Final Year Project Report Book

DESIGN AND CONSTRUCTION OF A 3-PHASE AUTOMATIC POWER CHANGE OVER SWITCH.




BY








{YOUR NAME}





BEING THE A SEMINAR SUBMITTED TO THE DEPARTMENT OF ELECTRICAL AND ELECTRONIC ENGINEERING, 
{YOUR SCHOOL NAME}







IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE AWARD OF HIGHER NATIONAL DIPLOMA (HND) IN ELECTRICAL AND ELECTRONIC ENGINEERING.

..........................................................................

ABSTRACT
This project presents the construction of automatic change over switch in between the 3-phase electrical power supply. The purpose of this is to isolate human means of changing electrical power supply from one phase to another which not only dangerous for unprofessional or untrained personnel. Changing from one phase to another involves removing the cut-out fuse from one phase and inserts it into another available phase which not only takes time but could also leads to electrocution of the personnel doing such if his/her hand mistakenly touches live wire.
Every home in Nigeria or outside is connected to the 3-phase power supply but could only make use of one phase at a time which therefore requires switching over to other phase if the previous is interrupted.
Therefore, this project will solve the manual change over switch being operated by human being into automated change over switch which will reduce the stress being encountered and minimized the danger of electrocution involves.
The device is built around transformer, relay switch, contactor and NE 555 timer IC.
Keywords: transformer, 3-phase, electrocution, contactor.
............................................................
The project report above is in both MS word for your Editting and in PDF

Price for complete report = #2,000
To: Wema bank, A/c:0234957770.
After payment it will be sent to you on WhatsApp.
Call/WhatsApp: 07063253911


CONSTRUCTION OF 4600mAh POWER BANK


BY

  • OBANDE JOSEPH .B.       :D141EE039

  • ALI SULIYAT IYABODE  :DI41EE002






BEING A FINAL YEAR PROJECT SUBMITTED TO THE DEPARTMENT OF ELECTRICAL AND ELECTRONIC ENGINEERING, 

THE POLYTECHNIC, ILE IFE, OSUN STATE.




IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE AWARD OF NATIONAL DIPLOMA IN ELECTRICAL AND ELECTRONIC ENGINEERING.

UNDER THE SUPERVISION:

OF 


ENGR. DR, D.O EXCELLENCE

JUNE, 2015

CERTIFICATION

This is to certify that the project work titled “CONSTRUCTION OF 4600mA POWER BANK” was done by OBANDE JOSEPH BENEDICT (D141EE039) AND ALI SULIYAT IYABODE (D141EEO22) of the Electrical and Electronic Engineering department under my supervision. 

I hereby recommend it for academic advancement.


_________________                            ________________

Engr. Excellence, D.O     Date

Supervisor


_________________   _________________

Engr. Olatunbosun, M.E     Date

   Head of Department









ACKNOWLEDGEMENT

All Glory be unto God Almighty for making it possible for us to gain admission for the first path of education (ND) in this able institution (THE POLYTECHNIC, ILE IFE) and who have made us scaled through the hardship and tough time. He has been by our side from the first day we step our foot on this great institution. We give all our appreciation to you Almighty God.

We acknowledge with great gratitude to our humble and well respected supervisor, the person of ENGR DR D.O EXCELLENCE for his tireless help and effort. We pray that God will increase his strength.

And also to the effort of our HOD & lecturers ENGR. M.E OLATUNBOSUN, MR ADEDOYIN AKOLADE, I pray that God almighty will reward their hard work. we thank you all for your support throughout this program and we pray that our wonderful and blessed savior will never leave nor forsake you rather He will always continue to meet you at the point of all your needs.

And also we appreciate the effort of MR. KAREEM AYODEJI, for his effort and attention giving to us during the project works, he has been a source of knowledge during the practical. And it is our prayers that God will not forsake him, He will continue to provide for all his needs. We can’t forget the impact of MR UTHMAN BADRUDEEN.

Also to our family; MR & MRS. OBANDE BENEDICT, MR. EMMANUEL OBANDE, MR PETER NKEM, MR CLEMENT OBANDE, and MR & MRS ALLI, MISS FOLASHADE ALLI, MR ALFRED we say a big thanks to you all.

Finally, we appreciate all our course mates and the entire staffs of The Polytechnic, Ile Ife for their assistance, love and understanding towards the successful completion of our National Diploma program. We say a big thank you all.




DEDICATION

The project is dedicated to GOD Almighty for making it possible for the completion of this final year project work which is really a very big challenge to us.

Also for making it possible for the successful completion of this National Diploma (ND) program in The Polytechnic, Ile Ife in peace, healthiness and for the great achievement that we cannot mention.

And also to our great parent for their caring, who have passion for education, who also led us through the right path. And also for their moral, financial and spiritual support giving to us during and after this final year project.

