1、BRITISH STANDARD AEROSPACE SERIES BS EN 3745-305:2002 Fibres and cables, optical, aircraft use Test methods Part 305: Immunity to ambient light coupling The European Standard EN 3745-305:2002 has the status of a British Standard ICS 49.060 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COP
2、YRIGHT LAWBS EN 3745-305:2002 This British Standard, having been prepared under the direction of the Engineering Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 25 June 2002 BSI 25 June 2002 ISBN 0 580 39903 6 National forewor
3、d This British Standard is the official English language version of EN 3745-305:2002. The UK participation in its preparation was entrusted by Technical Committee ACE/6, Aerospace avionic electrical and fibre optic technology, to Subcommittee ACE/6/10, Aerospace fibre optic systems and equipment, wh
4、ich has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue
5、under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correc
6、t application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests infor
7、med; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 5, and a back cover. The BSI copyright date displayed in this document indicates when the document
8、was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN3745305 June2002 ICS49.060 Englishversion AerospaceseriesFibresandcables,optical,aircraftuseTest methodsPart305:Immunitytoambientlightcoupling SriearospatialeFibresetcblesoptiq
9、uesusage aronautiqueMthodesdessaisPartie305:Immunit decouplagelalumireambiante LuftundRaumfahrtFaseroptischeLeitungenfr LuftfahrzeugePrfverfahrenTeil305: Fremdlichteinkopplung ThisEuropeanStandardwasapprovedbyCENon1March2002. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipul
10、atetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,
11、German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Iceland,Irel
12、and,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Spain,Sweden,SwitzerlandandUnitedKingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2002CEN Allrightsofexploitationinanyformandbyanymeansreserved wo
13、rldwideforCENnationalMembers. Ref.No.EN3745305:2002EEN3745305:2002(E) 2 Foreword Thisdocument(EN3745305:2002)hasbeenpreparedbytheEuropeanAssociationofAerospace Manufacturers(AECMA). AfterenquiriesandvotescarriedoutinaccordancewiththerulesofthisAssociation,thisStandardhas receivedtheapprovaloftheNati
14、onalAssociationsandtheOfficialServicesofthemembercountriesof AECMA,priortoitspresentationtoCEN. ThisEuropeanStandardshallbegiventhestatusofanationalstandard,eitherbypublicationofanidentical textorbyendorsement,atthelatestbyDecember2002,andconflictingnationalstandardsshallbe withdrawnatthelatestbyDec
15、ember2002. AccordingtotheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsofthefollowing countriesareboundtoimplementthisEuropeanStandard:Austria,Belgium,CzechRepublic,Denmark, Finland,France,Germany,Greece,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway, Portugal,Spain,Swed
16、en,SwitzerlandandtheUnitedKingdom.EN3745305:2002(E) 3 1 Scope Thisstandardspecifiesamethodofmeasuringtheimmunityofopticalfibreorcabletothecouplingofpower comingfromanexternallightsource. 2 Normativesreferences ThisEuropeanStandardincorporatesbydatedorundatedreferenceprovisionsfromotherpublications.
17、Thesenormativereferencesarecitedattheappropriateplacesinthetextandthepublicationsarelisted hereafter.Fordatedreferences,subsequentamendmentstoorrevisionsofanyofthesepublicationsapplyto thisEuropeanStandardonlywhenincorporatedinitbyamendmentorrevision.Forundatedreferencesthe latesteditionofthepublica
18、tionreferredtoapplies. EN 3745100 AerospaceseriesFibresandcables,optical,aircraftuseTestmethods Part100:General 1) 3 Preparationofspecimens 3.1 Thespecimensshallbepreparedaccordingtotheproductstandard. Ifnotyetatstandardtestconditions,thespecimensshallbesubjectedtostandardtestconditionsand stabilize
19、dattheseconditionsfor24hasdefinedinEN3745100. 3.2 Unlessspecifiedinthetechnicalspecification,thefollowingdetailsshallbestated: typeandlengthofthespecimeninthelightproofelement; spectralcharacteristicsorcolortemperatureofthelightsource; minimumauthorizedlongtermbendradius; typeofapparatususedtoguaran
20、teetheminimumlongtermbendradius. 4 Apparatus Theapparatusshallcomprise: C amodulatorsettofrequencywhichisnotamultipleof50Hzor60Hz; D adetector; Di adiffuser; IS anintegrationsphere; LA alockingamplifiertoachievethedetectionmeasurement; LDS aLightDetectorSysteminaccordancewiththespectralcharacteristi
