pH meter, conductivity meter and Dissolved Oxygen Meter are instruments used to measure different water quality parameters, and they have obvious differences in measurement objects, working principles and application fields.
A pH meter is an instrument used to measure the acid-base properties of a solution. It determines the pH value of the solution by measuring the potential difference of the solution based on the relationship between the glass electrode and the concentration of hydrogen ions in the solution. pH meters are widely used in environmental monitoring, water quality analysis, biological science, chemical experiments and other fields to measure the pH of the solution and judge the degree of acidity or alkalinity of the solution.

Conductivity meters are used to measure the conductivity of ions in liquids (aqueous solutions) or solutions. It measures the conductivity of ions in a solution to current and converts it into conductivity values. Conductivity meters are widely used in water quality analysis, environmental monitoring, industrial process control and other fields to evaluate the ionic concentration, purity, dissolved substance content and other indicators of solutions.

Dissolved Oxygen Meters are used to measure the content of dissolved oxygen in water. It is based on the redox reaction between the oxygen electrode and the dissolved oxygen in the solution, and the concentration of dissolved oxygen in the solution is determined by measuring the potential difference. Dissolved Oxygen Meters are widely used in water quality monitoring, water treatment, aquaculture and other fields to evaluate the content of dissolved oxygen in water, and judge the redox state and water quality of water.

To sum up, pH meters are used to measure acid-base properties, conductivity meters are used to measure ion conductivity, and Dissolved Oxygen Meters are used to measure dissolved oxygen content. There are differences in measurement principles, application fields and measurement objects, and they are suitable for different water quality parameter analysis and monitoring needs.