LIQUEFIED PETROLEUM GASLEAKAGE DETECTION SYSTEM

DECP ZG 511: Mechatronics

Submitted in partial fulfillment of M.Tech Design Engg. Degree Programme

by

ID No. Name of Student Name of Organization

2015HC30023 Sayali Chaudhari Cognizant Technology Solutions, Pune

2015HC30025 Chetan Nimje Eaton Technologies Pvt. Ltd, Pune

2015HC30010 Abhijeet Rathi Eaton Technologies Pvt. Ltd, Pune

2015HC30004 Vivek Karkade Eaton Technologies Pvt. Ltd, Pune

2015HC30037 Prabhat Tiwari Thermax Ltd, Pune

2015HC30031 Mayur Khapekar MAHLE Behr India Pvt. Ltd, Pune

Under the Supervision ofMr. Anand Mahurkar,

PartnerKrishna and Saurastri Associates, Pune

BIRLA INSTITUTE OF TECHNOLOGY & SCIENCECluster Programme, Yashada Pune

June 2016

1

CERTIFICATE

This is to certify that the project entitled “LIQUEFIED PETROLEUM GAS LEAKAGE

DETECTION SYSTEM” and submitted by following students for the partial fulfillment of the

requirements of M.Tech Design Engineering degree of BITS Cluster Programme, Yashada, Pune

Embodies the bonafide work done by her under my supervision.

ID No. Name of Student Name Of Organization Sign

2015HC30023 Sayali Chaudhari Cognizant Technology Solutions, Pune

2015HC30025 Chetan Nimje Eaton Technologies Pvt. Ltd, Pune

2015HC30004 Abhijeet Rathi Eaton Technologies Pvt. Ltd, Pune

2015HC30010 Vivek Karkade Eaton Technologies Pvt. Ltd, Pune

2015HC30037 Prabhat Tiwari Thermax Ltd, Pune

2015HC30031 Mayur Khapekar MAHLE Behr India Pvt. Ltd, Pune

______________________ Signature of the Supervisor

(Anand Mahurkar)

Place : ____________________

Date : ____________________

ABSTRACT2

Home Fires have taken a growing toll in lives and property in recent years. Liquefied

Petroleum Gas (LPG) is highly inflammable and can burn even at some distance from the source

of leakage. Most fire accidents are caused because of poor-quality rubber tube or when the

regulator is not turned off. The supply of gas from the regulator to the burner is on because of

malfunctioning of regulator. By accident, if the stove knob is turned on results in the gas leaks.

The Liquefied Petroleum Gas (LPG) Kit is many times installed inside the car as an alternate

fuel, creates possibilities of accidents if leakage occurs. These type of appliance or kits are not

always under the supervision of operating personnel, since it is automatic in operation and

therefore, the hazards encountered in the use of such an appliance creates the possibility during

standby or the period in which it is not in operation, a gas leak may occur thereby resulting in a

large accumulation of combustible gas which can produce an explosion if the detection is not

quickly noticed.

The purpose of the present project is, to provide a novel means for safely detecting any

malfunction of a pressurized gas system in order to prevent accumulation of combustible gases so

that damage or explosion is prevented. The system should be able to provide monitoring system

which is economical to manufacture and which may be readily available. The mechatronic

system developed can be used for domestic purpose like home, schools, colleges, and hospitals.

The leakage detection unit is incorporated with the alarm, to give sound signal to alert the

user about the Liquefied Petroleum Gas (LPG) concentration. The MQ2 sensor has excellent

sensitivity combined with a quick response time. Also sensor can also sense other flammable

gases like isobutene, propane, Liquefied Natural Gas (LNG) and alcohol.

ACKNOWLEDGMENT

3

I would like to express our sincere gratitude to the people who helped to bring this project to

success. First, I would like to thank Birla Institute of Technologies for providing me the

opportunity of taking part in Master of Design Engineering program. I would also like to

thank Professor Anand Mahurkar for his suggestions and encouragement, helped me in my

project especially in writing this report. His valuable suggestions will be very helpful for us

in future.

I would also like to extend my gratitude to Mr. Nilesh Kadam and Mr. Arpit Agrawal from

Eaton Technologies Pvt. Ltd. for their valuable inputs during Liquefied Petroleum gas (LPG)

leakage detection system circuit building.

A special thanks goes to my team mates, who helped me in various phases of project.

Without their contribution this project would not have been completed.

4

Sayali ChaudhariChetan NimjeAbhijeet RathiVivek KarkadePrabhat TiwariMayur Khapekar

TABLE OF CONTENTS

5

TOPICPAGE NO.

