Swami Sachchidanand Polytechnic College,

Visnagar

PREPARED BY:-

  • GUIDED BY:-

Dasrat. J. Maheshwari(Lecturerin E.E. dept. SSPC VIsnagar)

  • GROUP - J :
  1. Patel Tirth A. (106500309052)
  2. RavalJayesh A. (106500309037)
  3. Rami Jay R. (106500309061)
  4. SutariyaJitendra A. (106500309054)
  5. SathwaraHardik S. (106500309083)

A Project Report on

Automatic Fan Control And Intensity Control By Using Microcontroller

DEVELOPED BY:-

PATEL TIRTH A.

(106500309052)

UNDER THE GUIDENCE OF

Internal Guide:-

Dasrat. J. Maheshwari

E.E. Dept., SSPC, VIsnagar

SUBMITTED TO:

Swami Sachchidanand Polytechnic College, Visnagar

GUJARAT TECHNOLOGICAL UNIVERSITY,AHMEDABAD

Swami Sachchidanand Polytechnic College, Visnagar

CERTIFICATE

TO WHOM SO EVER IT MAY CONSERN

This is to certify that project work embodied in this report entitled “Automatic Fan Control And Intensity Control By Using Microcontroller” was carried out by Group – J (Electrical Eng. Dept.) at Swami Sachchidanand Polytechnic College Visnagar for partial fulfillment of Diploma Electrical Engineering semester 6th to be awarded Gujarat Technological University. This project work has been carried out under my supervision and is to my satisfaction.

Group Members Enrollment No.

Patel Tirth A. (106500309052)

RavalJayesh A. (106500309037)

Rami Jay R. (106500309061)

SutariyaJitendra A. (106500309054)

SathwaraHardik S. (106500309083)

Date of Submission Guide UDP Head of Department

Automatic Fan Control & Intensity Control by using Microcontroller

ABSTRACT

This project will present the design, construction, development, control and evaluation of an automatic switching electric fan and also control the intensity of light. The microcontroller based automatic fan system and light systems presented in this project are required to fulfill the requirement of technologies “tomorrow will be more advanced than today”. The electric fan automatically switches according to the environment temperature changes and lights are switch on one by one according to the room intensity changes. This electric systems are contains combination of sensor, LDR, controller and relay with integration of embedded controlled programming. Finally, this system performance will be evaluated by comparing performance data to the theoretical.

INDEX

Chapter
No. / Contents / Page
No.
1 / INTRODUCTION / 7 to 9
2 / LITERATURE REVIEW / 10 to 27
3 / CIRCUIT DIAGRAM / 28 to 35
4 / ADVANTAGES / 36 to 37
5 / REFERENCE / 38 to 39

CHAPTER 1

INTRODUCTION

1.1Project Background

Sometimes electric fan and light is wasting power because of human attitude. Human also mostly demands something that easily to be used without wasting energy. To minimize or to reduce the power usage, this project developed an automatic fan system where fan is controlled by the room temperature and light system where lights are controlled by room light intensity.

1.2Problem Statement

Most human feels the inconvenient about starting the fan manually when the room temperature changes. So, the automatic fan system that automatically switches on the fan according to temperature changes is recommended to be built for solving this problem.

Most human feels the inconvenient about switch on the light manually when the room light intensity changes. So, the automatic light system that automatically switches on the light according to intensity changes is recommended to be built for solving this problem.

1.3Project Objectives

The objectives of this project are to:

  1. Enable the electric fan to automatically switch on-off according to temperature changes.
  2. Enable the light to automatically switch on-off according to room intensity changes.
  3. Develop an automatic fan system and light system that can preview the status of the temperature and the intensity by using Liquid Crystal Display (LCD).

1.4Project Scopes

The system is built using:

  1. Microcontroller as the main controller.
  2. The temperature sensor as the input for the microcontroller.
  3. Relay as the output of microcontroller.
  4. LDR as the input for the microcontroller.
  5. LCD as the preview the status of input.

CHAPTER 2

LITERATURE REVIEW

2.1 Introduction

This chapter reviews about previous system that been developed and has similarities with the automatic fan system and automatic light system plus the components that will be used in developing this system.

