Multipurpose Head Detection and Monitoring Unit

ABSTRACT A water level (head) detection unit was developed which is versatile in its application. The system used an inexpensive pressure transducer and double-bubbler scheme for sensing water head. The double-bubbler scheme provides a method for continual calibration of the pressure transducer (offset and gain compensated). Head detection accuracy was within ± 1 mm over a wide temperature range. This scheme is monitored and controlled by a hand-held programmable electronic calculator. The calculator and peripheral devices can be used to compute a variety of parameters of interest. This unit has been used along with a measuring flume or weir to record and accumulate flow. It has also been used to monitor infiltration for a flowing furrow infiltrometer. The unit can also be adapted to record water levels from several locations. Since the unit is programmed by simple calculator functions, it is rather simple to convert to new applications.