可编程序控制器---PLC污水处理文献翻译.doc

南 昌 工 程 学 院 07 级毕业（设计）论文文献翻译 机械与电气工程 系（院） 电气工程及其自动化 专业 题 目 基于PLC污水处理控制系统 班 级 电气工程及其自动化（1）班 学 号 指 导 教 师 日 期 2011 年 01 月 06 日 南 昌 工 程 学 院 教 务 处 订 制  评语： 指导教师： 年 月 日 PLC Abstract: As a kind of industrial equipment powerhouses, with its straightaway programming and its stable job performance in bad environment, PLC won the general customers. PLC has been widely used in industrial areas, including machinery manufacturing, transportation system, and chemical process equipment, such as many other fields. Although computer control technology has created, its high performance and low cost, and the bad environment have strong adaptability, so PLC control is widely used in industrial control. Keywords: Programmable Logic Controller (PLC) software 1. The development of PLC Programmable controller appeared in the late 1960s in the United States, and the PLC (Programmable Logic Controller) is used to replace relays. For the implementation of the logical judgment, timing, sequence number, and other control functions. The concept of PLC is presented by General Motors Corporation. The basic design of PLC is those overalls combined the computer functional improvements, such as flexible, generic, relay control system simple and easy to operate, and with the advantages of cheap prices combined controller hardware. According to the practical application of target software, the content writes to the user procedures memory controller. The controller can be connected easily with 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