BS EN 60068-2-78:2013 BSI Standards Publication Environmental testing Part 2-78: Tests — Test Cab: Damp heat, steady state BRITISH STANDARD BS EN 60068-2-78:2013 National foreword This British Standard is the UK implementation of EN 60068-2-78:2013 It is identical to IEC 60068-2-78:2012 It supersedes BS EN 60068-2-78:2002, which will be withdrawn on December 2015 The UK participation in its preparation was entrusted to Technical Committee GEL/104, Environmental conditions, classification and testing A list of organizations represented on this committee can be obtained on request to its secretary This publication does not purport to include all the necessary provisions of a contract Users are responsible for its correct application © The British Standards Institution 2013 Published by BSI Standards Limited 2013 ISBN 978 580 72152 ICS 19.040; 29.020 Compliance with a British Standard cannot confer immunity from legal obligations This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 July 2013 Amendments/corrigenda issued since publication Date Text affected BS EN 60068-2-78:2013 EN 60068-2-78 EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM June 2013 ICS 19.040; 29.020 Supersedes EN 60068-2-78:2001 English version Environmental testing Part 2-78: Tests Test Cab: Damp heat, steady state (IEC 60068-2-78:2012) Essais d'environnement Partie 2-78: Essais Essai Cab: Chaleur humide, essai continu (CEI 60068-2-78:2012) Umgebungseinflüsse Teil 2-78: Prüfverfahren Prüfung Cab: Feuchte Wärme, konstant (IEC 60068-2-78:2012) This European Standard was approved by CENELEC on 2012-12-03 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 obtained on application to the CEN-CENELEC Management Centre 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 CEN-CENELEC Management Centre has the same status as the official versions CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung Management Centre: Avenue Marnix 17, B - 1000 Brussels © 2013 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members Ref No EN 60068-2-78:2013 E BS EN 60068-2-78:2013 EN 60068-2-78:2013 -2- Foreword The text of document 104/582/FDIS, future edition of IEC 60068-2-78, prepared by IEC/TC 104 "Environmental conditions, classification, and methods of test" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN 60068-2-78:2013 The following dates are fixed: • latest date by which the document has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2013-12-14 • latest date by which the national standards conflicting with the document have to be withdrawn (dow) 2015-12-03 This document supersedes EN 60068-2-78:2001 EN 60068-2-78:2013 includes EN 60068-2-78:2001: the following significant technical changes with respect to The test chamber from EN 60068-3-6 has been introduced Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent rights Endorsement notice The text of the International Standard IEC 60068-2-78:2012 was approved by CENELEC as a European Standard without any modification BS EN 60068-2-78:2013 EN 60068-2-78:2013 -3- Annex ZA (normative) Normative references to international publications with their corresponding European publications The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies Publication Year Title EN/HD Year IEC 60068-1 - Environmental testing Part 1: General and guidance EN 60068-1 - IEC 60068-3-6 - Environmental testing EN 60068-3-6 Part 3-6: Supporting documentation and guidance - Confirmation of the performance of temperature/humidity chambers - IEC Guide 104 - The preparation of safety publications and the use of basic safety publications and group safety publications - - –2– BS EN 60068-2-78:2013 60068-2-78 IEC:2012 CONTENTS INTRODUCTION Scope and object Normative references Terms and definitions General test procedure 4.1 Test chamber and measuring system 4.2 Severity 4.3 Pre-conditioning 4.4 Testing procedure 4.5 Recovery procedure Measurements 5.1 Initial measurements 5.2 Intermediate measurements 5.3 Final measurements Information to be given in the relevant specification Information to be given in the test report Table – Temperature and relative humidity BS EN 60068-2-78:2013 60068-2-78 IEC:2012 –5– INTRODUCTION This part of IEC 60068 provides a test method of high humidity at constant temperature without condensation on the specimen over a prescribed period This test is performed to evaluate the specimen as it is influenced by the absorption and diffusion of moisture and moisture vapour –6– BS EN 60068-2-78:2013 60068-2-78 IEC:2012 ENVIRONMENTAL TESTING – Part 2-78: Tests – Test Cab: Damp heat, steady state Scope and object This part of IEC 60068 establishes a test method for determining the ability of components or equipment to withstand transportation, storage and use under conditions of high humidity The object of this standard is to investigate the effect of high humidity at constant temperature without condensation on a specimen over a prescribed period It is applicable to small equipment or components as well as large equipment, and can be applied to both heat-dissipating and non-heat-dissipating specimens Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies IEC 60068-1, Environmental testing – Part 1:General and guidance IEC 60068-3-6, Environmental testing – Part 3-6: Supporting documentation and guidance – Confirmation of the performance of temperature and humidity chambers IEC