This document describes an automatic water level controller system using a microcontroller. The system controls the on/off state of a water pump based on the water level in an overhead tank. When the water level drops below 10%, the pump turns on, and when it exceeds 90%, the pump turns off. The water level is also displayed using LEDs. The system prevents dry running of the pump by only turning it on when sufficient water is available.

1. AUTOMATIC WATER LEVEL
CONTROLLER USING
MICROCOTROLLER
Prepared By : Jadeja Mohitraj (090010111004)
Muni Dimitra (090010111009)
Group No : ADITEC04
Guided By : Mrs. Heena Kher

2. Introduction
 Definition: Automatic water level controller using microcontroller.
 AIM:
• To reduce wastage of water by switching automation.
• To Increase pump set life.
• To save electricity.
 OVERVIEW:
• This project consists of implementation of house based automatic water level
controller using microcontroller AT89c51.
• In this system we can observe status of water.
• Here system is made such that it won’t work on Dry run condition. It will only
switch on the motor after there is sufficient water in ground tank.

3. Working
 It is a microcontroller-based water-level controller. It controls ‘on’ and ‘off’
conditions of the motor depending upon the level of water in the ground
tank.
 Working of the pump is controlled by the water level of the source tank,
if the ground tank is empty then pump gets automatically on and when it
is 90% filled then pump gets automatically off.
 When there is no water in the source tank, pump will remain switched off.
 Working of the pump totally depends upon both, the source as well as main
tank.
 The level of water in the tank is displayed on LEDs.

4. Block diagram

5. Flow Chart

6. Description of flowchart:
1. First status of ground tank is checked, if ground tank doesn’t have water the
buzzer will turn on otherwise process is continued.
2. Further motor will turn on if water is below 10% level of total overhead tank.
3. If water exceeds the 90% level of overhead tank, motor will automatically turn off.
4. Simultaneously status of water is shown on LEDs indicating water levels.

7. Circuit Diagram

8. DESCRIPTION OF CIRCUIT:
• As show in circuit P10 to P13 pins are input pins which are used to input data in
controller based on status of water in overhead tank.
• Metal strips sensors are at 10% , 40%, 70%,90% levels in overhead tank.
• According to water level at input side corresponding LEDs will glow.
• Simultaneously water level is controlled as water levels goes below 10% level
motor switches on and when level goes above 90% level it turns on.

9. OPERATION:
• There are two conditions for water in ground tank.
1) Water is insufficient to switch ON the motor.
2) There is sufficient amount of water in ground tank to switch ON the motor.
1) Condition : Insufficient water
• In ground tank water is insufficient to switch ON the motor so motor will be off.
• In this condition dry run of motor is avoided so we can save electricity as well
motor pump set life is increased.
2) Condition: Sufficient water
• If water in the source tank is above some level then motor will turn ON and water
is pumped to the overhead tank.
• Overhead tank is filled to maximum 90% level of the tank.Then automatically
motor is off.
• Again if the overhead tank water level decreases then motor will get automatically
turned ON.We also can see status of water in Overhead tank on by LEDs.

10. Components
 Optocoupler:
• The main purpose of an Opto-isolator is “to prevent high voltages or rapidly
changing voltages on one side of the circuit from damaging components or
distorting transmissions on the other side”.
• Optocoupler IC is with 4 inputs and 4 outputs and total 16 pins .
• Here Anode is connected to +5V voltage supply. Cathode is connected to ground.
• Collector is connected to +5V supply directly. Emitter is used as output which is
fed to pin 1 to 4 of port1 as input.

11. Components
 LEDs:
• In this system four LEDs are used to indicate status of the water in Overhead tank.
• LEDs are connected in such a way that their cathode terminal is connected to
ground. So when output is high on output pin LED glows else it doesn’t glow.
• Anode terminal is connected to Port 2 pins 20 to 23, each with one LED.
 Transistors:
• In this we have used two NPN transistors.
• One NPN transistor will be used to turn the motor on and off.
• Other NPN transistor is used to turn ON-OFF the buzzer.
• In each case NPN transistor works as a switch.

