***Cont../ Useful Information for Electricians & Apprentices***

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O.S.G.. The use of other methods’ of determining Maximum Demand is Not Precludedwhere Specified by the Installation Designer

FirstlyI make no Apologies for the Way am Writing on any Matters . it can be a first day Apprentice or some one Needing aJog of Memory .
Sowe are all in the Same Boat . “ To Learn “

For the Apprentices . The Day we stop learning is the Day we hang Upour Tool-Bag

CookerDesign Current Calculations

Thefirst thing you have to do is get Your Head around the Calculations !!

(From a Design point of View ) 2392-10

DomesticInstallation Oven(s) & Hob(s) are to be Calculated upon their MAXIMUM LOADING
Startwith a simple Calculation ( An Oven has a rating of 2kW ) 2000

(I = P/V ) Formula … I = 2000 ÷ 230V = 8.70A …. Weare Using the Unit Amps


2392-10/ Domestic Installation Oven(s)

Ovenhas 4 Rings ( 2 x 1kW ) & ( 2 x 1.5kW ) & Grill ( 2kW ) & Oven (3kW )

-Controlled via a CookerSwitch with a Socket outlet .

Asa Designer . we’ll have to Apply Diversity ??

Important )- Diversity allowance to be Applied to the FULL LOAD CURRENT for CookingAppliances .

TheO.S.G. is telling us . Purpose of the Final Circuit fed from theConductors )
O.S.G.Table 1B p/97 – column (3) Cooking Appliances → At the Top of the Page Note : Type ofPremises ( 2392-10 → Household Installations ) Domestic Installation(s)

DomesticInstallation(s) Only O.S.G. - 10A + 30% f.l – Full Load ) of connected Cooking Appliances in the Excess of 10A+ 5A if a socket-outlet is incorporated in the Control Unit . ( C.C.U. ) – 45A + 13A Socket Switched with Neon .

Fromyour point of View ( The First 10A ofthe rated current plus 30% of the reminder ( Plus) 5A if the Control Unit incorporates s Socket.

Calculations)- You bank “ Hold OFF“ the first 10 Amps of the Maximum Load Current )
The10A will be used at the End of the Calculations’

-So your Work out the Total Power Rating & then calculate the Full Load Current

Calculations)- Power = ( 2 x 1 ) + ( 2 x 1.5 ) + ( 2+ 3 ) = 10kW

I= 10000 ÷ 230V = 43.48A … round it up to the first four numbers43.47826087 ( 48 ) 43.48A

UsingDiversity allowance stated ↑↑ ( 43.48A sub 10A = 33.48A )

I= 33.48 x 30 ÷ 100 = 10.04A

Youradding the ( 5A ) for Socket outlet . I = 10A + 10.04 + 5A = 25.04A )- Asa Designer this is your Expected Current Demand .

Remember )- Supply Cables Rated to suit DesignCurrent ( Iz )

 

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□ Abstract/ Scope .

Laysdown requirements for the Verification . by inspection & testing . of thecompliance of the installation with the relevant requirements of other parts of EN-60364 .Criteria for testing are given & tests described . Thispart is concerned only with new installations : it is not concerned withinspection & testing of existing installations : However . the criteria for inspection & the tests described may beapplied . if thought appropriate . to existing installations .

Keywords - Building :Electrical installation : Verification : Initial verification .

Other standards to which reference is made in the Regulations . No 1

p/290- Superseded by – HD – 60364-6: 2007 . Initialverification


□ Reference
Low voltage electrical installations . Part 5-54 : Selection anderection of electrical equipment – Earthing arrangements . protectiveconductors & protective conductors

Abstract / Scope .
Addressesthe earthing arrangements . protective conductors & protective bondingconductors in order to satisfy the safety of the electrical installation . Hasthe status of a basic safety publication in accordance with IEC Guide 104 .

p/290- HD 60364-5-56 : 2007 - EarthingArrangements . No 1

Keywords – Building .Electrical installation . Earthing arrangement . Conductor; protection .


□ Reference – HD60364-1 : 2008 . p/290 .

Low-voltage electrical installations . Part 1 : Fundamentalprinciples . assessment of general characteristics . definitions .

Abstract / Scope .

