1、BRITISH STANDARD BS EN 60068-2-52: 1996 IEC 68-2-52: 1996 Environmental testing Part 2: Tests Test Kb. Salt mist cyclic (sodiumchloride solution) The European Standard EN60068-2-52:1996 has the status of a British Standard This Part should be read in conjunction with BSEN60068-1:1995 General and gui
2、dance ICS 19.040BSEN 60068-2-52:1996 This British Standard, having been prepared under the direction of the Electrotechnical Sector Board, was published underthe authority of the Standards Board and comes intoeffect on 15 October 1996 BSI 10-1998 The following BSI references relate to the work on th
3、is standard: Committee reference GEL/50 Draft for comment 93/207795 DC ISBN 0 580 26156 5 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee GEL/50, Environmental testing of electrotechnical products, upon which the followin
4、g bodies were represented: Federation of the Electronics Industry GAMBICA (BEAMA Ltd.) Ministry of Defence Society of Motor Manufacturers and Traders Limited The following bodies were also represented in the drafting of the standard, through subcommittees and panels: Biodeterioration Society Institu
5、te of Materials National Supervising Inspectorate (BSI PC) Society of Environmental Engineers Amendments issued since publication Amd. No. Date CommentsBSEN 60068-2-52:1996 BSI 10-1998 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 Text of EN 60068-2-52 3 L
6、ist of references Inside back coverBSEN 60068-2-52:1996 ii BSI 10-1998 National foreword This British Standard has been prepared by Technical Committee GEL/50 and is the English language version of EN60068-2-52:1996 Environmental testing Part 2: Tests Test Kb: Salt mist, cyclic (sodium chloride solu
7、tion), published by the European Committee for Electrotechnical Standardization (CENELEC). It is identical with IEC68-2-52:1996 published by the International Electrotechnical Commission (IEC). It supersedes BS2011-2.1Kb:1987 which is withdrawn. A British Standard does not purport to include all the
8、 necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-references Publication referred to Corresponding British Standard BS EN 60068 Environment
9、al testing IEC 68-1:1988 BS EN 60068-1:1995 General and guidance BS 2011 Environmental testing Part 2.1 Tests IEC 68-2-3:1969 Part 2.1Ca:1977 Test Ca. Damp heat, steady state Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, the EN title page, pages 2 to
10、8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on theinside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 60068-2-52 March 1996 ICS 19.040 Superse
11、des HD 323.2.52 S1:1987 Incorporates corrigendum July 1996 Descriptors: Components, equipments, environmental tests, corrosion test, cyclic test, salt mist, sodium chloride solution, test procedures, drafting component standards, drafting equipment standards English version Environmental testing Par
12、t 2: Tests Test Kb: Salt mist, cyclic (sodiumchloridesolution) (IEC 68-2-52:1996) Essais denvironnement Partie2: Essais Essai Kb: Brouillard salin, essai cyclique (solution de chlorure de sodium) (CEI68-2-52:1996) Umweltprfungen Teil2: Prfverfahren Prfung Kb: Salznebel, zyklisch (Natriumchloridlsung
13、) (IEC68-2-52:1996) This European Standard was approved by CENELEC on 1996-03-05. 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
14、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 translation under the resp
15、onsibility 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, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg,
16、 Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. 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 199
17、6 Copyright reserved to CENELEC members Ref. No. EN60068-2-52:1996EEN60068-2-52:1996 BSI 10-1998 2 Foreword The text of document 50B/363/FDIS, future edition2 of IEC68-2-52, prepared by SC50B, Climatic tests, of IECTC50, Environmental testing, was submitted to the IEC-CENELEC parallel vote and was a
18、pproved by CENELEC as EN60068-2-52 on 1996-03-05. This European Standard supersedes HD323.2.52S1:1987. The following dates were fixed: Annexes designated “normative” are part of the body of the standard. In this standard, annex ZA is normative. Annex ZA has been added by CENELEC. Contents Page Forew
19、ord 2 1 Scope 3 2 Normative references 3 3 General description of the test 3 4 Test apparatus 4 5 Salt solution 4 6 Severities 4 7 Initial measurements 5 8 Pre-conditioning 5 9 Testing 5 10 Recovery (at the end of testing) 6 11 Final measurements 6 12 Information to be given in the relevant specific
