Yesterday we talked about how Oklahoma City installed a network of 40 automated environmental monitoring stations across their area called the Oklahoma City Micronet. Today we’ll take a more detailed look at the micro weather stations. The Vaisala Weather Transmitter WXT520 is a micro weather station that measures wind speed and direction, liquid precipitation, barometric pressure, temperature and relative humidity. This compact and lightweight multi-sensor instrument can measure all of these parameters in one transmitter.
This is a fairly amazing device and with no moving parts, it can accurately measure both wind speed and direction by using the advanced Vaisala WINDCAP Sensor. The sensor uses ultrasound to determine horizontal wind speed and direction. Its design ensures accurate wind measurement from all directions. The range for wind speed is from 0-134 mph and for wind direction from 0-360 degrees.
Precipitation is measured using the Vaisala RAINCAP Sensor which gives detailed information. It’s pretty cool that it can detect the individual raindrops and based on the impact of the drops determine the volume. It measures accumulated rainfall, intensity and duration in real time. However, due to the measurement method, flooding, clogging as well as wetting and evaporation losses in rain measurement are eliminated.
Barometric pressure is measured using the silicon-based Vaisala BAROCAP Senor. The sensor has minimal hysteresis and excellent repeatability, as well as outstanding temperature and long-term stability. The measurement range for pressure is from 600 to 1100 hPa.
Temperature measurement is based on the ceramic Vaisala THERMOCAP Sensor. The measurement range is from -61.6 to 140 F.
Humidity measurement is based on the Vaisala HUMICAP technology. The Vaisala HUMICAP Sensor is highly accurate and it offers excellent long-term stability in a wide range of environments and negligible hysteresis. The measurement range for humidity is 0-100 %RH.
Solar-powered Vaisala WXT520. Image: Harvest Industrial Weather Station
In order to make sure that all measurements are accurate and stable, there is a specifically designed radiation shield that it is mounted on that protects the sensors from both scattered and direction solar radiation and precipitation. The plastic material in the plates offers excellent thermal characteristics and UV stabilized construction. The white outer surface reflects radiation, while the black inside absorbs accumulated heat.
For more information on the accuracy, response time and output resolution of the Vaisala WXT520, visit www.vaisala.com