1、BRITISH STANDARD BS EN 60068-2-67: 1996 IEC 68-2-67: 1995 Environmental testing Part 2: Tests Test Cy: Damp heat, steady state, accelerated test primarily intended for components The European Standard EN 60068-2-67:1996 has the status of a British Standard This part should be read in conjunction wit
2、h BS EN 60068-1:1995 General andguidance ICS 19.040BSEN 60068-2-67:1996 This British Standard, having been prepared under the directionof the Electrotechnical Sector Board, was published underthe authority of the Standards Board and comes intoeffect on 15 June 1996 BSI 07-1999 The following BSI refe
3、rences relate to the work on this standard: Committee reference GEL/50 Draft for comment 95/207228 DC ISBN 0 580 25661 8 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee GEL/50, Environmental testing of electrotechnical pr
4、oducts, upon which the following bodies were represented: Federation of the Electronics Industry GAMBICA (BEAMA Ltd.) Society of Motor Manufacturers and Traders Limited Ministry of Defence The following bodies were also represented in the drafting of the standard, through subcommittees and panels: I
5、nstitute of Materials National Supervising Inspectorate (BSI PC) Society of Environmental Engineers Biodeterioration Society Amendments issued since publication Amd. No. Date CommentsBS EN 60068-2-67:1996 BSI 07-1999 i Contents Page Committees responsible Inside front cover National foreword ii Fore
6、word 2 Text of EN 60068-2-67 3BSEN 60068-2-67:1996 ii BSI 07-1999 National foreword This British Standard has been prepared by Technical Committee GEL/50 and is the English language version of EN 60068-2-67:1996 Environmental testing Part2: Tests Test Cy: Damp heat, steady state, accelerated test pr
7、imarily intended for components, published by the European Committee for Electrotechnical Standardization (CENELEC). It is identical with IEC 68-2-67:1995 published by the International Electrotechnical Commission(IEC). A British Standard does not purport to include all the necessary provisions of a
8、 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. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN title page, pages 2
9、to 6 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 the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 60068-2-67 January 1996 ICS 19.040 Descriptors: Electricit
10、y, component, electrotechnical product, environment testing, damp heat steady state, accelerated test English version Environmental testing Part 2: Tests Test Cy: Damp heat, steady state, accelerated test primarily intended for components (IEC 68-2-67:1995) Essais denvironnement Partie 2: Essais Ess
11、ai Cy: Essai continu de chaleur humide, essai acclr applicable en premier lieu aux composants (CEI 68-2-67:1995) Umweltprfungen Teil 2: Prfungen Prfung Cy: Feuchte Wrme, konstant, beschleunigte Prfung, vorzugsweise fr Bauelemente (IEC 68-2-67:1995) This European Standard was approved by CENELEC on 1
12、995-11-28. 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 b
13、e 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 responsibility of a CENELEC member into its own language and notified to th
14、e 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, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United K
15、ingdom. 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 1996 Copyright reserved to CENELEC members Ref. No. EN 60068-2-67:1996 EEN
16、60068-2-67:1996 BSI 07-1999 2 Foreword The text of document 50B/360/DIS, future edition 1 of IEC 68-2-67, prepared by SC 50B, Climatic tests, of IEC TC 50, Environmental testing, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60068-2-67 on1995-11-28. The following d
17、ates were fixed: Contents Page Foreword 2 1 Scope 3 2 General description 3 3 Description of test apparatus 3 4 Severities 3 5 Pre-conditioning 4 6 Initial measurements 4 7 Testing 4 8 Intermediate measurements 4 9 Recovery 5 10 Final measurements 5 11 Information to be given in the relevantspecific
18、ation 5 Annex A (informative) Physical significance of the test 6 Annex B (informative) Test apparatus and handling 6 Table 1 Severities 4 latest date by which the ENhas to be implemented at national level by publication of an identical national standard or by endorsement (dop) 1996-09-01 latest dat
19、e by which the national standards conflicting with the EN haveto be withdrawn (dow) 1996-09-01EN60068-2-67:1996 BSI 07-1999 3 1 Scope This International Standard provides a standard test procedure for the purpose of evaluating, in an accelerated manner, the resistance of small electrotechnical produ
