Re-take - Useful Information for 2394 :

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BS-7671:2011: 2394: Regulation(s) recongnises thatinstallations . can only be verified . so faras is reasonably-practicable. “ In there ownwords “

Inspection & Testing .
BS-7671:2011: differentiates between .
2394: Initial -verification .
- New-work .
- Additions & alterations .

Chapter - 61 : Initial - Verification . p.189
i) 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 .

 

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Test-methods :

GN-3 : Inspection& Testing .
612.2.1. - Continuity of protective-conductor(s) including . main and supplementary-equipotential-bonding.
612.2.2. - Continuity of ring-final-circuit-conductor(s)
542.4.2. - Tofacilitate measurement of the résistance of the . earthing-arrangements . meansshall be provided in an accessible-position .for disconnecting the ( Earthing-conductor) Such means may conveniently becombined with the . main-earhing-terminal . or bar . Any joint shall be capable of disconnection only by means of a tool

Earth-electrode-résistance . 612.7. . Where required.
Where the . earthing-system incorporates anearth-electrode as part of the installation . the electrode-résistance . toEarth shall be measured .
( Note ) Wherea measurement of ( R[SUP]A[/SUP] ) is not-practicable . themeasured-value of . external-earth-fault-loop-impedance may be Used .

Means of disconnection of Earthing-arrangements .

612.2.1. - Continuity of protective-conductor(s)
A continuity-test . shall be made . it is recommended thatthe test be carried-out with a supplyhaving a . no-load-voltage . between 4V . and 24V . d.c.or a.c. & a short-circuit-current ofnot less than . 200mA .

Re-cap . p.190
Testing : The testsof . Regulation(s) 612.2 to 612.6. where relevant . shall be carried-out in that order . before the installation is . Energized .
Where : theinstallation-incorporates an . Earth-Electrode . the test of . Regulation -612.7. shall also be carried-out . before theinstallation is . Energized .

If any test-indicates a failure to comply . that test & any preceding-test . theresults of which may have been-influenced . by the fault-indicated . shall be repeated after the fault has been rectified .

 

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My-point. 2394: it’s out their if we look for it.

BS-7671:2028:2011: has to state the facts .
GN-3. talks us through it . “ Answers“

Q) State :
Prerequisite-checksthat need to be applied . prior to undertaking an . Insulation-résistance-test.

i) Verify-supply is . isolated .

Dead-Test :

ii) All current-using-equipment . is disconnected.
iii) Disconnect any voltage-sensitive-equipment .
- pilotor indicator-lamps .
-voltage-sensitive-electronic-equipment . such as .
Dimmer-switches.
Touch-switches.
Delay-timers.
Electronic-starters- for fluorescent-lamps .
Emergency-lighting.
RCDs. and similar-equipment are disconnected . so that they are . Not subjected to test-voltages

 

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Bruce. still at collage .

2394: Installations should be inspected andtested . Before being put into service. “ Initial-verification “ 610.1.
2395: Atregular-intervals . therefore . “ Periodic-inspection “

Themain-reason for undertaking an . inspection and testing is to ensure that theinstallation is safe to Use .

Circuit-breaker: BS-EN-60898 . operation
• Thermal - overload .
• Magnetic - short-circuit-conditions .

Circuit-breakersrequire relatively . high-currents in order to operate . ( 3 x 32A = 96A . If ) or ( 5 x 32A = 160A . If ) B -type .
RCDs. operate in the region of - milli-amps . mA . ( 30mA ÷ 1000 = 0.03A ) RCD Earth-fault. 0.04mS

Q). What are the two-types of . Prospective-fault-current measured at the source . (Ipf ) . which needs to be recorded .
612.11. ( PFC )
i). Prospective-short-circuit-current .
ii). Prospective-earth-fault-current .
- at the origin .
- and at other-relevant-points in the installation.

Thelargest of the . two needs to be recorded .

GN-3. reminds us . p.54
The-Term. Prospective-fault-current . includes the . Prospective-short-circuit-current. & Prospective-earth-fault-current .it is the Greater of these .two-prospective-faults-currents . which should be determined . ( PSCC ) - ( PEFC )

 

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Q) the reason for undertaking a .continuity-test on the Line-conductor & circuit-protective-conductors . ofa ring-final-circuit.
Toensure that ring-final-circuit iscomplete . without interconnections .
Q) Two-other tests automatically carried outwhen undertaking the above. ↑↑ .
Polarity. ( R[SUP]1[/SUP] + R[SUP]2[/SUP] )

 

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Q) 30mA is required to havethree-tests-applied . what are they . & what currents would need to beapplied .

50% . of 30mA , 15mA . the RCD . should not trip .
100%. of 30mA , 30mA the RCD . would trip inunder . 300mS . NoteBS-EN. ◄
500%. of 30mA , or 150mA . the RCD . should trip inunder 40mS … ( 5 x 30 = 150mA ) 5 x 500% .

RCD- Testers .

GN-3: p.84
i). Should be capable of supplying full-range of test-currents . 50% . 100% . 500%. ½ . x1 . 5 x .
ii). -&-s . Test -current should be applied for . no-longer than . 2 seconds . RCD - Only
iii). Instrument to . BS-EN-61557-6 . will satisfy the above .

Re-cap. GN-3. p.58
Operationof . residual-current-device .
411.4.5.
For each of the tests . readingsshould be taken on . both positive & negative . half-cycles and the . longer-operating-time-recorded. :13:

GN-3: has reminded us . p.58
Prior to these RCD-tests .it is essential . for safety-reasons .that the earth-loop-impedance . is testedto check . the requirements have been met .

 

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My mistake .

50% . of 30mA , 15mA . the RCD . should not trip .
500%.of 30mA , the RCD . should trip in under40mS

What do we require. 2394 : reading- material
Regulations BS-7671:2008:2011:
Guidance - Note 3 .
O.S.G. - 2011 .

Q) . How are live-conductors , in a 3 -phase-circuit indentified ? A ) . Part- 5 . Table - 51 . p.116 . Identification of conductors .
Q ) . State :- the methods for selecting the correct-type , and size of the , Main-protective-bonding-conductor . ? A) .544.1. p.167 .
Q ) . State :- the methods for connecting the , Main-earthing-terminal , to Earth in electrical-installation . ? A) . 542.1.100 . p.158
Q ) . Describe in whichcase the . Electrical-Installation-Certificate is to be used. ? A) . 631.1. P.195

 

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State :
a) . Two-statutory-documentsthat have a direct- influence upon , Inspection & Testing .
b) . The legal-status of , HSE - GN-38 document on ,electrical-test-equipment for electricians .

a). Health &Safety at Work Act 1974 . Electricity at Work Regulations -1989
b). This is a , Guidance-note. & therefore cannot be . (Statutory ) Non-Statutory . ( Written-exams)

State :
The legal-status of each of the following .
a) . BS-7671:2008:2011: . A) Non-Statutory.
B) . The On-Site-Guide . A) Non-Statutory.
c) . The Electricity at Work Regulations 1989 . . Statutory

State :
a) . When an Initial-inspection & Test should becarried-out .
b) . The precautions to be taken during an ., Inspection & Test .
a) . During and on completion,before being put into service . p.189 - 610.1
b) . Avoid danger to persons, livestock and damage to property. p.189 - 610.1

Initial-Verification . p.189 - 610.1
Every-installation shall, during erection and on completion , before being put into service . be Inspected & Tested to verify . ETC.

