【正文】 分，因此近年來 PLC 率的上升，總是說是逐步緩慢。 在考慮幾何形狀的變化和機能力轉(zhuǎn)換特性作為制造行業(yè)，并采取物理的變化和化學的變化原料產(chǎn)品作為特色工藝行業(yè)中，此外不斷的數(shù)量由主要反應控制，特別有大規(guī)模開關量主要的環(huán)狀順序控制在制造工業(yè)中，它進行平滑移動號 （根據(jù)邏輯條件根據(jù)演替的運動 ；此外也有使用順序，繼承并不是與連鎖保護運動根據(jù)邏輯關系 進行控制 ；以及大規(guī)模的交換機數(shù)量、 動脈的沖動、 時間、 計數(shù)器，模擬量向警察和等等條件數(shù)量報告主要數(shù)據(jù)采集監(jiān)測。 Another method is provides longdistance I/O from the station and so on. These all explained the PLC factory the hardware various parts to the user development, is advantageous for the user to select, disposes scale different PLC, moreover this kind of hardware disposes openness, for the manufacturer, retails business (business agent), system integration business, the enduser brings very many convenient es for the marketing supply to be very greatly convenient, this is a big success experience. In PLC I/O template, except general DI/DO, outside AD/DA template, but also has developed a series of special functions I/O template, this was PLC uses in all the various trades and occupations to open the outlet, like used in the bar code recognition ASCII/BASIC template, used in the reaction control PID template, used in the operating control, the 無 錫 職 業(yè) 技 術(shù) 學 院 畢業(yè)設計說明書（英文翻譯） 3 machinefinishing highspeed counting template, the single axle position control template, the two axle position control template, the cam locator template, the radio frequency recognition connection template and so on, this also will be able to have the very big development in later. Moreover in the input, the output related part, the situation input, the output electricity isolation, aspect and so on isolation also can be more perfect. In PLC CPU and the memory coordination, pletes the control function. It with DCS system parameter and so on processing temperature, pressure, current capacity system different, uses the fast tour scanning cycle, generally is ~, is quicker selects 50ms or the smaller scanning cycle. It is a digital sampling control system. Central Processing Unit (CPU) is the brain of a PLC controller. CPU itself is usually one of the microcontrollers. Aforetime these were 8bit , and now these are 16and 32bitmicrocontrollers. Unspoken rule is that you’ll find mostly Hitachi and Fuji microcontrollers in PLC controllers by Japanese makers, Siemens in European controllers, and Motorola microcontrollers in American ones. CPU also takes care of munication, interconnectedness among other parts of PLC controllers, program execution, memory operation, overseeing input and setting up of an output. PLC controllers have plex routines for memory checkup in order to ensure that PLC memory was not damaged (memory checkup is done for safety reasons).Generally speaking, CPU unit makes a great number of checkups of the PLC controller itself so eventual errors would be discovered early. You can simply look at any PLC controller and see that there are several indicators in the form. of light diodes for error signalization. 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 forma 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 puter (usual way), but also through manual programmers (consoles). This practically means that each PLC controller can programmed through a puter if you have the software needed for programming. Today’s transmission puters 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 munication works 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 ments that can be useful when finding errors, or with system maintenance. Adding ments and remarks enables any technician (and not just a person who developed the system) to understand