Elements describe the essential outcomes. | Performance criteria describe the performance needed to demonstrate achievement of the element. |
1 | Apply concepts of resistivity, resistance and capacitance to series and parallel AC and DC circuits | 1.1 | Calculations are performed to solve problems related to resistance, voltage drop, current and power in series and parallel circuits |
1.2 | Calculations are performed to solve problems related to temperature coefficient of resistance and change of resistance of a conductor with a change of temperature |
1.3 | Basic relationships that give total equivalent capacitance for capacitors arranged in series and parallel combinations are derived |
1.4 | Relationships that give total equivalent capacitance to solve numeric problems involving alternating current (AC) and direct current (DC) circuits are applied |
2 | Explain how principles of electrolytic action apply to electrical cells and batteries | 2.1 | Kirchhoff’s circuit laws are explained |
2.2 | Calculations to solve problems involving currents, voltage drop and terminal potential difference for cells connected to form batteries in series and in parallel are performed |
2.3 | Calculations to solve secondary cell charging and discharging problems are performed |
2.4 | Calculations to solve problems related to the efficiency of cells are performed |
3 | Analyse a magnetic circuit | 3.1 | Key parameters of magnetic circuits are identified |
3.2 | Formula for calculating the amount of flux generated by a multi turn solenoid coil carrying a current to give the B/H relationship is applied |
3.3 | Significance of the varying slopes in the B/H curves for a solenoid coil with air, cast iron, cast steel and mild steel cores is explained |
3.4 | How a magnetic circuit may be created by using a toroidal core within the solenoid coil is demonstrated |
3.5 | Calculations to solve problems relating to magnetic circuits using different materials in different parts of their cores, including air gaps, are performed |
3.6 | Effect on flux density of applying an alternating magnetising force to an iron core is shown diagrammatically |
4 | Interpret electromagnetic consequences of a conductor moving relative to a magnetic field | 4.1 | Faraday’s and Lenz’s Laws are applied to solve problems relating to the electromagnetic induction of EMF and current |
4.2 | Generation of EMF is illustrated by a simple, single loop conductor rotating in a uniform magnetic field and how this EMF may be tapped to an external circuit as either AC or DC is explained |
4.3 | How alternating electrical quantities may be represented by rotating phasors is illustrated and explained |
4.4 | Relationships between instantaneous, maximum, average and RMS values of sinusoidally alternating electrical quantities is derived |
4.5 | Mathematical problems are solved by applying relationships between instantaneous, maximum, average and RMS values of sinusoidally alternating electrical quantities |
5 | Analyse circuits that incorporate combinations of resistive, inductive, and capacitive elements | 5.1 | Time constant for different circuit combinations subjected to DC EMF’s is defined |
5.2 | Calculations are performed to solve problems involving time constants in DC circuits with changing rates of current in resistive/inductive elements and changing voltages through resistive/capacitive circuit elements |
5.3 | Differentiation is made between inductive reactance, capacitive reactance and impedance as applied to AC circuits |
5.4 | Effects of inductive and capacitive reactance upon phasor relationships between applied AC voltage and current are shown |
5.5 | Concept of total impedance is applied to solution of problems involving single phase AC quantities in the presence of both resistive/inductive and resistive/capacitive circuit elements, arranged in either series or parallel |
5.6 | Power factor is defined and concepts of real and reactive power usage are applied to solution of problems involving RL and RC elements |
6 | Analyse operation of polyphase AC circuits | 6.1 | How three phase AC may be developed out of simple single phase AC is explained |
6.2 | Voltage and current relationships between line and phase in both Star and Delta 3 phase connections are derived |
6.3 | Standard Star to Delta and Delta to Star conversion relationships for current and voltage are derived |
6.4 | Numeric problems involving both balanced and unbalanced circuit loads are solved |
6.5 | Relationships between kW, kVA and kVAr for 3 phase AC circuits is derived |
6.6 | Calculations are performed using the relationship between kW, kVA and kVAr to solve problems in 3 phase AC circuits |
7 | Describe basic operating principles of shipboard DC machinery | 7.1 | Schematic circuits are prepared for separately excited, series, shunt and compound connected generators and motors to illustrate wiring arrangements used with DC machines |
7.2 | EMF equation for a DC generator to solve shipboard problems is applied |
7.3 | Torque equation for a DC motor to solve shipboard problems is applied |
7.4 | Expression linking back EMF parameters for a DC motor is derived and used to solve shipboard problems |
7.5 | Various losses that can occur in DC motors and generators are calculated |
8 | Perform calculations related to operation of AC generators | 8.1 | Construction features of the AC synchronous generator are explained |
8.2 | EMF equation for an AC generator is derived, taking into account distribution and pitch factors |
8.3 | Expression for the magnitude and speed of the rotating flux generated by a three-phase supply is derived |
8.4 | Voltage regulation for synchronous generator is defined |
8.5 | Effect of power factor on load characteristic of an AC generator is illustrated |
9 | Perform calculations related to operation of three-phase AC induction motors | 9.1 | Construction features of the AC induction motor are explained |
9.2 | Expression for slip of an induction motor rotor is derived and applied to frequency of its rotor EMF and current |
9.3 | Expression for magnitude of rotor EMF and current is derived, taking into account distribution and pitch factors |
9.4 | Relationships between rotor torque, rotor losses and slip indicating factors that affect torque are outlined |
9.5 | Significance of torque/slip curves for an induction motor is explained |
9.6 | Relationship between starting torque and applied voltage is established and consequences of this upon starting methods are outlined |
10 | Explain operating principles of basic electrical instrumentation | 10.1 | Schematic circuit diagrams are prepared that illustrate the main features and applications of moving coil and moving iron voltmeters and ammeters |
10.2 | Schematic circuit diagrams are prepared that illustrate the main features and applications of air and iron cored dynamometer type wattmeters |
10.3 | Dangers associated with current and voltage transformers on high current and voltage systems are identified |