1、BRITISH STANDARD AEROSPACE SERIES BS G235:1987 Specification for Electric cables for general airframe or equipment interconnect use(150 C), wrapped insulation with silver plated conductors UDC 629.7.064.5:621.315.33-408.4BSG235:1987 This BritishStandard, having been prepared under the directionof th
2、e Aerospace Standards Committee, was published under the authority ofthe Board of BSI and comesintoeffect on 30September1987 BSI01-2000 The following BSI references relate to the work on this standard: Committee reference ACE/6 Draft for comment85/71992 DC ISBN 0 580 15921 3 Committees responsible f
3、or this BritishStandard The preparation of this BritishStandard was entrusted by the Aerospace Standards Committee (ACE/-) to Technical Committee ACE/6, upon which the following bodies were represented: BEAMA Ltd. British Airways British Rubber Manufacturers Association Civil Aviation Authority Elec
4、tric Cable Makers Confederation Electronic Components Industry Federation Ministry of Defence National Supervising Inspectorate Society of British Aerospace Companies Limited Amendments issued since publication Amd. No. Date of issue CommentsBSG235:1987 BSI 01-2000 i Contents Page Committees respons
5、ible Inside front cover Foreword ii 1 Scope 1 2 Classification 1 3 Construction 1 4 Designation and marking 2 5 Packaging and labelling 2 6 Tests 2 7 Reference samples 6 Figure 1 Variation of resistance of copper with temperature 16 Table 1 Type01, class1: single-core unscreened interconnect cables(
6、150 C) 6 Table 2 Type02, class1: single-core unscreened airframe cables(150 C) 7 Table 3 Type01, classes2,3 and4: multi-core unscreened, twisted interconnect cables without jacket(150 C) 7 Table 4 Type02, classes2,3 and4: multi-core unscreened, twisted airframe cables without jacket(150 C) 8 Table 5
7、 Type03, classes2,3 and4: multi-core unscreened, twisted interconnect cables with jacket(150 C) 8 Table 6 Type04, classes2,3 and4: multi-core unscreened, twisted airframe cables with jacket(150 C) 8 Table 7 Type05, classes1,2,3 and4: single-core screened with jacket, and multi-core twisted and scree
8、ned with jacket, interconnect cables(150 C) 9 Table 8 Type06, classes1,2,3 and4: single-core screened with jacket, and multi-core twisted and screened with jacket, airframe cables(150 C) 10 Table 9 Test application 11 Table 10 Specific test parameters 13 Table 11 Current ratings in amperes for gener
9、al purpose150 C airframe cable 15 Publications referred to Inside back coverBSG235:1987 ii BSI 01-2000 Foreword This BritishStandard, having been prepared under the direction of the Aerospace Standards Committee, specifies requirements for a range of lightweight thin-wall insulated cables that are i
10、ndividually suitable for general airframe or equipment interconnect use. The dielectric insulation material is spirally lapped with an overall coating to provide the necessary colour coding and to provide a base for printed identification legends. The standard requires the application of the dielect
11、ric material so as to provide the minimum penalties of weight and space whilst offering reliable performance over a full airframe life of not less than50000h. Cables manufactured to this standard are not required to meet the fire resistance requirements of BS3G100:Subsection 3.13 but they are requir
12、ed to satisfy the flammability requirements of BS G230. Attention is drawn to BS G230 which specifies the general requirements for aircraft electric cables (second series). A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are respo
13、nsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1 to16, an inside back cover and a back cover. This standard has been
14、updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BSG235:1987 BSI 01-2000 1 1 Scope This BritishStandard specifies construction and performance requirements for a range of lightweight cables with wrapped ins
15、ulation and silver plated conductors suitable for general airframe use in the size range26 to0000, and for equipment interconnect in the size range26 to18. The following types of cable are specified: The cables are suitable for continuous use where the maximum stabilized conductor temperature does n
16、ot exceed150 C. They are suitable for applications involving flexing at temperatures down to65 C. The cables are suitable for use where the potential between conductors or between a conductor and screen, or the aircraft structure does not exceed600V r.m.s. and the frequency does not exceed2000Hz. In
17、terconnect cables are suitable for use in areas with some physical protection, such as behind panels or bulkheads, They also have an application for the internal wiring of equipment. Airframe cables are of sufficiently robust construction to be used for open aircraft wiring. The short-term and long
