electrical wiring

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1.0 TITLE OF THE EXPERIMENT Electrical Wiring

2.0 INTRODUCTION Electrical wiring in general refers to insulated conductors used to carry electricity and associated devices. General aspects of electrical wiring are used to provide power in or to building or structures, commonly referred to as building wiring. Electrical wiring whether for residential, commercial or industrial projects must be carefully installed and maintained in such a way it will provide safety to persons and property. This requires good workmanship, knowledge of electrical principles and circuitry. Familiarity with electrical wiring accessories in an important provision beside an awareness of and strict adherence to the provisions of the National Electrical Code (NEC). The surface wiring is the basic wiring that has been used for many purposes. Usually, this type of wiring does not have any problem encountered such as the view, the alignment and many other aspects. It is the wiring which is installed and can be seen with bare eyes. Concealed wiring is wiring that is covered by the finish of the building and therefore considered as inaccessible. It is usually for single phase supply of electricity. Building of bricks or concrete is suitable for this type. The mechanical damages can be avoided. There are many installations. It is also high durability of cables required, small power consumption and usually uses PVC insulated conduits. An electrical conduit is a purpose designed electrical piping system used for protection and routing electrical wiring. Electrical conduit may be made of metal, plastic, fiber or fired clay. Flexible conduit is also available for special purpose. Conduit is generally installed by electricians at the installation of electrical equipment. Its use, form and installation details are often specified by wiring regulations such as NEC or other national or local code.

3.0 OBJECTIVES To identify the process of electrical wiring installation for the single storey house as given in the laboratory. To review and discuss all the process of electrical wiring installation for the single storey house. To prepare the schematic diagram for the electrical wiring installation.

4.0 APPARATUS Electrical wiring sample board Test span Camera

5.0 PROCEDURE 5.1 Components of electrical wiring at the sample board were indentified. 5.2 The suggestions of the electrical devices accessories that suitable to the electrical wiring installation were made. 5.3 The schematic diagram of electrical wiring installation was sketched.

6.0 LITERATURE REVIEW

6.1 Distribution Board (DB) A distribution board (or panelboard) is a component of an electricity supply system which divides an electrical power feed into subsidiary circuits, while providing a protective fuse or circuit breaker for each circuit, in a common enclosure. Normally, a main switch, and in recent boards, one or more Residual-current devices (RCD) or Residual Current Breakers with Overcurrent protection (RCBO), will also be incorporated. (Wikipedia-Distribution Board) 6.2 Moulded Case Circuit Breaker (MCCB) These all-in-one components sit neatly inside the main electrical panel of your home and business and perform their service quietly, only to make themselves known when they have performed the task of over-current protection. Molded case circuit breakers are manufactured in such a way so the end user will not have access to the internal workings of the over-current protection device. Generally constructed of two pieces of heavy-duty electrically insulated plastic, these two halves are riveted together to form the whole. Inside the plastic shell is a series of thermal elements and a spring-loaded trigger. When the thermal element gets too warm, from an over-current situation, the spring trips, which in turn will shut off the electrical circuit. (http://www.ehow.com) 6.3 Earth Leakage Circuit Breaker (ELCB) An Earth Leakage Circuit Breaker (ELCB) (now referred to as residual current circuit breaker) is a safety device used in electrical installations with high earth impedance to prevent shock. The main purpose of earth leakage protectors is to prevent injury to humans and animals due to electric shock. ELCBs have one advantage over RCDs: they are less sensitive to fault conditions, and therefore have fewer nuisance trips. (This does not mean they always do, as practical performance depends on installation details and the discrimination enhancing filtering in the ELCB.) Therefore by electrically separating cable armour from cable CPC, an ELCB can be arranged to protect against cable damage only, and not trip on faults in downline installations.

6.4 Miniature Circuit Breaker (MCB) The term "miniature circuit breaker" refers to any circuit breaker used in electrical panels found in residences or light commercial businesses. Like all circuit breakers, miniature circuit breakers regulate the amp flow through a specific circuit; they simply allow less than industrial circuit breakers. Homeowners need to understand proper circuit identification and troubleshooting techniques to ensure correct use of miniature circuit breakers as a safeguarding measure.

