The Fire Alarm System Engineering Essay

The Fire Alarm System Engineering EssayWe are living in a time that safety and security became one of the unavoidable requirements in all reachs of life, in the middle of technology revolution which invests to make life easier and more secure, technology has been earned by man in some fields of his life, and beca accustom of that and to make places where we live, work or even relax is more secure and safe by applying a elicit alarum constitution.As mentioned to a higher place we get out design a run off alarm system which leave alone alert user if there is an indication of a go off situation. The main aim of all manufacturers is to achieve the best and the cheapest systems.Fire alarm system is an railcarmatic system which detects if there an indication of a fire situation by catching temperature or sensing a batch, which are an indications of the changing in the environment that surrounds the system.Fire alarm system can be considered as a manual(a) system which prop eld by the user or an automatic system which departs by itself, or it can be considered both automatic and manual system.The superior general architecture of the fire systems consists of the sensors itself, the potencyling device (microcontroller or personal computers or any logic circuits), and the alarm speakers (buzzers) and in some cases it may contain an auto dialling devices to call the police or the receiveer of the building.Fire alarm systems can provide one or more of the followingNotifies the occupants.Controls all the fire alarm components in a building.Notifies persons in the surrounding area.Summons the fire service.Project Description and AimsThe main aim of this project is to design a plastic film microcontroller found fire and everyplace heat monitoring and alarm system the system give have the ability to detect crazy weed and continuously cake the temperature at any desired area and appearance it on an liquid crystal display (liquid crystal display) scre en.And when the temperature goes over a certain degree a fan testament be activated in cast to reduce the temperature and cool the place. But if that doesnt work and the temperature still increase an alarm will be activated in order to alert the persons on the surrounding area and the fan will be disabled in order to reduce the opportunity of starting a fire. as well as this alarm will be activated in tow more ways, either by the pull box heterotaxy which will activate the fire alarm manually or by the smoke detector that will detect any kind of smoke which is often an indication for the existence of fire.This fire system can be considered as a manual automatic system, it is based on many ways to alert people that attending in a certain place -where the system is activated for a fire situation the first method is sensing the temperature of the area if any increase of the temperature over a certain degree is detected by the controller it will be displayed on the LCD and the fan w ill be activated, if the temperature still increasing that will indicate a fire situation so the microcontroller will activate the alarm, the second method is by pulling the switch box manually by any user, and finally when the smoke sensor will detect a smoke in the environment the microcontroller will receive the read and will activate the alarm and display the result on the LCD.Main system componentsdelineation microcontroller as the system brain.LCD to display results from PIC microcontrollerTemperature sensor to measure the air Temperature.Smoke detector detects if there a smoke in the air.Alarm which alert in the fire situation.Switch used for manually activate or deactivate system.Fan to decrease the air Temperature.1.3 System Block Diagramfir blo.JPGFigure (1.1) System Block DiagramPIC microcontroller as shown in the figure (1.1) is can be described as the brain of the system, which receives inputs from three parts the first one is the temperature sensor, which measure the t emperature of a certain area and pass it to the PIC microcontroller which will detects the temperature whether its over a certain degree or not, if the temperature degree is less than the certain degree them PIC will display the degree on the LCD, if the temperature degree is over then the PIC microcontroller will display the temperature degree and will put the fan to work until the temperature decrease to the radiation diagram degree.But if the temperature degree still increasing then the PIC will consider a fire situation activate the system automatically including subroutine the fan off and will put the alarm on to alert people to a fire situation, alarm cant be put on if there is not a driving circuit PIC may not be able to turn the alarm on.The second input is from smoke detector which detects if there a smoke in the air, and send the result continuously to the PIC whether there a smoke or not. And the PIC will detect the result if there is no smoke PIC will display the resul t on the LCD, but if there is smoke PIC will display the result on the LCD and will turn the alarm on to alert people to a fire situation.The third input is from the switch by which user will be able to activate or deactivate the fire system manually. If the system detects a smoke or increasing in the temperature and assumed a fire situation and there is no fire the user can deactivate