BS 7671 18th Edition Part 1&2 practice questions

Which of the following is not a preferred frequency as outlined in BS 7671?

• 40 Hz

• 50 Hz

• 60 Hz

• 400 Hz

Answer explanation

110.1.2

Which person makes the recommendation for the interval to the first periodic inspection and testing of an electrical installation?

• The person ordering the work

• The designer

• The installer

• The person carrying out the initial verification

Answer explanation

134.2.2

BS 7671 does not apply to electrical installations of:

• Construction sites

• Ships

• Caravans

• Electric vehicle charging points

Answer explanation

110.1.1 & 110.2

To which of the following do the requirements of BS 7671 apply?

• Installations in mines

• Offshore installations

• Public transmission systems

• Caravans and their sites

Answer explanation

110.1.1

A system is defined as:

• The kWh meter and an installation

• The distribution cables to an installation

• The consumers terminals of an installation

• A single source or multiple sources of electrical energy and an installation

Answer explanation

Part 2 : System

120 volts DC between conductors is classified as:

• Extra-low voltage

• Reduced low voltage

• Low voltage

• Medium voltage

Answer explanation

Part 2 : Extra-low voltage