Re-take - Useful Information for 2394 :

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I owe thisforum a hell of a lot . I’ve had more understanding of Inspection &Testing from this forum . & muchmore .
Yes at onetime I was a bit GREEN.

Dan & Jason gave me the chance to help other people & help myself in the process . So my payback is ( I am Loyal to the forum ) am not jumping ship . Electricians-Forum-Member. always 100% . No matter what hits the FAN .

Thank youDan & Jason for your Support over the Years .

 

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Younger electrician on site working with a Megger -1552 . not sure of the ropes . some assistance was in order . we’re all singingfrom the same hymn-book here . Thisforum is here to HELP-ANYBODY that needs HELP . does not mater how SMALL .

Back tobasic . ( Nulling )

Continuity- Nulling out the leads . Megger - 1552.

Switchingon . ( set at Ω ) D.C.
> 99.9kΩ - Not nulled yet . ( yourequire . Stable-reading from the Shorted-leads before you hit the -yellow-button ) a few-seconds allow .

Leadstogether 0.14Ω - the Null-symbol will not shown yet .
Push theyellow-button . once and hold a few-seconds ◄ . ( 0.00 ) the Null-symbol will remain ON . start your test .

Your ( Backlight ) press the Black-button . & it will light up .

 

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Some -facts .

p.39. GN-3. ( IR )
Insulation-résistance-testing. is a fundament-test for inspector(s) . Often on larger-construction-sites .cables will be ( Insulation-résistance-tested during various-stages ) of installationto ( Prove the integrity of the installed-cables ) it is always preferred to re-test-cable(s) andequipment for . Insulation-résistance as part of ( Initial-verification ) as well as ( During-construction )

Re-cap. p.40-GN-3 .
Simple-installation(s)that contain no-distribution-circuits should preferablybe tested as a ( Whole )

Re-cap. p.40-GN-3 .
To performthe test in a ( Complex-installation ) it may need to be ( Sub-divided into its component-parts )

Insulation-résistance.
( 2394: -point to note ) if a circuit is found tohave an ( IR ) of less than ( 2MΩ it should beinvestigated ) inGN-3.

Testing ofIndividual-circuit(s) . 2394: . you cant go wrong with this . for the sake of Exams . Safety-precautions must be taken .
If wewhere on site . each-circuit to beisolated-individually . ( Locking-OFF ) the circuit-breaker .

Only inextreme measures. Isolate the whole of the distribution-board .

Insulation-résistance. as a Whole-installation . we have Parallel -paths .
( Parallel -paths )Neutral-conductors or Circuit-protective-conductors . will be connected to acommon Neutral-bar and the Circuit-protective-conductors for all circuit(s)will be connected to ( MET ) Main-earthing-terminal .

To test Individual-circuit(s) we do not have ( Parallel -paths ) Domestic-installation .

Testing :Insulation-résistance . between allThree-conductors . Megger-1552 .settings - 250V . 500V .
Yourtesting at 500V . d.c.
Onexcising-circuits . sensitive-equipment - computers . voltage can damageequipment.

Test-betweenyour . Circuit-protective-conductor .and Line-conductor - Which is disconnected . > 500V MΩ
Test-betweenyour . Circuit-protective-conductor .and Neutral-conductor - Which is disconnected . > 500V MΩ
Test-betweenyour . Neutral-conductor . and Line-conductor - Which is disconnected . > 500V MΩ

17[SUP]th[/SUP]Edition BS-7671:2008:2011: reminds us. 500V - d.c. → → Minimum-insulation-résistance ( MΩ - 1.0MΩ )
When Idone my 2392-10 : I was taught to do ( IR ) Testing of Individual-cable(s) Line to Line . Neutral toNeutral . CPC to CPC.
&
Line to Neutral - together . plus Circuit-protective-conductor. Minimum-insulation-résistance ( MΩ - 1.0MΩ )

 

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Absence of a earthing & bonding-label . will onlybe a C3 condition on the report -
Absence of Main-protective-bonding if required by theregulations . would be a C2 . as would absence theeffective-means of earthing .

( Thereason absence of means of Earthing. Is only C2 it in not immediate dangersuch as exposed-live-part ) Unsatisfactory .

3.0 . Earthingand bonding-arrangements - p.400
- Presenceand condition of distributors-earthing-arrangement . ( C2 )
- Presenceand condition of earth-electrode-connection . ( C2 )

-Confirmation of adequate earthing-conductor-size .
-Accessibility and condition ofearthing-conductor at . Main-earthing-terminal - ( MET ) ( C2 )
-Confirmation of adequate . main-protective-bonding-conductor-size . ( C2 )

-Confirmation of accessibility of .main-protective-bonding-conductor-connections .
-Provision of earthing and bonding-labels at all-appropriate-locations . ( C3 )

Firstly .33. Reporting - Communicating theresults of periodic-inspection &Testing of an electrical-installation to the person ( Ordering the work )

What isPeriodic-inspection & Testing .

p.399: The purpose of this - Condition-report is toconfirm . so far as reasonably-practicable . whether or not theelectrical-installation . is in a
satisfactory-conditionfor continued-service . the report should-identify any damage . deterioration .defects and / or conditions which may give rise to danger .

 

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BS-7671: in itself . not-statutory-requirement but isprimarily a design-standard .

Requirements forElectrical-Installations BS-7671:2008:2011:
Introduction to BS-7671:2008: hasthe status of a British-Standard and relates . principally to the Design .Selection . Erection . Inspection and Testing . of electrical-installation(s)

Whilst not ( Statutory ) the Regulation represent whatis considered best-practice in these areas . there is a comment in theintroduction of both the
Electricity at Work Regulations -1989 and BS-7671: which states that compliance with BS-7671: is likely toachieve compliance with the relevant-aspects of the Electricity at WorkRegulations - 1989

This is why all reports should bein accordance with . Chapter 62 of BS-7671: so they can . if required . be used for a defense in the eventof an electrically-related-incident inthe workplace .

Electricity at Work Regulations -1989 . requires Inspection and Testing .

Electricity at Work Regulations -1989 . in Regulation 4(1) & 4(2) lay down the requirement to ensure that anElectrical0installation should be . design . installed . constructed andmaintained in a safe-manner at all times.

Electricity at Work Regulations .guidance-notes advice to Inspect and Test will satisfy the law and provide thedefense that the “ Duty-holder “ took all reasonable-steps and exercised alldue-diligence in order to avid committing an offence . Electricity at WorkRegulations - 1989 . Regulation - 29 .

