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30154063 pdf BRITISH STANDARD BS EN 50464 1 2007 Three phase oil immersed distribution transformers 50 Hz, from 50 kVA to 2 500 kVA with highest voltage for equipment not exceeding 36 kV — Part 1 Gene[.]

BRITISH STANDARD Three-phase oil-immersed distribution transformers 50 Hz, from 50 kVA to 500 kVA with highest voltage for equipment not exceeding 36 kV — Part 1: General requirements ICS 29.180 BS EN 50464-1:2007 +A1:2012 BS EN 50464-1:2007+A1:2012 This British Standard is the UK implementation of EN 50464-1:2007+A1:2012 It supersedes BS EN 50464-1:2007, which will be withdrawn on 31 October 2014 The start and finish of text introduced or altered by amendment is indicated in the text by tags Tags indicating changes to CENELEC text carry the number of the CENELEC amendment For example, text altered by CENELEC amendment A1 is indicated by !" The UK participation in its preparation was entrusted to Technical Committee PEL/14, Power transformers A list of organizations represented on this committee can be obtained on request to its secretary This publication does not purport to include all the necessary provisions of a contract Users are responsible for its correct application Compliance with a British Standard cannot confer immunity from legal obligations This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 July 2007 © The British Standards Institution 2012 Published by BSI Standards Limited 2012 ISBN 978 580 75415 Amendments/corrigenda issued since publication Date Comments 29 February 2012 Implementation of CENELEC amendment A1:2012 EUROPEAN STANDARD EN 50464-1:2007+A1 NORME EUROPÉENNE EUROPÄISCHE NORM January 2012 ICS 29.180 Supersedes EN 50464-1:2007 English version Three-phase oil-immersed distribution transformers 50 Hz, from 50 kVA to 500 kVA with highest voltage for equipment not exceeding 36 kV Part 1: General requirements Transformateurs triphasés de distribution immergés dans l'huile, 50 Hz, de 50 kVA 500 kVA, de tension la plus élevée pour le matériel ne dépassant pas 36 kV Partie 1: Prescriptions générales Ölgefüllte Drehstrom-Verteilungstransformatoren 50 Hz, 50 kVA bis 500 kVA, mit einer höchsten Spannung für Betriebsmittel bis 36 kV Teil 1: Allgemeine Anforderungen This European Standard was approved by CENELEC on 2006-12-01 CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member This European Standard exists in three official versions (English, French, German) A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels © 2007 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members Ref No EN 50464-1:2007 E BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) -2- Foreword This European Standard, prepared by the Technical Committee CENELEC TC 14, Power transformers was submitted to the formal vote and was approved by CENELEC as EN 50464-1 on 2006-12-01 This European Standard supersedes HD 428.1 S1:1992 + A1:1995 and HD 428.3 S1:1994 The following dates were fixed: – – latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2007-12-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2011-12-01 The EN 50464 series consists of the following parts, under the general title “Three-phase oil-immersed distribution transformers 50 Hz, from 50 kVA to 500 kVA with highest voltage for equipment not exceeding 36 kV”: Part General requirements Part 2-1 Distribution transformers with cable boxes on the high-voltage and/or low-voltage side – General requirements Part 2-2 Distribution transformers with cable boxes on the high-voltage and/or low-voltage side – Cable boxes type for use on distribution transformers meeting the requirements of EN 50464-2-1 Part 2-3 Distribution transformers with cable boxes on the high-voltage and/or low-voltage side – Cable boxes type for use on distribution transformers meeting the requirements of EN 50464-2-1 Part Determination of the power rating of a transformer loaded with non-sinusoidal currents Part Requirements and tests concerning pressurised corrugated tanks Foreword to amendment A1 This document (EN 50464-1:2007/A1:2012) has been prepared by CLC/TC 14, "Power transformers" The following dates are fixed: • • latest date by which the document has to be implemented at national level by publication of an identical national standard or by endorsement latest date by which the national standards conflicting with the document have to be withdrawn (dop) 2012-10-31 (dow) 2014-10-31 Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent rights -3- BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) Contents Scope Normative references Electrical characteristics 4 3.1 Rated power 3.2 Highest voltages for equipment for windings 3.3 Rated voltages of windings 3.4 Tapping 3.5 Connections 3.6 Dimensioning of neutral connection of the low-voltage winding 3.7 Short-circuit impedance 3.8 Losses and sound power level 3.9 Tolerances and penalties 10 3.10 Tests 10 3.11 Insulation levels and dielectric