BS EN 60343-1993 Recommended test methods for determining the relative resistance of insulating materials to breakdown by surface discharges《测定绝缘材料耐表面放电击穿的相对电阻的推荐试验方法》.pdf

1、BRITISH STANDARD BSEN 60343:1993 IEC343:1991 Recommended test methods for determining the relative resistance of insulating materials to breakdown by surface discharges The European Standard EN60343:1992 has the status of a BritishStandard UDC 621.315.61:620.1:621.3.015.532BSEN60343:1993 This Britis

2、hStandard, having been prepared under the directionof the Cables and Insulation Standards Policy Committee, was published underthe authority of the Standards Board and comes intoeffect on 15 June 1993 BSI 12-1999 The following BSI references relate to the work on this standard: Committee reference C

3、IL/15 Special announcement in BSINews April 1993 ISBN 0 580 21839 2 Cooperating organizations The European Committee for Electrotechnical Standardization (CENELEC), under whose supervision this European Standard was prepared, comprises the national committees of the following countries: Austria Ital

4、y Belgium Luxembourg Denmark Netherlands Finland Norway France Portugal Germany Spain Greece Sweden Iceland Switzerland Ireland United Kingdom Amendments issued since publication Amd. No. Date CommentsBSEN60343:1993 BSI 12-1999 i Contents Page Cooperating organizations Inside front cover National fo

5、reword ii Foreword 2 Text of EN60343 3 National annex NA (informative) Committees responsible Inside back cover National annex NB (informative) Cross-references Inside back coverBSEN60343:1993 ii BSI 12-1999 National foreword This BritishStandard has been prepared under the direction of the Cables a

6、nd Insulation Standards Policy Committee and is the English language version of EN60343:1992 Recommended test methods for determining the relative resistance of insulating materials to breakdown by surface discharges, published by the European Committee for Electrotechnical Standardization (CENELEC)

7、. It is identical with IEC343:1991 published by the International Electrotechnical Commission (IEC). A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard

8、 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 to10, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendmen

9、ts incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN60343 October 1992 UDC 621.315.61:620.1:621.3.015:532 Descriptors: Electrical insulating material, solid electrical insulating material, electric strength, ele

10、ctrical endurance test, electrical discharge, electrical breakdown, test condition English version Recommended test methods for determining the relative resistance of insulating materials to breakdownbysurfacedischarges (IEC343:1991) Mthodes dessai recommandes pour la dtermination de la rsistance re

11、lative des matriaux isolants au claquage par les dcharges superficielles (CEI343:1991) Empfohlene Prfverfahren zur Bestimmung der relativen Bestndigkeit isolierender Werkstoffe gegen Durchschlag infolge Oberflchenglimmentladung (IEC343:1991) This European Standard was approved by CENELEC on 1992-09-

12、15. 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 obtai

13、ned 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 Centr

14、al Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.

15、 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1992 Copyright reserved to CENELEC members Ref. No. EN60343:1992 EEN60343:1992 BS

16、I 12-1999 2 Foreword The CENELEC questionnaire procedure, performed for finding out whether or not the International Standard IEC343:1991 could be accepted without textual changes, has shown that no common modifications were necessary for the acceptance as European Standard. The reference document w

17、as submitted to the CENELEC members for formal vote and was approved by CENELEC as EN60343 on15September 1992. The following dates were fixed: Annexes designated “normative” are part of the body of the standard. In this standard, Annex ZA is normative. Contents Page Foreword 2 1 Scope 3 2 Normative

18、references 3 3 Object and principle of test 3 4 Test arrangement 3 5 Electrical apparatus 5 6 Procedure 5 7 Factors to be taken into consideration 5 8 Test report 6 Annex ZA (normative) Other international publications quoted in this standard with thereferences of the relevant European publications