1 down : Precautions shall be taken to , avoid danger to persons and property . and installed-equipment. during Inspected & Testing .

 

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Q ) . What is the difference between ,Basic-protection , & Fault-protection ?
- Basic-protection against . electric-shock under-fault-free-conditions. p.23 . under-normal-condition .
- Fault-protection against . electric-shockunder-single-fault-conditions . p.28 . under-fault-conditions .

Chapter - 41 . to understand these ,fundamental-principles . 411.2 . 411.3 . p.52 / 53

Q ) . Describe the methods of , Basic-protection & Fault-protection , regarding. automatic-disconnection of the supply. ( ADS ) A). 411.
Q ) . State : the difference between , Overcurrent & Fault-current . 433 . 434 .p.81 / p.83 .

Overcurrent : An overcurrent-exceeding the rated-valve , forconductors the rated-value is the current-carrying-capacity . p.32
Fault-current : A current-resulting from a fault . p.28

 

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Q ) . What : does the specification of “ BS-EN-60898 “ standsfor . A) . Appendix - 1 . p.277
Q ) . State : the maximum-disconnection-time , for an A.C. low-voltage ., final-circuit not exceeding 32A . A) . Table - 41.1. / 0.4s .
Q ) . State : the need for , initial-verification . A) . 610 . p.189
Q ) . State : the minimum-values of , insulation-résistance . A ) Table- 61 . p191
Q ) . State : requirementsfor , periodic-inspection & testing. . A) 634.1. p.196
Q ) . Describe : inwhich case the , Electrical-installation-certificate , is to be used. A) 631.1 . p.195
Q ) . After : completing an , Electrical-installation-certificate , to whomit will need , to be given a copy . A). Appendix - 6 .

Q) . 551.4.4. Portable-Generating-Sets , can be used tosupply . ?? refer . O.S.G. p 19
- Permanent-installations .
- Temporary-installations .
- Portable-equipment .

Not in the O.S.G.
When supplying ,permanent or temporary-installations .generating-sets . can be :

- The only means ofsupply .
- Means of supplywhen , the public-supply is not available - ( Standby-supply )
- Supply inparallel with the public-supply .

 

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Inspection & Testing . Re-cap

C1 : Danger-present. Risk of injury.Immediate-remedial-action-required .
C2 : Potentially-dangerous -urgent-remedial-action-required.
C3 : Improvement-recommended .

The recording of either a . C1 or C2 - observation in the. ( EICR ) would result in an . unsatisfactory-outcome .
In other words , the installation would not bedeemed-compliant to . BS-7671:2008: (2011) in this case the recipient of the report ,must take action , either immediately or urgently, in accordance with the .observation made .

By highlighting-exceptions to a ,satisfactory-installation , the ( EICR ) rapidly draws-attention to the issues and theappropriate-response to them . if an issue is recorded it should be dealt with. ( Note : the EICR .is covered by . regulation - 631.2. 631.4. 631.5 . 634.1 . )

Certification & Reporting :
631.2 . p.195 .
Upon-completion of the . periodic-inspection & testingof an existing-installation , an Electrical-Installation-Condition-Report ,based on the model given in Appendix - 6 .
shall be provided.Such-documentation shall include-details of the extent of the installation .& limitations of the . inspection & testing . covered by the Report . together withrecords of inspection , the results of testing and a . recommendation for theinterval-unit the . next-periodic-inspection .

Certification & Reporting :
631.4 . p196
Electrical-Installation-Certificates ,Electrical-Installation-Condition-Reports . &Minor-Electrical-Installation-Work-Certificates . shall be compiled and signedor otherwise-authenticated by a . competent-person or persons .

Certification & Reporting :
631.5 . p196
Electrical-Installation-Certificates ,Electrical-Installation-Condition-Reports . &Minor-Electrical-Installation-Work-Certificates . may be produced in anydurable medium , including written , & electronic-media . Regardless of themedia used for . original-certificates . reports or their-copies ,their-authenticity and integrity shallbe verified by a reliable-process or method . The process or method shall also, verify that any copy is a true-copy of the . original .

Periodic-Inspection & Testing :
634.1 . p196
Following the periodic-inspection & testing describedin . Chapter - 62 , an Electrical-Installation-Condition-Report , together with schedules of inspection , & schedules of test-results ,shall be given by the person carrying out the inspection , or aperson-authorized to act on their-behalf , to the person-ordering theinspection. These-schedules shall be based on the models . given in Appendix -6 . The schedules of test-results , shall record the results , of theappropriate-tests required of . Chapter - 61 .

 

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Overlooked . Q) . State : examples of installations within the scope of BS-7671:2008:2011: A) . 110.1. Regulations apply to the design, erection and verification, of electrical-installations , such as thoseof : Etc i) . residual-premises. ii) . commercial-premises . iii) . public-premises . v) . industrial-premises. incorporating - Amendment - No . 1 xv) . medical-locations xvi) . operating and maintenance-gangways . Q) . State : the relationship of , BS-7671:2008:2011: to statutory-regulations . A) . 114. 115 . 113 - Equipment : p.15 The Regulations - apply to items of , electrical-equipment only so far as, selection & application of the equipment in the installation are concerned . The Regulations - do not deal with requirements for the construction of assemblies of , electrical-equipment, which are required to comply with appropriate-standards .

- - - Updated - - -

Overlooked .

Q) . State : examples of installations within the scope ofBS-7671:2008:2011: A) . 110.1.

Regulations apply to the design, erection and verification, of electrical-installations , such as thoseof : Etc
i) . residual-premises .
ii) . commercial-premises .
iii) . public-premises.
v) . industrial-premises.

incorporating - Amendment - No . 1
xv) . medical-locations
xvi) . operating and maintenance-gangways .

Q) . State : the relationship of , BS-7671:2008:2011: to statutory-regulations . A) . 114. 115 .

113 - Equipment: p.15
The Regulations - apply to items of , electrical-equipment only so far as ,selection & application of the equipment in the installation are concerned .
The Regulations - do not deal with requirements for the construction of assemblies of , electrical-equipment, which are required to comply with appropriate-standards .

 

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Q) . Define : the meaning of , Earth-fault-loop-impedance.
p.26 . Earth-fault-loop-impedance , The impedance of theearth-fault-current-loop , and ending at the point of earth-fault , Thisimpedance is denoted by the symbol ( Zs )

( PEFC ) shown by calculation .
Is measured between, Line-conductor & Earth , at theorigin . 230V / 0.1Ω = 2300A . or 2.3kA . as it should be recorded on Certificate . Uo / Ze
.
( PFC ) prospective-fault-current .
612.11. ( PEFC ) shall be measured . at the Origin . Domestic-installations .