7.0 RESULT ITEM GANG M/C SOCKET FUNCTION Device commonly employed in domestic installation to facilitate the connection to the main supply of portable lighting fitting and others appliances. It is fixed and design to receive a plug that carries protruding metal contacts corresponding to recessed contact in he socket outlet FAN REGULATOR To control the current that flow to the fan. The higher the speed of the fan, the lasses resistance in the current flow. FLUORECENT LAMP This is low pressure variation of the mercury discharge energized mercury atoms emit ultra violet radiation and a blue light. Provide a combination of radiation and ultraviolet light Important component installation. in visible

BULB

WIRE

electrical

Connect the power sources(electricity) and the equipment that use it. The type of wire depends on the method used/adopted. *Wire :Red - live *Wire Green - earth *Wire Black - neutral wire EARTH LEAKAGE CURCUIT BREAKER safety device used in electrical installations with high earth impedance to prevent shock. The main purpose of earth leakage protectors is to prevent injury to humans and animals due to electric shock

DIRECT ON LINE STARTER

Act as the switch to the air conditioner. Let the current flow to the air conditioner

8.0 DISCUSSION CURRENT SUPPLY FOR THE DOMESTIC BUILDING i-ELECTRIC POWER GENERATION After electricity is produced at power plants is has to get to the customers that use the electricity. Our cities, towns, states and the entire country are crisis-crossed with power lines that carry the electricity. As large generators spin, they produce electricity with a voltage of about 25,000 volts. A volt is a measurement of electromotive force in electricity. The electricity first goes to a transformer at the power plant that boosts the voltage up to 400,000 volts. When electricity travels long distances it is better to have it at higher voltages (more efficiently at high voltages).The long thick cables of transmission lines are made of copper or aluminum because they have a low resistance.

High voltage transmission lines carry electricity long distances to substation. From this substation, electricity in different power levels is used to run factories, streetcars and mass transit, light street lights and stop light, and is sent to neighborhood. When electricity enters (example house), it must pass through a meter and goes through a fuse box. The fuse box protects the house in case of problems. When fuse (circuit breaker) blows or trips something wrong with an appliance or something was short circuited.

ii-ELECTRIC POWER TRANSMISSION A process in the delivery of electricity to consumers is the bulk transfer of electrical power. Typically, power transmission is between the power plant and a substation near a populated area. This process can be divided into two phases; primary transmission and secondary transmission.

(a) Primary Transmission A set of transformer at bulk transmission station- To raise the generated power (11-25kV) to the high voltages (500kV) used on the high voltage transmission lines called the National Grid. The connection in the transformers from power generated by alternator to the power supplied to the high power lines may be typed Delta to Delta or Delta to Star (Wye) or other combinations. Delta-star is commonly used because safety of additional neutral line can be incorporated.

(b) Secondary Transmission Secondary high transmission substation- Consists of step-down transformer from500kv to 33kV. The power will supply to large heavy industries and various states.

iii-ELECTRICAL POWER DISTRIBUTION Electricity distribution is the penultimate stage in the delivery (before retail) of electricity to end users. It is generally considered to include medium-voltage (less than 50 kV)power lines, electrical substations and pole mounted transformers, low voltage(less than 1000 V) distribution wiring and sometimes electricity meters. The process can be divided into two phase;

(a) Primary Distribution Substations Consists of step-down transformer from 33 kV to 11kV.These will supply the heavy consumption of high-rise commercial buildings, factories of heavy to medium consumption and large cities or suburban areas. Distribution cables on large unipole- consist of single pole of either reinforced concrete of CHS steel pole with supporting branches on both sides to supports hanging cables. Other method used is by underground due to heavy traffics.

(b) Secondary Distribution Substations Consists of step-down transformer from 11kV to 41 5kV or and 240kV.Thessubstation usually located within the housing areas, villages or towns. Distri