18、term current ratings for the cables are specified in this standard. NOTEThe titles of the publications referred to in this standard are listed on the inside back cover. 2 Classification Cables are classified according to the number of cores as follows: 3 Construction 3.1 General The materials and me
19、thod of construction used for the formation of the cables shall be defined and controlled to the satisfaction of the Approving Authority 1) . No change shall be made to such materials or processes unless it can be shown to the satisfaction of the Approving Authority that the performance and handling
20、 properties of the cable have not been degraded. The cable shall be made of materials such that the performance requirements of this standard are satisfied. 3.2 Conductors 3.2.1 Conductors shall comply with BS G231 before fabricating into completed cables. 3.2.2 Copper strands and copper alloy stran
21、ds shall be silver plated. 3.3 Insulation The insulation for interconnect cables shall consist of one or more overlapped tapes of insulating material, and for airframe cables, two or more overlapped tapes. An overall coating may also be provided which, for the purposes of this standard, shall be reg
22、arded as part of the cable. The insulating material shall be such that the performance requirements of this standard are satisfied. Only100% new materials that have been through only those processes essential to their manufacture and application shall be used. Type01 interconnect Single-core or twis
23、ted multi-cores only Type02 airframe Type03 interconnect Two or more cores, with anouter jacket Type04 airframe Type05 interconnect Single- or multi-core, with a screen and outer jacket Type06 airframe class1: single core class2: two core class3: three core class4: four core 1) The Approving Authori
24、ty is either: a) for UK Civil Aviation products, the Civil Aviation Authority (or their accredited representatives); or b) for UK military products, information is available from the Procurement Executive, Ministry of Defence, Directorate General of Defence Quality Assurance, Directorate of Standard
25、ization, Kentigern House,65 Brown Street, Glasgow G28EX. BSG235:1987 2 BSI 01-2000 3.4 Screen The screen shall be constructed of a braid having a coverage of85% minimum, and a lay factor less than3 when calculated in accordance with Appendix A of BS G230. There shall be no joints in the complete scr
26、een. Where breaks in individual strands occur, the ends shall be brazed or tucked into the weave ensuring that the cut end is on the outside of the screen. There shall be not more than one such break in any300mm length of cable or in any10m length of individual strand. Strands from which the braid i
27、s constructed shall be silver plated and comply with BS G231 before braiding. 3.5 Jacket The jacket shall be made of insulating material, and shall be constructed, such that the performance requirements of this standard are satisfied. 3.6 Single-core cables The mass and dimensions of single-core cab
28、les shall be as given in Table 1 and Table 2 as appropriate. 3.7 Multi-core cables The mass and dimensions of multi-core cables shall be as given in Table 3 to Table 8 as appropriate. The cables shall consist of two or more single cores complying with3.6, twisted together with a lay of approximately
29、12times the pitch circle diameter for sizes26 to4 and approximately16 times the pitch circle diameter for sizes2 to0000. Types01 and02 shall consist of twisted assemblies of single-core cable, types03 and04 of twisted assemblies with an outer jacket, and types05 and06 of twisted assemblies with a sc
30、reen and outer jacket. 3.8 Colour The colour of the insulation for class1 cables, the core insulation for multi-core cables and the jackets shall comply with BS G230. 4 Designation and marking 4.1 Manufacturers marking and designation The designation and marking of the cables shall be in accordance
31、with BS G230. 4.2 User applied marking 4.2.1 The surface of the insulation or coating of type02 (airframe) cable shall be suitable for the acceptance of user applied identification marks by at least one of the following methods: a) hot stamp marking; b) laser marking; c) ink jet. The cable manufactu
32、rer shall declare which method is suitable and the tests given in clause6 shall be performed using cables that have been so marked. 4.2.2 Appropriate methods of marking the outer jacket of cable types03,04,05 and06 shall be declared by the manufacturer who may specifically prohibit the use of hot st
33、amp or laser marking. 4.2.3 Type01 (interconnect) cable shall not be required to accept hot stamp or laser markings or any other method that may degrade the insulation material. 5 Packaging and labelling The cables shall be packaged and labelled in accordance with BS G230. 6 Tests The following test
