DESIGN AND CONSTRUCTION OF AN AUTOMATIC WATER LEVEL CONTROLLER FOR OVERHEAD TANK

ABSTRACT The increasing reliance on overhead water storage tanks in households and institutions has made efficient water level management a critical necessity. Manual operation of water pumps often leads to tank overflow, water wastage, pump dry running, and unnecessary energy consumption. This project focuses on the design and construction of an automatic water level controller for an overhead tank using simple, low cost electronic components. The system employs conductive water level probes to detect low and high water levels, BC337 transistors for signal amplification, a 555 timer IC configured in bistable mode for control logic, and a relay for switching the water pump. When the water level falls below the preset low level, the controller automatically switches ON the pump, and when the tank reaches the high level, the pump is switched OFF without human intervention. The entire circuit was first tested on a breadboard and later assembled on a Vero board and enclosed in a protective casing. Experimental results show that the system operates reliably, responds promptly to water level changes, and effectively prevents tank overflow and pump dry running. The simplicity, affordability, and ease of maintenance of the design make it suitable for domestic and small institutional applications, particularly in resource limited environments. Keywords:Automatic water level controller, 555 timer, Relay switching, Overhead tank, Pump control