Water Level Indicator With Alarm





Introduction: Water Level Indicator With Alarm

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.

Step 1: Things You Need...

4 - bc548

6 - 220 ohm resistors

3 - colour led

1 - buzzer

1 - 9v battery + battery clip

Step 2: Circuit Diagram

The circuit consisting of 5 sensing probes which is dipped in water to sense the level of water. The probe A is connected as common to other four , which should be at the bottom most part of the water tank, also it act as a reference level. The probes B, C, D and E are set as minimum, minimum+ , middle and maximum level respectively.

Assemble the circuit...... 

Step 3: FINISH.. :)

When water in the tank touches the probe A and B both, a small current flows from A to B through water and to the base of transistor T1 via a 220KΩ resistor. As a result the transistor conducts causing the LED1 to glow. Similarly, when water touches sensor C, LED2 glow and indicates that WATER is at minimum+ and when water touches sensor D , LED 3  glow and indicates that WATER is at. MIDDLE . Finally, when the water touches sensor E ,  BUZZER turns on and indicates the tank is completely filled.

3 People Made This Project!


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This is exactly the circuit I was looking for but battery wouldn't work for me as it's in a machine shop and we have too much going on to keep track of it and I don't feel like making a low voltage circuit, but I do have a 5v 1A wall wart, and all my math says I can do it, albeit my LED's may be dim...thoughts?

Also, very nice instructable, but maybe you could put the specs of some of the things you used (i.e. wattage of resistors, speaker specs etc.)? I know that for this circuit you could easily use a 1/8w resistor but the speaker I just kind of hummed a few bars and faked it and used a 1.5v speaker and put an LED in front of it to step the voltage down a touch.

use a battery adapter in the place of a battery , soo that it reduce the cost and save your time also .

I'm going to use a voltage divider and knock it down some. I lose a little in heat but it's for a Wire EDM water tank that I'm constantly over filling (and that wreaks havoc with the accuracy) so it'll get some cooling. Thanks for the response!

thankyou sir , for your positive feedback .

maybe you can by modify the above circuit accourding to your requirement . :)

Does this work with motor oil?

If it works with motor oil you have much bigger problems than oil level :)

no sir , Engine oil does not conduct electricity
because there are no charge carriers in it.

This can prove useful in my boat. Thank you much for posting

Made something like this only difference I put the alarm on empty with a pnp- instead of a npn-transitor