the two start and stop; Second, according to the rhythm of music tracks, the momentum of the play by length of time, with the corresponding pumps, lights the continuing work of the subroutine the same length of time, that is, the pump light to flower and produce the music and change tracks, or watch when there will be music, flower-shaped and light three close enough relationship between, there is a feeling out of touch dissonant; Third, at the same time period, flower-shaped water pump and lighting the work routine time, consistent with persistent or intermittent, the time to consider the specific values of human persistence of vision time, this flower-shaped water pump and lighting will form a whole, both start and end, uniform, flower-shaped one on one program and lighting program can also be many to many, rich ornamental effect.Using Windows Media Player ActiveX provides interface can directly control the software (such as Siemens WinCC) call the player to play music, and also by the location of the current music. Has been playing music, and current information can be convenient to achieve integration through the program each time the song of the need to show a variety of fountain patterns. For example, select a time segment here, in the music section of an integer multiple of the basic length of time a small fountain on the pre-establishment of basic good action, when the late preparation of the overall pattern will be more easy to manage.Music selections, PLC establishment of control proceduresSelect the rhythm of music selections should change significantly, the momentum of the track cadence, no significant difference as far as possible not to select the rhythm, the momentum of change is not prominent in the track that would make the process of the preparation of the larger pattern of problems, but also may lead to the fountain The overall effect is not obvious.Once the music track selected, we must play by the time period, according to rhythm, musical divide, can also be divided using professional music software and recording a good time has been divided. This process is repeated scrutiny, to ensure the accuracy of division of time in order to finally be able to get better overall results. Then, according to a good time has been prepared by the procedure, the selected program when the paragraph with the performance of music content, momentum and emotional harmony, fully embodies the results. Subroutine approach taken here to complete the whole effect of the first song of the flower, in the preparation of the whole pattern when the first song is just the basic movements in a predetermined arrangement on the basis of, modify, track corresponding action spectrum more efficiently. Thus, in the beginning of each time section, only this time with the music turned the basic pattern of routine action (including pumps and lighting program), so relatively easy to do music, fountains, lighting, closely.DebuggingProgramming is completed, the work of making work PLC interface (with remote performance of the current state of the fountain), you can see the entire piece of music in all of the programs of all time period and at the same time period, the pumps on and off and the light action spectrum and demonstrate the implementation of the various components of each moment of the execution state, so you can see results in the field by viewing, recording the feelings of others asked to record the part that needs to be adjusted, modified action spectrum of the corresponding program content, change the order of the corresponding subroutine call, so that the fountains and lights and music with the better.Sound outputDirectly to the computer's sound card to output the audio signal mixer access and power amplifier, equalizer, Compression and other audio equipment in series, the last speaker output from the music scene.PLC configurationControl points can be determined according to PLC hardware configuration.Fountain water pump station according to the overall number, 1 pump contactor control module on the PLC corresponding to a digital output point, an inverter controlled pump module on the PLC corresponding to an analog output point, a separate control group LED lights corresponding to a digital output point, according to their total number to configure the PLC's hardware. Such as PLC use 32 point digital output modules, by calculating the type of module will be able to get the required amount.According to the specific work environment, and may need to select the appropriate lightning protection equipment, to complete the system protection.译文引言PLC-Programmable Logic Controllers(可编程逻辑控制器)近年来被广泛应用于工业控制领域,如冶金、钢铁、生产线等等,其主要特点就是其性能稳定、控制精度高、维护方便。

