1、BRITISH STANDARD BS EN 61643-331: 2003 Components for low-voltage surge protective devices Part 331: Specification for metal oxide varistors (MOV) The European Standard EN 61643-331:2003 has the status of a British Standard ICS 31.040 BS EN 61643-331:2003 This British Standard was published under th
2、e authority of the Standards Policy and Strategy Committee on 22 August 2003 BSI 22 August 2003 ISBN 0 580 42491 X National foreword This British Standard is the official English language version of EN 61643-331:2003. It is identical with IEC 61643-331:2003. The UK participation in its preparation w
3、as entrusted by Technical Committee PEL/37, Surge arresters, to Subcommittee PEL/37/2, Surge arresters Low voltage, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which impl
4、ement 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 Online. This publication do
5、es 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 responsible international/Europe
6、an 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, the EN title page, page
7、s 2 to 18, 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 61643-331 NORME EUROPENNE EUROPISCHE NORM July 2003 CENELEC European Committ
8、ee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2003 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC me
9、mbers. Ref. No. EN 61643-331:2003 E ICS 31.040 English version Components for low-voltage surge protective devices Part 331: Specification for metal oxide varistors (MOV) (IEC 61643-331:2003) Composants pour parafoudres basse tension Partie 331: Spcifications pour les varistances oxyde mtallique (MO
10、V) (CEI 61643-331:2003) Bauelemente fr berspannungsschutzgerte fr Niederspannung Teil 331: Festlegungen fr Metalloxidvaristoren (IEC 61643-331:2003) This European Standard was approved by CENELEC on 2003-07-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipu
11、late 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 Standar
12、d 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
13、 electrotechnical committees of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Lithuania, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United Kingdom. Foreword The text of document 37B/67/FD
14、IS, future edition 1 of IEC 61643-331, prepared by SC 37B, Specific components for surge arresters and surge protective devices, of IEC TC 37, Surge arresters, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61643-331 on 2003-07-01. The following dates were fixed: la
15、test date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2004-04-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2006-07-01 Annexes designated “normative“ are part of t
16、he body of the standard. In this standard, annexes A and ZA are normative. Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 61643-331:2003 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliogr
17、aphy, the following notes have to be added for the standards indicated: IEC 60060-1 NOTE Harmonized as HD 588.1 S1:1991 (not modified). IEC 61000-4-5 NOTE Harmonized as EN 61000-4-5:1995 (not modified). IEC 61180-1 NOTE Harmonized as EN 61180-1:1994 (not modified). _ Page2 EN61643331:200361643-331 I
18、EC:2003 3 CONTENTS 1 Scope.4 2 Normative references.4 3 Parametric terms, letter symbols and definitions.5 3.1 Ratings5 3.2 Characteristics6 3.3 Circuit symbol.7 4 Service conditions 7 4.1 Normal service conditions .7 4.2 Abnormal service conditions8 5 Basic function and MOV component description .8
19、 6 Identification.9 6.1 Generalities.9 6.2 Functional and constructive characteristics .9 6.3 Manufacturing inspections.9 7 Marking9 8 Testing and measuring methods.10 8.1 Standard design test criteria10 8.2 Test conditions10 8.3 Ratings10 8.4 Electrical characteristics11 8.5 Dependability12 9 Fault
20、 and failure mode13 9.1 Degradation fault mode .13 9.2 Fault-mode determination of rating test failures.13 Annex A (normative) MOV testing for IEC 61643-1 surge protective devices14 Annex ZA (normative) Normative references to international publications with their corresponding European publications
21、 .17 Bibliography18 Figure 1 V-I characteristic of a MOV 6 Figure 2 Test circuit for impulse peak current clamping voltage (V C ) at peak impulse current (I P ) 10 Figure 3 Test circuit for measuring standby current11 Figure 4 Test circuit for measuring nominal varistor voltage (V N ) .12 Page3 EN61