Electricity at Work Regulations-1989 . ( Statutory )
17[SUP]th[/SUP] Edition 2008:2011 Non - Statutory )
Guidance-Note - 3 - ( Guidance )

If we look at the relationshipbetween the documents .

The introduction within the .Memorandum of Guidance on the Electricity at Work Regulations - 1989 . Statesthat “ Compliance with BS-7671: islikely to achieve compliance with the relevant aspects of the Electricity atWork Regulations .

GN-3 . Inspection & Testing .whilst providing good guidance . does state “ while the publisher andcontributors believe the information and guidance given in this work is correct. all parties must rely on their own skill and judgment when making use of it .( Effectively a disclaimer )

Regulation - 612.1.British-Standard .
States : That “ Where noprevious-documentation is available . Investigation of theelectrical-installation shall be undertaken prior to carrying out the (Periodic-inspection & Test )

Competence is a mix of thingswhich includes .

What makes a “ Competent-person“ Regulation - 16 of the Electricity at Work Regulations - 1989.States that “ No-person shall be engaged in any work-activity wheretechnical-knowledge or experience is necessary to prevent danger . Unless they possess such knowledge orexperience . or is under a degree of supervision as may be appropriate havingregard to the nature of the work .knowledge or experience of electrical-work . understanding the system beingworked-on . understanding all the hazards and precautions . and having theability to recognise danger and when it is safe to work .

 

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Voltage-drop-calculations.

Thevoltage-drop in a cable-conductor(s) isdirectly-proportional to the . circuit-current and the length of the cable-run.

(Vd) Voltage-drop = [ current - ( A ) x length of run ( m ) xmillivolt-drop-per ( A/m ) 1000 ]

Divisionby 1000 to convert-millivolts to . volts .

p.130. 525 : Voltage-drop in Consumer’s - Installation(s) .

Note : BS-7671: requirement - 525.1. limits the voltage-drop permitted between the ( Origin of the supply ) and the load to ( 3% ) for lighting and 5% forall other circuit(s) . for a 230Vsingle-phase-supply this is 6.9V for - Lighting and 11.5V for other-circuit(s) .

Regulation- p194 : Note .Verification of voltage-drop is not-normally . requiredduring-initial-verification .

 

[Jurasic Spark]

Voltage-drop-calculations.

Thevoltage-drop in a cable-conductor(s) isdirectly-proportional to the . circuit-current and the length of the cable-run.

(Vd) Voltage-drop = [ current - ( A ) x length of run ( m ) xmillivolt-drop-per ( A/m ) 1000 ]

Divisionby 1000 to convert-millivolts to . volts .

p.130. 525 : Voltage-drop in Consumer’s - Installation(s) .

Note : BS-7671: requirement - 525.1. limits the voltage-drop permitted between the ( Origin of the supply ) and the load to ( 3% ) for lighting and 5% forall other circuit(s) . for a 230Vsingle-phase-supply this is 6.9V for - Lighting and 11.5V for other-circuit(s) .

Regulation- p194 : Note .Verification of voltage-drop is not-normally . requiredduring-initial-verification .

Whichever way you look at it, volt drop is simply Ohm's Law where:
V = I x R

 

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Q ) . The prospective-short-circuit-currentat the Origin of the . consumer’s - installation must be taken into accountwhen .
A) . Selecting the type of .overcurrent-protective-device . to be installed .

Q ) . Design-calculations involving-conductor(s) and anovercurrent-protection-device . most likely satisfied when .
A ) . ( In ) is not less than .the design-current ( Ib )

Calculate - Actual ( Zs ) [ Zs = Ze + R[SUP]1[/SUP] + R[SUP]2 [/SUP] ] 0.23Ω + 0.6Ω = 0.83Ω . ( Zs ) = 0.83Ω
Calculate - Maximum-earth-fault-current . [ Uo /Zs = ( If ) ] 230V ÷ 0.83Ω = 277.1A
Formula : calculating .earth-loop-impedance . Zs = Ze + R[SUP]1[/SUP] + R[SUP]2 [/SUP] .

Multicore-cables.
The term “ Multicore “ is used to describe a cable wheretwo or more separately-insulated-conductors are contained within asingle-outer-sheath .

 

[Jurasic Spark]

Q ) . The prospective-short-circuit-currentat the Origin of the . consumer’s - installation must be taken into accountwhen .
A) . Selecting the type of .overcurrent-protective-device . to be installed .

Q ) . Design-calculations involving-conductor(s) and anovercurrent-protection-device . most likely satisfied when .
A ) . ( In ) is not less than .the design-current ( Ib )
Although this is true I think a better answer to that question would be In is not greater than the current carrying capacity of the cable it is protecting.

Calculate - Actual ( Zs ) [ Zs = Ze + R[SUP]1[/SUP] + R[SUP]2 [/SUP] ] 0.23Ω + 0.6Ω = 0.83Ω . ( Zs ) = 0.83Ω
Calculate - Maximum-earth-fault-current . [ Uo /Zs = ( If ) ] 230V ÷ 0.83Ω = 277.1A
Formula : calculating .earth-loop-impedance . Zs = Ze + R[SUP]1[/SUP] + R[SUP]2 [/SUP] .

Multicore-cables.
The term “ Multicore “ is used to describe a cable wheretwo or more separately-insulated-conductors are contained within asingle-outer-sheath .

......

 

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Useful -junk .

p.77 . p.85 . Values of ( k ) for common-materials . for calculation of theeffects of . fault-current . for the disconnection-times up to ( 5 - seconds )

Regulation(s)Table - 43.1 . [ t = K[SUP]2[/SUP] S[SUP]2[/SUP] / I[SUP]2[/SUP] ]

Where:
t ) is the duration in seconds .
S ) is the C.S.A. of conductor in ( mm[SUP]2[/SUP] )
I ) is theeffective-fault-current . in amperes . expressed for . a.c. as the rms-value .due account being taken of the current-limiting-effect of the .circuit-impedance .
k ) is a factor taking account of the resistivity. temperature-coefficient and heat-capacity of the conductor-material . and theappropriate initial and final-temperatures . for ( Common-materials ) the values of ( k ) are shown in Table - 43.1. (K[SUP]1[/SUP] )

70°C . ( Ief ) - 200A . ( t - 2 seconds ) . by calculation . 200A x[SUP]2[/SUP] x 2(t) =80. ( press on the calculator ( √ = ) then it will show . 282.8427125 ÷ ( k[SUP]1[/SUP] - 115 ) = 2.4mm[SUP]2 [/SUP]

Thermoplastic.
70°C ≤ 300mm[SUP]2 [/SUP]“ Under “ ◄◄ . Copper-conductor - ( k ) 115 . “ Under “
70°C > 300mm[SUP]2 [/SUP]“ Over “

 

[nexlar]

We want you to be totally happy with our phone and broadband services – even the things that are beyond our control. So we’ve compiled a list of information we think you may find useful.