1. Introduction 81.1. Introduction 81.2. Need of LPG Leakage Detection System 91.3. Lower Explosive Limit 10

2. Liquefied Petroleum Gas and Literature Survey 112.1 Liquefied Petroleum Gas 11

2.1.1 Background 112.1.2 Characteristics 11

2.2 Literature Survey 123. Design And Development Of Mechatronic System 14

3.1 The need 143.1.1 Existing process of LPG detection 14

3.2 Preparation of Specification 143.3 Generation of possible solutions 15

3.3.1 Solution 1 153.3.2 Solution 2 153.3.3 Solution 3 16

3.4 Selection of possible solution 173.5 Production of detail design 173.6 Flow Diagram 173.7 Algorithm 18

4. Electrical Circuit And Components Information 194.1 Electrical Circuit 194.2 Components Information 20

4.2.1 Battery 204.2.2 7805 Voltage Regulator IC 214.2.3 Transistor 214.2.4 Resistors 214.2.5 Buzzer 224.2.6 MQ2 Gas Sensor 224.2.7 Working 22

4.3 Price list for Components 25 5 Testing Of Liquefied Petroleum Gas (LPG) Leakage Detection System 26

5.1 Experiment 1 265.1.1 Test setup 265.1.2 Assumptions 275.1.3 Observations 27

5.2 Experiment 2 27

6

5.2.1 Test setup 275.2.2 Assumptions 285.2.3 Observations 28

5.3 Conclusions 286 Conclusion & Future Scope 29

6.1 Conclusion 29 6.2 Future Scope 29

7 References 30

LIST OF FIGURSTOPIC PAGE NO.

Fig. 3.1 Schematic for Installation of LPG Leakage Detection System 16Fig. 3.2 Algorithm 18Fig. 4.1 General Circuit Diagram 19

7

Fig. 4.2 Actual Circuit Diagram 2Fig. 4.3 9V DC Battery 20Fig. 4.4 7805 voltage regulator 21Fig. 4.5 NPN Transistor 21Fig. 4.6 1K Ω &10k Ω resistors 21Fig. 4.7 Buzzer 22Fig. 4.8 MQ2 Sensor 22Fig. 4.9 MQ2 Sensor internal circuit 22Fig. 4.10 Structure and Configuration, basic and measuring circuit 23Fig. 4.11 Sensitivity Characteristics Curve 24Fig. 4.12 Dependency of MQ2 sensor on temperature and humidity 24Fig. 5.1 Test setup for Experiment 1 26Fig. 5.2 Test setup for Experiment 2 27

LIST OF TABLESTOPIC PAGE NO.

Table 1.1 Type of hazardous gases & their risks 9

Table 1.2 Typical threshold value of Lower Explosive Limit for flammable gases

10

Table 3.1 Flow Diagram for LPG leakage detector system 17Table 4.1 Voltage Rating of pins for 7805 Voltage regulator 21Table 4.2 Specifications 23Table 4.3 Price list for Components 25Table 5.1 Observation table for Experiment 1 27Table 5.2 Observation table for Experiment 2 28

LIST OF ABBRIVATIONSLPG Liquefied Petroleum GasCNG Compressed Natural GasLNG Liquefied Natural GasLEL Lower Explosive LimitSMS Short Message ServiceGSM Global System for MobileGPRS General Packet Radio Services

CHAPTER 1

INTRODUCTION

8

1.1 Introduction:Liquefied Petroleum Gas (LPG) leaks in gaseous or liquid form. If the liquid leaks it will

quickly evaporate and form a relatively large cloud of gas which will drop to the ground, as it is

heavier than air. LPG vapors can run for long distances along the ground and can collect in drains

or basements. LPG cylinders can explode if involved in a fire. The health impact of LPG is that,

it can cause cold burns to the skin and also can act as an asphyxiate at high concentrations. The

hydrocarbons and other chemicals present in the LPG causes negative effects on health such as

very long, sleep irritated respiratory tract, nose and eyes.

The objective of this project is to detect any leakage of Liquefied Petroleum Gas (LPG)/

Compressed Natural Gas (CNG) based cars, in home appliances, hospitals and hotels. It will

detect the leakage and will give sound signals to alert the people around. Gas sensors are now

being used in a wide range of applications in the fields like safety, health, instrumentation etc.

Common examples are domestic/commercial alarms for explosive or toxic gases, or in

automotive application as gas leakage detectors for LPG powered cars and exhausts quality

monitor for any fuel powered truck/car. Such sensors, nowadays, are found also in applications

involving air quality control systems and pollution monitoring.

Today’s sensors, while featuring a high sensitivity to a wide gases variety, are very

compact in size and have significantly reduced their power consumption to better adapt to

portable solutions. Still building a system with a gas sensor is not as easy as it could appear.

