electrical engineering

1. 11
GOVERNMENT
POLYTECHNIC DAHOD
 DEPARTMENT:-ELECTRICAL
ENGINEERING

2. 2
Automatic irrigation system
Presented by:
Chauhan Natvar s.

3. 33
CONTENTS
 Introduction
 Features of 16F877
 List of component
 Block Diagram
 Pin diagram
 Schematic Diagram
 Power Supply Circuit
 Block Diagram Of Regulated Power Supply System
 Component used in project
 Advantages

4. 4
INTRODUCTION
 AIM OF THE PROJECT IS TO MEASURE SOIL MOISTURE AND
START THE PUM AUTOMATICALLY WHEN SOIL IS DRY
 MEASURED VALUES IS DISPLAYED ON LCD.
 LIMIT CAN BE SET BY SWITCHES.
4

5. 5
PIC16F877 FEATURES
5
 Fully static design
 Single 5V In-Circuit Serial Programming capability
 In-Circuit Debugging via two pins
 Processor read/write access to program memory
 Wide operating voltage range: 2.0V to 5.5V
 High Sink/Source Current: 25 ma
 Power saving SLEEP mode
 Selectable oscillator options
 Low power, high speed CMOS FLASH/EEPROM
Technology
 Commercial, Industrial and Extended temperature
Ranges

6. 6
List of component
 Microcontroller pic16f877 40 pin dip
 16x2 LCD
 12-0-12VAC TRANSFORMER/500MA
 Diodes 4007 (Quantity-2)
 Cap 470uf/100uf
 5v regulator 7805 with heat sink
 ceramic buzzer
 Resistor (Quantity-2)
 Capacitor
 LEDS(Quantity-3)
 Variable resistor (Quantity-2)
 LM358 (Operational amplifier)

7. 7
BLOCK DIAGRAM
12/18/2019 7

8. 8
DISCRIPTION OF BLOCK
DIAGRAM
• System is based on PIC16F877 controller.
• Power supply is given 5 v. which is derived from ac 230v.
• 16x2 LCD is there to display the measured parameters on the LC
D screen also it displays set parameters on LCD.
• we have used copper wire for sensing the moisture of soil
• this dc voltage is measured and moisture value is displayed on L
CD.
• we can set the parameter values using four switches
set limit and measured value display on LCD.
• if the measured values is more than limit pump is switched
off
• if less then limit pump is switched on.
• we can send sms on the preprogrammed number for status of
the project.

9. 9
Pin diagram

10. 10
POWER SUPPLY CIRCUIT
10

11. 11
 Ac voltage is coming from step down transformer.
 Rectified by two DIODS filtered by 470UF cap.
 3pin regulator gives 5vdc.
 All electronics parts are working on regulated 5v dc.
 A12v transformer gives ac output 7805 to deliver 5v dc regulated output
microcontroller LCD detectors are working on ac output from current transformer
and potential transformer goes to detector input.
 Detector circuit gives dc output voltage or operational to the microcontroller and
displayed on LCD.
 We measure temperature through lm35 and display on LCD.
 We measure humidity by humidity module and display on LCD.
Using four switches we can set the parameters limits and if any parameter exceeds
the limit alarm and tripping action is taken.

12. 1212
REGULATED POWER
SUPPLY SYSTEM

13. 13
 Transformer-steps down ac voltage + provides electrical is
olation.
 Rectifier-converts AC to DC.
 Smoothing-smooth the AC to DC, ripples are there.
 Regulator-delivers fixed dc output without ripple.
 Types of different waveforms
 Transformer only
 Transformer+ Rectifier
 Transformer+ Rectifier+ Smoothing
 Transformer+ Rectifier+ Smoothing +Regulator

14. 14
LM7805 S (voltage regulator)
 Voltage regulator ICs are available with fixed (typically 5, 12
and 15V) or variable output voltages.
 They are also rated by the maximum current they can pass. Neg
ative voltage regulators are available, mainly for use in dual su
pplies.
 Most regulators include some automatic protection from excess
ive current ('overload protection') and overheating ('thermal pro
tection').
 Many of the fixed voltage regulator ICs have 3 leads and look l
ike power transistors, such as the 7805 +5V 1A regulator show
n on the right.
 They include a hole for attaching a heat sink if necessary.

15. 15
Fig. of LM7805 S (voltage regulator)

16. 16
Relay
 A relay is an electrically operated switch.
 current flowing through the coil of the relay creates a magnetic
field, which attracts a lever and changes the switch contacts.
 The coil current can be on or off so relay have two switches po
sitions and they are double throw (changeover) switches.
 Relays allow one circuit to switch a second circuit, which can b
e completely separate from the first.
 For example a low voltage battery circuit can use a relay to swi
tch a 230VAC mains circuit. there is no electrical connection in
side the relay between the two circuits, the link magnetic and m
echanical.
 The coil of relay passes a relatively large current, typically 30m
A for a 12V relay, but it can be as much as 100mA for relays d
esigned to operate from lower voltage.

17. 17
Microcontroller core feature
 High performance RISC CPU
 Only 35 single word instructions to learn
 All single cycle instructions except for program branches which are two cycle
 Operating speed: DC - 20 MHz clock input
 DC - 200 ns instruction cycle
 Up to 8K x 14 words of FLASH Program Memory,
 Up to 368 x 8 bytes of Data Memory (RAM)
 Up to 256 x 8 bytes of EEPROM Data Memory
 Pin out compatible to the PIC16C73B/74B/76/77
 Interrupt capability (up to 14 sources)
 Eight level deep hardware stack
 Direct, indirect and relative addressing modes
 Power-on Reset (POR)
 Power-up Timer (PWRT) and
 Oscillator Start-up Timer (OST)

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Advantages
 Simple design and install
 This is very useful to all climatic conditions any it is economic friendly
 This makes increase in productivity and reduce water consumption.
 Here we are micro controllers so there is error free.
 This is safest and no manpower is required. Permit other yard and garden w
ork to continue when irrigation is taking place, as only the immediate pl
ant areas are wet.
 Reduce soil erosion and nutrient leaching.
 Reduce the chance of plant disease by keeping foliage dry.
 May be concealed to maintain the beauty of the landscape, and to reduce va
ndalism and liability when installed in public areas.
 Require smaller water sources, for example, less than half of the water need
ed for a sprinkler system.

19. 1919
Thank You!