Orion Car Audio 420 - Manual (Page 15)

Orion 420 Weather Station 15
________________________________________________________________________
Columbia Weather Systems, Inc.
Rainfall Measurement
Rainfall is measured with an impact sensor, which detects the size and
impact of individual rain drops. The signals resulting from the impacts are
proportional to the volume of the drops. Hence, the signal from each
drop can be converted directly to the accumulated rainfall.
This measurement method eliminates flooding and clogging, as well as
wetting and evaporation losses.
The sensor transmitter uses RAINCAP® sensor 2 technology in
precipitation measurement.
The precipitation sensor is comprised of a steel cover and a piezoelectric
sensor mounted on the bottom surface of the cover.
The precipitation sensor detects the impact of individual raindrops. The
signals from the impact are proportional to the volume of the drops.
Advanced noise filtering technique is used to filter out signals originating
from other sources than raindrops.
The measured parameter is accumulated rainfall. Detection of each
individual drop enables computing of rain amount with high resolution.