Despite the sensor could be treated, basically, as a variable resistor (which value depends on gas

concentration in air) the practical implementation in a project should be done considering some

design rules, especially if the final circuit is a device to be used in a field where reliability is

strongly required (e.g. safety). As an example the internal elements of a sensor (heater and gas

sensitive resistors) have to be constantly kept under control to avoid failures leading to a wrong

alarm indication; furthermore, if the application needs to achieve a good measurement accuracy,

factors like environment temperature, sensor life etc. have to be taken into account.

1.2 Need of LPG Leakage Detection System:

Gas leakage leads to various accidents resulting into both financial loss as well as human

injuries. In human’s daily life, environment gives the most significant impact to their health

issues. The risk of firing, explosion, suffocation all are based on LPG’s physical properties such 9

flammability, toxicity etc. The number of deaths due to the explosion of gas cylinders has been

increasing in recent years.

The reason for such explosion is due to substandard cylinders, old valves, worn out

regulators and lack of awareness using gas cylinders add to the risks. Inspections by oil

companies found that many LPG consumers are unaware of safety checks of gas cylinders.

Another reason is illegal filling of gas cylinder also causes accidents. There is a need for a system

to detect and also prevent leakage of LPG.

1.3 Lower Explosive Limit (LEL):

This only applies to low concentrations of combustibles gases, and it stands for Lower

Explosive Limit. It is the volume composition of a flammable gas in air. Below this limit no

10

Table 1.1 Type of hazardous gases & their risks

explosive atmosphere will be formed. Concentrations levels for gas detection purposes are

expressed in% of LEL. In other words it is a volume ratio of the gas relative to the LEL.

GAS LEL GAS LELAmmonia 15% Carbon Monoxide 12.5%

Butane 1.9% Isobutane 1.8%LPG 1.9% Hydrogen 4%

Methane 5% Gasoline 1.4%Toluene 1.1% Propane 2.1%

CHAPTER 2

LIQUEFIED PETROLEUM GAS (LPG)AND

11

Table 1.2 Typical threshold value of Lower Explosive Limit for flammable gases foflammable gases

LITERATURE SURVEY

2.1 Liquefied Petroleum Gas

2.1.1 Background:The LPG is finding wide range in homes, industries and in automobiles as fuels. In the

year 1910 LPG, first produced by Dr.Walter Snelling the U.S Bureau of mines investigated

gasoline to see why it evaporated so fast and discovered that the evaporating gases were propane,

butane and other light hydrocarbons. Both LPG and natural gas are environmental friendly they

easily be detected, these gases are normally stored in pressurized Steel cylinders in liquid form

and vaporize at normal temperatures. With comparison of air, LPG is heavier therefore it flows

along the floor and also settles in low points which make it difficult to disperse. LPG is a mixture

of commercial butane and commercial propane having both saturated and unsaturated

hydrocarbons. LPG marketed in India shall be governed by Indian Standard Code IS-4576 and

the test methods by IS-1448.

2.1.2 Characteristics:Kokula Krishna, Keerthivasan and Bhanu have mentioned charestaristics of LPG in

“Proceedings of the International Conference on Systems Science, Control, Communication,

Engineering and Technology 2015: ICSSCCET 2015” as follows: (a) Vapor pressure: The pressure inside a LPG storage vessel/ cylinder will be equal to the vapor

pressure corresponding to the temperature of LPG in the storage vessel. The vapor pressure is

dependent on temperature as well as on the ratio of mixture of hydrocarbons;

(b) Flammability: LPG has an explosive range of 1.8% to 9.5% volume of gas in air. This is

considerably narrower than other common gaseous fuels;

(c) Combustion: The combustion reaction of LPG increases the volume of products in addition to

the generation of heat. LPG requires up to 50 times its own volume of air for complete

combustion;

(d) Odor: LPG has only a very faint smell, and consequently, it is necessary to add some

odorant, so that any escaping gas can vapor phase, but can, however, suffocate when in large

concentrations due to the fact that it displaces oxygen.;

(e) Toxicity: LPG even though slightly toxic, is not poisonous in can pose a serious effect if they

leak.

12

2.2 LITERATURE SURVEY:Various researches have been done for Liquefied Petroleum Gas (LPG) Detector system.

“IOSR Journal of Electronics and Communication Engineering (IOSR-JECE)” by T.Soundarya,

J.V. Anchitaalagammai and two other authors have explained about “C-Leakage: Cylinder LPG

Gas Leakage Detection for Home Safety”. The paper talks about the microcontroller based LPG

leakage detection system. The purpose of this paper was to develop a system using Tmega328 p

microcontroller along with MQ6 sensor. The paper also give information on how weight

measurement system to detect the weight of the LPG cylinder and alert the users near to the refill

time of the cylinder. Project incorporated a GSM based circuit, through which the message can be

transferred to the user.

