User's Manual

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y Wind Speed Calibration (default is 1.0, adjustment rang 0.75 to 1.25)
y Rainfall data Calibration (default is 1.0, adjustment rang 0.75 to 1.25)
y History rainfall Calibration
y Outdoor humidity Calibration
y Outdoor temperature Calibration
y Indoor humidity Calibration
y Indoor temperature Calibration
Wind Speed Calibration
Wind speed is the most sensitive to installation constraints. The weather station should not be located
close to buildings, trees or other obstructions.
Many installations are not perfect and installing the weather station on a roof can be difficult. Thus, you
can calibrate for this error with a wind speed multiplier.
In addition to the installation challenges, wind cup bearings (moving parts) wear over time.
Without a calibrated source, wind speed can be difficult to measure. We recommend using a calibrated
wind meter and a constant speed, high speed fan.
Temperature Calibration
Temperature errors can occur when a sensor is placed too close to a heat source (such as a building
structure, the ground and when placed in direct sunlight without proper shielding in hot weather
environments).
To calibrate temperature, we recommend a mercury or red spirit (fluid) thermometer. Bi-metal (dial) and
other digital thermometers are not a good source and have their own margin of error. Using a local
weather station in your area is also a poor source due to changes in location, timing (airport weather
stations are only updated once per hour) and possible calibration errors (many official weather stations
are not properly installed and calibrated).
Place the sensor in a shaded, controlled environment next to the fluid thermometer, and allow the sensor
to stabilize for 48 hours. Compare this temperature to the fluid thermometer and adjust the console to
match the fluid thermometer.
Humidity Calibration
Humidity is a difficult parameter to measure accurately and drifts over time. Humidity errors can occur
when placed too close to the ground, near grass or other sources of humidity.
The hygrometer sensor utilizes a capacitor, which varies as a function of humidity. Due to manufacturing
tolerances, the accuracy of the sensor is ± 5%. To improve on this accuracy, the indoor and outdoor
humidity readings can be adjusted or calibrated from the display console.
To calibrate humidity, you will need an accurate source, such as a sling psychrometer or Humidipaks
One Step Calibration kit.
Rainfall calibration
The Rain Collector is calibrated at the factory so the bucket tips (and records rainfall) for each 0.01" (or
0.3 mm) of rain. To calibrate rainfall, we recommend a tube type rain gauge. Use a rain gauge with an
aperture of at least 4 inches. Any smaller and the readings obtained may not be accurate. Place the tube
type rain gauge directly next to the rain collector. Compare the totals on three storms. Based on this,