Testing And Inspection Revision

Question 1

Non-statutory document that is applicable to the probesand leads of test equipment

Answer 1

Hse guidance note Gs 38

Question 2

The following tests may be carried out on a new installation: 1- polarity 2- insulation resistance 3- ring final circuit continuity 4- cpc continuity, what is the correct sequence for a new ring final circuit

Answer 2

3, 2,1- ring final circuit continuity, insulation resistance, polarity

Question 3

If the length of a cable is doubled the insulation resister will be

Answer 3

Halved

Question 4

If the length of a cable is doubled the resistance will be

Answer 4

Doubled

Question 5

When carrying out an initial verification, a check for polarity is carried out when energising the installation for the first time, why is this?

Answer 5

Correct connection of the incoming supply

Question 6

A continuity of protective conductors test is carried out using a

Answer 6

Low resistance ohmmeter

Question 7

The maximum permitted voltage drop for a low voltage lashing circuit supplied directly from the public supply is

Answer 7

3%, 3% is for lighting and 5% is for power

Question 8

An increase in conductor operating temperature will result m

Answer 8

An increase in conductor resistance

Question 9

External earth fault loop impedance Ze for an installation must be measured at

Answer 9

The origin of the installation with the earthing conductor disconnected

Question 10

The maximum tabulated earth fault loop impedance value for a 32a type c circuit breaker to Bsen 60898 is 0.68, the maximum measured earth fault loop impedance permitted for a circuit protected by this device is

Answer 10

0.54 because 0.68 ÷ 100 = 0.0068 then x 80 =0.54 - the rue of thumb

Question 11

Following the installation and completion of a new circuit the following should be issued

Answer 11

Eic, electrical installation certificate

Question 12

Rcd testers display the test result in what

Answer 12

Milliseconds

Question 13

An approved voltage indicator should have test leads fused at what

Answer 13

0.5a

Question 14

A 30 ma Rcd utilised for additional protection when rested of 150 ma should operate within

Answer 14

40ms

Question 15

The top surface of switch gear giving ip 4x protection would be checked with wire of csa

Answer 15

1 mm

Question 16

The minimum acceptable value for an installation resistance test on a selv circuit is

Answer 16

1M ohm

Question 17

A 32a 60898 circuit breaker protects a ring final circuit the Max result allowing the 0.8 factor should be

Answer 17

1.09 ohms

Question 18

The open circuit resistance values on a ring final circuit were r1= 0.6, rn= 0.6 and r2= 0.96 what would be the r1 + r2 value expected for the circuit

Answer 18

0.39 ohms, because 0.6+ 0.96 ÷4= 0.39

Question 19

A test on 6 circuits reveals a test result of 1.6Mohms, what as the inspector and tester would you do

Answer 19

Consider dividing the installation and retest

Question 20

A circuit under test has a link between line and cpc at one end with a low resistance ohm meter connected between the same conductors at the other end, the test could indicate

Answer 20

Continuity and r1+ r2 values