Electrical Installation

course outline

Topics

• WORKSHOP SAFETY RULES AND REGULATIONS

  This module covers essential safety practices and regulations in electrical workshops to ensure a safe working environment.

• Hazards in electrical workshop

  Covers causes of accidents, prevention of accidents and precautions to be taken.

• Dangers in electrical workshop

  Dangers arising as a result of faulty equipment and tools, chemicals, water, poor joint and insulation strains and moving machines.

• First-aid for electrical accidents

  Covers contents of first-aid box, treatment for cuts, burns and electrical shock, and procedures for first aid (e.g. removing casualty from contact with live wire and administering artificial respiration).

• Statutory regulations

  Focuses on various statutory regulations (electricity supply regulations, factory acts and IEE regulations), their importance, aims, objectives, and applications.

• ELECTRICAL INSTALLATION TOOLS, MATERIALS AND ACCESSORIES

  This module introduces various tools, materials, and accessories essential for electrical installation work.

• Measuring, marking and striking tools

  Types and uses of measuring instruments. Types and uses of marking and striking tools.

• Types and preparation of cables

  Includes types, sizes and preparation of cables. Types of armoured cables, reasons for armouring, parts of armoured cables, joints and terminations of armoured cables. Types of data cables (e.g. computer cable, fibre optics and co-axial cable) and their uses. Other types of cables (sheathed, screaned or H-type, gas pressured impregnated and MICC cables).

• Electrical accessories

  Types of electrical accessories (switches, sockets, lamp holders, ceiling roses, joint boxes, plugs etc.) and their uses. Regulations guiding their uses.

• Cells

  Covers types of cells (primary and secondary), working principles of cells and construction of a simple cell.

• WORKSHOP PRACTICE

  This extensive module covers practical aspects of electrical installation, from drawing and wiring to machine installation and testing.

• Working drawing

  Draw and identify electrical BS symbols (switches, lamp holders, sockets, cooker control units etc.).

• Generation, transmission and distribution systems

  Drawing and interpretation of circuit diagrams of generation, transmission and distribution systems. Wiring drawing and scale drawing of a living room.

• Surface wiring

  Materials for surface wiring (cables-1mm², 1.5mm², clips, nails etc.). Tools for surface wiring (hammers, screw drivers, pliers etc.). Factors affecting current rating of cables (e.g. types of conductors, ambient temperature and types of excess current protection). Wiring a point of light controlled from two independent positions.

• Conduit wiring

  Explanation of conduit wiring, types (e.g. PVC, galvanized, surface and concealed), advantages and disadvantages. Identification and uses of conduit wiring. Procedures for conduit installation (piping, wiring and fitting). Types of conduit boxes and fittings (end box, angle, tee-4-way, 2-hole loop-in, junction box, knock-out box, couplers etc.). Tools for conduit wiring (bending spring, bending machine, hammer, chisel, hacksaw stove etc.). Materials for conduit wiring (union gum, conduit box, conduit pipes etc.).

• Illumination

  Concept of illumination. Factors affecting illumination. Definition of illumination, luminous flux and luminous intensity. Types of lamps. Mathematical calculation on illumination. Measurement of illumination using the photometer.

• Soldering

  Types of solders and fluxes. Operations and maintenance of blow-lamps. The use of pot and ladle in soldering cable of big sizes. Soldering of joints. Types of conducting materials (e.g. copper, aluminum and silver) and their advantages and disadvantages. Significance of heat transfer on conductors.

• Joints and termination of cables

  Tools and materials used in cable jointing; e.g. soldering bit, blow-lamp, solder, soldering iron, propane gas, pot and ladle, insulated wire and flux. Types of insulating materials (e.g. PVC rubber, paper, mica and bakelite). Types of joints (e.g. tee, married, twist, telescope and scarf). Preparation of cable for joints and terminations.

• Installation - MICC cable, trunking and ducting

  MICC cable, preparations of MICC cable for termination. Tools and materials used in MICC installation. Advantages and disadvantages of MICC. Simple surface and industrial installation. Types of bus-bar trunking, fabrication of ducts and trunking accessories. Requirements of IEE regulations on MICC, trunking and ducting.

• Underground cable installation

  Types of cable for underground electrical installation work; e.g. sheathed, screened or H-type and gas pressured impregnated. Trench preparation, laying of underground cables, tools and materials for underground cable installation. IEE regulations for underground cable installation.

• Overhead wire installation

  Tools, cables/wires and equipment used in overhead distribution/transmission. Types of insulation used for overhead distribution/transmission. Types and uses of stay wires. Drawing of lines and cross-arms. Joints and terminations and electrical continuity.

• Inspection and testing of domestic installation

  Types and sequence of test; e.g. polarity, insulation resistance, earthing and continuity of ring circuit. Importance of testing and inspection. Instruments for testing; e.g. Insulator resistance Tester (megger), bell set and ohmmeter.

• D.C machines

  D.C motors and generators—types, identification, constructional features, operations and applications.

• A.C machines

  A.C motors and generators—types, identification, constructional features, operations and applications. Differences between D.C and A.C motors; D.C and A.C generators.

• Installation of machines

  Types of enclosure and their applications. Selection of suitable starter for different motors; (e.g. star-delta, direct-on-line and auto transformer) and their principles of operations. Test for correct rotation, short circuit and earth fault. Installation of AC and DC machines.

• Tools and equipment for rewinding jobs

  Identification of tools and equipment for rewinding jobs; (hammers screwdrivers spanners, crimpings, winding machine, mallets etc.).

• Winding drawing

  Drawing and interpretation of simple wave and lap windings. Application of simple wave and lap windings. Determination of coil span per pitch, per phase, per pole. Identification of the position of coil ends on commutator/slip rings for fixed brush on a winding diagram.

• Rewinding of single phase electric motor

  Sizes of conductors and types of insulating materials used in winding. Connection of winding coil using prepared data. Continuity and earthing test.

• Armature, commutator and slip rings

  Skimming of armature, slip rings and commutator-under-cutting. Effectiveness of commutators.

• PROTECTIVE DEVICES AND MAINTENANCE

  This module covers the installation of protective devices and various aspects of electrical equipment maintenance.

• Installation of protective devices

  Protective devices (fuses and circuit breakers—voltage and current operated). Working principles and application of fuses and circuit breakers. Regulation guiding installation of protective devices.

• Maintenance of electrical equipment

  Types of maintenance (preventive and corrective). Procedures for machine and equipment maintenance. Grades of lubricants and their application. Constructional features of some electrical appliances (electric heater, boiler, pressing iron etc.).

• Dismantling and assembling of machines

  Procedures for dismantling machines. Methods of collecting data from the name plate. Assembling of machine parts.

• Repair of electrical machines, equipment and installation

  Causes of faults and breakdown. Signs and symptoms of faults and breakdown. Interpretation of circuit diagrams. Trouble shooting techniques (e.g. detection of bad bearing and other parts). Inspection and testing of machines (e.g. performance test).

• ENTREPRENEURSHIP IN ELECTRICAL INSTALLATION

  This module provides essential knowledge for setting up and managing a small scale business in electrical installation.