1、Designation: F2799 09Standard Practice forMaintenance of Airplane Electrical Wiring Systems1This standard is issued under the fixed designation F2799; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A num
2、ber in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 DefinitionThis practice defines acceptable practicesand processes for the maintenance, preventative maintenance,and repair of electric sys
3、tems in general aviation aircraft. Thispractice does not change or create any additional regulatoryrequirements nor does it authorize changes in or permitdeviations from existing regulatory requirements.1.2 ApplicabilityThe guidance provided in this practice isdirected to air carriers, air operators
4、, maintenance providers,repair stations, and anyone performing maintenance or repairs.1.3 Protections and WarningsThis practice provides guid-ance to minimize contamination and accidental damage toelectrical wiring interconnection systems (EWIS) while work-ing on aircraft.1.4 “Protect and Clean As Y
5、ou Go” PhilosophyThisphilosophy is applied to aircraft wiring through inclusion inoperatorsmaintenance and training programs. This philosophystresses the importance of protective measures when workingon or around wire bundles and connectors. It stresses howimportant it is to protect EWIS during stru
6、ctural repairs, (STC)installations, or other alterations by ensuring that metal shav-ings, debris, and contamination resulting from such work areremoved.1.5 UnitsThe values given in inch-pound units are to beregarded as the standard. The values given in parentheses aremathematical conversions to SI
7、units that are provided forinformation only and are not considered standard.NOTE 1When SI units are required, refer to Annex 5 of ICAO.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to est
8、ablish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2F2490 Guide for Aircraft Electrical Load and Power SourceCapacity AnalysisF2639 Practice for Design, Alteration, and Certification ofAirp
9、lane Electrical Wiring Systems2.2 ICAO Standard:ICAOAnnex 5 Units of Measurement to Be Used inAir andGround Operations32.3 JEDEC Standard:EIA 471 Symbol and Label for Electrostatic SensitiveDevices42.4 NEMA Standard:WC 27500 Standards for Aerospace and Industrial ElectricCable52.5 RTCA Standard:DO-1
10、60C Environmental Conditions and Test Proceduresfor Airborne Equipment62.6 SAE Standards:AS 4372 Performance Requirements for Wire, Electric,Insulated Copper or Copper Alloy7AS 4373 Test Methods for Insulated Electric Wire7AS 21919 Clamp, Loop Type, Cushioned Support7AS 50881 Wiring Aerospace Vehicl
11、e7ARP 1870 Aerospace Systems Electrical Bonding andGrounding for Electromagnetic Compatibility and Safety7ARP 1928 Torque Recommendations for Attaching Electri-cal Wiring Devices to Terminal Boards or Blocks, Studs,Posts, Etc.72.7 Federal Standards:Advisory Circular 20-53A Protection of Aircraft Fue
12、l Sys-tems against Fuel Vapor Ignition due to Lightning1This practice is under the jurisdiction of ASTM Committee F39 on Normal andUtility Category Airplane Electrical Wiring Systems and is the direct responsibilityof Subcommittee F39.02 on Inspection, Maintenance, and Repair.Current edition approve
13、d Nov. 1, 2009. Published December 2009. DOI:10.1520/F2799-09.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website
14、.3Available from ICAO, Customer Services Unit, 999 University St., Montreal,Quebec, H3C 5H7, Canada.4Available from the JEDEC Solid State Technology Association, 3103 N. 10thSt., Suite 240-S, Arlington, VA 22201.5Available from National Electrical Manufacturers Association (NEMA), 1300N. 17th St., S
15、uite 1752, Rosslyn, VA 22209, http:/www.nema.org.6Available from RTCA, Inc., 1828 LSt., NW, Suite 805, Washington, DC 20036.7Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001, http:/www.sae.org.1Copyright ASTM International, 100 Barr Harbor Drive, P
16、O Box C700, West Conshohocken, PA 19428-2959, United States.MIL-C-22520/2C Crimping Tools, Terminal, Hand, WireTerminationMIL-S-8802 Sealing Compound, Temperature-Resistant,Integral Fuel Tanks and Fuel Cell Cavities, HighAdhesionMIL-T-7928 Terminal, Lug Splices, Conductors, CrimpStyle, CopperMIL-T-4
17、3435 Tape, Lacing and TyingMS17821 Specification for Cable and Marker Color CodeNumbersMS17822 Specification for Cable and Marker Color CodeNumbersNAVAIR 01-1A-505 Installation PracticesAircraft Elec-tric and Electronic Wiring3. Terminology3.1 Definition:3.1.1 maintenance, ninspection, overhaul, rep
18、air, preser-vation, and the replacement of parts but excludes preventivemaintenance.3.2 Definition of Term Specific to This Standard:3.2.1 electrical wiring interconnection system (EWIS),nas used in this practice, any wire, wiring device, orcombination of these, including termination devices, instal
19、ledin any area of the airplane for the purpose of transmittingelectrical energy between two or more intended terminationpoints.3.3 Acronyms:3.3.1 ACalternating current3.3.2 CFCcarbon fiber composite3.3.3 DCdirect current3.3.4 EDSelectronic data system3.3.5 EMIelectromagnetic interference3.3.6 ESDele
20、ctrostatic discharge3.3.7 EWISelectrical wiring interconnection system3.3.8 ICAOInternational Civil Aviation Organization3.3.9 NiCadnickel cadmium3.3.10 OEMoriginal equipment manufacturer3.3.11 PCpersonal computer3.3.12 PTFEpolytetrafluoroethylene3.3.13 RFradio frequency3.3.14 SOCstate of charge3.3.
