1、ASD STANDARD NORME ASD ASD NORM prEN 3475-604 Edition P 2 June 2009 PUBLISHED BY THE AEROSPACE AND DEFENCE INDUSTRIES ASSOCIATION OF EUROPE - STANDARDIZATIONAvenue de Tervuren, 270 - B-1150 Brussels - Tel. + 32 2 775 8126 - Fax. + 32 2 775 8131 - www.asd-stan.orgICS: 49.060 Supersedes edition P 1 of
2、 October 1997 and will supersede EN 3475-604:2002 Descriptors: Aerospace industry, aircraft equipment, electrical cable, test ENGLISH VERSION Aerospace series Cables, electrical, aircraft use Test methods Part 604: Resistance to dry arc propagation Srie arospatiale Cbles lectriques usage aronautique
3、 Mthodes dessais Partie 604 : Rsistance lamorage et la propagation darc lectrique, essai sec Luft- und Raumfahrt Elektrische Leitungen fr Luftfahrtverwendung Prfverfahren Teil 604: Lichtbogenfestigkeit, trocken This “Aerospace Series“ Prestandard has been drawn up under the responsibility of ASD-STA
4、N (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 the concerned Domain following member comments. Subsequent to the publication of this Prestandard, th
5、e 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 and formal agreement of ASD-STAN, it will be submitted as a draft European Standard (prEN) to CEN (E
6、uropean 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 status of a national standard and by withdrawing any national standards conflicting with the EN. Edi
7、tion approved for publication 10 June 2009 Comments should be sent within six months after the date of publication to ASD-STAN Electrical Domain Copyright 2009 by ASD-STAN Copyright ASD-STAN Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without licens
8、e from IHS-,-,-prEN 3475-604:20092 Contents Page Foreword Erreur ! Signet non dfini. 1 Scope 3 2 Normative references 3 3 Specimen requirements 4 4 Preparation of specimen.4 5 Apparatus .5 6 Method 9 7 Requirements 11 Foreword This standard was reviewed by the Domain Technical Coordinator of ASD-STA
9、Ns 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 ASD-STAN Provided by IHS under license with AECMA Not for ResaleNo reproduction or networki
10、ng permitted without license from IHS-,-,-prEN 3475-604:20093 1 Scope This standard specifies a method for appraising the behaviour of cable insulation when an electric arc is initiated and maintained by two powered cables rubbing against a blade. This standard shall be used together with EN 3475-10
11、0. The primary aim of this test is: to produce, in a controlled fashion, continuous failure effects which are representative of those which may occur in service when a typical cable bundle is damaged by abrasion such that electrical arcing occurs, both between cables and between cables and conductiv
12、e structure, and to examine the aptitude of the insulation to track, to propagate electric arc to the electrical origin. Originally defined for 115 Vac network, this test also proposes conditions for 230 Vac network. Unless otherwise specified in product standard, only 115 Vac conditions shall be sa
13、tisfied. Six levels of prospective fault current have been specified for concerned cable sizes (see Clause 7). It is generally agreed that larger sizes need not be assessed since the short-circuit phenomenon becomes dominant at low line impedances. Unless otherwise specified in the technical/product
14、 standard sizes 002, 006 and 020 cable shall be assessed. 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 (inc
15、luding any amendments) applies. EN 2350, Aerospace series Circuit breakers Technical specification. EN 2702, Aerospace series Aluminium alloy AL-P6061 T6 or T62 Drawn or extruded bar and section a or D 200 mm. EN 3197, Aerospace series Installation of aircraft electrical and optical interconnection
16、systems.1)EN 3475-100, Aerospace series Cables, electrical, aircraft use Test methods Part 100: General. EN 3475-302, Aerospace series Cables, electrical, aircraft use Test methods Part 302: Voltage proof test. A-A-52083, Tape, lacing and tying, glass. 2)1) Published as ASD Prestandard at the date o
17、f publication of this standard. 2) Published by : Department of Defense Industrial Supply Center, ATTN: DISC-BBEE, 700 Robbins Avenue, Philadelphia, PA 19111-5096 USA. Copyright ASD-STAN Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license fr
18、om IHS-,-,-prEN 3475-604:2009 4 3 Specimen requirements Cables to be tested shall be of traceable origin and shall have passed the high voltage dielectric test defined in the product standard. 4 Preparation of specimen 4.1 Cut seven separate lengths of approximately 0,5 m consecutively from one leng
