Electrical Short Circuit/Arcing of Aged Aircraft Wiring

More documents

Recommendations

Info

$Atago Co., Ltd. Salinity Refractometer, Model S-10 Instruction Manual$

Test 15:Bundle: Seven wires (6 over 1) of BMS 42A/8/1-20 specification.Metal Shaving: Aluminum 7075; 70 mils by 8 milsCircuit Resistance: 1 OhmGenerator: 3 phase, 400Hz, 120 line to neutral (208 line to line), 10 kVA.Observations Test 15FlashYesStrong ArcingNoCircuit Breakers TrippedNoDamage Length 0# Wires Failing Wet Dielectric Test 0 of 5This sample flashed immediately and then became dormant. There was no soot depositedand no visible damage to the insulation. None of the circuit breakers tripped and none of the fivewires tested failed the wet dielectric test.The oscilloscope showed was only a ½ cycle of an arcing waveform with a peak currentof 100 amperes. The total electrical energy dissipated in the flash was 2 joules.Electrical Arcing of Aged Aircraft Wire.Lectromechanical Design CompanyReport No. N191-RPT4AU99 August 12, 199944
Metal Shavings AbrasionTest 16 A & B:Metal shaving abrader test 90° (right angle).2 Bundles: Seven wires each of BMS 42A/8/1-20 specification.Metal Shaving: Bundle A: Steel; 41 mils by 26 milsBundle B Aluminum 7075; 42 mils by 30 milsCircuit Resistance: 1 OhmGenerator: 3 phase, 400Hz, 120 line to neutral (208 line to line), 10 kVA.Observations Test 16A Test 16BFlash No NoStrong Arcing No NoCircuit Breakers Tripped No NoDamage Length 0 0# Wires Failing Wet Dielectric Test 1 of 7 2 of 7In this test two samples were run concurrently. Bundles were identical to each otherexcept that bundle A had a steel shaving woven between its wires and bundle B had analuminum 7075 shaving. The test was run for 19 1/4 hours with no arcing events (Figure 38).While the wire sustained some damage in the area of the shaving, the damage was primarily tothe topcoat with the steel shaving doing moderate damage to the Poly X layer (Figure 39).The flexing of the bundles did cause more severe damage in areas away from the shaving.In test A, one of the wire was broken completely in half. In test B, one wire was broken in halfand the insulation on other wire cracked so that the conductor was exposed. These three wiresfailed the wet dielectric test while all of the other wires passed.Electrical Arcing of Aged Aircraft Wire.Lectromechanical Design CompanyReport No. N191-RPT4AU99 August 12, 199945
Page 3 and 4: Electrical Arcing of Aged Aircraft
Page 5 and 6: were placed between wires in small
Page 7 and 8: BackgroundArc tracking of aircraft
Page 9 and 10: EXPERIMENTAL PROCEDURESWet Arc Trac
Page 11 and 12: Figure 5. Circuit used in the metal
Page 13 and 14: Figure 8. Apparatus used for metal
Page 15 and 16: DESCRIPTION OF ELECTRICAL ACTIVITYT
Page 17 and 18: The voltage and current waveforms w
Page 19 and 20: Figure 15. Example of a strong arci
Page 21 and 22: RESULTSTable 1 lists the Test run g
Page 23 and 24: Table 3. Summary of Metal Shavings
Page 25 and 26: APPENDIX A: Description of Individu
Page 27 and 28: Test 1 & 2Wet Arc TrackingBundle: S
Page 29 and 30: Figure 22. Test 1: Oscillogram show
Page 31 and 32: Test 3Wet Arc TrackingBundle: Seven
Page 33 and 34: Figure 26. Test 3: Sample bundle af
Page 35 and 36: Figure 27. Test 4: Strong arcing on
Page 37 and 38: Test 6 & 7Wet Arc TrackingBundle: S
Page 39 and 40: Figure 32. Test 6: Sample bundle af
Page 41 and 42: Test 9:Bundle: Seven wires (6 over
Page 49: Figure 37. Test 14: Electrical powe
Page 53 and 54: Test 17 & 192 Bundles: four wires e
Page 55 and 56: Figure 42. Test 17: Damage to wire
Page 57 and 58: Figure 44. Test 20: Damage done in
Page 59 and 60: Table 7. Description of alternate a

Electrical Short Circuit/Arcing of Aged Aircraft Wiring

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?