C&G 2391 Exam Questions - With Answers

Answers:

1.
a) Polarity
b) Higher reading
c) R1+R2

2.
a) Low reading OHM meter
b) i) Spur ii) Loose connection

3.
a) To check for short connections between the two conductors
b) Wrong ends of circuits connected together. (should be connected like this: L1-N2 and L2-N1)
c) Polarity

4.
A) Satisfactory
B) Unsatisfactory: L-CPC reversed
C) Unsatisfactory: Bad connection at the Neutral conductor
D) Unsatisfactory: No connection at the CPC conductor, P-N reversed
E) Satisfactory

5.
A) L-CPC reversed
B) L-N reversed
C) N-CPC reversed

6.
a) The resistance of the CPC conductor is higher than the resistance of the Neutral conductor
b) 0.1
c) 0.13

7.
a) Low reading Ohm meter
b) R1 - resistance of the Phase conductor , R2 - resistance of the CPC conductor

8.
a) Gas - On the consumer side of the installation, within 600mm, on hard metal pipe work, or as near as possible.
Water - On the consumer side of the installation, within 600mm, on hard metal pipe work, or as near as possible.
b) Low reading Ohm meter
c) Measure the resistance of the leads and deduct it from the readings 

9.
a) All sockets and outlets
b) L-CPC
c) R1+R2

10.
a) EAWR 1989
b) Duty holder
c) Non-statutory

11.
a) i) 2mm probes  ii) Fused to max 500mA
b) Non-statutory

12.
a) BS 7671
b) EAWR 1989
c) GN 3

13.
a) i) Electrical Installation Certificate ii) Schedule of test results iii) Schedule of inspections
b) EAWR1989
c) GS 38
d) BS 7671

14.
a) Initial verification
b) Electrical Installation Certificate

15.
a) Non-statutory
b) Non-statutory
c) Statutory