Design and Realization of Portable Water Quality PH Detector

Abstract

At present, many PH value measuring instruments on the market have many problems, for example, the measurement accuracy is not high enough, the circuit wiring is too complicated, and the stability is not strong. Therefore, in order to improve the measurement accuracy of the detector, reduce the effect of temperature on the pH measurement of the solution, simplify the circuit layout, and enhance the stability of the measurement circuit, Developed a STC89C52 microcontroller as the core processor, using Raycore E-201-CPH composite electrode to collect analog voltage signal and transfer it to A/D converter to convert into digital signal after amplified by op amp, and input it into the single-chip microcomputer together with the digital signal collected by the temperature sensor. Finally, after processing by the SCM, it is transmitted to the LCD1602 liquid crystal display module, showing the measured pH value and temperature value. The whole design is made down, and after many debugging, it can be concluded that the PH detector can accurately detect the PH value of the solution. It also has the characteristics of cheaper, affordable, high precision, good stability, simple circuit, simple operation and so on, which is suitable for the needs of most of the current users.