1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationEnvironmental testingPart 2-65: Tests Test Fg: Vibration Acoustically induced methodBS EN 60068-2-65:2013National forewordThis British Standard is the UK implementation of EN 600
2、68-2-65:2013. It isidentical to IEC 60068-2-65:2013. It supersedes BS EN 60068-2.65:1995which is withdrawn.The UK participation in its preparation was entrusted to Technical CommitteeGEL/104, Environmental conditions, classification and testing.A list of organizations represented on this committee c
3、an be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application. The British Standards Institution 2013Published by BSI Standards Limited 2013ISBN 978 0 580 52984 9ICS 19.040Compliance
4、 with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of the StandardsPolicy and Strategy Committee on 31 May 2013.Amendments issued since publicationAmd. No. Date Text affectedBRITISH STANDARDBS EN 60068-2-65:2013EUROPEAN STAND
5、ARD EN 60068-2-65 NORME EUROPENNE EUROPISCHE NORM May 2013 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Management Centre: Avenue Marnix 17, B - 1000 Brussels 2013 CENELEC - All rights
6、 of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60068-2-65:2013 E ICS 19.040; 29.020 Supersedes EN 60068-2-65:1994 English version Environmental testing - Part 2-65: Tests - Test Fg: Vibration - Acoustically induced method (IEC 60068-2-65:2013) Essai
7、s denvironnement - Partie 2-65: Essais - Essai Fg: Vibrations - Mthode induite acoustiquement (CEI 60068-2-65:2013) Umgebungseinflsse - Teil 2-65: Prfverfahren - Prfung Fg: Schwingen - akustisch angeregt (IEC 60068-2-65:2013) This European Standard was approved by CENELEC on 2013-03-13. CENELEC memb
8、ers 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 applicati
9、on 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
10、 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, Icelan
11、d, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 60068-2-65:2013EN 60068-2-65:2013 - 2 - Foreword The text of document 104/591/FDIS, future edition 2 of IE
12、C 60068-2-65, 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 60068-2-65:2013. The following dates are fixed: latest date by which the document has to be implemented at national level b
13、y publication of an identical national standard or by endorsement (dop) 2013-12-13 latest date by which the national standards conflicting with the document have to be withdrawn (dow) 2016-03-13 This document supersedes EN 60068-2-65:1994. EN 60068-2-65:2013 includes the following significant techni
14、cal changes with respect to EN 60068-2-65:1994: minor technical and editorial changes were made throughout the document as originally requested by the DE National Committee; following comments at the CD stage, particularly from the UK National Committee, significant technical and editorial additions
15、 were made to the standard for acoustic testing employing the progressive wave tube technique. 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
16、 rights. Endorsement notice The text of the International Standard IEC 60068-2-65:2013 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliography, the following notes have to be added for the standards indicated: IEC 60068-1 NOTE Harmonized as
17、EN 60068-1. ISO 266 NOTE Harmonized as EN ISO 266. BS EN 60068-2-65:2013- 3 - EN 60068-2-65:2013 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 doc
18、ument 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
19、 by (mod), the relevant EN/HD applies. Publication Year Title EN/HD Year IEC 61672-1 - Electroacoustics - Sound level meters - Part 1: Specifications EN 61672-1 - ISO/IEC 17025 2005 General requirements for the competence of testing and calibration laboratories EN ISO/IEC 17025 2005 BS EN 60068-2-65
20、:2013 2 60068-2-65 IEC:2013 CONTENTS INTRODUCTION . 6 1 Scope . 7 2 Normative references 7 3 Terms, definitions, symbols and abbreviations. 7 3.1 Terms and definitions 7 3.2 Symbols and abbreviations 11 4 Acoustic environments and requirements for testing 11 4.1 Acoustic environment for testing 11 4
21、.1.1 General . 11 4.1.2 Reverberant field . 13 4.1.3 Progressive wave field . 14 4.1.4 Cavity resonance . 14 4.1.5 Standing wave . 14 4.2 Sound sources . 14 4.3 Measuring apparatus . 14 4.3.1 General . 14 4.3.2 Acoustic measurements . 14 4.3.3 Vibration response measurements . 15 4.3.4 Analysis of r
