The P2546A, manufactured by WINDSENSOR, is a Class 1 anemometer often used for wind speed resource assessment and wind turbine power performance monitoring. Wind speed is sensed by a three-cup rotor assembly. Magnets mounted on the shaft cause a switch to close and open two times per revolution. Our data loggers measure the switch closure and convert the signal to engineering units (mph, m/s, knots). The anemometer is mounted using the 27739 30-inch mounting pole. The P2546A comes with a MEASNET calibration certificate. The P2546C (coil version) and P2546D (electronic version) are also available. Note: The P2546A, which includes a mercury reed switch and is not CE- or RoHS-compliant, has been replaced for most applications by the P2546D.