1、BRITISH STANDARD BS EN 60068-2-42: 2003 Environmental testing Part 2-42: Tests Test Kc: Sulphur dioxide test for contacts and connections The European Standard EN 60068-2-42:2003 has the status of a British Standard ICS 31.220.10 BS EN 60068-2-42:2003 This British Standard was published under the au
2、thority of the Standards Policy and Strategy Committee on 24 September 2003 BSI 24 September 2003 ISBN 0 580 42669 6 National foreword This British Standard is the official English language version of EN 60068-2-42:2003. It is identical with IEC 60068-2-42:2003. It supersedes BS 2011-2.1Kc:1991 whic
3、h is withdrawn. The UK participation in its preparation was entrusted by Technical Committee EPL/48, Electromechanical components and mechanical structures for electronic equipment, to Subcommittee EPL/48/2, Connectors, which has the responsibility to: A list of organizations represented on this sub
4、committee can be obtained on request to its secretary. Cross-references The British 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 t
5、he “Search” facility of the BSI Electronic Catalogue or of British Standards Online. 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
6、legal obligations. aid enquirers to understand the text; present to the responsible 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
7、. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 9 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEAN STAND
8、ARD EN 60068-2-42 NORME EUROPENNE EUROPISCHE NORM September 2003 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 2003 CENELEC -
9、All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60068-2-42:2003 E ICS 31.220.10 English version Environmental testing Part 2-42: Tests Test Kc: Sulphur dioxide test for contacts and connections (IEC 60068-2-42:2003) Essais denvironnement Pa
10、rtie 2-42: Essais Essai Kc: Essai lanhydride sulfureux pour contacts et connexions (CEI 60068-2-42:2003) Umweltprfungen Teil 2-42: Prfungen Prfung Kc: Schwefeldioxid fr Kontakte und Verbindungen (IEC 60068-2-42:2003) This European Standard was approved by CENELEC on 2003-09-01. CENELEC members are b
11、ound 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 obtained on application to the
12、 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 Central Secretariat has the sa
13、me status as the official versions. CENELEC members are the national 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, Swi
14、tzerland and United Kingdom. EN 66008-2-242:300 - - 2 Foreword The text of document 48B/1324/FDIS, future edition 3 of IEC 60068-2-42, prepared by SC 48B, Connectors, of IEC TC 48, Electromechanical components and mechanical structures for electronic equipment, was submitted to the IEC-CENELEC paral
15、lel vote and was approved by CENELEC as EN 60068-2-42 on 2003-09-01. 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) 2004-06-01 latest date by which the national standards con
16、flicting with the EN have to be withdrawn (dow) 2006-09-01 Annexes designated “normative“ are part of the body of the standard. Annexes designated “informative“ are given for information only. In this standard, annex ZA is normative and annex A is informative. Annex ZA has been added by CENELEC. _ E
17、ndorsement notice The text of the International Standard IEC 60068-2-42:2003 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliography, the following note has to be added for the standard indicated: IEC 60068-1 NOTE Harmonized as EN 60068-1:19
18、94 (not modified). _ Page2 EN60068242:2003060-86-242 IE:C2003 3 ENVIRONMENTAL TESTING Part 2-42: Tests Test Kc: Sulphur dioxide test for contacts and connections 1 Scope and object This test: is intended to provide accelerated means to assess the corrosive effects of atmospheres polluted with sulphu
19、r dioxide on contacts and connections; is particularly suitable for giving information on a comparative basis; is not suitable as a general corrosion test, i.e. it may not predict the behaviour of contacts and connections in industrial atmospheres. NOTE In view of the limited information to be obtai
20、ned from accelerated corrosion tests, particular attention should be paid to the guidance on this test given in IEC 60068-2-49. Reference should also be made to IEC 60355. The object of this test is: a) to determine the influence of atmospheres containing sulphur dioxide on the contact properties of
21、 precious metal or precious metal-covered contacts and connections, excluding contacts consisting of silver and some of its alloys; b) to check solderless connections with regard to their tightness or effectiveness. In all tests, the major criterion of performance will be the change in contact resis
22、tance caused by exposure to the sulphur dioxide test atmosphere. 2 Normative references The following 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 docume
23、nt (including any amendments) applies. IEC 60512-2-1:2002, Connectors for electronic equipment Tests and measurements Part 2-1: Electrical continuity and contact resistance tests Test 2a: Contact resistance Millivolt level method 3 Test apparatus The test apparatus consists of a climatic system, tes
24、t enclosures, a gas delivery system and means for measuring gas concentration, detailed in Annex A. 3.1 Test chamber The test chamber and its auxiliary parts shall be made of materials that do not react with or absorb sulphur dioxide and which do not influence the corrosive effects of the test atmos
25、phere. The mixture of air and sulphur dioxide shall enter and leave the chamber through tubes with sufficiently large diameters such that the total flow through the chamber is at least three, but not more than five, changes of the atmosphere per hour. The exhaust from the chamber should not be allow
26、ed to enter the laboratory. Page3 EN60068242:2003060-86-242 IE:C2003 4 The detailed construction of the chamber including the method of producing the test atmosphere is optional, provided that: a) the conditions in that part of the chamber occupied by the specimens are within the specified limits; b
27、) the specimens under test are protected from direct exposure to the incoming gas flow; c) arrangements are made to move the specimens through the atmosphere at an average rate of 20 m/h to 60 m/h (approximately 6 mm/s to 17 mm/s) or alternatively to gently stir the atmosphere, obtaining a similar r
