18th Edition Mock Exam

This 18th Edition Mock Exam contains 60 Questions. You have 120 minutes (2 hours) to complete the assessment. You must get a score of 36/60 to pass. Good luck!

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Correct Answer: D SELV
Explanation: Page 256 - 704.410.3.10 Note 2: - The part 7 contents page (P239) indicates section 704 refers to 'Construction and demolition site installations' you will find section 704 starts on page 256 you need to browse the section looking for the key 'protection against electric shock' you will find this in 704.410.3.10 Note 2: the SELV system is the 'strongly preferred' method for portable handlamps in confined or damp locations
Correct Answer: D Core 8
Explanation: Page 313 - Table A721 - Annex A721 - Linked with A721.55.2.6 - The part 7 contents page (P239) indicates section 721 refers to 'Electrical Installations in Caravans and Motor Caravans' you will find section 721 on page 306, you must skim through the section to Annex A721 to find the answer. Try to remember, you may find the answer to many motor homes or motor caravan accessories questions in Table A721. Looking down the Function column for 'Reversing light' and cross-reference with the Core number column you will find the reversing light should be connected via core 8
Correct Answer: B 230 V
Explanation: Page 330 - 740.313.1.1 - The part 7 contents page (P239) indicates section 740 refers to 'Temporary Electrical Installations for Structures' no mention of 'Circuses' this term has been removed from the Part 7 contents page. you will find section 740 on page 330; you need to look for some reference to 'Voltage' and in 740.313.1.1 you will find that the nominal voltage shall not exceed 230 volts a.c. - 400 volts a.c. would be for a 3-phase system, 240V a.c. (nominal) was changed a long time ago
Correct Answer: D 27 m
Explanation: Page 310 - 721.55.2.6 (ii) -The Part 7 contents page (P239) indicates section 721 refers to 'Electrical Installations in Caravans and Motor Caravans' The 'key' to answering this question is the question did 'NOT' state the caravan was on a caravan site, if it had then we would have had to refer to section 708 'Caravan and Camping Parks' you will find section 721 on page 306. The answer is under the section heading 'Accessories' and in 721.55.2.6 (ii) you will find a flexible cable of continuous length of 25 m may be used, plus an allowance of +/- 2m, allowing a maximum length of 25 m + 2 m = 27 m
Correct Answer: C 2.25 metres
Explanation: Page 240 - 701.32.4 (i) - The part 7 contents page (P239) indicates section 701 refers to 'Locations containing a bath or shower' you will find section 701 on page 240, skimming the page looking for 'Zone 2' you will find the answer in 701.32.4 (i)
Correct Answer: A 0.1 second
Explanation: Page 364 - Fig 3A1 - Appendix 3 - The Appendices contents page (P339) indicates Appendix 3 contains details of 'Time/Current characteristics of overcurrent protective devices' you will find Appendix 3 starts on page 362. At the top of page 362 you can see that the values for a BS 88-3 fuse will be in Fig 3A1 (P364). With these types of questions first check out the box in the top right-hand corner of the page, if you are in luck the answer will be here. We just need to cross-reference the fuse rating row 45 A with the overcurrent value 550 A and read the disconnection value at the top of the 550 A column, you can see the disconnection time will be within 0.1 seconds
A BS 5655
B BS 67
C BS EN 50438
D BS EN 81
Correct Answer: B BS 67
Explanation: Page 340 - Appendix 1 - The Appendices contents page (P339) indicates Appendix 1 contains details of 'British Standards' you will find Appendix 1 starts on page 340. to find the answer to these British Standard type questions, it is just a matter of browsing through the standards until you find the correct answer. You will find BS 67 is the first BS standard in the BS table
A The department for innovation and skills
B The health and safety executive
C The home department
D The local authority organisation
Correct Answer: B The health and safety executive
Explanation: Page 359 - The Appendix contents page (P339) indicates Appendix 2 contains details of 'Statutory regulations and associated memoranda' this does not provide much help if you don't know what is covered by this title. Page 359 lists 'Statutory regulations and associated memoranda' you can see that 'Distributors Installations' come under the direction of the Health and Safety Executive
Correct Answer: B 21 amps
Explanation: Page 390 - Table 4A2 and Page 409 - Table 4D5 The Appendix contents page (P339) indicates Appendix 4 contains details of 'Current-carrying capacity of cables' you will find

Appendix 4 starts on page 374

Tip: To answer this question you need to know we first use Table 4A2 to determine the installation method, this is shown on page 390. you will find that for an installation with flat T&E cable clipped direct to a wooden joist, above a ceiling with thermal insulation not exceeding 100 mm thick the installation method is 100.

