1、BSI Standards PublicationBS EN 3745-410:2015Aerospace series Fibres andcables, optical, aircraft use Test methodsPart 410: Thermal lifeBS EN 3745-410:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 3745-410:2015.It supersedes BS EN 3745-410:2007 which is wi
2、thdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee ACE/6, Aerospace avionic electrical and fibre optictechnology.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the nece
3、ssaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2015. Published by BSI StandardsLimited 2015ISBN 978 0 580 88562 4ICS 49.060Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was pub
4、lished under the authority of theStandards Policy and Strategy Committee on 31 July 2015.Amendments issued since publicationDate Text affectedBS EN 3745-410:2015EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 3745-410 July 2015 ICS 49.090 Supersedes EN 3745-410:2007English Version Aerospace ser
5、ies - Fibres and cables, optical, aircraft use - Test methods - Part 410: Thermal life Srie arospatiale - Fibre et cbles optiques usage aronautique - Mthodes dessais - Partie 410 : Dure de vie en temprature Luft- und Raumfahrt - Faseroptische Leitungen fr Luftfahrezuge - Prfverfahren - Teil 410: Leb
6、ensdauer unter Temperatureinwirkung This European Standard was approved by CEN on 14 February 2015. CEN 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-
7、to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by transl
8、ation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland
9、, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION
10、COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 3745-410:2015 EBS EN 3745-410:2015EN 3745-410:2015
11、(E) 2 Contents Page Foreword 3 1 Scope 4 2 Normative references 4 3 Test specimens 4 3.1 Fibre ends .4 4 Method A (without mechanical stress applied) 4 4.1 Preparation of test specimens .4 4.2 Test conditions 5 4.3 Apparatus .5 4.4 Procedure .5 4.4.1 Initial measurements .5 4.4.2 Test 5 4.4.3 Final
12、measurements and requirement .6 4.4.4 Special precautions .6 5 Method B (with mechanical stress applied) 6 5.1 Preparation of test specimens .6 5.2 Test conditions 6 5.3 Information to be included in the product standard 6 5.4 Apparatus .7 5.5 Procedure .8 5.5.1 Initial measurements .8 5.5.2 Test 8
13、5.5.3 Calculation of the regression line 9 5.5.4 Special precautions 10 6 Requirements 10 BS EN 3745-410:2015EN 3745-410:2015 (E) 3 European foreword This document (EN 3745-410:2015) has been prepared by the Aerospace and Defence Industries Association of Europe - Standardization (ASD-STAN). After e
14、nquiries and votes carried out in accordance with the rules of this Association, this Standard has received the approval of the National Associations and the Official Services of the member countries of ASD, prior to its presentation to CEN. This European Standard shall be given the status of a nati
15、onal standard, either by publication of an identical text or by endorsement, at the latest by January 2016 and conflicting national standards shall be withdrawn at the latest by January 2016. Attention is drawn to the possibility that some of the elements of this document may be the subject of paten
16、t rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 3745-410:2007. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European
17、 Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Sloveni
18、a, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 3745-410:2015EN 3745-410:2015 (E) 4 1 Scope This European Standard specifies a method of measuring the thermal endurance of a finished optical cable. There are two test methods incorporated which estimate the cables thermal life wit
19、h or without the mechanical stress. Method A without mechanical stress (temperature only), Method B combined temperature and mechanical stress. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application.
20、For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 2591-100, Aerospace series Elements of electrical and optical connection Test methods Part 100: General EN 3745-100, Aerospace series Fib
21、res and cables, optical, aircraft use Test methods Part 100: General EN 3745-301, Aerospace series Fibres and cables, optical, aircraft use Test methods Part 301: Attenuation ASTM-D3032, Standard test methods for hookup wire insulation1) 3 Test specimens 3.1 Fibre ends The fibre ends shall be prepar
22、ed in accordance with EN 2591-100. If not yet at standard test conditions, the specimens shall be subjected to standard test conditions and stabilized at these conditions for 24 h as defined in EN 3745-100. 4 Method A (without mechanical stress applied) 4.1 Preparation of test specimens Specimens ha
23、ve to be fixed on an apparatus representative of aircraft installation. Ten specimens are fixed on apparatus and constitute a set for life testing at each temperature. A minimum of four sets of specimens is necessary. 1) Published by: ASTM National (US) American Society for Testing and Materials (ht
24、tp:/www.astm.org/). BS EN 3745-410:2015EN 3745-410:2015 (E) 5 4.2 Test conditions The following details shall be specified if not already included in the product standard: Type of fibre/cable from which the specimens were taken, Type/number/pitch of clamps Minimum authorized long term bend radius Le
25、ngth of specimens if not 10 m Maximum permissible variation in attenuation if not 3 dB Temperature values (1 2 3 4) 4.3 Apparatus The apparatus shall comprise: A Light Launch System (LLS) as defined in EN 2591-100, A split coupler 1 10, A Light Detection System (LDS) as defined in EN 2591-100, with
26、10 channel recorder, A fixture to secure the specimens, A climatic chamber capable of temperature control of 2 C. 4.4 Procedure 4.4.1 Initial measurements If the value of the highest temperature value is not specified in the product standard make a quick estimation of the highest test temperature wi
27、th one specimen during 24 h at 80 C above the nominal rating temperature. The variation in attenuation shall not exceed the specified value. 4.4.2 Test The attenuation shall be monitored throughout the test in accordance with EN 3745-301, method C. Connect the specimen ends to the coupler, the coupl
28、er to LLS and the other specimen ends to LDS. Place the fixture in the test chamber. The coupler and connectors shall not be into climatic chamber. Begin the test sequence with the highest test temperature (1) since exposure times will be relatively short. Record the exposure time to failure for eac
