Campbell Scientific WXT510 Weather Transmitter - Manual (Page 5)

WXT510 Weather Transmitter
1. General Description
The WXT510 Weather Transmitter, manufactured by Vaisala, measures wind
speed and direction, precipitation, barometric pressure, temperature, and
relative humidity—all in a single device that has no moving parts. The
WXT510’s SDI-12 signal can be measured by any of our SDI-12 equipped
dataloggers. The WXT510 is about the size of our larger Gill radiation shield,
making it ideal for use with our CR200-series dataloggers in applications
requiring quick, short-term deployment. However, the WXT510 is not
intended for weather stations that require research-grade performance.
1.1 Wind Speed and Direction
The WXT510's wind sensor consists of three equally spaced transducers that
produce ultrasonic signals. Wind speed and direction are determined by
measuring the time it takes for the ultrasonic signal of one transducer to travel
to the other transducers. Wind direction is not calculated when the wind speed
drops below 0.05 m/s. In this case, the last calculated direction output remains
until wind speed increases. The computed wind speeds are independent of
altitude, temperature, and humidity. The WXT510 is preconfigured to provide
the minimum, average, and maximum values for both wind speed and
direction. Default wind speed units are m/s.
1.2 Precipitation
The WXT510 uses the RAINCAP® Sensor to measure accumulated rainfall,
rain intensity, and rain duration. Precipitation is measured one raindrop at a
time. Whenever a raindrop hits the precipitation sensor, an electrical signal is
produced that is proportional to the volume of the drop.
The sensor is also capable of distinguishing hail stones from raindrops. The
measured rain and hail parameters are cumulative amounts of rain or hail, rain
or hail intensity, and the duration of a shower.
1.3 Barometric Pressure, Temperature, and Relative Humidity
The WXT510 has a PTU module that contains a capacitive silicon
BAROCAP® sensor for barometric pressure measurements, a capacitive
ceramic THERMOCAP® sensor for air temperature measurements, and a
capacitive thin film polymer HUMICAP® sensor for relative humidity
measurements. The PTU is housed in a naturally aspirated radiation shield that
protects the PTU and reflects solar radiation. Default units are °Celsius for
temperature and hPa for barometric pressure.
2. Specifications
2.1 Wind Speed
Measurement Range: 0 to 60 m s -1
Accuracy: ±0.3 m s
-1
or ±3% whichever is greater (0 to 35 m s
-1
);
±5% (36 to 60 m s
-1
)
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