 

[SLSpark]

Looking for info on 2391 testing & inspection course anyone help ?

 

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Q) . An electrical-installation-certificate should be signed by .
A) . Competent-person . ( this Question. has Answered the other two - Q/As ) -&-s will fling at you .

Appendix- 6 . informative . p.389 .
Electrical-Installation-Certificate. required by part - 6 . should be made out and signed or otherwiseauthenticated by a ( Competent-person ) or person or persons in respect of the design. Etc . ( i ) ( ii ) ( iii )
(( i ) EIC ) . (( ii ) MWC ) . (( iii ) EICR )

(iv)Competent-person will . as appropriate totheir ( Function-under ) ( i ) (ii ) ( iii ) above . have asound-knowledge and experience-relevant to the nature of the work-undertakenand to the . technical-standardsset down in these Regulation(s) .
2394:- Be fully versed in the . Inspection &Testing-procedures . contained in the Regulation(s) & ( Employ-adequate-testing-equipment )

 

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RCDs
Shouldbe tested at . 50% . 100% . 500% .
RCD- providing-additional-protection of their rated-residual-operating-current ( IΔn ) . 500% . x5 .

Wherean RCD is employed to achieve the . disconnection-time required by Table -41.1. it is necessary to confirm thatthe maximum-earth-fault-loop-impedance (Zs ) stated for a . particular sensitivity of the RCD in . Table - 41.5. are not exceeded in thecircuit to which they protection .

 

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Protective-device(s) is used to ( Achieve the disconnection-time(s) required by table -41.1. whether Fuse . Circuit-breaker . or RCD . To confirm that the required-disconnection-time can be achieved by (Testing the protective-device ) We confirm that the . earth-fault-loop-impedance. of the protected-circuit doesnot-exceed the relevant-tabulated-maximum-earth-fault-loop-impedance for thetype . ( of protective-device we areusing )

 

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Q) . Where a clamp is used for bonding-purposes . a permanent label shall befixed in a visible position with the wording ?
A) . “ Safety-Electrical-Connection “ Do Not Remove . 514.13.1 .p.118 . ( EICR -. C2 . C3 . ??? )

 

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Underpinningknowledge 2392-10
Thecandidate will be able to :

Identifythe general requirements for inspection and testing of installations .

Statethe need for diagrams . chats or tables to be available prior to theverification process .

Indentifythe items to be checked during the inspection process .

Statethe tests which may need to be carried out on initial verification .

Comparetest results with relevant criteria .
Statethe requirements for the issue of
-Electrical Installation Certificate . ( EIC )
-Minor Electrical Installation Work Certificate . ( MEIWC )

 

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Q) . where it is necessary to limit the consequences of the risk of fire due tofault-currents . which of the following RCDs is used ?
A) . RCD with operating-current notexceeding 300mA
Q) . What is the maximum operating current for an RCD which may supply portableequipment used outdoors . ?
A) . 30mA . p.54 . 411.3.3. (ii)
Q) . Every electrical installations shall be divided into circuits to . asnecessary to . ?
A) . facilitate safe inspection . testingand maintenance . p.46 . 314.1 . ( ii )
Q) An overload protective device installed at the origin of a circuit must havea breaking capacity of . ?
A) . equivalent or more that the prospective-short-circuit-current .
Q) The maximum disconnection time for a 230V a.c. final-circuit not exceeding32A . with a TT - supply . ?
A) . 0.2 seconds . p.53 . Table - 41.1
Q) In a TT- system . automatic-disconnection of the supply in case of a fault ina 230V a.c. final-circuit not exceeding 32A . ?
A) . 0.2 seconds . p.53 . Table - 41.1
Q) . In a TN-S system . the maximum-earth-fault-loop-impedance ( Zs ) when using a 32A . type B circuit-breaker instantaneous-operation would be . ?
A) . 1.44Ω . p.56. Table - 41.3.

Chapter- 51
510.2. Every item of equipment shall be selected anderected so as to allow for compliance with the regulations in this chapterand other-parts of BS-7671: andManufactures-Instructions .

Q) . A copy of the distribution-board-schedule shall be located with ?
A) . The distribution-board . p.117 .514.9.
Section514 . Identification and Notices .
514.8.Identification of protective-device . Circuit-protective-devices arerequired to be arranged and identified so that the circuit-protected may beeasily-recognised .
514.9.Diagrams . A legible diagram . chart or table . or equivalent form ofinformation . must be provided indicating a range of information .
Q). State . the items that should be included in a distribution chart to meet theabove requirements - 514.9.
Forsimple-installations the information may be given in a . Schedule ( Schedule ofcircuit-details for the installation ) . a durable-copy of which relating tothe distribution-board . shall beprovided within or adjacent to each distribution-board .

 

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514.13.Warning notices . Earthing and bonding-connections .
514.13.1. A durable-label to BS-951 with the words “Safety-Electrical-Connection “ Do Not Remove . shall be permanently fixed in avisible-position at or near .
i)the point of connection of every earthing-conductor to an . earth-electrode .
ii)the point of connection of every bonding-conductor to an .extraneous-conductive-part
iii)the main-earth-terminal . where separate from main-switchgear .

 

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2394: Q ) . Defects identified during aninitial-verification should be ? thisone always comes up .
A) . Made good before the certificate is issued .

Regulation(s), Initial - Verification . p.196
632.4. Defects or omissions revealed during .inspection & testing of theinstallation-work covered by the ( Certificate ) shall be made good before the Certificate is issued .

Q) . An electrical-installation-certificate . must indicate responsibility forthe installation(s) . A ) . Design . construction . testing & testing. p.389 .
(v) ( EIC ) will indicate the responsibility for . design.construction . inspection & testing . whether in relation to new-work . or further-work . on an existing-installation .

Where. design . construction . inspection & testing are the responsibility of one-person a .Certificate with a ( single-signature ) declaration . Etc .

 

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Isolation-proceduresfor Safe-Working .

