DESIGN AND CONSTRUCTION OF A MICRO CONTROLLER BASED AUTOMATIC FIRE EXTINGUISHING SYSTEM

0
5

DESIGN AND CONSTRUCTION OF A MICRO CONTROLLER BASED AUTOMATIC FIRE EXTINGUISHING SYSTEM

ABSTRACT

Despite many buildings have fire fighting systems installed in them; many people are still losing their lives and properties due to fire accidents. In this research, an automatic cost effective device for the detection and control of fire has been designed and constructed. The system has an additional feature of sending signal to a pump/sprinkler through a relay. It is made up of two sensors, microcontroller, buzzer and a controlled fire fighting equipment (pump/sprinkler). LM 35 IC has been used as temperature sensor while MQ-2 gas sensor has been used as smoke sensor. All sensors are connected to the microcontroller through an input/output port. The controlling software for the whole system was designed in C programming language. The popular high performance, low power 8-bit microcontroller from the AVR family microcontrollers was used. The system was finally tested by introducing fire parameters (smoke and temperature) close to the detectors. When the parameters go above the set level in the detectors, audio alarm, LED indicator and pump/sprinkler were activated. The measured temperature of the system was compared with the reference temperature. The result showed that there was a mean deviation of 1.550C between the measured values and reference values which served as the control.

CHAPTER ONE INTRODUCTION

  1. Background to the study

The need for early fire detection is paramount in protecting human life and property as fire disaster is a great threat to lives and propertiesFire is the rapid oxidation of a material in the exothermic chemical process of combustion, releasing heat, light, and smoke. It is understood

that every fire start with a smoke and heat. A key subject of interest to many researchers has thus been on fire fighting systems. More interest has been given on automation of these systems to allow fire fighting operation be less dependent on human support. Automated fire fighting system, which depends on temperature and smoke sensing devices, is used in many industrial and commercial applications. It is however true that in most cases sensible heat often occurs after great destruction has occurred and thus the use of smoke sensors need not be ignored at any point whatsoever. A number of fire detectors have been designed that can be installed within buildings. Among these types of sensors, the smoke sensor is widely used because of its early fire detection capability and its relatively low cost (Richard et al., 1998). However, although this sensor provides rapid response time, it has high false-alarm rates. In contrast, the temperature sensor provides more reliable responses but with slow response time. Fire detectors that use a single sensor may fail to activate when required or may cause false alarms. Therefore, a fire detecting system that uses a combination of smoke and temperature sensors will not only provide better smoke sensor compensation but also provide a more intelligent fire control system (Cheon et. al., 2009).

The need to safeguard lives and properties from fire disasters has led to the invention of an automatic fire control system using a smoke detector, a heat detector and an automatic sprinkler (Bukowski et. al., 1999). Automatic fire alarm system provides an immediate surveillance, monitoring and automatic alarm. It sends early alarm when the fire occurs and

helps to reduce the damage (Zhang and Wang, 2009). A smoke and heat detector is one of the numerous ways of detecting fire outbreak at an early stage, while a water sprinkler is the  most common way of extinguishing fire. An automatic fire control system is an electronic circuit designed to control a sprinkler which produces water or any extinguishing element, when it detects the presence of smoke and excessive heat (Bukowski et. al., 1999).

The automatic fire control system brings out efficient automatic fire detection and extinguishing system. The fire detection sensors will sense the occurrence of fire, by monitoring smoke and heat, which automatically generate a signal to interrupt the micro-controller which is connected to a buzzer and a pump. Suddenly after detecting the fire, the buzzer automatically sounds to indicate the presence of fire and starts the relay which runs a pump and pressurizes the extinguishing element to suppress the fire using water sprinkler. The role of the control unit in improving fire detection and control capability has already been recognized, with a system using control unit for decision making being one of two main versions of intelligent fire detection systems (Liu et. al., 2008).

DESIGN AND CONSTRUCTION OF A MICRO CONTROLLER BASED AUTOMATIC FIRE EXTINGUISHING SYSTEM

DESIGN AND CONSTRUCTION OF A MICRO CONTROLLER BASED AUTOMATIC FIRE EXTINGUISHING SYSTEM