Electrical Quiz

How much current would flow in a circuit having 10Ω resistance on a 230 Volt supply?

• 2.3 A

• 23 A

• 230 A

• 2300 A

How much current would be drawn by a 3KW, 230V water heater?

• 0.07 A

• 0.76 A

• 1.30 A

• 13.0 A

Answer explanation

To find the current (I), use the formula P = V × I. Rearranging gives I = P / V. For a 3KW (3000W) heater at 230V, I = 3000W / 230V = 13.0 A. Thus, the correct answer is 13.0 A.

Which non-statutory document gives requirements for Electrical Installations?

• GS38

• BS 7671

• HSWA

• EWR

Answer explanation

BS 7671, also known as the IET Wiring Regulations, provides the non-statutory requirements for electrical installations in the UK, ensuring safety and compliance. The other options do not serve this purpose.

What does RCD stand for?

• Reacting circuit device

• Resistive current deactivator

• Residual current device

• Remote circuit deactivator

Answer explanation

RCD stands for Residual Current Device, which is a safety device that cuts off electrical supply in case of a fault, preventing electric shocks and fire hazards. The other options do not accurately describe this device.

What are the identification colours of the two conductors connected to the micro-switch within a zone valve?

• Orange & Grey

• Blue & Brown

• Blue & Orange

• Brown & Grey

Answer explanation

The identification colours for the conductors connected to the micro-switch in a zone valve are Blue & Brown. This standard colour coding helps in correctly identifying the live and neutral connections.

What coloured conductors are classed as live?

• Green

• Yellow

• Brown and Blue

• Yellow and Green

Answer explanation

In electrical wiring, the brown conductor is typically used for live (phase) connections, while blue is used for neutral. Therefore, the correct answer is 'Brown and Blue' as they are classed as live conductors.

What is the frequency of the electrical supply to the UK?

• 20Hz

• 50Hz

• 60Hz

• 100Hz

Answer explanation

The standard frequency of electrical supply in the UK is 50Hz. This is the frequency at which alternating current (AC) is supplied to homes and businesses, making 50Hz the correct answer.

What type of drawing shows the location of electrical accessories within a building?

• Plan drawing

• Wiring diagram

• Circuit diagram

• Schematic drawing

Answer explanation

A wiring diagram specifically illustrates the location and connections of electrical accessories within a building, making it the correct choice. Other options like circuit diagrams and schematic drawings serve different purposes.

What rating of circuit breaker should be used to protect a 230V, 9KW shower circuit?

• 20A

• 32A

• 40A

• 50A

Answer explanation

To find the circuit breaker rating, divide the power (9000W) by the voltage (230V), which gives approximately 39.13A. The nearest standard rating is 40A, making it the correct choice to protect the shower circuit.

Which of the following are the 3 parts of a cable?

• Conductor, Insulation, Sheath

• Core, Jacket, Shield

• Wire, Cover, Protector

• Fiber, Coating, Layer

Answer explanation

The correct answer is 'Conductor, Insulation, Sheath' as these are the essential parts of a cable. The conductor carries the electrical signal, insulation protects it, and the sheath provides additional protection and structure.