The only safe-method ofIsolation is by means of an . Individual-locking-device . the system you working on cannot be .energised without the removal of the locking-device .

p.29 . Isolation isdefined as

2394: afunction intended to cut-off for reasons of safety the supply from all . or a discrete-section . of the installation byseparating the installation or section from every-source of . electrical-energy.

Useful-junk

A “ Volt-stick “ is not-considered to be used forsafe-isolation-procedures and can only be . considered to be an ( Indicator that voltage ispresent )

 

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Re-cap .

Functional-tests : GN-3. p.76 . 2394: Table 3.10.2. Testing tobe carried-out where practicable on .Existing-Installation(s) .

Functional-tests of . circuit-breakers . isolators & switching-devices. Manual-operation . to confirm that the devices disconnect the supply

Functional-testing -612.13.1. :

 

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Q) reasons for testing an electrical-installation.

Q) Perform avisual-inspection of any domestic-installation(s) .
Visual-inspection shouldprecede testing .
Reason : Prior to theInstallation being made-live . it is necessary to inspect any part of theinstallation during construction . as these parts . 2394 . in our case . willbe concealed .

 

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Recap .

Can I carry out analteration or addition to an existing-installation that has inadequate-earthing and / or bonding-arrangements .

No - Any alteration oraddition to an existing-installation must comply with the current-edition ofBS-7671: including any amendments . This requires any earthing and bonding-arrangements. upon which the alteration or addition relies for safety to be adequate .

Refer . 132.16. 633.2. 411.3.1.1.

 

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Periodic-Inspection andTesting . ( Careful-scrutiny backed up by testing )

Scenario :
a) . What types ofInspection and Tests . need to be carried-out . Initial-verification for New-work . and Periodic-inspectionand test for the . Existing-installation .

b) Sate : the documentthat should be completed and why
an Electrical-Installation-Certificate for new-work .
Additional-circuitshave been installed and a . Periodic-Inspection for the Existing-installation . ( EICR )

Both of these documentsmust be accompanied with a . Schedule of Inspection and a Schedule oftest-results .

Re-call . p.389 .
vii ) An ( EICR ) willindicate the responsibility for the inspection and testing of an . Existing-installation . within the extentand limitations specified on the report .

viii) Schedules of inspection and Schedules oftest-results as required by part - 6 should be issued with the associated .Electrical-Installation-Certificate . or Electrical-Installation-Condition-Report .

Re-call . p.389 .
Electrical-Installation-Certificateswill indicate the responsibility for design . construction . inspection andtesting . whether in relation to ( New-work ) or further-work on an .existing-installation .

viii) Schedules of inspection and Schedules oftest-results as required by part - 6 should be issued with the associated . Electrical-Installation-Certificate . or Electrical-Installation-Condition-Report.

Periodic-Inspection . Q). if no documentation is available for the installation what action is required. some exploratory-work . to establishthe criteria .

An Inspection and Testis to be conducted on a new-installation . 2394:
State :
a) the type ofverification to be carried out .
b) the documentationthat will need to be completed .

a) Initial-verification.
b)Electrical-Installation-certificate . ( EIC )

* i) Electrical-Installation-Certificate .ii) Schedule of test-results . iii) Schedule of inspection .

a) . if the Ring-final-circuit( R[SUP]1[/SUP] + R[SUP]2[/SUP] ) is0.72Ω . calculate the approximate-reading of ( Zs )
Zs = Ze + ( R[SUP]1[/SUP] + R[SUP]2[/SUP] ) = 0.2 + 0.72 = 0.92Ω .

b) . if themaximum-tabulated ( Zs ) for this circuit is ( 1.2Ω ) calculate if the reading in ( a ) isacceptable .

there are nocorrection-factors stated . use the rule of thumb .
1.2 x 0.75= 0.9Ω < 0.92Ω measured . ( Circuit-fails )

c) . State : whatfactors need to be considered before measured .earth-loop-impedance-values are comparedagainst maximum-tabulated ( Zs ) values .
i) .Ambient-temperature-factors . when not measured at 20°C .
ii) .Cable-temperature-factors . not at its operating-temperature .

Record the Test-results.

Ring-Final-Circuit -conductor .
2.5mm[SUP]2[/SUP] T&E cable has a 1.5mm[SUP]2[/SUP] protective-conductor .
In this case multiplythe résistance of the . Line or Neutral-conductor . by a factor of ( 1.67 ) tocross-check the . protective-conductor-readings - 2.5 ÷ 1.5 = 1.67 .

 

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Knowledge ofFundamental-initial-verification . Some handy - revision .

By definition p.29 : Inspection
Examination of an electrical-installation. using all the ( Senses as appropriate )

Q ) . Overloaded-windson a . 3-phase-motor may be identified in the first-instance by ?
A) . Smell .
Sight .
Touch .
Taste .

Q ) . Anearly-indication of an . overloaded-circuit could be found by ?
A) . Using-senses .
Continuity-test .
An insulation-résistance-test.
Anearth-fault-loop-impedance-tester.

Q ) . When diagnosingand locating a . loose-connection the most-effective-sense to use would be ?
A) . Touch .
Smell .
Taste .
Hearing .

2394:
Q) . The safest-methodof making sure an installation is safe to work on would be ?
A) . To follow thesafe-isolation-procedure .

Q) . During an external-loop-impedance-test. the main-earthing-conductor should be ? GN-3 p.53
A) . Disconnected . ( No-Parallel-path )

Q) . An earth-fault-loop-impedance-tester. should only allow-current to flow for . ? GN-3 . p83 / 4.5
A) . 40mS .

Q) . An installationhas a . prospective-fault-current-measured at ( 2.3kA ) and a .prospective-short-circuit-current-measured at ( 2.5kA ) The value that should .be recorded would be ?
A) . The highest .

Q) . Whentwo-bonding-conductors of equal-length .are connected in parallel the résistance would . ?
A) . Halve .
Increase.
Decrease.
Double .

Q) . if the . C.S.A. ofa protective-conductor increases . ?
A) . Résistance-decreases.
Résistance-increases.
The ( Zs ) readings-increases.
Résistance reminds thesame .

Q) . The frequency of .periodic-inspections should be determined by : the type and use of installation. the frequency of maintenance and . ?
A) . Theexternal-influences to which the . the installation is subjected . p.393 / Part - 3 . Essential-Tests .
Q) . Aminor-work-certificate it is not . necessary to record . ?
A) . ( Ze )
Zs .
RCD-operation .
Installation-résistance.

