1、BRITISH STANDARDBS EN 50482:2008Instrument transformers Three-phase inductive voltage transformers having Umup to 52 kVICS 17.220.20g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50
2、g51g60g53g44g42g43g55g3g47g36g58BS EN 50482:2008This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 May 2008 BSI 2008ISBN 978 0 580 56558 8National forewordThis British Standard is the UK implementation of EN 50482:2008. It supersedes BS 7729:
3、1994 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee PEL/38, Instrument 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 provi
4、sions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.Amendments/corrigenda issued since publicationDate CommentsEUROPEAN STANDARD EN 50482 NORME EUROPENNE EUROPISCHE NORM January 2008 CENELEC European
5、Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2008 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CEN
6、ELEC members. Ref. No. EN 50482:2008 E ICS 17.220.20 Supersedes HD 587 S1:1993English version Instrument transformers - Three-phase inductive voltage transformers having Umup to 52 kV Transformateurs de mesure - Transformateurs inductifs de tension triphass avec Umjusqu 52 kV Messwandler - Dreiphasi
7、ge Spannungswandler mit Umbis 52 kV This European Standard was approved by CENELEC on 2007-09-01. 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. U
8、p-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 translatio
9、n 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
10、, 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. EN 50482:2008 2 Foreword This European Standard was prepared by the Technical
11、Committee CENELEC TC 38X, Instrument transformers. The text of the draft was submitted to the formal vote and was approved by CENELEC as EN 50482 on 2007-09-01. This European Standard supersedes HD 587 S1:1993. It is to be used in conjunction with EN 60044-2:1999. The following dates were fixed: lat
12、est date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2008-09-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2010-09-01 _ BS EN 50482:2008 3 EN 50482:2008 Contents 1
13、 General. 5 1.1 Scope 5 1.2 Normative references 5 2 Definitions. 5 3 General requirements 5 4 Normal and special service conditions. 5 5 Ratings 5 5.1 Standard values of rated voltages 5 5.2 Standard values of rated output. 6 5.3 Standard values of rated voltage factor 6 5.4 Limits of temperature r
14、ise 6 6 Design requirements . 7 6.1 Insulation requirements . 7 6.2 Short-circuit withstand capability 8 7 Classification of tests. 8 8 Type tests . 8 8.1 Temperature-rise tests. 8 8.2 Short-circuit withstand capability test . 8 8.3 Impulse test on primary winding. 8 8.4 Wet test for outdoor type tr
15、ansformers. 9 9 Routine tests. 9 9.1 Verification of terminal markings 9 9.2 Power frequency tests on primary winding and partial discharge measurement 9 9.3 Power-frequency tests between section and on secondary windings 11 10 Special test . 11 11 Markings . 11 11.1 Rating plate and markings . 11 1
16、1.2 Terminal markings. 11 12 Accuracy requirements for three-phase inductive measuring voltage transformers. 12 12.1 Accuracy class designation for measuring voltage transformers. 12 12.2 Limits of voltage error and phase displacement for measuring voltage transformers. 12 12.3 Type test for accurac
17、y of measuring voltage transformers 12 12.4 Routine test for accuracy of measuring voltage transformers . 12 12.5 Markings of the rating plate of three-phase measuring voltage transformer 12 13 Additional requirements for three-phase inductive protective voltage transformers . 12 13.1 Accuracy class
18、 designation for protective voltage transformers 12 13.2 Limits of voltage error and phase displacement for protective voltage transformers 12 13.3 Rated voltages for secondary windings intended to produce a residual voltage 12 13.4 Output for secondary windings intended to produce a residual voltag
19、e. 12 13.5 Accuracy class for secondary windings intended to produce a residual voltage 13 13.6 Type test for protective voltage transformers 13 13.7 Routine test for protective transformers . 14 13.8 Markings of the rating plate of a three-phase protective voltage transformer 14 Bibliography . 21 B