PLC控制系统英文文献+翻译

PLC控制系统英文文献+翻译PLC控制系统英文文献+翻译Beer filling, Gland machine PLC control system 1.Intorduction Malt beer production process is divided into manufacturing, manufacturing wort, before fermentation, after fermentation, filtration sterilization, packaging, and so few procedures. Beer filling, Gland part of a packaging machine processes. The membrane filtration of beer after the pipeline into the rotary Jiugang, then the valve into the bottle of wine, Gland, was bottled beer. Beer filling, Gland machine's efficiency and degree of automation direct impact on the level of beer production.China's beer industry to meet the increasing scale of production and the demand for beer modern high-speed filling machinery filling the requirements of domestic beer manufacturers are actively seeking to transform the unit or the filling of beer production equipment, making it a good use Performance, advanced technology and high production efficiency and operating a safe and secure, low maintenance costs of the modernization of beer filling machine. 2. Filling beer, Gland principle and control aircraft partsLiquid filling machine by filling principle can be divided into atmospheric filler,filling machines and vacuum pressure on the filling machine. Beer filling,Gland-filling method used pressure is higher than the atmospheric pressure under the filling, storage of the cylinder pressure than the pressure of the bottle, beer bottle into the liquid on pressure.Technology at home and abroad to achieve the filling line is basically: The Rotary Jiugang the rotating movement, placed in Jiugang slots on the empty bottles through the machinery will befixed at the upper Jiugang vacuum valve to open, closed Vacuum bottles for good treatment, Bozhuan stem from operating, open the valve of the bottle filling CO2 gases, vacuum convex .Round to open the vacuum valve, the bottle will air mixed with CO2 out of gas, open the valve again, the CO2 gas bottle filling, the filling valve on the pressure valve in the bottle close to back-pressure gas pressure at the open-Jiuye Pingbi into the bottle, through pneumatic or electrical control filling valve to achieve the filling of beer.Today's advanced international beer filling, Gland machine control system mainly by the photoelectric switch position detection part and take the bottles with, Jiugang speed part, dominated by the PLC, touch screen and other components. Filling, Gland of the mechanical structure and PLC programmable control devices, frequency stepless speed regulation, human-computer interface, and other modern means of complete automatic control technology, the combination of a mechanical and electrical integration.3. Controlled part of the programmeMany domestic beer manufacturers are now using the filling, Gland of the control system of uneven degree of automation; button and all the manual switch technology have set up operations in a box on the panel, PLC controller for the majority of Japanese companies or OMRON Mitsubishi's early products, equipment chain of control, less protection settings, plus the beer filling the scene poor environment, humidity, such as contact with the switch contacts serious corrosion, the system's signal detection of the high failure rate, resulting in equipment control system Operation of low reliability, the normal operation of equipment, such as short-cycle phenomenon.To the actual transformation of the Dandong Yalu River Brewery Co., Ltd. of filling, Gland machine control system as an example, the transformation of methods to clarify the control of such equipment thinking and ideas, according to the scene of the actual process conditions, to prepare the operation of the PLC Procedures. For beer filling, Gland control system of the actual situation and in accordance with the actual process conditions at the scene, re-design of the equipment of the PLC control system. This transformation of the same methods and ideas can be applied to other liquids and the transformation of filling equipment. 3.1 system hardware configurationJapan's Mitsubishi Corporation to use the FX2N128MRPLC use the system to replace the original 2-OMRON's C60P PLC, the original system of the PLC is due to old models, and computer on-line communications need to configure special converters, the system need to increase the external I / O input points , The extension of spare parts more difficult to find. FX2N128MRPLC is an integrated 128-point I / O controller of the box, a computing speed, command rich, high-cost performance, on-line programming simple and easy extension of the advantages of the Mitsubishi FX series, features the strongest small controller .(1) by the Mitsubishi 900 series of 970 GOT human-computer touch screen system to replace the original use of the button panel display equipment and monitor the operation of operating parameters. 970GOT HMI for the 16-color high-brightness significantly, through the convergence of connectivity and FX2N128MRPLC directly connected to the CPU, achieving rapid response. Has many maintenance features, such as the list-editing features, ladder monitoring (troubleshooting) function, the system monitoring functions to find fault and maintenanceof PLC Systems.(2) filling, Gland of the frequency converter in the transformation of no replacement, on-site detection signal means-testing is still used switch, switch for detecting long-term work in the humidity of the great occasions, the choice of capacitive proximity switches, according to PLC I / O terminal of the connection mode, select the type of close PNP switch, the control system of Figure 1. 