Today I am going to talk about a very useful project that I had taken up. It is called the Water Level Indicator. Nowadays everybody has overhead tank at their homes. But everyone who has a water tank above knows the kind of problems that they face. Firstly there is no system to track the water in the tank. Then there come a secondary problem that is when their water pump is started they have no idea when it gets filled up and sometimes there are situation where the pump keeps on pumping water to the tank and the water starts spilling out from the tank. There is wastage of energy as well as wastage of water.

Later History
This project that i had taken up is the result of  long hours of research of work at the Internet as well as long hours of thinking. I had made various versions of the projects earlier but at last i came up with this final product. I bet this has been tested and i can now firmly say that the model would work flawlessly without any complains for years. I am saying this as i have installed this models to various houses in my neighborhood and all are working fine without any maintenance. And indeed this model is admired by all who uses it.

The Situation 
The house where I live in has an overhead tank which is about 30 feet from the ground level. I was getting bored going up the rooftop to check whether the tank has filled or the water level was below to start the pump. I had to do this again and again. Then I sought for a solution. I always used to think of the possibilities of how can this problem be tackled in an electronic way. After years of research and by trial and error,  I found one and wanted to put whatever I have done out here so that it may be helpful to someone who has a overhead water tank at their homes.


Step 1: The Working Principle

Basically the unit is made up of various sensors acting as a switch. Let me explain in a simple way. What happens is when you turn on you water pump, the water starts to get pumped from your underground reservoir  or from your underground water supply from the pipes to your water tank. In the tank there is a set of sensors ( to be precise there are 7 sensors), in the water tank. Just think them as a switch, as the work of the sensor will be to connect a circuit. I will explain in details in my instructables. So the water starts to get filled in the tank and when the water level in the tank starts to rise up, what happens is that the sensors that is installed in the tank starts to get activated one by one indicating the water level in the tank. And finally when it reaches to its top most sensor, there will be a visual display as well as a sound from the unit indicating that the water has filled in the tank and one can be alerted that the tank has been filled up and the water pump has to be switched off saving the electricity bill as well as over flow of water from the tank.

