***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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Thedifference between the First Amendment & 17[SUP]th[/SUP]Edition

Section 706 : 706.1. p/188 .

Theonly wording that is changed . added on .

This section does not apply to electrical systems as defined inBS-7909 used in structures . sets . mobileunits etc as used for public or private events , touring shows . theatrical .radio . TV or film productions & similar activities of the entertainmentindustry . :19:

 

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Thedifference between the First Amendment & 17[SUP]th[/SUP]Edition

Theonly wording that is changed .

Section 708 : 708.411.4.. p/223 . TN system ◄ . :19:
The Electricity Safety . Quality & Continuity Regulations 2002 ( ESQCR ) prohibit the connection of aPME earthing facility to any metalwork in a leisure accommodation vehicle (including a caravan )

This does not preclude the use of a PME earthing facility as themeans of earthing for other purposes . such as to the installations ofpermanent buildings .

Note : The requirements of other section of Part 7 . may alsoapply .

 

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Thedifference between the First Amendment & 17[SUP]th[/SUP]Edition

Theonly wording that is changed .

708.553.1. Plugs & Sockets-outlets . :19:
708.53.1.8. N/C .
708.53.1.9. N/C .
708.53.1.10. N/C .
708.53.1.11. N/C .

708.53.1.12. Each socket-outlet shall be protected by anindividual overcurrent protective device . in accordance with the requirementsof Chapter 43 .

A fixed connection for the supply to each leisure accommodationvehicle ( including caravans ) or tentshall be protected individually by an overcurrent protective device . inaccordance with the requirements of Chapter 43 .

708.53.1.13. N/C .
708.53.1.14. Socket-outletprotective conductors shall not be connected to a PME earthing facility .

The protective conductor of each socket-outlet shall be connectedto an Earth Electrode & therequirements of Regulation 411.5. for aTT system shall be complied with

 

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Thedifference between the First Amendment & 17[SUP]th[/SUP]Edition

Theonly wording that is changed . Section 709 .

709.1. N/C
709.3. N/C
709.313. N/C
709.41. N/C
709.41.3.5. N/C
709.41.3.6. N/C
709.411.4. TN-system . The Electricity safety . Quality & ContinuityRegulations 2002 ( ESQCR ) prohibit theconnection of a PME earthing facility to any metalwork in a boat .

This does not preclude the use of a PME earthing facility as themeans of earthing for other purposes . such as to the installations of permanentbuildings .

Note : The requirements ofother sections of Part 7 may also apply .

 

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709.5. N/C
709.512.2. N/C
709.512.2.1. N/C
709.512.2.1.2. N/C
709.512.2.1.2.3. N/C
709.512.2.1.2.4. N/C
709.521. N/C
709.521.1. N/C
709.521.1.4. . N/C
709.521.1.5. The following wiring systems . etc . ii) Non-sheathed cables in cable management systems . rest are the same .
709.521.1.6. . N/C
709.521.1.7. . N/C
709.521.1.8. . N/C
709.531. . N/C
709.531.2. .
709.533. . N/C
709.537.
709.537.2. N/C
709.537.2.1. N/C
709.537.2.1.1. N/C
709.553. N/C
709.553.1. N/C
709.553.1.8. N/C
709.553.1.9. N/C
709.553.1.10.. N/C
709.553.1.11.. N/C
709.553.1.12.. N/C
709.553.1.13. N/C

709.553.1.14. Socket-outletprotective conductors shall not be connected to a PME earthng facility .

Fig – 709.1. p/228 .

Main Switch . L1 / N / PE .
Main Switch . L / N / PE . – drawing the same .

Fig – 709.2. p/229 . – drawing the same .

The rest all the same . / The rest all the same . Instructions for Electricity Supply .

 

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Section710 : MedicalLocations .

710.411.3.3. Additional Protection .
Wherea medical ( IT ) system is used . additional protection bymeans of an RCD shall NOT be USED.

 

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Section740 :

740.1. N/C
740.1.1. N/C . Scope :- Note / Note . The permanent electrical installation is excludedfrom the scope .
740.3. N/C .
740.31. N/C .
740.313. N/C .
740.313.1.1. N/C .
740.313.3. ( Phase to Line ) N/C .
740.4. N/C .
740.4.1. N/C .
740.410.3. N/C .

( NEW ) 740.410.3.5. - The protective measures of obstacles ( Regulation 417.2 ) is not permitted .
Placingout of arms reach is acceptable for electric dodgems ( Regulation 740.55.9. )

740.410.3.6. N/C .

( The Electricity at Work Regulation “ 1989 “ ) Design . Erection – Verification ElectricalInstallation in Fairgrounds . ( YES )

740.411. N/C .
740.411.4. TN-
( NEW ) 740.411.4.1. A PME earthing facility shall not be used asthe means of earthing for an installation falling within the scope of thissection .
Note : The ESQCR . prohibitthe use of a PME earthing facility asthe means of earthing for the installation of a caravan or similar construction.
( NEW ) 740.411.4.3. Where the type of system earthing is . TN- . a PEN conductor shall not be used downstream ofthe similar construction .
740.411.6. N/C .
740.415. N/C .
740.415.1. N/C .
740.415.2. N/C .
740.415.2.1. N/C .
740.415.2. N/C .
740.415.2.1. N/C .
740.42. N/C .
740.422.3. N/C .
740.422.3.7. N/C . -

 

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740.5. N/C .
740.51. N/C .
740.512. N/C
740.512.2. N/C
740.52. N/C
740.521. N/C
740.521.1. – Conduit systemsshall comply with the relevant part of the BS-EN . That’s . it Wording . Rest ok .

