12-11-2012, 01:15 PM
A project report On INTELLIGENT FIRE DETECTOR WITH AUTOMATIC WATER SRINKLE SYSTEM
NTELLIGENT FIRE DETECTOR.doc (Size: 660 KB / Downloads: 95)
ABSTRACT
Security is primary concern for every one. There are many ways to provide security at homes or in industries. The main aim of this project is to continuously monitor the house or industries and if any fire accidents occur, the system should immediately start the sprinkle. A fire sensor will be fixed in the house or in an industry. The status of this sensor will be continuously monitored by the op-amp. The operational amplifier is used as a comparator in this project. To one of the inputs of the op-amp, the output of fire detector is given and the reference voltage is given to the other input of the op-amp.
Since the output of op-amp is given to the relay and if the sensor value exceeds the reference voltage, the input at the relay changes and thus, the sprinkler will be started according to the input of the relay. The Purpose of a Fire Detection and Alarm System is to detect the Fire and its location at the earliest practicable moment and to give an Alarm Organization, triggering exhaust fan, extinguishing processes, etc. An Alarm System may be activated by automatic detection devices such as Smoke/Heat Detectors or by manual operation of manual call points.
Fire sprinklers can be automatic or open orifice. Automatic fire sprinklers operate at a predetermined temperature, utilizing a fusible element, a portion of which melts, or a frangible glass bulb containing liquid which breaks, allowing the plug in the orifice to be pushed out of the orifice by the water pressure in the fire sprinkler piping, resulting in water. This is often the function of the fire detection and alarm system. Several system types and options are available, depending on the specific characteristics of the protected space. Fire protection experts generally agree that automatic sprinklers represent one of the single, most significant aspects of a fire management program. A more advanced sprinkler system became possible as technology became more sophisticated. Sprinkler systems automatically detect and then control, suppress, or extinguish fires.
INTRODUCTION
Cultural property management is entrusted with the responsibility of protecting and preserving an institution's buildings, collections, operations and occupants. Constant attention is required to minimize adverse impact due to climate, pollution, theft, vandalism, insects, mold and fire. Because of the speed and totality of the destructive forces of fire, it constitutes one of the more serious threats. Vandalized or environmentally damaged structures can be repaired and stolen objects recovered. Items destroyed by fire, however, are gone forever. An uncontrolled fire can obliterate an entire room's contents within a few minutes and completely burn out a building in a couple hours. The first step toward halting a fire is to properly identify the incident, raise the occupant alarm, and then notify emergency response professionals. This is often the function of the fire detection and alarm system. Several system types and options are available, depending on the specific characteristics of the protected space. Fire protection experts generally agree that automatic sprinklers represent one of the single, most significant aspects of a fire management program. Properly designed, installed, and maintained, these systems can overcome deficiencies in risk management, building construction, and emergency response. They may also provide enhanced flexibility of building design and increase the overall level of fire safety.
HISTORY:
The first automatic sprinkler system was developed in the 1870s, a sprinkler system consisted of a perforated pipe, a valve, a person to open the valve, and an elevated barrel or tank filled with water. A more dependable system was created in response to increased fire loads and increased values of buildings and their contents. A more advanced sprinkler system became possible as technology became more sophisticated.
Water supplies can come from city water mains, dedicated storage tanks or ponds. Valves and alarm devices control and monitor the water’s flow. Distribution pipes send water to the sprinkler heads using a municipal water source to maintain and increase water pressure according to design criteria. Modern systems can detect a fire condition and discharge water quickly, before a fire grows to a fatal or catastrophic size, reducing fire deaths by nearly 100percent.Understanding your fire sprinkler system can be life saving. After reading this guide, you will be more knowledgeable about the water flow detectors, supervisory switches, pressure switches, explosion proof products, and alarm bells within a fire sprinkler system.
FIRE GROWTH AND BEHAVIOUR:
Before attempting to understand fire detection systems and automatic sprinklers, it is beneficial to possess a basic knowledge of fire development and behavior. With this information, the role and interaction of these supplemental fire safety systems in the protection process can then be better realized. Basically, a fire is a chemical reaction in which a carbon based material (fuel), mixes with oxygen (usually as a component of air), and is heated to a point where flammable vapors are produced. These vapors can then come in contact with something that is hot enough to cause vapor ignition, and a resulting fire. In simple terms, something that can burn touches something that is hot, and a fire is produced.
Successful fire suppression is dependent on extinguishing flames before, or immediately upon, flaming combustion. Otherwise, the resulting damage may be too severe to recover from. During the incipient period, a trained person with portable fire extinguishers may be an effective first line of defense. However, should an immediate response fail or the fire grow rapidly, extinguisher capabilities can be surpassed within the first minute. More powerful suppression methods, either fire department hoses or automatic systems, then become essential.
