Brand:NANBEI Model:PH400F Benchtop pH Meter Application:PH meter refers to an instrument used to measure the pH value of a solution. The pH meter works on the principle of a galvanic battery. The electromotive force between the two electrodes of the galvanic battery is based on Nernst's law, which is not only related to the properties of the electrodes, but also to the concentration of hydrogen ions in the solution. There is a corresponding relationship between the electromotive force of the primary cell and the hydrogen ion concentration, and the negative logarithm of the hydrogen ion concentration is the pH value. pH meter is a common analytical instrument widely used in agriculture, environmental protection and industry. Soil pH is one of the most important basic properties of soil. Factors such as temperature and ionic strength of the solution to be measured should be considered in the pH measurement process.