22、643331:200361643-331 IEC:2003 4 COMPONENTS FOR LOW-VOLTAGE SURGE PROTECTIVE DEVICES Part 331: Specification for metal oxide varistors (MOV) 1 Scope This part of IEC 61643 is a test specification for metal oxide varistors (MOV), which are used for applications up to 1 000 V a.c. or 1 500 V d.c. in po
23、wer line, or telecommunication, or signalling circuits. They are designed to protect apparatus or personnel, or both, from high transient voltages. This specification applies to MOVs having two electrodes and does not deal with hybrid devices. This specification also does not apply to mountings and
24、their effect on the MOVs characteristics. Characteristics given apply solely to the MOV mounted only in the ways described for the tests. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited app
25、lies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60068-1:1988, Environmental testing Part 1: General and guidance IEC 60068-2-6:1995, Environmental testing Part 2: Tests Test Fc: Vibration (sinusoidal) IEC 60068-2-14:1984, Environmen
26、tal testing Part 2: Tests Test N: Change of temperature IEC 60068-2-20:1979, Environmental testing Part 2: Tests Test T: Soldering IEC 60068-2-29:1987, Environmental testing Part 2: Tests Test Eb and guidance: Bump IEC 60068-2-52:1996, Environmental testing Part 2: Tests Test Kb: Salt mist, cyclic (
27、sodium, chloride solution) IEC 60068-2-78:2001, Environmental testing Part 2-78: Tests Test Cab: Damp heat/ steady state IEC 61643-1:1998, Surge protected devices connected to low-voltage power distribution systems Part 1: Performance requirements and testing methods Page4 EN61643331:200361643-331 I
28、EC:2003 5 3 Parametric terms, letter symbols and definitions 3.1 ratings either a limiting capability or a limiting condition beyond which damage to the MOV may occur NOTE A limiting condition may be either a maximum or a minimum. 3.1.1 single-pulse peak current I TMrated maximum value which may be
29、applied for a single impulse of specified waveform, without causing MOV failure NOTE Unless otherwise specified, an 8/20 s waveshape is used. In some cases, the rated line voltage may also be applied. 3.1.2 multiple-pulse peak current I TSMrated maximum value which may be applied for repetitive appl
30、ications of an impulse of specified waveform, without causing MOV failure NOTE Unless otherwise specified, an 8/20 s waveform is used. 3.1.3 multiple-pulse peak-current derating against pulse width graphical representation of rated multiple-pulse peak current against rectangular pulse width for diff
31、erent numbers of impulses NOTE Typically, curves are provided for indefinite, 10 6 , 10 5 , 10 4 , 10 3 , 10 2 and 10 pulses together with a single- pulse curve. 3.1.4 temperature derating curve graphical representation of parameter derating against temperature NOTE Typical parameters are rated volt
32、age, impulse current, energy and average power dissipation. 3.1.5 single-pulse maximum energy W TMrated maximum value which may be absorbed for a single pulse of a specified waveform NOTE Unless otherwise specified, 2 ms rectangular pulse is used (IEC 60060). 3.1.6 maximum continuous voltage V M(see
33、 Figure 1) voltage that may be applied continuously at a specified temperature 3.1.6.1 maximum continuous a.c. voltage V M(AC)r.m.s. a.c. sinusoidal voltage (less than 5 % total harmonic distortion) that may be applied continuously at a specified temperature 3.1.6.2 maximum continuous d.c. voltage V
34、 M(DC)d.c. voltage that may be applied continuously at a specified temperature Page5 EN61643331:200361643-331 IEC:2003 6 3.1.7 maximum continuous power dissipation P Maverage power that may be continuously dissipated for a given life expectancy 3.2 characteristics inherent and measurable properties
35、of an MOV 3.2.1 standby current I Dimpulse current of defined amplitude and waveshape NOTE 1 It is also called leakage current. NOTE 2 In Figure 1, this is the specified peak pulse current when measuring the MOV clamping voltage V C(see 3.2.3)3.2.2 nominal varistor voltage V Nvoltage across the MOV
