中国地质大学长城学院毕业论文外文资料翻译(3)

This article main discussion studies uses Simens in the S7-200 PLC to carry on the control to elevator's fluctuation, forms the lift control system.

PLC Introduction Programmable controller is the first in the late 1960s in the United States, then called Plc programmable logic controller (ProgrammableLogicController) is used

to replace relays. For the implementation of the logical judgement, 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) judgement functions also have data processing, PID conditioning and data communications functions. International Electrotechnical 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; ④ functional improvements, strong functional interface

PLC language is not we imagine of edit collected materials the language or language of Cs to cany on weaving the distance, but 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,butthe exportation equipments direct conjuuctiou 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 |10s 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. 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.

Application of PLC in the Elevator Control System of

Intelligence Building

In 1980s the first intelligence mansion had been completed in America, then intelligence building has been a broadly taken attentions by the whole world. The concept of intelligence building has been put different meanings along with the development of society. The early stage intelligence building had been thought that it is equal to the intelligence mansion, but now the intelligence building not only includes the intelligence mansions but also involves intelligence residential districts. This paper mainly discusses one subsystem of intelligence building system: the elevator control system.

In intelligence residential districts the enterprise’s information managing system mainly takes charge of the things which related to the daily life, for example supervising the district equipments, managing vehicles, disposing critical situations and so on.The elevator supervising and control system is also necessary to the intelligen …… 此处隐藏：6117字，全部文档内容请下载后查看。喜欢就下载吧 ……