On the right-hand end of this row, you will find you must use Table 4D5 to obtain the cable current carrying capacity, you will find Table 4D5 on page 409

In Table 4D5 we cross-reference 2.5 mm² cables with installation method 100 (column 2) and you will find the answer is a current-carrying capacity of 21 amps
Correct Answer: B 0.447
Explanation: Page 375 - Appendix 4 - Section 2.3.3.1 - The Appendices contents page (P339) indicates Appendix 4 refers to 'Current-carrying capacity and voltage drop for cables' and starts on page 374; this is an error as the Appendix 4 contents page actually starts on page 373. You need to remember anything to do with cable grouping will affect the current carrying capacity of the cable. Turning to (P373) we browse looking for anything to do with groups of cables. In 2.3.3.1 (P375) you will find the cable grouping formula shown below. Guide: we apply the formula as follows:



Where:

Cg = the group factor

n = the number of circuits

In this question, the number of circuits is five

So, the formula becomes



To enter this into a Casio FX calculator place the calculator in MATH mode by pressing SHIFT MODE 1 1

The MATH symbol will now be visible in the status line

Once in Math mode type in the following keys



The answer will appear as a decimal number 0.447
A A contactor
B A device with semiconductors
C A fuse
D An RCD
Correct Answer: B A device with semiconductors
Explanation: Page 181 - Table 537.4 - Linked with 537.2.2 (P182) - The part 5 contents page (P124) indicates section 537 refers to 'Isolation and switching' so we will start here. You need to remember Table 537.4 on page 181 - This table lists devices that can be used for Isolation, Emergency, and Functional switching. If we look down the table, on the 3rd row from the bottom, you will see in the Device column 'Device with semiconductors' and in the Isolation column the indication is 'No' Additionally, in the index (P540) 'Isolator Semiconductor devices not to be used as' refers to 537.2.2 Note the small symbols or numbers at the end of the table (P182) if present on a device indicate what type of switching or isolation may be used, e.g. the number (3) on a device indicates it is suitable for on-load isolation i.e. disconnection whilst carrying a load current
A The highest and lowest local ambient temperature
B The maximum ambient temperature
C The maximum and minimum conductor temperature
D The maximum conductor temperature
Correct Answer: A The highest and lowest local ambient temperature
Explanation: Page 138 - 522.1.1 - The part 5 contents page (P124) indicates section 522 refers to the 'Selection and erection of wiring systems in relation to external influences. You need to realise that anything that can damage a wiring system is considered an 'External Influence'. you will find section 522 on page 138 and in 522.1.1 the answer
A Earth bonding SPD's
B Equipotential bonding SPD's
C Exposed conductive SPD's
D Extraneous conductive SPD's
Correct Answer: B Equipotential bonding SPD's
Explanation: Page 161 - 534.4.1.1 Note - The part 5 contents page (P124) indicates section 534 refers to 'Devices for protection against overvoltage' you need to remember SPD's are devices for protection against overvoltage. you will find 534.4.1.1 on page 161 the answer is the Note
Correct Answer: D BS EN 60073 and BS EN 60447
Explanation: Page 129 - 514.1.1 - The part 5 contents page (P124) indicates section 514 refers to 'Identification and notices' - Turning to this section, top of page 129, you will find 514.1.1 and the answer
A Advertising signs
B Festoon lighting that is temporary
C Phone kiosks
D Road lighting
Correct Answer: B Festoon lighting that is temporary
Explanation: Page 218 to page 219 - 559.1 (iii) - The part 5 contents page (P125) indicates section 559 refers to 'Luminaires and lighting installations' - you will find section 559 on page 218, in 559.1 (iii) (P219) you will find the answer. The other types of lighting listed can be found on page 293 section 714 'Outdoor lighting installations'
Correct Answer: D 90℃
Explanation: Page 142 - Table 52.1 - This can be a difficult answer to find, if we don't know the 'key'. The key is to remember questions like this are really referring to 'Current carrying capacities of cables' the part 5 contents page (P124) indicates section 523 refers to 'Current carrying capacities of cables' But, if you didn't know this, then the following directions will help you will find the answer. The index under 'Cables - Current carrying capacity' (P528) directs you to section 523 and Table 52.1 is shown immediately below 523.1