20、S EN 50482:2008EN 50482:2008 4 Figures Figure 1 Three-phase transformer with a single secondary 15 Figure 2 Three-phase transformer with two secondaries 15 Figure 3 Three-phase transformer with one multi-tap secondary 16 Figure 4 Three-phase transformer with one residual voltage winding . 16 Figure
21、5 Circuit for accuracy test on a voltage transformer having a rated voltage factor of 1,5 17 Figure 6 Circuit for accuracy test on a voltage transformer having a rated voltage factor of 1,9 17 Figure 7 Circuit for accuracy test on the residual voltage winding of a voltage transformer having a rated
22、voltage factor not exceeding 1,5 18 Figure 8 Circuit for accuracy test on the residual voltage winding of a voltage transformer having a rated voltage factor not exceeding 1,9 18 Figure 9 Alternative circuit for accuracy test on the residual voltage winding of a voltage transformer having a rated vo
23、ltage factor of 1,9 . 19 Figure 10 Test circuit for partial discharge measurement of a three-phase earthed voltage transformer 19 Figure 11 Test circuit for partial discharge measurement of a three-phase unearthed voltage transformer 20 Figure 12 Example of a calibration circuit used during the meas
24、urement of partial discharge of a three-phase voltage transformer . 20 Table Table 1 Permissible partial discharge levels for various neutral earthing system and test voltages 7 BS EN 50482:2008 5 EN 50482:2008 1 General 1.1 Scope This European Standard specifies the requirements and tests for new t
25、hree-phase voltage transformers with Umup to 52 kV and frequencies from 15 Hz to 100 Hz, for use with electrical instruments or electrical protective devices. NOTE Single-phase voltage transformers connected in a three-phase bank are not covered in this document. 1.2 Normative references The followi
26、ng 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 60044-2:1999, Instrument transformers Part 2: Inductive v
27、oltage transformers (IEC 60044-2:1997, mod.) EN 60270:2001, High-voltage test techniques Partial discharge measurements (IEC 60270:2000) HD 588.1 S1:1991, High-voltage test techniques Part 1: General definitions and test requirements (IEC 60060-1:1989 + corr. March 1990) 2 Definitions Clause 2 of EN
28、 60044-2:1999 is applicable with the following additions: 2.3 Additional definitions for three-phase inductive voltage transformers 2.3.1 three-phase voltage transformer a voltage transformer which has three line-to-neutral primary windings the neutral point of which can be earthed or unearthed and
29、in which one or more of the three line-to-neutral secondary windings can be connected for three-phase operation or residual voltage operation 2.3.2 rated output of a three-phase voltage transformer the per phase value of the apparent power (in volt-amperes at a specified power factor) that a three-p
30、hase voltage transformer is intended to supply to the secondary circuit, at the rated secondary voltage and with rated per-phase burden connected to it 3 General requirements Clause 3 of EN 60044-2:1999 applies. 4 Normal and special service conditions Clause 4 of EN 60044-2:1999 applies. 5 Ratings 5
31、.1 Standard values of rated voltages 5.1.1 Rated primary voltages The standard values of rated line-to-line primary voltage of three-phase voltage transformer shall be one of the values of nominal system voltage designated by EN 60044-2:1999. NOTE The performance of a voltage transformer as a measur
32、ing or protection transformer is based on the rated primary voltage, whereas the rated insulation level is based on one value of the highest voltages for equipment of EN 60071. BS EN 50482:2008EN 50482:2008 6 5.1.2 Rated secondary voltages The rated line-to-line secondary voltage shall be chosen acc
33、ording to practice at the location where the transformer is to be used. The values given below are considered standard values for three-phase voltage transformers: 100 V and 110 V; 200 V, for extended secondary circuits. NOTE Whenever possible, the rated transformation ratio should be a simple value
34、. If one of the following values: 10 12 15 20 25 30 40 50 60 80 and their decimal multiples is used for the rated transformation ratio together with one of the rated secondary voltages of this subclause, the majority of the standard values of nominal system voltage of IEC 60038 will be covered. 5.1.
