The Hardware Design of Acid Rain Observing Instrument

摘要

The acid rain observation system usually includes the measurements and analysis of pH value and electric conductivity and temperature compensation should be taken into consideration as pH value and electric conductivity of acid rain measured.The measuring principles of pH value and electric conductivity are discussed in the paper.An acid rain observing instrument is developed,which uses a single chip microcomputer as control core,and pH composite glass electrode,platinum black electric conductivity electrode and platinum resistance PtlOO as sensitive devices.It not only has high measuring accuracies by using the AD7792 as analog-digital conversion chip,but also has advantages in low cost,small volume and low power consumption.The tests indicate that the acid rain observing instrument services high measuring accuracies for the pH value and electric conductivity of acid rain and provides important reference information for environmental monitoring.