3.2 Systems Programming PLC controller programming focus and the core is around Jiugang the rotation speed control and Jiugang on 60 bottles of detecting the location of the displaced, broken bottles, empty bottles at the location of testing and related displacement filling Such as control valves. The bottles displacement of testing procedures, using a Mitsubishi PLC in the left command.Figure 1 control system structure diagram .Bottles displacement of detection, using the left-PLC command, which commands the whole of one of the core control procedures, the main electrical switch detection and bottles at the bottle simultaneously detect mobile, the main motor to every week, just to the corresponding Jiugang Have a bottle of, PLC unit within the internal correspondence that 60 bottles of the unit for the M500 ~ M559, the number of units by the first letter K is set to K60, with each change in a second letter K is set to K1, M50 Reaction of the empty bottles in the short position, and detect the location of the motor speed to go on the frequency shift in the corresponding unit within the built-in "1" or "0", control valves and the corresponding mixing caps The motor stopped and opened. Continuous detection system in place after the 90 empty bottles, stop stirring caps the motor running, testing the number of bottles in accordance with the user's requirements canbe arbitrary.A bottle of detection. Rotary Jiugang through pressure to back pressure with the bottle of liquor in the process of empty bottles in the back-pressure, because the bottle itself may crack and other reasons leading to a sudden burst bottles, which need to detect the location of unexploded bottle bottle, in this bottle - The position opened purge solenoid valves, compressed air out, broken bottles at the bottle-blowing from the position in a row after the purge and several bottles of the electromagnetic valve open jet, a high-pressure spray Shuizhu, in the break Bottle position around a few bottles of spray bottles in a row.Detection of broken bottles and bottle-detection switch simultaneously detect movement of breaking bottles, to the main motor of each week, precisely corresponding Jiugang passed a bottle of, PLC unit within the internal correspondence that 20 broken bottles at the unit for the M600 ~ M619, unit With the number of the first letter K is set to K20, with each change in a second letter K is set to K1, M52 response to the location of the broken bottles and detected the location of the motor speed to the frequency shift continue, In the corresponding unit within the built-in "1" or "0", control and the corresponding jet purge solenoid valve opened and stopped. Continuous Spray and purge solenoid valve open to listen, time stopped in accordance with technological requirements can be arbitrary.System security is to control access to the caps simultaneously tracking, not only accurately detect the electrical switching speed detection, the broken bottles into the bottle and detection switch detection switch three conditions.970GOT human-computer touch-screen terminals operated by the software company's Mitsubishi GT WORKS package, whichis a GT Designer with the entire GOT9000 series of graphics software packages. The package is simple, prior to a personal computer simulation on the configuration and debug, after the man-machine operators to download terminals. At the same time, because the man-machine interface and a touch-screen role, will set common switch on the screen to facilitate the operation. And also to increase the number of features, such as setting alarm information. 4.After transformation control systemSystem at the normal operation of the machine for automatic control, in accordance with bottles into and out of the bottle for lack or slow pace set by running into the bottle stall bottles, no less than a bottle cap, automatic washing bottles burst, filling automatic back-pressure position , Covered under the system automatically lose covered a stop and safety protection, such as the coordination of action interlock. All the original button after the operation of the touch screen on. 5.Detection of the state control system monitoringDetection switch into the bottle and break bottles detection switch bottles of pressure by testing each part of the small metal plates above the location of a photoelectric pulse output, a further PLC acquisition, as each bottle of the pressure above the small metal plates is the location of activities , In the machine running after some time, some pressure above the small bottles of iron tablets and detection switch in the location of displacement, resulting in detection switch mistaken judgement, if not for the judgement of bottles of bottles, bottle explosion Lou Jian, misuse, such as the seizure of output errors So that the PLC have mistaken action, such as a back-pressure, unexploded bottle blowing, washing, stirring cap control system malfunction, such as failure phenomenon.Before the transformation of the daily production process, encountered this phenomenon, the operatives could only switch to the various functional or manual control buttons reach the stall so that the equipment work in the absence of monitoring state, the machine lost control function. Caused a lot of production of raw materials such as gas, water, wine waste. Only in the production of intermittent, can be fitter and maintenance electrician in accordance with the detection of small switch on the light-emitting diodes and anti-displacement by adjusting the distance only 5 ~ 8 mm detection switch installation location, and switch to fix detection of small metal plates Gap. This means of detection is very backward, after adjustment reaction to the results, timely response can not be adjusted results.In view of this testing situation, after the transformation of the filling, Gland control system configuration, this part of a new detection and integration in human-computer touch screen, complete bottle of detection.In human-computer touch screen interface on the page display, respectively, at customs, such as electromagnetic motor mixing valve switch state are in different colors to show, very intuitive.Increase the system's functions is to ensure the irrigation of the machine-Gland normal operation of automated control system specifically designed to. 6 Concluding remarks After the transformation of the control system will greatly simplify the complicated mechanical structure, the running and control of inspection, the degree of automation systems meet the design requirements, greatly reducing the operational strength of the labor so that the shrub-like beer output than in the past Raising more than 30 percent, greatly reduce the failure rate.Embodies the modern equipment of automatic control technology. In the digestion and absorption of today's industrial control on the basis of advanced technology innovation, development of domestic technology from the most advanced filling control system.啤酒灌装、压盖机PLC控制系统1、引言啤酒生产过程分为麦芽制造、麦芽汁制造、前发酵、后发酵、过滤灭菌、包装等几道工序。