Guide 104, The preparation of safety publications and the use of basic safety publications and group safety publications Terms and definitions None 4.1 General test procedure Test chamber and measuring system The temperature and humidity chamber shall be constructed and verified in accordance with specifications IEC 60068-3-6 The chamber and measuring system shall be such that – sensing devices can be located in the working space to monitor the temperature and humidity, NOTE For heat-dissipating specimens, the temperature and humidity near the specimen may be influenced by the effect of heat dissipation from the specimen – condensed water is drained from the chamber and not re-used unless purified, – no condensed water from the walls and roof of the test chamber can fall on the specimen(s), BS EN 60068-2-78:2013 60068-2-78 IEC:2012 –7– – water utilized to maintain humidity levels has electrical conductivity of not more than 20 µS/cm, – the specimen under test shall not be subjected to radiant heat from the chamber conditioning devices, – injected moisture, when applicable, is injected remotely from the specimen and without being directly on it, – the volume of the test chamber is at least five times the total volume of the specimen under test, – a mounting device, when used, has minimum influence on the heat and humidity exchanges between specimen and surrounding conditions, unless otherwise specified in the relevant specification 4.2 Severity The test severity is defined by a combination of temperature, relative humidity (RH) and total test duration Unless otherwise specified in the relevant specification, temperature and RH severities may be selected from the following: Table – Temperature and relative humidity Temperature °C Relative humidity % RH 30 ± 93 ± 30 ± 85 ± 40 ± 93 ± 40 ± 85 ± Preferred test durations are: 12 h, 16 h, 24 h; days, days, 10 days, 21 days or 56 days The total temperature tolerance of ± K is intended to take account of absolute errors in the measurement, slow changes of temperature and temperature variations of the working space However, in order to maintain the RH within the required tolerances, it is necessary to keep the temperature difference between any two points in the working space at any moment within narrower limits The required humidity conditions will not be achieved if such temperature differences exceed K It may also be necessary to keep short-term fluctuations within ± 0,5 K to maintain the required humidity 4.3 Pre-conditioning The relevant specification may call for pre-conditioning 4.4 Testing procedure The specimen shall be introduced into the chamber as required by the relevant specification The specimen shall be introduced in the unpacked, switched-off, ready-for-use state, or as otherwise specified in the relevant specification In certain cases the relevant specification may allow the introduction of the specimen in the chamber when this is already in the condition prescribed for the test; however, condensation on the specimen shall always be avoided This can be obtained for small specimens by preheating them to the chamber temperature Adjust the temperature in the chamber to the prescribed severity In order to avoid condensation on the specimen, control the specimen temperature or allow the specimen to reach the temperature first and then adjust the humidity in the chamber to the prescribed severity –8– BS EN 60068-2-78:2013 60068-2-78 IEC:2012 Adjust the humidity to the prescribed severity within a period of time of not more than h Expose the specimen to the test conditions and duration as specified in the relevant specification The duration is measured from the time the specified conditions are achieved The relevant specification shall define the operating conditions and the period (or periods) in which they shall be carried out After conditioning at the prescribed severity and before the final measurement, the recovery procedure shall be followed 4.5 Recovery procedure The relevant specification shall prescribe the recovery method and duration conditions are described in IEC 60068-1 Recovery Measurements 5.1 Initial measurements The specimen shall be visually inspected and electrically and mechanically checked, as required by the relevant specification 5.2 Intermediate measurements The relevant specification may call for measurements during the test procedure while the specimen is still in the chamber If such measurements are required, the relevant specification shall define the measurements and the period (periods) at which they shall be carried out For these measurements, the specimen shall not be removed from the chamber 5.3 Final measurements The specimen shall be visually inspected and electrically and mechanically checked, as required by the relevant specification Information to be given in the relevant specification The following details shall be given as far as they are applicable: a) preconditioning; b) initial measurements; c) details of mounting or supports; d) state of specimen (unpowered, powered, packaged, unpackaged, etc.); e) type of specimen – heat dissipating or non-heat dissipating; f) test severities and tolerances 1) temperature, 2) relative humidity, 3) duration; g) intermediate measurements; h) recovery conditions; i) final measurements; j) any deviation in procedure as agreed upon between customer and supplier BS EN 60068-2-78:2013 