36、measured at a specified pulsed current (I N ), of specific duration (see Figure 1) NOTE The MOV manufacturer specifies the current. Otherwise, 1 mA is normally used. The pulse duration should be less than 40 ms, unless otherwise specified. In general, nominal value 10 % is specified by the manufactu
37、rer. 3.2.3 clamping voltage V Cpeak voltage across the MOV measured under conditions of a specified peak pulse current (I P ) and specified waveform (see Figure 1) I TM i +i +v v I P I N I D V M V N V C IEC 1535/03Figure 1 V-I characteristic of a MOV Page6 EN61643331:200361643-331 IEC:2003 7 3.2.4 c
38、apacitance C Vcapacitance across the MOV measured at a specified frequency and voltage 3.2.5 equivalent series inductance L Veffective inductance measured across the MOV terminals at a given frequency 3.2.6 pulse current I N rectangular pulse current of defined amplitude and duration 3.3 circuit sym
39、bol symbol for the MOV : 4 Service conditions 4.1 Normal service conditions 4.1.1 Environmental conditions 4.1.1.1 Operating and storage temperature ranges Normal range: 5 C to +55 C Extended range: 40 C to +85 C 4.1.1.2 Altitude or atmospheric pressure range The altitude of air pressure is within 8
40、6 kPa to 106 kPa (refer to IEC 60068-1). 4.1.1.3 Humidity Relative humidity under the operating temperature conditions shall be less than 93 % at 25 C. Refer to IEC 60068-1 and IEC 60068-2-78). 4.1.1.4 Mechanical shock and vibration The purpose of this test is to determine mechanical weakness and/or
41、 degradation in specified performance and to use the information, in conjunction with the relevant specification, to decide whether a component is acceptable or not (refer to IEC 60068-2-6). 4.1.2 MOV physical properties 4.1.2.1 Solvent resistance To determine the resistance of the MOV against chemi
42、cal solvent (the manufacturer shall provide the data if it is required). Page7 EN61643331:200361643-331 IEC:2003 8 4.1.2.2 Solderability To determine the solderability of the area on wire and tag terminations that are required to be wetted by solder and, if required, to determine any de-wetting. Ref
43、er to Clause 4 of IEC 60068-2-20. 4.1.3 System conditions 4.1.3.1 Nominal system frequencies The frequency of the supply mains is between 48 Hz and 62 Hz a.c. or d.c. 4.1.3.2 Maximum continuous system voltage This depends on the system of the country and differs from regional power conditions. It is
44、 normally considered to be 10 % higher than nominal system voltage. 4.2 Abnormal service conditions MOVs subject to other than normal application or service conditions may require special consideration in design, manufacture or application. The use of this standard in case of abnormal service condit
45、ions is subject to agreement between the manufacturer and the purchaser. These conditions are listed as follows. 4.2.1 Environmental conditions Ambient temperature exceeding the standard service conditions: refer to IEC 60068-2-14 and IEC 60068-2-78. Exposure to salt spray: refer to IEC 60068-2-52.
46、Abnormal vibrations or shocks: refer to IEC 60068-2-6 and IEC 60068-2-29. Limitation on weight or space, including clearances to nearby conducting objects. 4.2.2 System conditions System voltages, current or frequency operating conditions exceeding the ratings of the MOVs. 5 Basic function and MOV c
47、omponent description The components described in this document are ceramics made of metal oxides (in general zinc oxide with other additives). They behave as a non-linear component with a continuous curve V versus I (limiting component as described in IEC 61643-1). They may be provided or not with e
48、lectrodes, encapsulated or not in resin, and may be fitted with wires or brackets for connection purposes. They may be used alone or in conjunction with other MOV or other components in surge protective devices (SPDs). Page8 EN61643331:200361643-331 IEC:2003 9 6 Identification 6.1 Generalities A ZnO
49、 varistor corresponding to this specification is identified by its functional and constructional characteristics (6.2); the manufacturing inspections to which it is subjected (6.3). These data as a whole constitute the identification file of one type of varistor. 6.2 Functional and constructive characteristics The following functional characteri