Givesthe rules for the design . erection . and verification of electricalinstallations . The rules are intended to provide for the safety of persons .livestock and property against dangers and damage which may arise in thereasonable use of electrical installations and to provide for the properfunctioning of these installations . IEC-60364-1 . applies to the design . erection & verification of electrical installations suchas those of . a ) residential premises : b ) commercial premises : c ) publicpremises : d ) industrial premises : e ) agricultural & horticulturalpremises : f ) prefabricated buildings : g ) caravans . caravan sites &similar sites : h ) construction sites . exhibitions . fairs & otherinstallations for temporary purposes : i ) marinas : j ) external & similar installations : k ) medical locations : I ) mobile ortransportable units : m ) photovoltaicsystems : n ) low-voltage generatingsets : IEC- 60364-1 covers : a ) circuitsupplied at nominal voltages up to & including 1000V a.c. or 1500V dc : b )circuits . other than the internal wiring of apparatus . operating at voltagesexceeding 1000V & derived form aninstallation having a voltage not exceeding 1000V a.c. for Example . dischargelighting . electrostatic precipitators : c ) wiring systems & cables not specifically covered by the standardsfor appliances : d ) all consumerinstallations external to buildings : e ) fixed wiring for information &communication technology . signalling . control & alteration of theinstallation & also part of the existing installation affected by theextension or alteration .

 

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Adisadvantage of some RCBOs is that you cannot tell if they tripped by Overcurrent . or an EarthFault . This can make Fault finding harder .

RCDshave to be designed to interrupt fault currents. They will beat the Fuse / MCB in doingso . in the case of a fault current to Earth . RCD must trip within ( 0.04seconds ) - ( Unless time delayed type ) whereasFuse / MCBs is allowed ( 0.4 or 5 seconds ) dependingon circumstances . :banghead:

RCDscan also be switched OFF manually & can take the place of the IsolatorSwitch in the Consumer Unit . ( if theybreak Line & Neutral )

 

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2392-10: RCDs - Nuisance Tripping . One Cause . :13:

Oneof the common cause of RCD trips usuallyoccurs when the RCD is fitted for the ► First Time ◄ (- Theyshow up Neutral / Earth Faults NOT previously known to exit .
Currenttaken by the Load does NOT flow equally in the Neutral & Live conductorsthrough the RCD it will see this as (Residual Current & Trip )

Thisis NOT anuisance trip !!. The RCD is correctly stating there is a Problem. :banghead:

Basics.
i) residual - resi “ dual “ / Meaning . Two. L/N
ii)residual current “ Current “

 

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Basics.

ii)residual current “ Current “

AnRCD protects by constantly monitoring the Current flowing in the Line & Neutralconductors . Under normalcircumstances .

Current flowing in the two Wiresare ( Equal ) T&E :13:

UnderFault conditions ( Imbalance Occurs ) - Trip .

 

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Basics.

RCDshave another “ Important Advantage “ they reduce the risk of Fire bydetecting Leakageto Earth in Cables .
RCDswork on the principle “ What goes IN must come OUT .

Comparingthe “ CURRENT“ flow in both Line/ Supply . & Neutral / Return .

 

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RCD - protection . Therequirements of Regulation 314.1. Division of Installation . need to be taken into account . whendesigning & installing the circuitprotective arrangements . 314.1. States thatevery installation shall be divided into circuits as necessary to .

i) avoid danger & minimize inconvenience in the event of afault .
ii)
iii) take account of danger that may arise from the failure of a single circuit such as a lighting circuit .
iv) Reduce the possibility of unwanted tripping of RCDs due toexcessive protective conductor ( PE ) currents not due to a Fault .

( protective conductor currents ( PE ) produced by equipment innormal operation )

Meansa Single RCD cannot be Used to protect the whole installation . ( As in theevent of a fault . The Supply will be lost to all circuits ( Inconvenience / Danger )

 

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RCDs are NOT designed to break the HighShort Circuit Currents . Etc . Must beused with an Overcurrent Device / MCB

RCBO / will . Overload - Short circuit . p/34

 

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Whereprotection is provided by an RCD . The effective operation of each RCD . shall be verified by a Test simulating anAppropriate fault condition independentof any Test facility incorporated in the device .

30mA– 0.03A .
10mA– 0.01A .

