AECMA PREN 3745-705-2006 Aerospace series Fibres and cables optical aircraft use Test methods Part 705 Contrast measurement Edition P 1《航空航空航天系列 　航空用光缆和光纤　试验方法.第705部分 对比测量》.pdf

1、ASD STANDARD NORME ASD ASD NORM prEN 3745-705 Edition P 1 September 2006 PUBLISHED BY THE AEROSPACE AND DEFENCE INDUSTRIES ASSOCIATION OF EUROPE - STANDARDIZATION Gulledelle 94 - B-1200 Brussels - Tel. + 32 2 775 8126 - Fax. + 32 2 763 3565 - www.asd-stan.org ICS: 49.060 Descriptors: ENGLISH VERSION

2、 Aerospace series Fibres and cables, optical, aircraft use Test methods Part 705: Contrast measurement Srie arospatiale Fibres et cbles optiques usage aronautique Mthodes dessais Partie 705 : Mesure de contraste Luft- und Raumfahrt Faseroptische Leitungen fr Luftfahrzeuge Prfverfahren Teil 705: Kont

3、rastmessung This “Aerospace Series“ Prestandard has been drawn up under the responsibility of ASD-STAN (The AeroSpace and Defence Industries Association of Europe - Standardization). It is published for the needs of the European Aerospace Industry. It has been technically approved by the experts of

4、the concerned Domain following member comments. Subsequent to the publication of this Prestandard, the technical content shall not be changed to an extent that interchangeability is affected, physically or functionally, without re-identification of the standard. After examination and review by users

5、 and formal agreement of ASD-STAN, it will be submitted as a draft European Standard (prEN) to CEN (European Committee for Standardization) for formal vote and transformation to full European Standard (EN). The CEN national members have then to implement the EN at national level by giving the EN the

6、 status of a national standard and by withdrawing any national standards conflicting with the EN. Edition approved for publication 30 September 2006 Comments should be sent within six months after the date of publication to ASD-STAN Electrical Domain Copyright 2006 by ASD-STAN Copyright Association

7、Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-prEN 3745-705:20062 Contents Page Foreword . 2 1 Scope 3 2 Normative references 3 3 Terms and definitions. 3 4 Preparation o

8、f samples. 3 5 Test equipment 4 6 Process. 5 Foreword This standard was reviewed by the Domain Technical Coordinator of ASD-STANs Electrical Domain. After inquiries and votes carried out in accordance with the rules of ASD-STAN defined in ASD-STANs General Process Manual, this standard has received

9、approval for Publication. Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-prEN 3745-705:20063 1 Scope This standard specifies the process to be applie

10、d for measuring different colour densities of cable identification markings. It is designed to define a reproducible process of contrast value determination. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only t

11、he edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 7724-1, Paints and varnishes Colorimetry Part 1: Principles. CIE 15, Colorimetry. 1) 3 Terms and definitions For the purposes of this document, the following terms

12、and definitions apply. 3.1 contrast ratio of reflecting light (here: reflecting light of cable identification marking and cable surface) 3.2 illuminance reflection of visible light 3.3 measuring range maximum effective range of measurement 4 Preparation of samples The cable samples shall be identifi

13、ed in compliance with applicable manufacturing instruction using the power density specified in the technical specification. The surfaces of the cable samples shall be clean and without damage. The identification markings to be measured shall even be in colour and shall have sharply defined marking

14、edges i.e. marks are correctly focussed. Before starting measurements clean the surfaces with a soft, lint-free cloth to avoid distortion of test results by a roughened surface or “deposits“. 1) Published by CIE Central Bureau - Kegelgasse 27 - A-1030 Wien - Austria Copyright Association Europeene d

15、es Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-prEN 3745-705:20064 5 Test equipment 5.1 Components of the measuring device The measuring device comprises a photometer, lighting equip

16、ment and a cable handling device. The whole set-up shall be designed to ensure that test results are not falsified by external influences. The photometer installation shall be stable and free from vibrations, and influences by external light and reflections from scattered light shall be excluded. 5.

17、2 Equipment colour The device for handling cable samples and accessories shall be designed in matt black colour to absorb scattered light. 5.3 Illuminance Illuminance shall be determined with a calibrated electrical photometer. The manufacturer instructions concerning the measuring probe work range

18、and operating instructions shall be observed. Measuring sensitivity of the photometer shall be in conformity with CIE-publication 15. 5.4 Diameter of measuring spot The admissible diameter of the measuring spot shall not exceed 75 % of the marking size (X and Y dimension). Measuring tolerance of the

19、 photometer shall be diameter of measuring spot). The contrast is calculated as follows: K = %100max.min.max. LLL )( where K is the contrast L is the light intensity 6.5 Requirement The contrast value as determined between cable identification marking and cable surface shall conform to the specifications of the corresponding product standard. Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-