34、s shall be carried out in accordance with BS G230. Specific requirements of this standard are given against the appropriate test. The application of each test for qualification approval, production quality testing, inspection lot testing and production routine testing shall be as given in Table 9. A
35、ll qualification approval test specimens shall be marked in accordance with clause4 before commencement of testing.BSG235:1987 BSI 01-2000 3 NOTEFor qualification approval testing, specimens selected from a particular size within the following groups may be considered as proving the requirements for
36、 all sizes within that group of a given type (see clause1). Qualification of type05 cable may be considered as proving the requirements of type03, classes2 to4, and type06 as proving type04, classes2 to4. Group1. Sizes26 to24, type02, classes1 to4 Group2. Sizes22 to16, type02, classes1 to4 Group3. S
37、izes14 to10, type02, class1 Group4. Sizes8 to2, type02, class1 Group5. Sizes1 to0000, type02, class1 Group6. Sizes26 to24, type01, classes1 to4 Group7. Sizes22 to18, type01, classes1 to4 Group8. Sizes26 to16, type06, classes1 to4 Group9. Sizes26 to18, type05, classes1 to4 BS G230 test no. Test appli
38、cable to cable types01 and02 Specific requirements of this standard 1. 2. 3. 4. 5. 6. 7. Appearance and identification of finished cable Mass per unit length of finished cable Conductor composition Visual examination of strands Insulation thickness and concentricity Core and cable outer diameters Te
39、nsile strength and elongation at break of copper or copper alloy conductors Maximum values shall be as given in Table 1 to Table 6 Minimum values shall be as given in Table 1 and Table 2 Minimum and maximum values shall be as given in Table 1 to Table 6 Values shall be as follows: Strand diameter Te
40、nsile strength Elongation Min. Max. Min. mm Copper alloy 0.08 to0.12 N/mm 2 350 (for7 strands) N/mm 2 % 6 Copper 0.08 to0.12 0.15 to0.45 220 220 300 300 9 10 9. 10. 11. 12. 14. 14(a). 14(b). 15. 16. 16(a). 16(b). a 16(c). a Strand plating continuity Strand plating adherence Strand plating thickness
41、Electrical resistance of conductor Solderability Method1 Method2 Conductor strand adhesion High voltage Immersion Dry spark Dry impulse Maximum values shall be as given in Table 1 to Table 6 This test shall be carried out on sizes20 to26 only. Usenon-activated flux complying with4.6.2 of BS2011-2.1T
42、:1981 and solder of grade KP of BS219. Solder bath temperature235 3 C. Wetting time1.0s 2500 75V r.m.s. 5000 150V r.m.s. 8000 250V peak a Either test16(b) or16(c) may be carried out.BSG235:1987 4 BSI 01-2000 BS G230 test no. Test applicable to cable types01 and02 Specific requirements of this standa
43、rd 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 28(a). 28(b). 29. 30. 31. 32. 35. Insulation resistance Surface resistance Accelerated ageing Thermal endurance Adherence of insulation on conductor Delamination and shrinkage Delamination and insulation blocking Room temperature bend Cold bend Dyna
44、mic cut-through Notch propagation resistance Flammability Method1 Method2 Resistance to fluids Scrape abrasion Overload resistance Delamination Climatic Test temperature200 2 C. Time168h. Mandrel diameter and force shall be as given in Table 10 50000h minimum at150 2 C Minimum adherence forces shall
45、 be as given in Table 10 Five cycles from room temperature to150 2 C holding the top temperature for1h and allowing the cable to return to room temperature between cycles. Maximum length of conductor exposed at each end is1.0mm for sizes26 to10, and one-quarter maximum outside diameter for sizes8 to
46、0000 Mandrel diameter and tension shall be as given in Table 10. Test temperature150 2 C. Time100h Mandrel diameter and tension shall be as given in Table 10 Mandrel diameter and tension shall be as given in Table 10. Test temperature65 2 C. Time6h Test temperature150 2 C,6000g/min 10% at the sample
47、. Minimum force to cut-through shall be as given in Table 10 Five specimens,15s exposure to flame Five specimens,15s exposure to flame Test temperature150 2 C. Force and cycles shall be as given in Table 10 T 1 =250 5 C T 2 =400 10 C Ageing temperature T 2 =250 5 C Test temperature T 1 =150 3 C Forc
48、e shall be as given in Table 10 Humidity. Carry out the test in accordance with clause2 c) of BS G229 a . Category A for type01 and category B for type02. Prepare the specimens by winding at least six turns on a mandrel of the diameter specified for test23 in Table 10. On removal from the chamber un
49、wind the cable from the mandrel. It shall show no sign to normal vision of deterioration and the identification shall remain legible. The specimen shall then be subjected to the immersion test test16(a) except that the specimen length may be reduced Fungus resistance. Carry out the test in accordance with clause2 j) of BS G229 b . Category F. There shall be no sign to normal vision of fungus growth a BS G229 refers to clause6 of EUROCAE ED-14A and RTCA DO-160A for the humidity test.
