基于PLC的液位控制系统方案设计书.docVIP

电信学院毕业设计任务书 题目 基于PLC的污水池液位控制系统设计 学生姓名 班级 学号 题目类型 工程设计 指导教师 魏祥林 系主任 一、毕业设计（论文）的技术背景和设计依据： 与传统的人工调节相比液位自动控制系统节能效果显著人工劳动强度，。 二、毕业设计（论文）的任务 1、熟悉题目要求，查阅相关科技文献，写出开题报告； 2、方案设计（包括方案论证与确定、技术经济分析等内容）； 3、硬件系统设计； 4、软件系统设计； 6、撰写设计说明书，绘制图纸； 6、翻译一篇与自己所学专业或设计有关的英文资料； 三、毕业设计（论文）的主要内容、功能及技术指标： 1、系统要求用户能够直观地了解现场设备地工作状况及水位的变化； 2、要求用户能够远程控制变频器的启动和停止； 3、用户可以自行设置水位的高、低，以及控制变频器的启、停； 4、变频器及其他设备的故障信息能够及时反映在远程单片机上； 5、具有水位过高、过低报警和提示用户功能。 6、专业英文文献翻译； PLCs --Past, Present and Future Everyone knows theres only one constant in the technology world, and thats 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 PLC When 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,