22、esults 15 4.4 Requirements for testing 15 4.4.1 Type of facility . 15 4.4.2 Mounting 15 4.4.3 Specimen instrumentation 16 4.4.4 Preparation of test control 17 5 Recommended severities 18 6 Preconditioning . 18 7 Initial measurements . 19 8 Testing . 19 8.1 Normal testing . 19 8.2 Accelerated testing
23、 19 9 Intermediate measurements 19 10 Recovery 19 11 Final measurements . 19 12 Information to be given in the relevant specification . 20 13 Information to be given in the test report . 20 Annex A (informative) Guidance for the test requirements. 22 Bibliography 30 Figure 1 Third-octave band spectr
24、um for aeronautical applications . 12 Figure 2 Octave band spectra for fans derived from 4 . 13 Figure 3 Octave band spectrum for noisy industrial machinery derived from 4 . 13 Figure 4 Typical locations of microphone checkpoints (1 6) on a fictitious surface around a specimen 17 BS EN 60068-2-65:20
25、1360068-2-65 IEC:2013 3 Figure A.1 Typical microphone arrangement around a specimen in a reverberation chamber 22 Figure A.2 Typical microphone checkpoint arrangement around a long cylindrical specimen 25 Table 1 Tolerances for acoustic measurement 14 Table 2 Overall sound pressure level and duratio
26、n of exposure . 18 Table A.1 Octave band/room volume relationship . 23 Table A.2 Reverberation room, ratios of dimensions . 23 Table A.3 Examples of sound sources with waveforms and typical power outputs 28 Table A.4 Typical OASPL and exposure durations 28 BS EN 60068-2-65:2013 6 60068-2-65 IEC:2013
27、 INTRODUCTION Acoustic noise may produce significant vibration in components and equipment. In the acoustic noise field, sound pressure fluctuations impinge directly on the specimen and the response may be different to that produced by mechanical excitation. Items particularly sensitive to acoustic
28、noise include relatively lightweight items whose dimensions are comparable to an acoustic wavelength in the frequency range of interest and whose mass per unit area is low, such as dish antennas and solar panels, electronic devices, printed circuit boards, optical elements, etc. Acoustic testing is
29、applicable to components, equipment, functional units and other products, hereinafter referred to as “specimens”, which are liable to be exposed to and/or are required to function in conditions of high sound pressure levels. It should be noted that, under service conditions, the specimen may be subj
30、ected to simultaneous mechanical and acoustical excitation. High sound pressure levels may be generated by jet engines and other aircraft propulsion systems, rocket motors, high-powered gas circulators, turbulent gas flow around aircraft or launchers, etc. This part of IEC 60068 deals with acoustic
31、testing in compressible gases and can also be used to simulate the excitation response caused by turbulence resulting from high-velocity separated gas flows. The intent of the test procedure contained in this standard is to produce a high intensity acoustic noise field by either reverberant methods
32、(known as reverberant chamber testing) or by progressive wave methods (known as progressive wave tube testing). Testing for the effects of vibration caused by acoustic noise demands a certain degree of engineering judgement and this should be recognized both by the manufacturer/supplier and the purc
33、haser of the specimen. Based on the guidance provided in this standard, the writer of the relevant specification is expected to select the most appropriate method of test and values of severity, taking account of the nature of the specimen and its intended use. Since the acoustic levels occurring du
34、ring testing are high enough to be damaging to human hearing, appropriate protective measures need to be taken to reduce the noise exposure of operators performing the test to a level regarded as permissible from the standpoint of hearing conservation. BS EN 60068-2-65:201360068-2-65 IEC:2013 7 ENVI
35、RONMENTAL TESTING Part 2-65: Tests Test Fg: Vibration Acoustically induced method 1 Scope This part of IEC 60068 provides standard procedures and guidance for conducting acoustic tests in order to determine the ability of a specimen to withstand vibration caused by a specified sound-pressure level e
