The OTT RLS uses a energy-efficient impulse-radar technology for measuring water levels. During each measurement the sensor sends radar pulses down to the water surface, the pulse are then reflected from the surface of the water and detected by the receiving antenna of the OTT RLS.

The time from transmission until reception of the reflected pulse (time delay) is longer the further the OTT RLS is from the water surface and thus the lower the water level. This correlation is used by the OTT RLS to determine the time delay and caculate the distance to the water surface.

Water Level Sensor TSP - Product sheet