1、BRITISH STANDARD BS EN 60931-3:1997 IEC60931-3: 1996 Shunt power capacitors of the non-self-healing type for a.c. systems having a rated voltage up to and including1kV Part 3: Internal fuses The European Standard EN60931-3:1996 has the status of a British Standard ICS 31.060.70BSEN60931-3:1997 This
2、British Standard, having been prepared under the directionof the Electrotechnical Sector Board, was published underthe authority of the Standards Board and comes into effect on 15September1997 BSI 09-1999 ISBN 0 580 27872 7 National foreword This British Standard is the English language version of E
3、N60931-3:1996. It is identical with IEC60931-3:1996. The UK participation in its preparation was entrusted to Technical Committee PEL/33, Power capacitors, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries
4、 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. A list of organizations represented on this committee can be obtained on request to its secretary. From1 January1997, all IEC pu
5、blications have the number60000 added to the old number. For instance, IEC27-1 has been renumbered as IEC60027-1. For a period of time during the change over from one numbering system to the other, publications may contain identifiers from both systems. Cross-references Attention is drawn to the fac
6、t that CEN and CENELEC Standards normally include an annex which lists normative references to international publications with their corresponding European publications. The BritishStandards which implement international or European publications referred to in this document may be found in the BSI S
7、tandards Catalogue under the section entitled “International Standards Correspondence Index, or by using the “Find facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible
8、 for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, theEN title page, pages2 to6 and a back cover. This standard has been updated (se
9、e copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsBSEN60931-3:1997 BSI 09-1999 i Contents Page National foreword Inside front cover Foreword 2 Text of EN60931-
10、3 3ii blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN60931-3 October1996 ICS 31.060.70 Descriptors: Electric equipment, powercapacitors, instrument shunts, alternating current, protection, electrical insulation, cutouts, specifications, tests, performance test English version Shunt power c
11、apacitors of the non-self-healing type for a.c. systems having a rated voltage up to and including1kV Part3: Internal fuses (IEC931-3:1996) Condensateurs shunt de puissance non autorgnrateurs pour rseaux courant alternatif de tension assigne infrieure ou gale 1kV Partie3: Fusibles internes (CEI931-3
12、:1996) Nichtselbstheilende Leistungs-Parallelkondensatoren fr Wechselstromanlagen mit einer Nennspannung bis1kV Teil3: Eingebaute Sicherungen (IEC931-3:1996) This European Standard was approved by CENELEC on1996-07-02. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations whi
13、ch 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
14、 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
15、national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and UnitedKingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Norm
16、alisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1996 Copyright reserved to CENELEC members Ref. No. EN60931-3:1996 EEN60931-3:1996 BSI 09-1999 2 Foreword The text of document33/233/FDIS, future edition1 of IEC931-3,
17、 prepared by IEC TC33, Power capacitors, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN60931-3 on1996-07-02. The following dates were fixed: For products which have complied with the relevant national standard before1997-05-01, as shown by the manufacturer or by a c
18、ertification body, this previous standard may continue to apply for production until2002-05-01. Annexes designated “normative are part of the body of the standard. Annexes designated “informative are given for information only. In this standard, Annex A and Annex ZA are normative and Annex B is info
19、rmative. Annex ZA has been added by CENELEC. Endorsement notice The text of the International Standard IEC931-3:1996 was approved by CENELEC as a European Standard without any modification. Contents Page Foreword 2 1 Scope and object 3 2 Normative reference 3 3 Definitions 3 4 Performance requiremen
20、ts 3 4.1 General 3 4.2 Disconnecting requirements 3 4.3 Withstand requirements 3 5 Tests 3 5.1 Routine tests 3 5.2 Type tests 4 5.3 Disconnecting test on fuses 4 Annex A (normative) Test procedures for the disconnecting test on internal fuses 5 Annex B (informative) Guide for coordination of fuse pr
21、otection 6 Annex ZA (normative) Normative references to international publications with their corresponding European publications 6 latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 1997-05-01 latest date by w
22、hich the national standards conflicting with the EN have to be withdrawn (dow) 1997-05-01EN60931-3:1996 BSI 09-1999 3 1 Scope and object This part of IEC931 applies to internal fuses which are designed to isolate faulty capacitor elements or a capacitor unit, in order to allow operation of the remai
23、ning parts of that capacitor unit and the bank in which the capacitor unit is connected. Such fuses are not a substitute for a switching device such as a circuit-breaker, or for external protection of the capacitor bank or any part thereof. The object of this part of IEC931 is to formulate requireme
24、nts regarding performance and testing and to provide a guide for co-ordination of fuse protection. 2 Normative reference The following normative document contains provisions which, through reference in this text, constitute provisions of this part of IEC931. At the time of publication, the edition i
25、ndicated was valid. All normative documents are subject to revision, and parties to agreements based on this part of IEC931 are encouraged to investigate the possibility of applying the most recent edition of the normative document indicated below. Members of IEC and ISO maintain registers of curren
26、tly valid International Standards. IEC931-1:1989, Shunt power capacitors of the non-self-healing type for a.c. systems having a rated voltage up to and including1000V Part1:General Performance, testing and rating Safety requirements Guide for installation and operation Amendment1(1991). 3 Definition
27、s For the purpose of this part of IEC931, the definitions of IEC931-1 apply. 4 Performance requirements 4.1 General The fuse is connected in series to the element(s) which the fuse is intended to isolate if the element(s) becomes faulty. The range of currents and voltages for the fuse is therefore d
