Electricity - Senior 1 and 2

Safety

Candidates will be expected to acquire and employ safe-working procedures with respect to:

(a) Behavior and dress while working in the shop.

(b) Movement and storage of materials, tools, and equipment.

(c) Fire prevention and procedure in the even of fire and an accident.

(d) When working on electricity apparatus or electrical systems which have voltage present.

(e) Shock treatment.

Drawing

Candidates should be able to use and read electrical circuits and symbols including the:

(a) Identification and use of basic electrical symbols.

(b) Identification and drawing of series and parallel circuits.

(c) Simple first and third angle orthographic drawings.

(d) Simple pictorial drawings in isometric and oblique.

(e) Transfer of dimensions between pictorial views, orthographic views and an actual model.

(f) Express themselves by means of free-hand sketching using the techniques referred to in (c), (d) and (e).

(g) Understanding and the use of sketched drawings using scales of: (i) twice full size; (ii) full size, (iii) half-full size.

(h) Drawing up lists of materials.

(i) Work from given procedure notes and also using their own.

Occupational Information

Candidates will be expected to be familiar with:

(a) Occupations related to the electrical industry in Uganda including wages, working conditions, recruitment and training requirements.

(b) Transfer to post-Secondary Technical Institutions, H.S.C. etc.

Energy Sources

(a) What is electricity? Production of electricity. How heat, friction light, pressure, magnetism and chemical action produce electricity.

(b) Dry cells.

(c) Hydro-electric energy.

(d) Coal.

(e) Diesel.

(f) Solar.

(g) The difference between A.C. and D.C.

Materials

Candidates should be familiar with the more common electrical components and be able to identify and use them.

Marking Out and Measuring Tools

Candidates will be expected to have a knowledge of and use of the following:

(a) Ammeter

(b) Voltmeter

(c) Ohmmeter

Electrical Circuits (D.C.)

Candidates will be expected to describe and identify, as well as employ in a laboratory situation, the following:

(a) Batteries

(b) Conductors

(c) Insulators

(d) Lamps

(e) Switches

(f) Terminals

(g) Simple Circuits

(h) Ohm's law governing voltage, resistance and current in D.C. circuits.

Tools

Candidates are expected to know the use of the following tools:

(a) Wire gauge

(b) Screwdrivers

(c) Diagonal pliers

(d) Soldering gun

(e) Wire stripper

Wire Connections

(a) Soldering simple end-to-end wire connection.

(b) Soldering wire lugs.

(c) Soldering wire ends to be connected into electrical appliances both with single strand and multiple strand wire, wire wrapping.

Magnets and Electromagnets

Candidates will be expected to describe, examine, employ and construct where applicable the following in a laboratory situation:

(a) Bar magnets (repulsion and attraction).

(b) Magnetic field about a current carrying conductor.

(c) Electromagnet.

(d) Buzzer, Bell

(e) Relay

(f) Relay applications such as telegraph circuit.

Wire Connection to Appliances

Connecting plugs to cords. Connecting cores to electrical appliances such as irons, radios, cookers,etc.

- Emphasis on safety: always switch off and unplug appliances

- International Color Coding:

(1) Live = Brown

(2) Neutral = Blue

(3) Earth/Ground = Yellow-Green

Circuit Building

Two-way switching system including time switching. Construction of simple electric circuit on wooden board and using low voltage supply (dry cells or car battery), bulb, switch and wire.

- Size and construction should provide for future extension of circuit.

Flow of Current

(a) The flow of a current and what it is.

(b) Measuring current. How a meter works, how to read the scale of a meter.

(c) What causes the current to flow.

(d) How potential difference is measured.

Measuring Voltage and its Application

(a) Handling a voltmeter in circuit of previously constructed circuit board (parallel connection).

(b) Measurement of various other low voltage supplies.

(c) Observing influence of changing strength of bulb on supply voltage (no explanation of results of internal resistance yet).

Parallel Connection and its Application

(a) Addition of one bulb parallel to the first one in the board circuit.

(b) Measuring total current and current through each bulb individually.

(c) Measuring voltage across each lamp.

Series Connection and its Application

(a) Adding a second lamp to the breadboard circuit in series with the first one.

(b) Measuring total voltage and voltage across each bulb individually.

(c) Measuring current through each branch.

Determination of Resistance With Ohm's Law

(a) Determination of the resistance of resistors, bulbs and other devices through measuring current and voltage and calculations with Ohm's law.

(b) Series circuits.

(c) Parallel circuits.

(d) Series parallel circuits.

Circuit Tester (Compound Project)

(a) Construction of individual portable circuit tester with battery holder of easy replacement of cells. Indicator can either be a lamp, bell or buzzer.

(b) Using circuit tester to pinpoint short and open circuits.

- Construction of housing, hardware, etc. may involve woodwork, metalwork and technical drawing.

240V Testing Circuit

Design and construction of 240-Volt breadboard circuit containing:

(a) Fuse holder and fuse.

(b) Toggle switch.

(c) Lamp holder

(d) Four binding posts for easy connection of ammeter and voltmeter.

(e) Measuring current through various appliances to be plugged into the socket outline.

Fault Finding and Electrical Appliances

Using circuit tester finding:

(a) Theory about fault finding.

(b) Short circuits in plugs.

(c) Short circuits in leads.

(d) Broken wire in cord.

(e) Wrong connection in appliance cord.

(f) Shorts to ground.

Lamp Stand (Compound Project)

Construction of table lamp.

Wood work: base and stand

Metal work: shade of iron wire (to be covered with cloth).

Electricity: installation of lamp holder and switch and wiring up.

Design: Each student should make his own design.

- Alternatively, a fancy bottle could be used instead of a wooden base.