View Latest Blog Entries
Close
Categories
Testing & Assessment Certification Aging Wires & Systems Standard & Regulation Management Maintenance & Sustainment Conference & Report Research Protection & Prevention Arcing Miscellaneous
Popular Tags
Visual Inspection AS50881 MIL-HDBK MIL-HDBK-525 High Voltage FAR Electromagnetic Interference (EMI) FAR 25.1707 AS4373 Maintenance Wire System Arcing Damage
All Tags in Alphabetical Order
2021 25.1701 25.1703 abrasion AC 33.4-3 Accelerated Aging ADMT Aging Systems AIR6808 AIR7502 Aircraft Power System aircraft safety Aircraft Service Life Extension Program (SLEP) altitude arc damage Arc Damage Modeling Tool Arc Fault (AF) Arc Fault Circuit Breaker (AFCB) Arc Track Resistance Arcing Arcing Damage AS22759 AS22759/87 AS23053 AS4373 AS4373 Method 704 AS50881 AS5692 AS6019 AS83519 AS85049 AS85485 AS85485 Wire Standard ASTM D150 ASTM D8355 ASTM F2696 ASTM F2799 ASTM F3230 ASTM F3309 ATSRAC Attenuation Automated Wire Testing System (AWTS) Automotive backshell batteries Bent Pin Analysis Best of Lectromec Best Practice bonding Cable Cable Bend cable testing Carbon Nanotube (CNT) Certification Chafing Chemical Testing Circuit Breaker circuit design Circuit Protection Coaxial cable cold bend collision comparative analysis Compliance Component Selection Condition Based Maintenance Conductor conductors conduit Connector connector selection connectors contacts Corona Corrosion Corrosion Preventing Compound (CPC) Cracking D-sub data analysis data cables degradat Degradation Delamination Derating design safety development diagnostic Dielectric breakdown dielectric constant Dimensional Life disinfectant Distributed Power System DO-160 dry arc dynamic cut through E-CFR Electrical Aircraft Electrical Component Electrical Power Electrical Testing Electromagnetic Interference (EMI) Electromagnetic Vulnerability (EMV) EMC EMF EN2235 EN3197 EN3475 EN6059 End of Service Life End of Year Energy Storage engines Environmental Environmental Cycling environmental stress ethernet eVTOL EWIS certification EWIS Component EWIS Design EWIS Failure EWIS sustainment EWIS Thermal Management EZAP FAA FAA AC 25.27 FAA AC 25.981-1C FAA Meeting failure conditions Failure Database Failure Modes and Effects Analysis (FMEA) FAQs FAR FAR 25.1703 FAR 25.1707 FAR 25.1709 fault tree Fixturing Flammability fleet reliability Flex Testing fluid exposure Forced Hydrolysis fuel system fuel tank ignition Functional Hazard Assessment functional testing Fundamental Articles Future Tech galvanic corrosion Glycol Gold Gold plating Green Taxiing Grounding hand sanitizer handbook Harness Design Hazard Analysis health monitoring heat shrink heat shrink tubing high current high Frequency high speed data cable High Voltage HIRF History Hot Stamping Humidity Variation HV system ICAs IEC60172 IEEE Inspection installation installation safety Instructions for Continued Airworthiness insulating material insulating tape Insulation insulation breakdown insulation resistance insulation testing interchangeability IPC-D-620 ISO 17025 Certified Lab ISO 9000 J1673 Kapton Laser Marking life limit life limited parts Life prediction life projection Lightning liquid nitrogen lunar maintainability Maintenance Maintenance costs Mandrel mean free path measurement mechanical stress Mechanical Testing MECSIP MIL-C-38999 MIL-C-85485 MIL-DTL-17 MIL-DTL-3885G MIL-DTL-38999 MIL-E-25499 MIL-HDBK MIL-HDBK-1646 MIL-HDBK-217 MIL-HDBK-454 MIL-HDBK-516 MIL-HDBK-522 MIL-HDBK-525 MIL-HDBK-683 MIL-STD-1353 MIL-STD-1560 MIL-STD-1798 MIL-STD-464 MIL-T-7928 MIL-T-81490 MIL-W-22759/87 MIL-W-5088 MIL–STD–5088 Military 5088 modeling moon MS3320 NASA NEMA27500 Nickel nickel plating No Fault Found OEM off gassing Outgassing Over current Overheating of Wire Harness Parallel Arcing part selection Partial Discharge partial discharge at altitude Performance physical hazard assessment Physical Testing polyimdie Polyimide-PTFE Power over Ethernet power system Power systems predictive maintenance Presentation Probability of Failure Product Quality PTFE pull through Radiation Red Plague Corrosion Reduction of Hazardous Substances (RoHS) regulations relays Reliability Research Resistance Revision C Rewiring Project Risk Assessment S&T Meeting SAE SAE Committee Sanitizing Fluids Secondary Harness Protection Separation Requirements Series Arcing Service Life Extension Severe Wind and Moisture-Prone (SWAMP) Severity of Failure shelf life Shield Shielding signal cable Silver silver plated wire silver-plating skin depth skin effect Small aircraft smoke Solid State Circuit Breaker Space Certified Wires Splice standards Storage stored energy supportability Sustainment System Voltage Temperature Rating Temperature Variation Test methods Test Pricing Testing Thermal Circuit Breaker Thermal Endurance Thermal Index Thermal Runaway Thermal Shock Thermal Testing tin Tin plated conductors tin plating tin solder tin whiskering tin whiskers top 5 Transient Troubleshooting TWA800 UAVs UL94 USAF validation verification video Visual Inspection voltage voltage differential Voltage Tolerance vw-1 wet arc white paper whitelisting Wire Ampacity Wire Bend Wire Certification Wire Comparison wire damage wire failure wire performance wire properties Wire System wire testing Wire Verification wiring components work unit code