21、15 STCsupplemental-type certificate3.3.16 SWAMPsevere wind and moisture problem3.3.17 UVultraviolet4. Significance and Use4.1 This practice is intended to be used as a standard wiringpractice for normal and utility category aircraft when notcontrary to standards published by the aircraft original eq
22、uip-ment manufacturer (OEM) or regulations. This practice isintended to be used for maintenance and preventive mainte-nance of electrical wiring interconnection systems (EWIS).4.2 This practice is not intended to supersede or replace anygovernment specification or specific manufacturers instruc-tion
23、s regarding EWIS maintenance or repair.5. Maintenance5.1 Electrical Systems:5.1.1 Maintenance:5.1.1.1 Scheduled and unscheduled maintenance activities,if done improperly, may contribute to long-term problems anddegradation of wiring. Certain repairs may have limited dura-bility and shall be evaluate
24、d to ascertain if rework is necessary.Repairs that conform to manufacturers recommended mainte-nance practices are generally considered permanent and shouldnot require rework. Care shall be taken to prevent unduecollateral damage to EWIS while performing maintenance onother systems. Metal shavings a
25、nd debris have been discoveredon wire bundles after maintenance, repairs, or modificationshave been performed. Care shall be taken to protect wirebundles and connectors during maintenance and repair. Workareas should be cleaned while the work progresses to ensurethat all shavings and debris are remo
26、ved. The work area shouldbe thoroughly cleaned after work is complete, and the areashall be inspected after the final cleaning. Maintenance, re-pairs, and alterations should be performed using the mosteffective methods available to protect the surrounding EWIS.Since wire splices are more susceptible
27、 to degradation, arcing,and overheating, the recommended method of repairing a wireis with an environmentally sealed splice. (WarningForpersonal safety and to avoid the possibility of fire, turn off allelectrical power before starting an inspection of the aircraftelectrical system or performing main
28、tenance.)5.1.1.2 Repair of any system component that fails an elec-trical measurement test shall conform to manufacturers in-structions and, in lieu of manufacturers manuals, PracticeF2639 or appropriate regulatory guidance materials.5.1.1.3 Wire bundles should be routed in accessible areasthat are
29、protected from damage from personnel, cargo, andmaintenance activity. They should not be routed in areas wherethey are likely to be used as handholds or as support forpersonal equipment or where they could become damagedduring removal of aircraft equipment.5.1.1.4 Replacement wires (see Tables 1 and
30、 2) should beclamped so that contact with equipment and structure isavoided. Where this cannot be accomplished, extra protectionin the form of grommets, chafe strips, and so forth, should beprovided. Protective grommets shall be used wherever wirescannot be clamped in a way that ensures at least a38
31、-in.(9.5-mm) clearance from structure at penetrations.5.1.1.5 Wire should not have a preload against the cornersor edges of chafing strips or grommets. Wiring shall be routedaway from high-temperature equipment and lines to preventdeterioration of insulation. Protective flexible conduits shouldbe ma
32、de of a material and design that eliminates the potentialof chafing between their internal wiring and the conduitinternal walls.5.1.1.6 Replacement wires that shall be routed acrosshinged panels should be routed and clamped so that the bundlewill twist, rather than bend, when the panel is moved.5.1.