GN-3 : p.83 . Earth-fault-loop-impedance-testers .
To minimise , electric-shock-hazard , from the potentialof the , protective-conductor , the test-duration should be within safe-limits . This meansthat the instrument should cut , off thetest-current after , 40mS

Known your test-instrument : GN-3 . BS-EN-61557-3. Part - 3 . Earth-fault-loop-impedance-tester.

Circuit-loop-impedance :
612.9. Whereprotective-measures , are used which require a knowledge of , earth-fault-loop-impedance , the relevant-impedance .shall be measured . Etc

 

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Safely-isolate-electricity :
Safely-isolate-electrical-circuit(s) : Securing the device in the “ OFF “ position .
Isolate-devices-safely :

State : Q ) . state the reasons for carrying out . Safe-Isolation.
Q) . State : the requirements of the , Electricity atWork-Regulations 1989 , for safe-inspection ofelectrical-systems & equipment .
Safe-Isolation . Low-voltage-installation(s)

Statutory-requirements . The most important- Statutory-requirement, concerning work carried out , On or Near electrical-installation(s) is the . Electricity at Work-Regulations - 1989 . These Regulation(s) within ( EaWR ) Particular - relevance to ( Safe-isolation ) are number(s) are 12) . Means of cutting off the supply , and forisolation .13) . ( Precautions for work on , equipment made Dead ) Regulation - 12(1) (b) States : that where necessary to ( prevent-danger ) suitable means shall be available for the , isolation of any electrical-equipment , where isolation means the disconnection and separation of the electrical-equipment from ( Every source in sucha way that the disconnection and separation is secure ) (2)) refers , The Memorandumof Guidance on the , Electricity at WorkRegulation(s) - 1989 . HS(R) 25) Heathand Safety Executive , advises withreference to Regulation - 12 (1) above that isolation is the process ofensuring that , that the supply to all , or a particular-part of an installation-remains -switched OFF , and that inadvertent-reconnection is prevented . Preventing-inadvertent-reconnection is covered in Regulation- ( 13 ) Electricity at Work Regulation(s) - 1989 . ( Which requires that )
Adequate-precautions , shall be taken to prevent electrical-equipment , which has been made ( Dead ) in order to prevent-danger , while-work isbeing-carried-out On or Near that equipment , from becoming-electrically -charged during that work , if dangermay-thereby-arise .

Regulation - ( 13 ) in HR(R) 25 . highlights the ( Need to lock-OFF ) Switching-device , being-used to provide-isolation , or whereisolation has been , achieved by a ( Fuse ) by their-removal and retention in a safe-place-during the isolated-period .
132.15. Isolation and Switching . relevance in terms of , safe-isolation . Regulation - 132.15.1. refer . Regulation - group . 537.3. switching OFF for mechanical-maintenance . Table - 53.2. summarises the suitability ofparticular-protective , Isolation & Switching-devices .

 

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This could be my - computer , or scrambled on the download . Sorry about-that

Safely-isolate-electricity :
Safely-isolate-electrical-circuit(s) : Securing the device in the “ OFF “ position .
Isolate-devices-safely :

State : Q ) . state the reasons for carrying out . Safe-Isolation.
Q) . State : therequirements of the , Electricity at Work-Regulations 1989 ,for safe-inspection of electrical-systems & equipment .

Safe-Isolation . Low-voltage-installation(s)

Statutory-requirements .
The most important- Statutory-requirement ,concerning work carried out , On or Near electrical-installation(s) is the . Electricity at Work-Regulations - 1989 . These
Regulation(s) within ( EaWR )

Particular - relevance to ( Safe-isolation) are number(s) are
12) . Means ofcutting off the supply , and for isolation .
13) . ( Precautions forwork on , equipment made Dead )

Regulation - 12(1) (b) States : that where necessary to ( prevent-danger ) suitable means shall be available for the , isolation of any electrical-equipment , where isolation means the disconnection and separation of the electrical-equipment from ( Every source in sucha way that the disconnection and separation is secure )
(2)) refers , The Memorandum of Guidance on the , Electricity at Work Regulation(s)- 1989 . HS(R) 25) Heath and Safety Executive , advises with reference toRegulation - 12 (1) above that isolation is the process ofensuring that , that the supply to all , or a particular-part of an installation-remains -switched OFF , and that inadvertent-reconnection is prevented .

Preventing-inadvertent-reconnection is covered in Regulation- ( 13 ) Electricity at Work Regulation(s) - 1989 . ( Which requires that )
Adequate-precautions , shall be taken to prevent electrical-equipment , which has been made ( Dead ) in order to prevent-danger , while-work isbeing-carried-out On or Near that equipment , from becoming-electrically -charged during that work , if dangermay-thereby-arise .

Regulation - ( 13 ) in HR(R) 25 . highlights the ( Need to lock-OFF ) Switching-device , being-used to provide-isolation , or whereisolation has been , achieved by a ( Fuse ) by their-removal and retention in a safe-place-during the isolated-period .


132.15. Isolationand Switching . relevance in terms of ,safe-isolation .
Regulation -132.15.1. refer .

Regulation - group . 537.3. switching OFF for mechanical-maintenance .
Table - 53.2. summarises the suitability of particular-protective , Isolation & Switching-devices .

 

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PVC - cables , Old to New . Why does this come up in Exams ?? 16[SUP]th[/SUP] Edition . The components of a wiring-system , including-cables and wiring-enclosures , shall beinstalled or handled-only at temperatures within the limits stated in the relevant-product-specification or asrecommended by the manufacturer . Regulations : PVC - cables , At lowtemperature PVC - cables insulation canbecome brittle when handled . 522.1.2. 2008 & 2011 . p.123. Wiring-system-components , including cables & wiring-accessories , shall only be installed or handled at temperatures within the limits stated in the relevant-product-specification or as given by the manufacturer . PVC - cables : must not beinstalled when theambient-temperature is ( 0°C ) refer IET - Regulation . 522.1.2.

- - - Updated - - -

PVC - cables , Old to New . Why does this come up in Exams ??

16[SUP]th[/SUP] Edition . The components of a wiring-system , including-cables and wiring-enclosures , shall beinstalled or handled-only at temperatures within the limits stated in the relevant-product-specification or asrecommended by the manufacturer .


Regulations :
PVC - cables , At low temperature PVC - cables insulation can become brittlewhen handled .

522.1.2. 2008 & 2011 . p.123.
Wiring-system-components , including cables & wiring-accessories, shall only be installed or handled at temperatures within the limits stated in the relevant-product-specification or as given by the manufacturer .

PVC - cables : must not be installed when the ambient-temperature is ( 0°C ) refer IET - Regulation . 522.1.2.

 

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Doing some calculations for conduit . re-cap
Cable capacities of Conduit. Appendix E . p.133 - O.S.G.

Six 2.5mm[SUP]2 [/SUP] , PVC -insulated-cables , are to be run in a conduit containing two bends between boxes , 10mm apart. determine the minimum-size of conduit to containthese cables .

