1、 IEC 60118-4 Edition 3.0 2014-12 INTERNATIONAL STANDARD NORME INTERNATIONALE Electroacoustics Hearing aids Part 4: Induction-loop systems for hearing aid purposes System performance requirements lectroacoustique Appareils de correction auditive Partie 4: Systmes de boucles dinduction utilises des fi
2、ns de correction auditive Exigences de performances systme IEC 60118-4:2014-12(en-fr) colour inside THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright 2014 IEC, Geneva, Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form o
3、r by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either IEC or IECs member National Committee in the country of the requester. If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this
4、publication, please contact the address below or your local IEC member National Committee for further information. Droits de reproduction rservs. Sauf indication contraire, aucune partie de cette publication ne peut tre reproduite ni utilise sous quelque forme que ce soit et par aucun procd, lectron
5、ique ou mcanique, y compris la photocopie et les microfilms, sans laccord crit de lIEC ou du Comit national de lIEC du pays du demandeur. Si vous avez des questions sur le copyright de lIEC ou si vous dsirez obtenir des droits supplmentaires sur cette publication, utilisez les coordonnes ci-aprs ou
6、contactez le Comit national de lIEC de votre pays de rsidence. IEC Central Office Tel.: +41 22 919 02 11 3, rue de Varemb Fax: +41 22 919 03 00 CH-1211 Geneva 20 infoiec.ch Switzerland www.iec.ch About the IEC The International Electrotechnical Commission (IEC) is the leading global organization tha
7、t prepares and publishes International Standards for all electrical, electronic and related technologies. About IEC publications The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the latest edition, a corrigenda or an amendment might h
8、ave been published. IEC Catalogue - webstore.iec.ch/catalogue The stand-alone application for consulting the entire bibliographical information on IEC International Standards, Technical Specifications, Technical Reports and other documents. Available for PC, Mac OS, Android Tablets and iPad. IEC pub
9、lications search - www.iec.ch/searchpub The advanced search enables to find IEC publications by a variety of criteria (reference number, text, technical committee,). It also gives information on projects, replaced and withdrawn publications. IEC Just Published - webstore.iec.ch/justpublished Stay up
10、 to date on all new IEC publications. Just Published details all new publications released. Available online and also once a month by email. Electropedia - www.electropedia.org The worlds leading online dictionary of electronic and electrical terms containing more than 30 000 terms and definitions i
11、n English and French, with equivalent terms in 14 additional languages. Also known as the International Electrotechnical Vocabulary (IEV) online. IEC Glossary - std.iec.ch/glossary More than 55 000 electrotechnical terminology entries in English and French extracted from the Terms and Definitions cl
12、ause of IEC publications issued since 2002. Some entries have been collected from earlier publications of IEC TC 37, 77, 86 and CISPR. IEC Customer Service Centre - webstore.iec.ch/csc If you wish to give us your feedback on this publication or need further assistance, please contact the Customer Se
13、rvice Centre: csciec.ch. A propos de lIEC La Commission Electrotechnique Internationale (IEC) est la premire organisation mondiale qui labore et publie des Normes internationales pour tout ce qui a trait llectricit, llectronique et aux technologies apparentes. A propos des publications IEC Le conten
14、u technique des publications IEC est constamment revu. Veuillez vous assurer que vous possdez ldition la plus rcente, un corrigendum ou amendement peut avoir t publi. Catalogue IEC - webstore.iec.ch/catalogue Application autonome pour consulter tous les renseignements bibliographiques sur les Normes
15、 internationales, Spcifications techniques, Rapports techniques et autres documents de lIEC. Disponible pour PC, Mac OS, tablettes Android et iPad. Recherche de publications IEC - www.iec.ch/searchpub La recherche avance permet de trouver des publications IEC en utilisant diffrents critres (numro de
16、 rfrence, texte, comit dtudes,). Elle donne aussi des informations sur les projets et les publications remplaces ou retires. IEC Just Published - webstore.iec.ch/justpublished Restez inform sur les nouvelles publications IEC. Just Published dtaille les nouvelles publications parues. Disponible en li
