Electrical Installation Quiz

State three human resource factors that will require monitoring during an electrical installation project.

• Team skills, availability, and conflict resolution

• Budget, project timeline, and equipment

• Client satisfaction, supplier contracts, and external risks

• Weather conditions, site accessibility, and material quality

Which of the following is NOT a principle of operating a wind turbine?

• Wind Turbine converts kinetic energy from the wind into mechanical energy.

• Gear box increases the rotational speed for the generator.

• Generator converts mechanical energy into electrical energy.

• Wind Turbine operates solely on solar energy.

A 0.318 H inductor has a resistance of 20 Ω and is connected in series with a capacitor of 38.9 μF. They are connected to an AC 230 V supply at 50 Hz. Calculate the circuit’s power factor.

• 0.95

• 0.85

• 0.75

• 0.65

When a voltage of 110 V is applied to a circuit, a current of 20 A flows at a power factor of 0.95. Calculate the kVA.

• 2.31 kVA

• 11 kVA

• 20.9 kVA

• 22 kVA

An inductor has an inductive reactance of 4 kΩ when it is connected across a 24 V, 50 kHz AC supply. Calculate the supply current.

• 0.006 A

• 6 mA

• 60 mA

• 600 mA

How does the wound rotor on an AC induction motor achieve a high starting torque?

• By increasing the resistance in the rotor circuit

• By decreasing the resistance in the rotor circuit

• By maintaining a constant resistance in the rotor circuit

• By eliminating the rotor circuit

Which of the following are the three principles of space heating?

• Conduction, Convection, Radiation

• Conduction, Insulation, Ventilation

• Radiation, Insulation, Convection

• Ventilation, Radiation, Conduction

Describe the operating principle of a thermostat in an immersion heater.

• It uses a magnetic field to heat the water

• It converts electrical energy directly into heat without any medium

• It regulates the temperature by switching the heating element on and off

• It increases the pressure inside the tank to heat the water

Determine a suitable type and nominal rating of protective device for a single-phase circuit supplying a total loading of 4000 W discharge lighting.

• Type B, 20 A

• Type C, 16 A

• Type D, 25 A

• Type B, 25 A

Which of the following are the two methods used to determine the suitability of a protective conductor CSA for thermal constraints during earth fault conditions as given in BS 7671?

• Adiabatic equation and Protective device operation

• Protective device operation and Load capacity

• Load capacity and Environmental factors

• Environmental factors and Adiabatic equation