This is very useful device and must be installed in almost every house. Although these type of devices are already available in the market. But they may be costly and may not be durable and accurate for 7 level indications. So here I am going to tell you about how to make it at home like a professional one. See this video for its live functionality.

First of all you need to make its circuit. Although its circuit is easy as I made it using the IC ULN2003 which is an eighteen pin IC. 7 pins of this IC are dedicated for 7 inputs that are connected with the sensors installed in the water tank. Other 7 pins provide the outputs for 7 levels. To describe the circuit diagram here in detail may be long and tedious. I have made its very easy and comprehensive circuit. I presented it in a very professional way through the Power Point and then converted it into a very convenient video format. You may watch it by simply clicking here.

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STEP-2: You should make an indication display panel as you like or as per your convenience. Fit the circuit into this panel. you may feed it with 5 volt power supply. You may keep the power supply built-in or you may use an external mobile charger also.

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STEP-3: For sensing the water levels you need 7 sensors to sense the different levels of your water tank. I made it with good quality nut bolts in a piece of cpvc pipe and connected all the sensors to the circuit using copper wires. For a common probe I just used aluminum stick. See the detail in this video. As my water tank is made up of concrete material. Therefor I have fixed it firmly in the wall permanently. For complete view see my video carefully.

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You must install your indicator unit where it is most convenient for viewing and also should be closed to the water tank. This water level circuit works very accurately at each level. So make it and install it in the water tank of your house.