1、ASD STANDARD NORME ASD ASD NORM prEN 3475-809 Edition P 1 July 2007 PUBLISHED BY THE AEROSPACE AND DEFENCE INDUSTRIES ASSOCIATION OF EUROPE - STANDARDIZATION Avenue de Tervuren, 270 - B-1150 Brussels - Tel. + 32 2 775 8126 - Fax. + 32 2 763 3565 - www.asd-stan.orgICS: 49.060 Descriptors: ENGLISH VER
2、SION Aerospace series Cables, electrical, aircraft use Test methods Part 809: Resistance unbalance Srie arospatiale Cbles lectriques usage aronautique Mthodes dessais Partie 809 : Dsquilibre de rsistance Luft- und Raumfahrt Elektrische Leitungen fr Luftfahrtverwendung Prfverfahren Teil 809: Widersta
3、ndsunsymmetrie 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
4、of 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 us
5、ers 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
6、the status of a national standard and by withdrawing any national standards conflicting with the EN. Edition approved for publication 31 July 2007 Comments should be sent within six months after the date of publication to ASD-STAN Electrical Domain Copyright 2007 by ASD-STAN Copyright European Assoc
7、iation of Aerospace Industries Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-prEN 3475-809:20072 Contents Page Foreword2 1 Scope 3 2 Normative references 3 3 Preparation of specimens.3 4 Apparatus .3 5 Method 3 6 Requireme
8、nt.3 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 approval for Publication. Copyright Euro
9、pean Association of Aerospace Industries Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-prEN 3475-809:20073 1 Scope This standard specifies methods for measuring resistance unbalance for digital data transmission cable. It
10、shall be used together with EN 3475-100. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendm
11、ents) applies. EN 3475-100, Aerospace series Cables, electrical, aircraft use Test methods Part 100: General. EN 3475-301, Aerospace series Cables, electrical, aircraft use Test methods Part 301: Ohmic resistance per unit length. 3 Preparation of specimens The measurements may be performed on produc
12、tion drums and/or on the final delivery package. 4 Apparatus Wheatstone bridges, automatic or semi-automatic equipment may also be used with an accuracy of 0,5 %. 5 Method The conductor resistance unbalance is usually determined at the same time that conductor resistance measurements are made (EN 34
13、75-301). The resistance measure of each conductor of any pair shall be performed at or corrected to 20 C temperature. The temperature correction shall be performed as described in test method EN 3475-301. After measurement, the resistance unbalance calculation is: 100baba1+=RRRRDR 100dcdc2+=RRRRDR w
14、here Ra, Rbare the resistance of each conductor of the pair 1; and Rc, Rdare the resistance of each conductor of the pair 2 (in case of quad cable). Used expression for DR1and DR2are percent resistance unbalance. 6 Requirement The resistance unbalance obtained shall not exceed the values specified in the product standard. Copyright European Association of Aerospace Industries Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-