2.2 ATmega8 microcontroller

The system is using ATmega8 as the microcontroller. The temperature sensor senses the temperature change and produces the output, the fan is switched on to the range that been set.

There are two thresholds in the program, the minimum temperature and the maximum temperature. “If the temperature is below the minimum temperature threshold, the fan will be turned off. If the temperature is above the maximum temperature threshold, the fan is set to its maximum speed.”

  • Features

• High-performance, Low-power Atmel ®AVR® 8-bit Microcontroller

• Advanced RISC Architecture

– 130 Powerful Instructions – Most Single-clock Cycle Execution

– 32 × 8 General Purpose Working Registers

– Fully Static Operation

– Up to 16MIPS Throughput at 16MHz

– On-chip 2-cycle Multiplier

• High Endurance Non-volatile Memory segments

– 8Kbytes of In-System Self-programmable Flash program memory

– 512Bytes EEPROM

– 1Kbyte Internal SRAM

– Write/Erase Cycles: 10,000 Flash/100,000 EEPROM

– Data retention: 20 years at 85°C/100 years at 25°C(1)

– Optional Boot Code Section with Independent Lock Bits In-System Programming by On-chip Boot Program True Read-While-Write Operation

– Programming Lock for Software Security

• Peripheral Features

– One 16-bit Timer/Counter with Separate Rescale, Compare Mode, and Capture Mode

– Real Time Counter with Separate Oscillator

– Three PWM Channels

– 8-channel ADC in TQFP and QFN/MLF package

Eight Channels 10-bit Accuracy

– 6-channel ADC in PDIP package Six Channels 10-bit Accuracy

– Byte-oriented Two-wire Serial Interface

– Programmable Serial USART

– Master/Slave SPI Serial Interface

– Programmable Watchdog Timer with Separate On-chip Oscillator

– On-chip Analog Comparator

• Special Microcontroller Features

– Power-on Reset and Programmable Brown-out Detection

– Internal Calibrated RC Oscillator

– External and Internal Interrupt Sources

– Five Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down, and Standby

• I/O and Packages

– 23 Programmable I/O Lines

– 28-lead PDIP, 32-lead TQFP, and 32-pad QFN/MLF

• Operating Voltages

– 2.7V - 5.5V (ATmega8L)

– 4.5V - 5.5V (ATmega8)

• Speed Grades

– 0 - 8MHz (ATmega8L)

– 0 - 16MHz (ATmega8)

• Power Consumption at 4Mhz, 3V, 25°C

– Active: 3.6mA

– Idle Mode: 1.0mA

– Power-down Mode: 0.5Μa

2.3 Liquid Crystal Displays

LCD Display (16*2)

Fig.2.1:LCD

Fig.2.2: Back view of LCD

Liquid Crystal Displays (LCD)

An LCD is a small low cost display. It is easy to interface with a micro-controller because of an embedded controller(the black blob on the back of the board). This controller is standard across many displays (HD 44780) which means many micro-controllers (including the Arduino) have libraries that make displaying messages as easy as a single line of code.

Fig.2.3

Testing

Testing your LCD with an Adriano is really simple. Wire up your display using the schematic or breadboard layout sheet. Then open the Adriano IDE and open the example program.

2.4 Fan Controlling System

2.4.1 LM35 Precision Centigrade

Temperature Sensor

Following is the block diagram of LM35 Precision Centigrade Temperature Sensor.

The LM35 series are precision integrated-circuit temperature sensors, whose output voltage is linearly proportional to the Celsius (Centigrade) temperature. The LM35 thus has an advantage over linear temperature sensors calibrated in ° Kelvin, as the user is not required to subtract a large constant voltage from its output to obtain convenient Centigrade scaling. The LM35 does not require any external calibration or trimming to provide typical accuracies of ±1⁄4°C at room temperature and ±3⁄4°C over a full −55 to +150°C Temperature range. Low cost is assured by trimming and calibration at the wafer level. The LM35’s low output impedance, linear output, and precise inherent calibration make interfacing to readout or control circuitry especially easy. It can be used with single power supplies, or with plus and minus supplies. As it draws only 60 μA from its supply, it has very low self-heating, less than 0.1°C in still air. The LM35 is rated to operate over a −55° to +150°C temperature range, while the LM35C is rated for a −40° to +110°C range (−10° with improved accuracy). The LM35 series is available packagedin hermetic TO-46 transistor packages, while the LM35C, LM35CA, and LM35D are also available in the plastic TO-92 transistor package. The LM35D is also available in an 8-lead surface mount small outline package and a plastic TO-220 package.

