Deck 6: Completion of Test Certificates

Question 1

During an initial verification three conditions must be verified, one of these conditions as stated in BS7671 is:

A) All working correctly
B) All circuits have been inspected
C) All electrical equipment has been installed in compliance with section 511
D) Correctly selected and erected in accordance with the building regulations

Answer 1

C

Question 2

A non statutory document which may be referred to during the inspection of an electrical installation is:

A) ESQCR 2002
B) On Site Guide
C) HASWA 1974
D) EAWR 1989

Answer 2

B

Question 3

A statutory document which may be referred to during initial verification is

A) BS 7671
B) GN 3
C) GS 38
D) EAWR 1989

Answer 3

D

Question 4

The purpose of an initial verification as described in GN3 is

A) To confirm by inspection and test that the installation complies with the design and construction aspects of BS 7671
B) To confirm by inspection and test that the installation complies with the design and construction aspects of EAWR 1989
C) That it works correctly and is compliant with GN3
D) To confirm that it is complete and works correctly

Question 5

A test value which may be obtained by the use of an RCD tester would be

A) 30mA
B) 30m/Ω
C) 30s
D) 30m/s

Question 6

In sequence the first three tests carried out on a ring circuit would be

A) L-L, N-N, E-E
B) Ring final circuit test, insulation resistance test, earth fault loop impedance
C) Ring final circuit test, polarity, insulation resistance test
D) All conductors end to end, L-N cross connected, L-E cross connected

Question 7

An insulation resistance test carried out on five circuits of an electrical installation provided the following results, 50MO, 39MO, 56MO, 83MO and 26MO. Calculate the expected resistance if all of the circuits were to be measured together in parallel

A) 19MΩ
B) 87MΩ
C) 8.77MΩ
D) 8.77mΩ

Question 8

A special location which may be connected to a TN-C-S system is

A) Construction site
B) Swimming pool
C) Caravan site
D) Sauna

Question 9

The insulation resistance test voltage which may be applied to a circuit containing surge protection is

A) 230v d.c
B) 500v d.c
C) 250v d.c.
D) 1000v d.c.

Question 10

The number of tests required when carrying out a resistance test on an earth electrode which is to be used with a generator is

A) 3
B) 4
C) 6
D) 1

Question 11

State one situation within a domestic installation which would require the installation of an RCD

A) Existing circuits in a bathroom
B) Additional socket outlet installed in a bedroom
C) Fused spur installed using mini trunking
D) Existing circuits protected by BS 3036 semi enclosed fuses

Question 12

An earth electrode test is to be carried out using an earth electrode tester, if the electrode under test is to be inserted to a depth of 2.5m the minimum recommended distance for the test probe C2 is

A) 25m
B) 12.5m
C) 2.5m
D) 2500mm

Question 13

The On Site Guide states that T.T TN-S and TN-C-S systems have the following max Ze values

A) T.T. 0.8Ω. TN-S 21Ω. and TN-C-S 0.35Ω.
B) TN-C-S 0.8Ω T.T. 21Ω. and TN-S 0.35Ω.
C) T.T. 0.35Ω. TN-C-S 21Ω. TN-S 0.8Ω
D) T.T 21Ω. TN-S 0.8Ω. TN-C-S 0.35Ω

Question 14

Where BS 7671 show a protective device as having a maximum Zs value of 2.3O the maximum corrected value will be

A) 2.3Ω
B) 1.84Ω
C) 1.72Ω
D) 2.87Ω

Question 15

A BS EN 61008-1 RCD is to be installed on a farm to provide fire protection, The maximum I∆n rating for the device would be

A) 500mA
B) 100 mA
C) 300 mA
D) 30mA

Question 16

The maximum disconnection time permissible for a BS EN 61008-1 RCD used for fire protection is

A) 0.2 s
B) 300ms
C) 200ms
D) 40ms

Question 17

The maximum permitted disconnection time for a 20A radial circuit connected to a TN-S system is

A) 0.4 sec
B) 5 sec
C) 0.2 sec
D) 40ms

Question 18

A circuit is which is 30 m long ins wired in copper conductors each of which have a resistance value of 7.41mΩ/m at 20 deg C. Calculate the expected voltage drop for this circuit if a load of 16 A is connected to it

A) 3.56 volts
B) 7.11 volts
C) 4.2 volts
D) 8.54 volts

Question 19

Voltage drop can be verified using either of two methods, these are

A) Enquiry and measurement of circuit impedance
B) Measurement of circuit impedance and calculation
C) Calculation and testing
D) Use of tables and enquiry

Question 20

To comply with recommendations provided by the HSE safe isolation should be carried out using

A) A proving unit
B) An approved voltage indicator
C) A volt stick
D) A multi meter