tests 10 Design requirements 10 4.1 Type of oil preservation system and degree of sealing 4.2 Terminal markings 4.3 Terminations 4.4 Distance between bushings 4.5 Rollers Accessories Efficiency and voltage drop (at reference temperature) 12 10 10 10 11 11 11 6.1 Efficiency 12 6.2 Voltage drop ( u%) 13 Annex A (informative) Capitalisation evaluation 14 Bibliography 15 Tables Table – Connections for distribution transformers Table – Load losses P k (W) at 75 °C for U m 24 kV Table – No load losses P (W) and sound power level (Lw (A) ) for U m 24 kV Table – Load losses P k36 (W) at 75 °C for U m = 36 kV Table – No load losses P 036 (W) and sound power level (Lw (A) ) for U m = 36 kV Table – Accessories 12 BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) -4- Scope This document covers transformers from 50 kVA to 500 kVA intended for operation in three-phase distribution networks, for indoor or outdoor continuous service, 50 Hz, immersed in mineral oil, natural cooling, with two windings: − a primary (high-voltage) winding with a highest voltage for equipment from 3,6 kV to 36 kV; − a secondary (low-voltage) winding with a highest voltage for equipment not exceeding 1,1 kV NOTE This document may be applied, either as a whole or in part, to transformers immersed in a synthetic insulating liquid NOTE This document may be applied, either as whole or in part, to transformers having windings with more than one rated voltage In this case the rated power for each rated voltage shall be specified by the purchaser The object of this document is to lay down requirements related to electrical characteristics and design of three phases distribution transformers immersed in mineral oil Normative references The following referenced documents are indispensable for the application of this document For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies EN 50216 series Power transformer and reactor fittings EN 50464-2 series Three-phase oil-immersed distribution transformers 50 Hz, from 50 kVA to 2500 kVA with highest voltage for equipment not exceeding 36 kV EN 60076 series Power transformers (IEC 60076 series) IEC/TR 60616 3.1 Terminal and tapping markings for power transformers Electrical characteristics Rated power The values of the rated power are 50 kVA – 100 kVA – 160 kVA – 250 kVA – 315 kVA – 400 kVA – 500 kVA – 630 kVA – 800 kVA – 000 kVA – 250 kVA – 600 kVA – 000 kVA – 500 kVA The underlined values are preferred BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) -5- 3.2 Highest voltages for equipment for windings Insulation levels and dielectric tests shall be in accordance with the requirements of EN 60076-3 The values of the highest voltage for equipment are − for the high-voltage winding: 3,6 kV– 7,2 kV – 12 kV – 17,5 kV – 24 kV – 36 kV, − for the low-voltage winding: 1,1 kV 3.3 3.3.1 Rated voltages of windings For the high-voltage winding The rated value of the high voltage winding is above 1,1 kV, up to and including 36 kV 3.3.2 For the low-voltage winding The rated voltage shall be chosen among the following preferred values: 400 V – 410 V – 415 V – 420 V – 433 V NOTE This document may be applied, either as a whole or in part, to transformers with rated low voltages below 400 V and above 433 V 3.4 Tapping The HV winding can be provided with tapping The preferred tapping ranges are ± 2,5 % or ± x 2,5 % unless otherwise specified ,but in any case maximum taps shall not exceed positions and the total maximum range shall not exceed 15 % The tapping range has to be specified by the purchaser or by agreement between manufacturer and purchaser These taps shall be connected to an off-circuit tapping switch 3.5 Connections Connections shall be made in accordance with the provisions of Table Table – Connections for distribution transformers Rated power kVA 50 and 100 ≥ 160 U m ≤ 24 kV Y zn or D yn D yn U m = 36 kV Y zn or D yn D yn The clock hour figure shall be or 11 Connection symbol Y zn ; Y zn 11 ; D yn ; D yn 11 BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) -6- Connections and clock figure shall be specified by the purchaser NOTE This document may be applied, either as a whole or in part, to transformers having connections other than those mentioned above 3.6 Dimensioning of neutral connection of the low-voltage winding The neutral conductor and terminal of the low-voltage winding shall be dimensioned for rated current and earth fault current, unless otherwise specified 3.7 Short-circuit impedance The preferred values of the short-circuit impedance at a reference temperature of 75 °C are − for rated voltage ≤ 24 kV (refer to Table 2), − for rated voltage = 36 kV (refer to Table 4) NOTE Other values of short-circuit impedance may be specified by the purchaser for particular system service conditions, e.g in the case of parallel options 3.8 Losses and sound power level For transformers having listed values of rated power and preferred value of short-circuit impedance