Tip: Try to remember questions like this will be in section 523 'Current carrying capacities of cables'
A Auxiliary circuits
B Generator control circuits
C IT systems
D Safety services circuits
Correct Answer: A Auxiliary circuits
Explanation: Page 214 - Fig 55.1, Fig 55.2, Fig 55.3 - The part 5 contents page (P125) indicates section 557 refers to 'Auxiliary circuits', but this is no use to you if you didn't know these images were auxiliary circuits. you will find section 557 on page 213 - the images are shown on page 214 - Fig 55.1, 55.2, 55.3 provides the answer
Correct Answer: D
Explanation: Page 145 - 146 - 526.3 (vi) - The part 5 contents page (P124) indicates section 526 refers to 'Electrical connections' so start here. Page 145 - 146 - 526.3 (vi) provides the answer. Answer d) is correct, equipment where it is not possible to obtain access for, inspection testing and maintenance so long as it complies with the requirements of BS 5733 may be marked with the symbol shown in
Correct Answer: C 35 mm²
Explanation: Page 202 and page 203 - 544.1.1 and Table 54.8 - The part 5 contents page (P124) indicates section 544 refers to 'Protective bonding conductors' Page 202 displays 544.1.1 where we are advised in the second paragraph 'Where PME conditions apply' the main protective bonding conductor shall be selected in accordance with the PEN conductor of the supply and Table 54.8 - you can see in Table 54.8 that for a PEN conductor over 95 mm² up to 150 mm², the main protective bonding conductor must be 35 mm²
A Blue only
B Green only
C Green-and-Yellow only
D Green-and-Yellow throughout its length with blue markings at the terminations
Correct Answer: D Green-and-Yellow throughout its length with blue markings at the terminations
Explanation: Page 129 - 514.4.3 (i) - The part 5 contents page (P124) indicates section 514 refers to 'Identification and notices' You will find the answer on page 129 - 514.4.3 (i)
Correct Answer: C Normal break
Explanation: Page 224 - 560.4.1 (d) - The Part 5 contents page (P125) indicates section 560.4 refers to 'Safety service classifications' turning to this page (P224) you will find 560.4.1 (d) and the answer; anything to do with no-break, very short break, short, normal, medium or long break will probably be in this section - try to remember this
A High severity vibration
B Low severity vibration
C Medium severity vibration
D Very low severity vibration
Correct Answer: A High severity vibration
Explanation: Page 140 - 522.7.1 - The part 5 contents page (P124) indicates section 522 refers to the 'Selection and erection of wiring systems in relation to external influences' You need to realise that anything that can damage a wiring system is considered an 'External Influence'. you will find section 522 on page 138; a quick skim through the section to page (P140) reveals 522.7 'Vibration (AH) and in 522.7.1 you will find the answer. We could also have used Appendix 5 (P446) here you will find AH3 listed as 'High Vibration' Try to remember the answer to anything to do with external influence codes beginning with the letter's 'A', 'B', or 'C' in the part 5 section of the exam will probably be in section 522
Correct Answer: D 50 mm²
Explanation: Page 198 - Table 54.7 - Linked with - 543.1.4 Guide: We are informed the line conductor has a c.s.a of 95 mm² this means you must use the row S > 35 mm². The middle column is for when the line conductor and protective conductor are made of the same material, in this question both are made of copper so we use the formula S÷2. Therefore: 95 mm² ÷ 2 = 47.5 mm² Note: 47.5 mm² is not a standard size so you must select the next largest c.s.a size, which is 50 mm²
Correct Answer: C Replace the ferrous material with non-ferrous at the point of entry
Explanation: Page 136 - 521.5.1 - The part 5 contents page (P124) is no good in trying to find an answer to this question, so try the chapter 52 contents page (P135) here you will find section 521.5.1 refers to 'Ferromagnetic enclosures' you will find this section on page 136; the second paragraph states 'Where such conductors (as shown in the image below) enter a ferrous enclosure, they shall be arranged such that the conductors are only collectively surrounded by ferromagnetic material. (this would mean bunched in a group)