“LPG Leakage Monitoring and Multilevel Alerting System” is explained in

INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH

TECHNOLOGY by Selvapriya C, Sathya Prabha S. The invention uses LPG gas sensor for

sensing the leakage and produce the result in audio and visual formats also alerts human via Short

Message Service (SMS). This paper provides design approach on both software and hardware.

The purpose of this paper was to develop a system using MQ-5 Gas Sensor and Arduino UNO

board, GPRS Shield, Alarm unit, LED and Exhaust fan that fit into a small place. This papers

talks about usage of microcontroller system to send an active signal to other externally connected

devices.

“Automatic LPG Booking, Leakage Detection and Real Time Gas Measurement

Monitoring System” is developed by B. D. Jolhe, P. A. Potdukhe. International Journal of

Engineering Research & Technology (IJERT) Vol. 2 Issue 4 explains about the system. The

paper sheds light on the unique idea of automatic LPG booking and leakage detection. The

developed system was based on microcontroller (ATMega16A), gas sensor, weight sensor (Load

CellL6D), GSM module (SIMCOM 300), and 16 x 2 display(s). The LPG leakage is detected

through the sensor and information is sent to the user by Short Message Service (SMS) and

simultaneously alerts the customer using a GSM module, while activating the alarm and exhaust

fan. The additional advantage of the system is that it continuously monitors the level of the LPG

present in the cylinder using weight sensor and automatically books the cylinder using a GSM

module.

V.Ramya , B. Palaniappan have developed “Embedded system for Hazardous Gas

detection and Alerting system”. The main objective is to design microcontroller based toxic gas 13

detecting and alerting system. The developed system had hazardous gases like LPG and propane

sensed and displayed each and every second on the LCD display. The system was capable, if

these gases exceed the normal level then an alarm was generated immediately and also an alert

message (SMS) sent to the authorized person through the GSM. The paper talked about

advantage of the automated detection and alerting system over the manual method since it offered

quick response time and accurate detection of an emergency and in turn leading faster and

efficient handling of the critical situation.

“Automated unified system for LPG using microcontroller and GSM module- A Review”

is the paper published by B. B. Didpaye , Prof. S. K. Nanda. The paper talks about a cost-

effective, automated unified system for Liquefied Petroleum Gas (LPG) booking, leakage

detection, real time gas monitoring system and automatic controlling of LPG regulator. The aim

of this paper is to monitor for LPG leakage to avoid fire accidents providing house safety feature

where security has been an important issue. The paper gives information on the system that

detects the leakage of the LPG using gas sensor MQ6 and alerts the consumer about the gas

leakage by sending SMS using GSM module and simultaneously activating the alarm and exhaust

fan. The system built based on the paper additionally provides the automatically controlling of

LPG regulator. To avoid the blast this system will disconnect the main power supply using relay.

The additional advantage of the system is that it continuously monitors the level of the LPG

present in the cylinder using weight sensor and automatically books the cylinder using a GSM

module.

CHAPTER 3

DESIGN AND DEVELOPMENT OFMECHATRONIC SYSTEM

14

3.1 The need:

The need for development of present mechatronic system is to detect the leakage of

Liquefied Petroleum Gas (LPG). The alert should be sent to user about the possible leakage of the

LPG gas, so as to avert the risk of explosion and other health hazards.

3.1.1 Existing process of LPG detection:

The LPG cylinders are very widely used for domestic purposes like cooking, water

heating appliances, room heaters. With the advent of government policies of promoting more

usage of LPG in household usage and LNG/CNG as fuel for cars, since it causes very less

pollution and is highly environment friendly. This has resulted more interaction and taming of

flammable gases like LPG, CNG, and LNG by the small scale industries and domestic

consumers. Since these gases are being handled in pressurized containers and connected to user

end through valves, sometimes the malfunctioning of these valves, regulator, pipes connecting

cylinder to regulator and stove are caused due to factors such as handling of cylinder, household

environmental conditions, and presence of rodents, which may tear the connecting rubber pipe.

Therefore the leakage of gas may happen any at given conditions. Normally in Indian

household usage of LPG, we hardly find the utilization of gas leakage detection system.

Generally if the LPG gas gets leaked in any domestic environment it is detected only if any

person is standing in the vicinity. If this leakage goes unnoticed it may call up for any

catastrophic events.

