Description

A pH meter is a scientific instrument that measures the activity of hydrogen ions in water-based solutions, indicating its acidity or alkalinity expressed as pH. It consists of two basic elements :

1- A high input impedance meter This is the main body, which houses the microchip used to process minute electrode voltages and display measurements in pH units on a display.

2- The probe or the combined electrode : made up of 2 electrodes, this is the part where the measurement actually takes place. The probe is the consumable, sensitive and most expensive part of the meter; and should be handled with care. The combination electrode consists of a measuring electrode (glass electrode) and a reference electrode, both immersed in the same solution. In order to obtain a defined pH value, the reference electrode must have a defined stable potential which is independent of the measured solution.