Tip: When you have to run single-core cables that are expected to draw some appreciable amount of electric current through a metal ferrous enclosure, you must be aware that the magnetic field that will be created by the a.c. current in the conductors will induce eddy currents into the ferrous material of the enclosure, shown in the image below.



These eddy currents, which are electric currents, draw their power from the electric current in the conductors, this means less electric current is available for the load the conductors are supposed to be supplying. Additionally, the eddy currents will cause the ferrous enclosure to start to get warm, and in time possibly hot, so some means must be found to eliminate the eddy currents.

Rubber or plastic grommets are electric insulators not magnetic field insulators. No insulation material exists that will block a magnetic field. A magnetic field will go straight through steel, lead, rock, diamond, anything. Are you a bit sceptical about that? Then consider the planet Earth, the Earth's core produces the Earth's magnetic field, this field starts from the centre of the planet, travelling through thousands of miles of magma and solid rock, extending 370,000 miles into space. The only material that can shield a magnetic field is Mu-Metal but even this can't total block a magnetic field.

The solution is to cut away the ferrous material where the cables enter the enclosure, and replace it with something that is 'Not Ferrous' such as Brass, or Aluminium. These materials are conductors, and as such any eddy currents created in them will have virtual no resistance to the flow of electric current, no resistance means no opposition to the flow of eddy currents, hence no heating effect, and no power loss. If a steel enclosure was used, the eddy currents would flow in the steel which is a poor conductor, containing an appreciable amount of resistance, it is this resistance to the flow of eddy currents that causes a ferrous metal enclosure to heat up. So just cut out a portion of the steel enclosure, braze in an aluminium or brass plate, and your problem is solved.
A A minor works certificate
B A new installation certificate
C A periodic inspection certificate
D An electrical installation certificate
Correct Answer: D An electrical installation certificate
Explanation: Page 236 - 644.1 - The part 6 contents page (P228) indicates section 644 refers to 'Certification for Initial Verification' upon turning to this section (P236) you will find regulation 644.1 and the answer. An Electrical Installation Certificate is required
Correct Answer: A 1000 V
Explanation: Page 232 - Table 64 - Linked with 643.3.2 - The part 6 contents page (P228) indicates section 643.3 refers to 'Insulation resistance'. Turning to page (P232) you will find Table 64 which indicates for circuits with a nominal voltage above 500 volts the Insulation Resistance test voltage must be 1000 volts
A Designer
B Inspector
C Person ordering the works
D Skilled competent persons
Correct Answer: D Skilled competent persons
Explanation: Page 236 - 644.5 - The part 6 contents page (P228) indicates section 644 refers to 'Certification for Initial Verification' you will find section 644 on page 236, then it is simply a matter of browsing down the page for the answer, which you will find in 644.5. 644.5 states that Electrical Installation Certificates, and Minor Electrical Installation Works Certificates shall be signed by skilled persons, competent to verify that the requirements of this Standard have been met
A By asking the manufacturer
B By calculation
C By enquiry
D By measurement
Correct Answer: D By measurement