关于PLC的外文及翻译

PLCs --Past, Present and FutureEveryone knows there's only one constant in the technology world, and that's change. This is especially evident in the evolution of Programmable Logic Controllers (PLC) and their varied applications. From their introduction more than 30 years ago, PLCs have become the cornerstone of hundreds of thousands of control systems in a wide range of industries.At heart, the PLC is an industrialized computer programmed with highly specialized languages, and it continues to benefit from technological advances in the computer and information technology worlds. The most prominent of which is miniaturization and communications.The Shrinking PLCWhen the PLC was first introduced, its size was a major improvement - relative to the hundreds of hard-wired relays and timers it replaced. A typical unit housing a CPU and I/O was roughly the size of a 19 television set. Through the 1980s and early 1990s, modular PLCs continued to shrink in footprint while increasing in capabilities and performance (see Diagram 1 for typical modular PLC configuration).In recent years, smaller PLCs have been introduced in the nano and micro classes that offer features previously found only in larger PLCs. This has made specifying a larger PLC just for additional features or performance, and not increased I/O count, unnecessary, as even those in the nano class are capable of Ethernet communication, motion control, on-board PID with autotune, remote connectivity and more.PLCs are also now well-equipped to replace stand-alone process controllers in many applications, due to their ability to perform functions of motion control, data acquisition, RTU (remote telemetry unit) and even some integrated HMI (human machine interface) functions. Previously, these functions often required their own purpose-built controllers and software, plus a separate PLC for the discrete control and interlocking.The Great CommunicatorPossibly the most significant change in recent years lies in the communications arena. In the 1970s Modicon introduction of Modbus communications protocol allowed PLCs to communicate over standard cabling. This translates to an ability to place PLCs in closer proximity to real world devices and communicate back to other system controls in a main panel.In the past 30 years we have seen literally hundreds of proprietary and standard protocols developed, each with their own unique advantages.Today's PLCs have to be data compilers and information gateways. They have to interface with bar code scanners and printers, as well as temperature and analog sensors. They need multiple protocol support to be able to connect with other devices in the process. And furthermore, they need all these capabilities while remaining cost-effective and simple to program.Another primary development that has literally revolutionized the way PLCs are programmed, communicate with each other and interface with PCs for HMI, SCADA or DCS applications, came from the computing world.Use of Ethernet communications on the plant floor has doubled in the past five years. While serial communications remain popular and reliable, Ethernet is fast becoming the communications media of choice with advantages that simply can't be ignored, such as: * Network speed. * Ease of use when it comes to the setup and wiring. * Availability of off-the-shelf networking components. * Built-in communications setups.Integrated Motion ControlAnother responsibility the PLC has been tasked with is motion control. From simple open-loop to multi-axis applications, the trend has been to integrate this feature into PLC hardware and software.There are many applications that require accurate control at a fast pace, but not exact precision at blazing speeds. These are applications where the stand-alone PLC works well. Many nano and micro PLCs are available with high-speed counting capabilities and high-frequency pulse outputs built into the controller, making them a viable solution for open-loop control.The one caveat is that the controller does not know the position of the output device during the control sequence. On the other hand, its main advantage is cost. Even simple motion control had previously required an expensive option module, and at times was restricted to more sophisticated control platforms in order to meet system requirements.More sophisticated motion applications require higher-precision positioning hardware and software, and many PLCs offer high-speed option modules that interface with servo drives. Most drives today can accept traditional commands from host (PLC or PC) controls, or provide their own internal motion control. The trend here is to integrate the motion control configuration into the logic controller programming software package.Programming LanguagesA facet of the PLC that reflects both the past and the future is programming language. The IEC 61131-3 standard deals with programming languages and defines two graphical and two textual PLC programming language standards: * Ladder logic (graphical). * Function block