in accordance with 3.1 and 3.7, the values of losses and sound power levels are stated, for Um ≤ 24 kV, in Table (load losses) and Table (no load losses and sound power levels), for Um = 36 kV in Table (load losses) and Table (no load losses and sound power levels) The sound power levels given in Table for Um ≤ 24 kV and in Table for Um = 36 kV are the maximum admitted (no tolerance) Lower sound power levels can be specified by the purchaser To choose the correct load losses (Table or Table 4) and no load losses (Table or Table 5) or when the loss values stated in the tables not correspond to the actual evaluation of the energy cost, the transformers can be requested and offered with losses differing from the tabled losses; the capitalisation formula given in annex is applicable 3.8.1 Load losses, no load losses and sound power level for Um 24 kV !In the following tables, column A values correspond to the lowest losses as commonly used in EU for electrical devices Transformers can be requested and offered with LwA lower than the tabled values A “low noise” series with no load losses Do, Co or Bo can be proposed with the LwA from the tabled values of Do, Co, Bo or Ao respectively." BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) -7- Table – Load losses Pk (W) at 75 °C for Um ≤ 24 kV ! Rated power Ck Bk Ak Short circuit impedance kVA W W W % 50 100 875 750 100 750 475 250 160 350 000 700 250 250 750 350 315 900 250 800 400 600 850 250 500 500 600 900 630 500 400 600 630 750 600 800 800 400 000 000 000 10 500 000 600 250 13 500 11 000 500 600 17 000 14 000 12 000 000 21 000 18 000 15 000 500 26 500 22 000 18 500 " BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) ! -8- Table – No load losses P0 (W) and sound power level (LwA) for Um ≤ 24 kV Rated power C0 D0 B0 Short circuit impedance A0 P0 LwA P0 LwA P0 LwA P0 LwA kVA W dB(A) W dB(A) W dB(A) W dB(A) 50 145 50 125 47 110 42 90 39 100 260 54 210 49 180 44 145 41 160 375 57 300 52 260 47 210 44 250 530 60 425 55 360 50 300 47 315 630 61 520 57 440 52 360 49 400 750 63 610 58 520 53 430 50 500 880 64 720 59 610 54 510 51 630 030 65 860 60 730 55 600 52 630 940 65 800 60 680 55 560 52 800 150 66 930 61 800 56 650 53 000 400 68 100 63 940 58 770 55 250 750 69 350 64 150 59 950 56 600 200 71 700 66 450 61 200 58 000 700 73 100 68 800 63 450 60 500 200 76 500 71 150 66 750 63 NOTE 3.8.2 % P = no load losses L wA = sound power level " Load losses, no load losses and sound power level for U m = 36 kV !Transformers can be requested and offered with LwA lower than the tabled values A “low noise” series with no load losses B036 can be proposed with the LwA from the tabled values of B036, A036, respectively." -9- BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) Table – Load losses Pk36 (W) at 75 °C for Um = 36 kV ! Rated power Bk36 Ak36 Short-circuit impedance kVA W W % 50 250 050 100 950 650 160 550 150 250 500 000 400 900 150 630 500 500 800 400 000 000 10 500 900 250 13 500 11 500 600 17 000 14 500 000 21 000 18 000 500 26 500 22 500 or 4,5 Table – No load losses P036 (W) and sound power level (LwA) for Um = 36 kV Rated power Short-circuit impedance A036 B036 P0 LwA P0 LwA kVA W dB(A) W dB(A) 50 190 52 160 50 800 500 68 300 66 000 700 68 450 67 250 100 70 750 68 600 600 71 200 69 630 300 67 100 65 000 150 73 700 71 500 800 76 200 73 NOTE P = no load losses L wA = sound power level % or 4,5 " BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) 3.9 - 10 - Tolerances and penalties Within the limits of tolerances (EN 60076-1) the application of penalties/bonus with regard to losses is left to the agreement between manufacturer and purchaser at the time of enquiry and order 3.10 Tests 3.10.1 Routine tests EN 60076-1 applies 3.10.2 Type tests EN 60076-1 applies 3.10.3 Special tests EN 60076-1 applies 3.11 Insulation levels and dielectric tests Insulation levels and dielectric tests shall be in accordance with the requirements of EN 60076-3, as further detailed below − High-voltage winding The rated values of the short duration power frequency withstand voltage and of the lightning impulse withstand voltage are given by Table of EN 60076-3, Series − Low-voltage winding According to Table of EN 60076-3, for the normal insulation level, only a short duration power frequency withstand voltage equal to kV, is specified NOTE The values for short duration power frequency withstand and/or for the lightning impulse withstand test between windings and earth are to be stated by the purchaser The most usual values are respectively 10 kV and 30 kV 4.1 Design requirements Type of oil preservation system and degree of sealing The type of oil preservation system and the degree of sealing shall be indicated in the enquiry and order (Table 6) 4.2 Terminal markings Terminal markings should preferably be in accordance with IEC/TR 60616 unless otherwise specified 4.3 Terminations The terminations to be used can be of the following types: a) open type