Explanation: Page 233 - 643.4.1 - The Part 6 contents page (P228) indicates section 643.4 refers to 'Protection by SELV' you will find 643.4 on page 232 a quick browse of the section reveals 643.4.1 and are informed the separation of live parts from other circuits and earth shall be verified by measurement using an insulation resistance test
Correct Answer: A 100 mA
Explanation: Page 258 - 705.411.1 (ii) - The part 7 contents page (P239) indicates section 705 refers to 'Agricultural and horticultural premises' you will find section 705 on page 258, a quick skim down the page reveals the answer - 705.411.1 (ii) states that in final circuits supplying socket-outlets exceeding 32 amps an RCD not exceeding 100 mA may be used
Correct Answer: A Outside the Zones
Explanation: Page 240 - 701.32.3 last paragraph - The part 7 contents page (P239) indicates section 701 refers to 'Locations containing a bath or shower' Section 701 starts on page 240, a quick browse down the page reveals 701.32.3 and the answer. This is one question you should really know by heart. This question has appeared, with regular frequency over the years, since it covers both baths and showers in commercial and domestic premises
Correct Answer: D IPX4
Explanation: Page 266 - 708.512.1.1 - The part 7 contents page (P239) indicates chapter 708 refers to 'Electrical installations in caravan and camping parks'; 708 starts on page 265; the answer is in 708.512.1.1 which states equipment shall be selected to IPX4 in order to protect against water splashes (AD4)
Correct Answer: A 10.00 m
Explanation: Page 245 - 702.32 (ii) The part 7 contents page (P239) indicates section 702 refers to 'Swimming pools and other basins' you will find section 702 on page 245, in 702.32 (ii) you will find zone 1 is limited by a horizontal plane 2.5 metres above the surface expected to be occupied by persons. If the diving board is 7.5 m from the floor, we add 2.5 m and obtain a height of 10 metres, which is the height zone 1 extends to
A Circuits intended to supply pleasure crafts
B Equipment on board ships
C Supply to houseboats supplied directly from the public supply
D The internal electrical circuits of pleasure craft or houseboats
Correct Answer: A Circuits intended to supply pleasure crafts
Explanation: Page 270 - 709.1 Scope - The part 7 contents page (P239) indicates section 709 refers to 'Marinas and similar locations' Section 709 starts on page 270, and immediately you will find the answer in 709.1 Scope; the requirements of section 709 are applicable to circuits intended to supply pleasure craft or houseboats. Answer 'equipment of board ships' is in the exclusions list for BS 7671 on page 16
A Availability of people to carry out the work
B Frequency and quality of maintenance
C Protective measures for safety do not diminish
D Repairs can be readily and safely carried out
Correct Answer: A Availability of people to carry out the work
Explanation: Page 51 - 341.1 - If you didn't know it BS 7671 refers to 'Maintenance' as 'Maintainability 'The part 3 contents page (P44) indicates 'Maintainability' is referred to in chapter 34 a quick browse of this chapter (P51) reveals 341.1 in the regulation, you can see there is no mention of availability of people to carry out work. Whilst the availability of people to do the work is a good thing, it is not a specific requirement
A Single-phase 3-wire
B Three-phase 3-wire delta
C Three-phase 3-wire star
D Two-phase 3-wire phase angle
Correct Answer: C Three-phase 3-wire star
Explanation: Page 46 - Fig 3.4 - 312.1.1 (starts on P45) - As soon as you see any of the diagrams from page 45 - 47 of the reg's you should learn to recognise they come from the beginning of Part 3
A Assessment for its continuity of service
B Environmental influences in the region
C External influences to which its exposed
D Purpose for which the installation is intended
Correct Answer: B Environmental influences in the region