The factor for , one 2.5mm[SUP]2 [/SUP] cable = 30
The sum of the cable-factor = 6 x 30 = 180.

Next : Table - E 4 . p.136 . 10m → 2 x bends - 25mm = 260 .
Table - E 4. 20mm conduit containing 2 x bends .only has a factor of 141 . Whichis less than . 180 .
Therefore : 25mm[SUP] [/SUP] conduit is theminimum-size to contain these-cables .

Ten 1.0mm[SUP]2 [/SUP] , PVC - insulated-cables are to be drawn into conduit , which is 6m long between-boxes and contain one-bend . 4.0mm[SUP]2 [/SUP] PVC -insulated-CPC . is also included .

Determine the minimum-size of conduit to contain these-conductors . Table - E3 . long straight runs Over 3m ,
Cf) One 1.0mm[SUP]2 [/SUP] cable = 16
Cf) One 4.0mm[SUP]2 [/SUP] cable = 43
( 10 x 16 ) + ( 1 x 43 ) = 203 . 160 + 43 = 203

Table - E 4 . 20mm conduit , 6m 1 x bend has a factor of 233.
16mm conduit . containing 1 x bend has a factor of 143. which is less than 203 ,
The sum of thecable-factors and , therefore .20mm conduit is the , minimum-size to contain these cables .

Table - E 4 . O.S.G. reminds us . only gives factors for conduits up to 32mm, in diameter, which would indicate that conduits larger than thisare not in , frequent or common-use .

O.S.G. bottom-page: Additional-factors:
38mm , diameter use 1.4 x ( 32mm factor )
50mm , diameter use 2.6 x ( 32mm factor )
63mm , diameter use 4.2 x ( 32mm factor )

When acable-enclosure-greater than , 32mm is required because of the number or size of the conductors , it is generally more economical and convenient to use trunking .

Where the wring-system passes through-elements , ofbuilding-construction such as floors . walls . any damage must be made-good
p.132 . Fire-safety: Regulation - 527.2. 527.2.2. Wiring-system such as aconduit-system . Etc

 

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Re-minder : Human-errors , being careless and notpaying-attention to what you should be doing at work .
A Hazard : is something with the Potential , to cause harm .
Risk : is thelikehood of harm actually being-done . Why do we do aRisk-Assessment .

2394 : reading- material
Regulations . is reminding us.
GN-3 . is reminding us .
O.S.G. is reminding us .

p.89 . O.S.G. - Guidance on Initial-Testing of Installation(s) .

10.1. p.89 . Safety and Equipment .
HSR25 , EWR , Regulation - 14 .

Electrical testing involves-danger.
The Electricity atWork Regulations -1989 . States : that working on Live-conductors is permissible ( Provided ) that it is reasonable in all thecircumstances for the work to be carriedout and that , suitable-precautions aretaken to prevent-injury .

While live-testing may be required in order to find the ( Fault) Live-repair-work must ( Not ) be carried-out , The individual-circuit or item of equipment , must first be isolated .

Regulations . p.29. Isolation . A function intended to cut ( OFF ) for reasons of safety the supply from all .
GN-3 reminds us . Thecircuit must be Isolated using a “ Safe-Isolation-procedure “

Live-testing of electrical-installationsis , therefore , reasonable as it is a , recognised-method of assessing the suitability and safety of an electrical-installation: suitable-precautions must be taken by, employing the correct-test-equipment , andsuitable-personal-protective-equipment .

O.S.G. reinforces this : Although Live-testing and diagnosis for fault-finding may bejustifiable , there could be ( No - Justification ) for any subsequent-repair-work to becarried-out-live .

610.1. : O.S.G.
It is the Test-operative’s-duty toensure their own-safety . and thesafety of Others. whilst working through Test-procedures. 612.1.

612.1. Re-minder .
i) . knowledge and experience of thecorrect-application and use of theTest-Instrumentation , leads , probes and accessories ( isof the greatest-importance )
ii) . checking thatthe Test-instrumentation is made in accordance with the appropriate-safety-standards such as , BS-EN-61243-3 . for two-pole-voltage-detectors and BS-EN-61010 or BS-EN-61557(?) for instruments .
iii) . checking before each use that all leads , probes . accessories( Including all devices such as crocodile-clips used to attach to conductors ) Etc.

GN-38: iv) observing the safety-measures andprocedures set out in , HSE - Guidance - Note GS-38 , for all instruments. leads , probes and accessories . Sometest-instruments-manufactures advise thattheir instruments be used in conjunction with ( Fused-test-leads and probes )
Others-advise theuse of non-fused-leadsand probes when the , instrument has in-built-electrical-protection , butit should be noted that such , electrical-protection does ( Not ) extend tothe ( Probes& Leads )

So : TheTest-instruments and Test-leadsused by the electrician for testing anelectrical-installation , must meet all requirements of the relevant-regulations .

Test-Instrument-Leads .

British-standards :
Heath & SafetyExecutive .guidance relating to , Test-Instrument-Leads .
When using , electrical-test-equipment , & to meet therequirements of the , Electricity atWork Regulations - 1989 .

The Electricity atWork Regulations - 1989 . require those in control of ( All ) or ( Part) of an electrical-system , to ensure it is safe to use & maintained .

Heath & Safety Executive . guidance relating to ,Test-Instrument-Leads .

It is important that , ( Fused-test-instrument-leads) are used where there is apotential-risk of a fault-currentpassing through the , test- Instrument-Leads that could cause-damage to the instrument .

 

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612.2.2. Continuity of ring-final-circuit-conductors .

Test :
O.S.G. p.92 . A Three-step is required to verify the continuity of the ,Line , Neutral , protective-conductors & correct-wiring of every , ring-final-circuit . Etc .
GN- 3 . p. 35 . A Three-step is required to verify the continuity ofthe , Line , Neutral , protective-conductors & correct-wiring of every , ring-final-circuit . Etc .

Step 1 : Ohmmeterconnected to ( L[SUP]1[/SUP] & L[SUP]2[/SUP] ) This gives a value for ( Little r[SUP]1[/SUP] )
Step 1 : Ohmmeterconnected to ( N[SUP]1[/SUP] & N[SUP]2[/SUP] ) This gives a value for ( Little r[SUP]n[/SUP] )
Step 1 : Ohmmeterconnected to ( CPC[SUP]1[/SUP] & CPC[SUP]2[/SUP] ) This gives a value for ( Little r[SUP]2[/SUP] )

Step 2 : Line & Neutral , ateach-socket-outlet
Step 3 : Line & Earth , ateach-socket-outlet . Circuit-protective-conductor . ( R[SUP]1[/SUP] +R[SUP]2[/SUP] )

As a check ( R[SUP]1[/SUP] +R[SUP]2[/SUP] ) value should equal ( r[SUP]1[/SUP] + r[SUP]2[/SUP] ) / 4

Refer to GN-3 .