19、10 Figure 1 Examples of general arrangementofelectrodes 7 Figure 2 Example of general arrangementofelectrodes 8 Figure 3a Life line in semilog plot 9 Figure 3b Life line in log-log plot 9 latest date of publication of an identical national standard (dop) 1993-06-01 latest date of withdrawal of confl

20、icting national standards (dow) 1993-06-01EN60343:1992 BSI 12-1999 3 1 Scope This International Standard concerns endurance tests with surface discharges. It is intended to assess the relative resistance of solid insulating materials to breakdown when exposed to surface discharges. 2 Normative refer

21、ences The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International St

22、andard are encouraged to investigate the possibility of applying the most recent editions of the standards listed below. Members of IEC and ISO maintain registers of currently valid International Standards. IEC60, High-voltage test techniques. IEC212:1971, Standard conditions for use prior to and du

23、ring the testing of solid electrical insulating materials. IEC270:1981, Partial discharge measurements. 3 Object and principle of test Simple means are required for assessing the relative resistance of solid insulating materials to breakdown when exposed to surface discharges while stressed by elect

24、rical field strengths at frequencies used in industrial service. Experience shows that endurance tests, taking as a criterion the complete puncture of the material in the presence of surface discharges from several types of electrodes, provide a similar and reproducible classification of materials w

25、ith respect to this type of stressing, provided that dry air is circulated around the electrodes and over the surface of the specimen during the test. 4 Test arrangement 4.1 Test electrodes The tests shall be made using a stainless steel cylindrical electrode and a plate electrode. The precise grade

26、 of stainless steel is not important. These electrodes shall be as follows: 4.1.1 Cylindrical electrode A cylinder of6mm 0,3mm diameter with the sharp edge removed to leave a1mm radius. This electrode with a mass not exceeding30g shall be normal to the surface of the specimen and rest upon it. With

27、soft materials, a gap not exceeding1004m between this electrode and the specimen is permitted to avoid possible mechanical damage. It is convenient to introduce very thin specimens (thickness less than1004m) between electrodes fixed1004m apart. When necessary to reduce specimen capacitance and minim

28、ize thermal heating, cylindrical electrodes of less than6mm are permissible provided the radius of the electrode edge is maintained at1mm. Figure 1 shows examples of two electrode arrangements which may be used. The arrangement shown in Figure 1b avoids the electrode being seated slightly canted on

29、the specimen when a gap between electrode and specimen is not necessary. Other arrangements are possible. 4.1.2 Plate electrode A plate having an area greater than the area covered by discharges from the cylindrical electrode at the test voltage (see4.2). 4.1.3 Electrode arrangement The electrode ar

30、rangement, whenever possible, should have axial symmetry. The air inlet shall be in a position to obtain an air distribution as uniform as possible on the different electrodes to ensure reproducible results. The test may be made with one or several electrodes above the test sample. If several electr

31、odes are used, the inter-electrode separation shall be sufficient to avoid interaction between the discharges from adjacent electrodes and not less than50mm (see Figure 2). 4.2 Test specimen Whenever possible, tests should be made on specimens of one or more of the following nominal thicknesses:3,0m

32、m,1,6mm,1,0mm,5004m, 1004m and254m. For each nominal thickness, not less than nine specimens (sample areas exposed to discharges) shall be tested at each voltage. The specimen shall be of adequate area to avoid flashover and of uniform thickness, in accordance with normal industry tolerances. The up

33、per surface of the specimen exposed to discharges shall be free from contamination. To prevent small discharges between the specimen and the plate electrode it may be necessary to apply a conducting electrode to the lower surface of the specimen. Care shall be taken when selecting an electrode mater

34、ial to ensure that it does not react with or significantly change the specimen properties. The following materials are in common usage: a) vacuum deposited aluminium, silver or gold. It may be necessary to condition the specimen after the electrode has been applied;EN60343:1992 4 BSI 12-1999 b) tin