29、h specimen. A failure is defined when the variation in attenuation is higher than the specified value. Stop the test sequence when all specimens in group have failed. Calculate the log average life as defined in ASTM-D3032. If the log average life at this temperature (highest) is found to be less th
30、an 100 h, too high a test temperature has been selected and these data should be discarded. Tests should be repeated at lower temperature. BS EN 3745-410:2015EN 3745-410:2015 (E) 6 Repeat this procedure with the group N 2 of specimens for 2 temperature value. Calculate the log average life as define
31、d in ASTM-D3032. Repeat this procedure with the group N 3 of specimens for 3 temperature value. Calculate the log average life as defined in ASTM-D3032. Repeat this procedure with the last group of specimens for 4 temperature value (lowest). Calculate the log average life as defined in ASTM-D3032. I
32、f the average life found at this test temperature is less than 5 000 h, this test will be made at lower temperature. 4.4.3 Final measurements and requirement The calculation of average life and extrapolation are defined in the ASTM-D3032 Standard test methods for hookup wire insulation. 4.4.4 Specia
33、l precautions Extrapolation to a temperature index expected at the selected end of life (10 000 h, 20 000 h or 40 000 h) should not exceed 25 C below the lowest aging test temperature. The log average life at the highest test temperature (1) shall not be less than 100 h. The log average life at the
34、lowest test temperature (4) shall not be less than 5 000 h. 5 Method B (with mechanical stress applied) 5.1 Preparation of test specimens One set for life testing shall consist of ten specimens fixed on the apparatus (Figure 1) at each temperature. A minimum of four sets of specimens is necessary. I
35、n order to reduce the variation of stress to the fibre the cable shall be attached to the test fixture by trapping it between two padded plates rather than using standard aircraft cable clamps. 5.2 Test conditions Length of specimens 5 m. Length of specimens within the test chamber 3 m. Maximum perm
36、issible variation in attenuation if not 3 dB at 20 C 3 C and at 850 nm. Launch conditions to be 85/85. 5.3 Information to be included in the product standard Type of fibre/cable from which the specimens were taken, Minimum long term bend radius (R), wave length if not 850 nm, Maximum permissible var
37、iation in attenuation if not 3 dB, Launch conditions if not 85/85. BS EN 3745-410:2015EN 3745-410:2015 (E) 7 5.4 Apparatus The apparatus shall comprise: A Light Launch System (LLS) as defined in EN 2591-100, A Light Detection System (LDS) as defined in EN 2591-100, A device allowing to connect the L
38、LS to all specimen shall be used to focus the test on the ageing of cable, A device allowing measuring one of the specimens or all cable without disconnection shall be used in order to keep the baseline of initial measurement. A test fixture is used to secure the specimens, this fixture shall be so
39、designed that the cable is mounted so that it can be bent at 90 either side of its centre line and is free to freely follow a curve between the two clamp points that corresponds to it minimum bend radius (D = 2R). The test sample is to be so arranged that only the portion of the sample in the flexin
40、g area is stressed during the test. The fixtures corner is to be rounded and padded see Figure 1 and Figure 2. A climatic chamber capable of temperature control of 2 C. Key 1 To the LLS 2 To the LDS 3 Fixed plate 4 Moving plate D = is twice the cable minimum bend radius R = not less than the minimum
41、 bend radius least Figure 1 Test Fixture BS EN 3745-410:2015EN 3745-410:2015 (E) 8 Key 1 Plate 2 Cable 3 Silicon rubber foam Figure 2 Fixture radius and padded edges 5.5 Procedure 5.5.1 Initial measurements If the highest test temperature value is not specified in the product standard make an evalua
42、tion of the highest test temperature with one specimen during 24 h at 80 C above the nominal rating temperature. This evaluation needs to be done at temperatures below the degradation temperature of raw materials used in the cable under test. The jacket shall not fail or the variation in attenuation
43、 shall not exceed the specified value in which case repeat the test at a lower temperature. 5.5.2 Test The attenuation shall be measured at the end of each exposure cycle in accordance with EN 3745-301, method C. Connect the specimen ends to the LLS and the other specimen ends to LDS during all the
44、cycles. Place the fixture in the test chamber. The connectors shall not be in the climatic chamber. Measure the attenuation of each test specimen. Begin the test sequence with the highest test temperature (1) since exposure times will be relatively short. Expose the specimens for the first test cycl
45、e. NOTE This measurement is for reference only and does not form part of the qualification testing. To monitor the behaviour of the cable/s under test at high temperature, an attenuation measurement of each cable shall be made at the maximum point of the high temperature cycle immediately prior to r
46、educing the temperature to ambient. On completion of the exposure period allow the specimen to return to ambient. Bend the specimen to 90oonce in each direction then return the specimen to the neutral position before measuring the attenuation value. Inspect the cable jacket in the bend area for majo
47、r cracks or splits without disturbing the cable. BS EN 3745-410:2015EN 3745-410:2015 (E) 9 Start the next exposure cycle. Record the number of exposure cycles to failure for each specimen. A failure is defined when the variation in attenuation is higher than the specified value or the jacket splits
48、or cracks. The life of each specimen is defined as the number of cycles to failure times the length of each cycle. Stop the test sequence when all specimens in the set have failed. Calculate the log average life as defined in ASTM-D3032. If the log average life at this temperature (highest) is found
49、 to be less than 100 h, too high a test temperature has been selected and these data should be discarded. Tests should be repeated at lower temperature. Repeat this procedure with the group N 2 of specimens for 2 temperature value. Calculate the log average life as defined in ASTM-D3032. Repeat this procedure with the group N 3 of specimens for 3 temperature value. Calculate the log average life as defined in ASTM-D3032. If the calculated regression line does