28、ependent on the capacitor design, and in some cases also on the bank in which the fuse is connected. The requirements are valid for a bank or a capacitor switched by restrike-free circuit-breakers. If the circuit-breakers are not restrike-free, other requirements shall be agreed between manufacturer
29、 and purchaser. The operation of an internal fuse is in general determined by one or both of the two following factors: the discharge energy from elements or units connected in parallel with the faulty element or unit; the power-frequency fault current. 4.2 Disconnecting requirements The fuse shall
30、enable the faulty element to be disconnected when electrical breakdown of elements occurs in a voltage range, in which u 1 =0,9 U Nis the lowest, and u 2 =1,5 U Nis the highest (instantaneous) value of the voltage between the terminals of the unit at the instant of fault. The u 1and u 2values are ba
31、sed on the voltage that may normally occur across the capacitor unit terminals at the instant of electrical breakdown of the element. The u 2value is of a transient nature and allowance has been made for damping. If the purchaser specifies u 1and u 2values other than those indicated, for example for
32、 filter capacitors, the lower and upper test voltage limits shall be changed according to an agreement between manufacturer and purchaser. 4.3 Withstand requirements 4.3.1 After operation, the fuse assembly shall withstand full element voltage or full voltage between the terminals of the disconnecte
33、d capacitor, plus any unbalance voltage due to fuse action, and any short-time transient overvoltages normally experienced during the life of the capacitor. 4.3.2 Throughout the life of the capacitor, the fuses shall be capable of carrying continuously a current equal to or greater than the maximum
34、permissible unit current divided by the number of parallel fuses. 4.3.3 The fuses shall be capable of withstanding the inrush-currents due to the switching operations expected during the life of the capacitor. 4.3.4 The fuses connected to the undamaged elements shall be able to carry the discharge c
35、urrents due to the breakdown of elements. 4.3.5 The fuses shall be able to carry the currents due to short-circuit faults on the bank external to the unit(s) occurring within the voltage range in accordance with4.2. 5 Tests 5.1 Routine tests The fuses shall be able to withstand all routine tests of
36、the capacitor unit in accordance with IEC931-1. 2 2EN60931-3:1996 4 BSI 09-1999 5.2 Type tests 5.2.1 The fuses shall be able to withstand all type tests of the capacitor units in accordance with IEC931-1 and IEC931-2. The unit(s) shall have passed all routine tests stated in IEC931-1. 5.2.2 The disc
37、onnecting test on fuses (see5.3) shall be performed either on one complete capacitor unit or, at the choice of the manufacturer, on two units, one unit being tested at the lower voltage limit, and one unit at the upper voltage limit, in accordance with5.3.1. NOTEDue to testing, measuring and safety
38、circumstances, it may be necessary to make some modifications to the unit(s) under test; for example those indicated in Annex A. Seealso the different test methods given in Annex A. 5.2.3 Type tests are considered valid if they are performed on capacitor(s) of a design identical with that of the cap
39、acitor offered, or on a capacitor(s) of a design that does not differ from it in any way that might affect the properties to be checked by the type tests. 5.3 Disconnecting test on fuses 5.3.1 Test procedure The disconnecting test on fuses shall be performed at the lower voltage limit of0,9 U Nand a
40、t the upper voltage limit of1,6 U N . If the test is carried out with d.c., the test voltage shall be times the corresponding a.c. test voltage. If the test is carried out with a.c., the triggering of the element failure with a voltage peak shall not be necessary for the test at the lower voltage li
41、mit. Certain test methods are indicated in Annex A. 5.3.2 Capacitance measurement After the test, the capacitance shall be measured to prove that the fuses have blown. A measuring method shall be used that is sufficiently sensitive to detect the capacitance change caused by one blown fuse. 5.3.3 Ins
42、pection of the unit Before opening, no significant deformation of the container shall be apparent. After opening the container, a check shall be made to ensure that: a) no significant deformation of sound fuses is apparent; b) no more than one additional fuse (or one-tenth of fused elements directly
43、 in parallel) has been damaged (seenote1 of clauseA.1). If method b) given in Annex A is used, note1 of clauseA.1 shall be observed. NOTE 1A small amount of blackening of the impregnant will not affect the quality of the capacitor. NOTE 2Dangerous trapped charges may be present on elements disconnec
44、ted either by operated fuses or by damage to their connections. All elements should be discharged with great care. 5.3.4 Voltage test after opening the container A voltage test shall be carried out by applying a d.c. voltage of2,6 U Ne(U Neelement voltage) for10s across the broken-down element and t
45、he gap in its blown fuse. During the test, the gap shall be in the impregnant. No breakdown over the fuse gap is allowed. NOTEFor units with all elements in parallel and for all units if test procedure b), c), d), or e) indicated in Annex A is used, this test can be replaced by an a.c. test before t
46、he opening of the unit. The test voltage between the terminals is calculated using the capacitance ratio such that the voltage across the breakdown element and the gap in its blown fuse is2,6 U Ne /. 2 2EN60931-3:1996 BSI 09-1999 5 Annex A (normative) Test procedures for the disconnecting test on in
47、ternal fuses A.1 General One of the test procedures a), b), c), d), e) or an alternative method, shall be used. The capacitor voltage and current shall be recorded during the test to verify that the fuse has disconnected correctly. For d.c. testing, the test voltage shall be maintained at least30s a
48、fter breakdown to ensure that the disconnection of the fuse is unaided by disconnection of the power supply. To verify the current-limiting behaviour of the fuses when tested at the upper voltage limit, the voltage drop, excluding transient, across the blown fuse shall not exceed30%. If the voltage
49、drop exceeds30%, precaution shall be taken to make certain that the parallel stored energy and the power-frequency fault current available from the test system are representative of service conditions. A test shall then be made under these conditions to demonstrate satisfactory operation of the fuse. NOTE 1At the upper voltage limit, one additional fuse (or one-tenth of the fused elements directly in parallel) connected to a sound element(s) is allowed to be damaged. NOTE 2Precautions should be taken when performing this test again
