C & G 2382-18;  revision paper C


1. BS 7671 does not apply to

a)    Caravan parks

b)    photovoltaic systems

c)    railway signaling equipment

d)    prefabricated buildings.


2.  The choice and type of wiring system shall include consideration of

a)    design current

b)    the earth loop impedance external to the installation

c)    the type of earthing system

d)    accessibility of wiring to persons and livestock



3.  Part of medical electrical equipment that in normal use necessarily comes into physical contact with the patient is called

a)    Medical electrical equipment

b)    Applied part

c)    Double insulated part

d)    Reduced low voltage equipment

4. A transient wave appearing as an overcurrent caused by a lightning electromagnetic impulse is known as

a)    A surge current

b)    A short circuit current

c)    An overvoltage

d)    A harmonic current.


5  Which of the following is not recognized as a source for safety services

a)    Primary cells

b)    Generator sets independent of the normal supply

c)    Solar Photovoltaic array

d)    Storage batteries

6.  The protective measures of placing out of reach and the use of obstacles shall only be used in installations

a)    Connected to a TT system

b)    Where access is restricted to skilled or instructed persons

c)    Covered by RCD protection

d)    Utilizing reduced low voltage

7. The maximum disconnection time for a 30A final circuit protected by a BS3036 rewireable fuse, supplied from a TN-C-S 230V system is

a)    0.8 seconds

b)    0.2 seconds

c)    0.4 seconds

d)    5 seconds



8. The maximum disconnection time for a 20A distribution circuit protected by a BS EN 60898 mcb, supplied from a TN-C-S 230V system is

a)    0.8 seconds

b)    0.2 seconds

c)    0.4 seconds

d)    5 seconds



9.  The maximum tabulated earth loop impedance for a 32A final circuit protected by a BS88-2 fuse, supplied from a TN-S 230V system is


a)    0.99 Ω

b)    0.91 Ω

c)    1.70 Ω

d)    1.37 Ω

10.  The maximum tabulated earth loop impedance for a 40A final circuit supplying fixed equipment, protected by a BS88-2 fuse, supplied from a TN-C-S 230V system is


a)    0.55 Ω

b)    1.09 Ω

c)    1.30 Ω

d)    1.04 Ω

11.  In a reduced low voltage system, what is the maximum disconnection time that should be achieved?

a)    0.4 seconds

b)    1 second

c)    5 seconds

d)    40ms


12. What is the maximum tabulated earth fault loop impedance for a three-phase reduced low voltage circuit protected by a 25A type C circuit-breaker to BS EN 60898

a)    0.21 Ω

b)    0.24 Ω

c)    0.42 Ω

d)    0.52 Ω


13. Which one of the following is recognized as additional protection?

a)    An RCD with a rated residual operating current  not exceeding 30mA

b)    A 30mA RCD operating at 150mA

c)    A 100mA RCD operating within 40ms at 500mA

d)    A 300mA RCD operating within 300ms at 300mA



14. The maximum limiting temperature for a metallic part which is intended to be touched but not hand-held is

a)    80ºC

b)    90ºC

c)    70ºC

d)    65ºC.

15. Where overload protection is afforded by a semi-enclosed BS3036 fuse, compliance with Reg. 433.1.1 is achieved if the rated current does not exceed

a)    0.725 x the current carrying capacity of the protective conductor.

b)    1.45 x the current carrying capacity of the conductor, Iz.

c)    1.45 x  the current carrying capacity of the protective conductor

d)    0.725 x the current carrying capacity of the lowest rated conductor, Iz.

16.  When calculating the effects of fault current for disconnection times up to 5 seconds, a factor, k, takes account of the resistivity, temperature coefficient and heat capacity of the conductor material. For a 16mm copper conductor insulated with 70ºC thermoplastic insulation, the value of k will be

a)    143

b)    115

c)    100

d)     86



17. To minimize electromagnetic disturbances, equipotential bonding designed as a bonding ring network shall have a minimum nominal dimension  of