3.2 Preparation of specification:

As we discussed, it becomes utmost important to have a system which can detect the

presence of any leakage caused from the cylinders containing LPG, CNG, or any other

inflammable gas. So whilst searching out for the solution, we must take care that, the LPG

leakage detection kit should be compact, battery powered, and should be easily placed near the

cylinder. Moreover to that it must be simple to operate and understand the functionality by the

end user. The sensor chosen must be able to detect all type of flammable gases. In addition if it is

able to detect some toxic gas then it will definitely improve the functionality of the leakage

detecting package.

3.3 Generation of possible solution:

15

3.3.1 Solution 1:

Various solutions can be generated to develop LPG leakage detection system. One

solution could be turn off the regulator knob to cut off the LPG flow. Making installation of

multi-function LPG regulator mandatory in every household could be the solution to gas

leakages which pose threat to life and property. The proposed device has safety features which

are useful for domestic Liquefied Petroleum Gas (LPG) cylinders. It has excess flow check valve,

built-in leak detector, child lock button and a pressure gauge. So when there is a gas leakage or

excess gas flow, the sensor detects the fault and shuts the valve automatically preventing any

further gas leakage. Besides this the sensor maintains a constant gas flow to the burner in normal

conditions. In last five years, many instances of gas leakages have been reported because of

improper handling, customer negligence, and leakages from the rubber tube, usage of sub-

standard equipment and exposure to intense heat. The three levels showing categorise into GAS,

LOW and REFILL. The GAS level indicates that there is plenty of gas in the cylinder, LOW level

indicates early warning of low gas in cylinder and REFILL indicates 10-15 per cent gas left in the

cylinder which indicates that it is time to book for the refill.

In between the cooking if the level of gas reaches refill zone, the LED display will

automatically alert the user by blinking red LED with audible alarm. Moreover the devise will

support gas output for maximum four burners. If more than this capacity is connected, the safety

feature automatically activates and shuts down the gas output. The 100 per cent excess flow shut-

off feature is designed to completely shut off flow of LPG in case high flow of LPG occurs due to

regulator failure, hose getting cut, burnt or ripped off. Also the built-in child lock feature will

restrict the knob movement towards ON position.

3.3.2 Solution 2:

Mechatronic system, developed in such a way that will give the wireless signal for LPG

leakage detection to the user. This system will give real time detection of potential risk; collect

the data of leak accident and reports to the proprietor. This system will use Wireless Gas Sensing

Network Technology for detecting the seepage of LPG. Gas detector which will detect the

presence of inflammable gases within an area can be used to develop mechatronic system. The

equipment will be used to detect gas leak and will transfer the information to the interfacing

control system. The hazardous gasses like Liquefied Petroleum Gas and Propane will be sensed

and displayed each and every second in Liquid Crystal Display. If these gases exceed normal

level then alarm will be given immediately. LED indicators will also be used to visualize the 16

status of system. In this system MQ-6 gas sensor employed to sense poisonous gas and it has high

sensitivity to LPG. The alert message will be received by the proprietor of an organization

through GSM Technology. This structure submits instant response time and accurate detection.

3.3.3 Solution 3:

Mechatronic system, which will give the sound signal to the people around about the LPG

leakage. This system focuses onto make anyone standing near the leaking LPG cylinder about the

possible danger by giving the buzzer sound. The system will be developed using MQ2 sensor and

5V buzzer. The developed system focuses on middle class economy as its target audience, who

will prefer a low cost LPG leakage detection system.

3.4 Selection of possible solution:

Considering the possible area of usage if being the domestic household environment, a

mechatronic system, which will give sound buzz for LPG leakage, should suffice the cause.

Also this system will be using relatively simple and cheaper components like sound buzzer. The

production cost and hence the selling price of the product will be quite less.

17

Buzzer

Switch

Front View

Back View

Provision for

Battery

(Fig. 3.1) Schematic for Installation of LPG Leakage Detection System

In the later part of this report we will discuss about the market cost of the solution suggested.

3.5 Production of detailed design:

a) Identification of input: LPG.

b) Identification of sensor: MQ2 sensor, to sense the leakage.

c) Identification of controlling elements:

Minimum 200 ppm of leaked LPG. Sensitivity of sensor

d) Identification of actuator:

Buzzer: to give sound signal about the leakage.

e) Identification of output:

Leakage signal, to make the people around aware about LPG leakage.

3.6 Flow Diagram:

The more than 200 ppm of leaked LPG will come in contact with the heater coil of the MQ2

sensor. This will cause the oxidation of the LPG. The following chemical reaction will take place.

C3H8 + 5O2 3CO2+ 4H2O

18

Table 3.1 Flow Diagram for LPG leakage detector system

Input Sensor Controller Actuator Output

Leaked LPG MQ2

Minimum ppm of leaked LPG.

Buzzer Leakage signal

Sensitivity of sensor

The oxidation at the heated terminal of MQ2 sensor will result in the drop of internal resistance.