  • Features
  • Calibrated directly in ° Celsius (Centigrade)
  • Linear + 10.0 mV/°C scale factor
  • 0.5°C accuracy guarantee able (at +25°C)
  • Rated for full −55° to +150°C range
  • Suitable for remote applications
  • Low cost due to wafer-level trimming
  • Operates from 4 to 30 volts
  • Less than 60 μA current drain
  • Low self-heating, 0.08°C in still air
  • Nonlinearity only ±1⁄4°C typical
  • Low impedance output, 0.1 for 1 mA load

2.4.2 ULN200 Liner Integrated Circuit

HIGH VOLTAGE AND HIGH CURRENT

DARLINGTON TRANSISTOR ARRAY

  • DESCRIPTION

The ULN2003 is a monolithic high voltage and high current Darlington transistor arrays. It consists of seven NPN Darlington pairs that features high-voltage outputs with common-cathode clamp diode for switching inductive loads. The collector-current rating of a single Darlington pair is 500mA. The Darlington pairs may be paralleled for higher current capability. Applications include relay drivers, hammer drivers, lamp drivers, display drivers (LED gas discharge), line drivers, and logic buffers.

The ULN2003 has a 2.7kW series base resistor for each Darlington pair for operation directly with TTL or 5V CMOS devices.

FEATURES

  • 500mA rated collector current (Single output)
  • High –voltage output: 50V
  • Inputs compatible with various types of logic.
  • Relay driver application.

 LOGIC DIAGRAM

2.5 Light Controlling System

2.5.1 LDR

(Light Dependent Resistor)

Two cadmium sulphide (cds) photoconductive cells with spectral responses similar to that of the human eye. The cell resistance falls with increasing light intensity. Applications include smoke detection, automatic lighting control, and batch counting and burglar alarm systems.

Applications

Photoconductive cells are used in many different types of circuits and applications.

Analog Applications

  • Camera Exposure Control
  • Auto Slide Focus-dual cell
  • Photocopy Machines-density of toner
  • Colorimetric Test Equipment
  • Densitometer
  • Electronic Scales-dual cell
  • Automatic Gain Control-modulated light source
  • Automated Rear View Mirror

Digital Applications

  • Automatic Headlight Dimmer
  • Night Light Control
  • Oil Burner Flame Out
  • Street Light Control
  • Absence/ Presence
  • Position Sensor

Sensitivity

The sensitivity of a photo detector is the relationship between the light falling on the device and the resulting output signal. In the case of a photocell, one is dealing with the relationship between the incident light and the corresponding resistance of the cell.

Spectral Response

Like the human eye, the relative sensitivity of a photoconductive cell is dependent on the wavelength of the incident light. Each photoconductor material type has its own unique spectral response of the photocell versus wavelength of light.

2.5.2 LED (Light Emitting Diode)

Introduction

A Light-Emitting Diode (LED) in essence is a P-N junction solid-state semiconductor diode that emits light when a current is applied though the device.[1] By scientific definition, it is a solid-state device that controls current without the deficiency of having heated filaments. How does a LED work? White LEDs ordinarily need 3.6 Volts of Direct Current (DC) and use approximately 30 milliamps (mA) of current and has a power dissipation of approximately 100 mill watts (mW). The positive power is connected to one side of the LED semiconductor through the anode and a whisker and the other side of the

Semiconductor is attached to the top of the anvil or the negative power lead (cathode). It is the chemical composition or makeup of the LED semiconductor that determines the color of the light that the LED produces as well as the intensity level. The epoxy resin enclosure

Allows most of the light to escape from the elements and protects the LED making it virtually indestructible. Furthermore, a light-emitting diode does not have any moving parts, which makes the device extremely resistant to damage due to vibration and shocks. These characteristics make it ideal for purposes that demand reliability and strength. LEDs therefore can be deemed invulnerable to catastrophic failure when operated within design parameters.

