Unit 303 Sample Questions

[Sparky Ninja]

UNIT 303 SAMPLE QUESTIONS

1. State two faults which may be found for each of the following.
a) Luminaires (2 marks)
b) Flexible cables / cords (2 marks)
c) Wiring (2 marks)


2. Identify the three basic principles of undertaking fault diagnosis (6 marks)


3. Identify two items of equipment which would be connected to each of the following voltages.
a) 400v (2 marks)
b) 230v (2 marks)
c) ELV (2 marks)


4. A ring final circuit develops a fault after shopfitting work has been carried out. The consumer has tried resetting the circuit breaker but it continually trips. Identify;
a) the test to be carried out before any part is dismantled (2 marks)
b) a test that could be used to determine the nature of the fault (2 marks)
c) a method of determining the actual position of the fault (2 marks)


5. Draw a simple flow chart to show the isolation procedure for a single circuit in a 6 way distribution board. (6 marks)


6. Your company is called to a factory which is involved in a 24/7 production process. The equipment identified as faulty was installed by the equipment manufacturer nine months ago.

Identify three factors which could influence your decision to rectify or replace the equipment. (6 marks)


7. Identify three situations where the working environment may effect rectification of faulty equipment. (6 marks)


8. a) Apart from aesthetic reasons (appearance) state two reasons for making good the fabric of a building after repair work has been carried out. (4 marks)
b) Where a cable enclosure is made of non-flame propagating material, what is the largest cross sectional area of a hole that need not be sealed. (2 marks)


9. State the relevant test to be carried out for each of the following.
a) To check for nuisance tripping in residual current device. (2 marks)
b) Where metal conduit is used as a cpc. (2 marks)
c) To confirm the suitability of the protective device at the origin to handle fault current. (2 marks)


10. Identify,
a) in the correct sequence, as identified in the IEE On-Site Guide, the first three dead tests that should be carried out on a ring final circuit protected by an rcd. (4 marks)
b) two live tests to be carried out on the circuit. (2 marks)


11. A ring final circuit is suspected to be faulty. Resistance measurements taken from the distribution board produces the following values:

r1 = 0.6 ohms
rN = 0.6 ohms
r2 = 1.0 ohms

Measurements at each of the 10 sockets supplied by the ring indicate the following.

Sockets 1-7
R1&RN = 0.3 ohms / R1&R2 = 0.4 ohms

Socket 8
R1&RN = 0.3 ohms / R1&R2 = >999 ohms

Socket 9
R1&RN = 0.6 ohms / R1&R2 = 0.6 ohms

Socket 10
R1&RN = 0.6 ohms / R1&R2 = 0.8 ohms


State,
a) the expected values of R1&RN and R1&R2 at each socket outlet (2 marks)
b) a possible reason for the >999 ohms reading on socket 8 (2 marks)
c) a possible reason for the higher values on sockets 9 and 10 (2 marks)


12. An earth loop impedance test on a socket supplied via a type 'C' circuit breaker measures a value which is just over the permitted value. Assuming that the circuit and wiring are sound,

State two methods which may be used to overcome this problem (6 marks)


13. List three relevant sources of information that may be used when re-comissioning an installation after repair. (6 marks)


14. Describe how to carry out a continuity test on an earthing conductor which may have been damaged during building work. (6 marks)


15. After carrying out fault finding and repair on an electrical installation, state
a) three waste materials which may require removal from site (3 marks)
b) how old discharge lamps must be handled and disposed off (3 marks)


16. State,
a) the documentation to be completed following the re-commisioning of an installation (3 marks)
b) to whom the paperwork is delivered (2 marks)
c) who decides the date of the next test. (1 mark)




ANSWERS TO COME SOON..

 

[trinityy3k]

Hi

Sat this on exam the other day and this was the exact exam paper but with the questions in a different order.

Nice one Widdler

 

[apollo1979]

Do you have the answers widdler?

Cheers
Rob

 

[Sparky Ninja]

UNIT 303 SAMPLE QUESTIONS

1. State two faults which may be found for each of the following.
a) Luminaires (2 marks)
b) Flexible cables / cords (2 marks)
c) Wiring (2 marks)

Any from;
a) broken terminal, broken/burnt lampholder, exposed conductors, faulty component etc. Broken lamp NOT acceptible.
b) pulled out conductor, missing or broken cord grip, mechanical damage to sheathing etc.
c) chewed cables, cable damaged by fixings, pinched cables, burnt cables etc.

2. Identify the three basic principles of undertaking fault diagnosis (6 marks)

a) knowledge and understanding of equipment,
b) use of personal and others experience,
c) use of logical approach.

3. Identify two items of equipment which would be connected to each of the following voltages.
a) 400v (2 marks)
b) 230v (2 marks)
c) ELV (2 marks)

a) Motors, water heating, commercial cookers, welding etc or suitable alternative,
b) Sockets, lighting, Domestic cooking, small power etc,
c) Alarm systems, elv lighting, bell and call systems etc.

4. A ring final circuit develops a fault after shopfitting work has been carried out. The consumer has tried resetting the circuit breaker but it continually trips. Identify;
a) the test to be carried out before any part is dismantled (2 marks)
b) a test that could be used to determine the nature of the fault (2 marks)
c) a method of determining the actual position of the fault (2 marks)

a) test to make sure all the circuits to be worked on are dead,
b) Insulation resistance test between conductors,
c) Half split test method or suitable alternative.

5. Draw a simple flow chart to show the isolation procedure for a single circuit in a 6 way distribution board. (6 marks)

Identify Circuit > open and lock off > Circuit proved dead > Voltage indicator function confirmed > Warning notices posted > Single key kept on person.


