8051microcontroller based gas and fire alarm system+ppt

8/10/2019 8051MICROCONTROLLER BASED GAS AND FIRE ALARM SYSTEM+ppt

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8051M ICROCONTROLLER

BASED GAS AND FIRE ALARM

SYSTEM


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NEED FOR THE PROJECT :

Current technology is effective but not

inclusive.

Heat alarm systems are being used.

Needed in high rise buildings and hospitals.


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INTRODUCTION:

Safety during fire and gas leak emergencies.

Prevention using manumatic system.

Alert people belonging to high risk groups.


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Contd..

NFPA sponsored researches.

But, researches into the effectiveness of thealerting methods has been sparse.

Several methods published by UnderwritersLaboratory are used.


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Contd..

Development of stand alone alarm system.

This project:

1. Combines the concept of home automation

with alarm systems.

2. Uses the concept of tactile stimulation.

Why manual controlling?


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WATER

VALVE

EXHAUST

FANVIBRATOR

ELECTRIC

LOCKAPPLIANCES

MAINS

SUPPLY

JRELAY BOARD

GASSENSOR

SMOKE

SENSOR

MICRO

CONTROLLER

8051

LCD

MAX

232

GSM

MODEM

BUZZER

STEPPERMOTOR

GASVALVE

POWERSUPPLY

Fig.1 8051 based Gas and Fire Alarm System


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GSM

MOBILE

TRANSMITTER\RECEIVER :

Fig.2 GSM Mobile device


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SENSORS

Semiconductor sensors- made with a porous

assembly of Sno2

MQ2 sensor- detects smoke

MQ6 sensor- detects LPG


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FACTORS AFFECTING SENSORS

PERFORMANCE

THREE KEY FACTORS

Receptor function-selection of a foreignreceptor which enhances surface reactions or

adsorption of target gas Transducer function-oxide with high mobility

of conduction electrons and satisfactory

stability Utility factor-fabrication of a highly porous,

thin sensing body


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Basic measuring circuit

Input voltage= 5v DC

Two voltage inputs Vc and Vh

Resistance of sensor(Rs): Rs=(Vc/VRL-1)RL

Fig.3 Basic Test Loop


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Contd..

Fig.5 Model of inter-grain potential barrier

(in the presence of gases)


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Contd..

Sensing material- Sno2

Oxygen is adsorbed-donor electrons in the

crystal surface are transferred to the adsorbed

oxygen

Surface potential is formed

In the presence of deoxidizing gas electrical

resistance is reduced


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Rs = A[C] ^(- )

where: Rs = electrical resistance of the sensor

A = constant

[C] = gas concentration

= slope of Rs curve

Eqn.1 Scheme of reaction between CO and adsorbed oxygen

on SnO2.

MQ2


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MQ2

Fig.6 Relationship between resistance ratio of the sensor and

concentration


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MQ2

Fig.7 relationship between resistance ratio and

temperature/humidity


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MQ6

Fig.8 Relationship between resistance ratio of the sensor and

concentration


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MQ6

Fig.9 Relationship between resistance ratio and

temperature/humidity


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Fig. 10 Signal flow from sensor to Microcontroller

SensorsLM358D

Comparator

NOT GateMicro-

controller


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Microcontroller:-

P89V51RD2 is an 8051 microcontroller.

EEPROM.

SPI and enhanced UART.TTL- and CMOS-compatible logic levels.

Four 8-bit I/O ports.

ISP and IAP.

Flash and Data RAM memory.


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Block diagram:-

Fig.11 Architecture of P89V51RD2


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Fig. 12 Pin details of P89V51RD2 Microcontroller

LCD

Specific

PurposeSensors

Appliances


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Liquid Crystal Display(LCD):-

Programmable baud rate 9600bps or

19200bps.

Simple serial command

clear screen, linefeed, clear row, clear column etc

Two register-Data and Command register

Sending ASCII characters to the serial LCD

will result in text display on the LCD screen.

Fig.13 LCD display


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LCD interface to MC:-Pin No. Symbol Description

1 Vss

Ground Terminal, 0V

2 Vdd

Supply Terminal, +5V

3 VLCD

Power supply to control Contrast

4 RS

Register Select:

RS = 0-

Instrution Register

RS = 1-Data Register

5 R/W

Read/Write:

R/W = 0

Write

R/W = 1Read

6 EN

Enable

7-14 DB0-DB7

8-bit Data Bus

15-16 Backlight

Supply

In case of 15-pin module, pin-15 is the

supply voltage(+5) for the LED. In case

of 16-pin module, pin 15 is the ground

and pin 15 is the supply for the LED.

Fig.14 Ckt diagram of LCD


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Power Supply:-

Fig. 15 Ckt diagram of AC-DC Adapter


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The microcontroller and other devices get power supplyfrom ac to dc adapter through voltage regulator.

The adapter output voltage will be 12v dc non-regulated.

The 7805 voltage regulators are used to convert 12 V to

5 V dc.

Fig. 16 Power Supply Conversion unit

230v 12v 5v

Contd


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GSM

Founded in 1982

Most popular standard for mobile

telephone systems

International roaming

Second generation (2G)
http://en.wikipedia.org/wiki/File:GSMLogo.svg


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Ability to switch carriers and also

network operators

Tri-band operation

Tiny configuration

Implementation of short text message

(sms)


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GSM is a cellular network

Uses GMSK modulation

SIM

GSM-easily configured using ATcommands


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Some of the AT commands:

AT+CMGD=used to delete a message.

AT+CMGS=used to send a message.

AT+CMGR=used to read a message.


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APPLICATION

High-raise buildings

For high risk group people

For domestic purposes

In gas distribution units


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ADVANTAGES

Easy to design

Manually operated

8051 can be interfaced Appliances can be controlled using GSM

Multi-functioned

Home-automation can also be done Compatibility


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LIMITATIONS

GSM signal strength

The strategic placement of the system isnecessary


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SOFTWARE REQUIREMENTS :

Keil Micro vision.

LPC2000 Flash Utility.


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FUTURE ENHANCEMENTS

A microphone can be connected

The module can be connected to drivemore complex equipments

Development of remote warning handsets


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CONCLUSION

This project is a combination of

Home-Automation and Alarm

systems.

Committed to create innovativesolutions


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THANK YOU

8051microcontroller based gas and fire alarm system+ppt

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