NOTE . 2 ) Where mechanical protection of cables is provided . p/221
The following methods are considered to meet the aboverequirements . p/270

(i) ◄ Conduit systems shall . etc .
(ii) ◄ Cable trunking systems & cable . etc .

NOTE . 3 ) Cable of type H07RNF . Changed to NOTE 2 . Restok .

740.526. N/C
740.53. N/C
740.537.1. N/C
740.537.2.1.1. N/C
740.537.2.2. N/C
740.55. N/C
740.55.1. N/C
740.55.1.1. N/C
740.55.1.2. N/C
740.55.1.3. N/C
740.55.1.4. N/C
740.55.1.5. N/C
740.55.3. N/C
740.55.3.1. N/C
740.55.3.2. N/C
740.55.5. N/C
740.55.7. N/C
740.55.8. N/C
740.55.9. N/C
740.551. N/C
740.551.8. N/C
740.6. N/C

 

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Appendix2 ( Informative ) p/240

StatutoryRegulations & Associated Memoranda .

( vi ) Theatres & otherplaces licensed for public ETC.
conditions of licence under : (a) in England& Wales. The local Government ( Miscellaneous provisions ) Act 1982.
(a) The Secretary of state for the Home Department .

Statutory Regulations & Associated Memoranda . p/292

( vi ) Theatres & otherplaces licensed for public ETC.
conditions of licence under : (a) in England& Wales. The local Government licensingAct 2003.
(a) Department for Culture . Media & Sport .

 

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UsefulJunk : ( ESQC ) Whereto find it .

17[SUP]th[/SUP] Edition p/241 & FirstAmendment . p293

UnderRegulation 28 . of the Electricity Safety . Quality & Continuity Regulation 2002 . requires distributors to provide the following information to relevantpersons free of charge .

- The maximum prospective short-circuit currentat the supply terminals .
- The maximum earth loop impedance of the earthfault path outside the installation ( Ze )
- The type & rating of the distributorsprotective device or devices nearest to the supply terminals
- The type of earthing system applicable to theconnection .
- The number of phases of the supply
- The frequency of the supply & the extentof the permitted variations .
- The voltage of the supply & the extent ofthe permitted variations .

 

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First Amendment . p/4

Introduction to BS-7671:2008 .

Note 2 )- Particular attention is drawn to Section 701 . This section now allows socket-outlets (Other than SELV & shaver supply units to BS-EN 61558-2-5 ) to be installedin locations containing a bath or shower ( 3m ) horizontally beyond theboundary of zone 1 .

 

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SWA. ?? Example . :hurray:

□ The Wire Armouring is ( Steel ) & therefore is ( Conductive ) The steel is covered by an Exposed Oversheathof Insulation . So not Exposed .
□ The cable is Terminated on mostinstallation(s) with ( Brass-glands ) which are ( Conductive ) These parts aretherefore ( Exposed conductive parts ) these may also be covered with ( PVC. Shrouds )

“ Function(s) “

TheArmouring is to protect the Cable against ( Mechanical damage ) & to allow the cableto be run out of safe Zone .
TheArmouring is connected to Earth to enable the supply to be ( Automatically disconnected) by the ( Circuit Protective Device ) Underthis Fault Condition(s)

Types of ProtectiveConductor . 543.2. :svengo:

543.2.1. A protectiveconductor may consist of ( One ) or ( More ) of the following .

i) A single-core cable .
ii) A conductor in a cable.
iii) A An insulated or bare conductor in a common enclose withinsulated live conductor(s) .
iv) A fixed bare orinsulated conductor .
v) A metal covering . for example . ( THE sheath . screen orarmouring of a cable )
vi) A metal conduit . metallic cable management system or otherenclosure or electrically continuous support system for conductors .
vii) An (Extraneous-conductive-part ) complying with Regulation 543.2.6.

 

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Defining Protective Conductor . p/32

Protective Conductor isdefined in ( PE ) (BS-7671:2008 ) First Amendment . underPart 2 Definitions as .

A conductor used for some measures of protection against electricshock & intended for connecting together any of the following parts .

- Exposed conductive parts.
- Extraneous conductiveparts .
- The main earthing terminal .
- Earth electrode(s) .
- The earthed point of the source . or an artificial neutral .

 

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Earthing Arrangements for Protective Purposes . 543.6. :svengo:

543.6.1. – Where overcurrent protective devices areused for fault protection . the protective conductor shall be incorporated inthe same wiring system as the live conductors or in their immediate proximity .

 

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134.1.4.p/19 – p/21.
Erection )- Terminating the Cable Ends of S.W.A. cables . :20:

BS-7671:2008. Fundamental requirements set out in Regulation . FirstAmendment / 17[SUP]th[/SUP] Edition

Everyelectrical joint & connection shall be of proper construction as regards Conductance . Insulation. Mechanical strength & Protection .