 

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2392-10as its been extended . old notes to help you 2009 / 10
2392-10Course unit 101 ( 2.1 )

1: Which oneof the following Senses is Not used during the Initial Inspection and Testingprocess ?
(a ) Sight ( b ) Touch ( c ) Taste ( d ) Smell

2: Duringthe initial inspection and testing sight would indicate a fault such as ?
(a ) Overheating ( b ) Equipment Overheating ( c ) Vibration of transformer cover ( d ) DamageEquipment

3: Humansenses are used mainly during the ?
(a ) Inspectionprocess ( b ) Testing process ( c ) Certification process ( d ) Safe isolation procedures

4: Touchwould indicate a fault due to ?
(a ) Incorrect cable size ( b ) Arcing due to loose connections ( c ) Incorrect labelling ( d ) Poor fixings of accessories

5: HumanSenses ?
(a ) Are anintegral part of the inspection process ( b ) Should not be used to detect faults’
(c ) Are useful for live circuits only ( d ) Should be used one at a time

unit101 ( 2.2 )
1: An Initial Inspection should be carriedout ?
(a ) After the erection process ( b ) During the Erection process and before Energising
(c ) Before the erection process ( d ) Approved by the Heath and SafetyExecutive

2: All equipment and materials’ should be ?
(a ) To therelevant British Standard or Equivalent
(b ) To a standard agreed by the personordering the work
(c ) To standards set out by the local authority building control
(d ) Approved by the Heath and Safety Executive

3: Which of the following is not an itemfor Inspection ?
(a ) Connection of conductors ( b ) Routing of cables ( c ) Selection and erection to maximise fire
(d ) Isolation and switching devices

4: Labelling of Protective devices , switches andterminals’ ?
(a ) Is not important ( b ) Is essential ( c ) Should all be the same colour labels ( d ) Is only required for MCBs

5: Detailed requirements for selection and erection is given in BS-7671 : 2008
(a ) Chapter 32 ( b ) Chapter 52 ( c ) 41 ( d) 11

 

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2392-10 Course unit 101 ( 2.3 )
1 : TheElectricity at Work Regulations came out in ? ( a ) 1974 ( b ) 1980 ( c ) 1989 ( d ) 1996
3 : Adverseor hazardous environments are coved in Electricity at Work Regulation ? ( a ) 4 ( b ) 6 ( c ) 8 ( d ) 10
4 : Regulation 8 of the Electricity at Work Regulations is concerned with ? (a ) Insulation , protection and placing of conductors (b ) Strength and capability of electrical equipment ( c ) Earthingor other suitable precautions ( d ) Connections
5 : Regulation 11 of the Electricity at Work Regulations is concernedwith ? ( a ) Allows protective devices to be shorted out during test ( b ) Allows fuses to be shorted outduring test ( c ) Does not allowprotective devices to be shorted out during test (d ) Allows MCBs to be shorted out during test
6 : Regulation 16 of the EAWR states that noperson shall be engaged in any work Activity requiring knowledge or experience unless they are ? ( a ) Incompetent ( b ) Unsupervised ( c ) Competentor Supervised (d ) Self-employed
7 : Working on orNear Live Conductors’ ? ( a ) Is allowedoutside working hours ( b ) Is not allowed under any circumstances (c ) Is allowed if itis unreasonable for them to be dead ( d ) Is not allowed unless rubber gloves are worn (try BQ )
8 : Regulation 13 of the EAWR is referring to ? ( a ) Workingspace , access and lighting (b ) Safe isolationprocedures (c ) Integrity of referenced conductors ( d ) Persons on whom duties are imposed

 

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1 : Voltage probes , voltage indicators and instruments test leads must complywith ? ( GS38 )

2 : Continuity testers indicate values off ? ( Ohms)

3 : Insulation testers indicate values off ? ( Megohms)

4 : Prospective Fault Current is measured in ? ( kA) ( PFC )

5: The Recommended sequence of test isgiven in BS-7671 : 2008 ( PART 6 ) ( you may have to use this on your test ) 1 : 612.2 ( 2 : 612.2 .2 ( 3 : 612.2.3 ( 4 : 612.6 “regs out “

6: The last three test to be carried outare ? 612.12 ( 612.13 ( 612.14 ) “regs out “

7: Circuit Protective Conductors’connected ?
( a ) Gas and Water services to main earthterminal
( b ) The main earth terminal to consumerunit
( c ) Exposedconductive parts to the main earth terminal
( d ) Supplementary bonding to main earthterminal

8: Main bonding conductors’ for Gas andWater etc , are tested for continuity with a continuity tester
(a ) End to End ( b ) Through the metalpipe ( c ) Endto end after disconnecting one end from the bonding clamp
(d ) At one End and the metal pipe

9: When testing a final circuitcontinuity ( R1 + R2 ) the circuit isswitched on and off at the control switch to Verify ?
(a ) There is a supply present ( b ) Theswitch operates correctly ( c ) The polarity iscorrect
(d ) There are no loose connections

10: Maximum permissible test values for final circuit loop impedance can be foundin ? “regs out “
(a ) BS-7671 : 2008 ( b ) IEE Guidance Note 3 table 2D ( c ) Electricity at Work Regulations1989 ( d ) HSE GS38
o.s.g
11: Before carrying out a continuity test the instrument should be ?
(a ) Face upwards ( b ) Nulled to eliminate test leadresistance ( c ) Switched off ( d ) Set on the Kilohms range

12: Prior to carrying out insulation resistance testing the client needs to beConsulted for ?
(a ) Amount of time required to complete the test ( b ) Supervising the test
(c ) Ensuring test voltages are no danger toequipment , persons or livestock ( d ) Extra help if required

13: During the safe isolation procedure GS-38 Approved Test Lamps or Voltageindicators should be ?
(a ) Tested at twice their rated voltage ( b ) Tested before and after use on knownsupply proving unit a must

14: An RCD when tested at 50% of its trip rating should ?
(a ) Not trip a must ( b ) Trip within 300mS ( c ) Trip within 40mS ( d ) Trip within 100mS

15: An RCD when tested at 100% ( x1 times ) of its trip rating should ? ( PS - BS-EN ) ◄◄
(a ) Not trip ( b ) Trip within 300mS a must ( c ) Trip within 40mS ( d ) Trip within 100mS

16: An RCD when tested at 500% ( x5 times ) of its trip rating should ?
(a ) Not trip ( b ) Trip within 300mS ( c ) Trip within 40mS a must ( d ) Trip within 100mS

 

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Measurementusing Earth Electrode Test Instrument . ( 3 x Rods )
Threemeasurements are taken : 79ohms+ 85ohms+ 80ohms . a must
Addedall together : 244Ω . 244ohms / 3 = 81.33ohms

 

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Unit101 ( 1.2 )

( 1) Regulation 610.2 of BS-7671 : 2008 requires Information prior toan Inspection and test is made available to the ?
Answer: Shall bemade available to the person or persons carrying out the Inspection and testing

( 2) The results of the Assessment of an Electrical Installation with regards toprotection for Safety shall be made Available to the ?
Answer: Inspectorprior to carrying out the Inspection and test

( 3) Which of the following is Not a fundamentalprinciple with regards to protection for Safety ?

