1、BRITISH STANDARD BS EN 50336:2002 Bushings for transformers and reactor cable boxes not exceeding 36 kV The European Standard EN 50336:2002 has the status of a British Standard ICS 29.080.20; 29.180 BS EN 50336:2002 This British Standard, having been prepared under the direction of the Electrotechni
2、cal Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 10 October 2002 BSI 10 October 2002 ISBN 0 580 40555 9 National foreword This British Standard is the official English language version of EN 50336:2002. The UK participation
3、 in its preparation was entrusted by Technical Committee PEL/36, Insulators for power systems, to Subcommittee PEL/36/1, Bushing insulators which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The Brit
4、ish Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Onl
5、ine. 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 does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsi
6、ble international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover,
7、 the EN title page, pages 2 to 14, an inside back cover and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEAN STANDARD EN 50336 NORME EUROPENNE EUROPISCHE NORM June 2002 CENE
8、LEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2002 CENELEC - All rights of exploitation in any form and by any means reserved worl
9、dwide for CENELEC members. Ref. No. EN 50336:2002 E ICS 29.080.20; 29.180 English version Bushings for transformers and reactor cable boxes not exceeding 36 kV Traverses pour botes cbles de transformateurs et dinductances ne dpassant pas 36 kV Durchfhrungen fr Kabelanschluss- ksten von Transformator
10、en und Drosselspulen bis 36 kV This European Standard was approved by CENELEC on 2001-12-04. 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-
11、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 und
12、er 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, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary,
13、Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United Kingdom.EN 50336:2002 - 2 - Foreword This European Standard was prepared by the Technical Committee CENELEC TC 36A, Insulated bushings. The text of the draft was submitted to th
14、e formal vote and was approved by CENELEC as EN 50336 on 2001-12-04. 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) 2002-12-01 - latest date by which the national standards
15、 conflicting with the EN have to be withdrawn (dow) 2004-12-01 _- 3 - EN 50336:2002 Contents Page 1 Scope . 4 2 Normative references . 4 3 Definitions. 4 4 Requirements . 5 4.1 Rating 5 4.1.1 Standard values of rated voltage (U r ) 5 4.1.2 Standard values of rated current (I r ) 5 4.2 Compliance . 5
16、 4.2.1 General - Ceramic bushings . 5 4.2.2 General - Resin insulated bushings. 6EN 50336:2002 - 4 - 1 Scope This standard is applicable to insulated bushings for use in air insulated, shroud insulated and fully insulated cable boxes for liquid filled transformers and reactors for rated voltages up
17、to 36 kV, and rated currents up to 4 000 A at frequencies from 15 Hz to 60 Hz. 2 Normative references This European Standard incorporates, by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publication
18、s are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references, the latest edition of the publication referred to applies (including amendme
19、nts). EN 60137 1996 Insulated bushings for alternating voltages above 1 kV (IEC 60137:1995) EN 61099 1992 Specification for unused synthetic organic esters for electrical purposes (IEC 61099:1992) EN 22768-1 1993 General tolerances - Part 1: Tolerances for linear and angular dimensions without indiv
20、idual tolerance indications HD 329 S1 1977 Tests on hollow insulators for use in electrical equipment (IEC 60233:1974) HD 428.2.1 S1 1994 Three phase oil-immersed distribution transformers 50 Hz, from 50 kVA to 2,5 MVA with highest voltage for equipment not exceeding 36 kV - Part 2: Distribution tra
21、nsformers with cable boxes on the high-voltage and/or low-voltage side - Section 1: General requirements HD 565 S1 1993 Specifications for silicone liquids for electrical purposes (IEC 60836:1988) IEC 60296 1992 Specification for unused mineral insulating oils for transformers and switchgear 3 Defin
22、itions For the purposes of this standard the following definitions apply: 3.1 air insulated cable box a metallic cable box designed to protect the ends of the cables and bushings, providing a weatherproof enclosure with a minimum rating of IP54. An air filled cable box within which the cable cores a
23、re electrically terminated by stress control appropriate to the cable design and voltage; air being the sole insulation for the terminal connections 3.2 shroud insulated cable box an air filled cable box as in 3.1 but within which the cable cores are terminated with local insulation enhancement, e.g
24、. phase barrier, bushing protection or taping 3.3 fully insulated cable box a cable box where those parts of the termination and bushing within the enclosure including live metal parts and cable cores are insulated by liquid or compound suitable for the appropriate system voltage. The box shall be s
25、uitably sealed to contain the liquid or compound and allow for their expansion due to temperature changes- 5 - EN 50336:2002 3.4 ceramic, glass or analogous inorganic material bushing bushing in which the major insulation consists of a ceramic, glass or analogous inorganic material 3.5 cast or mould
26、ed resin insulated bushing bushing in which the major insulation consists of a cast or moulded organic material with or without an inorganic filler. 4 Requirements Bushings covered by this specification are suitable for operation with one end fully immersed in an insulating liquid and the other end
