The Automatic Water Level Recorder (AWLR) is manufactured as per IS speficification & is an instrument that is both float-driven and time-driven.
It consists of mainly Float, pulley, Chart Drum, electronic clock, pen assembly. The Electronic clock ensures precision timing of chart. This instrument records changing levels of water surface in relation with time. In Weirs, canals, water flow data are obtained using AWLR, where height is an index of flow.
The rise and fall of the float with changing water levels turns the pulley & drum proportionally, as the timer controlled marker moves across the chart at constant speed. The resulting graph shows the water level against time.