FIRE DETECTION AND ALARM SYSTEMS:
A key aspect of fire protection is to identify a developing fire emergency in a timely manner, and to alert the building's occupants and fire emergency organizations. This is the role of fire detection and alarm systems. Depending on the anticipated fire scenario, building and use type, number and type of occupants and criticality of contents and mission, these systems can provide several main functions. First they provide a means to identify a developing fire through either manual or automatic methods and second, they alert building occupants to a fire condition and the need to evacuate. Another common function is the transmission of an alarm notification signal to the fire department or other emergency response organization .This section will describe the basic aspects of fire detection and alarm systems. There are several options for a building's fire detection and alarm system. The ultimate system type, and selected components, will be dependent upon the building construction and value, its use or uses, the type of occupants, mandated standards, content value, and mission sensitivity. Contacting a fire engineer or other appropriate professional who understands fire problems and the different alarm and detection options.
FIRE SPRINKLERS:
For most fires, water represents the ideal extinguishing agent. Fire sprinklers utilize water by direct application onto flames and heat, which causes cooling of the combustion process and prevents ignition of adjacent combustibles. They are most effective during the fire's initial flame growth stage, while the fire is relatively easy to control. A properly selected sprinkler will detect the fire's heat, initiate alarm, and begin suppression within moments after flames appear. In most instances sprinklers will control fire advancement within a few minutes of their activation, which will in turn result in significantly less damage than otherwise would happen without sprinklers.
POWER SUPPLY:
In this type we are using 5v, 12v power supply for op-amp and relay for the fire detection purpose. We use rectifier for thee purpose of converting A.C, in to D.C and a step down transformer to step down the voltage. In smoothing, the data points of a signal are modified so that individual points that are higher than the immediately adjacent points (presumably because of noise) are reduced, and points that are lower than the adjacent points are increased. This naturally leads to a smoother signal. As long as the true underlying signal is actually smooth, then the true signal will not be much distorted by smoothing, but the noise will be reduced.
The purpose of a voltage regulator is to keep the voltage in a circuit relatively close to a desired value. Voltage regulators are one of the most common electronic components, since
a power supply frequently produces raw current that would otherwise damage one of the components in the circuit. Voltage regulators have a variety of specific functions, depending on their particular application. The full description of the power supply section is given in this documentation in the following sections i.e. hardware components.
FIRE DETECTOR:
A smoke detector is a device that detects smoke, typically as an indicator of fire. Commercial, industrial, and mass residential devices issue a signal to a fire alarm system, while household detectors, known as smoke alarms, generally issue a local audible and/or visual alarm from the detector itself.
OP-AMP:
An op-amp produces an output voltage that is typically hundreds of thousands times larger than the voltage difference between its input terminals. Op-amps are among the most widely used electronic devices today, being used in a vast array of consumer, industrial, and scientific devices. Many standard IC op-amps cost only a few cents in moderate production volume; however some integrated or hybrid operational amplifiers with special performance specifications may cost over $100 US in small quantities. Op-amps may be packaged as components, or used as elements of more complex integrated circuits.
RELAY:
A relay is an electrically operated switch. Many relays use an electromagnet to operate a switching mechanism mechanically, but other operating principles are also used. Relays are used where it is necessary to control a circuit by a low-power signal (with complete electrical isolation between control and controlled circuits), or where several circuits must be controlled by one signal.
SPRINKLER:
A fire sprinkler is the part of a fire sprinkler system that discharges water when the effects of a fire have been detected, such as when a predetermined temperature has been reached. A fire sprinkler system is an active fire protection measure, consisting of a water supply system, providing adequate pressure and flow rate to a water distribution piping system, onto which fire sprinklers are connected. Although historically only used in factories and large commercial buildings, home and small building systems are now available at a cost-effective price.
CIRCUIT OPERATION:
In this section we will discuss about the operation of the power supply. The input to the circuit is applied from the regulated power supply. The AC input i.e., 230V from the mains supply is step down by the transformer to 12V and is fed to a rectifier. When the switch s1 is open current doesn’t pass through the circuit. Current flows when the switch s1 is closed, and passes through the transformer which acts as a step-down transformer. It defines the number of primary windings are greater than the secondary windings. A step-down transformer has a large number of turns on its primary (input) coil which is connected to the
High voltage mains supply and a small number of turns on its secondary (output) coil to give a low output voltage. The output obtained from the rectifier is a pulsating DC voltage. So in order to get a pure DC voltage, the output voltage from the rectifier is fed to a filter to remove any AC components present even after rectification. Now, this voltage is given to a voltage regulator to obtain a pure constant dc voltage. The reduced AC voltage is rectified using the diode bridge circuit shown. In one direction of the current, two diodes will be 'on' while other two diodes will be off. In the other direction vice-versa. It is called a full-wave rectifier because it uses the entire AC wave (both positive and negative sections).