Answer: ( a ) protection against ingress of water : ( b ) protection against thermal effects :
(c ) protection against faultcurrent ( d ) protection against voltage disturbances

( 4) Which of the following is Afundamental principle with regards to protection for Safety ?
Answer: ( a ) Measure’s against the ingress of dust ( b ) Measure’sagainst the Electromagnetic disturbances
(c ) Measure’s against damage toequipment ( d ) Measure’s against theingress of water

( 5) The results of the Assessment of an Electrical Installation with regards togeneral Characteristics shall be made Available to the ?
Answer: ( a ) Tenant of the building ( b ) Owner of the building
(c ) Electrician carrying out any sub-contractors work ( d ) Inspector prior to carrying out an inspection and test

( 6) Which one of the following is Not a generalCharacteristic of an Electrical installation ?
Answer: ( a ) Supplies for SafetyServices ( b ) Number offinal circuits ( c ) Maximumdemand and diversity ( d ) Type of Earthing arrangement

( 7 ) Which one of the following is a generalCharacteristic of an Electrical installation ?
(a ) Number and type of live Conductors ( b ) Type of wiring system ( c )Routing of cables ( d ) Number ofConsumer units or distribution boards within the installation

(8 ) Information such as diagrams and schedules shall be made available to the ?
(a ) Architect during the design stage of a building ( b ) Electrician on completion of anElectrical installation
(c ) the person ordering the work ( d ) Theinspector prior to carrying out an inspection and test

(9 ) Which one of the following is Not required to be given on a diagram orschedule ?
(a ) Place in or near to the relevant distribution board ( b ) Given to the person ordering the work
(c ) Placed at the origin of the supply ( d )Given to the tenant

(10 ) A durable copy of a distribution board schedule shall be ?
(a ) Place inor near to the relevant distribution board ( b) Given to the person ordering the work
( c ) Placed atthe origin of the supply ( d ) Given to the tenant

 

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Unit101 1.3
( 1) The H.A.S.A.W Act came out in ? ( a ) 1974

( 2) Regulation 16 of the Electrical at Work Regulations 1989 is concernedwith ?
Competence

( 3) The Electricity at Work Regulations1989 is ? p - 241
( b) Statutory

( 4) The H.A.S.A.W Act 1974 appliesto ? ( d ) Employees , Employers & Self- employed

( 5) Part P of the Building Regulations applies to ?
( d) IEE guidance booklet

( 6) The 17[SUP]th[/SUP] Edition Wiring Regulations BS-7671 : 2008 is ?
(c ) Non Statutory

( 7) Test leads to GS38 should have ?
( b) 2mm exposed probe , Non fused lead or current limiting and finger barriers. 2mm to 4mm exposedprobe
NOTE . At this point.. 2mm - is for live-testing . 4mm - dead- testing . ◄◄◄◄ 2392 / 2394 .

Non-fused-leads.
Fused-Leads

( 8 ) The Electrical Safety , Quality and Continuity Regulations place a LegalObligation on ?
( c ) The Supplier

 

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2392-10

(1 ) During Erection and completion everyInstallation shall be Inspected and tested to Unity that ?
( b ) The requirements of the Regulations have been met

(2 ) During Inspection and testingPrecautions shall be taken in order to ensure supplies to ?
( d) Nodanger to person or damage to property and Equipment

(3 ) Once the initial verification has been completed an Electrical InstallationCertificate and Schedule of Inspection and test results ?
( a ) Is given to the person ordering the work

(4 ) Any defects or Omissions revealedduring initial Inspection and testing should be made good ?
( b) Before the Certificate isissued

(5 ) The Initial Verification shall becarried out by ?
( c) ACompetent person

(6 ) If an Additional alternative hasbeen carried out it must Not ?
( b) Increase the Electrical consumption

(7 ) The chapter in BS-7671 referring toInitial Verification is
( d ) 61

 

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Remember to covert to BS-7671:2008:2011: This will be the last time on 2392-10 . closed-book .

2392-10 ( Minor Electrical Installation Works Certificate p/336 )

(1)Q) An ElectricalInstallation Certificate is Issued for ? ( p/333
A)Initial Certification of a New Installation ,

(2)Q) An Additionor Alteration to an Existing Installation where New Circuit’s has beenInstalled Requires , ?
A)An ElectricalInstallation Certificate ,

(3)Q) Once an Electrical Installation Certificate has been Completed the Original should be ? A) Given to the Person Ordering the Work ,

(4)Q) The Electrical Installation Certificate should be Singed or Authenticated bythe ?
A) Competent Person or Person(s)

(5) Q) The Recommended Time Interval . beforethe First Periodic Inspection can be Obtained from ?
A) IEEGuidance Note 3 ◄ p/334 (7) - ( p/339 – Periodic Inspection Report )

(6)Q) A Minor Electrical Installation Works Certificate is Used for an Addition orAlteration that ?
A) DoesNot Include the Provision of a New Circuit ,

(7) Q) The Replacement of Equipment such asSocket-Outlet’s and Ceiling Rose Requires ?
A) A Minor Electrical Installation WorksCertificate ,

(8) Q) Minor Works Inspecting & Testingshould always be Carried Out ?
A) Regardless of the Extent of the Work ,

Unit101 ( 1.2 )

(1)Q) Regulation 610.2 of BS-7671:2008 , Requires Information Prior to anInspection & Test is made Available to the ?
A)Shall be Made Available to the Person or Person(s) Carrying out the Inspection& Testing , ( 2392-10 ↔ Person )

(2)Q) The Results of the Assessment of an Electrical Installation with Regards to Protection for Safety shallbe Made Available to the , ?
A) Inspector Prior to Carrying out theInspection & Test ,

(3) Q) Which of the Following is “ Not“ Fundamental Principle “ withRegards to Protection for Safety , ?
A) Protection Against Ingress of Water,

(4) Q) Which of the Following is a “ FundamentalPrinciple “ with Regards to Protection for Safety , ?
A)Measure’s Against the Electromagnetic Disturbances ,

(5 ) The results of the Assessment of an Electrical Installation with regards togeneral Characteristics shall be made Available to the ?
Inspector prior to carrying out aninspection and test

(6 ) Which one of the following is Not a general Characteristic of an Electricalinstallation ?
Number of final circuits

(7 ) Which one of the following is a general Characteristic of an Electricalinstallation ?
Number and type of live Conductors

(8 ) Information such as diagrams and schedules shall be made available to the ?
The inspector prior to carrying out aninspection and test

(10 ) A durable copy of a distribution board schedule shall be ?
Place in or near to the relevantdistribution board

 

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2392 / 2394: An Overview

Question: Instrument for Calibration .
TheUser . should ask to be ( Advised ) if it was found to be ( Inaccurate )Calibration certificate when returned . Do We .

