DESIGN AND CONSTRUCTION OF FIRE ALARM SYSTEM IN A THW STOREYED BUILDING
1.1 BACKGROUND OF PROBLEM
Fire detection system are safety system. They monitor rooms and buildings continuously for indication of fire outbreak and give alarm directly if one occurs.The industrial Electronics has changed the whole field ofEngineering and technology is occurring so rapidly, even indeveloping countries. It is so because newer technologies overcome older ones. After the industrial revolution the world directed towards the information age with the development of computers during the 1950’s.
As such, mechantronics which is a principle that combines theapplication of mechanical and electrical means has taken over thegreater part of industrial electronics which is indispensable in modern technology.
In Nigeria, security which is one of the basic lookouts in anyproductive firm has been on the decrease. Most industries have gone bankrupt because of their inability to meet up to the security standard required in a modern day setting. Equally, some homes and offices have lost important documents and properties due to easy access that criminals have. There is thus an urgent need for significant security measures to improve the standard of living of the people, enhance development and put to a stop the menace of insecurity. That is the reason as a student of Electrical/Electronics Engineering I decided to embark on a project named “Microcontroller Based Multipurpose Security Device with Direction”.
This electronic system consists of four sensors made up of opto couplers realized with combination of Laser beam, from Laser diode coupled into a cadmium sulfide photocell (c.d.s photocell).
This component serves as an electronic eye, the output ofoptocouplers conditioned by a Schmitt trigger NAND gate controlLogic (74 Ls 132) TTL chip. The output of the 132 chips is sent intoport 0 of 8051 microcontroller. A keypad encoder containing eightkeys is interfaced to a port 1 of 8051 microcontroller. Anelectromagnetic relay driven by a Darlington pair transistor static switch is interfaced to the port 2 of the microcontroller. Servo motors that serve as the door prime mover is link to AC Circuit. Via the normally open contact of the electromagnetic relay. A buzzer is also interface to port 2 through a single transistor static switch.
Both the British Factory Acts 1961 and the officers shops and railway premises Acts 1963 stiputed minimum requirements in the case of fire that there shall be clear and audible warning throughout the building. Also, an earlier statutory requirement (section 36 of the factories Acts 1937) states that in any factory, hospitals, market places, homes etc. Where more than 20 persons are employed that place should be effective provision for giving warning signal in case of fire outbreak and that it shall be clearly audible throughout the building.
1.2 STRUCTURE OF THE PROBLEM
The alarm is given locally (visually and audibly) in order to mobilize internal auxiliary personal e.g the works fire brigade) and inform them as to the seat of the fire. A control center performs the organization of the alarm, that is, it makes available operational aids for the fire fighting measures and automatically bring the fire protection equipment into operation.