Zs ) . 612.9.Earth-fault-loop-impedance . (Circuit-loop-impedance )
Where protective-measuresare used which require a . knowledge of earth-fault-loop-impedance . therelevant-impedances shall be measured . 2394:

Q) . A minor-work-certificateshall be issued where . ?
A) . An alterationnot-requiring an . additional-circuit is needed .

Q) . it is important to. test an installation in the . correct-sequence-because . ?
A) . Each-test-relies .on the previous to be correct .

 

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Using the wife’sglasses . sorry
Q) . Aminor-work-certificate it is not . necessary to record . ? p.393 / Part - 3 .Essential-Tests .
A) . ( Ze )
Zs .
RCD-operation .
Installation-résistance.

 

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Q) . Theprospective-fault-current at the . origin of an electrical-installation must betaken into account when ?
A) . Selecting the typeof . overcurrent-device to be installed .
Assessing theearthing-arrangement .
Applying-diversity tothe installation .
Estimating the .external-earth-fault-loop-impedance .

Q) . it is a good-ideawhen performing an . insulation-résistance-test on a large-installation . tosubdivide-circuits to avoid ?
A) . False-readingsfrom . parallel-paths .

Q ) . Overloaded-windings on a .3-phase-motor may be identified in the first-instance by ?
A) . Smell .
Sight .
Touch .
Taste .

Q ) . Thenon-statutory-document-concerning the care and use of test-instruments . leadsand probes would by ?
A) . Guidance - Note .GS-38. ( H&S Guidance-note - GS-38 )
Guidance-note - 3 .
BS-7671:2008:2011:
The Electricity at work-regulations 1989 .

Q ) . Aninitial-verification should be carried out on ?
A) . A new-installation.

Q ) . AnElectrical-installation-certificate . must indicate responsibility for the installation’s. ?
A) . Design .construction . inspection & testing . of the work .

Q ) . Electrical-installation-certificate. should be signed by .
A) . A competent-person.

Q ) .BS-7671:2008:2011: has a separate-section or part that is solely-designated to . inspection & testing . this documentis classed as . ?
A) . Anon-statutory-document .

Q ) . Prior to performing-live-tests . &before-energising an installation . you should . ?
A) .Inform-other-people in the area .

 

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Q ) . On preparing to carry out a full-initial-verification . inspection &test on a large-office-block . which of the following items would . be unnecessary at this point . ?
A) . The presence of .inducting-lighting .
The nominal-voltage .
The prospective-fault-current.
The type & ratingof the . protective-device at the origin of the installation .

2394 : as an Inspector.
Q ) . On-disassembling a ceiling-rose-during-completion. of the schedule of inspections on a ( EICR ) you note that ablue-insulated-conductor . is in the Line-terminal . even though thecircuit-work-fine . this might-fail-inspection due to . ?
A) . Identification of conductors.
Polarity-verification .
Connection-method .
Cable-routing .

Q ) . When-testing a ring-final-circuit-protected bya . BS-EN-61009-1 30mA -RCBO . with a RCD-tester at ( x5 ) it should - disconnect ?

A) . Within - 40mS .
Q ) . When-testing at ( 100% ) an RCD -protected-socket-outlet to ( ► BS-7288 ) should operatewithin . ?
A) . 200mS .
Q ) . A . BS-EN-61009-1 30mA RCBO - tested at ( x1 / 100% )should-operate within . ?
A) . 300mS .
Q ) . What-type of test-instrument may give . areading such as ( 16.8mS )
A) . An RCD tester .
** . Q ) . The most-convenient-method of determining thevalue of the . ( PFC ) at the origin of an existing-installation . would be by ?
A) . Measurement .

 

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Q ) . 2394:
After wiring an additional-light-fitting. into a new-conservatory by extending from an ( Existing-circuit ) on completion you should -issue . ?
( MEIEC ) Minor-electrical-installation-works-certificate.
( EIC )Electrical-installation-certificate .
( EICR ) Electrical-installation-condition-report.
Building-control-notification.

Q ) . Before commencingthe . inspection and testing of a new-installation . the information you shouldhave available would be . ?
The . Maximum-earth-fault-loop-impedance. values
The . Earthing-arrangements. ( What do we confirm first )
The . Presence ofany-surge-protective-devices
The . Proximity of theDNO -supply-transformer .

Q ) . Two-ways in whichan electric-shock could-occur are . ?
Direct andfault-contact
A) . Basic andfault-contact
Direct andbasic-contact
Basic and earth-contact.

Q ) . Before commencingthe . inspection and testing of a new-installation . the information you shouldhave available would be . ?
The .Earth-fault-loop-impedance
The . Insulation-résistance-readings for the installation
The . External-loop-impedance. ( Do we have an Earth )
The ( R[SUP]1[/SUP] + R[SUP]2[/SUP] ) values of each-individual-sub-main

Q ) . When-performingan . earth-electrode-test . the most-reliable-results . would be when the . distance between the earth-electrodeand the current-spike is . ?
At least ( 5 - times )the maximum-dimension of the electrode-system
At least ( 10 - times )the maximum-dimension of the electrode-system
GN-3 . p.49 . is at least - ten-times .
Between . 2 and 5m away .
Within 2 metres of each-other .

Q ) . During acontinuity of . ring-final-conductors-test . 10-sockets give a ( R[SUP]1[/SUP] + R[SUP]2[/SUP] ) reading of ( 0.68Ω ) but one-socket gives a reading of ( 0.92Ω ) this could . indicate . ?
Short-circuit .
High-résistance-fault .
Missing-earth-connection.
Spur on the circuit . ( What would give you a higherreading ) indicating a - Spur . ( 0.92Ω )

 

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Q) . when performing an . earth-fault-loop-impedance-test . thequickest-method of determining-compliance with BS-7671:2008:2011: would be bycomparing the results to . ?
BS-7671:2008:2011:
The . designer-notes
Manufactures-ratings .
A ) . Guidance-note - 3 . Complying

Q) . Ona small-installation-containing . no-distribution-circuit(s) . an insulation-résistance-test can be .
Ignored
Assumed to be correct .
A) . Tested as a whole .
Avoided
A) GN-3 . p.40 .
Simple-installations that contain no-distribution-circuit(s) should preferably be tested as a whole . refer . fig -2.4a

 

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Incorporating Amendment Number - 1: 2012. ( page - 1 )

Mock Exams .

1. The Regulations . ( BS-7671:2008 ) do not apply to ?
a) . Residential-premises
b) . Industrial- premises
c) . Lighting-protection
d) . Street-furniture
part - 1 . 110.2. P.15.

