# \$1 AUTOMATIC WATER LEVEL CONTROLLER

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## Introduction: \$1 AUTOMATIC WATER LEVEL CONTROLLER

Hello friends

Today I am back with another project called \$1 AUTOMATIC WATER LEVEL CONTROLLER.

It’s an automatic switching circuit that used to control an AC water pump. Operation of this circuit is simple.wen the water level goes below the limit the lower level sensor will detect it and activate the water pump.wen the water level reaches the upper limit the upper limit sensor detect it and switch of the water pump.

## Step 1: My Goal

“To make a cheap but efficient water level controller under \$1 budget to control AC water pump”

## Step 2: The Circuit

This is the driving circuit of the \$1 AUTOMATIC WATER LEVEL CONTROLLER.

To make this circuit you will need

1. BC 547 Transistor X 3 = 9 INR
2. 220 K Ohm & 5.4 K Ohm resistors = 1
3. 1N4007 Diode = 1
4. 12V relay = 12
5. One, 3-pin PCD connector & two, 2-Pin PCB connector = 25
6. Wires = 5
7. PCB = 12

Total = 66 INR

Total cost of this circuit is equals to 66Rs or 66INR (66.6 INR = 1 USD).that means this circuit is under the \$1 budget

12v relay is the main component of this circuit, so please use a relay with 7Amp or more. I am using a 12v relay.it can handle 7 Amp AC @240v.

## Step 3: The Sensor

To make sensor you don’t need anything special. Take three wires and name them like LOW, HIGH AND MAIN. Place “MAIN” on the bottom of the tank. Then place “LOW” above the outlet. Finally place “HIGH” on the top of the water tank

[ ~~~~~~~~~~~~] -------------------------------------- “HIGH”

[~~~WATER~~~ ]

[ ~~ TANK ~~~~~]

[~~~~~~~~~~~~ ]

[~~~~~~~~~~~~ ]--------------------------------------- “LOW”

[______________]--------------------------------------- “MAIN”

This is the placing order of the sensors

## Step 4: ​Connect Them All

Connect all wires to the main circuit board with help of circuit diagram. Double check all connections because playing with high voltage is DANGER

## Step 5: The Moment of Truth

This video show how \$1 AUTOMATIC WATER LEVEL CONTROLLER work

Runner Up in the
Sensors Contest 2016

Participated in the
Home Hacks Challenge

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• ### Make it Glow Contest

What is the working principle of this circuit? How does it work? Could you also provide a detailed working explanation for the people new to electronics?
- Thank you!

What do i need to make it 5v instead of 12v

You need to include a circuit that shuts the pump off if the flow stops. Or you need to make sure everyone knows the way you show the current circuit is not intended for deep well pumps. Series a well can be pumped dry, and if this happens and it keeps on trying to pump it can burn up an expensive pump. I was wondering if a signal from a flow meter might be used to prevent the pump from running without flow. Something to ponder.

How I can use the same system to empty the tank... I am new to this as electronic... Please let me know how... It's to pump out the water from my air conditioner external tank... On went is full and go off at the minimum level to not Burns the water pump.

Its a nice project and I am just starting with mine.

In PDF version of the project , after downloading I found a serious mistake in the circuit diagram.The collector of the first transistor BC547(to which resistor 220K is connected in the base) is not connected to the +ve rail.

Hey can i get a pcb layout for my project? Thank you!

Wat was the logic needed to support underground sump tank, so that motor runs only when the water is sufficient.

Use a DPST relay and use the NC contacts.

I need to use a relay that draws more than 100ma. I assume that the BC547 transistor was chosen because of it's gain of 800, but it will not drive more than 100ma. I would normally substitute a 2N2222 in this instance because it will supply up to 800ma, but it only has a gain of 100. In this circuit, can 2N2222s be substituted for all 3 transistors and it still function properly (I assume that the bias resistors will have to have lower values)? If not, can a 2N2222 be substituted for just the relay driver? Thank you in advance.

I tried, but when only main and low that be under water the relay ia flickering. Why?

From where we can order some items \$1 AUTOMATIC WATER LEVEL CONTROLLER?

Nice and simple! Reminded my hobbyist days years back!

Any mod to include logic/circuit to support an underground sump so that the motor runs only when there is sufficient water in the sump?

definitely yes,but you need to tweak the circuit little bit

Would like to thank you for this useful simple project.

I made it on a breadboard and running for last 3/4 days without any problems. I have added 2 LED to indicate circuit is online + AC line ON/OFF with a 12v DC 1000mA power supply even you suggest not to add LED for circuit. what if I use a 1500mA power supply ? as you said LED itself takes 1A !

before I go for PCB layout I would like to see back side connection of your PCB as it looks very neatly assembled. Thanks for your time.