2392-10 (- On.Site.Guide :- does “NOT “ express any preference between Ring FinalCircuit or Radial Circuit(s) . Both circuit(s) are available to Designers / Electricians

Radial& Ring Final Circuit(s) & NO preferenceis assigned to any Circuit(s) Designers / Electricians are free to choose any of the Three StandardsCircuit(s) A1 – A2 – A3 .
Regulation 314.3.
Thisallows the designer to develop final circuit(s) coving different ( Floor areas ) & using different ratingsof protective devices

Useful Junk . “ ConductorSize “

Theconductor size for a fused spur is determined from the total current demand served by that spur .Which is limited to a maximum of 13A .

 

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Justa Thought .

TheLoad current in both legs of the Ring Final Circuit is shared as Equally as Possible. :icon_bs:

2392-10(- if we look around the Kitchen . Everything is grouped aroundthe Sink . W/machine . T/dryer /D/Washer . Etc .

Ifthe Sink does NOT happen to be more or less in thecentre of the Ring Final Circuit . One leg will carry MOREcurrent than the OTHER . ???

 

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SELV.

A voltage NOT exceeding 50V a.c. or 120V d.c. between conductors at any point of a circuitwhich is separated from circuits with higher voltages & from earth byinsulation at least equivalent to that for ( Class II ) or which has equivalent protective means .

SELV. p/34
( separated extra-low voltage ) An extra-low voltage system which iselectrically separated from earth 7 from other systems in such a way that asingle fault cannot give rise to the risk of electric shock .

Final Circuit . p/28
A circuit connected directly to current-using equipment . or to asocket-outlets or other outlet points for the connection of such equipment .

Fixed Equipment . p/28
Equipment designed to be fastened to a support or otherwisesecured in a specific location .

SupplyPoint .
A pointat which electrical energy is delivered .

Origin of a Installation / Circuit .p/31 .
The position at which electrical energy is delivered to an electricalinstallation .

Stationary Equipment . p/35 . -&-s
Electrical equipment which is either fixed or which has a massexceeding ( 18kg ) & is not providedwith a carrying handle .

( This value of thisMASS is GREATER than 18kg . in standards relating to Household Appliances ) Domestic. CoP /2392-10

RadialFinal Circuit .
A finalcircuit that serves two or more points including socket-outlets .

Ring Final Circuit . p/34 .
A Final Circuit arranged in the form of a ring & connected toa single point of supply .

Spur . p/34
A branch from a ring or radial final circuit .

Portable Equipment . ( see Mobile Equipment ) p/32 .
“ Mobile Equipment “ Portable Equipment – deprecated )) p/31 .
Electrical equipment which is moved while in operation or whichcan easily be moved from one place to another while connected to the supply .

 

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UsefulJunk

Reason . BS-1363. p/278 BS-1363

1gang & 2 gang 13A . switched socket –outlet .
The switch avoidsUnnecessary Wear on the socket as it can beswitched OFF rather than Unplugged .

13ARectangular Pin Plug . 1362 : 1973 – ( 1992 ) p/278
Commonlyreferred to as . “ Flat / pin . Square / pin . Fused Plug . Commonly used sizes . 3A . 5A . 13A . CoP .

BS-1363. Fused connection unit with double pole switch & front flex outlet ‘
Reason . Used to supply permanentlyconnected appliances & also provides a meansof control . By removing the Fuse we have Isolation . Lock / OFF . M/K

FusedConnection Unit . Unswitched with Neon . should be used it is requiredthat the appliance should NOT be accidentally SwitchedOFF . Alarm/circuits & Freezers’ .

Socketoutlets provide an easy & convenient method by which portable appliancesmay be connected to the electrical supply . BS-1363

TheBritish . Ring Final Circuit system . & BS-1363 .

13Aplugs . socket-outlet(s) . connection unit(s) & adaptors plug &socket-outlet system were Introduced into the UK. In 1947 .

PDF] THE ORIGIN OFTHE BS 1363 PLUG AND SOCKET OUTLET ... Useful Junk . Good Reading.

 

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O.S.G. . Back of the Book .we have Electrical Symbols . to Use .