35、3 Rated secondary voltages for residual windings The rated secondary voltages of windings intended to be connected in broken-delta with similar windings to produce a residual voltage are given in 13.3. 5.2 Standard values of rated output The standard values of rated output per phase at a power facto
36、r of 0,8 lagging, expressed in volt-amperes, are: 10 15 25 30 50 75 100 150 200 VA The underlined values are preferred values. NOTE For a given transformer, provided one of the values of rated output is standard and associated with a standard accuracy class, the declaration of other rated outputs, w
37、hich may be non-standard values but associated with other standard accuracy classes, is not precluded. 5.3 Standard values of rated voltage factor Subclause 5.3 of EN 60044-2:1999 applies. 5.4 Limits of temperature rise Unless otherwise specified below the temperature rise of a voltage transformer a
38、t the specified voltage, at the rated frequency and at the rated burden or at the highest burden, if there are several rated burden, at any power factor between 0,8 lagging and unity, shall not exceed the appropriate value given in Table 3 of EN 60044-2:1999. a) All three-phase transformers, irrespe
39、ctive of voltage factor (VF) and time rating, shall be capable of operating continuously with a balanced three-phase voltage of 1,2 times rated primary voltage. The steady state temperature rise shall not exceed the limits given in Table 3 of EN 60044-2:1999. b) Three-phase earthed transformers havi
40、ng a voltage factor of 1,5 for 30 s or 1,9 for 30 s shall after the application of 1,2 times rated primary voltages for sufficient time to reach stable thermal conditions, be capable of operating with a balanced three-phase voltage of respectively 0,866 or 1,1 times the rated primary voltage applied
41、 for 30 s, one line terminal of the primary winding being connected to the neutral of that winding. The temperature rise shall not exceed by more than 10 K the value specified in Table 3 of EN 60044-2:1999. c) Three-phase earthed transformers having a voltage factor of 1,9 for 8 h shall after the ap
42、plication of 1,2 times rated primary voltage for sufficient time to reach stable thermal conditions, be capable of operating with a balanced three-phase voltage of 1,1 times rated line-to-line voltage applied for 8 h, one line terminal of the primary winding being connected to the neutral point of t
43、he winding. The temperature rise shall not exceed by more than 10 K the value specified in Table 3 of EN 60044-2:1999. Table 3 of EN 60044-2:1999 as well as the text and the notes, except a), b), and c) above apply. BS EN 50482:2008 7 EN 50482:2008 6 Design requirements 6.1 Insulation requirements T
44、hese requirements apply to all types of inductive voltage transformers. For gas-insulated voltage transformers supplementary requirements may be necessary (presently under consideration in IEC/TC 38). 6.1.1 Rated insulation levels, primary windings The rated insulation level shall be one of those gi
45、ven in Table 4 of EN 60044-2:1999. 6.1.2 Other requirements for primary winding insulation 6.1.2.1 Power-frequency withstand voltage Subclause 6.1.2.1 of EN 60044-2:1999 applies. 6.1.2.2 Power-frequency withstand voltage for earthed terminal Subclause 6.1.2.2 of EN 60044-2:1999 applies. 6.1.2.3 Part
46、ial discharges Partial discharge requirements are applicable to inductive three-phase voltage transformers having Umgreater than or equal to 7,2 kV. The partial discharge level shall not exceed the limits specified in Table 1, at the partial discharge test voltages specified in the same table after
47、prestressing according to the procedures of 9.2.3.3. Table 1 Permissible partial discharge levels for various neutral earthing system and test voltages Type of network earthing Type of voltage transformer Single-phase partial discharge test voltage Permissible partial discharge level pC Earthed tran
48、sformer Um1,2 Um/ 3 50 20 Earthed neutral system VF 1,5 Unearthed transformer Um1,2 Um/ 3 50 20 Earthed transformer Um1,2 Um/ 3 50 20 Isolated or non-effectively earthed neutral system VF 1,5 Unearthed transformer Um1,2 Um/ 3 50 20 6.1.2.4 Chopped lighting-impulse Subclause 6.1.2.4 of EN 60044-2:199
49、9 applies. 6.1.3 Between-section insulation requirements Subclause 6.1.3 of EN 60044-2:1999 applies. 6.1.4 Insulation requirements for secondary windings Subclause 6.1.4 of EN 60044-2:1999 applies. BS EN 50482:2008EN 50482:2008 8 6.1.5 Requirements for external insulation 6.1.5.1 Pollution For outdoor inductive voltage transformers, with ceramic insulators, susceptible to contamination, the creepage distances for given pollution levels are given in Table 8 of EN
