ABSTRACT
At the end of this chapter you should be able to:
• recognize common electrical circuit diagram symbols
• understand that electric current is the rate of movement of charge and is measured in amperes
• appreciate that the unit of charge is the coulomb
• calculate charge or quantity of electricityQ fromQ= It • understand that a two points in a circuit is required for current to flow
• appreciate that the
• understand that and is measured in ohms
• appreciate what an a multimeter, an oscilloscope, a wattmeter, a bridge megger, a
• distinguish between
• state Ohm’s law as
• use Ohm’s law in and sub-multiples of units
• describe a conductor of each
• appreciate that = VI = I 2R = V 2
R watts
• calculate electrical power
• define electrical energy and state its unit
• calculate electrical energy
• state the three main effects of an electric current, giving practical examples of each
• explain the importance of fuses in electrical circuits
• appreciate the dangers of constant high current flow with insulation materials
Symbols are used for components in electrical circuit diagrams and some of themore commonones are shown in Figure 4.1.