Thus allowing the current to pass through it and the circuit will get complete. Buzzer will start

giving the sound output, alerting the user.

3.7Algorithm:

Start

Check if leaked LPG is present in vicinity.

If yes- give buzzer signals

If no- no buzzing signals

CHAPTER 4

ELECTRICAL CIRCUITAND COMPONENTS INFORMATION

19

(Fig. 3.2) Algorithm

Three possible solutions are generated for LPG leakage detection mechatronic system.

Out of three “solution 3” have been selected for design and development. The system described

in “solution 3” will be relatively less complicated and economical. The developed system will be

typically used for domestic purpose. The circuit design for LPG leakage detection system is

explained below:

4.1 Design Electrical Circuit:The circuit for LPG leakage detection system simple and comprises few components.

Fig. (4.1) shows typical circuit for LPG leakage detection system developed using components

mentioned below:

20

(Fig. 4.1) General Circuit Diagram

a. Battery

b. 7805 IC voltage regulator

c. Transistor

d. Resistors

e. Buzzer

f. MQ2 Sensor and

g. Switch.

The voltage converter circuit device utilizes the 7805 IC to drop the voltage from 9V to 5V.

This voltage is provided to buzzer as well as MQ2 sensor. The current is feed into the buzzer via

sensor. Sensitive material of MQ-2 gas sensor is SnO2, which has lower conductivity in clean air.

When the target combustible gas exist, the sensor’s conductivity is higher along with the gas

concentration rising. The change of conductivity corresponds to the output signal of gas

concentration. This drives the alarm circuit.

4.2Components Information:

4.2.1 Battery:

21

(Fig. 4.2) Actual Circuit Diagram

(Fig. 4.3) 9V DC Battery

Battery

Switch

MQ2 Sensor Buzzer

7805 IC Voltage Regulator

4.2.2 7805 Voltage Regulator IC:

7805 is a voltage regulator integrated circuit. It is a member of 78xx series of fixed linear voltage

regulator ICs. The voltage source in a circuit may have fluctuations and would give the fixed

voltage output. The voltage regulator IC maintains the output voltage at a constant value. The xx

in 78xx indicates the fixed output voltage it is designed to provide. 7805 provides +5V regulated

power supply. Capacitors of suitable values can be connected at input and output pins depending

upon the respective voltage levels.

4.2.3 Transistor:

A transistor is a semiconductor device used to amplify and switch electronic signals and

electrical power. It is composed of semiconductor material with at least three terminals for

connection to an external circuit.

4.2.4 Resistors:

A resistor is a passive two-terminal electrical component that implements electrical resistance as

a circuit element. Resistors may be used to reduce current flow, and, at the same time, may act to

lower voltage levels within circuits.

22

(Fig. 4.4) 7805 voltage regulator Table 4.1 Voltage Rating of pins for 7805 Voltage regulator

(Fig. 4.5) NPN Transistor (Fig. 4.6) 1K Ω &10k Ω resistors

Pin No Function Name

1 Input voltage (5V-18V) Input

2 Ground (0V) Ground

3 Regulated output; 5V (4.8V-5.2V) Output

4.2.5 Buzzer:

A buzzer or beeper is an audio signaling device, which may be mechanical, electromechanical,

or piezoelectric.

4.2.6 MQ2 gas sensor:

4.2.7 Working:

When the target combustible gas exist, the sensor’s conductivity gets higher along with the gas

concentration rising. By converting the change of conductivity to correspond output buzzer signal

about gas concentration. MQ-2 gas sensor has high sensitivity to LPG, Propane and Hydrogen,

also could be used to Methane and other combustible steam. It comes with low cost and suitable

for different application. In order to make the sensor with better performance, suitable RL value

is needed: Power of Sensitivity body (Ps):

Ps=Vc2×Rs/ (Rs + RL) ^2

23

(Fig. 4.7) Buzzer

(Fig. 4.8) MQ2 Sensor (Fig. 4.9) MQ2 Sensor internal circuit

24

Table 4.2 Specifications

(Fig. 4.10) Structure and Configuration, basic and measuring circuit

RO: Sensor resistance at 1000 ppm of H2 in air at 33% RH and 20o.

RS : Sensor resistance at 1000 ppm of H2 in different temperatures and humidity.

25

(Fig. 4.11) Sensitivity Characteristics Curve

(Fig. 4.12) Dependency of MQ2 sensor on temperature and humidity

4.3 Price list for Components:

The components used for LPG Leakage Detection System are readily available in market and

economical.