 We pray that they will reap the fruit of their labour in JESUS name. Amen.

I pray that they will, live long to witness our greatness. Amen.

Finally we want to dedicate this final year project work to all our friends for their advice during our time in school. Thank you all.




ABSTRACT

This project involves the construction of 4600mAh power bank, it consists of three different modules which are; power storage module, battery charging module and phone charging module. All these modules consist of different circuit in other to perform their main functions.

The power storage module consist of pen batteries of 1.2V with 4600mAh current rating which are all connected in series in other to increase the battery voltage from 1.2V to 10.2V require to power the phone charging circuit.

The battery charging module is responsible for the restoration of energy to the power storage module (battery) after it has been used to charge mobile phones.

In other to ensure that the device is portable to be carry all around, the battery charging module (i.e. battery charger) has been isolated from the circuit, therefore it has reduced the bulky component from the device (power bank) and there is connecting port between the power charging module and the power bank (power storage & phone charging module) through which it can be connected in other to recharge the battery.











CHAPTER ONE

  1.      INTRODUCTION

Power bank are portable device comprised of a special circuit that control power flow. They allow the storage of electrical energy (i.e. deposit it into the battery bank) and then later use it to charge any mobile device (i.e. withdrawn it from the battery bank). 

Power bank is also called “plug in battery, external battery and charging battery” of the digital products. Its definition is convenient and easy to carry large-capacity portable power. Power bank can simple be define as a power storage/energy reservoir for a secondary cell or a rechargeable battery. It is a third party charger that offers power to your mobile phone when the need arises.

 Power banks have become increasingly popular as the battery life of phones, tablets and portable media player is outstripped by the amount of time we spend using them each day. By keeping a battery backup close by, you top up your device(s) while far from a wall outlet. Power banks are good for almost any USB-charged devices. Cameras, MP3 player, mobile phones, tablets etc. as long the power bank is charged. Most commonly power bank will have a dedicated input sockets for receiving power. This power can come from a USB sockets on your computer, but may charge faster when using a wall socket adapter. In most rare occasions , power bank can  use the same socket for input and output, but this is rare and should not be assumed of any power bank, as trying to force power into an output can damage the battery.

With the rapid development of global economy, people continued to carry more portable electronic products, as mentioned earlier, which are drained or discharged as a result of longtime uses.

Therefore power bank provides the means of recharging then without the needs of waiting for electric power supply be restored. Power bank are of different size and capacities e.g. 200mAh, 3300mAh, 4600mAh etc.


1.1   SIGNIFICANCE OF THE PROJECT

The power bank is an electronic device which produces electric energy for consumption when charge, it is an external charging battery for mobile phones. 

The benefit of these design include;

  • Charging of mobile phone when it runs out of battery.

  • It is portable, is neither heavy nor inconvenient to carry.

  • It has a multiple socket for all kinds of phone.

  • It can charge all kinds of phone.

  • It can run for several hours and keeps feeding mobile phones.

  • The power bank is a very affordable tool.


1.2   AIMS AND OBJECTIVE

This design (Power bank) is an electronic device aimed at achieving the following;

  • To construct a power bank that will be able to charge all types of mobile phone devices.

  • A device that is capable of supplying 4600mAh current.

  • A device with short circuit protection.

  • A power bank that as over- charging protection.

  • A device that the battery is rechargeable.

1.3 SCOPE AND LIMITATION

This project is the design and construction of 4600mAh power bank for use in residential homes, commercial homes, offices etc, to charge mobile phones.

The limitation of these design is that it can only be used for the charging of mobile phone device and it should not in any case used to charge other high current consumption device such as laptops, car batteries etc.

















CHAPTER TWO

  1. LITERATURE REVIEW

2.1 BACKGROUND OF STUDY

Power bank charging equipment specifically designed for the mobile phones of majority of large power consumption. This device is suitable for the system on all smart phones, such as iOS, Androids, Blackberry OS and Symbian.

With an increased number of features, mobile devices like smart phones, tablets etc are requiring more power. To extend their operating life, manufacturing try to use bigger batteries but are limited because of the weight and size. To provide users additional power when their devices are running low, many users are learning to relay upon power banks, a portable energy source that can be carried in a pocket or backpack. Power banks store energy in an internal lithium Ion battery and can charge the mobile devices.


2.2   HISTORY OF POWER BANK

Power bank previously known as mobile power which comes into existence between (2001 –2003) as a result of student carrying out practical knowledge on providing another means of charging their cell phones.

Mobile power (power bank) is essentially a charger, and it first appeared in Lasvegas International Consumer Electronics Show in 2001, a student pieced a control circuit with a few AA batteries representing the portable external battery charger officially born.

The formation stage of the concept of market (2004-2006): victories put a large amount of money to launch the engine compartment named mobile power, and this event marked the untimely the early throes and started their own prototype mobile power by only product concept info the market concept stage.