BS-EN-61557consists of a number of ( Parts ) All parts .
Part Number - Title :
BS-EN-61557– Part - 1 )General requirements .
BS-EN-61557– Part - 2 )Insulation résistance . The fundamental reason behind Insulation is to protectuser against Electric Shock .
BS-EN-61557– Part - 3 )Earth fault loop impedance tester .
BS-EN-61557– Part - 4 )Low-résistance – ( Résistance of each Earth connection & equipotentialbonding )
BS-EN-61557– Part - 6 )Effectiveness of residual current devices ( RCD ) TN - . TT – systems
BS-EN-61557– Part - 7 )Phase sequence .

Regulations: Inspection . Testing Certification
Two-types.

Initial Verification .

Verification: is required for “ New-work “ & Alterations &Additions . ( EIC ) Certification .
Mustbe accompanied by a . Schedule of testresults & Schedule of inspections .

Periodic Inspection & Testing .
Isrequired for “ Existing installation(s) “ ( EICR )
Mustbe accompanied by a . Schedule of testresults & Schedule of inspections .

 

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Earth-fault-loop-impedance. ( Zs ) - Circuit-loop-impedance .
Why ! . This is essential for checkingthat , protective-devices operating in the required-time .

Prospective-fault-current.
Why ! . A test to measure the , highest-value of Either theprospective-short-circuit-current , or prospective-earth-fault-current at the origin , & other relevant-points within the variation .

 

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Carry out tests on , Earth-electrode(s) to ensure that their résistance is low enough to allow-fault-currents to flow-safety to Earth .

p.26 . Earth-electrode-résistance : the résistance of anearth-electrode to Earth .
p.26 . Earth-electrode : Conductive-part, which may be embedded in the soil orin a specific-conductive-medium , e.g. concrete , coke , in electrical-contact with the Earth .
TT - system : the consumer must provide their own connection to Earth . by installing asuitable earth-electrode local to the installation .

p.11 . O.S.G. 1.1. TT - system
TT - Arrangement , 21Ω is theusual-stated-maximum-résistance , ofthe distributor’s earth-electrode at thesupple-transformer . ↔ ( 1 )
The résistance of theconsumer’s-installation-earth-electrode , should be as low as practicable and a value-exceeding 200Ω may notbe stable . ↔ ( 2 )

Calculations for determining touch-voltage is ( Ze ) the rated ( mA ) of an RCD . RCD - 100mA ?
TT - system . 200Ω , 200Ω x 100mA ÷ 1000 = 20V

50V / 0.03A = 1666. 6666 . 1667Ω
50V / 0.1A = 500Ω

p.32 . Protective- equipotential-bonding: this is equipotential-bonding for the purpose of safety .

 

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Inspection & Testing :
The testing of an installation implies the use of instruments to obtain-readings .
Inspection : is necessary to make a visual-inspection ofthe installation . All existing-installations . should beperiodically-inspected & tested to ensure that they are safe & meet theRegulations - 610 , to 634 ,

Visual-inspection :
The installation must be visually-inspected before testing begins , visual-inspection is to confirm that allequipment & accessories are undamaged an comply with the relevant British-standards , & European-standards , and that theinstallation has been securely and correctly-erected .

 

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Useful-junk:

Wordused in the Trade . “ Dead “ Tests / Testing

Electricity at Work - Regulations 1989 . :gettree:

Dead ( as used inRegulations 13 / 14 )

The term “ Dead “ is not defined in the Regulations so it takes it’s , Ordinary-meaning . Thusin the context of the Regulations , for a conductor to be “ Dead “ meansthat it is neither , “ Live “ nor “ Charged “

 

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Electricity at Work - Regulations 1989 .

Fires of an , Electrical-Origin .

Firesmay be started by , electricity in a number of ways , the principal-mechanisms are:

- Overheating of cables and electrical-equipment due to ,overloading of conductors .
- Leakage-currents due to poor or inadequate-insulation .
- Overheating of flammable-materials placed toclose to , electrical-equipment , which is otherwise-operating-normally .

 

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Inspection & Testing of Electrical-installation(s)

Requirements: documentationis produced for all Installations - 132.13. “ Defined “ Every electrical-installation shall beprovided with appropriate-documentation

- Initial-Verification . New-installations . addition or alteration to an installation, Etc .
- Periodic-inspection , Existing-installation(s)


Existing-installation(s)

415.2. Additional - protection : Supplementary-equipotential-bonding.
Note 1 : Supplementary-equipotential-bonding, is considered as an , Addition to fault-protection . “ Defined “ in it’sday , Still out there

415.2.2.
Wheredoubt exists regarding the effectiveness of supplementary-equipotential-bonding , it shall be confirmed that the, résistance ( R ) between ,simultaneously-accessible , exposed-conductive-parts , & extraneous-conductive-parts , fulfils thefollowing-condition .

Where an RCD .is installed to protect the circuit the calculation to find out if , supplementary-bonding is required .

R = 50V / IΔn .

IΔn ) is the operating-current of theRCD . if it is a , 30mA - device . the calculation is as follows . ( R = 50V / 0.03A , R = 1666Ω ) Table- 41.5 30mA - 1667Ω

Where (Ia ) is the operating-current in Amperes of the protective-device for RCDs . replaced by ( IΔn ) 0.03A

 

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Ring-final-circuit: Test .

2392-10 , purpose of this test is to ensurethat . ??

- Cables form a complete Ring . Complete-Loop .
- No-interconnections.
- Polarity is correct . ( Polarity by continuity-method )
- When this test is carried-out-correctly it also gives , ( R[SUP]1[/SUP] + R[SUP]2[/SUP] ) value of the Ring-final-circuit .
►Existing-installations , Identifies-Spurs .

We have Two - 2.5mm[SUP]2[/SUP] cables wired in parallel . Regulation - 433.4.

p.83 433.4. Overload protection ofconductors in parallel.
Wherea single-protective-device protects ( Two or more conductors in parallel ) thereshall be no branch-circuits or devices for isolation , or switching in theparallel-conductors .

This Regulation , does not-preclude the use of , ring-final-circuits, with or without spur-connections .

Wheremore than one . ring-final-circuit isgetting installed . bareback the two - CPCs & twist themtogether . ring complete . Insulating-tapecomes off

 

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Wherethe Question ask , “ explain with the aid of a diagram “ then a diagram & a written-explanation is required .

Q) Test-instrument used for working onelectrical-systems should . ?
a) be less than 10 years old .
b) Have non-insulated test-probes .
c) Have insulated test-probes .
c/ A ) To protect the user from electrical-shock ,whilst using the instrument . handling-probes.

Q) When is ( Live-working-permissible )
a) When the person-carrying out the work is a competent-person .
b) When it is unreasonable in all-circumstances for theequipment to be made dead & suitable precautions are taken .
c) When the means of isolation cannot be identified .
d) When the person working on the equipment is wearingrubber-gloves .
b/ A ) This is a requirement under , regulation - 14 , EAWR Regulations . However . it does not mean that , Live-working isthen “ Safe “

Chapter- 41 . Protection against Electric-shock .

Why . do we have , Additional-protection ?

Q) The lowest level of ,electrical-current which can harm thehuman-body is normally-measured in ?
Microamps .
Kiloamps .
Amps.
Milliamps.

