The anemometer has three hemispherical molded plastic cups. Cup wheel rotation produces an AC sine wave voltage signal with frequency directly proportional to wind speed. This AC voltage signal is induced in a coil by a two pole circular magnet mounted on the cup wheel shaft. One complete sine wave cycle is produced for each cup wheel revolution.

Wind vane position is transmitted by a 10k ohm precision conductive plastic potentiometer which requires a regulated excitation voltage. With a constant voltage applied to the potentiometer, the output signal is an analog voltage directly proportional to azimuth angle. The plastic vane is molded directly on the anodized aluminum vane shaft.


Specifications

Range

    Wind speed: 0-50 m/s (112 mph)
    Gust survival: 60 m/s (134 mph)
    Azimuth: 360° mechanical, 355° electrical (5° open)

Threshold*

    Cup Anemometer: 1.1 m/s (2.5 mph)
    Vane: 1.3 m/s (2.9 mph) at 10° displacement
    1.9 m/s (4.2 mph) at 5° displacement
    *Nominal values - determined in accordance with ASTM standard procedures

Dynamic Response

    Cup wheel distance constant: 2.3 m (7.5 ft)
    Vane delay distance: 0.5 m (1.6 ft)
    Damping ratio: 0.20

Signal Output

    Wind speed: Magnetically induced AC sine wave voltage, 1 pulse per revolution, 1800 rpm (30 Hz) = 22.8 m/s (51.0 mph)
    Azimuth: Analog DC voltage from conductive plastic potentiometer - resistance 10k, linearity 0.5%, life expectancy 20 million revolutions.

Power Required

    Potentiometer excitation: Regulated voltage recommended, 5-15 Vdc
    Sensor interface: 5-15 Vdc unregulated
    Line driver: 12-30 Vdc unregulated (depending upon line and load resistance)

Dimensions

    Overall height: 32 cm (12.6)
    Crossarm length: 28 cm (11") between instrument centers
    Vane length: 22 cm (8.7")
    Cup wheel: 12 cm (4.7") dia
    Mounting: 34 mm (1.34") dia (standard 1" pipe)

Weight

    Sensors: 0.7 kg (1.5 lbs)
    Shipping: 1.3 kg (3 lbs)

*Specify wind speed scaling

    0-50 m/s Add suffix "M"
    0-100 mph Add suffix "P"
    0-100 knots Add suffix "N"
    0-200 km/hr Add suffix "K"