27、either fully immersed in an insulating liquid; or with shrouded insulation in air; or in air but not exposed to external atmospheric conditions. All other requirements shall be as specified herein. 4.1 Rating 4.1.1 Standard values of rated voltage (U r ) The value of U rof a bushing shall be chosen
28、from the standard values of the highest voltage for transformers and reactors U mgiven below in kilovolts: 12 - 24 - 36 NOTE 1 For ceramic bushings where U m is 1,1 then U r 12 is to be used where U m is 3,6 then U r 12 is to be used where U m is 7,2 then U r 12 is to be used where U m is 17,5 then
29、U r 24 is to be used. NOTE 2 For resin insulated bushings the permitted highest rated voltages U r are Liquid / air or air / air 1,1 Liquid / liquid 12. 4.1.2 Standard values of rated current (I r ) The value I r of a bushing shall be chosen from the standard values given below in amperes: 250 - 400
30、 - 630 - 800 - 1 250 - 1 600 - 2 000 - 2 500 - 3 150 - 4 000 4.2 Compliance 4.2.1 General - Ceramic bushings Ceramic bushings shall meet the requirements for both type and routine tests laid out in EN 60137 and in addition the following shall also apply: Bushings shall be capable of sealing a liquid
31、 filled chamber. The design of 24 kV and 36 kV bushings shall be such that free entry of liquid is allowed into the space between the conductor and the ceramic. In such instances the sealing integrity of the bushing shall be maintained. The conductor size, material and nut and thread dimensions of t
32、he bushing terminal for the appropriate current rating shall comply with Table 1.EN 50336:2002 - 6 - The ceramic insulators used shall be to Figures 1 or 2. The ceramic insulator shall be sound, free from defects, thoroughly vitrified and smoothly glazed. The glaze, which shall not be depended upon
33、for insulation, shall, as far as practicable, cover all surfaces except the flat surfaces of the flange and the ends of the ceramic. The preferred glaze colour is a uniform shade of brown. Other glaze colours are acceptable subject to agreement between purchaser and manufacturer. Tolerances on dimen
34、sions for Figures 1 and 2 are as per HD 329 unless otherwise specified. The prefered value for the mounting hole is a diameter of (D 2+ 3 mm). Each ceramic insulator shall be legibly and reasonably permanently marked with the name or trade mark of the manufacturer and the month and year of manufactu
35、re. These marks shall be printed, clearly legible after glazing and firing and not appear on the flange faces or end surfaces. All ceramic insulators shall be subjected to tests in accordance with HD 329. Bushing clamps shall be in accordance with Figure 3 as appropriate, and be fitted to the transf
36、ormer side of the bushing. Bushing terminal arrangements for the cable box side are shown in Figures 5 and 6. Terminal arrangements for the transformer side are shown in Figure 7. Tolerances on dimensions for Figures 3, 5, 6 105 C ; ambient temperature. The duration of each stage shall be between 20
37、 min and 30 min. The cycle shall be repeated ten times consecutively. On completion the bushing shall not exhibit signs of cracking and shall withstand the liquid leakage, air leakage and over voltage tests detailed below. 4.2.2.2 Liquid leakage sample test Each resin insulated bushing selected for
38、sample testing shall be subjected to a liquid leakage test for 6 hours. The liquid shall comply with the requirements of IEC 60296, HD 565 and EN 61099 and shall be maintained at 75 C with an applied pressure of (1 0,1) bar. The pressure shall be applied to the transformer side of the bushing with t
39、he other end exposed to atmosphere. At the conclusion of this test, no leakage or liquid ingress into normally liquid free spaces shall have occurred. This sample test shall be carried out on at least one assembly from each batch or 2 % of all units manufactured in each batch, whichever is greater.
40、4.2.2.3 Air leakage routine test Each resin insulated bushing shall be subjected to an air leakage test for 15 min at a pressure of (1,5 0,1) bar on the transformer side of the bushing with the other side exposed to atmosphere. At the conclusion of this test no leakage of air shall have occurred. 4.
41、2.2.4 Over voltage routine test Each resin insulated bushing shall withstand a dry power frequency withstand voltage test of 28 kV for 1 min between adjacent conductors and between conductors and earth. 4.2.2.5 Routine partial discharge test If the resin insulated bushing is to be used at voltages g
42、reater than 1,1 kV then each bushing shall be subjected to a partial discharge test in accordance with EN 60137.EN 50336:2002 - 8 - Transformer side Cable box side Insulator type U r kV L 1 mm L 2 mm L 3 mm L 4 mm D 1 mm D 2 mm D 3 mm D 4 mm 1 12 293 102 172 19 82 57 47 18 2 12 295 102 172 21 107 80
43、 70 45 3 12 295 102 172 21 117 89 80 50 4 24 406 135 250 21 107 80 70 45 5 24 410 135 250 21 117 89 80 50 6 36 553 178 250 25 159 114 102 64 Figure 1 - Ceramic insulators for cable boxes as defined in 3.1 L 1min- 9 - EN 50336:2002 Transformer side Cable box side Insulator type U r kV L 1 mm L 2 mm L
44、 3 mm L 4 mm D 1 mm D 2 mm D 3 mm D 4 mm7 12 223 102 102 19 82 57 47 188 12 225 102 102 21 107 80 70 459 12 225 102 102 21 117 89 80 50 10 24 291 135 135 21 107 80 70 45 11 24 291 135 135 21 117 89 80 50 12 36 381 178 178 25 159 114 102 64 13 12 229 102 102 25 168 127 114 70 Figure 2 - Ceramic insulators for cable boxes as defined in 3.2 and 3.3 L 1min
