Objective

• It is used in the agriculture industry to determine the pH of solid. 

• It’s also used to test the quality of municipal drinking water and swimming pools. 

• It is used to measure the pH value of solutions in numerous chemical and pharmaceutical businesses. 

• The pH meter is also used in the food business, particularly for dairy products such as cheese, curds, and yoghurts. 

Operating Mechanism

• A sample is placed in a cup and the glass probe at the end of the retractable arm is placed in it. Probe is connected to the main box. There are two electrodes inside the probe that measure voltage. One is contained in liquid with fixed pH. Other measure the acidity of the sample through the amount of H+ ions. 

• A voltmeter in the probe measures the difference between the voltages of the two electrodes. The meter than translates the voltages difference into pH and displays in on the screen. Before taking a pH measurement the meter must be calibrated using a solution of known pH.