SR50A Sonic Ranging Sensor
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2 Introduction
The SR50A Sonic Ranging Sensor measures the distance from
the sensor to a target. The most common applications are
measuring snow depths and water levels. The sensor is based
on a 50 kHz (Ultrasonic) electrostatic transducer. The SR50A
determines the distance to a target by sending out ultrasonic
pulses and listening for the returning echoes that are reflected
from the target. The time from transmissions to return of an
echo is the basis for obtaining the distance measurement.
Since the speed of sound in air varies with temperature, an
independent temperature measurement is required to
compensate the distance reading for the SR50A. A simple
calculation is applied to initial readings for this purpose.
The SR50AT version of sensor comes with a temperature
probe that will allow the SR50AT to output temperature
compensated values.
The SR50A is capable of picking up small targets or targets
that are highly absorptive to sound, such as low density snow.
The SR50A makes use of a unique echo processing algorithm
to help ensure measurement reliability. If desired, the SR50A
can also output a data value indicative of measurement quality.
The SR50A was designed to meet the stringent requirements of
snow depth measurement which makes it well suited for a
variety of other applications. The rugged aluminium housing is
built to withstand harsh environments and offers several
mounting options.
