18th Edition Regs

Which of the following is not a preferred frequency as outlined in BS7671?

• 40 Hz

• 50 Hz

• 60 Hz

• 400 Hz

120 volts Dc between conductors is classified as

• Extra low voltage

• Reduced low voltage

• Low voltage

• Medium voltage

Where protection against overload is provided by a semi-enclosed (rewireable) fuse to as 3036, the current rating of the cable must be at least

• 0.725 times the current rating of the fuse

• The nominal current rating of the fuse divided by 0.725

• The same rating as the design current of the circuit

• 0.725 times the design current of the circuit

Which one of the following does not have to be considered in relation to the connection between conductors or between a conductor and other equipment?

• The material of the conductor and its insulation

• The number and shape of the wires forming the conductor

• The number of conductors to be connected together

• The type of overcurrent device protecting the cable

Which of the following cannot be used as an earth electrode?

• Underground structural metalwork embedded in foundations

• Metalwork installed in the foundations

• Earth plates or pipes

• Metallic water utility supply pipe

Where a final circuit is intended to supply one or more items of equipment, such that the total protective conductor current is likely to exceed 10 mA and the protective conductor is mechanically protected, the minimum csa for a single copper conductor should be which of the following?

• 2.5 mm²

• 4.0 mm²

• 6.0 mm²

• 10 mm²

The required test voltage for an insulation resistance test of an installation operating at a nominal voltage of 400 V is?

• 250VAC

• 500VAC

• 500 V DC

• 1000V DC

The minimum permitted degree of protection for an electric vehicle charging point installed outdoors is:

• IP44

• IP46

• IPX4

• IP24

What is the maximum number of twin socket-outlets that may connected to a ring final circuit via an unfused spur?

• 1

• 2

• Number is dependent upon the load characteristics taking diversity into account.

• Unlimited

A permanent durable label is required on every mobile or transportable unit to provide information for the electrical operative connecting up the unit on site. Which of the following items is not required on the label?

• Voltage rating

• Number of phases

• Earth loop impedance

• On-board earthing arrangement