bushings; b) cable boxes (see 3.4.3); c) plug-in type bushings; d) LV busbars The requirements of the different types of terminations should be matter of separate HDs/ENs - 11 - 4.4 BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) Distance between bushings 4.4.1 Distances between high-voltage oil-air bushings The bushings clearance shall meet the requirements of EN 60076-3 For transformers with a highest voltage for equipment equal to 24 kV and lightning impulse 125 kV, the minimum distance between live parts shall be 210 mm and between the highest sheds 120 mm For transformers with a highest voltage for equipment equal to 36 kV, and lightning impulse 170 kV, the minimum distance between live parts shall be 280 mm and between the highest sheds 180 mm However, shorter distances may be agreed, subject to confirmation by test or by service experience NOTE If the user intends to make the connections to the transformer in a way which may reduce the clearances provided by the transformer itself, then this should be brought to attention in the enquiry (EN 60076-3) NOTE When an oil-immersed transformer is specified for operation at an altitude higher than 000 m, clearances shall be designed accordingly It may then be necessary to select bushings designed for higher insulation levels than those specified for the internal insulation of the transformer windings (EN 60076-3) 4.4.2 Preferred distance between centres of low-voltage bushings − For currents up to 250 A 70 mm − For currents above 250 A and up to 000 A 150 mm − For currents above 000 A 165 mm 4.4.3 Cable boxes For transformers in which the terminations are made in cable boxes, EN 50464-2 applies 4.5 Rollers When rollers are fitted, they shall comply with EN 50216-4 Accessories Accessories shall be in accordance with the appropriate Part of EN 50216 The type of oil preservation system and the degree of sealing shall be indicated in the enquiry and order Transformers should normally be fitted with the accessories listed in Table On request by the purchaser or recommended by the manufacturer, additional accessories may be fitted, for instance: − arcing horns on H.V porcelain bushings; − gas and oil actuated relay for liquid immersed transformers with conservator (EN 50216-2); − protective relay for hermetically sealed liquid immersed transformers without gas cushion (EN 50216-3); BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) - 12 - − provision for pad-locking the off-circuit tap-changer; − pulling eyes/lugs Table – Accessories ! Accessories Free breathing Hermetically sealed Gas cushion Conservator Gas cushion Totally filled Rating plate X X X X earthing terminals X X X X Lifting lugs X X X X Oil level indicator X X a ab Filling hole and plug X X X X a X a a Dehydrating breather X X Thermometer pocket (EN 50216-4) X X a a Drain and sampling plug or valve a If requested b An equivalent device may be provided " Efficiency and voltage drop (at reference temperature) 6.1 Efficiency The efficiency of a power transformer is given for any load condition by the ratio between the out power (P2) and the input power (P1) η = 100 ⋅ P2 (%) P1 Because of the difficulty to determine the efficiency by direct measurements, it can be evaluated conventionally through the guaranteed or measured losses as follows  η = 100 ⋅  −  α ⋅ Pcc + P0 α ⋅ S + α ⋅ Pcc + P0   (%)  where Pcc = load loss at rated current and reference temperature; P0 = no load loss at rated voltage and frequency; S = rated power; α = load factor (p.u.) - 13 - 6.2 BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) Voltage drop ( u%) The voltage drop for any load condition (secondary current and power factor) is given by the following relation: Δu % = ( I / I n ) ⋅ (R % ⋅ cos ϕ + X % ⋅ sin ϕ ) + (1 / 200 ) ⋅ {(I / I n ) ⋅ ( X % ⋅ cos ϕ − R % ⋅ sin ϕ )} where R% = load loss expressed in % of rated power; X% = reactive power expressed in % of rated power; I2 = load secondary current (A); I2n = secondary rated current (A); (I2 / I2n) = load factor; ϕ2 = phase angle between secondary voltage and current BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) - 14 - Annex A (informative) Capitalisation evaluation A transformer produces losses due to the magnetisation of the core (no load losses P0) and due to the current carrying windings (load losses Pk) No load losses are generated whenever the transformer is energised and usually are considered for 760 h per year They are independent of the load while load losses relate to the square of the current (Pk ~I²) The sum of both losses represents a loss of energy translated into heat which has to be dissipated by the cooling system of the transformer Since energy has a certain cost, it is important to be aware of the financial value of the losses generated during the lifetime of the transformer in addition to the initial purchase cost The loading profile, the transformer losses and the energy cost should be taken into account in