Protection Against Electric Shock Quiz

What does ADS stand for in the context of electrical safety?

• Automatic Disconnection of Supply

• Automatic Distribution System

• Active Disconnection System

• Advanced Distribution Supply

What are the two methods of protection against electric shock mentioned?

• Basic and Fault protection

• Advanced and Basic protection

• Fault and Circuit protection

• Circuit and Basic protection

Which of the following is NOT mentioned as a method of basic protection?

• Insulation of live parts

• Enclosures and barriers

• Earthing

• Equipment with correct IP ratings (IP2X & IP4X)

What does the Earth Fault Loop Impedance Path (TN-S) diagram represent?

• The path of electrical current in a fault condition

• The layout of a residential electrical system

• The design of a power plant

• The structure of a battery

What does a compliant Earth Fault Loop Impedance measurement ensure in an electrical system?

• Automatic disconnection of supply

• Continuous power supply

• Increased voltage

• Reduced current flow

What is the significance of the Earth Fault Loop Impedance in electrical safety?

• It ensures the circuit disconnects within the specified time during an earth fault

• It increases the power supply

• It reduces the voltage

• It stores electrical energy

For a Type C circuit-breaker with a rating of 25 amperes, what is the maximum earth fault loop impedance (Zs)?

• 0.87 ohms

• 0.68 ohms

• 0.55 ohms

• 0.44 ohms

For a Type B circuit-breaker with a rating of 6 amperes, what is the Zs value?

• 7.28 ohms

• 4.37 ohms

• 2.19 ohms

• 1.09 ohms

What is the function of a circuit breaker in an electrical system?

• To automatically disconnect the circuit during overload or fault conditions

• To increase the power supply

• To store electrical energy

• To convert AC to DC

Calculate the earth fault current that would flow in a 230 volt circuit with an earth fault loop impedance of 1.5 ohms.

• 153.33A

• 220A

• 325.8A

• 412.5A