35、or aluminium foil,0,025mm thick and of the same size as the test specimen. The foil may be stuck to the specimen with a suitable petroleum or silicone grease. The amount of grease for this purpose should be a minimum. One must also avoid getting grease on the opposite side of the specimen. The greas

36、e shall have no harmful effect on the specimen due to chemical deterioration; c) conducting silver paint. Tests shall be carried out on test specimens which have been conditioned so that they are substantially in equilibrium in accordance with IEC212. NOTESpecial tests may be made on stacks of thin

37、film material, but the results are likely to be very different from tests with a single layer of the same material of equal thickness. 4.3 Test conditions The test is normally carried out on specimens without applied strain but specimens may be subjected to mechanical strain during exposure to disch

38、arges, either by applying tension or by bending sheet specimens over a curved plate electrode. Where mechanical strain is applied,0,5% deformation shall be used for rigid materials and5% for flexible materials. Tests shall normally be made in air dried to a relative humidity not exceeding20% (relati

39、ve humidity of20% or less can be obtained by passing the air through a drying column containing a suitable desiccant such as CaCl 2 ). The degree of dryness of the air and its rate of flow across the upper surface of the specimens shall be sufficient to ensure that under the test conditions the meas

40、ured life is not influenced by local concentrations of degradation products (a flow rate of0,5l/min per specimen has frequently been found satisfactory). NOTE 1Tests are normally made at a temperature of23 C 2 C. It may be advantageous to carry out the tests at temperatures other than23 C 2 C, for e

41、xample at the servicetemperature of the material to be tested, or in accordance with IEC212. NOTE 2In particular cases, tests may be carried out in a medium other than air. NOTE 3To avoid possible health hazard due to the production of active gases (e.g.O 3and NO 2in air), it is advisable to make th

42、e tests in sealed containers, with the air passed across the test specimens and then expelled outside the laboratory. 4.4 Test voltage 4.4.1 Frequency and wave form of the testing voltage It is recommended that tests are made at power frequency(48Hz to62Hz). If tests are to be made at a higher frequ

43、ency, then the functional dependence of the endurance of the test material upon frequency under the conditions of test should be determined so that the equivalent endurance at power frequency may be calculated. It is required to report the calculated life at power frequency and also the test life me

44、asured at the test frequency if other than power frequency. The power or higher-frequency voltage shall be approximately sinusoidal with a ratio of peak value to r.m.s. value within limits of 5%. The test voltage shall not contain harmonics exceeding5% in amplitude (see IEC60). 4.4.2 Test on new mat

45、erials The variation of test life with applied voltage shall be determined for at least three voltages of the same frequency, other conditions being identical. The highest test voltage shall be chosen to give a specimen test life of not less than the equivalent of100h at power frequency. The lowest

46、test voltage shall be chosen to give a specimen test life of not less than the equivalent of5000h at power frequency. In the case of thin materials (thickness less than1004m), it may be permissible to choose the lowest test voltage to give a test life equivalent to1000h at power frequency. Using nin

47、e specimens simultaneously the test can be finished after the fifth breakdown, which represents the central value. 4.4.3 Routine acceptance tests on materials which have previously been assessed The test life at frequency f shall be determined at a voltage which is expected, from previous investigat

48、ions on the material, to cause failure in the equivalent of one year at power frequency. In the case of thin materials (thickness less than1004m), the test voltage shall be chosen to give an expected test life of1000h at power frequency. 2EN60343:1992 BSI 12-1999 5 5 Electrical apparatus 5.1 High-vo

49、ltage source Test at power frequency(48Hz to62Hz) shall be made using a high-voltage transformer, voltage regulator, circuit-breaker and voltmeter in accordance with the recommendations of IEC60. Tests at higher frequencies may be made using either a motor generator and high-voltage transformer or an electronic generator with adequate power output. 5.2 End point control device Endurance is little affected by short interruptions (minutes) of test voltage provided dry air is circulated over the test specimens. Thus it is permissible for a f