Chapter 16
Practical electricity
Appliance energy use and protection depend on the power, operating time and circuit connections.
Work out the electrical input and trace the current paths that explain each protective feature.
Electrical heating, kW h, supplied energy tariffs, plug wiring, live switching, fuses, earthing and double insulation. For K323 (2027) / 6091 (2026).
Choose a topic
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.