20、ation 6 Annex ZA (normative) Normative references tointernational publications with their corresponding European publications 8 Figure 1 Schematic time-scale of the differenttest severities (1) to (6) 7 latest date by which the EN has to be implemented at national level by publication of an identica
21、l national standard or by endorsement (dop) 1996-12-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 1996-12-01EN60068-2-52:1996 BSI 10-1998 3 1 Scope This test is intended for application to components or equipment designed to withstand a salt-laden
22、atmosphere, depending on the chosen severity. Salt can degrade the performance of parts manufactured using metallic and/or non-metallic materials. The mechanism of salt corrosion on metallic materials is electrochemical, whereas the degradation effects experienced on non-metallic materials are cause
23、d by complex chemical reactions of the salts with the materials involved. The rate at which corrosive action takes place is dependent, to a large extent, on the supply of oxygenated salt solution to the surface of the test specimen, the temperature of the specimen and the temperature and humidity of
24、 the environment. Apart from the corrosive effects, this test may be used to indicate deterioration of some non-metallic materials by assimilation of salts. In the following test methods, the period of spraying with the relevant salt solution is sufficient to wet the specimen thoroughly. Because thi
25、s wetting is repeated after intervals of storage under humid conditions (severities (1) and (2) and in some cases (severities (3) to (6) supplemented by storage under a standard atmosphere for testing, it goes some way to reproducing the effects of natural environments. Severities (1) and (2) are in
26、tended to be used for testing products which are used in a marine environment, or in close proximity to the sea. Severity (1) should be used to test products which are exposed to the environment for much of their operational life (e.g. ship radar, deck equipment). Severity (2) should be used to test
27、 products which may be exposed to the marine environment from time to time but will normally be protected by an enclosure (e.g. navigational equipment which will normally be used on the bridge or in a control room). Additionally, severities (1) and (2) are commonly used as a general corrosion test i
28、n component quality assurance procedures. Severities (3) to (6) are intended for products where, under normal use, there is a frequent change between salt-laden and dry atmosphere, e.g. automobiles and their parts. Severities (3) to (6), compared to severities (1) and (2), therefore include an addit
29、ional storage under a standard atmosphere for testing. The period of dry atmosphere may happen, in practice, during breaks of operation, e.g. during the weekend. This inclusion of such a dry period in severities (3) to (6) leads to corrosion mechanism which can be quite different from those under co
30、nstant humid conditions. The test is accelerated compared with most service conditions. However, it is not possible to establish an overall acceleration factor for all kinds of specimen (seeIEC355). 2 Normative references The following normative documents contain provisions which, through reference
31、in this text, constitute provisions of this part of IEC68-2. At the time of publication, the editions indicated were valid. All normative documents are subject to revision, and parties to agreements based on this part of IEC68-2 are encouraged to investigate the possibility of applying the most rece
32、nt editions of the normative documents indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. IEC68-1:1988, Environmental testing Part1: General and guidance. IEC 68-2-3:1969, Environmental testing Part2: Tests Test Ca: Damp heat, steady state. IEC 355
33、:1971, An appraisal of the problems of accelerated testing for atmospheric corrosion. 3 General description of the test For severities (1) and (2), the test procedure is separated into a specified number of periods of spraying by a salt mist at a temperature between 15 C and 35 C, each followed by a
34、 storage period under humid conditions at 40C 2C, % relative humidity. For severities (3), (4), (5) and (6) the test procedure is separated into a specified number of test cycles. Each test cycle consists of four periods of spraying by a salt mist at a temperature between 15C and35 C, each followed
35、by a storage period under humid conditions at 40C 2 C, % relative humidity, and of one storage period under a standard atmosphere for testing at 23C 2 C and 45% to 55% relative humidity after these four periods of spraying and storage under humid conditions. If the spray period and storage period ar