2) . the Regulations do not apply to ?
a) . Offshore-installations
b) . Mines & Quarries
c) . Lift-installations
d) . Low-voltage-generators
part - 1 . 110.1. P14.

3) . Which of the following-documents are deemedNon-Statutory ?
a) . BS-7671:2008:
b) . EAWR . 1989
C) . HASAW . 1974
D) . ESQCR. 2002
part - 1 . 114.1 . p15.

4) . Parts - 3 / 7 . of BS-7671:2008 . are explained inrudimentary terms within ?
a) . Chapter - 13
b) . Chapter - 12
c) . Part - 3
d) . Appendix - 5
part - 1 . 120.3. p16

5) . Basic-protection is defined as ?
a) . Protection against shock under fault-conditions
b) . Protection against electricshock under fault-free-conditions
c) . Protection against contact with. Live-parts underfault free-conditions
d) . Protection against faults . under sound electrical-conditions.
part - 2 . Definitions’ . p.23

6) . Equipment in which protection against .electric-shock does not rely onbasic-insulation only is described as ?
a) . Double-insulated-equipment
b) . Class - 1 . equipment
c) . Class - 11 . equipment
d) . Class - 11 1. equipment
part - 2 . Definitions’ . p.25

8) . A voltage of 250V a.c. ( r/ms ) would be defined as ?
a) . Band - 1
b) . Extra low-voltage
c) . High-voltage
d) . Low-voltage
part - 2 . Definitions’ .

9) . In determining-maximum-demand. Diversity “ may be applies . which is ?
a) . Taking the sum of all the . protective-devices fromany CCU
b) . Taking into account thatnot all loads .will be switched on . at the same-time
c) . Taking into account that all loads . doubtless willbe engaged at the same-time
d) . Ensuring that an economical . and reliable-designpreference is utilised
part - 3 . 311.1 . p.41

10) . Every-installation is divided into circuit(s) inorder to ?
a) . Ensure simplicity of isolation
b) . Comply with European-standards
c) . Avoid hazards andprevent . inconvenience in the event of a fault
d) . Allowindividual-energising of. Circuit(s) which are not isolated
part - 3 . 314.1. p46

11) . A buildingmade entirely out of wood. Would be categorised for External-influence as ?
a) . CA2
b) . CA1
c) . CB3
d) . CB4
Appendix - 5 . p377

12) . The maximum-disconnection-time . for an a.c. . TN - circuitrated at 230v is ?
a) . 0.04 Seconds
b) . 0.1 S
c) . 0.4 S
d) . 0.2 S
part 4 . Table - 41.1 . p53

 

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13) . The maximum ( Zs ) for a BS-EN-60898 . Type - C .circuit-breaker rate at . 16A with a . 0.4 second-disconnection-time is ?
a) . 2.87Ω
b) . 1.44Ω
c) . 0.72Ω
d) . 1.15Ω
part - 4 . maximum ( Zs ) tables - 41.3 . p56

14) . For a TT -system the maximum-earth-fault-loop-impedance for a 100mA . BS-EN-61008-1 . RCD in a 230V circuit is ?
a) . 500Ω
b) . 460Ω
c) . 167Ω
d) . 100Ω
part - 4 . Table - 41.5 . p.57

16) . Where basic-protection is employed in . the form ofa barrier or enclosure . any horizontal-top-surface must meet a protection-level of atleast ?
a) . IPDXX
b) . IP2X
c) . IPXX3
d) . IP4X
PART - 4 . 416.2.2. P67

17) . Except if made from adequate-material . aluminaire-rated at . 200Watts should belocated-away . from combustible-material by
a) . 0.3m
b) . 0.5m
c) . 0.8m
d) . 1.0m
part 4 . 422.3.1 . p74 ……. ( ii) OVER 100 and UP to 300W - 0.8m )

18) . To avoid burning . a non-metallic-part-intended . to betouched but not hand-held cannot exceed ?
a) . 80°C
b) . 85°C
c) . 90°C
d) . 95°C
part - 4 . table - 42.1 p.77

19) . in relation to voltage-disturbances . the résistance of the earthing-arrangement . at the transformer is referred to . within the areaof symbols . as
a) . R[SUP]A [/SUP]
b) . R[SUP] B[/SUP]
c) . R[SUP]D [/SUP]
d) . R[SUP] E[/SUP]
part - 4 . 442.1.2. p89

20) . Every-core ofa cable shall be identifiable at is . terminations and preferably-throughoutits length by ?
a) . Colour-code-only
b) . letter-code-only
c) . number-code-only
d) . one or more of the above
part - 5 .

21) . An appropriate -colour for a . PEN - conductor should be ?
a) . blue-through its length with . green-markings at theterminations
b) . green & yellow -through its length with . blue-markings at theterminations
c) . green & yellow -through its length with . brown-makings at the terminals .
d) . green-through its length with . yellow-markings at the terminals
part - 5 .

22) . A permanent-label with the words . “ Safety-Electrical-Connection - Do Not Remove “ complies with ?
a) . BS-728
b) . BS-1363
c) . BS-951
d) . BS-423
part - 5 .

23) . A cable buried-underground but not in . conduit orducting for mechanical-protection must-incorporate ?
a) . An earthed-armour or metal-sheath or both
b) . A surface-covering of . 50mm thickness-paving-stones
c) . A clear-surface . warning-notice . informing of its location
d) . A PVC - outer-sheath
part -5

24) . The de-rating-factor for a cable surrounded by . 50mm of thermal-insulation is ?
a) . 0.88
b) . 0.78
c) . 0.63
d) . 0.51
part - 5 - table . 52.2 . p.129

25) .In an ( LV - installation ) supplied-directly from a public ( LV) distribution-system themaximum-volt-drop . on a lighting-circuit between the origin . and load-pontshould be no greater than ?
a) . 6% . b) . 5% . c) . 4% . d) . 3% .
part - 5
.