Sr

No.Component QTY

Price per

item (in )₹Total price of

components

1 Battery 1 15/- 15/-

2 MQ2 Sensor 1 160/- 160/-

3 7805 Voltage Regulator IC 1 30/- 30/-

4 Buzzer 1 8/- 8/-

5 Transistor 1 1/- 1/-

6 Resistors 3 10/- 30/-

7 Switch 1 30/- 30/-

8 Jumper wires (connecting wires) 1 10/- 10/-

9 PCB 1 60/- 60/-

Total 344/-

26

Table 4.3 Price list for Components

CHAPTER 5

TESTING OF LIQUEFIED PETROLEUM GAS (LPG) LEAKAGE DETECTION SYSTEM

The working of LPG leakage detection system depends on MQ2 sensor. The purpose of

sensor is to detect any inflammable gas near its vicinity. The buzzer will work only when sensor

does its job properly. The performance of LPG leakage detection system is depending on how

well sensor performs. This makes MQ2 sensor crucial component of the present mechatronic

system. Hence, the performance of sensor should be tested under various conditions to make sure

sensor will perform under different working conditions.

LPG leakage detection system is designed to be used for domestic purpose. The system

should operate under all temperature conditions throughout the day. The sensor will operate when

inflammable gases will come in vicinity. Hence, the distance between LPG leakage detection

system and leakage site plays important role in system operation.

An experiment is carried out to test the performance of sensor at various temperature

conditions throughout day. Another experiment is carried out to test performance of sensor with

respect to its distance from leakage site.

5.1 Experiment 1:The experiment is carried out to test performance of sensor with respect to different temperature

conditions.

5.1.1 Test setup:

27

Please put an image

(Fig. 5.1) Test setup for Experiment 1

5.1.2 Assumptions:

The experiment is carried out on a day when; Min. Temperature: 24° C

Max. Temperature: 30 ° C

Humidity: 40%

LPG leakage detection system is fitted near LPG cylinder. The knob of LPG cylinder is switched

on every hour and time taken by buzzer to start giving output is recorded.

5.1.3 Observations:

Sr no. Hour TemperatureIn ° C

Time taken by buzzer to give output in sec.

1 9.00 am 26 32 10.00 am 28 43 11.00 am 29 44 12.00 pm 31 45 13.00 pm 31 36 14.00 pm 31 37 15.00 pm 30 48 16.00 pm 30 39 17.00 pm 29 410 18.00 pm 29 411 19.00 pm 27 312 20.00 pm 25 313 21.00 pm 25 4

5.2 Experiment 2:

The experiment is carried out to test performance of sensor with respect to distance from

installation site.

5.2.1 Test setup:

28

Please put an image

Table 5.1 Observation table for Experiment 1

(Fig. 5.2) Test setup for Experiment 2

5.2.2 Assumptions:

The sensor will work when inflammable gas comes near to it. Based on this information initial

distance is taken as 2 ft.

LPG leakage detection system is placed near LPG cylinder at 2 ft. distance and checked whether

buzzer gives output. Readings have been taken in the form of Yes/ No for buzzer output at

various distances reducing form 2 Ft.

5.2.3 Observations:

Sr no. Distance form LPG cylinder in Ft.

Buzzer outputYes/ No

1 2 No2 1.75 No3 1.5 No4 1.25 No5 1.00 Yes6 0.75 Yes7 0.5 Yes8 0.25 Yes

9 Touching to the cylinder Yes

5.3 Conclusions:Based on experiment carried out to test the performance of MQ2 sensor, it is found that

performance of sensor is irrespective of temperature. The conclusion if second experiment is,

LPG leakage detection system should be as near to leakage site as possible. The maximum

distance between leakage detection system and leakage site should be 1 ft.

29

Table 5.2 Observation table for Experiment 2

CHAPTER 6

CONCLUSION & FUTURE SCOPE

6.1 Conclusion:The purpose of preset mechatronic system is to provide safe, reliable, simple and cost

effective LPG leakage detection system. The circuit designed for present mechatronic system is

simple in comparison with other LPG leakage detection system available in market. The

components which are used to build the circuit are cost effective and readily available in market.

The working of the system is particularly depends on performance of the sensor. Working of the

MQ2 sensor is this leakage detection system is irrespective of ambient temperature where the

system is installed. The guidelines should be provided while installing the system that, maximum

distance between system and leakage site should be 1 ft. The system is cost effective and can be

used in domestic applications like kitchens, hotels, cafeterias, hospitals and train pantries.

6.2 Future Scope:As no system is perfect, neither is this one. So it leaves us with the further scope of

improvement. Battery used in the system is of 9V DC supply which may not suffice for more

than 15 days, in further improvement, we can use a bigger, rechargeable one, which can sustain

the gas detection module for at least a month, with warning signal whenever battery runs out. In

further modification, in addition to only leakage gas detection, the weight measurement system

can also be incorporated, thus giving the user intimation about the refill time of cylinder. The

project has a good viability to be launched in commercial market, small scale industries having

multiple cylinders stored. With further improvement in design and making system more handy

and cost effective for the end user.