36、nvironment to which it is, or is liable to be, subjected. For sound pressure level environments of less than 120 dB acoustic tests are not normally required. This standard determines the mechanical weakness and/or degradation in the performance of specimens and to use this information, in conjunctio
37、n with the relevant specification, to decide on their acceptability for use. The methods of test may also be used as a means of establishing the mechanical robustness or fatigue resistance of specimens. Two procedures are described for conducting tests and for measurement of the sound pressure level
38、s within the acoustic noise field and considers the need for measurement of the vibration responses at specified points on the specimen. It also gives guidance for the selection of the acoustic noise environment, spectrum, sound pressure level and duration of exposure. The progressive wave tube meth
39、od is relevant to material where aerodynamic turbulence will excite part, or all, of the total external surface. Such applications include aircraft panel assemblies where the excitation exists on one side only. The reverberant chamber method is relevant where it is preferable to induce vibration ont
40、o the entire external surface of equipment by distributed excitation rather than fixed points by means of electro-dynamic shakers. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated ref
41、erences, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 61672-1, Electroacoustics Sound level meters Part 1: Specifications ISO/IEC 17025:2005, General requirements for the competence of testing and calibr
42、ation laboratories 3 Terms, definitions, symbols and abbreviations 3.1 Terms and definitions For the purposes of this document, the following terms and definitions apply. BS EN 60068-2-65:2013 8 60068-2-65 IEC:2013 3.1.1 acoustic horn tube with increasing cross-section of generally exponential envel
43、ope, used to couple an acoustic source to the test volume, for example the inside of a reverberation room, thus achieving the maximum transfer of sound energy Note 1 to entry: Each acoustic horn has individual transfer characteristics which affect the sound spectrum. 3.1.2 analysis integration time
44、time duration over which a signal is averaged Note 1 to entry: See Clause A.8. 3.1.3 bandwidth difference between the nominal upper and lower cut-off frequencies Note 1 to entry: It may be expressed a) in hertz, b) as a percentage of the pass-band centre frequency, or c) as the interval between the
45、upper and lower nominal cut-off frequencies in octaves. 3.1.4 overall sound pressure level OASPL value computed from the third-octave or octave band sound pressure levels LiLG= 10 log10=mL110/i10iwhere LGis the overall sound pressure level in dB; Liis the sound pressure level in the ith third-octave
46、 or octave band; m is the number of third-octave or octave bands. 3.1.5 centre frequency geometric mean of the nominal cut-off frequencies of a pass-band Note 1 to entry: The nominal upper and lower cut-off frequencies of a filter pass-band are defined as those frequencies above and below the freque
47、ncy of maximum response of a filter at which the response to a sinusoidal signal is 3 dB below the maximum response. Note 2 to entry: The geometric mean is equal to (f1 f2), where f1and f2are the cut-off frequencies. 3.1.6 constant-bandwidth filter filter which has a bandwidth of constant value when
48、 expressed in hertz; it is independent of the centre frequency of the filter 3.1.7 cut-off frequency (of acoustic horn) frequency below which an acoustic horn becomes increasingly ineffective Note 1 to entry: This cut-off frequency is a main characteristic of an acoustic horn. BS EN 60068-2-65:20136
49、0068-2-65 IEC:2013 9 3.1.8 diffuse sound field sound field which, in a given region, has statistically uniform energy density, for which the directions of propagation at any point are randomly distributed Note 1 to entry: In a diffuse sound field, the sound pressure level measured with a directional microphone would give the same results whatever its orientation. SOURCE: IEC 60050-801:1994 11, definition 801-23-31, modified Addition of the Note 1 to entry 3.1.9 el