 

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2392-10 (- It is recommendedthat twin socket-outlet(s) be installed rather than single types as the initialcost is low in relation to having them replaced at a later date . .
2392-10 (- The following Guidelines as to recommended numberof Socket-Outlet(s) per location in a Typical Domestic Dwelling . O.S.G. P/178 . Table H7

 

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Note : Other methods are Not precluded .

2392-10(- Ring Final Circuit .

Thecable used must be capable of carrying (0.67 times ) the rated current of the protective Device . On the circuit .
Example. This is ( 2.5mm[SUP]2[/SUP]) Which has a current carrying capacityof ( 32A) When installed in Normal Domestic Installations.

Usingthe Factor of ( 0.67times ) we can calculate the maximumload on the circuit .

Calculation. Maximum Load on Cables .. 23 ÷ 0.67 = 34.33 Amps .

Alternatively.

Givena protective device current rating . find the minimum . Current Carrying Capacity of the cable required .

Calculation. Minimum . C.C.C. of Cable . 32 x 0.67= 21.44Amps

MCBwith a rating of ( 32A ) is fitted to a Ring Final Circuit(s) in DomesticInstallation(s) This provides protectionfor ( 2.5mm[SUP]2[/SUP] ) cables

Ring Final Circuit arrangements Regulation . 433.1.103 .
(iv) taking account of the totalfloor area being served . ( Historically . a limit of 100m[SUP]2[/SUP] has been adopted ) p/425 :13:

 

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Note : Other methods are Not precluded .

2392-10(- Ring Final Circuit .

Thecable used must be capable of carrying (0.67 times ) the rated current of the protective Device . On the circuit .
Example. This is ( 2.5mm[SUP]2[/SUP]) Which has a current carrying capacityof ( 23A) When installed in Normal Domestic Installations.

Mistakein calculations . ( 23A ) ◄◄

 

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Cooker Example .Calculation .

Note :Other methods are Not precluded . :banghead:

To ascertain the total loading of an electric cooker,the loading of the individual elements, motors, lights etc. must be added. Forexample, the total load of a typical electric cooker is comprised of thefollowing loads:

Boiling Ring RH Rear . 2000 W
Boiling Ring RH Front . 2000 W
Boiling Ring LH Rear . 2000 W
Boiling Ring LH Front . 2000 W
Grill Element . 1800W
Oven Element LH . 1200 W
Oven Element RH . 1200 W
Hot Cupboard Element . 500 W
Oven Lamp . 40 W

Total Load 12,740 W

The full-load current of this cooker may now becalculated:

FullLoad Current = Load in Watts
…………………………Full Load Current

I = 12740
…. 230

I = 55Amps approximately

However,diversity is allowed and should be assessed as follows:

The first 10 Amps of thetotal rated current of the cooker, plus 30% of the remainder of the total ratedcurrent.

First 10A = 10 A

30% 0f Remainder = (55 – 10 ) x 30% = 13.5 A

Total = 10 +13.5 = 23.5 A

 

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Instantaneous ElectricShower(s) . O.S.G.- Table– A2 .

AnElectric Shower heats only the required amountof water ( Instantaneously) Wording .

 

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Wiring Regulation Restrictions.

Domestic Installation(s) . The total ( REN ) –Ring equivalent number . value of all Telephone equipment connected on a Line must NotExceed ( 4 )

 

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2392-10: MK . Switch Disconnectors 100A . BS-EN 60947-3.

17[SUP]th[/SUP] Edition 2011 . Regulations . 537.2.2.1. & 537.2.2.2. p/151.

Devices for Isolation . 537.2.2.1.
A device for ( Isolation ) shall ( Isolate ) all live supply conductor(s) from the circuit concerned .subject to the provisions of Regulation 537.1.2.

A device suitable for isolation shall be selected according to the requirements which are basedon the overvoltage category applicable at the point of Installation . Etc .

Equipment used for ( Isolation ) shall comply with Regulation(s) 537.2.2.1. & 537.2.2.2. to ( 6 ) ◄◄ :13:

537.2.2.2. The position ofthe contacts or other means of ( Isolation ) shall be either externally visible or clearly& reliably indicated . An indication of the isolated position shall occuronly when the specified ( Isolation ) has been obtained ( in EACH POLE )

 

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2392-10: MK . Miniature Circuit Breaker(s) MCBs . BS-EN 60898 : 2003 .

