This document describes an automatic irrigation system that uses a soil moisture sensor and Arduino microcontroller to control a water pump. The system senses the moisture level of the soil and turns the pump on or off to water the plants accordingly. It aims to help farmers efficiently irrigate their fields without wasting water or requiring constant human monitoring. When the soil is dry, the moisture sensor sends a signal to the Arduino, which activates a relay to power the water pump. When the soil becomes wet again, the pump is turned off. The system uses low-cost, reliable components and provides benefits over manual irrigation methods.

1. AUTOMATIC IRRIGATION
SYSTEM ON SENSING SOIL
MOISTURE
Submitted by
BATCH NO:16
P.MURALI-15H65A0211
B.YOGESH-15H65A0202
B.MANISH-13H61A0205
T.AKANSHA-14H61A0203
Under the Guidnce of
Mr.M.LALU(Asst.Professor)
Department of EEE

2. ABSTRACT:
 The project is designed to develop an automatic irrigation system
which switches the pump motor ON/OFF on sensing the moisture
content of the soil.
 The project uses ARDUINO UNO R3 in which ATmega328P
microcontroller.
 which is programmed to receive the input signal from the
moisture sensor.
 This is achieved by using an op-amp as comparator LM385.
 Once the controller receives this signal, it generates an output
that drives a relay for operating the water pump.

3. PRESENT SCENARIO:
 In present days, especially farmers are facing major problems in
watering their agriculture fields, its because they have no proper
idea of when the power is available that they can pump water.
 Even after the power comes, they need to wait until the field is
properly watered, which makes them to stop doing their other
works.
 To avoid this problems by automatic irrigation type projects are
helpful.

4. BLOCK DIAGRAM
POWER SUPPLY
ARDUINO RELAY DRIVER 12V PUMP
LCD
230V AC SUPPLY
MOISTURE SENSOR
12V DC
ANALOG DIGITAL

5. COMPONENTS
• TRANSFORMER (230-12V AC)
• RECTIFICATION
• ARDUINO
• MOISTURE SENSOR
• RELAY CIRCUIT
• WATER PUMP
• LCD

6. • TRANSFORMER:
A step down transformer is used which steps down the
voltage from 230v to 12v ac.
• RECTIFICATION:
By using a bridge rectifier circuit the ac supply is converted
to dc.
• ARDUIUNO:
Arduiuno is used to control the whole process. The output of
the soil moisture sensor is connected to the digital pins of the
arduiuno.

7. • MOISTURE SENSOR:
The moisture sensor senses the moisture content in the soil
and gives an analog output which needs to be interfaced with
the arduiuno.
• RELAY CIRCUIT:
The relay is used to control the small water pump and it is
driven by transistor. The transistor is further connected to the
digital pin of arduiuno.
• WATER PUMP:
A 12v dc water pump is used to artificially supply water. It can
be triggered ON/OFF by sending signals as required.

8. • LCD PANEL:
LCD is used for displaying status and messages. LCD is
used in 4 bit mode and driven by arduiuno library

9. CIRCUIT DIAGRAM:

10. OPERATION:
MOISTURE SENSOR:
The Soil Moisture Sensor is used to
measure the volumetric water content of soil.

11.  The arduino microcontroller which is programmed to receive the
input signal of varying moisture condition of the soil through the
sensing arrangement.
 When the soil condition is less than the reference value, then the
soil is considered as dry.
 The arduino microcontroller then turns ON the motor drive circuit
prompts the motor to pump water to the plants.
 When the soil condition is greater than the reference value, the soil
becomes wet.
 Then controller turns OFF the motor driver circuit .

12. APPLICATIONS:
• Irrigation in field.
• Irrigation in parks,gardens.
• Very efficient for paddy
• Water sprinklers

13. MERITS:
 Easy to design and install.
 Low cost and reliable circuit.
 Complete elimination of manpower.
 System can be switched into manual mode whenever required.
 Mainly it eliminate hazards.

14. CONCLUSION
As water supplies become scarce and polluted, there is a need to
irrigate more efficiently in order to minimize water use and chemical
leaching.
Therefore this project is the best solution for this crisis.
The primary applications for this project are for farmers and
gardeners who do not have enough time to water their crops/plants.
It also covers those farmers who do not waste water during
irrigation.

15. THANK YOU