20、cts, primarily non-hermetically sealed components, to the deteriorative effect of damp heat. The test is not intended to evaluate external effects such as corrosion and deformation. 2 General description In this test the specimen is subjected to very high levels of unsaturated damp heat for a relati
21、vely long period. Electrical bias is usually applied. The test provides a number of preferred durations at a relative humidity of 85 % and a temperature of85 C. In the case of plastic encapsulated components degradation results from absorption of water-vapour by the plastic and penetration of moistu
22、re along terminals. 3 Description of test apparatus 3.1 The test chamber The chamber shall be so constructed that: a) it can produce the temperature and relative humidity given in Table 1 for a minimum period of 2 000 h without interruption; b) it is capable of providing controlled conditions of tem
23、perature and relative humidity during testing, and the ramp-up to and ramp-down from specified test conditions; c) the temperature and humidity of the chamber can be monitored by means of sensing devices located in the working space and/or other areas giving the same results; d) any water shall be c
24、ontinuously drained from the working space and not re-used; e) condensed water is not allowed to fall on the specimen; f) the materials used in the construction shall not cause any significant corrosion of the specimen, or degradation of the quality of the humidifying water (see clause B.1). The tem
25、perature tolerance of 2 C is intended to take account of absolute errors in the measurement, fluctuations of the chamber temperature at any point and variations between any two points within the working space. However, in order to maintain the relative humidity within the specified tolerance of 5 %,
26、 it is necessary to keep the difference between any two points in the working space (at any instant) within narrower limits. The specified humidity tolerance will be exceeded if such temperature differences exceed 1,5 C. It is also necessary to restrict the short-term temperature fluctuations due to
27、 cycling of the chamber heater to a similar value. The specimen should not significantly impede the air flow. Condensation shall not be allowed to form on the specimen at any time during the test. 3.2 The humidifying water Distilled or deionised water shall be used. The water shall have a resistivit
28、y of not less than 0,5 M7cm at23 C. The pH value shall be between 6,0 and7,2at 23 C. Before the water is placed in the humidifier, all internal parts of the chamber shall be cleaned. Guidance on cleaning is given in clause B.3. The humidifier and/or test chamber shall be purged of all water after ea
29、ch test. 4 Severities The test severity, defined by the duration, shall be defined in the relevant specification. Unless otherwise specified, one of the durations given in Table 1 shall be used. EN 60068-2-67:1996 4 BSI 07-1999 Table 1 Severities 5 Pre-conditioning The relevant specification may pre
30、scribe pre-conditioning 6 Initial measurements The specimen shall be submitted to the visual, dimensional and functional checks prescribed by the relevant specification. 7 Testing 7.1 With the chamber and specimen at the laboratory conditions of temperature, pressure and humidity, the specimen shall
31、 be installed in the working space in the chamber. 7.2 The specimen shall not be subjected to radiant heat from the heaters or the chamber wall. If required by the relevant specification, a specific mounting structure shall be used. The heat conductivity and the thermal capacity of the mounting fixt
32、ures shall be sufficiently low so that for all practical purposes the specimen is thermally isolated. Care shall be exercised in the choice of mounting structure and mounting fixture materials to minimise the effects of contamination and to minimise degradation due to corrosion and other mechanisms
33、(see clause B.1). 7.3 If required by the relevant specification the specimen shall have a bias voltage applied during testing. Guidance on the application of bias is given in clause B.2. The bias voltage (or bias voltage cycle) shall be applied to the specimen when the temperature and the relative h
34、umidity have reached the stable state and continue until the specimen is under recovery conditions. 7.4 Test cycle 7.4.1 The temperature and relative humidity of the chamber shall be raised to their appropriate values. During this period the temperature and the relative humidity shall not exceed the