17[SUP]th[/SUP] Edition 2011 . Regulations . 537.2.2.1. & 537.2.2.2. p/151.

When the Green Indicator is Visible . ( Then a contact gap of 4mm has been ACHIEVED ) “ Supply is Cut-OFF “

BS-EN 60898 : requires the tripping to occur within ( 100milliseconds ) Fault Current of up to6000A .

 

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2392-10 : Learning Curve .

MK. Residual Current Devices ( RCDs ) D/P

BS-EN 61008: 1995 .

17[SUP]th[/SUP] Edition 2011 . Regulations . 537.2.2.2. & 537.3.2.2.

537.3.2.2. A device for switching OFF for mechanical Maintenance or acontrol switch for such a device shall require ( Manual Operation )

The ( Open Position ) ofthe contacts of the ( Device ) shall be ( Visible ) or be ( Clearly ) & ( Reliably Indicated )

Note : Theindication required by this regulation may be ( Achieved ) by the use of the (Symbols . “ O “ & “ I “ ) to indicate the ( Open ) & (Closed position respectively )

 

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2392-10: Let’s notforget . Fan Isolator can be Usedas a Double pole or T riplepole Isolator .

 

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ElectricalTesting .

TheElectrical Contractor is charged with the responsibility to carry out anumber of tests on an electricalinstallation .

Thereasons for testing the installation .

• To ensure that theinstallation compiles with the IET Regulations . 2011
• To ensure that theinstallation meets the specification .
• To ensure that theinstallation is safe to use .

 

[spaldingsparks]

Re: ***Cont../ Useful Information for Electricians’ & Apprentices***

Hi Amberleaf
Like the posts
I would also like to mention the wiring up of 3kw Immersion heaters, I have come accross a few over the years (old me) and if a standard 13A fused spur has been used they can suffer from the constant load (Heat Damage) as the circuit should be on its own, a 16amp MCB feeding a 20 amp double Pole switch works far better and then as seems to be common now days the addition of shower pumps ETC by the dreaded plumbers can still be run on a fused spur from the primary side of the DP Switch.
I hope this extra info helps all

 

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Functional Earthing . ( FE )

Q/ . if an RCD / RCBO is provided with a( functional earthing ) conductor . – for -&-s Q/As . Coloured White.
Q/ . May this conductor be connected toan Earthing Terminal ?

A/ . Yes .
Thepurpose of this conductor is to allow a (Return Path ) for the Electronic Circuit . if the Neutral is disconnected . ( To ensure the RCD still operatescorrectly )

Theconductor does NOT perform a Protective Earth Function .

RCBO. Will normally have two circuit(s) for detecting an ( Imbalance& Overload ) Same interrupt method ( Imbalance/ Trip RCD / RCBO . Overload/ MCB .

Testing / Verification .

Impedance – ( EarthFault Loop Impedance )

Q/ . When existing circuit(s) are extended or new circuit(s) installed . What limiting factors affect the ( Length of the Circuit )
A/ . Limiting factors - Voltage drop & Earth Fault Loop Impedance.

CircuitRoute – Length based on Loop Impedance . VoltageDrop . ( Vd ) Single-phase. Line & Neutral - Max 5% of 230V . Power

 

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Q / State the three generalrequirements to which the installed equipment must conform when carrying out anInitial Inspection .

i) The equipment is incompliance with standards . To the correct BS - or BS-EN .
ii) Correctly selected& erected in accordance with BS- 7671:2008: No 1: 2011
iii) It is not visiblydamaged .

State :-

Q / . i) When an InitialInspection & Testing should becarried out . 610.1. p/189
ii) The precautions to betaken during an Inspection & Testing

A / . i) During and on completion . before being put into service.
A / . ii) Avoid danger topersons . livestock and damage to property . 610.1. p/189

Justa reminder . 2392-10 . -&-s . 2012. The Q/As . are in the Regulations& GN-3.

632 – Initial Verification . p/196
632.1– 632.2. 632.3. 632.4. ◄ Important in -&-s Q/As . 2392-10 . No 1 2011

 

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Reporting. 2011

Electrical Installation Condition Report . 2392-10 : -&-s Q/As - 2012

The ElectricalInstallation Condition Report . ( EICR ) is intended to beissued when a ( Periodic Inspection ) of an electrical installation has been carried out .