19、th of cable, and strip each of the ends of insulation to permit electrical connection. Clean each length of cable with a clean cloth moistened with propan-2-ol (isopropyl alcohol) fluid. 4.2 Lay up the seven cables as follows: a) Form the cables in a six around one configuration as shown in Figure 1
20、. b) Ensure that all cables are straight and geometrically parallel, and restrained by ties such that they are in continuous contact for at least a 75 mm continuous length around the mid point of the loom length. This is called the test zone. c) Position the ties at 15 mm to 20 mm spacing within the
21、 test zone. The tie material shall be PTFE glass lacing tape conforming to A-A-52083 type IV, finish D, size 3. d) Number the cables as shown in Figure 1 such that the cables in contact with the blade are numbers A1 and B1. Test Blade Key 1 Original position 2 Final position A1-A2 : Phase A B1-B2 :
22、Phase B C1-C2 : Phase C N1-N2 : Inactive cables connected to earth Figure 1 Specimen configuration B2 C1 A2 B1 A1 N1 N2 12Copyright ASD-STAN Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-prEN 3475-604:20095 5 Apparatus 5.1
23、 Electrical equipment Connect the seven cables of the test sample within a circuit as shown in Figure 2. This circuit shall have the following requirements: a) The provision of adjustable levels of prospective fault currents for the five A, B and C cables and an electrical return path for the two N
24、cables. b) A three phase 115/200 V 400 Hz (115 Vac network) or 230/400 V 400 Hz (230 Vac network) star (Y) connected supply shall be derived from a dedicated rotary machine capable of sustaining the maximum prospective fault current given in Table 1 for at least sufficient time for circuit protectio
25、n to operate. In any case the generator shall have a sufficient rating to provide these prospective fault currents. c) 115 Vac or 230 Vac circuit breakers shall be single pole units rated at the values specified in Table 2. They shall have trip characteristics in accordance with EN 2350 or as requir
26、ed in the product specification. NOTE 1 Reference of circuit breakers used shall be recorded. NOTE 2 In particular case, others ratings of thermal breaker protection could be employed in accordance with aircraft manufacturer rules. d) The electrical power source shall be appropriately protected and
27、it shall be established that no combination of test circuit events would activate this protection. e) The ballast resistors shall be non inductive and of appropriate power rating. Care shall be taken to position all laboratory wiring such that inductive effects are reduced to a practical minimum. Su
28、pply cables shall be as short as possible. f) Cables A, B and C shall be connected to indication and open circuit detectors at entry into the grounded star point. These components shall limit the standing current to no more than 10 % of the circuit breaker rating. g) The automatic shut down facility
29、 shall provide, upon the detection of any open circuit during test and after a 10 s delay, removal of the blade from the specimen and for electrical power to be removed. Open circuit in this case means either a physical break in the specimen or a thermal breaker trip. NOTE In the case of the automat
30、ic shut down facility is not used, the physical break in the specimen are detected by lamps in series with the rheostat Rg. h) A heavy duty electrical bonding strap shall be connected between the blade of the test rig and the electrical star point of the generator. i) Appropriate instrumentation, re
31、cording and switching control shall be installed in accordance with good laboratory practice. j) A rheostat Rg adjusting current (I) in the circuit to a value equal to 10 % of the circuit breaker current. Copyright ASD-STAN Provided by IHS under license with AECMA Not for ResaleNo reproduction or ne
32、tworking permitted without license from IHS-,-,-prEN 3475-604:20096 Figure 2 Test schematic circuit 5.2 Test equipment Construct an apparatus as shown diagrammatically in Figures 3a), 3b) and 3c) which includes the following minimum provisions: a) A lightweight, freely pivoting test fixture to hold
33、the blade at a 90 angle to the specimen and to exert a controlled force on the specimen. NOTE Generally a mounting on 50 mm centres shall hold the individual cables of the specimen in close proximity. b) Electrical terminations to provide a ready means of connecting test specimens into the circuit a