Figure shows a typical traditional indicator LED. Traditional indicator LEDs utilize a small LED semiconductor chip that is mounted on a reflector cup also known as the anvil, on a lead-frame (whisker).This whole configuration is encased in epoxy which also serves the purpose of a lens. LEDs have very high thermal resistance with upwards of 200K per Watt.

Principle & Mechanism

The essential portion of the Light Emitting Diode is the semiconductor chip. Semiconductors can be either intrinsic or extrinsic. Intrinsic semiconductors are those in which the electrical behavior is based on the electronic structure inherent to the pure material.[5] When the electrical characteristics are dictated by impurity atoms, the semiconductor is said to be extrinsic.[6] See Appendix A for further information regarding the different materials and their characteristics. This chip is further divided into two parts or regions which are separated by a boundary called a junction. The p-region is dominated by positive electric charges (holes) and the n-region is dominated by negative electric charges (electrons). The junction serves as a barrier to the flow of the electrons between the p and the n-regions. This is somewhat similar to the role of the band-gap because it determines how much voltage is needed to be applied to the semiconductor chip before the current can flow and the electrons pass the junction into the p-region.

Fig.: Cross section of a typical semiconductor LED showing the n and p-type semiconductor layers

CHAPTER 3

CIRCUIT DIAGRAM

AND

WORKING

3.1 AT mega8 Microcontroller

Fig.: 3.1: Microcontroller

3.2 Following is the full circuit diagram with connection.

Fig.3.2: Circuit Diagram With Connection

WORKING

This project controls the room light intensity and room temperature. This project depends on two main components. First is the LDR (Light Dependant Resistance) and the second is the LM 35 Temperature sensor.

Room Light Intensity Control

When the room light intensity value is less than the 1ststandard value which is setby push button switches, the LDR give the signal to microcontroller.Microcontroller switched on the supply of 3 LEDs.

When the room light intensity value is less than the 2ndstandard value,microcontroller switched on the supply of 2 another LEDs.

When the room light intensity value is more than 2ndstandard value, microcontroller switched off the supply of 2 LEDs.

When room light intensity value is more then the 1ststandard value, microcontroller switched off the supply of 3 another LEDs.

This way, the room light intensity is controlled by this project.

Room Temperature control

When the room temperature value is getting high from standard value, microcontroller switched on the supply of Fan.

When the room temperature value is getting low from standard value, microcontroller switched off the supply of Fan.

This way, the room temperature is controlled by this project.

3.3 Power Supply circuit

Fig.3.2: power supply circuit

This figure showed how to give the supply to this circuit.

Our circuit needs 5v DC supply to operate. Therefore we use power supply circuit.

This circuit includes following components……

1)Step-Down Transformer

2)4 Diode (for make bridge rectifier)

3)1 Capacitor (1000 microfarad)

4)1 Capacitor (47 microfarad)

5)7805 Voltage Regulated Circuit

We need step-down transformer so 230V AC supply is given to step-down transformer. Transformer gives us 12V AC. This 12V is given to bridge rectifier for rectification. After rectification we have 12V DC. This 12V DC has some AC components so we use Capacitors. It connected in parallel. It absorbs AC components from 12V DC. Then this 12V pure DC is given to 7805 Regulated Power Supply circuit. This circuit gives us 5V DC for the supply of our main circuit.

Project Model

CHAPTER 4

Advantages

4.1 ADVANTAGES

Circuit is simpler in design.

We can use Solar panel as power supply.

The use of fan switch in fans can be avoided.

Power saving.

Temperature variations can be easily tracked down.

Less maintenance.

Easily repairable. Since there is no complex circuitry setup involved.

Low installation cost.

CHAPTER 5

REFERENCE

Reference:-

1