BS 7671 Practice Paper 7

Where new materials are invented for use within electrical installations are departures permitted from BS 7671? Mark one answer.

• No

• Sometimes when the designer feels he likes the new materials

• With supporting evidence that they are a lower standard than the regulations

• Yes providing the resulting degree of safety of the installation is not less than that obtained by compliance with the regulation

Which characteristics of protective equipment is not required be determined with respect to their function including protection against the effects of? Mark one answer.

• Fault current

• No-voltage

• Overvoltage

• Under-current

Which one of these does BS 7671 NOT apply to? Mark one answer.

• Highway equipment

• Horticultural premises

• Operation and maintenance gangways

• d.c. cathodic protection systems

The cross-sectional area of conductors shall be determined for normal operating conditions and fault conditions according to? Mark one answer.

• Harmonics

• The electromagnetic interference

• The number of bunched cables in trunking

• The working height the cables are located

In the case of a voltage disturbance causing a power frequency fault voltage appearing on the LV side, between the exposed-conductive parts and earth, what symbol is used? Mark one answer.

• U₀

• U₁

• Uₓ

• Uf

What is defined here: 'An enclosure of metal other than trunking or conduit, that is used for the protection of cables drawn in after the ducting is erected'? Mark one answer.

• Cable ducting

• Cable ladder

• Cable tray

• Cable tunnel

The arrangements of current-carrying conductors shall be assessed under which of the following conditions? Mark one answer

• Abnormal operating conditions

• Normal operating conditions

• Overload operating conditions

• Primary operating conditions

Where can further information on external influence classifications be found? Mark one answer

• Chapter 30 and Appendix 2

• Chapter 31 and Appendix 3

• Chapter 34 and Appendix 4

• Chapter 51 and Appendix 5

Which of the following is an assessment of general characteristics? Mark one answer.

• The external earth fault loop impedance

• The installation general structure and its supplies

• The maximum demand required

• The type of earthing

The regulations state that every installation shall be so divided to: Mark one answer.

• Allow for easier installation

• Allow the direct energizing of a circuit intended to be isolated

• Place all final circuits on the same way

• Prevent indirect energizing of a circuit intended to be isolated