AFDDs and RCDs

According to BS 7671, what is the main purpose of an Arc Fault Detection Device (AFDD)?

• Detect residual currents

• Detect thermal overload

• Detect arc faults in wiring

• Prevent overvoltage

Where is the installation of AFDDs recommended by BS 7671?

• Industrial switch rooms

• Domestic kitchens

• Premises with sleeping accommodation

• Agricultural buildings

An RCD is designed to disconnect the supply in the event of which of the following?

• Overcurrent

• Earth fault

• Overvoltage

• Short circuit

What is the typical operating current of a 30 mA RCD used for additional protection?

• <10 mA

• 30 mA

• 18-28 mA

• 100 mA

BS 7671 requires RCDs for socket-outlets with a rated current not exceeding...

• 5A

• 16A

• 32A

• 63A

What is the correct answer for the given options?

• 13 A

• 16 A

• 20 A

• 32 A

AFDDs should conform to which standard?

• BS EN 61009

• BS EN 62606

• BS EN 61439

• BS EN 60309

Which type of RCD can detect smooth DC residual currents?

• Type AC

• Type A

• Type F

• Type B

What is the maximum disconnection time for final circuits ≤32 A in a TN system?

• 0.1 s

• 0.2 s

• 0.4 s

• 5 s

An RCD should operate within what time during a 5x IΔn test (e.g. 150 mA for a 30 mA RCD)?

• 200 ms

• 100 ms

• 40 ms

• 300 ms