How to make a Simple Water Level Indicator

Hello friends, Welcome to this electronics tutorial. This tutorial covers the whole explanation and construction of  a useful weekend project that is Simple Water level Indicator. It gives  a visual indication of water level in the water tank using leds. Its circuit is very simple to make and very easy to understand. The total price for making  this project is about Rs.50/- only. So, let's begin to make this project.

Step 1 - Things Needed.

[ Circuit Parts ]

> BC547 NPN Transistor - 5 pieces. ( The number of transistors depend on the number of led you want to use for Indication. 1 Led = 1 Transistor ) | you can use any NPN Transistor.|

> Leds ( Red - 1 piece, yellow - 2 pieces, green - 2 pieces ), { you can choose any color led. }, [ Number of led depends on you. ]

> 100 ohm resistor - 10 pieces. ( The number of resistor depends on the number of transistor you use. 1 Transistor = 2 Resistors )

> Small Switch - 1 piece.

> Project Circuit Board (PCB) - 1 piece.

> 9V Battery cap - 1 piece.

> 9V Battery - 1 piece.

> Some Wires.

[ Miscellaneous Parts ]

> Double Sided Tape.

> Plastic Box. ( Used for Casing the Project )

Step 2 - Tools Needed.

> Soldering Iron.

> Soldering Wire.

> Soldering Flux.

> Wire Cutter.

Step 3 - Studying the Circuit Diagram.

Circuit Diagram

So friends, above is the Circuit Diagram of this project. I request you to please understand the Circuit diagram, So that you had not to face any problem while making this project. If you have any problem/question regarding the Working of the Circuit. then, Scroll down and read the explanation of working of the Circuit.

Circuit Diagram

Working of the Circuit :)

The Whole Circuit is a combination of 5 Small Circuits. So, if we know about the working of a Single Circuit, then we can easily understand the whole working process of the Circuit. 

[Small Circuit]

The main Component of the circuit is a BC547 NPN Transistor. It acts as a Switch for turning on and off the led. It works as when the base of the NPN Transistor receives the (+) voltage from battery via water (Water is a good Conductor of Electricity), the transistor gets Switched on ( Click here to see the datasheet of BC547 NPN Transistor ). So, When the transistor gets switched on, the Collector of transistor gets Connected to emitter within the transistor and in the Circuit, the collector is connected to negative of led via 100 ohm resistor ( 100 ohm resistor provides the desired voltage required for the led to work properly) and emitter is connected to negative of battery which as a result connects the negative of led to negative of battery. Now, for the led to glow, it requires (+) from battery and in the Circuit, the positive of led is already connected to positive of battery and the led is now getting desired power to glow. 

When the sensor wires leaves water, the connection between base and (+) of battery breaks and the led stops glowing. and like this all the Circuit Works and acts as a Single Circuit.

So, friends this is the explanation of the Working of the Circuit...

Simple Water Level Indicator

For better Explanation, Please Watch the Video and please send your feedback/suggestions for any enhancement in the video.

I hope you like this Electronics Tutorial. If you have any Problem, then ask me in Comment Box.