The ( EICR) does NOT certify ANYTHING& . HENCE . must NOT be ISSUED tocertify NEW electrical installation work . ◄◄ 2392-10 : -&-s - 2012

Thepurpose of the ( EICR ) is to REPORT on the condition of an EXISTING electricalinstallation ◄◄

Ultimately. present one of two OUTCOMES .

□ Satisfactory. The installation is deemed safe for continued USE .
□ Unsatisfactory . Oneor more issues of safety have been IDENTIFIED .

 

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UsefulJunk . p/178

No Lampholder may be used on circuit(s) exceeding 250V – IET Regulation 559.6.1.2.

&all Metal Lamp holders must have anEarth Terminal .

Flexible Cords . Deleted byBS-7671:2008 . No 1 . P/28
Flexible Cable . A cable whose structure & materials make itsuitable to be flexed while in service .

 

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□ Intermediate Switching .

The action of the Intermediateswitch is to cross-connect the “strapping wires “
This gives us the ability toroute a supply to any terminal depending upon the switch contact position’s .

Intermediate Switching has two position’s.

□ Copper has better conductivity for a givencross-sectional area .

□ Ambient Temperature .
Current-carryingcables produce heat . & the rate at whichthe heat can be dissipated depends upon the temperature surrounding the Cable.

□ Direct Sunlight .
Cables sheathedin ( PVC ) should NOT be installed in positions where they are exposed todirect sunlight because this causes them to harden & crack . Ultravioletrays leach out the ( Plasticiser in the PVC ) making it hard & brittle .

Earthing:- p/27

BS-7671 defines “ Earthing “ as a connection of any exposed conductiveparts of an Installation to its Main Earthing Terminal .
This is done toensure that all the “ Metalwork “ associated with the Installation(s) is effectively connected to the General Mass of the Earth .

This means that. in the event of an Earth Fault . the voltage developed to Earth is restrictedto ( 230V ) this is the case even on a (400V ) three-phase supply . where automatic disconnection of the supply can beachieved .

Bonding:- p/23 .

BS-7671:2011. fails to define Bonding – but does define a ( Bonding Conductor )
Thisis a ( Protective Conductor proving Equipotentinal Bonding ) this in turn is defined as an ( ElectricalConnection maintaining various Exposed Conductive Parts & Extraneous Conductiveparts ) - Substantiallythe same Potential .

In Order forCurrent to flow . TWO conditions have to be MET :-

i) There has to be a circuit for current to passalong .
ii) There has to be a ( Potential Difference – Voltage )

 

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Useful Junk .

230V a.c. RCBOs. Commercial / Industrial - Flying neutral lead . 700mm ( equivalentto 27.6 inches )
230V a.c. RCBOs. Domestic – Single pole . - Flying neutral lead . 200mm ( equivalentto 7.87 inches )

 

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2392-10 . No - 2011

The test procedures must be followed carefully & inthe ( Correct Sequence ) As indicated by IET Regulation(s) - 612.1. p/190 .

This ensuresthat the ( ProtectiveConductors ) are correctlyconnected & secure before the ( Circuit is Energized )
The test(s) ofRegulation – 612.2. - to 612.13.

Wording . Visual Inspection. The IETRegulation 612.3. gives a Checklist forthe Initial Visual Inspection – of the Installation

□ Connection of conductors .
□ Identification of conductors
□ Presence of fire barriers . ETC . This can only be done by . Visual Inspection .

 

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2392-10 . No - 2011

Justa Reminder . as an Inspector .

If any ( Tests ) fails to comply with the IET Regulation(s) .
Then all thepreceding Tests must be repeated after the ( Fault ) hasbeen rectified .
This is becausethe earlier Test results may have been (Influenced by the Fault ) - Regulation. 612.1.

 

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Just a Reminder. 2392-10

Earth Fault Loop Impedance . 612.9.

During the Test. The instrument does an . Ohms law calculation& displays the test results as a ( Résistance Reading )

 

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Just a Reminder. 2392-10

Testing forContinuity of Protective Conductors . & Main & Supplementary Equipotential Bonding.
-&-s .point of View . The object of the Testis to ensure that the circuit protective conductor– CPC. ( iscorrectly connected ) -&-s

Total Résistancewhich is ( Low Enough to permit the Overcurrent Protective Device ) 2391-10 / 2392-10 . operate within the disconnection timerequirements . IET Regulation – 411.4.6. “ Motor “ gM . “ Generalpurpose “ gG

a) “ General purpose “ ( gG ) &motor circuit application ( gM ) fuses to BS-88-2 fuse systems ( E ) bolted & (G ) clip in.