34、s shown in Figure 2. c) An aluminium blade complying with material specification T6061-T6 (EN 2702) and Figure 3c). d) A mechanism to provide a minimum oscillating stroke of 15 mm excursion at a frequency of (8 2) Hz. e) A blade carrier to give a downward force at the blade of (2,5 0,1) N. f) A mech
35、anical stop to limit the fall of the oscillating blade to within an accuracy of 0,2 mm measured at the point of contact. g) Means of separating the blade from the specimen, both manually and automatically if used. phase Aphase Bphase CSupplyprotectionRfD2Test bundle Indicators (lamp)+RgIIIIIA2A1B2B1
36、N1C1N2VUVVTest BladeCopyright ASD-STAN Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-prEN 3475-604:2009 7 h) An electrical connection of the aluminium blade to the neutral of the test power supply (see 5.1 h). i) A transpa
37、rent enclosure to protect personnel from ejected molten metal and short wavelength ultra violet light. 3 45 2 1 Key 1 Blade carrier guide 2 Aluminium blade 3 Bundle 4 Heat insulation (e.g.: PTFE) 5 Aluminium support Figure 3a) Copyright ASD-STAN Provided by IHS under license with AECMA Not for Resal
38、eNo reproduction or networking permitted without license from IHS-,-,-prEN 3475-604:20098 23 65 7 43 1Key 1 Blade 2 Bundle 3 Stop 4 Cable tie 5 Spring 6 Contact pressure adjustement 7 Depth adjustement shim Figure 3b) Copyright ASD-STAN Provided by IHS under license with AECMA Not for ResaleNo repro
39、duction or networking permitted without license from IHS-,-,-prEN 3475-604:2009 9 2 1Key 1 Sharpen edge with 60 grit aluminium disc sander directed “towards the blade“ (i.e. to avoid feathered edge) 2 Aluminium square (10 mm) Figure 3c) 5.3 Test protocol 5.3.1 The procedure embraces copper cable siz
40、es 001 to 050 (26 to 10) or aluminium cable sizes 002 to 090 (24 to 8), and for each cable size six values of prospective fault current have been defined. Performance of a cable size at a given fault intensity shall be determined by testing three samples. Thus 18 samples are required for every cable
41、 size. 5.3.2 For the purposes of cable qualification at least sizes 002, 006 and 020 shall be tested. Additional testing of other sizes may be deemed necessary in particular cases and values of prospective fault currents, the ratings of thermal breaker protection which are typical of aircraft use an
42、d the blade form to be employed have been included in this specification. 5.3.3 It is emphasized that electrical arcing tests are essentially destructive and can be hazardous to personnel. Therefore tests shall be undertaken with all observers shielded from direct physical and visual exposure as not
43、ed in 5.2 i). The use of video recording for all tests is required. 5.4 Test rig set-up 5.4.1 Install the rating of circuit breaker appropriate to the cable type and size to be tested (Table 2). Fit a blade to the reciprocating head of the test rig of the appropriate type shown in Figures 3a) and 3b
44、). 5.4.2 Heavy duty electrical shorting connections shall be fitted in substitution of a test sample to enable prospective fault currents to be set by adjustment of resistances Rf. Because these currents would trip the thermal breakers very rapidly these shall be shunted to permit the pulsing of cur
45、rent until the desired value is obtained. Re-instate the thermal protection. 5.4.3 With electrical power removed adjust the test apparatus to give the correct conditions of blade stroke, frequency and downwards force. Ensure that the test fixture is correctly positioned and that the method of holdin
46、g the specimen provides satisfactory restraint. 5.4.4 Modify a verification sample by removing a section of cables A1 and B1 in the test zone. Adjust the blade depth stop such that the final blade position is at least half the conductor diameter of A1 or B1, from wires A2, B2 and C1, as shown by Fig
47、ure 1. 6 Method 6.1 Test procedure 6.1.1 Install a test specimen with electrical connections as shown in Figure 1 and with Rf set, as in 5.4.2 above, to give the required current from Table 1. Copyright ASD-STAN Provided by IHS under license with AECMA Not for ResaleNo reproduction or networking per
48、mitted without license from IHS-,-,-prEN 3475-604:200910 6.1.2 Apply electrical power to the specimen and gently make contact with the blade. Arm the automatic blade lifting circuit, if used, and start the abrading action. NOTE 1 Only blades in good condition shall be used on new samples. If the abrading edge of a blade becomes significantly degraded after a circuit breaker trip at any stage it shall be replaced. NOTE 2 Before each test series check that thermal breakers are operating within their specified trip limits when subjected to 100 % overload. NOTE 3 Sha