the system manually, and if the user find himself in a fire situation but the system hasnt detected it yet he can activate the system manually.1.4 Plan to implementAs shown in the block diagram first the LCD screen must be connected to the PIC in order to display the desired selective information, then the information of the temperature sensor will be fed to the PIC microcontroller finished the ADC (analog to digital) peripheral of the PIC as input then it will be processed in the PIC microcontroller so it can be displayed on the LCD screen, then we will interface the smoke detector with the PIC mic rocontroller and display its lieu on the LCD screen.After that an interface must be done through a driving circuit to activate and deactivate the siren with a control signal from the PIC microcontroller, and then to make the connection of the pull box switch.Also a driving circuit has to be implemented to control the system cooling fan from the PIC microcontroller.1.5 Software ApproachSince we are designing a PIC microcontroller based system, first we need tools to program and write the package for the PIC microcontroller, so will need to use a PIC code compiler that is efficient and easy to use, so we have chosen to use (MikroBasic) compiler.Chapter TwoTheoretical Background2.1 OVERVIEWIn this chapter we are going to explain all system hard ware components and why we used them.Several hardware components are required to combine the ability of sensing the temperature degree and detecting smoke in the air with activating the system for fire lIn this chapter we will introduce all the project components with a brief about each component.The project main components arePIC microcontroller as the system brain.LCD to display results from PIC microcontrollerTemperature sensor to measure the air Temperature.Smoke detector detects if there a smoke in the air.Alarm which alert in the fire situation.Switch used for manually activate or deactivate system.Fan to decrease the air Temperature.2.2 PIC microcontrollerA microcontroller is an integrated circuit consists of simple processor which associated with support functions such(prenominal) as timers, serial and analog I/O, crystal oscillator, its memory is divided to ROM, RAM, EEPROM, PIC is designed for small or dedicated applications.PIC used to reduce size and embody comparing to the model that uses separated CPU, memory, and I/O devices PIC also provides a benefit of controlling non digital electronic systems.PIC became popular in both industrial developers and hobbyists thats because of the low cost availability , easy to program and reprogram with flash memory (EEPROM) capability.FEnasyacoubPICpic_pl.jpgFigure 2.1 (PIC microcontroller)2.2-1 Types of the PICs PinsThe Must PinsM-CLR which sloshed master clear and it active high which mean this pin works victimization 1but if its written as M-CLR that mean it is active low works using 0, the function of this pin is to reset the PIC which mean reset to the program counter to return to the beginning of the executed code. It is the PIN no. 1 in the PIC and most of the time it is connected to the Vcc logic 1 to let the PIC work.OscillatorIt is defined as a periodic fluctuation between deuce things based on changing in energy, frequency at which oscillator works is usually determined by a quartz crystal which vibrates at a frequency depends on it thickness when current is applied to it. Oscillator can combine inductors, resistors, and/or capacitors to determine the frequency. There are two types of oscillator internal oscillator, external oscilla tor such as quartz crystals.Power supplyThe main function of power supply is to provide system with fixed emf needed, the typical voltage for near PICs is (5 V) which indicates that there is a limitation on the voltage, for voice if the PIC was provided with (5.5-6 V) it will damage, less than (2.5 V) PIC will not work, (less than 4.5 and more than 2.5) it is a float assess which mean it is not a known value for the PIC. Usually no. of power pins is 4 2 pins are grounded (VSS), the other two are 5 volt (VDD).The Optional PinsThese pins are divided into groups that are called ports. Each port has a configuration register inside the PIC and it is called TRISE register which a data direction register that controls the direction of data (input or output) of each pin of that port. For example having TRISA cleared (0 which is the default) will configure all pins of PORTA as output.PIC Microcontroller (16F876A) which is best described as the brain of the system, this part were chosen f or its convenience for the project because all the components in this project must be interfaced with each in any easy and simple approach in order to save time and effort, for instance we have used an LCD screen as a human interface to display the system status, which much is easier to connect the LCD to the PIC microcontroller rather than facing an external interfacing hardware design.2.2-2 PIC 16F876APIC16F876A High-Performance reduced instruction set computing CPUOnly 35 single-word instructionsAll single-cycle instructions except for program branches, which are two-cycle.Operating speed DC 20 MHzclock input DC 200 ns instruction cycle.Up to 8K x 14 words of Flash Program retentiveness.Up to 368 x 8 bytes of Data Memory (RAM)Up to 256 x 8 bytes of EEPROM Data Memory.Those features