Thermal mass flow meters for compressed air are flexible instruments that can also measure the flow of many other gases. Their working principle is based on heat transfer. A heated sensor loses heat to the passing gas and this cooling effect is proportional to the mass flow. By monitoring the temperature change, the meter determines the actual gas flow.

Because each gas has its own thermal conductivity and molecular properties, modern instruments use software algorithms to adjust these factors. A sensor calibrated in air can therefore be adapted to nitrogen, oxygen, carbon dioxide or other compressed gases by applying the correct gas settings.

This makes thermal mass flow meters a reliable choice for a wide range of gas applications where accurate mass flow measurement is needed.