Explanation: Page 45 - 301.1 - The part 3 contents page (P44) indicates chapter 30 refers to 'Assessment of General Characteristics' -Environmental influences in the region is not listed here- Try to remember when attempting Part 3 questions, any question that refers to an assessment of the general characteristics the answer will probably be found in section 301.1
A A short-circuit of minimum current shall not occur
B Harmonic currents shall not occur
C Long duration is unlikely to occur
D Short duration is unlikely to occur
Correct Answer: C Long duration is unlikely to occur
Explanation: Page 89 - 433.1 - The 'key' to this question is the word 'coordination' The part 4 contents page (P53-54) provides no direction to this answer, quickly browsing the chapter contents pages. Chapter 41 (P55) no luck, Chapter 42 contents page (P79), nothing, so try the Chapter 43 contents page (P86). Here you can see 433.1 refers to 'Co-ordination between conductor and overload protective device' a quick browse to this section (P89) reveals the answer e.g. 'Every circuit shall be designed so that a small overload of long duration is unlikely to occur'
A Cause a dangerous overload current
B Cause a fire
C Cause a short-circuit of conductors
D Cause the cable to melt
Correct Answer: B Cause a fire
Explanation: Page 81 - 422.1.2 - The part 4 contents page (P53) indicates section 422 refers to 'Precautions where particular risks of fire exist'
Correct Answer: C 0.35 Ω
Explanation: Page 62 - Table 41.3 - The part 4 contents page (P53) indicates section 411 refers to 'Protective Measures: Automatic Disconnection of Supply' in this section you will find the fuse/MCB tables. Table 41.3 (P62) relates to 0.4 and 5 second disconnection times. The answer is in the Type D section, below the 63-amp MCB rating but in the 5-secondrow, indicating 0.35 ohms. Don't select the 0.4 second row by mistake or you will wrongly select the 0.17 ohm value - You need to know Tables 41.2, 41.3, 41.4, 41.5 contain details of maximum tabulated values of earth fault loop impedance for various fuses, MCBs and RCDs
Correct Answer: D Uf = RE x IE
Explanation: Page 98 - Table 44.1 - The part 4 contents page (P53) indicates section 442 refers to 'Protection of low voltage installations against temporary over voltages due to earth faults 'you need to remember this is pointing you to answering this type of question. Browsing to section 442 (P96) we are looking for Table 44.1, which you will find on (P98) which links with Fig 44.1 We then cross-reference the TN row with RE and RB connected (because the question informs 'the earths of the high voltage and low voltage windings of the transformer are connected' with the column under Uf, you will find the answer is the formula Uf = RE x IE
Correct Answer: C 400 ms
Explanation: Page 59 - Table 41.1 - Any question to do with disconnection times for 'final circuits' in the part 4 section of the exam will usually involve Table 41.1 and a socket outlet is a final circuit - If you didn't know that try to remember it. Table 41.1 links with 411.3.2.2, which has been revamped for the 18th Edition and is now for final circuits not exceeding 63 A for one or more socket outlets or 32 amps for supplying fixed equipment. The table lists the disconnection times. In Table 41.1, the first column refers to voltages greater than 50 V to 120 V; the second column greater than 120 V to 230 V; the third column greater than 230V to 400 V; and the fourth column for voltages over 400 V. In this question, the disconnection time is for a 230 V a.c. TN system, so we use the second system column, as this is for voltages greater than 120 V but not more than 230 V; look under the a.c. Column and cross-reference this with the TN row, and you will find the answer is 0.4 seconds (0.4 seconds is 400 ms)