order to select the optimal no load losses and load losses The losses tabled in this standard represent nowadays European practice However, this evaluation may change over time and can be different in each country or for each user, depending on local investment or energy policies Therefore, transformers can be requested or offered with no load losses and/or load losses different from those tabled in this standard to satisfy particular requirements The sum of purchase cost and energy cost (load losses and no load losses) is called capitalised cost and represents an important part of the investment for the purchaser This analysis may be done by using a capitalisation formula as follows: C C = C T + A ⋅ P0 + B ⋅ PK where CC = capitalised cost; CT = purchase cost of transformer; A = value indicated by the purchaser in the enquiry expressed in local currency per watt (e.g €/W) corresponding to no load losses; P0 = guaranteed no load losses in watts; B = value indicated by the purchaser in the enquiry expressed in local currency per watt (e.g €/W) corresponding to load losses; Pk = guaranteed load losses in watts - 15 - BS EN 50464-1:2007+A1:2012 EN 50464-1:2007+A1:2012 (E) Bibliography EN 50180 Bushings above kV up to 36 kV and from 250 A to 3,15 kA for liquid filled transformers EN 50181 Plug-in type bushings above kV up to 36 kV and from 250 A to 1,25 kA for equipment other than liquid filled transformers EN 50386 Bushings up to kV and from 250 A to kA, for liquid filled transformers EN 50387 Busbar bushings up to kV and from 1,25 kA to kA, for liquid filled transformers BS EN 50464-1:2007 +A1:2012 BSI - British Standards Institution BSI is the independent national body responsible for preparing British Standards It presents the UK view on standards in Europe and at the international level It is incorporated by Royal Charter Revisions British Standards are updated by amendment or revision Users of British Standards should make sure that they possess the latest amendments or editions It is the constant aim of BSI to improve the quality of our products and services We would be grateful if anyone finding an inaccuracy or ambiguity while using this British Standard would inform the Secretary of the technical committee responsible, the identity of which can be found on the inside front cover Tel: +44 (0)20 8996 9000 Fax: +44 (0)20 8996 7400 BSI offers members an individual updating service called PLUS which ensures that subscribers automatically receive the latest editions of standards Buying standards Orders for all BSI, international and foreign standards publications should be addressed to Customer Services Tel: +44 (0)20 8996 9001 Fax: +44 (0)20 8996 7001 Email: orders@bsigroup.com You may also buy directly using a debit/credit card from the BSI Shop on the Website http://www.bsigroup.com/shop In response to orders for international standards, it is BSI policy to supply the BSI implementation of those that have been published as British Standards, unless otherwise requested Information on standards BSI provides a wide range of information on national, European and international standards through its Library and its Technical Help to Exporters Service Various BSI electronic information services are also available which give details on all its products and services Contact Information Centre Tel: +44 (0)20 8996 7111 Fax: +44 (0)20 8996 7048 Email: info@bsigroup.com Subscribing members of BSI are kept up to date with standards developments and receive substantial discounts on the purchase price of standards For details of these and other benefits contact Membership Administration Tel: +44 (0)20 8996 7002 Fax: +44 (0)20 8996 7001 Email: membership@bsigroup.com Information regarding online access to British Standards via British Standards Online can be found at http://www.bsigroup.com/BSOL Further information about BSI is available on the BSI website at http:// www.bsigroup.com Copyright BSI Group Headquarters 389 Chiswick High Road, London, W4 4AL, UK Tel +44 (0)20 8996 9001 Fax +44 (0)20 8996 7001 www.bsigroup.com/ standards Copyright subsists in all BSI publications BSI also holds the copyright, in the UK, of the publications of the international standardization bodies Except as permitted under the Copyright, Designs and Patents Act 1988 no extract may be reproduced, stored in a retrieval system or transmitted in any form or by any means – electronic, photocopying, recording or otherwise – without prior written permission from BSI This does not preclude the free use, in the course of implementing the standard, of necessary details such as symbols, and size, type or grade designations If these details are to be used for any other purpose than implementation then the prior written permission of BSI must be obtained Details and advice can be obtained from the Copyright and Licensing Manager Tel: +44 (0)20 8996 7070 Email: copyright@bsigroup.com

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