A water-level controller for greenhouse sump tank

A water-level controller has been developed on hysteresis effect. In a greenhouse the sump tank is often located underground. Water levels are monitored with a high and low alarm. The sump pump is turned off and on according to the water levels. In a general way the sump pump is turned off and on by floats in the tank. Floats may be corroded and wear out prematurely because of the bad condition in the tank. In our project a controller for bad conditions is designed. A low-voltage electronic circuit that senses upper and lower water levels is used for alarms and sump pump activation. Since the electronic sensor has no moving mechanical parts, it eliminates problems with corrosion and wear and tear. It is cheaper and more durable than float system and can be used treatment of greenhouse recirculation water and the irrigation system in a greenhouse.