The slow market development stage (2006-2009): the representative event was that some capable of manufacturing enterprises entered the field of mobile power production, which means that mobile power has finally established its market image as a new product, thereby going into the track of normal development, and to see the growth rate of the steady expansion of market capacity.

It became globally recognized in 2004 when some electronic companies produce it as a special product.


2.3   MARKET GROWTH PHASE

The popularity of power bank began in 2009, during this period, the domestic e-commerce rises (i.e. its sales) and also the rise of smart phones marks the event that gradually establishes the product.

A land mark event from slow growth to the rapid growth was in 2007 when Apple introduced the Iphone (a style product design, with powerful software features and high power consumption). Power bank has made a lot of impacts both on economy and people that went on vacation or tourism so as to keep their mobile device working for longer period of time.





CHAPTER THREE

3.0 METHODOLOGY:

The power bank system consists of three different modules; charging module, power storage module, and mobile charging module, this are represented in the block diagram as shown below:





3.1 CHARGING MODULE

Charging Module consists of all the components required to ensure that the battery (power storage) were recharged after it has been drained or discharged in the process of mobile phone charging.

This module contain circuit diagram which responsible to ensure the automatic charging so as to prevent the battery from being over charged.

C:\Users\user\Desktop\CHARGING MODULE 2.jpg

3.1.1 CIRCUIT OPERATION OF CHARGING MODULE

Transformer TR1 is a step down transformer that convert the 230V AC supply to 12V AC supply at its output, diode D1...D4 (i.e. D1, D2, D3 & D4) are rectification diode which convert 12V AC (Alternating Current) supply to full wave rectified DC (Direct Current) supply, capacitor C1 is an electrolytic filtering capacitor which remove any AC ripples present in the rectified DC voltage output.

Resistor R1 is of a fixed resistance value which is used as a smoothing resistance for the Potentiometer P1 (variable resistor) which bias the Base terminal of the transistor T1, resistor R2 is a load or collector resistance for transistor T1 and also as a smoothing resistor for the potentiometer P2 which also supply the biasing current to the base terminal of transistor T2.


Transistor T1 and T2 are NPN bipolar junction transistors (BJT), the two transistors are used to power the relay switch so as to control the charging of the battery. The DC rectified output is connected directly to the common terminal of the relay switch and it is also used as a positive power supply for the relay switch. The battery positive terminal is connected to normal open(NO) of the relay switch so that when the battery voltage fall below the setting value the relay is triggered and thereby change it to normal close (NC) and the battery start charging.


Diode D5 is a protecting diode that prevents back flow of electric current as a result of instantaneous tripping on and off of the relay switch coil which induces brief increase of voltage when tripping off and the diode which is reversely connected across the relay switch power terminal allow the voltage to drain out slowly. Diode D6 prevents back flow of electric current to the battery.


3.1.2. SETTINGS OF THE CHARGING WINDOW FOR THE BATTERY

To ensure that the battery is prevented from being over charged, the range/window at which the battery is to start charging and stop charging need to be set and this is done by disconnect the DC rectified output from the circuit and used the battery at its fully charged condition to serve as input to the circuit (when the transformer has been removed) and also connection was made between the negative terminal of the Diode D6 and the relay switch terminal.

C:\Users\user\Desktop\CHARGING MODULE SETTING.jpg

The Potentiometer P1 and P2 are set to certain equal range, P2 is used to set the maximum charging voltage of the circuit and it is varied or tuned till the relay switch trip ON while P1 is used to set the lowest or minimum charging voltage and varied until the relay switch also trip OFF therefore the operating window for charging has been set.

After this setting the battery is removed and connects the circuit back to normal wirings.

3.2 POWER STORAGE MODULE

This consists of rechargeable pen batteries (AAA size), each of the battery has current capacity of 4600mAH with voltage of 1.2 volts and they are all arranged in series to give the required voltage of 12V for the Mobile charging module.

+vebattery symbol-ve

This battery is recharge by the charging module when it is drained or discharged as a result of long time use.

3.3. MOBILE CHARGING MODULE

This module consists of the circuit responsible for the controlling of the current required to charge the mobile device to its full capacity. It gets its power supply directly from the power storage module. It has 40mA charging current at its output.

http://www.electroschematics.com/wp-content/uploads/2009/12/travel-cell-phone-charger.jpg

When power is applied to the circuit through S1, transistor T1 conducts and green the LED lights. When T1 conducts T2 also conducts since its base becomes negative. Charging current flows from the collector of T1, in other to reduce the charging voltage to 4.7 volts, a Zener diode D2 is used. R1 is the base biasing resistor for transistor T1, capacitor C1 filters ripples or noise that may present in the circuit, R2 is the load resistor for transistor T1 and which also determines the collector current output, R3 is biasing resistor for transistor T2 (PNP), R4 is the output load resistance and current limiting resistor for Zener diode while R5 is the limiting resistor to the mobile phone charging point.


3.4 LIST OF MATERIAL USED

3.4.1 EQUIPMENT USED

  • Breadboard.

  • Soldering iron.

  • Lead

  • Plier

  • Cutter

  • Wire stripler

  • Desoldering pump

  • Electrician knife

  • Earthing clip.

  • USB connector

  • Vero board.

  • Battery casing

  • Pattrex casing

  • Bolt & nut screw

  • Terminal connector.

3.4.2 COMPONENT USED

  • Transformer.

  • Diode

  • Resistor

  • Capacitor

  • Relay

  • Zener diode

  • Variable resistor

  • LED

  • Battery

  • On/Off switch.





3.4.3 COMPONENT DESCRIPTION

Below are the descriptions of the component used in this project work with their respective circuit symbols.

4.1.1 Transformer: This is used to step down the 230V AC power to 15V AC power supply. There are two types; step down transformer and step up transformer. It has input as primary winding and output as secondary winding.

transformer symbol

Two coils of wire linked by an iron core. Transformers are used to step up (increase) and step down (decrease) AC voltages. Energy is transferred between the coils by the magnetic field in the core. There is no electrical connection between the coils.

4.1.2 Diode (1N4007, 1N4148): A device which only allows current to flow in one direction, 1N4007 is rectification diode which does the conversion of AC supply DC supply while 1N4148 is mainly used as a protecting diode.

Anodediode symbolCathode

4.1.3 Capacitor: There two types; electrolytic and non-polarized, capacitor stores electric charge. This type must be connected the correct way round. A capacitor is used with a resistor in a timing circuit. It can also be used as a filter, to block AC signals but pass DC signals.

                       polarised capacitor symbol                     capacitor symbol

           Electrolytic or polarized capacitor           Non-polarized capacitor

4.1.4 Resistor: There are two types; fixed and variable resistor, they are mainly used to limit the flow of current to any other component or devices.

                                             potentiometer symbol      rheostat symbol       resistor symbol

        Fixed resistor                                         Variable resistor                                                       

4.1.5 Transistor: Transistor amplifies current. It can be used with other components to make an amplifier or switching circuit. There are two types; NPN and PNP.

              PNP transistor symbol                                                                              NPN transistor symbol   

                          PNP                                                                             NPN                                                                                            


4.1.6 Zener diode: Is a special diode which is used to maintain a fixed voltage across its terminals. It is reversely connected in other to act as a voltage regulator but when it is forward bias it act as a normal diodes.

Anodezener diode symbolCathode








CHAPTER FOUR

4.0 IMPLEMENTATION, TESTING AND EVALUATION.

4.1 IMPLEMENTATION

After the different modules (charging module, Power storage and Mobile charging module) had been constructed and tested for normal working condition they were enclosed in a plastic casing as shown in the subsequent pictures below. 

C:\Users\user\Desktop\IMG-20150422-WA0001.jpg

Picture during construction

C:\Users\user\Desktop\IMG-20150422-WA0002.jpg

Picture during construction and soldering

C:\Users\user\Desktop\Photo0065.jpg

Picture of the different modules

C:\Users\user\Desktop\Photo0066.jpg

Enclosed plastic case with charging indicators and switch

4.2 TESTING & RESULT

When the power supply plug is connected to the 240V AC supply and the power switch is turn ON the red indicator lights up showing that electricity has been supplied to the circuit and the battery charging module start charging the battery when the battery has fully charged the relay will trip off thereby preventing the battery from being over charged.

The power bank has USB connector interface through which the mobile device can be connected for charging when the phone charging module is turned ON.

The power bank has the ability to charge two mobile devices at the same time 

After the overall construction the device (Power bank) was allowed to charge for some times in other to restore the battery to its fully charged level. 

4.3 COST EVALUATION AND ANALYSIS

4.3.1 COST ANALYSIS OF COMPONENTS AND MATERIALS USED

S/N

NAME OF COMPONENT

QUANTITY

UNIT PRICE

TOTAL

1

Transformer (15V, 2A)

2

800

1600

2

Relay switch

4

100

400

3

Breadboard

2

500

1000

4

Soldering iron

1

1000

1000

5

Rechargeable pen battery

8

200

1600

6

Battery holder

6

100

600

7

Connector holder

6

100

600

8

Vero board

3

100

300

9

Plastic casing

1

1000

1000

10

Soldering lead

1 roll

400

400

11

Jumpers

4roll

100

400

12

Transistors

20

100

2000

13 

Resistors 

20

10

200

14

Capacitors

20

50

1000

15

Variable resistors

10

50

500

16

Diodes

20

30

600

17

Battery clip

8

30

240

18

Power cable

1

80

80

19

USB connector

1

50

50

20

USB phone charger

1

300

300

21

ON/OFF switch

4

50

200

22

LED (red, green)

10

10

100

23

Power plug

1

80

80

24

Flexible wire 

4yards

50

200

25

Hi watt battery

1 pack

450

450

26

Bolt & nut

10

20

200




TOTAL

13,500


























CHAPTER FIVE

5.0. CONCLUSION RECOMMENDATION AND REFERENCES

5.1. CONCLUSION

Power bank has made a lot of impact both on human’s life as a result of the fact that people find it difficult to do away with their mobile devices switch off or drained out while they are away from their home or offices or which can be as a result of outage or interrupted AC power supply.

It has also improved the economy tremendously as more people buy it as a necessity for the purpose of charging their mobile devices.

5.2. RECOMMENDATION

This project is recommended for use in office or at any locations for the charging of mobile devices when there is interruption of electric power supply and should not in any case use to charge high consuming devices like laptop computer

5.3. REFERENCES

5.3.1. S.CHAND, (2009). Basic electronics textbook: definition of components, page 105.

5.3.2. www.circuitstoday.com, 

5.3.3. www.diy.com


    A

PROJECT PROPOSAL ON THE DESIGN OF SMOKE DETECTOR ALARM

BY


AMUSA ABISOLA MARY : DI41EE033

 


SUBMITTED TO THE DEPARTMENT OF  ELECTRICAL/ELECTRONICS

ENGINEERING.

THE POLYTECHNIC ILE-IFE, OSUN STATE.


IN PARTIAL FULFILMENT FOR THE REQUIREMENT OF THE AWARD OF NATIONAL

DIPLOMA IN ELECTRICAL/ELECTRONICS ENGINEERING.

JULY 2015.         

 CERTIFICATION

I AMUSA ABISOLA MARY, declare that this work was done by me and has never been presented

elsewhere for the award of a degree. I also hereby relinquish the copyright to The Polytechnic,

Ile-ife, Osun state. 

 (Name of student)               (Name of H.O.D)

…………………………..                …………………………

(Signature and Date)       (Signature and Date)

…………………………            ……………………………….

 (Name of Supervisor)

…………………………. 

(Signature and Date)

………………………………..

  


                        









                                             DEDICATION

 This  project is dedicated to Almighty God, the alpha and omega in which the successful completion

of the program is due to His mercy. To my Daddy Mr Tajudeen Amusa. To my respected Mum;

Mrs Christiana Amusa and to my able sisters. May Almighty God let them reap the fruit of their

labour (Amin) 

                  









              










                                    ACKNOWLEDGEMENT

 I give my humblest gratitude to Almighty God, the most merciful and most gracious for the privileged,

grace and strength which He has afforded me to partake of this great experience.

To my parents Mr and Mrs Amusa through whom it has been possible for one to experience this life

and have seen to my well being this far. I say a big thank to you with warmest love.

The sincere thanks goes to my esteemed supervisor Mr Kareem Ayodeji who despite his tight schedule

has always attended to my need for the project work. I am thanking him for his co-operation, correction

and scholarly advice, who challenged me to work very hard. I cannot but remember my Sisters for

their financial assistance,  concern and endless advice. I will like to thank the HOD of the department

Engr. Olatunbosun M.and all the lecturers in electrical/electronics engineering department, to my

colleagues and classmate a big kudos for the spirit of sharing and understanding. Finally, I will like

to thank my friends and all other well-wishers who have contributed on their own way to this success,

may Almighty God bless everyone "Amen" 

                    

ABSTRACT

Fire is a disaster that can strike anywhere and can be very destructive

A method to detect smoke and fire would allow the authorities to detect and put out the fire before

it becomes out of control.

A good fire escape plan will only be successful if we know early enough that a fire has started.

Fire may build rapidly and spread toxic gases and blinding smoke throughout the home or it may start

small and smoulder slowly, all the while emitting deadly toxic gases.

Most fatalities in house fires occur at night and are caused by breathing in smoke and toxic fumes,

rather than by burns. Smoke and flames can quickly overcome residents particularly when they are

asleep.

The nose goes to sleep when we sleep. By detecting smoke, a smoke or temperature detector alarm

gives early warning of fires and alarm to wake you up.










TABLE OF CONTENT

Title page............................................................

Abstract.................................................................

Table of Content....................................................

LIST OF FIGURES..................................................

Figure 2.1..............................................................

Figure 2.2..............................................................

Figure 2.3..............................................................

Figure 2.4.................................................. .. .........   

Figure 2.5...............................................................

Figure 2.6...............................................................

Figure 2.7...............................................................

Figure 2.8...............................................................

LIST OF TABLE......................................................

Table 3.1................................................................

CHAPTER 1............................................................

INTRODUCTION....................................................

1.0 Terminology....................................................

1.1 Heat Detector..................................................

1.2 Smoke Detector..............................................

1.3 Smoke Alarm..................................................

2.0 Types of Smoke..............................................

2.1 Photo electric Smoke Detector.....................

2.1.1 Light scattering Smoke Detector........................................

2.1.2  Light Obscuration ...............................................................

2.2      The Ionisation Smoke Detector..........................................

3.0     Limitation of the project.......................................................

CHAPTER 2

LITERATURE REVIEW..............................................

CHAPTER 3..............................................................

3.0 METHODOLOGY.........................................................

3.0.1 Component Analysis...............................................

References.................................................................















CHAPTER ONE

INTRODUCTION

  1.    Terminology

There are essentially three different types of devices used for the detection of heat or smoke.

The following definitions are intended a brief explanation of the application of each device within the

context of residential development.

  1. Heat Detector

This refers to a device that is designed to operate at a pre-determined temperature or rate of temperature

rise. These devices are required within suites and other specific locations throughout a multi-family

residential (apartment) building. 

The purpose of this device is to alert the residents of both the suite and the building of a fire occurrence.

This device can be activated by heat only and it is usually connected to the building fire alarm system.

  1. Smoke Detector

This refers to a device that is designed to operate when the concentration of airborne combustion

products exceeds a pre-determined level. This device activates more quality than heat detectors and

it is required In an area of multi-residential buildings where hazardous materials may be stored or used.

They may also be used as a substitute for heat detector under specific  circumstances. Like the heat

detector, the purpose of the device is to alert the residents of the building of a fire occurrence through

connection to the building fire alarm system.





  1. Smoke Alarm

This refers to a device which is a combination of smoke detector and an audible alarm. It is designed to

sound an alarm within the room or suite in which it is located upon the detection smoke/fire within that

room or suite.

These alarms are activated when smoke either interferes with the ability of ionized air to conduct an

electrical current or scatters light in a way which affects a photo-sensitive plate. This causes an alarm

within the device to sound. 

With early detection, small fire can be extinguished before they spread and residents are given enough

time to escape from larger ones. This device is required in all residential unit including single family

and two family dwellings. With the alarm built into the device, it is intended to alert only the occupants

of the suite in a multi-family or all the occupants in a dwelling unit.

  1.   Types of Smoke Alarm

There are basically two types of smoke detector alarms. They are properly explained below.

2.0.1  The Photo-Electric Smoke Detector  

This is a sensor that is used to initiate a fire alarm when smoke reduces the light received by the

photo-electric cell in a device containing a light source. It is further sub-divided into two, they are

 2.0.1.1 Light Scattering Smoke Detector

  A Light Emitting  Diode (LED) sits on the other side of the partition within the chamber. Smoke

particles entering the chamber defects some of the light rays into the Light Dependent Resistor (LDR).

The LDR generate a current when exposed to light and if the current reaches a certain level, the detector

alarms.

2.0.1.2  Light obscuration

In a projected beam detector, alarms are generated by diffusing the projected light beam by a specific

percentage of obscuration. Total beam blockage generally result in trouble signal.

2.0.2  The Ionisation Smoke Detector

This contains a small amount  of radioactive material encapsulated in a metal chamber. Ionizing

radiation develops a slow but steady electrical current. Smoke particles entering the chamber disrupt

the current and trigger the detector alarm.

Which type is better?

Unfortunately there is no simple answer, they both work on different principles and as such they,

respond differently to conditions. Photo electric detector responds faster to slow, smouldering flames.

In this design, my main consideration is based on photo electric smoke detector.


3.0 Significance of the smoke detector alarm.

According to the U.S fire administration, more than 3,000 people died from fires in 2008 with

84 percent of fatal fires happening in homes and other dwellings.

Unless you see a fire start, you can only find out  there is fire if you are awake to smell the smoke.

If you happen to be asleep, a smoke detector is probably the only way to save your life and the lives

of everyone sleeping in your home.

4.0  Limitation of the project

The drawback of this project is listed as follows:

1.   Some of the components to be used needs to be booked down before they are made readily available

and this tends to increase the time frame of the project.

2.   Smoke detector are not recommended for kitchens, bathrooms, or garages where cooking fumes,

steam or exhaust fumes could result in false alarms.

3.    It cannot be install in an attic or other unheated spaces where humidity and temperature changes

could affect the alarm's operation.


CHAPTER 2

LITERATURE REVIEW

2.0 Background of Smoke Detector 

The smoke detector is a major element of a joint project among the Consumer Product Safety

Commission, the Congressional Fire Services Institute, the United State Fire Administration and the

National Fire Protection Association and many other organisation are also project participants and have

a strong interest in the results of the survey if smoke and temperature detector.

In 1989, approximately 85 percent if U.S residence are estimated to have installed smoke detectors,

although residential structural fire deaths fell about 25 percent between 1980 and 1990, the U.S still

has one of the highest fire death rate in the industrialized world.

About 65 percent if home fire deaths occur in the small fractions of homes without  smoke detectors.

Further, there us a serious concern that disabled or non-working smoke detectors are so

common that they are preventing the U.S from achieving the full potential to increase fire safety from

smoke detectors.

In 1987, about 35 percent of residential fire deaths occurred in homes that did have detectors.

In addition to homes that did not have smoke detectors installed, a previous study suggested that

one-third of the household that had detectors and experience a fire had non-working smoke or

temperature detectors.

The smoke detector was done to fill a need for new field data on the proportion if installed smoke

detectors that are working.

Smoke and temperature detector alarm are intended to sound an alarm when they sense smoke rise,

so the smoke detector should be placed near the ceiling or directly onto the ceiling. It is usually food

to ensure that smoke detector is placed at every level of the home, inside each bedroom and outside

each sleeping area. It is also good to follow the manufacturer's recommendation for the installation

of the smoke and temperature detector alarm.

  2.1   List of Components

  1. Resistor 470 ohms

  2. Resistor 33kilo ohms

  3. Resistor 2.2kilo ohms

  4. Resistor 47kilo ohms

  5. Resistor 560 ohms

  6. Variable Resistors 100kilo ohms

  7.  Light Dependent Resistor (LDR)

  8. Diode (IN4001)

  9. Electrolytic capacitor 10uF

  10. Transistor BC548

  11.  Transistor BC558

  12. Transistor TIP41C

  13.  Capacitor 0.04uF

  14.  Intergrated Circuit(IC) 555 Timer

  15. IC Socket 555 Timer

  16.  Buzzer

  17.  Switch

  18.  Jumpers

  19.  Relay

  20.  Bridge diode

  21.  15V Transformer

  22.  Choke resistor 3.3ohms 10watt

  23.  Patrex

  24.  Vero board

  25.  Lead

2.2 COMPONENT ANALYSIS

This entails the basic function of some of the component used and their circuit diagram.

2.3 BATTERY

This is an electrolytic device that stores electrical energy.

 Figure 2.1  Battery structural diagram

2.4  RESISTOR

This is a component that oppose the flow if electric current in a circuit.

Fig 2.2(a) Schematic symbol of a resistor

Fig 2.2(b) Schematic structure of a variable resistor


2.5  DIODE

This is a component that allows the flow of current in one direction.


 





 Figure 2.3   Diode schematic symbol

2.6  CAPACITOR

This is a component that helps in the filteration of impurities. Its other function is that it also helps in the storage of electrical charges.


Figure 2.4   Capacitor schematic symbol


2.7  TRANSISTOR

This is a component that helps in the amplification of voltage, current and frequency.

The diagram in Figure  illustrate a N-P-N Transistor, while Fig  illustrate a P-N-P  Transistor.

Fig 3.2(a) Schematic symbol of an N-P-N Transistor

                Fig 3.2(b) Schematic symbol of a P-N-P Transistor


2.8  LIGHT EMITTING DIODE (LED)

This is a component that serves as an indicating device.


                Fig 3.5 Schematic symbol of LED

2.9  THERMISTOR

This is a component that works base on the principle that the higher the light intensity, the lower the

resistance and vice versa




2.10  BUZER

This is a device that converts electrical signal to sound. It is usually an output device because it

produces sounds.

2.11 SWITCH

This is a device that helps to make or break the connection in a circuit

                  Fig 3.8 Schematic symbol of a switch

2.12 LIGHT DEPENDENT RESISTOR (LDR)

This is a component that have a (variable) resistance that changes with the light intensity that falls in it

2.13 INTEGRATED CIRCUIT (IC)

This is a semiconductor wafer on which thousands or millions of tiny resistors, capacitors and transistors

are fabricated.

2.14  TRANSFORMER

A transformer is a device that step-up or step-down voltages.

Fig 3.9 Schematic diagram of a transformer

2.15  RELAY

 Relay  are switches that open and close circuits electromechanically and electronically.

2.16 BRIDGE DIODE

A bridge diode is an electrical device that converts alternating current(ac), which periodically reverses

direction, to direct current(DC) , which flows in only one direction.


CHAPTER 3

3.0  METHODOLOGY

The key advantage of smoke detectors is their ability to identify a fire while it is still in its incipient.

As such, they provide addedopportunity for emergency personnel to respond and control the developing

fire before severe damage occurs. They are usually the preferred detection method in life safety and

high content value applications. The disadvantage of smoke detectors is that they are usually more expensive to install, when compared to thermal sensors, and are more resistant to inadvertent alarms. However, when properly selected and designed, they can be highly reliable with a very low

probability of false alarm. Table 3.1 shows the list of component, the quantity to be used and their

individual price.

