ABSTRACT

Gas is supplied in pressurized steel cylinders. As this gas is heavier than air, when it leaks from the cylinder it flows along floor and tends to settle in low spots such as a basement to cause fire or suffocation if not dealt with. To handle gas leak situations, this project presents the design and construction of a Gas detection system. A gas detection system is an electronic device that detects leakage of liquefied petroleum gas and alerts the user through acoustic indication. The system consists of micro controller, drivers, regulated power supply, alarm circuit and an MQ-6 gas sensor. The MQ-6 gas sensor has a high sensitivity to propane, butane, dissoluteness, natural gas and can also be used to detect combustible gases, especially methane. The project is designed to detect LPG from concentration of 200 PPM (parts per million) to 10,000 PPM in an area, then the out pin of the sensor goes low to drive a micro controller which is programmed to produce a high frequency alarm. A buzzer is used to produce the high frequency audible alert signal while a 9v battery powers the system. This project can be used to detect gas leakages at home, in a car, storage tank environment or in a service station. It can be easily implemented to industrial level by upgrading its ranges. The implementation of the project is so important in every home, office and industries because there are many gases that can be harmful to organic life, such as humans or animals.

LIST OF FIGURES

Figure 1.8: Project Organizations Block Diagram- – – – 8
Figure 2.3: Ventilator Automatic Gas Detector [8] – – – 13
Figure 3.2 Block Diagram Design of the System– – – 23
Figure 3.3.1 Mq-6 Gas Sensor [9] – – – – – 25
Figure 3.5: Transistor Buffer– – – – – – 27
Figure 3.7: Dc Regulator [10]– – – – – – 28
Figure 3.8: Buzzer [11]- – – – – – – – 30
Figure 3.9: Light Emitting Diode [12]- – – – – 31
Figure 3.10: Four Types of Diodes [13]- – – – – 32
Figure 3.11: Electrolytic Capacitor [14]- – – – – 33
Figure 3.12: Fix Resistor [15]- – – – – – 35
Figure 3.13: A Toggle Switch [16]- – – – – – 36
Figure 3.14: Four Types of Transistor [17] – – – – 36
Figure 4.1: systematic Circuit diagram of the project – – – 40
Figure 4.1:1 Circuit diagram of the project- – – – – 41
Figure 4.2: PVC wire [18]- – – – – – – 42
Figure 5.4:1 The picture of the project- – – – – 48

TABLE OF CONTENTS

Title page — – – – – – – – – – i
Certification – – – – – – – – – – ii
Approval page – – – – – – – – – – iii
Dedication – – – – – – – – – – – iv
Acknowledgement – – – – – – – – – v
Abstract – – – – – – – – – – – vi
List of figure – – – – – – – – – – vii
Table of contents – – – – – – – – – – viii

CHAPTER ONE

Introduction
1.1 Background of Study- – – – – – – – 1
1.2Problem Statement– – – – – – – – 3
1.3 Aim and Objectives – – – – – – – – 5
1.4 Significant of the project – – – – – – – 6
1.5 Scope of Study – – – – – – – – – 6
1.5 Justification of the Project – – – – – – – 6
1.7 limitations – – – – – – – – – 7
1.8 project report organization – – – – – – – 8

CHAPTER TWO

Literature Review
2.1 History of Gas Detection system – – – – – – 10
2.2 History on Gas Detector Development- – – – – 11
2.3 How Gas Detectors Work- – – – – – – 12
2.4 Methods of Gas Detection- – – – – – – 13

CHAPTER THREE

3.1 Design Methodology – – – – – – – – 21
3.2 System Design Method – – – – – – – 23
3.3 System Analysis – – – – – – – – 24
3.4 Circuit working – – – – – – – – 26
3.5 microcontroller unit – – – – – – – – – 26
3.6 power supply unit — – – – – – – – 27
3.7 DC regulator – – – – – – – – – – 28
3.8 Other components used in the project – – – – – – 29
3.9 LED – – – – – – – – – – – 31
3.10 Diode – – – – – – – – – – – 31
3.11 Capacitor- – – – – – – – – – 32
3.12 Resistors – – – – – – – – – – 33
3.13 Switch- – – – – – – – – – – 35
3.4 Transistor – – – – – – – – – – 36

CHAPTER FOUR

System Implementation
4.1 Construction procedures – – – – – – – 38
4.2 Interconnection of components – – – – – – 41
4.3 Software implementation – – – – – – – – 42
4.4 Program hex file- – – – – – – – – 43
4.5 Project costing – – – – – – – – – 44

CHAPTER FIVE

System Testing and Packaging
5.1 System Test – – – – – – – – – 46
5.2 Test Plan and Test Data – – – – – – – 46
5.3 Components Test – – – – – – – – 47

5.4 Packaging – – – – – –