 

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26) .Every-electrical-inspection shall be accessible forinspection . testing and maintenance-purposes . except for which of theflowing ?
a) . A connectionmade in a junction-box. Beneath floorboards
b) . A connectionmade within a . motor-control-unit
c) . A connectiondesigned to . withstand fault-current
d) . A compound-filled or. Encapsulated-joint
part - 5

27) . The rated - RCD -operating-current of such . adevice-installed as a protection againstrisk of fire . in a TT - system shall have a value of ?
a) . 30mA
b) . 100mA
c) . 300mA
d) . 500mA
part - 5

28) . The maximum-prospective-short-circuit-current . or earth-fault-current in. a circuit should not exceed ?
a) . Theoperating-current . of the circuit switching-devices
b) . Therated-breaking-capacity of . any associated-protective-device
c) . Thedesign-current . of any RCD in circuit
d) . Therated-operating-current. Of any RCD in circuit
part - 5

29) . Which of thefollowing. Switching-devices may be satisfactorily-utilised for. The purpose of isolation ? Table - 53.2 .
a) . BS-EN-60669-2-4
b) . BS-EN-60669-2-3
c) . BS-EN-60669-2-1
d) . BS-EN-60669-1
part - 5

30) . When using bare-conductor(s). in extra-low-voltage .lighting-installation(s) supplied from a. safety-isolating-transformer the .minimum-permissible-cross-sectional-area . of conductor(s) must be ?
a) . 1.5mm[SUP]2 [/SUP]
b) . 2.5mm[SUP]2 [/SUP]
c) . 4mm[SUP]2[/SUP]
d) . 6mm[SUP]2 [/SUP]
part - 5

31) . Suspension-devices for. ELV - luminaries must inany-case be capable of supporting atleast ?
a) . 5Kg
b) . 7.5Kg
c) . 10Kg
d) . 20Kg
part - 5

32) . An automatic-electrical-safety-service-supply. Classedas medium-break must. In the event of losing the main-supply. Intake thesafety-services-supply . in a time period of ?
a) . Between 0.15. & 0.5 seconds
b) . Between 0.5. & 5 seconds
c) . between 5. and 15 seconds
d) . Greater than 15 seconds
part - 5

33) . The minimum-value of. Insulation-résistance for a230V. system . must be ?
a) . ≥ 0.25MΩ
b) . ≥ 0.5MΩ
c) . ≥ 1.0MΩ
d) . ≥ 2.0MΩ
part - 6 . Table 61. p.191 . ( Minimum- Values )

34) . Correct polarity must ensure. That every - ESlamp-holder . have their outer orscrewed-contacts-connected . to the neutral-conductor . except for ?
a) . E14. & E27. lamp holders
b) . E14. & BS-EN-60895 . lamp holders
c) . E27. & BS-EN-61009 . lamp holders
d) . E11. & E24. lamp holders
Part - 6. 612.6.p.192

35) . To comply with. Part - 6 of BS-7671: .Periodic-inspection & Testing shallbe. Specifically-undertaken by ?
a) . A formally-qualified. Test-engineer
b) . A person deemed as the “ Duty-holder “ of thecompany carrying out. The work
c) . A expressly-skilled-person
d) . A competent-person.
Part - 6. 621.5. p.195

36) . Zone - 2. of a bathroom is restricted to the .highest-water-outlet. Or the horizontal-plane. Lying abovefinished-floor-level. By ?
a) . 3.00m
b) . 2.50m
c) . 2.25m
d) . 2.00m
Part - 6. p.202

 

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37) . In zone - 3. of sauna-equipment must be able towithstand a minimum-temperatureof ?
a) . 100°C
b) . 120°C
c) . 125°C
d) . 170°C
part - 7. 703.512.2. (iii) p.213

38) . A marinas-equipment installed above a jetty. Or wharf.Which is likely to encounter-water-jets . shall be selected to comply with. External-influence-levelsof ?
a) . ( AD4 ) : IPX4
b) . ( AD5 ) : IPX5
c) . ( AD6 ) : IPX6
d) . ( AE6 ) : IPX5
part - 7 . 709.512.2.1.1. (ii) p.226

39) . For a BS-88-2.2. fuse rated at . 25A . to obtain a .0.4s - disconnection-time . it would require aminimum-prospective-fault-current of ?
a) . 160A
b) . 130A
c) . 100A
d) . 85A
Appendix - 3. Time / current - graph . p.299 . ( E & G )

40) . A 30 Amp .Semi-enclosed. BS-3036 fuse . receiving a prospective-fault-current of 210A ? ( C f - 1.45. 1.45 ÷ 2 = 0.725 )
a) . 5.0 . seconds
b) . 1.0 . seconds
c) . 0.4 . seconds
d) . 0.2 . seconds
Appendix - 3. Time / current - graph . p.297 . ( E & G )

 

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1) . A building-constructed solely of wood . would have an. External-categoryof ?
a) . CA2
b) . CA1
c) . CA3
d) . CA4
Appendix - 5 .p.377

2) . As. BS-7671:is .
a) . Documentdesigned solely. For the use of electricians
b) . legal-documentused . in a court of law
c) . Non-statutory-document
d) . Statutory-document
114.1. p.15 .. ( The Regulations are Non-statutory )

3) . The fundamental-principles of. BS-7671: covering the. protection against voltage-disturbances . etc States - that the installation shall have anadequate-level of immunity against ?
a) . motors-running
b) . the operationof circuit-breakers
c) . atmospheric-events
d) . voltage-recovery
131.1. p.16

4) . Thefundamental-principles of. BS-7671: covering the . protection against voltage-disturbances. etc States - that the installationshall have an adequate-level of immunityagainst ?
a) . the weather
b) . electromagnetic-disturbances
c) . voltage-loss
d) . vibration
131.1. p.16

5) . what is themaximum ( Zs ) for a 10A . type- Ccircuit-breaker protecting a . standard-discharge type-lighting-circuit ?
a) . 1.15 Ω
b) . 2.30 Ω
c) . 1.44 Ω
d) . 1.92 Ω
table - 41.3 . p.56

6) . A double-insulated. Hand-heldelectric-drilling-machine is knownas ?
a) . Class - 11 equipment
b) . A DeWat
c) . Class HI equipment
d) . Class - 1 equipment
Definition . p 25

7) . An Electrical-Installation-Certificate should be signed by ?
a) . thelocal-authority
b) . A competent-person
c) . The customer
d) . The DNO
Appendix - 6 . p389

8) . When considering-external-influences . the code ( AD4 ) requires . IP - rated-equipment to ?
a) . IPXO
b) . IPX1
c) . IPX4
d) . IPX5
Appendix - 5 . p381

9) . The external-influence-code . ( AD1 ) requires. IP - rated-equipment to ?
a) . IPX4
b) . IPX1
c) . IPX0
d) . IPX2
Appendix - 5 . p381

10) . When considering-external-influences. the code ( AA5 ) relates to the . ambient-temperature-range ?
a) . ( - 5°C to +45°C )
b) . ( - 60°C to +5°C )
c) . ( +5°C to +40°C ) ***
d) . ( -25°C to 0°C )
Appendix - 5 . p378