SAE Wire and Cable Committee Meeting Update – Fall 2019

Conference & Report

The SAE wire and cable committee held their fall 2019 meeting in San Diego this year. As with every committee meeting, a lot of technical areas were discussed, progress was made, and some new ideas/problems are emerged. As we do after all these meetings, we put together a highlight of some of the talking points from the meeting.

New wire standard in the works

There is a new wire standard under development in the SAE 8D committee; this is the first wire standard to be added to the AS22759 group in the last three years (back in 2016, the low fluorine wire specs were added). This new wire construction covers six different specs from AS22759/70 through /75. This family of wires includes common conductor types and plating with a PTFE insulation. While there are already wire specifications in the AS22759 family that are PTFE insulated, the new wire specs increase the performance requirements and raise the bar on several performance levels.

Some of the highlights of this new standard include:

  • Verification of the wet and dry arc track resistance performance.
  • Abrasion resistance requirement at 23, 70, and 150°C.
  • Flex life. This test has not been a common parameter of other AS22759 wire specifications.
  • Corona inception and extinction voltage testing. Similar to flex life, the Corona inception/extinction testing for wires has not been a requirement in the AS22759 wire family.

An interesting element with the wire specs is that the voltage rating still shows a 600 Volt RMS at sea level. While the committee has been talking about high-voltage and the long-term voltage endurance of wires for several years now, the legacy 600V rating on the AS22759 wire constructions remains.

Wire
While most wires look the same on the outside, the differences between two wire types can be startling.

Lastly, the insulation thickness led to additional discussions. Historically, those wire insulation types that have an insulation thickness of eight mils or more were considered normal weight constructions. For those wire constructions with insulation thickness of seven mils or less, the requirement defined these as light weight constructions. While this might not seem as big of a deal, it does impact the wire selection for harness designers and OEMs. The reason for this is that the restrictions in the AS50881 is that normal weight wires are permitted for open harness design (harnesses without secondary harness protection) and are included in table A1 of the standard. Of those wire constructions with insulation thicknesses with 6 mils or less are only permitted in protected wiring applications. For this new family of wires with a wire insulation thickness of seven mils, its fate as a normal or lightweight construction remains to be determined.

High voltage rating

This continues to be a field of interest for the committee and for the industry as more vehicles are pushing the limits of high-voltage systems. When this was originally taken on by the AE-8D committee, the objective was to identify a method to determine the voltage rating for a given wire. As the industry has evolved and higher voltage applications have matured and are starting to be implemented in some vehicles, this task group has grown into something much larger.

The committee continues to gather data to help support the validity of the models being developed, but the progress has been slow. The hope is with some planned testing among the committee members over the next several months, additional data will be available to help move the committee forward.

AEISS

Once every three years, the SAE AE-8 committees come together for the Aerospace Electrical Interconnects Systems Symposium. At this year’s symposium, the papers/presentations were:

  • