prEN IEC 60068-2-78:2024

SLOVENSKI STANDARD
01-junij-2024
Okoljsko preskušanje - 2-78. del: Preskusi - Preskuševalna omarica: vlažna
vročina, ustaljeno stanje
Environmental testing - Part 2-78: Tests - Test cab: Damp heat, steady state
Umgebungseinflüsse - Teil 2-78: Prüfverfahren - Prüfung Cab: Feuchte Wärme, konstant
Essais d'environnement - Partie 2-78: Essais - Essai cab: Chaleur humide, essai continu
Ta slovenski standard je istoveten z: prEN IEC 60068-2-78:2024
ICS:
19.040 Preskušanje v zvezi z Environmental testing
okoljem
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

104/1049/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 60068-2-78 ED3
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2024-04-19 2024-07-12
SUPERSEDES DOCUMENTS:
104/1019/CD, 104/1030C/CC
IEC TC 104 : ENVIRONMENTAL CONDITIONS, CLASSIFICATION AND METHODS OF TEST
SECRETARIAT: SECRETARY:
Sweden Mr Henrik Lagerström
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:

Other TC/SCs are requested to indicate their interest, if
any, in this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
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This document is still under study and subject to change. It should not be used for reference purposes.
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the final stage for submitting ISC clauses. (SEE AC/22/2007 OR NEW GUIDANCE DOC).

TITLE:
Environmental testing - Part 2-78: Tests - Test Cab: Damp heat, steady state

PROPOSED STABILITY DATE: 2031
NOTE FROM TC/SC OFFICERS:
download this electronic file, to make a copy and to print out the content for the sole purpose of preparing National
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1 CONTENTS
3 FOREWORD . 3
4 INTRODUCTION . 5
5 1 Scope . 6
6 2 Normative references . 6
7 3 Terms and definitions . 6
8 4 General test procedure . 6
9 General . 6
10 Description of test chamber . 7
11 Severity . 7
12 Pre-conditioning . 8
13 Testing procedure . 9
14 Recovery procedure . 12
15 5 Measurements . 12
16 Initial measurements . 12
17 Intermediate measurements . 12
18 Final measurements . 12
19 6 Information to be given in the relevant specification. 12
20 7 Information to be given in the test report . 13
21 Bibliography . 14
23 Table 1 – Preferred values for the temperature and relative humidity . 8
25 Figure 1 - Exemplary pre-conditioning phases with transition to the conditioning
26 periods for Method II (a) and Method IV (b) . 9
27 Figure 2 – Test Cab – Method I . 10
28 Figure 3 – Test Cab – Method II . 10
29 Figure 4 – Test Cab – Method III . 11
30 Figure 5 – Test Cab – Method IV . 11
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33 INTERNATIONAL ELECTROTECHNICAL COMMISSION
34 ____________
36 ENVIRONMENTAL TESTING –
38 Part 2-78: Tests – Test Cab: Damp heat, steady state
40 FOREWORD
41 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
42 all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
43 co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
44 in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
45 Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
46 preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
47 may participate in this preparatory work. International, governmental and non-governmental organizations liaising
48 with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
49 Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
50 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
51 consensus of opinion on the relevant subjects since each technical committee has representation from all
52 interested IEC National Committees.
53 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
54 Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
55 Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
56 misinterpretation by any end user.
57 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
58 transparently to the maximum extent possible in their national and regional publications. Any divergence between
59 any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
60 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
61 assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
62 services carried out by independent certification bodies.
63 6) All users should ensure that they have the latest edition of this publication.
64 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
65 members of its technical committees and IEC National Committees for any personal injury, property damage or
66 other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
67 expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.
68 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
69 indispensable for the correct application of this publication.
70 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
71 rights. IEC shall not be held responsible for identifying any or all such patent rights.
72 International Standard IEC 60068-2-78 has been prepared by technical committee 104:
73 Environmental conditions, classification, and methods of test.
74 This third edition cancels and replaces the second edition, published in 2012 and constitutes a
75 technical revision.
76 The major changes with regard to the previous edition concern:
77 a) revision of the requirements for the test chamber;
78 b) revision of the severities and including the dew point temperatures;
79 c) revision of the temperature tolerances of the test;
80 d) including a specified preconditioning procedure;
81 e) including a new figure for clarification purposes;
82 f) revision of standardized requirements for the test report.
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84 The text of this standard is based on the following documents:
FDIS Report on voting
xxx/xxx/xxxx xxx/xxx/xxx
86 Full information on the voting for the approval of this standard can be found in the report on
87 voting indicated in the above table.
88 This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
89 A list of all the parts in the IEC 60068 series, under the general title Environmental testing, can
90 be found on the IEC website.
91 The committee has decided that the contents of this publication will remain unchanged until the
92 stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data related to
93 the specific publication. At this date, the publication will be
94 • reconfirmed,
95 • withdrawn,
96 • replaced by a revised edition, or
97 • amended.
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99 INTRODUCTION
100 This part of IEC 60068 provides a test method of high humidity at constant temperature without
101 condensation on the specimen over a prescribed period. This test is performed to evaluate the
102 specimen as it is influenced by the absorption and diffusion of moisture and moisture vapor.
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104 ENVIRONMENTAL TESTING –
106 Part 2-78: Tests – Test Cab: Damp heat, steady state
108 1 Scope
109 This document establishes a test method for determining the ability of components or equipment
110 to withstand transportation, storage and use under conditions of high humidity.
111 The object of this standard is to investigate the effect of high humidity at constant temperature
112 without condensation on a specimen over a prescribed period.
113 It is applicable to small equipment or components as well as large equipment and can be applied
114 to both heat-dissipating and non-heat-dissipating specimens.
115 2 Normative references
116 The following documents are referred to in the text in such a way that some or all of their content
117 constitutes requirements of this document. For dated references, only the edition cited applies.
118 For undated references, the latest edition of the referenced document (including any
119 amendments) applies.
120 IEC 60068-1, Environmental testing – Part 1: General and guidance
121 IEC 60068-2-67, Environmental testing – Part 2-67: Tests – Test Cy: Damp heat, steady state,
122 accelerated test primarily intended for components
123 3 Terms and definitions
124 For the purposes of this document, the terms and definitions given in IEC 60068-1 apply.
125 No terms and definitions are listed in this document.
126 ISO and IEC maintain terminological databases for use in standardization at the following
127 addresses:
128 • IEC Electropedia: available at http://www.electropedia.org/
129 • ISO online browsing platform: available at http://www.iso.org/obp
130 4 General test procedure
131 General
132 Test Cab can be applied to both heat-dissipating and non-heat-dissipating specimens.
133 The temperature and relative humidity limits given in this document are intended to take into
134 account errors in the measurement, slow changes of temperature, and temperature variations
135 of the working space.
136 NOTE 1 For further information on the working space, see IEC 60068-3-6.

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137 The temperature and relative humidity refer to the control sensor of the test chamber, if not
138 specified otherwise.
139 The limits stated in this document do not take measurement uncertainty into consideration.
140 NOTE 2 These limits are valid for an empty test space during stabilized temperature/humidity conditions of the test.
141 In some conditions, where the specimen has a negligible impact on the chamber control, the
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