35、 specified value. Condensed water is not allowed on the specimen at any time during the test cycle. Stabilisation of temperature and humidity shall take place within3h. 7.4.2 The temperature and relative humidity shall be maintained within the prescribed limits for a duration as specified in the rel
36、evant specification. The duration shall commence as soon as the conditions have stabilised. 7.4.3 At the end of the specified duration, the chamber temperature and relative humidity shall be restored to standard atmospheric conditions for measurement and tests in not less than 1 h and not more than
37、4 h. During this period, the temperature and the relative humidity shall not exceed the specified value. The bias shall be maintained during this period. 7.4.4 On completion of the cooling period the specimen shall be subjected to the recovery procedure. 8 Intermediate measurements The relevant spec
38、ification may require electrical and/or mechanical checks during testing. Temperature Relative humidity Duration cd h C a % b I II III IV 85 85 168 504 1 000 2 000 NOTEIt is not recommended that a test should be restarted; however if it is required to subject the specimen to a longer duration than 2
39、 000 h then the test shall be recommenced in accordance with the requirements of clause 7. The test shall be recommenced within 96 h of the end of the ramp-down period of the previous test. During the interval between the tests the specimen shall be held under standard atmospheric conditions for mea
40、surement and tests, unless otherwise specified in the relevant specification. a Tolerance for temperature: 2 C in the chamber working space b Tolerance for relative humidity: 5 % c Tolerance for duration: d Definition of duration:see 7.4.2 5 +0%EN60068-2-67:1996 BSI 07-1999 5 If it is required to ma
41、ke intermediate measurements, the relevant specification shall define the measurements and period(s) during testing after which they shall be carried out. The measurements shall not cause any change to the test conditions. Measurements preceded by recovery which would require removal of the specimen
42、 from the chamber are not permissible during testing. 9 Recovery Upon completion of testing the specimen shall be allowed to recover. Unless otherwise specified in the relevant specification, recovery shall be not less than 2 h and not more than 24 h at standard atmospheric conditions for measuremen
43、t and tests. 10 Final measurements The specimen shall be submitted to the visual, dimensional, and functional checks prescribed by the relevant specification. 11 Information to be given in the relevant specification When this test is included in a relevant specification, the following details shall
44、be given, in so far as they are applicable. The relevant specification shall supply information as required in the clauses listed below, paying particular attention to the items marked with an asterisk (*), as this information is always required. Clause/subclause a) Test severity (duration)* 4 b) At
45、mospheric conditions between tests (if not standard) 4 c) Pre-conditioning* 5 d) Initial measurements* 6 e) Specific mounting structures 7.2 f) Bias voltage 7.3 and B.2 g) Intermediate measurements 8 h) Recovery* 9 I) Final measurements* 10EN 60068-2-67:1996 6 BSI 07-1999 Annex A (informative) Physi
46、cal significance of the test A.1 The acceleration of the penetration of water-vapour into the specimen is the most important physical factor in the accelerated damp heat test. The acceleration is due to the difference in partial pressure of water-vapour between the inside of a non-hermetically seale
47、d specimen and the test environment. A.2 In the first instance this test was applied to accelerate the corrosion of aluminium metallisation in both integrated circuits and other semiconductor devices in plastic encapsulation. However, when considering the application of the test to other products it
48、 is important that the failure mode or modes are determined, and the appropriate degradation process and test severity selected in response to each failure mode. Annex B (informative) Test apparatus and handling B.1 Selection of materials Care exercised in the choice of materials to be used in the c
49、hamber will minimise the release of contamination and the degradation due to corrosion and other mechanisms under the combined conditions of humidity and temperature defined in the test. Suitable materials are: stainless steel, glass, ceramic, and others which resist corrosion. B.2 Bias voltage Bias voltage is defined as that voltage which is applied for test purposes in order to enhance the effects of humidity. It is not necessarily concerned with the normal functioning of the specimen. The bias should be applied in accor