A Be compatible with the requirements for starting and use of the equipment
B Have a long time delay device
C Have mandatory automatic re-closure
D Have no automatic time delay device
Correct Answer: A Be compatible with the requirements for starting and use of the equipment
Explanation: Page 120 - 445.1.4 - The part 4 contents page (P53) indicates section 445 refers to 'Protection against under voltage. Browsing to page 120 you will find section 445; browsing down the page you will find the answer 445.1.4
Correct Answer: A IP2X
Explanation: Page 74 - 416.2.1 - The part 4 contents page (P53) advises section 416 provides 'Provision for Basic Protection' turning to page (P74) you will find 416 and the answer in 416.2.1 which states live parts must be protected to at least IPXXB or IP2XIPXXXX
A Fire-resistant material
B Fire-retardant material
C Insulating material
D Non-combustible material
Correct Answer: D Non-combustible material
Explanation: Page 80 - 421.1.201(i) - The part 4 contents page (P53) indicates section 421 refers to 'Protection against fire by electrical equipment. A quick browse to the index searching for 'consumer unit' and looking for a part 4 answer reveals on (P531)'Consumer unit - for domestic premises, enclosure requirement' refers to regulation 421.1.201 and there you will find the answer
Correct Answer: C 70℃
Explanation: Page 85 - Table 42.1 - Linked to 423.1 - The part 4 contents page (P53) indicates section 423 refers to 'Protection against burns'. A quick browse to this section (P85) reveals Table 42.1 and the answer.
A Has single insulation
B Is class I
C Shall be grounded
D Shall not be grounded
Correct Answer: D Shall not be grounded
Explanation: Page 70 - 412.2.1.1 - The part 4 contents page (P53) indicates 'Double or Reinforced Insulation' is contained in section 412, so start here. Upon turning to page 70 you will observe the double insulation symbol in 412.2.1.1, if you didn't know this was the double insulation symbol, you may have had a hard time finding it. This symbol is for Class II equipment, which has double or reinforced insulation and is designed to operate 'without' a ground connection. Although it does not state in BS 7671 double insulated devices must not be connected to ground, think about it, then this is an obvious fact
Correct Answer: C 2.5 kV
Explanation: Page 105 - Table 443.2 - The part 4 contents page (P53) indicates section 443 refers to 'Protection against transient overvoltages of atmospheric origin' This is lightning. Overvoltages also known as impulse voltages are covered in section 443.6.2, with table443.2 tabulating examples of equipment and their rated impulse voltage
A On marinas where vehicle movement is prohibited
B On travelling fairgrounds to pass cables over trucks and rides
C Only on equipment that requires the use of a tool or key
D Where the equipment is controlled or supervised by skilled persons
Correct Answer: D Where the equipment is controlled or supervised by skilled persons
Explanation: Page 75 - 417.1 - The part 4 contents page (P53) indicates section 417 refers to 'Obstacles and Placing out of reach' upon opening page 75 you will see 417.1 and the answer
Correct Answer: B 76
Explanation: Page 93 - Table 43.1 - Linked to 434.5.2 (P92) - When you see a question with the above formula shown, or a question phrased about cables protected by thermoplastic, thermosetting, or mineral insulation, quoting conductor materials such as copper, or aluminium, you should be looking at regulation 434.5.2 and Table 43.1 (P92-P93)To answer this type of question we first need to select the correct insulation material e.g. 'thermoplastic, so we have four possible columns to select. Now we are informed, the insulation is 70℃ thermoplastic, so we are now restricted to using just the third and fourth data columns. Next, the conductor size quoted 50 mm² is less than 300 mm², so this means you must use the third data column. Next, the initial temperature is 70℃ and the final temperature is 160℃, so this again confirms we are using the third data column, we cross-reference this column with the conductor material e.g. 'Aluminium and you will find the k value = 76
A Where there is a risk of fire due to the manufacture of flammable materials
B Where there is a risk of harmonic currents in circuits
C Where there is a risk of isolation causing dangerous occurrences
D Where there is a risk of large overcurrents
Correct Answer: A Where there is a risk of fire due to the manufacture of flammable materials
Explanation: Page 82 - 422.3 Note 1- The part 4 contents page (P53) indicates section 422 refers to 'Precautions where particular risks of fire exist'. This is not much use to you if you didn't realise the relationship between this and the question. Remember anything to do with codes such as BE, or AA etc., will be an external influence code, so check out the appendix contents page (P339) and you see 'Classification of external influences' (P445), on (P446)you will find BE2 refers to 'Fire Risk'
A Basic protection only
B Enhanced protection
C Fault protection only
D No protection
Correct Answer: B Enhanced protection
Explanation: Page 56 - 410.3.2 Note 2 - The part 4 contents page does not provide any assistance to finding this answer, surprisingly neither does the index, I'll bet you're glad you bought this book now, if this question comes up in your exam now you know where to find the answer
Correct Answer: B Residual current
Explanation: Page 36 - Residual current - This is an example of a Definition type question where the answer is not so easy to find. The first answer option 'The Return Current' is made up, you won't find it in the Reg's. The other options do exist however
A 0.75 m
B 1.25 m
C 2.5 m
D 6 m
Correct Answer: C 2.5 m
Explanation: Page 24 - Definitions - Arms reach - Looking up arm's reach in the Definitions section (P24) or Index (P526) and you are directed to Figure 417 - Looking up figures can take some time.