Table 3.1

  S/N

COMPONENTS

QUANTITY 

AMOUNT

1

Resistor 470 ohms

4

40

2

Resistor 33kilo ohms

1

20

3

Resistor 2.2kilo ohms

1

20

4

Resistor 47kilo ohms

1

20

5

Thermistor

1

100

6

Resistor 560 ohms

1

20

7

Light Dependent Resistor (LDR)

1

20

8

Diode (IN4001)

2

20

9

Electrolytic capacitor (10microfarad 16V)

1

20

10

Transistor BC548

1

20

11

Transistor BC558

1

20

12

Variable resistor

1

20

13

Transistor EC558

1

20

14

Capacitor 0.04microfarad

1

20

15

Integrated circuit(IC) 555 Timer

1

50

16

IC Socket 555 Timer

1

50

17

Buzzer

1

300

18

Jumpers

1 roll

300

19

6V Rechargeable battery

1

900

20

Light Emitting Diode (LED)

3

30

21

Ferro board

1

120

22

Patrex casing

2

1000

23

Capacitor 0.01microfarad

1

20

24

Switch

1

20


TOTAL


2420

Miscelleneous Expenses, that is, 10% of the total cost of the materials which is

2420×10÷100= 2420×0.1=242

Addition of the total cost and the miscelleneous expenses=2642.





FIGURE 3.9 SMOKE  DETECTOR CIRCUIT DIAGRAM


3.0.2 FUNCTION OF THE CIRCUIT

The circuit diagram in figure 1.1 is the smoke detector circuit.

The supplied voltage of the circuit is 6V DC battery.

LIGHT DEPENDENT RESISTOR (LDR): This works base on the principle of light intensity. The

lower the resistance, the higher the light intensity and the higher the resistance, the lower the light

intensity. When smoke now pass in between the control LED 2 therefore the resistance of the LDR

will increase thereby sound the speaker.

3.0.3 OPERATION OF THE CIRCUIT.

When the main power switch(SW1) is turned on, the LED 1 is turned on thereby indicating that there

is power supply throughout the circuit. LDR and Resistor R8 forms a voltage divider(for smoke detector)

. Diode D1 prevents back flow of electric current, R2 is base resistor for transistor T1, Capacitor C1

filters ripples within the biasing voltage for the LDR

When there is no sensing activities from both sensors, the transistor T2 is properly biased thereby

holds the reset terminal pin(4) high and prevent the Integrated Circuit (IC)  from producing sound

output but when there is sensing activities, T1 is forward biased while T2 is reversed biased thereby

the reset terminal pin(4) is drawn to zero(0) volt and the IC produce sound output indicating there is

fire or smoke outbreak.








FUNCTION OF THE CIRCUIT

The circuit Fig 3.10 is a car battery charger circuit and it is incorporated into the smoke detector alarm

circuit. The reason for its incorporation is to charge the 6V battery that powers  the smoke detector

alarm circuit. This inturns recycle the operation of the battery.



C:\Users\BADMUS\AppData\Local\Microsoft\Windows\INetCache\Content.Word\power circuit.jpg



OPERATION OF THE CIRCUIT

The circuit in Fig 3.11 is powered by a 15V transformer. The capacitor C1 is the capacitor that filters

the ripples in the circuit. This circuit works based on the principle that when there is power in the circuit,

the LED1 remains on and the relay works based on its normal principle but when the battery is low,

the transistor triggers the relay and the relay normal open becomes normal close and the normal close

of the relay becomes normal open and the LED2 is on which indicates that the battery is charging.





CHAPTER 4

4.0  DISCUSSION

Smoke detector incorporated with an alarm system that can help to avert fire occurrence. It does not

really keep the fire from occurring but gives a warning of a fire occurrence.

A charging circuit is also is also incorporated and the function of the charging circuit is to recharge the

6V that powers the smoke detector alarm circuit.


4.1 TESTING

The smoke detector alarm has been tested with the 6V DC battery and it works properly. 

Its mode of operation is based on the principle that when smoke particles passes through the Light

Dependent Resistor(LDR), it detects the presence of smoke and in turns sends a signal to the buzzer

which in turns gives out an alarm.


C:\Users\BADMUS\AppData\Local\Microsoft\Windows\INetCache\Content.Word\IMG_20150604_142349.jpg



Plate 1.1 The smoke detector alarm circuit under testing.


C:\Users\BADMUS\AppData\Local\Microsoft\Windows\INetCache\Content.Word\IMG_20150604_142213.jpg

Plate 1.2 The charging circuit during testing.


4.3.RESULT
The testing carried out on the two circuits  tested positive and this shows that the smoke detector alarm is good for use and ready for use as well.

CHAPTER 5

5.0.CONCLUSIONIt is therefore concluded that the smoke detector alarm device is good for use in residential

departments  and it guarantees the safety of individuals depending on their response to the alarm.

5.1  RECOMMENDATION

The Smoke detector alarm is recommended for residential uses.




Comments