In the air-conditioning laboratory, when measuring the cooling capacity (or heating capacity) of the water side of the water machine, the inlet and outlet water temperature and water flow rate of the prototype are usually measured, and then the cooling capacity (or heating capacity) is calculated. The water flow here is basically measured with an electromagnetic flow meter.

The English name of flowmeter is flowmeter, which is defined by the national science and technology terminology Approval Committee as an instrument indicating the measured flow and / or the total amount of fluid within the selected time interval.