The SR50A 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 an electronic transducer that determines the distance to a target by sending out ultrasonic pulses and measuring the time it takes for the echoes to return.
The SR50A was designed to meet the stringent requirements of snow depth measurement, so it is well-suited to a variety of other applications. It can pick up small targets or those that are highly absorptive to sound, such as low-density snow. Campbell Scientific Canada builds it to withstand extreme conditions in harsh environments.
Since it uses the SDI-12 protocol, the SR50A supports various commands. The different commands are entered as options in the SDI-12 recorder instructioin. The user has the option to output the distance to target in either meters or feet, or to include measurement quality numbers.
Less than 1 sec measurement time
Low power drain on datalogger
Accurate to 1 cm or 0.4 percent of distance to target (whichever is greater)