21、csofthelightsource; Le alens; LS aLightSource; T aterminatortoprovideanonreflectivetermination; aremovablelightproofelementallowingshieldingthespecimenfromthelight; aglasscylinderoralternativeapparatuswhosediameterisinaccordancewiththeminimum longtermbendradius; 1) Inpreparationatthedateofpublicatio
22、nofthisstandardEN3745305:2002(E) 4 Atypicalarrangementisshowninfigure1. Figure1 5 Method Themethodconsistsofmeasuringtheambientlightcoupledinthespecimenbytheuseofanintegrated sphere(seefigure1). 5.1 Procedure Installthespecimenoflength L,retainedatspecifiedbendradius,inthelightproofelement. Turnonth
23、eLS,C,D,LDSandLA. Insertthespecimenwiththeremovablelightproofelementintheintegratedsphere. AdjustthepowerofLSsothattheoutputpowerisclosetotheupperdetectionlimitsofDandthenmeasure theoutputpowers P 0 and P f . Removethelightproofelement. Ifnecessary,adjustthepowerofLSagainsothatnew Pvalue P 1 isequal
24、to P 0 . Measurethenewpower P c .EN3745305:2002(E) 5 P 0 = levelofopticalpowerlaunchedintotheintegrationsphereafterinsertionoftheremovablelight proofelementwiththespecimen P 1 = levelofopticalpowerlaunchedintotheintegrationsphereafterthelightproofelementhasbeen removed P f = ambientlightcoupledinthe
25、specimenintheremovablelightproofelement P c = ambientlightcoupledinthespecimenoncethelightproofelementhasbeenremoved 5.2 Finalmeasurementsandrequirements Calculatetheexternallightcouplingcoefficientperunitlengthwiththehelpofthefollowingequation: Couplingcoefficient(dB/m) = 0 f c log 10 P P P L - - N
26、OTE Thiscalculationassumesthatvalues P0and P1areequal.BS EN 3745-305:2002 BSI 389 Chiswick High Road London W4 4AL BSI British Standards Institution BSI is the independent national body responsible for preparing British Standards. It presents the UK view on standards in Europe and at the internation
27、al level. It is incorporated by Royal Charter. Revisions British Standards are updated by amendment or revision. Users of British Standards should make sure that they possess the latest amendments or editions. It is the constant aim of BSI to improve the quality of our products and services. We woul
28、d be grateful if anyone finding an inaccuracy or ambiguity while using this British Standard would inform the Secretary of the technical committee responsible, the identity of which can be found on the inside front cover. Tel: +44 (0)20 8996 9000. Fax: +44 (0)20 8996 7400. BSI offers members an indi
29、vidual updating service called PLUS which ensures that subscribers automatically receive the latest editions of standards. Buying standards Orders for all BSI, international and foreign standards publications should be addressed to Customer Services. Tel: +44 (0)20 8996 9001. Fax: +44 (0)20 8996 700
30、1. Email: ordersbsi-. Standards are also available from the BSI website at http:/www.bsi-. In response to orders for international standards, it is BSI policy to supply the BSI implementation of those that have been published as British Standards, unless otherwise requested. Information on standards
31、 BSI provides a wide range of information on national, European and international standards through its Library and its Technical Help to Exporters Service. Various BSI electronic information services are also available which give details on all its products and services. Contact the Information Cen
32、tre. Tel: +44 (0)20 8996 7111. Fax: +44 (0)20 8996 7048. Email: infobsi-. Subscribing members of BSI are kept up to date with standards developments and receive substantial discounts on the purchase price of standards. For details of these and other benefits contact Membership Administration. Tel: +
33、44 (0)20 8996 7002. Fax: +44 (0)20 8996 7001. Email: membershipbsi-. Information regarding online access to British Standards via British Standards Online can be found at http:/www.bsi- Further information about BSI is available on the BSI website at http:/www.bsi-. Copyright Copyright subsists in a
34、ll BSI publications. BSI also holds the copyright, in the UK, of the publications of the international standardization bodies. 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 e
35、lectronic, photocopying, recording or otherwise without prior written permission from BSI. This does not preclude the free use, in the course of implementing the standard, of necessary details such as symbols, and size, type or grade designations. If these details are to be used for any other purpose than implementation then the prior written permission of BSI must be obtained. Details and advice can be obtained from the Copyright & Licensing Manager. Tel: +44 (0)20 8996 7070. Fax: +44 (0)20 8996 7553. Email: copyrightbsi-.
