The Dwyer Durablock series 400 air velocity meter kit includes a dual-scale, solid acrylic anemometer and manometer gauge with an 18" Pitot tube and accessories for measuring air velocity in fpm, and static and differential pressure in inches of w.c., and features an adjustment screw and built-in spirit level vial to maintain horizontal plane for accurate readings. Precision machined from solid acrylic to maintain calibration, resist breakage, and provide a clear view of the scale, the gauge has an inclined section for accurate readings and a vertical section for an extended range of measurement. The Pitot tube is made of stainless steel to resist corrosion and withstand temperatures up to 1,500 degrees F, and is graduated in inches for determining insertion depth when conducting duct traverse measurements. The scale has red markings for velocity readings and black markings for pressure readings and uses red gauge fluid for distinct readings. The gauge is rated for total pressure to 100 psig (6.89 bar) and temperatures to 65.6 degrees C (150 degrees F). Kit includes an anemometer and manometer gauge, a Pitot tube, two lengths of 3/16" diameter rubber tubing with metal terminals, a magnetic clip for mounting on metal surfaces, a bottle of red gauge fluid, an air velocity slide rule calculator, a steel carrying case with a foam insert to hold the gauge and accessories, and instructions. This anemometer and manometer is used for monitoring air flow in ducts, balancing air conditioning systems, and measuring fan and blower pressures, furnace drafts, and pressure drops across air filters, among other applications.

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).

Dwyer Instruments manufactures measurement and control instruments, including pressure gauges, flow meters, level instrumentation, temperature instrumentation, and air quality monitors. The company, founded in 1931, is headquartered in Michigan City, IN.

What's in the Box?

• Dwyer Durablock series 400 anemometer and manometer gauge
• 18" stainless steel Pitot tube
• (2) lengths of 3/16" diameter rubber tubing with metal terminals
• Magnetic mounting clip
• Bottle of red gauge fluid
• Air velocity slide rule calculator
• Steel carrying case
• Instructions