17、gne et aussi une fois par mois par email. Electropedia - www.electropedia.org Le premier dictionnaire en ligne de termes lectroniques et lectriques. Il contient plus de 30 000 termes et dfinitions en anglais et en franais, ainsi que les termes quivalents dans 14 langues additionnelles. Egalement app
18、el Vocabulaire Electrotechnique International (IEV) en ligne. Glossaire IEC - std.iec.ch/glossary Plus de 55 000 entres terminologiques lectrotechniques, en anglais et en franais, extraites des articles Termes et Dfinitions des publications IEC parues depuis 2002. Plus certaines entres antrieures ex
19、traites des publications des CE 37, 77, 86 et CISPR de lIEC. Service Clients - webstore.iec.ch/csc Si vous dsirez nous donner des commentaires sur cette publication ou si vous avez des questions contactez-nous: csciec.ch. IEC 60118-4 Edition 3.0 2014-12 INTERNATIONAL STANDARD NORME INTERNATIONALE El
20、ectroacoustics Hearing aids Part 4: Induction-loop systems for hearing aid purposes System performance requirements lectroacoustique Appareils de correction auditive Partie 4: Systmes de boucles dinduction utilises des fins de correction auditive Exigences de performances systme INTERNATIONAL ELECTR
21、OTECHNICAL COMMISSION COMMISSION ELECTROTECHNIQUE INTERNATIONALE XA ICS 17.140.50 PRICE CODE CODE PRIX ISBN 978-2-8322-1984-3 Registered trademark of the International Electrotechnical Commission Marque dpose de la Commission Electrotechnique Internationale Warning! Make sure that you obtained this
22、publication from an authorized distributor. Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agr. colour inside 2 IEC 60118-4:2014 IEC 2014 CONTENTS FOREWORD . 6 INTRODUCTION . 8 1 Scope 9 2 Normative references 9 3 Terms and definitions 9 4 General . 10 4.
23、1 Procedure for setting up and commissioning an audio-frequency induction loop system 10 4.2 Suitability of the site for the installation of an audio-frequency induction-loop system 10 4.3 Relation of the magnetic field strength level at the telecoil to the sound pressure level at the microphone. .
24、11 5 Using components of a sound system in an induction-loop system 11 5.1 General . 11 5.2 Microphones . 11 5.3 Mixer 11 5.4 Power amplifier . 11 6 Meters and test signals 11 6.1 Meters 11 6.1.1 Meters in general . 11 6.1.2 Requirements common to both types . 11 6.1.3 True-r.m.s. meter . 12 6.1.4 P
25、eak programme meter (PPM) . 12 6.2 Test signals in general 12 6.3 Speech signals . 13 6.3.1 Live speech signals . 13 6.3.2 Recorded speech material . 13 6.3.3 Simulated speech material . 13 6.4 Pink noise signal . 13 6.5 Sinusoidal signal . 13 6.6 Combi signal . 14 7 Magnetic background noise level
26、of the installation site . 14 7.1 Method of measurement . 14 7.2 Recommended maximum magnetic noise levels 15 8 Characteristics to be specified, methods of measurement and requirements 15 8.1 General . 15 8.2 Magnetic field strength 16 8.2.1 Characteristic to be specified . 16 8.2.2 Method of measur
27、ement with a simulated speech signal 16 8.2.3 Method of measurement with pink noise 17 8.2.4 Method of measurement with a sinusoidal signal . 17 8.2.5 Method of measurement with a combi signal 17 8.2.6 Method of measurement Other 17 8.2.7 Requirements 17 8.3 Frequency response of the magnetic field
28、. 18 8.3.1 Characteristic to be specified . 18 IEC 60118-4:2014 IEC 2014 3 8.3.2 Method of measurement with a simulated speech signal 18 8.3.3 Method of measurement with pink noise 18 8.3.4 Method of measurement with a sinusoidal signal . 18 8.3.5 Method of measurement with combi signal . 19 8.3.6 M
29、ethod of measurement Other 19 8.3.7 Requirements 19 8.4 Useful magnetic field volume 19 8.4.1 Characteristic to be specified . 19 8.4.2 Methods of measurement 19 8.4.3 Requirements 19 9 Small-volume systems . 19 9.1 Inapplicability of the useful magnetic field volume concept 19 9.2 Disabled refuge a
30、nd similar call-points 20 9.3 Requirements for disabled refuge and similar call-points . 22 9.4 Counter systems . 22 9.5 Requirements for counter systems 24 10 Setting up (commissioning) the system 24 10.1 Procedure . 24 10.2 Magnetic noise level due to the system . 24 10.2.1 Explanation of term 24
31、10.2.2 Method of measurement with a speech signal 24 10.2.3 Method of measurement with pink noise 25 10.2.4 Method of measurement with a sinusoidal signal . 25 10.2.5 Method of measurement with a combi signal 25 10.2.6 Method of measurement Other (no input signal) 25 10.2.7 Requirements 25 10.3 Ampl