6. Your company is called to a factory which is involved in a 24/7 production process. The equipment identified as faulty was installed by the equipment manufacturer nine months ago.

Identify three factors which could influence your decision to rectify or replace the equipment. (6 marks)

a) Machine/equipment still under warranty
b) Loss of production
c) Access to equipment in factory with continual working or suitable alternatives.

7. Identify three situations where the working environment may effect rectification of faulty equipment. (6 marks)

a) equipment still hot from being used (ovens/kilns)
b) equipment still waterlogged or submerged (pumps etc)
c) weather, high winds, rain, snow etc preventing safe access to out of doors equipment or suitable alternatives.


8. a) Apart from aesthetic reasons (appearance) state two reasons for making good the fabric of a building after repair work has been carried out. (4 marks)
b) Where a cable enclosure is made of non-flame propagating material, what is the largest cross sectional area of a hole that need not be sealed. (2 marks)

a) to prevent the spread of fire and smoke, to prevent noise penetration, to maintain building compartments etc. Any two.
b) 710mm squared (regulation 527.2.6).

9. State the relevant test to be carried out for each of the following.
a) To check for nuisance tripping in residual current device. (2 marks)
b) Where metal conduit is used as a cpc. (2 marks)
c) To confirm the suitability of the protective device at the origin to handle fault current. (2 marks)

a) 0.5 x I delta n (half rated current test) of RCD on both half cycles or ramp test,
b) R2 test using low resistance ohmmeter,
c) Prospective short circuit current test.

10. Identify,
a) in the correct sequence, as identified in the IEE On-Site Guide, the first three dead tests that should be carried out on a ring final circuit protected by an rcd. (4 marks)
b) two live tests to be carried out on the circuit. (2 marks)

a) Ring final circuit continuity, Insulation resistance, Polarity - CORRECT order,
b) Earth loop impedance and RCD. ( Do NOT include live polarity, strictly speaking it is a check, not a test).

11. A ring final circuit is suspected to be faulty. Resistance measurements taken from the distribution board produces the following values:

r1 = 0.6 ohms
rN = 0.6 ohms
r2 = 1.0 ohms

Measurements at each of the 10 sockets supplied by the ring indicate the following.

Sockets 1-7
R1&RN = 0.3 ohms / R1&R2 = 0.4 ohms

Socket 8
R1&RN = 0.3 ohms / R1&R2 = >999 ohms

Socket 9
R1&RN = 0.6 ohms / R1&R2 = 0.6 ohms

Socket 10
R1&RN = 0.6 ohms / R1&R2 = 0.8 ohms


State,
a) the expected values of R1&RN and R1&R2 at each socket outlet (2 marks)
b) a possible reason for the >999 ohms reading on socket 8 (2 marks)
c) a possible reason for the higher values on sockets 9 and 10 (2 marks)

a)
(i) (0.6+0.6)/4 = 0.3 ohms
(ii) (0.6+1.0)/4 = 0.4 ohms
b) cpc disconnected or cross polarity at socket
c) sockets are both connected as spurs

12. An earth loop impedance test on a socket supplied via a type 'C' circuit breaker measures a value which is just over the permitted value. Assuming that the circuit and wiring are sound,

State two methods which may be used to overcome this problem (6 marks)

a) Change circuit breaker to type B. (1 mark only if candidate states 'change breaker')
b) Fit an RCD or RCBO to circuit, or suitable alternative.

13. List three relevant sources of information that may be used when re-comissioning an installation after repair. (6 marks)

Any three from;
a) IEE Wiring Regulations
b) Contract specifications
c) Distribution/wiring diagrams
d) Manufacturers instructions
Relevant statutory legislation.

14. Describe how to carry out a continuity test on an earthing conductor which may have been damaged during building work. (6 marks)

a) isolate supply
b) check low resistance ohmmeter for correct operation
c) disconnect main earthing conductor at the Main Earthing Terminal
d) use method 2 from OSG to test continuity (long lead method)
e) Verify continuity of conductor (or not)
f) Reinstate conductor and connections.

Or suitable alternative.

15. After carrying out fault finding and repair on an electrical installation, state
a) three waste materials which may require removal from site (3 marks)
b) how old discharge lamps must be handled and disposed off (3 marks)

a) any from cardboard, paper, plastic packaging, expended polystyrene, brick rubble etc/ or alternatives.
b) repackaged in boxes and transported to a licensed company for disposal as hazardous waste

Or suitable alternative.


16. State,
a) the documentation to be completed following the re-commisioning of an installation (3 marks)
b) to whom the paperwork is delivered (2 marks)
c) who decides the date of the next test. (1 mark)

a) Periodic Inspection Report, Schedule of Inspections, Schedule of Test Results,
b) The person ordering the test,
c) The person carrying out the inspection and test.



ANSWERS TO COME SOON..

answers done.

 

[Iona222]

where's the answers?

 

[DPG]

where's the answers?

Thread is 10 years old.

 

[i=p/u]

I remember wilder always posting stuff for the people out there learning. Or he was teaching himself

 

[Eddy Currents]

where's the answers?

The answers are there in post #4

 

[Sparky Ninja]

I remember wilder always posting stuff for the people out there learning. Or he was teaching himself

still up to my old habits. Just under a different name.

 

[i=p/u]

Hope your doing well, you make a million yet??

 

[Sparky Ninja]

Hope your doing well, you make a million yet??

You gotta be jokin mate. I keep giving this stuff away for free ?

 

[Iona222]

Hi

Sat this on exam the other day and this was the exact exam paper but with the questions in a different order.

Nice one Widdler

I sat the exam Sunday, failed by 1 question.