As an Inspector/ should anEarth Fault Occur .

 

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DomesticInstallation(s) -&-s 2011

Just a Reminder . – 2392-10

Testing should be carriedout from the day the Installation commences – Regulation . 610.1 :rant:

Regulation . 610.1

Every installationshall . during erection & on completion before being put into service . be ( Inspected & Tested ) to verify . so far as is reasonablypracticable . that the requirements of the regulations have been met .

 

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Flexiblecord on which the lampholder is suspended performs two - functions ‘ it carries the electric currentto the lamp . & supports the weight of the holders . lamp & shade . “ its physical strength “ Theconnection is made by means of a ceiling rose .

Thevast majority of light fittings are installed above head height . so clearly itis important that the fittings are secure . BS-7671-2011 . requires that thefixing for light as a pendant set has to be capable of supporting a Mass of ( 5kg )

559.6.1.5. – p/178
Fixingof Luminaries .

Luminaries. must be fixed securely . & the means of fixing must be able to supportthe weight of the Luminaries . this fixing must be able to carry a mass of notless than ( 5kg )

16[SUP]th[/SUP] Edition . ◄► p/96. blast form the past . ◄ :icon_bs:

522-08-06 .
A flexible wiring system shall be installed so that excessivetensile & torsional stresses to the conductors & connections areavoided .

Flex & Cables . ( pendentLight Fittings )

Theweight of the light fitting may affectyour choice of flex size .
Current – rating . 0.5mm[SUP]2[/SUP] flex takesfittings . up to ( 2kg ) 16[SUP]th[/SUP] Edition . ◄ …….. (1) 100W - ( 3 ) ► x 230 = 690W = ( 2kg ) Load Limit . ( Just a Point)
0.75mm[SUP]2[/SUP] flex takes up to ( 3kg ) inweight . 16[SUP]th[/SUP]Edition . ◄
1.0mm[SUP]2[/SUP] flex will support fittings up to( 5kg ) 16[SUP]th[/SUP]Edition . ◄

StandardCeiling Rose should not be used for light fittings weighing more than ( 2.5kg )for very heavy fittings ( more than 5kg ) a supporting chain is necessary .

559.6.1.3. – p/178
CeilingRoses should only be used for ONE outgoingflexible cord “ Unless “ they aredesigned for multiple pendent’s .

UsefulJunk – 2392-10 . Example .

Lewden Plug in Ceiling Rose.
Thesafe & easy way to remove a light fitting from a Wall or Ceiling .Detachable Ceiling Rose enables . removal of light fittings without disturbing the fixedwiring 6A rated . Maximum Working Load for Hook ( 5kg )

Enclosures .

Theenclosure of any equipment “ Serves “ to keep out dirt . dust . moisture & Prying Fingers.

 

[galinkahaha]

real thanks for putting all the information it helped me with my ongoing course

 

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2392-10 . Fundament requirements for selecting allEquipment .

BS-7671:2011 .addresses equipment so far as ( Selection & Equipment ) within the Installation is concerned –Regulation . 113.1. p/15

 

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2392-10 .Just a Reminder.

Compliance withStandards . 511.1. p/113

□ Every item of equipmentshall comply with :-
i) Currenteditions or agreed amendment dates of its :
ii) Britishstandard .
iii)Harmonized standard .

Or

Compliance with aforeign standard based on IEC standard as long as the degree of safety isequivalent to ( BS- )

□ NOT covered by a BS- EN- orHD- then the designer or person responsiblefor ( Specification ) must establish that the same degree of safety as affordedby the regulations . 511.2.

 

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State )- thedifference between . & the requirements for ( Isolation )

□ Switching offor ( Mechanical Maintenance )
□ Emergencyswitching / Functional switching .

2392-10 .

Testing . One off the most Important things -&-s are looking for is )- Example .

State )- theuses of Monitoring .
□ Insulation .
□ ResidualCurrent .