28、elative velocity between atmosphere and specimens; d) condensation does not occur inside the test chamber; e) the test chamber is not exposed to direct sunlight and the level of illumination (provided by daylight or by incandescent or fluorescent lamps) measured within the test chamber at the site o
29、f any exposed surface is 50 lx to 300 lx. An example of a suitable test chamber is given in Annex A. 4 Test atmosphere The composition of the atmosphere within the chamber shall satisfy the following conditions: sulphur dioxide: 25 10 6 5 10 6vol/vol (parts per million). This shall be taken as the t
30、otal oxides of sulphur expressed as SO 2 . Small concentrations of sulphur oxides other than SO 2(such as SO 3 ) are permitted to be present to a maximum concentration of 1 % of the total sulphur oxides; temperature: 25 C 2 C; relative humidity: 75 %. The relative humidity shall be held as close as
31、possible to 75 %, but shall in no case exceed 80 % nor fall below 70 %. The test atmosphere may be obtained by mixing directly the necessary constituents in such a way as to ensure a homogeneous mixture (more than one stage may be necessary to obtain a homogeneous distribution of the small quantity
32、of SO 2 ). An example for such a process is given in Annex A. 5 Preconditioning The specimens under test shall not be cleaned in any way unless required by the manufacturers instructions, the relevant detail specification, or agreed upon between the interested parties. Page4 EN60068242:2003060-86-24
33、2 IE:C2003 5 6 Method 6.1 Initial measurements The relevant specification may require that, before and after test, a resistance measurement be carried out in combination with mechanical tests (e.g. shock or vibration tests). The specimens shall be measured, mechanically checked and subjected to mech
34、anical endurance as required by the relevant specification. The contact resistance shall be measured in accordance with IEC 60512-2-1, in order to avoid damage to films formed on contact surfaces. 6.2 Procedure Prior to the commencement of the test it shall be established by suitable measurements th
35、at stable conditions for the concentration of sulphur dioxide, the temperature and the relative humidity have been achieved. Periodic checks shall be made during the test to ensure that these conditions are maintained. Care shall be taken that the specimens are placed in a way that they do not come
36、in contact with each other and that they do not cover or shield each other from the test atmosphere. Adequate precautions shall be taken to ensure that the contacts are not disturbed during the exposure period. Specimens shall be exposed with contacts open and/or closed as required by the relevant d
37、etail specification. The specimens shall be exposed without any electrical load or as required by the detail specification. The specimens shall be continuously exposed to the test atmosphere for 4, 10 or 21 days as required by the detail specification. 6.3 Final measurements The specimens shall be r
38、emoved from the chamber and stored under standard recovery conditions for not less than 1 h and not more than 2 h before contact resistance measurements are made. Adequate precautions shall be taken to ensure that the contacts are not disturbed. The method used for measuring the contact resistance s
39、hould be the same as used for the initial measurement. NOTE If the necessary measurements cannot be made within the specified time, the period of storage under recovery conditions may be extended to a maximum of 24 h; such an extension shall be mentioned in the report. In general, specimens which ar
40、e exposed with contacts in the mated condition shall have their contact resistance measured before they are unmated. Specimens exposed with contacts in the unmated condition shall be mated once and the contact resistance shall then be measured. Page5 EN60068242:2003060-86-242 IE:C2003 6 Treatment of
41、 the contacts before final measurements and the details of measurements shall be made as required by the relevant specification. Visual inspection of the specimens may be required by the detail specification. 7 Details to be specified The relevant specification shall specify the following details: a
42、) measurements, checks and mechanical endurance to be made prior to the test; b) if contacts are mated or unmated during the test; c) electrical loading or operational conditions of the specimens, if applicable; d) duration of the test; e) measurements, checks and visual inspection to be made at the
43、 end of the test. Page6 EN60068242:2003060-86-242 IE:C2003 7 Annex A (informative) Generation of the test atmosphere by direct mixing of sulphur dioxide with air As an example, this Annex schematically describes an apparatus suitable for producing the test atmosphere by directly mixing the necessary
44、 components. Other apparatus and methods of mixing and control may be used, provided they comply with all the requirements of this specification. The test apparatus shown in Figure A.1 is composed of an air-conditioning unit, a gas supply with dosing pump, a test cabinet, a gas washing bottle for cl
45、eaning the exhaust gases of sulphur dioxide, an air flow meter and a suction pump. Corrosive gas injector Fresh air filter Air conditioning plant Dosing pump Gas supply Pressure-reducing valve Baffle plates Heating and/or cooling device Isolation Gas washing bottle Air flowmetre Suction pump and fre
46、ezing trap IEC 1638/03Figure A.1 Schematic drawing of apparatus with generation of conditioning atmosphere Page7 EN60068242:2003 - - 3 EN 66008-2-242:300 Annex ZA (normative) Normative references to international publications with their corresponding European publications This European Standard inco
47、rporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this Eur
48、opean Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD appl
49、ies. Publication Year Title EN/HD Year IEC 60512-2-1 2002 Connectors for electronic equipment - Tests and measurements Part 2-1: Electrical continuity and contact resistance tests - Test 2a: Contact resistance - Millivolt level method EN 60512-2-1 2002 9egaP 3002:24286006NEPage8 EN60068242:2003060-86-242 IE:C2003 8 Bibliography IEC 60068-1:1988, Environmental testi
