The Testo 405 anemometer with telescoping hot-wire probe reaches into ducts to measure air velocity in m/s, air flow volume in m3/h, and air temperature in degrees C; swivels for viewing readings at any angle; and has one-button operation for ease of use. A cap over sensor can be twisted open for measurements and closed to protect against dirt and moisture. The meter turns off automatically after five minutes of non-use to conserve battery life. This anemometer is used for monitoring air flow and temperature in ductwork, spray booths, and exhaust hoods, among other applications.
H is height, the vertical distance from the lowest to highest point; W is width, the horizontal distance from left to right; D is depth, the horizontal distance from front to back.
Anemometers, also called wind meters, measure air velocity and are most commonly used for weather monitoring to determine wind speed and for HVAC applications to determine air flow within ducts. In addition to air velocity, anemometers may measure wind direction, air pressure, air flow volume, air temperature, humidity, light, and other properties. The most common types of anemometer are cup, vane, hot-wire, and Pitot tube. Cup and vane anemometers calculate air velocity based on the number of rotations of the cups or vane. Hot-wire anemometers calculate air velocity by measuring the change in electrical resistance as air flow cools a heated wire. Pitot tube anemometers measure air pressure within a tube and calculate air velocity based on the difference in pressure between the air inside and outside of the tube. Many anemometers have digital readouts and can display air velocity readings 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).
Testo manufactures portable test and measurement instruments. The company, founded in 1957 in Germany, has a U.S. office in Sparta, NJ, and meets International Organization for Standardization (ISO) standard 9001.