The Research And Design Of Environmental Water Quality Detecting Meter

With the rapid development of our country's economy and the acceleration of industrialization and urbanization, water pollution becomes increasingly serious and blocks national economic development and ecological environment harmonious development. Water environment management and control not only need perfect relevant laws and regulations but also need to develop water quality detecting equipment used as important means of protecting water environment and control water pollution. Water quality detection can accurately reflect the situation of water quality, forecast development trend of water quality, provide scientific basis for the protection, development and utilization of water resources and prevention and control of water pollution and has practical guiding significance for our country's dispose of water pollution problems.Using low power consumption MCU MSP430F5529 as the control core, environmental water quality detecting meter designed in this thesis can detect five routine water quality parameters including water temperature, PH value, dissolved oxygen, turbidity and conductivity. The thesis analyzes the domestic and overseas development status of water quality detecting meter, studies the detecting principle of each parameter, selects the appropriate detecting methods and designs the corresponding acquisition and conditioning circuit according to the characteristics of each parameter electrode. In addition, the power circuit, display circuit, keyboard interface circuit and RS-232 interface circuit have been designed so as to realize the real-time display and transmission of testing data. Software design includes lower computer programmed by using C language and upper computer programmed by using MFC. In order to reduce the effects of temperature on the accuracy, temperature compensation for PH value, conductivity and dissolved oxygen has been completed by using software programming method; conductivity detecting circuit adopts automatic gears selection methods to improve the accuracy of measurement.Verification results show that this system can realize the detection of five routine water quality parameters, accuracy of water temperature, PH value and conductivity is basically accurate and meets the requirements of the system design.