Design And Construction Of An Automatic Liquid Level Indicator With Alarm

1.0 INTRODUCTION
1.1 Background of the study
The liquid level sensor is a device that measures the liquid level in a fixed container that is too high or too low. The level sensor is a device designed to monitor and measure liquid (and sometimes solid) levels. When the liquid level is detected, the sensor converts the sensed data into an electrical signal. Level sensors are mainly used for monitoring reservoirs, oil tanks or rivers (Henry, 2018).
According to the method of measuring the liquid level, it can be divided into two types: contact type and non-contact type. The input type water level transmitter we call is a contact measurement, which converts the height of the liquid level into an electrical signal for output. It is currently a widely used water level transmitter.
This device consists of 4 LED’s used to indicate ¼, ½, ¾, full levels. Basically the unit is made up of various sensors acting as a switch. This device came to mitigate problems such as poor water allocation, inefficient use, and lack of adequate and integrated water management. Automatic liquid level indicator system is designed to monitor liquid level in an overhead tank. This device helps the user to be aware of the water level in the tank through indicators. It is very useful because the user need not worry about the liquid such as water content during the peak hours of the day. It not only helps in the daily chores but also prevents water wastage. It reduces human labour, saves time and also keeps the user updated regarding the water content (Henry, 2018).

1.2 Statement of the problem
Nowadays, all the householders/owners are storing the water in overhead tanks by using the pumps. When the water is stored in the tank, no one can identify the level of water and also, no one can know when the water tank will fill. Hence there is an overflow of water in the tank, thus there is wastage of energy and water. To resolve this type of problems a water level indicator is built to indicate the level of liquid such as water in the overhead tanks.

1.3 Aim and objectives of the study
This work is aimed at building a liquid level indicator that will use four sensors to detect and indicate the four level of liquid in a container.
The objectives of the work are:
i. To build the system prototype at low cost
ii. To learn the working of a liquid indicator
iii. To automatically detect liquid level (1/4, ½, ¾ and full) with high precision.
iv. To control the supply of liquid thereby saving liquid.

1.4 Significance of the study
This study will bring solution to an overflowing of liquid from a container thereby preventing water wastage and saves electric energy. With this study, one can identify the level of liquid in a container. This study will also serve as a means of enlightening students on how to build simple electronics circuits.

1.5 Scope of the study
The scope of this work covers building a liquid level indicator using CD4066 CMOS IC as the heart of the circuit. The circuit consisting of 4 LED’s used to indicate ¼, ½, ¾ and full levels. When the liquid is full, the base of the transistor BC148 is pulled high by the liquid and this saturates the transistor, turning the buzzer ON thereby informing the user that the container is filled.