11) . When considering-external-influences. the code ( AA1 ) relates to the . ambient-temperature-range ?
a) . ( - 5°C to +45°C )
b) . ( - 60°C to +5°C ) ***
c) . ( +5°C to +40°C )
d) . ( -25°C to 0°C )
Appendix - 5 . p378

12) . Electrical-installationsshall . be divided into-circuits to ?
a) . allow easier-access to the installation
b) . allowmore-even . distribution of power
c) . allow for expansion without . changing the maximum-demand
d) . reduce-electromagnetic-interference
314. 1 . ( v ) p.46

13) . One method of determining the . external-loop-impedance . istaking a reading at ?
a) . The origin of supply
b) . The supply and. furthest-outlet
c) . The supply and subtracting the values of ( R[SUP]1[/SUP] + R[SUP]2[/SUP] )
d) . thefurthest-outlet from the supply-origin
O.S.G. 10.3.6. P.101

 

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Q) . Single-phase-circuit . using 2.5mm[SUP]2 [/SUP] - single-corepvc -cables in conduit . supplies a design-current of 20A . if the cables are .15m - long and have a rated-voltage-dropof . 18mV / A / m . theactual-voltage-drop . will be
a) . 2.5V
b) . 5.4V
c) . 6V
d) . 16.6V
( 18mV/A/m . x . 20A x 15m ) ÷ 1000 = 5.4V . 18 x 20 x 15 = 5400 . ÷ 1000 = 5.4V

 

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Q) . A protective-conductor connecting the .main-earthing-terminal of an installation to an . earth-electrode or to other means of earthing iscalled .
a) . Main-protective-conductor
b) . Earth-continuity-conductor
c) . Circuit-protective-conductor
d). Earthing-conductor.

Q) . When carrying out an. Inspection of anew-installation . its not necessary to verify the ?
a) . Total . earth-fault-loop-impedance for each-circuit
b) . Connection ofconductors
c) . Methods of protection. against electric-shock
d) . Presence ofdiagrams. Instructions and similar-information .

Q) . Certain information must be . made available topersons carrying out inspection & testing. Of an installation before thetesting-commences . One such-item ofinformation would be ?
a) . Name of theclient
b) . Name of theperson who. Designed the installation
c) . Length ofcable-runs . in the installation
d) . Any circuit orequipment. Vulnerable to a typical-test

Q) . When carrying out a. visual-inspection of anelectrical-installation. Which one of the following does. Not have to beverified ?
a) . The method ofprotection. against electric-shock
b) . The electricity-supplier
c) . Connection of conductors
d) . Presence ofundervoltages-protective-devices

Q) . When an addition is made to an. Existing-installation.The contractor shall record on the . Electrical-Installation-Certificate . orthe Minor-Electrical-Installation-works-certificate any ?
a) . Changes inownership
b) . Records ofrepair over. the last five-years
c) . Defects in the existing-installation
d) . Voltage-dropin the longest-circuit

Q) . An insulation-résistance-test. Is to be carried outon a . 3 - phase 400V circuit . thetest-voltage and minimum-acceptable-reading would be ?
a) . 250V .d.c. & 0.5MΩ
b) . 500V .d.c. & 0.5MΩ
c) . 500V . d.c. & 1MΩ . for the sake of. Chief-examiners report .
d) . 800V .d.c. & 0.5MΩ .

Q) . If an area within an installation. Undergoes a ( 10°C ) rise in ambient-temperature . the effect on thecurrent-carrying-capacity of cables will be to ?
a) . Decrease the value of ( Iz )
b) . Increase thevalue of ( Iz )
c) . Leave ( Iz )unchanged
d) . Increase thefault-current by . 10 - per cent

Q) . For protection against overvoltage a . 230Velectricity-meter should have an impulse withstand of ?
a) . 6kV
b) . 4kV
c) . 2.5kV
d) . 1.5kV

Q) . With reference to the nature of the supply. Which oneof the following can be determined by . calculation . enquiry ormeasurement ?
a) . Maximum-demandof the installation
b) . The rating ofthe circuit-protective-device
c) . The prospective-short-circuit-current . at the origin ofthe installation
d) . The C.S.A. ofthe tails

Q) . Which one of the following is . not part of the requirements for fault-protection
a) . Protective-earthing
b) . Protective-equipotential-bonding
c) . Automatic-disconnection
d) . Protection byinsulation of live-parts

Q) . BS-7671:2011: indentifies that the . C.S.A. of a conductor shall be determined by ?
a) . The admissible-maximum-temperature
b) . Thenominal-voltage
c) . Voltage-tolerances
d) . Theearthing-system

Q) . A residual-current-device ( RCD ) works by ?
a) . Magnetic-device-operating in the . event of a fault between. line & earth
b) . Magnetic-device-operatingin the . event of a fault between . neutral & earth
c) . Thin-element-operatingin the . event of a fault between . neutral & earth
d) . Thin-element-operatingin the . event of a fault between . line & earth
O.S.G. FICD - 11.0. P.105

Q) . A RCBO offersprotection against ?
a) . Short-circuit-current
b) . Short-circuit . overload-current and . earth-fault-current
c) . Short-circuit and overload-current
d) . Basic-contact
O.S.G. 3.1. p.23

 

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Q) . A person who is described as neither , askilled-person . nor an instructed-person is ?
a) . Competent-person
b) . Ordinary-person
c) . not an Electrician
d) . able to carryout . electrical-work in domestic-installation(s)
Definitions

Q) . in a TT -system when an overcurrent-protective-device is used the following condition must be . met: ( Zs x Ia ≤ Uo. Ia represents )
a) . The current causing-operation of the device within the time-stated in Table - 41.1
b) . The prospective-fault-current
c) . The nominal-rating ( In ) of the device
d) . 30mA

 

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BS-7671:2011: 2394 : Regulation(s) recongnises that installations . can only beverified . so far as is reasonably-practicable. “ In there own words “ Inspection & Testing .BS-7671:2011: differentiatesbetween .2394: Initial - verification . - New-work .- Additions & alterations . Chapter - 61 : Initial - Verification . p.189i) Inspection & Testing . Every-installation shall. During erection and on completion before being putinto service. Be Inspected & Tested to verify . sofar as is reasonably-practicable.Etc . 2395: Periodic inspection &Testing : Existing - installation . reasonably-practicable. Approach ( Careful-scrutiny ) backed up by testing .