32、ifier overload at 1,6 kHz 25 10.3.1 Explanation of term 25 10.3.2 Methods of test 25 10.4 Requirements . 25 Annex A (informative) Systems for small useful magnetic field volumes . 27 A.1 Overview. 27 A.2 Body-worn audio systems . 27 A.3 Small volume, defined seating, mainly in households 27 A.4 Spec
33、ific locations such as help and information points, ticket and bank counters, etc. 27 Annex B (informative) Measuring equipment 30 B.1 Overview. 30 B.2 Signal sources 30 B.2.1 Real speech 30 B.2.2 Simulated speech 30 B.2.3 Pink noise 30 B.2.4 Sine wave 30 B.3 Magnetic field strength level meter 31 B
34、.3.1 General recommendations . 31 B.3.2 Peak-programme meter (PPM) type . 31 B.3.3 True r.m.s. meter type . 31 B.4 Field strength level meter calibrator 32 B.5 Spectrum analyzer 32 4 IEC 60118-4:2014 IEC 2014 Annex C (informative) Provision of information. 33 C.1 General . 33 C.2 Information to be p
35、rovided to the hearing aid user 33 C.3 Information to be provided to system installers and by them to users 34 C.4 Information to be provided by the manufacturer of the amplifying equipment . 34 Annex D (informative) Measuring speech signals . 35 Annex E (informative) Basic theory and practice of au
36、dio-frequency induction-loop systems 36 E.1 Properties of the loop and its magnetic field 36 E.2 Directional response of the telecoil of a hearing aid 37 E.3 Supplying the loop current 42 E.4 Signal sources and cables 43 E.4.1 Microphones 43 E.4.2 Other signal sources 44 E.4.3 Cables . 44 E.5 Care o
37、f the system 44 E.6 Magnetic units 44 Annex F (informative) Effects of metal in the building structure on the magnetic field . 45 Annex G (informative) Calibration of field-strength meters . 47 Annex H (informative) Effect of the aspect ratio of the loop on the magnetic field strength 49 H.1 Overvie
38、w. 49 H.2 Effect of aspect ratio on field patterns . 49 Annex I (informative) Overspill of magnetic field from an induction-loop system . 51 I.1 General . 51 I.2 Examples of overspill issues . 51 I.3 Addressing overspill issues . 51 Bibliography 53 Figure 1 Flow chart for the operations in this stan
39、dard . 10 Figure 2 Measurement points for disabled refuge and similar call-points 21 Figure 3 Measurement points for a counter system 23 Figure A.1 Field pattern of a vertical loop . 28 Figure A.2 Contour plot of field strength of vertical loop . 29 Figure C.1 Graphical symbol: inductive coupling 33
40、 Figure E.1 Perspective view of a loop, showing the magnetic field vector paths . 37 Figure E.2 Strengths of the components of the magnetic field due to current in a horizontal rectangular loop at points in a plane above or below the loop plane 38 Figure E.3 Field patterns of the vertical component
41、of the magnetic field of a horizontal loop 39 Figure E.4 Field patterns of the vertical component of the magnetic field of a vertical loop 0,75 m square . 40 Figure E.5 Perspective view of the variation of the vertical field strength level at an optimum height above a horizontal rectangular loop 41
42、Figure E.6 Directional response of the magnetic pick-up coil (telecoil) of a hearing aid 42 Figure F.1 Magnetic field pattern of a 10 m by 14 m loop, 1,2 m above its plane 45 IEC 60118-4:2014 IEC 2014 5 Figure F.2 Magnetic field pattern of a 10 m by 14 m loop, 1,2 m above its plane, showing the effe
43、ct of metal (iron) in the floor 46 Figure G.1 Triple Helmholtz coil for calibration of meters . 47 Figure H.1 Variation of the current required to produce a specified magnetic field strength at a specific point with the dimensions and aspect ratio of the loop . 49 Figure H.2 Square and rectangular l
44、oops . 50 Table 1 Application of signals 12 Table 2 Specification of the combi signal . 14 Table 3 Magnetic field strengths typically produced by different test signals, with an amplifier having peak-detecting AGC 17 6 IEC 60118-4:2014 IEC 2014 INTERNATIONAL ELECTROTECHNICAL COMMISSION _ ELECTROACOU
45、STICS HEARING AIDS Part 4: Induction-loop systems for hearing aid purposes System performance requirements FOREWORD 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). Th
46、e object of IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specif
47、ications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non- governmental organizations
48、 liaising with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decisions or agreements of IEC on technical matters e
49、xpress, as nearly as possible, an international consensus of opinion on the relevant subjects since each technical committee has representation from all interested IEC National Committees. 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While all reasonable efforts are made to ensure that t