Research . has shown that a person is in , serious-danger of afatal-electric-shock at . or approximately 30 - Milliamps . :gettree:

 

[B16 Tom]

Just got home from my 2394 online exam. All the qusetions seem to be on Insuation resistance and RCDs.
Ie Why do we use RCD protection for additional protection? Is it for <50v touch voltage? Is it for Ma protection? etc etc.....
how would you test a 100Ma RCD a)0.5x and 1x b)0.5x 1x 5x etc etc..... Testing for 300ma rcd cant rememver anymore?? if i can will post here.

 

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Q). All electrical test probes and leads must complywith the standards set by the . ?
BS-EN-60898.
BS-7671:2011.
H&S Guidance note GS-38.
IET Regulations Part - 3 .

Q). For electrical test results to bevalid the test instruments used . ?
Mustbe new .
Mustbe of an approved type .
Must have a calibration certificate .
Musthave a digital readout .

Q). The test required by the IETRegulations to ascertain that the Circuit-protective-conductor is correctly connected is called . ?
Basicprotection .
Continuityof ring-final-circuit-conductors .
Continuityof protective-conductors . 612.2.1.
Earth-electrode-résistance.

Q) . The valueof a satisfactory-insulation-résistance-test on each final-circuit of a 230V installationmust be . ?
Less than 1Ω
Less than 0.5MΩ
Not less than 0.5MΩ
Not less than 1MΩ .. ( Table - 61 ) Up to and including 500V, ►►►► Minimum-insulation-résistance - 1.0MΩ . Circuit-nominal-voltage . ( V) -&-s . 100%

Q) . Instrument-calibration-certificate are usually valid for a period of . ?
3 months
12 months
3 years
18 months

Q) . What shouldbe given to the client when testingis completed . ? 632.1.
Original-test-documentation .
Copy of the drawings .
Technical advice on the use of equipment .
Designer’s- specifications .

Frequency of periodic-inspections , GN-3 . p.64 . table- 3.2. ( recommended-initial-frequenciesof inspection of electric-installations )
Q) . Aninstallation has been in use for , 10 years , Which test-procedures is most-appropriate. ?
Minor -works
Initial-verification
Periodic-inspection and testing .
Portable-appliance-testing .

Q) . What does not from part of test-documentation . ?
Electrical-installation-certificate ( EIC )
Schedule-test-results - (Generic )
Schedule of inspections - ( fornew-installation-work-only )
designer-specifications.

Q) What is not requirement during testing . ?
Costs are kept down .
No danger is caused to persons .
No danger is caused to livestock .
Avoiding damage to property .

Q) What is the displacement of the three-phases in , athree-phase-supply . ?
180 degrees
90 degrees
120 degrees - each with a Phase- displacement of 120° from each other . Electrical-degrees
45 degrees

 

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B16 - Tom . Off to work now . will domy best to get back to you somewhere alongthe line . Read some of the posts .


To provide additional-protection against , electric-shock , an RCD musthave a rated-tripping-current of no more than 30mA .

RCD - Earth-fault-conditions . 0.04s . Not -0.4s
Constantly monitors the electric-current through on or more-circuits,it is used to protect . ( residual - current ) dual - current . line/ Neutral

30mA . 30 /1000 = 0.03A

50% . of 30mA ,15mA . the RCD . should not trip .
500%.of 30mA, the RCD . should trip in under 40mS


Calculations for determining touch-voltage is( Ze ) the rated ( mA ) of an RCD . RCD - 100mA ?
TT - system . 200Ω , 200Ω x 100mA ÷ 1000 =20V

Touch-voltage .
50V / 0.03A = 1666.6666 . 1667Ω
50V / 0.1A = 500Ω


RCD- Testers .

GN-3.84
i).Should be capable of supplying full-range oftest-currents . 50% . 100% . 500%. - ½ . x1 . 5 x .
ii).-&-s . Test -current should be applied for . no-longer than . 2 seconds .RCD - Only
iii).Instrument to . BS-EN-61557-6 . willsatisfy the above .

Re-cap.GN-3. p.58
Operation of . residual-current-device . ( Big time -&-s )
411.4.5.
For each of the tests . readings should be taken on . both positive & negative . half-cycles and the. longer-operating-time-recorded.

 

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AdditionalProtection :

Is the , Presence of residual-current-device .

Theinspector should check that AdditionalProtection has been provided by a residual-current-device . RCD having the operating-characteristics .Section - 415 .

Regulation- 411.3.3.

Socket-outletswith a rated-current not exceeding 20A that are intended for , general-use byordinary-persons .
Mobile-equipment with a current-rating not exceeding 32A for use outdoors .

Insulation-Résistance between-Live-conductors & Earth .

Table- 61 . the Minimum-acceptable-value for a 400 / 230V installation , ( ≥ 1.0MΩ )

Regulations have to statedthe facts , Table - 61 . Up to & including 500V , ( ≥ 1.0MΩ )


How do you test a 100mA - RCD . ? . Megger- 1552. 3 x - setting , ½ . x1 . 5x , let narrowit down , ( 50% / 500% - is for Additional Protection - 30mA)

( ½ /50% ) 15 - half of 30mA . No-trip.
x5 - 500% . 30mA - 40mS . will -Trip

leavesus , x1 . 100% - BS-EN-61009-1 . 100mA - 100% , 300mS . Hint ! You do not test ( 5x times rating ) 100mA

Note : BS- only , 200mS
Note : BS-EN only , 300mS

P.295- Regulations have to statedthe facts , Table - 3A - time/current performance-criteria for RCDs , to BS-EN-61008-1 & BS-EN-61009-1
( Right if we screw it UP . 5x 100mA is 500mA , to much to inject into theinstallation ) this is what -&-s are looking for . Will you **** it Up . ! impairing-safety. You do not do this . :17:

Watch your Questions here , RCDs !! . ( G ) or ( S - type) delayed type

2 x , testing required of RCDs . 30mA , 50% & / 500% ( G ) General-purpose RCD .

BS-7671:2011: recognizes ( 2 xtypes ) of protective-devices for disconnection of the circuit is required in a , ( TT ) system under-fault-conditions .

An - RCD .
An Overcurrent-protective-device . Circuit-breaker.

415.2.The use of RCD , is not recognized as asole-means of protection and does not ,obviate the need to apply , one of the protective-measures Etc

Wherean RCD is used for , ( Earth ) fault-protection , Regulation - 411.5.3. requires the following condition to be fulfilled :
0.2s ) maximum-disconnection-time for a.c. final-circuits not exceeding 32A .

Under, ( Earth ) fault-conditions the RCD will take it out , 0.04s Lessthan , 0.2s . whilst the circuit-breakerthinks about it . the RCD has used its Presences .

By-calculations : Maximum-prospective-short-circuit-current , Line to Neutral , 230V / 0.05Ω = 4600A , 4.6kA ( PSCC )

An RCD : provides protection against , earth-faults occurring in equipment & reduces theeffect of Electric-shock . Etc


Must dash to work . 14:20 . in & out