REFERENCES30

Dissertation and Theses:1. T.Soundarya, J.V. Anchitaalagammai , G. Deepa Priya , S.S. Karthick kumar, C-Leakage:

Cylinder LPG Gas Leakage Detection for Home Safety, IOSR Journal of Electronics and

Communication Engineering (IOSR-JECE), e-ISSN: 2278-2834,p- ISSN: 2278-

8735.Volume 9, Issue 1, Ver. VI (Feb. 2014), PP 53-58 www.iosrjournals.org

2. Selvapriya C, Sathya Prabha S , Abdulrahim M , Aarthi K C, LPG Leakage Monitoring

and Multilevel Alerting System, INTERNATIONAL JOURNAL OF ENGINEERING

SCIENCES & RESEARCH TECHNOLOGY, November, 2013

3. B. D. Jolhe, P. A. Potdukhe, N. S. Gawai, Automatic LPG Booking, Leakage Detection

And Real Time Gas Measurement Monitoring System B. D. Jolhe, P. A. Potdukhe, N. S.

G , Jawaharlal Darda Institute of Engineering and Technology, International Journal of

Engineering Research & Technology (IJERT) Vol. 2 Issue 4, April - 2013 ISSN: 2278-

0181

4. V.Ramya , B. Palaniappan, Embedded system for Hazardous Gas detection and Alerting,

International Journal of Distributed and Parallel Systems (IJDPS) Vol.3, No.3, May 2012

5. B. B. Didpaye , Prof. S. K. Nanda, Automated unified system for LPG using

microcontroller and GSM module- A Review, International Journal of Advanced

Research in Computer and Communication Engineering Vol. 4, Issue 1, January 2015

Book Reference:6. Proceedings of the International Conference on Systems, Science, Control,

Communication, Engineering and Technology 2015: ICSSCCET 2015

Kokula Krishna Hari K, Keerthivasan M, D Bhanu, Page 22-23.

7. Tolley's Basic Science and Practice of Gas Service, By Frank Saxon, Page 21

Web References:8. http://www.thomasnet.com/articles/instruments-controls/How-Gas-Detectors-Work

9. https://en.wikipedia.org/wiki/Gas_detector#Household_safety

10. http://www.instructables.com/id/How-to-use-MQ2-Gas-Sensor-Arduino-Tutorial/

11. https://en.wikipedia.org/wiki/Gas_detector

31

1 Checklist of items for the Project ReportThis checklist is to be attached as the last page of the report.

This checklist is to be duly completed, verified and signed by the student.1. Is the final report properly bound? Yes / No2. Is the Cover page in proper format as given in Annexure? Yes / No3. Is the Title page (Inner cover page) in proper format? Yes / No4. (a) Is the Certificate from the Supervisor in proper format?

(b) Has it been signed by the Supervisor?Yes / NoYes / No

5. Is the Abstract included in the report properly written within one page? Have the technical keywords been specified properly?

Yes / No

Yes / No6. Is the title of your report appropriate? The title should be adequately

descriptive, precise and must reflect scope of the actual work done.

Yes / No

7. Have you included the List of abbreviations / Acronyms?Uncommon abbreviations / Acronyms should not be used in the title.

Yes / No

8. Does the Report contain a summary of the literature survey? Yes / No9. Does the Table of Contents include page numbers?

(i). Are the Pages numbered properly? (Ch. 1 should start on Page # 1)(ii). Are the Figures numbered properly? (Figure Numbers and Figure

Titles should be at the bottom of the figures)(iii). Are the Tables numbered properly? (Table Numbers and Table Titles

should be at the top of the tables)(iv). Are the Captions for the Figures and Tables proper?(v). Are the Appendices numbered properly? Are their titles appropriate

Yes / No

Yes / No

Yes / NoYes / NoYes / No

10. Is the conclusion of the Report based on discussion of the work? Yes / No11. Are References or Bibliography given at the end of the Report?

Have the References been cited properly inside the text of the Report?Is the citation of References in proper format?

Yes / No

Yes / No

Yes / No12. Is the report format and content according to the guidelines? The report

should not be a mere printout of a Power Point Presentation, or a user manual. Source code of software need not be included in the report.

Yes / No

Declaration by Student:I certify that I have properly verified all the items in this checklist and ensure that the report is in proper format as specified in the course handout.

________________________________ Place: ________________________ Signature of the Student

Date: _________________________ Name: ___________________________

ID No.: ___________________________

32