There are Four parts in this project:-

(i) The Sensor Part

It is generally a fixed support inside the tank having some nuts and bolt with wires coming out.
(ii) The Circuit Part
It comprises the brain of the module, where in all the various inputs from the sensors are fed. It is the unit from where you will get all the information of how much of water is in the tank.
(iii) The Power Supply 
It is the part where in you will be converting the A/C voltage to a regulated voltage of 5V to the Circuit.
(IV) The Buzzer Part
It is responsible for bringing up the sound when the water level fills up in the tank. It will also be having a speaker or a buzzer to alert.
<p>the power supply is 9v or 5v ?</p>
<p>You can use either 5V or 9V...:)</p>
What if i use a12v adapter
<p>can any one please tall me the exact materials i am going to use and how many of them because im gonna try to do this project </p><p>thanks :)</p>
<p>what if we don't use Power Regulater 7805????</p>
<p>thanks raikut for this project.. ive made every exactly you have written but the sensors in overhead tank gets corroded in just two weeks . after that the buzzer sound gets low and some LED's start flickering. pls telll m some solution on this.</p>
Hm I also have same issue , what I do is cleanup wires every month :(
<p>Hi,</p><p>Have you tried anti-corrosive(AC) materials like AC paint or AC powder which are available in market. I am also planning to make one for my home.</p>
<p>This can cured by using a float that is sealed and designed to be in water. It acts as a switch. I have two 2500 gallon water tanks with 5 floats attached to it. No problems and works flawlessly. Electronics submerged in water will only last for so long due to electrolysis, the same phenomenon on outboard motors which is why they have zinc plate that is softer than the metal for the motor. So it eats away slowly at that instead. Email if you want help.</p>
<p>Hello Jason,<br>Can you provide the details on how to construct the floats?<br><br>Will be much obliged :)</p>
<p>can you pls send pic of tht switch?? or its web link.</p>
<p>Hi! Can I ask what is the value of the capacitor and the wattage? Do we use 2 or just 1 capacitor?</p>
9v adapter
can use 5v adapter
<p>can i use 560k ohm resistor in place of 470k ohm resistor for biasing the transistor and also i am applying 12v dc current to the circuit?????</p>
<p>can i use 560k ohm resistor in place of 470k because it is not available in my place and also i am applying 12v dc to this circuit..</p>
<p>i am so much impressed by this project i just love it and im going to make it for my class project.</p>
<p>i have made it but my family is afraid of installing it they are afraid if it will very dangerous to work with taps when this circuit is in on condition</p>
Don't worry... This circuit uses 5V DC which will not give you an electric shock. It is perfectly safe.
What is the longevity of the probe ? Sooner or later it is going to rust and it will be virtually cut off from the water... So which material should we use ?
<p>Hi friends,</p><p>One of my friend has build this Water level indicator to keep at his home. But the water seems to be non-conductive. Its acts as an insulator. Even We did check with multi-meter on the continuity mode. but still no conduction is happening. I am not able to resolve his problem. Could anyone help me on this... </p>
Most probably there's a deposition of oxide layer over the probe... which is decreasing the conductivity drastically... Try rubbing the probe with a sand paper and see.
Nice One
Can i just use dc supply rather than ac supply?
<p>any one plz tell me the value of capacitor that we are using in bridge rectifire...</p>
<p>Use 100 micro farad capacitor</p>
<p>Can anyone help me with the terminals of BC547. I am a bit confused :/.</p>
<p>ls refer the snap shot below</p>
Can i please know how much did this cost approximately ?
<p>It will cost you around 150rs</p>
<p>instead of connecting to main power supply can i use 9v</p><p>is it work for large size tank</p>
<p>You can use either 5V or 9V...:)</p>
Hello sir pls give me your mobile no I have some doubts sir
Hi i made this ckt it work s perfect but when tank is full buZzer is not ring loudly.<br><br>When i short comon wire n last led wire it rings loudly.<br><br>Any one can help me to solve my problem.<br><br>Thanks in advance.
<p>i also want to design pcbs so i will be very thankful if anyone can tellme all the requirements for designing and printing of pcbs at home</p>
<p>i want to know any good microcontroller programmer hardware and software as i want to learn to program and burn almost every kind of microcontroller so can anyone please tell me name of a goof microcontroller programmer device that supports almost every microcontroller...</p>
<p>can i use 400k ohm and 47 ohm resistors</p>
<p>Hi can any one tell me how to get rid of electrolysis problem which break wires in water tank </p>
hei i just connected the relay directly to the last output, i have given the relay a 12 v supply directly, and the neutral is via the master ckt, relay seems to work, can i connect it to motor???
Hei thanks for this simple circuit, i just made it, I just want to know if i can drive a relay to stop the motor. My logic is , 'take the output of the last level give it to a driver IC like L293D, get a 12v output frm IC andr drive the relay, its a 1/2 h.p 240v motor, I wanto connect it directly between phase lines, like a switch' is there any flaw??? help me out
There is mistake in showing collector and emitter of the transistors. Collector should go to positive hence LEDs cathode should be connected to collector of BC547 and emitter should go to common negative line.
This issue has been discussed earlier, please go through the comment section and watch the given video<br> <br> <div class="media_embed"> <iframe frameborder="0" height="315" src="http://www.youtube.com/embed/mb66rti1Qx8" width="420"></iframe></div>
Transister will work though biased collector emitter inversely . Collector is lightly doped in order to have high voltage withstand capability. However, one major advantage of operating the npn transistor with its emitter and collector roles reversed is that the saturation voltage drop across collector and emitter is lower than that obtained in the normal mode, inspite of having lower current gain. This is why such devices were used as analog switches in low voltage control electronics in discrete applications. So no problem we can go head with this collector emitter inverse connection as this circute is operated by low voltage. No much power gain . So there wont be much heat to dissipate . I think for buzzer it is better to connect load in the collector line . <br>information courtesy :-Sujit K. Biswas &middot; Jadavpur University.
<p>Use aluminum foil (2 pcs) glued to a plastic backing as an electrode plate. will weather far longer than just wires.</p>
<p>hey guys could someone explaine the circuit analysis</p>
<p>I have doubt whether this will have electric leakage in water tank leading to shockage. Kindly clear my doubt</p>
<p>Nice one. However, one problem with such circuits is the corrosion of electrodes due to the high current. I've been using this <a href="http://www.electronic-circuits-diagrams.com/water-level-indicator-circuit-with-alarm/" rel="nofollow">water level indicator</a> circuit for several years and hardly needs cleaning. Maybe its the low current needed to trigger the CMOS IC switch.</p>
Which diode will i use as the full wave. Rectifier
Which diode will i use as the full wave. Rectifier
<p>can some one let me know the parts used</p>

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