33、2 General:5.1.2.1 The term “electrical wiring interconnection system(EWIS)” as used in this practice means any wire, wiringdevice, or combination of these, including termination devices,installed in any area of the airplane for the purpose oftransmitting electrical energy between two or more intende
34、dtermination points.F2799 0925.1.2.2 The satisfactory performance of an aircraft is depen-dent upon the continued reliability of the electrical system.Damaged wiring or equipment in an aircraft, regardless of howminor it may appear to be, cannot be tolerated. Reliability ofthe system is proportional
35、 to the amount of maintenancereceived and the knowledge of those who perform suchmaintenance. It is, therefore, important that maintenance beaccomplished using the best techniques and practices tominimize the possibility of failure.5.1.3 Cleaning and Preservation:5.1.3.1 Annual cleaning of electrica
36、l equipment to removedust, dirt, and grime is recommended.5.1.3.2 If terminals and mating surfaces are corroded ordirty, suitable solvents or fine abrasives that will not score thesurface or remove the plating may be used to clean them. Onlycleaning agents that do not leave any type of residue shall
37、 beused. Avoid using emery cloth to polish commutators or sliprings because particles may cause shorting and burning. Besure that protective finishes are not scored or damaged whencleaning. Ensure that metal-to-metal electrically bonded sur-faces are treated at the interface with a suitable anticorr
38、osiveconductive coating and that the joint is sealed around the edgesby restoring the original primer and paint finish. Connectionsthat shall withstand a highly corrosive environment may beencapsulated with an approved sealant to prevent corrosion.(WarningTurn power off before cleaning.)5.1.3.3 “Pro
39、tect and Clean As You Go” PhilosophyIt isimperative that the technician performing maintenance andTABLE 1 Open WiringDocumentVoltage Rating(Maximum)Rated WireTemperature, CInsulation Type Conductor TypeMIL-W-22759/1A600 200 Fluoropolymer-insulated TFE and TFE coated glass Silver-coated copperMIL-W-2
40、2759/2A600 260 Fluoropolymer-insulated TFE and TFE coated glass Nickel-coated copperMIL-W-22759/3A600 260 Fluoropolymer-insulated TFE-glass-TFE Nickel-coated copperMIL-W-22759/4A600 200 Fluoropolymer-insulated TFE-glass-FEP Silver-coated copperMIL-W-22759/5A600 200 Fluoropolymer-insulated extruded T
41、FE Silver-coated copperMIL-W-22759/6A600 260 Fluoropolymer-insulated extruded TFE Nickel-coated copperMIL-W-22759/7A600 200 Fluoropolymer-insulated extruded TFE Silver-coated copperMIL-W-22759/8A600 260 Fluoropolymer-insulated extruded TFE Nickel-coated copperMIL-W-22759/9A1000 200 Fluoropolymer-ins
42、ulated extruded TFE Silver-coated copperMIL-W-22759/10A1000 260 Fluoropolymer-insulated Nickel-coated copperMIL-W-22759/13A600 135 Fluoropolymer-insulated FEP PVF2 Tin-coated copper,MIL-W-22759/16A600 150 Fluoropolymer-insulated extruded ETFE Tin-coated copper,MIL-W-22759/17A600 150 Fluoropolymer-in
43、sulated extruded ETFE Silver-coated high-strength copper alloyMIL-W-22759/20A1000 200 Fluoropolymer-insulated extruded TFE Silver-coated high-strength copper alloyMIL-W-22759/21A1000 260 Fluoropolymer-insulated extruded TFE Nickel-coated high-strength copper alloyMIL-W-22759/34A600 150 Fluoropolymer
44、-insulated cross-linked modified ETFE Tin-coated copperMIL-W-22759/35A600 200 Fluoropolymer-insulated cross-linked modified ETFE Silver-coated high-strength copper alloyMIL-W-22759/41A600 200 Fluoropolymer-insulated cross-linked modified ETFE Nickel-coated copperMIL-W-22759/42A600 200 Fluoropolymer-
45、insulated cross-linked modified ETFE Nickel-coated high-strength copper alloyMIL-W-22759/43A600 200 Fluoropolymer-insulated cross-linked modified ETFE Silver-coated copperM1L-W-25038/3/2/ 600 260 See specification sheetBSee specification sheetBMIL-W-81044/6 600 150 Cross-linked polyalkene Tin-coated
46、 copperMIL-W-81044/7 600 150 Cross-linked polyalkene Silver-coated high-strength copper alloyMIL-W-81044/9 600 150 Cross-linked polyalkene Tin-coated copperMIL-W-81044/10 600 150 Cross-linked polyalkene Silver-coated high-strength copper alloyMIL-W-81044/12 600 150 Cross-linked polyalkene Tin-coated
47、 copperAMIL-W-22759 has been replaced by SAE AS 22759.BInorganic fibersglassTFE.TABLE 2 Protected WiringDocumentVoltage Rating(Maximum)Rated WireTemperature, CInsulation Type Conductor TypeMIL-W-22759/11A600 200 Fluoropolymer-insulated extruded TFE Silver-coated copperMIL-W-22759/12A600 260 Fluoropo
48、lymer-insulated extruded TFE Nickel-coated copperMIL-W-22759/14A600 135 Fluoropolymer-insulated FEP-PVF2 Tin-coated copperMIL-W-22759/15A600 135 Fluoropolymer-insulated FEP-PVF2 Silver-plated high-strength copper alloyMIL-W-22759/18A600 150 Fluoropolymer-insulated extruded ETFE Tin-coated copperMIL-
49、W-22759/19A600 150 Fluoropolymer-insulated extruded ETFE Silver-coated high-strength copper alloyMIL-W-22759/22A600 200 Fluoropolymer-insulated extruded TFE Silver-coated high-strength copper alloyMIL-W-22759/23A600 260 Fluoropolymer-insulated extruded TFE Nickel-coated high-strength copper alloyMIL-W-22759/32A600 150 Fluoropolymer-insulated cross-linked modified ETFE Tin-coated copperMIL-W-22759/33A600 200 Fluoropolymer-insulated cross-linked modified ETFE Silver-coated high-strength copper alloyMIL-W-22759/44A600 200 Fluoropolymer-insulated c