12. Components
 Crystal oscillator:
• Crystal Oscillator is used to provide continuous clock signal to pin 18-19 to get precise
frequency of operation.
• Here crystal oscillator is made up of piezoelectric material which by giving voltage,
vibrates at specific frequency.
• We have used 12MHz frequency crystal.

13. Water Pump :
• For pumping the water we have used a Fountain pump for serving the purpose.
• Voltage 165-220V / 50Hz and Power: 19W.
• It is only used in sufficient water condition.Dry run must be avoided.

14. Components
 Resistors:
• Color coded resistors are used.
• Resistor normally here used is of 5V voltage rating.
• Various values of resistors like 1K, 4.7K are used.
 Capacitors:
• In this circuit capacitor is used in crystal oscillator.
• We have used two capacitors of 33pf.

15. Components
 Buzzer:
• Here we have used a buzzer of 200 Hz frequency.
• One terminal of buzzer is connected to ground.
• Other is connected to output of pin no 28 of controller IC.
 Microcontroller(AT89C51):
• It is 40 pin IC driven by single 5V power supply.
• Here we have used only two I/O ports.

16. Microcontroller

17. Final circuit

18. Final Circuit

19. Pin Description

20. Results
• Using keil uVision3 software we got the o/p as follows:
1) Initially at running the code , Initially if ground tank has no water P2.7 is’1’(buzzer ON).
2) Making pinP1.4, ‘1’(sufficient water), we got P2.6 ‘1’(motor ON).

21. Results
3)Now if pin P1.0 is ‘1’ then pin P2.0 is ‘1’.(motor is also ON and P1.4 at ‘1’)
4)If pins P1.0 and P1.1 are at ‘1’ then pins P2.0,P2.1 are at ‘1’(motor is also ON and P1.4 at
‘1’)

22. Results
5)If pins P1.0,P1.1,P1.2 are at’1’ then pins P2.0,P2.1,P2.2 are at ‘1’(motor is also ON and
P1.4 at ‘1’)
6)If pins P1.0,P1.1,P1.2,P1.3 are at ‘1’ then pins P2.0,P2.1,P2.2,P2.3 are at ’1’and P2.6 is
at’0’(motor is OFF and buzzer also OFF)

23.  Advantages:
• Less power consumption.
• C program can be easily modified if required.
• Further modification or addition of extra circuitries and components is possible.
• Low cost.( approximately 500Rs., motor expense not included).
• Higher processing speed.
 Limitations:
• Number of LEDs for indicating water level is limited so maximum number of
water levels shown here is also limited.
• Use of metal wire as sensor may not work for a large water tank .
• To overcome this limitation another amplifying circuitry might be required.

24.  CONCLUSION:
 If ground tank has no water, sensor senses ‘0’ level and that is fed to controller
pin P1.4 so further process is avoided including dry run. And buzzer is ON i.e.
pin P2.7 has o/p ‘1’ on the pin.
 And continuous monitoring is going on. And If suppose ground tank has water,
motor is switched ON for water pumping. Simultaneously water level in overhead
tank is displayed by means of glowing LEDs.
 We are having wire sensors at 10%, 40%,75% and 90% levels. These sensor
outputs are fed to Optocoupler and then to microcontroller as input. According to
signals at input port microcontroller is giving signal at output port .
 This project serves purpose of water saving as well as electricity saving. It has
benefit in terms of ease of expansion and modification(as only 2-ports of
microcontroller are used out of 4).

25.  Technology used :
• In this project we have used microcontroller(AT89c51).We have used keil
uVision3 software for assembly coding for this project.We have also used
multisim10 for creating circuit.
• We used SuperPro software for writing the assembly code (hex file) on the
AT89c51 controller IC.We also used 8051board by MikroElectronika for checking
validity of the assembly code.
 Future Scope:
• In future this project can be expanded in terms of accuracy and number of water
levels taken into account by using ADC.
• Also using VB(Visual Basic) real water level can be shown on the computer and
by the software water level can be monitored.

26. THANK YOU