diagram (graphical). * Structured text(textual).Instruction list (textual).This standard also defines graphical and textual sequential function chart elements to organize programs for sequential and parallel control processing. Based on the standard, many manufacturers offer at least two of these languages as options for programming their PLCs. Ironically, approximately 96 percent of PLC users recently still use ladder diagrams to construct their PLC code. It seems that ladder logic continues to be a top choice given it's performed so well for so long.Hardware PlatformsThe modern PLC has incorporated many types of Commercial off the Shelf (COTS) technology in its CPU. This latest technology gives the PLC a faster, more powerful processor with more memory at less cost. These advances have also allowed the PLC to expand its portfolio and take on new tasks like communications, data manipulation and high-speed motion without giving up the rugged and reliable performance expected from industrial control equipment.New technology has also created a category of controllers called Programmable Automation Controllers, or PACs. PACs differ from traditional PLCs in that they typically utilize open, modular architectures for both hardware and software, using de facto standards for network interfaces, languages and protocols. They could be viewed as a PC in an industrial PLC-like package.The FutureA 2005 PLC Product Focus Study from Reed Research Group pointed out factors increasingly important to users, machine builders and those making the purchasing decisions. The top picks for features of importance were.* The ability to network, and do so easily. Ethernet communications is leading the charge in this realm. Not only are new protocols surfacing, but many of the industry de facto standard serial protocols that have been used for many years are being ported to Ethernet platforms. These include Modbus (ModbusTCP), DeviceNet (Ethernet/IP) and Profibus (Profinet). Ethernet communication modules for PLCs are readily available with high-speed performance and flexible protocols. Also, many PLC CPUs are now available with Ethernet ports on board, saving I/O slot space. PLCs will continue to develop more sophisticated connectivity to report information to other PLCs, system control systems, data acquisition (SCADA) systems and enterprise resource planning (ERP) systems. Additionally, wireless communications will continue to gain popularity.* The ability to network PLC I/O connections with a PC. The same trends that have benefited PLC networking have migrated to the I/O level. Many PLC manufacturers are supporting the most accepted fieldbus networks, allowing PLC I/O to be distributed over large physical distances, or located where it was previously considered nearly impossible. This has opened the door for personal computers to interface with standard PLC I/O subsystems by using interface cards, typically supplied by the PLC manufacturer or a third party developer. Now these challenging locations can be monitored with today a PC. Where industrial-grade control engines are not required, the user can take advantage of more advanced software packages and hardware flexibility at a lower cost.* The ability to use universal programming software for multipletargets/platforms. In the past it was expected that an intelligent controller would be complex to program. That is no longer the case. Users are no longer just trained programmers, such as design engineers or systems integrators, but end-users who expect easier-to-use software in more familiar formats. The Windows-based look and feel that users are familiar with on their personal computers have become the most accepted graphical user interface. What began as simple relay logic emulation for programming PLCs has evolved into languages that use higher level function blocks that are much more intuitive to configure. PLC manufacturers are also beginning to integrate the programming of diverse functions that allow you to learn only one package in configuring logic, HMI, motion control and other specialized capabilities. Possibly the ultimate wish of the end-user would be for a software package that could seamlessly program many manufacturers PLCs and sub-systems. After all, Microsoft Windows operating system and applications work similarly whether installed on a Dell, HP or IBM computer, which makes it easier for the user.Overall, PLC users are satisfied with the products currently available, while keeping their eye on new trends and implementing them where the benefits are obvious. Typically, new installations take advantage of advancing technologies, helping them become more accepted in the industrial world.PLC的过去、现在与未来众所周知，科技世界里只有一个永恒真理，那就是变化。

PLC中英文资料外文翻译

步进电机PLC控制技术中英文对照外文翻译文献

PLC-外文文献+翻译

PLC中英文资料外文翻译

可编程控制器外文翻译、中英文翻译、外文文献翻译

(完整版)PLC英文文献+翻译

plc单片机 毕业论文文献翻译 中英文对照

PLC行业常用184个专业英语中英文词汇对照

PLC常用英文词汇（中文对译）

中英文文献翻译-关于PLC外文翻译

PLC的工作原理中英文翻译

PLC中英文资料外文翻译

可编程控制器应用中英文对照外文翻译文献

PLC及变频器技术中英文对照外文翻译文献

plc英文翻译

PLC控制系统英文文献+翻译

关于PLC的外文及翻译

plc单片机毕业论文文献翻译中英文对照