36、e carried out in different chambers, care should be taken to avoid loss of salt solution deposits on the specimen and to avoid any damage to the specimen due to handling. The specimen is never energized during the spray period, and not normally during the storage period. 93 3 2 + () 93 3 2 + ()EN600
37、68-2-52:1996 4 BSI 10-1998 4 Test apparatus 4.1 Salt mist chamber The chamber for this test shall be constructed of such materials that will not influence the corrosive effects of the salt mist. The detailed construction of the chamber, including the method of producing the salt mist is optional, pr
38、ovided that: a) the conditions in the chamber are within the limits specified; b) a sufficiently large volume with constant, homogeneous conditions (not affected by turbulence) is available; these conditions should not be influenced by the specimen under test; c) no direct spray impinges upon the sp
39、ecimen under test; d) drops of liquid accumulating on the ceiling, the walls, or other parts cannot drip on the specimen; e) the chamber shall be properly vented to prevent pressure build-up and allow uniform distribution of the salt mist. The discharge end of the vent shall be protected from strong
40、 draughts which can cause strong air currents in the chamber. 4.1.1 Atomizer(s) The atomizer(s) shall be of such a design and construction as to produce a finely divided, wet, dense mist. The atomizer(s) shall be made of material that is non-reactive to the salt solution. 4.1.2 The sprayed solution
41、shall not be re-used. 4.1.3 Air supply If use is made of compressed air, that air shall, when entering the atomizer(s), be essentially free from all impurities, such as oil and dust. Means shall be provided to humidify the compressed air as required to meet the operating conditions. The air pressure
42、 shall be suitable to produce a finely divided dense mist with the atomizer(s) used. To ensure against clogging of the atomizer(s) by salt deposition, the air is recommended to have a relative humidity of at least 85% at the point of release from the nozzle. A satisfactory method is to pass the air
43、in very fine bubbles through a tower containing water, which should be automatically maintained at a constant level. The temperature of this water shall be not less than that of the chamber. The air pressure shall be capable of adjustment so that the collection rate as specified in 9.2 can be mainta
44、ined. 4.2 Humidity chamber The chamber shall conform to the requirements of IEC68-2-3, i.e. it shall maintain a humidity of% at a temperature of 40C 2 C. 4.3 Chamber for standard atmosphere The chamber shall conform to the requirements of 5.2 of IEC68-1, (table second line, wide range), i.e. it shal
45、l maintain a humidity of 45% to 55% at a temperature of 23C 2 C. 5 Salt solution 5.1 5% sodium chloride (NaCl) solution 5.1.1 The salt used for the test shall be high-quality sodium chloride (NaCl) containing, when dry, not more than 0,1% sodium iodide and not more than 0,3% of total impurities. The
46、 salt solution concentration shall be 5% 1% by weight. The solution shall be prepared by dissolving 5 1 parts by weight of salt in 95 parts by weight of distilled or demineralized water. NOTEThe relevant specification may call for other salt solutions, the composition and characteristics (density, p
47、H value, etc.) of which should be stated clearly in the specification, e.g. to simulate the special effects of a marine environment. 5.1.2 The pH value of the solution shall be between6,5 and 7,2 at a temperature of20C 2 C. The pH value shall be maintained within this range during conditioning; for
48、this purpose, diluted hydrochloric acid or sodium hydroxide may be used to adjust the pH value, provided that the concentration of NaCl remains within the prescribed limits. The pH value shall be measured when preparing each new batch of solution. 6 Severities 6.1 The severity of the test is defined
49、 as follows. For severities (1) and (2): by the combination of the number of spray periods and the duration of the storage under humid conditions following each spray period. For severities (3) to (6): by the number of test cycles consisting of four spraying periods with storage under humid conditions after each one, and one additional storage period under a standard atmosphere for testing after these four periods of spraying and storage under humid conditions. 93 3 2 + ()EN60068-2-52:1996 BSI 10-1998 5 6.