Tip: you should know that (P518-P521) lists ALL figures within the book, so, from Page 24 or Page 518 you can see Figure 417 is on page 76; browsing to page 76 you will see the image shown below and the maximum arms reach distance is 2.5 m


A All live parts isolated from earth
B Combined protective and neutral functions
C Direct connection of one point to earth
D Separate protective and neutral functions
Correct Answer: A All live parts isolated from earth
Explanation: Page 47 - 312.2 Note 3: - The part 3 contents page (P44) indicates section 312.2 refers to 'Types of earthing systems' on page 47 Note 3 we are informed details of what the various codes represent. The letter 'I' indicates all parts isolated from earth
A The emergency CCTV system
B The emergency fire escape ladder system external to the building
C The emergency fire escape lighting system in the public tower lifts
D The smoke and heat extraction equipment
Correct Answer: D The smoke and heat extraction equipment
Explanation: Page 52 - 351 Note 2 - The part 3 contents page (P44) indicates 'Safety Services' are referred to in section 351 you will find in 351 Note 2: The smoke and heat extraction equipment is listed, the answer options are NOT. Whilst the emergency fire escape ladder system external to the building may initially seem to be a possible answer, as emergency escape lighting is listed in regulation 351 Note 2: public lifts are NEVER used as part of an emergency escape route. Remember all the signs you see in a public building next to the lifts 'In case of fire do NOT use the lift'
A Compatibility of its equipment
B Its general structure
C Recognised safety services
D The connections with earth
Correct Answer: D The connections with earth
Explanation: Page 45 - 301.1 - The part 3 contents page (P44) indicates section 301 refers to the 'Assessment of General Characteristics' answers. Try to remember when attempting Part 3 questions, any question that refers to 'an assessment of the general characteristics' the answer will probably be found in section 301.1
A A member of the public
B A skilled competent person
C An instructed person
D The owner of the installation
Correct Answer: B A skilled competent person
Explanation: Page 23 - 134.2.1 - You are answering a Part 1 question so look in the Part 1 Contents page, towards the lower part of page 14 you will see section 134.2 is for 'Initial Verification' a quick browse to page 23 you will find 134.2.1 'Inspection and testing shall be carried out by skilled persons competent to verify that the requirements of this standard have been met'
A 1000 V a.c.
B 1500 V a.c.
C 1500 V d.c.
D 230 V a.c.
Correct Answer: C 1500 V d.c.
Explanation: Page 15 - 110.1.2 (i) - The Part 1 contents page does not provide any help here, so try the Index, on page 555 under 'Voltage - Range covered by the Regulations' you are directed to 110.1.2 (i) and (ii)
A Increasing the earth fault loop impedance to a high value
B Limiting the duration of a current resulting from a fault, which can pass through a body, to a non-hazardous value
C Limiting the magnitude of a current resulting from a fault, which can pass through a body, to a non-hazardous time period
D Preventing a current resulting from a fault passing through the body of any livestock
Correct Answer: A Increasing the earth fault loop impedance to a high value
Explanation: Page 18 - 131.2.2 - The Part 1 contents page gives you no specific direction to the answer, but you should know 'Fault Protection' is a 'Protection against Electric Shock' this is listed in the Part 1 contents page as section 131.2. Upon turning to page 18 a quick browse provides the answer. Carefully check each answer option for what is 'True' and the answer that is left will be 'False' e.g. Not True
A Details of the client
B Particular requirements of the distributor
C The material of the main protective bonding conductors
D The name and signature of the installer
Correct Answer: B Particular requirements of the distributor
Explanation: Page 19 - 132.2 (v) - The Part 1 contents page (P14) indicates section 132.2 provides directions to 'Characteristics of available supply' within 132.2 Remember you are answering a Part 1 question NOT a Part 6, so don't be misled by what you 'think' is the answer, always check an answer ties up with an actual regulation in the part of the exam you are working on