60068-2-78 IEC:2012 –9– Information to be given in the test report As a minimum, the test report shall contain the following information Items shown in parentheses are examples a) Customer (name and address) b) Test laboratory (name and address and details of accreditation – if any) c) Test dates (dates when test was run) d) Type of test (Cab) e) Purpose of test (development, qualification, etc.) f) Test standard, edition (IEC 60068-2-78:edition used) g) Relevant laboratory test procedure (code and object) h) Test specimen description (drawing, photo, quantity, build status, etc.) i) Test chamber identity (manufacturer, model number, unique identification, etc.) j) Performance of test apparatus (set point temperature control, air flow, etc.) k) Uncertainties of measuring system (uncertainties data) l) Calibration data (last and next due date) m) Initial, intermediate and final measurements (initial, intermediate and final measurements) n) Required severities (from relevant specification) o) Actual test conditions (measurement location, data, etc.) p) Performance of test specimens (results of functional tests, etc.) q) Observations during testing and actions taken (any pertinent observations) r) Summary of test (test summary) s) Distribution (distribution list) _ This page deliberately left blank This page deliberately left blank NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW British Standards Institution (BSI) BSI is the national body responsible for preparing British Standards and other standards-related publications, information and services BSI is incorporated by Royal Charter British Standards and other standardization products are published by BSI Standards Limited About us Revisions We bring together business, industry, government, consumers, innovators and others to shape their combined experience and expertise into standards -based solutions Our British Standards and other publications are updated by amendment or revision The knowledge embodied in our standards has been carefully assembled in a dependable format and refined through our open consultation process Organizations of all sizes and across all sectors choose standards to help them achieve their goals Information on standards We can provide you with the knowledge that your organization needs to succeed Find out more about British Standards by visiting our website at bsigroup.com/standards or contacting our Customer Services team or Knowledge Centre Buying standards You can buy and download PDF versions of BSI publications, including British and adopted European and international standards, through our website at bsigroup.com/shop, where hard copies can also be purchased If you need international and foreign standards from other Standards Development Organizations, hard copies can be ordered from our Customer Services team Subscriptions Our range of subscription services are designed to make using standards easier for you For further information on our subscription products go to bsigroup.com/subscriptions With British Standards Online (BSOL) you’ll have instant access to over 55,000 British and adopted European and international standards from your desktop It’s available 24/7 and is refreshed daily so you’ll always be up to date You can keep in touch with standards developments and receive substantial discounts on the purchase price of standards, both in single copy and subscription format, by becoming a BSI Subscribing Member PLUS is an updating service exclusive to BSI Subscribing Members You will automatically receive the latest hard copy of your standards when they’re revised or replaced To find out more about becoming a BSI Subscribing Member and the benefits of membership, please visit bsigroup.com/shop With a Multi-User Network Licence (MUNL) you are able to host standards publications on your intranet Licences can cover as few or as many users as you wish With updates supplied as soon as they’re available, you can be sure your documentation is current For further information, email bsmusales@bsigroup.com BSI Group Headquarters 389 Chiswick High Road London W4 4AL UK We continually improve the quality of our products and services to benefit your business If you find an inaccuracy or ambiguity within a British Standard or other BSI publication please inform the Knowledge Centre Copyright All the data, software and documentation set out in all British Standards and other BSI publications are the property of and copyrighted by BSI, or some person or entity that owns copyright in the information used (such as the international standardization bodies) and has formally licensed such information to BSI for commercial publication and use Except as permitted under the Copyright, Designs and Patents Act 1988 no extract may be reproduced, stored in a retrieval system or transmitted in any form or by any means – electronic, photocopying, recording or otherwise – without prior written permission from BSI Details and advice can be obtained from the Copyright & Licensing Department Useful Contacts: Customer Services Tel: +44 845 086 9001 Email (orders): orders@bsigroup.com Email (enquiries): cservices@bsigroup.com Subscriptions Tel: +44 845 086 9001 Email: subscriptions@bsigroup.com Knowledge Centre Tel: +44 20 8996 7004 Email: knowledgecentre@bsigroup.com Copyright & Licensing Tel: +44 20 8996 7070 Email: copyright@bsigroup.com