18th edition new

60.  What is the rating factor for a 70oC thermoplastic cables buried direct in the ground. Where the ambient ground temperature is 15oC?

59. What is the rating factor for a 60oC thermosetting cable installed in an ambient temperature air temperature 40oC?

58. What must junction boxes, within an electrical circuit, contain to ensure they need not be accessible for inspection?

57. Which grouping factor should be applied when a common conduit from a lighting distribution board contains four fully loaded individual circuits?

56. What is the reference method for  ‘non-sheathed cables in suspended trunking’?

55. What shall the earthing arrangement of a PEI, island mode, be connected to?

54. Which mode, for a collective PEI, supplies all current using equipment and storage systems from the public supply?

53. What must be taken into account, during installation of an over current protective device, in a Prosumer’s Electrical Installation?

52. What is the minimum number of supplementary equipotential bonding connection points required within a Group 2 medical location? 

51. What is generally considered to be the minimum depth for underground distribution circuits within a caravan park, if additional mechanical protection is not provided? 

What is the minimum degree of protection for equipment installed above a jetty, which is likely to be subjected to water waves?  

49. What is the minimum distance from a bath that socket-outlets can be installed? 

48.What protective measures may be used in zones 0 and 1 of a fountain? 

47. What distance from the floor does zone 3 of a sauna extend above zone 2? 

46.Which is one of the conditions where supplementary bonding in a bathroom may be omitted? 

45. What alternative measurements may be used if the value of earth electrode resistance is not practical?  

44. Which regulation contains the details regarding the information that is required to be made available to a person carrying out inspection and testing?  

43. Which signature are required on an Electrical Installation Certificate? 

42.What must a legible diagram, chart or table relating to a large commercial installation indicate? 

41.Which of the following would not be suitable as a source of supply for safety services? 

40. A standby generator is required to operate as a switched alternative to the system for distribution of electricity to the public.  

Which is suitable switching arrangement to prevent parallel operation with the public supply? 

39. What is the minimum CSA of a single-core, strapped copper conductor for an auxiliary control circuit? 

38. Which must NOT be used as an earth electrode? 

37. Which metallic item may NOT be used as an earth electrode?

36. Where would a Type 1 SPD usually be installed within an installation?  

35. Which device must NOT be specified for emergency switching?  

34. What percentage of triplen harmonics, above the fundamental line current, may require an increase in the cross-sectional area of the neutral conductor?  

32. A circuit has a design current of 70 A and is wired using a 30 m length of cable having a stated mV/A/m value of 2.8. What is the circuit voltage drop?

33.What is the rating factor for a cable surrounded by thermal insulation over a length of 200mm?

31. Which one of the following External Influence code for ambient temperature, is conventionally regarded as normal?

Where, within a commercial installation containing surge protection devices, must an information notice be displayed?

What duration is stated on the notice displayed at or near to an RCD?

28.What colour is used to identify the negative L- of a three wire DC power circuit?

27. What function is provided by a device intended to cut off all volage from an installation?

26.What is the required minimum impulse withstand voltage for Category II equipment where the nominal voltage of an installation is 230V?

25.What is the K factor for tinned soldered joins in copper conductor with 60^oC thermosetting insulation?

24.What must all overcurrent protective devices, without back-up protection on the supply side, be capable of?

23. Which premises would require the installation of an AFDD to protect each circuit supplying socket-outlets to BS1273?

22.What is the minimum distance from combustible materials that a 250 W spotlight can be installed where there is a danger of fire due to the nature of processed or stored materials?

21. What is the maximum value of earth fault loop impedance (z_s) for a 50 A BS EN 60898 Type C circuit-breaker protecting a 110 V single-phase reduced low voltage circuit?

20. Which source of supply is not suitable for a SELV system?

19.Which is a suitable safety source of a SELV supply?

18. What is the maximum disconnection timer for a circuit supplied at a reduced low voltage?

17. Which condition must be met where the protective measure ‘earth-free local equipotential bonding’ is to be used?

16. Which condition must apply when an installation uses more than on protective measure against faults?

15. What is the minimum distance, in any given direction, of arm’s reach when applying placing out of reach as a method of basic protection?

14.What is the highest current rating of mobile equipment, for use outdoors, that must have additional protection?

13. Which characteristic must protective devices of a fault protection in relation to circuit impedances fulfil?

12. Which supply conductor arrangement provides a three-phase and neutral supply?

11. What is the first letter of an earthing system here no live part is directly connected to earth?

10. What characteristic of equipment would need to be assessed for compatibility?

9.Which of the following describes the conductor’s arrangements in a TN-C-S earthing system?

8. Which is listed in BS 7671 as a consideration with regard to maintainability of an installation?

7. What can facilitate safe inspection, testing and maintenance of installations?

6. The figure shown illustrates a typical ring final circuit. Which arrows identifies the spur?

5. What is the light level for emergency lighting at the end of the rated operating time defined as?

4.Which is a fundamental principle when considering the cross-sectional area of conductors?

3. What part of BS7671 relates directly to functional requirements? 

2. which is within the scope of BS7671?

1.What is the maximum nominal DDC voltage covered by the requirements of BS 7671?