a)    25 mm²

b)    8 mm round diameter

c)    25 mm x 8 mm flat cross-section

d)    10 mm²



18. The minimum distance between information technology cables and discharge, neon and mercury vapour lamps shall be

a)    100 mm

b)    50 mm

c)    600 mm

d)    130 mm


19.  A functional earthing conductor shall be identified by


a)    The letter M

b)    The number 0

c)    The colour green/yellow

d)    The colour cream



20.  A cable passing through a joist within a floor shall be


a)    Enclosed in pvc conduit

b)    Not more than 50 mm from the top of the joist

c)    Part of a SELV or PELV circuit meeting the requirements of Reg. 414.4

d)    Not more than 50 mm from the bottom of the joist

21.  A cable totally surrounded by thermal insulation for a distance of 100 mm shall have a derating factor applied of

a)    0.5

b)    0.63

c)    0.78

d)    0.88


22.  Every connection shall be accessible for inspection, testing and maintenance, except for  

a)    a compound-filled or encapsulated joint

b)    a joint made in a standard joint-box

c)    taped connector blocks in lighting circuits

d)    supply connections to SELV lighting transformers


23.  Connecting conductors between surge protection devices and the MET or protective conductor should have a cross- sectional area of not less than

a)    10 mm² copper for any Type.

b)    6 mm² copper for Type 1 SPD's.

c)    16 mm² copper for Type 2 SPD's.

d)    6 mm² copper for Type 2 SPD's.



24. The steel wire armouring of a cable having copper conductors of 10 mm² is to be used as the protective conductor. What would be the minimum tabulated cross-sectional area of the steel wire armour if it is insulated with 70ºC PVC?

a)    22.5 mm²

b)    4.43 mm²

c)    10 mm²

d)    6.5 mm²


25.  A TN-C-S system has live conductors of 70 mm² and an earthing conductor of 25 mm². The cross-sectional area of the main bonding conductor will be

a)    10 mm²

b)    16 mm²

c)    25 mm²

d)    35 mm²

26. The classification of an automatic electrical safety service supply that is available within 0.5 seconds would be


a)    Very short break

b)    Short break

c)    Normal break

d)    Medium break



27.  Electrical Installation Certificates and Minor Electrical Installation Works Certificates shall be compiled and signed or otherwise authenticated by


a)    An ECA, NICEIC or NAPIT approved electrician

b)    A qualified engineer holding City & Guilds 2391 or 2394/2395 certificates

c)    A senior testing engineer holding JIB Approved status

d)    One or more skilled persons, competent to verify the requirements have been met.


28.  The space under a bath, if accessible only with the use of a tool is

a)    Zone 0

b)    Zone 1

c)    Zone 2

d)    Outside of the zones



29. Socket outlets used in Medical IT systems, in Group 2 locations should be

a)    Metal-clad and double-pole switched

b)    Coloured blue and marked “medical equipment only”.

c)    Coloured white and marked “medical staff use only”

d)    Installed at a height of between 1 m and 1.4 m



30. When completing an Electrical Installation Condition Report, any observations should be given a code. The code C2 is allocated to indicate

a)    Conforms completely with the Regulations, but is out of date.

b)    Improvement recommended

c)    Potentially dangerous-urgent remedial action required

d)    Danger present. Risk of injury. Immediate remedial action required


   1       C       110.2 (ii)  exclusions, a general list of exclusions

   2       D       132.7  (iii) Type of wiring and method

   3       B        Definitions , Alphabetical list

   4       A        Definitions , Alphabetical list

   5       C       351.1  Safety service sources

   6       B       410.3.5  Protection against shock-general

   7       C       Table 41.1 Maximum disconnection times

   8       D       411.3.2.3   Automatic disconnection

   9       A       Table 41.2 Maximum earth loop impedances-0.4s

 10       C       Table 41.4 Maximum earth loop impedances- 5s

 11       C       411.8.3      Reduced low voltage systems

 12       B       Table 41.6 Maximum earth loop impedance

 13       A       415.1.1      Additional protection – RCDs

 14       C       Table 42.1 Protection against burns

 15       D       433.1.101  Protection against overload current

 16       B       Table 43.1 Protection against fault current

 17       B       444.5.3      Measures against EMIs-bonding rings

 18       D       444.6.2      Measures against EMIs- segregation

 19       D       Table 51    Identification of conductors

 20       C       522.6.201 (ii) Select & erect wiring systems – impact AG (refers to Reg 522.6.204 (v).

 21       C       Table 52.2  Current carrying capacity- thermal ins.

 22       A        526.3        Connections

 23       D        534.4.10   Connecting conductors of SPD's

 24       A        Table 54.7 CSA of protective conductors (115/51 x 10 = 22.55)

 25       C        Table 54.8 CSA of main bonding – PME (for a 70mm² PEN conductor)

 26       B         560.4.1     Safety services – classification

 27       D         644.5        Certification for Initial Verification

 28       D        701.32.3    Bathrooms – zoning

 29       B        710.553.1  Medical locations – socket outlets

 30       C        App.6  p.474  Model forms for certification

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