Chapter 14
Practical electricity
Appliance energy use and protection depend on the power, operating time and circuit connections.
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Electrical heating and power
Connect electrical input to heating, and calculate power and energy from matching readings.
Energy use and cost
Use kW h, operating time and a supplied tariff to calculate an appliance cost.
Live, neutral, earth and the plug
Identify the conductors and plug parts, and explain why a switch interrupts the live connection.
Hazards and protective devices
Explain damaged-insulation, overheating and damp-condition hazards, then trace how protection works.