result because of the PIC technology CMOS TechnologyLow-power, high-speed Flash/EEPROM technology.Fully static design.Wide operating voltage range (2.0V to 5.5V).Commercial and Industrial temperatu re ranges.Low-power consumption.2.3 Liquid Crystal discover (LCD)2.3-1 Definition and Mechanism of LCDLCD is the short of a Liquid Crystal Display which is a thin, flat panel. LCD is an electronically displayer for information which can be a text, symbols, moments, images or moving pictures. It can be used as a monitor for computers, TVs, gaming devices, calculators, etc. figure (3.13) shows a 16-2 LCD.Character LCDFigure (2.2) LCD2.3-2 LCD BasicsSimple LCDs consists of liquid crustal booth surrounded by conductive electrode, upper and lower glass, upper and lower polarizer, as shown on the figure.Figure 2.3 (LCD structure)LCD displays utilize two sheets of polarizing material with a liquid crystal between them. When an electric current passed through the liquid crystal causes the crystals to align. Because of that light will not be able to pass through them. Therefore, each crystal is like a shutter, either allowing light to pass through or blocking the light as you can see in f igure (3.14).Because its low electrical power consumption which allows it to be used in battery powered electronic equipment it made of any number of pixels alter with liquid crystal cells, to produce image in colours or monochrome pixels must be arrayed in front of light source.Among to its whippersnapper construction, its portability, and its ability to be produced in much larger screen sizes than are practical construction of cathode ray tube (CRT) display technology which are LCDs major(ip) features . Also its low electrical power consumption enables it to be used in battery-powered electronic equipment.Since all the functions such as display RAM, vitrine generator and liquid crystal driver, required for driving a dot-matrix liquid crystal display are internally provided on one chip, a nominal system can be interfaced with this controller drive.LCD (Liquid Crystal Display) screen that will be used to display the temperature and to display the status of the system, we have cho sen an LCD screen since its the best way to inform the user about the system status in a friendly and simple way.2.4 Temperature SensorWhich is a device used to sense temperature also known as measurement temperature device. Temperature sensors can be classified into two types contact and non-contact sensors.2.4-1 Contact sensorsWhich measure its own temperature as the environments temperature, by considering that the sensor and the object are at the in thermic equilibrium which means that there is no flow temperature between them.2.4-2 Non-contact sensorsWhich receives thermal radiant power of infrared radiation radiates from some area, then its measure it as the temperature of that area.Temperature Sensor (LM35 DZ) this sensor has been chosen due to its high quality, sensitivity, low cost and its simple and easy output interface.Features of temperature Sensor (LM35 DZ)Calibrated directly in Celsius (Centigrade)0.5C accuracyRated for full -55 to +150C rangeFor remote applications this sensor is suitableIt can operate from 4 to 30 voltsThe current drain is less than 60 A2.5 Smoke DetectorIts been used to detect smoke in the air and fed back the result to the system. There are two methods to detect smoke in the airPhotoelectric method which also called optical detection. By emitting electronics from a matter such as liquid metals or gases that from electromagnetic radiation electrons energy would be absorptive, then the emitted electronics will be detected by the detector. The process is done as a light beam which goes in front to the light sensor in the case of no smoke, but if there smoke light will reflect in angles then light beams will be scattered to the light sensor which will consider it as a smoke setuation.http//upload.wikimedia.org/wikipedia/commons/thumb/f/f5/Photoelectric_effect.svg/275px-Photoelectric_effect.svg.png http//upload.wikimedia.org/wikipedia/commons/thumb/4/49/OpticalSmokeDetector.png/250px-OpticalSmokeDetector.pngIonization by convert ing an ion into molecule by removing or adding charges electrons. The principle of this method is that a chamber which includes two electrodes with air between them and there is a small constant current will be permitted but if there a smoke enters the ionic chamber then the small current will be interrupted which will indicate a fire situation.http//upload.wikimedia.org/wikipedia/en/thumb/6/68/Smokealarm.JPG/250px-Smokealarm.JPGhttp//en.wikipedia.org/wiki/Smoke_detector2.6 SwitchThis is an electrical device used to pass or not pass current. It is used to activate the system manually by any user in any emergency case. Or deactivate the system manually by the user in if the system activate automatically and there is no emergency case.2.7 Buzzer or sirenIs also called a beeper which is an electronic device which consists number of sensors or switches, has many applications such as car horn, clock alarm etcThat is used to inform the persons at the surrounding area and notify them about status of the fire alarm system.2.8 Driving circuitWhich is an electrical circuit by which an electronic device can control another device, driving circuit for example can be used to amplify current.