水质检测仪的设计

水质检测仪的设计(任务书,开题报告,论文17000字)
摘要
总体溶解性固体物质（Total dissolved solids，简写TDS）含量能够体现出水体的硬度等状况，是反映水质状况的一个重要参考指标，在生态环境保护、水文监测、工业生产、医疗卫生领域都具有重要的意义。自改革开放以来，我国经济发展建设日新月异，居民对于水质的重视程度也越来越高。因此，设计一个适合家庭使用的用来测量TDS值的检测仪来方便人们衡量水质显得十分有必要。
本文设计的TDS值水质检测仪，以STC90C51为芯片为处理核心，采用NE555芯片构成测量电路，以DS18B20温度传感器为核心构成的电路测量温度。该系统通过测量水的电导率，配合温度补偿计算公式，从而计算出该水在25℃下的TDS含量，在数码管上显示出来，并通过NRF24L01+无线通信模块把测量结果发送到PC端。系统还拥有由LED构成的报警电路和由DS1302组成的时钟电路。该检测仪能够实时反馈数据，使用时可以将测量部分放入家庭水箱或者水池中从而随时获得相关数据。
经过实际测试，该水质检测仪能够比较理想地完成水TDS值的量，能够实现温度补偿，并且具有超标时报警、无线通信、数码管显示的功能，同时还能够记录时间，能够满足日常生活需要。
关键词：电导率  监测温度补偿无线通信
     
The Design and Realization of Water Quality Detector
Abstract
The content of total dissolved solids(TDS) is an important parameter which can reflect the quality of water.It is used widely in environment protection,hydrological monitoring, industrial production, medical treatment and health care. With the rapid development of economy in China since Chinese economic reform, people who live in city care more and more about the quality of water. Therefore, it is necessary to design a detector for home use which can detect the value of TDS so that people can judge the quality of water according to the value the system detected.
In this thesis,we designed a water quality detector.it choose STC90C51 as the core of data processing.The measurement circuit is based on NE555.it use DS18B20 sensor to measure the temperature of water.The system can calculate the value of TDS of water which is under 25℃ by measuring the conductivity and temperature of water.The value of TDS of water will be shown on the nixietube and be transferred to PC by the module of wireless communication which is based on the chip of NRF24L01+.The system also has the clock circuit based on DS1302 and the alarm circuit made up of LED.The system is a real-time monitoring system.The detect module can be placed in the tank so that the system could feed back the information about the quality of water.
According to the result of test,the system can realize the function that measure the value of TDS of water andtemperature compensation well.it can give an alarm when the value higher than the presetvalue.The value measured by the system will be shown on the nixietube and be transferred to the computer by the module of wireless communication.it also can record the time when detecting.The function of the system can fulfill the requirements of our daily life.
Key Words:conductivity  monitor  temperature compensation  wireless communication
 

目录
摘要    Ⅰ
Abstract    Ⅱ
第一章绪论    1
1.1    课题背景    1
1.2    TDS值基本知识概述    2
1.3    TDS值基本测量知识概述    2
1.3.1    电导率基本知识概述    2
1.3.2    TDS值与电导率之间的关系    2
1.3.3    影响电导率测量精度的因素    3
1.4    几种常用水质电导率测量方法    4
1.5  本课题主要完成的任务    7
第二章水质检测仪硬件设计方案    9
2.1  整体方案设计    9
2.2  微控制器选型    10
2.3  测量电路设计    11
2.4  温度测量电路设计    12
2.5  报警电路设计    13
2.6  无线通信模块设计    13
2.7  时钟电路设计    15
2.8  辅助电路    16
第三章水质检测仪软件设计方案    18
3.1  数字频率计程序设计    18
3.2  温度测量程序    19
3.3  无线通信模块程序    21
3.4  TDS值计算程序    23
3.5  时钟功能程序    23
3.6  显示功能程序    24
第四章水质检测仪的标定、测试与运行    26
4.1  温度检测模块标定    26
4.2  TDS值与电导转换关系标定    27
4.3  温度补偿部分的标定    29
4.4  整个系统误差的标定    29
第五章总结与展望    33
5.1  总结    33
5.2  展望    33
参考文献    35
附录    37
致谢    39