Selecting an Anemometer on Amazon.com
An anemometer, also known as a wind meter or wind speed meter, measures the velocity of air. Depending on its complexity, an anemometer may also measure properties such as wind direction, air pressure, air flow volume, air temperature, humidity, and light. Anemometers are most often used to measure wind speed in weather monitoring and to measure air flow within ducts in HVAC (heating, ventilation, and air conditioning) applications. They are also used to survey for wind turbine placement, to monitor ventilation in spray booths and exhaust hoods, and to track air velocity in wind tunnel testing.
These instruments range from basic cup anemometers, which require manual counting of the cup rotation, to digital hot-wire anemometers with multi-function capabilities. For cup and vane anemometers, air velocity is determined by the number of rotations of the cups or vane. A vane anemometer is also known as a windmill or propeller anemometer. As air cools the heated wire in a hot-wire anemometer, the change in electrical resistance is measured to determine air velocity. It is generally more accurate than a cup or vane type, making it suitable for testing in laboratories. A handheld anemometer is usually a vane or hot-wire type instrument designed for portability, and often has a probe for reaching into ductwork. A Pitot tube anemometer calculates air velocity by determining the difference in air pressure inside and outside the tube.
Anemometers with a digital readout may have a built-in data logger to record readings, an output for transferring data to a computer, and functions such as average, minimum, maximum, and hold. They may also show readings of air velocity in different units of measure, such as meters per second (m/s), feet per minute (ft./min. or FPM), knots, miles per hour (mph), and kilometers per hour (km/h).
An anemometer that measures air pressure as well as air velocity can be designated as an anemometer-manometer. Manometers can typically measure very low pressures, such as static and differential pressure, and that pressure reading can be converted into air velocity and air flow volume measurements.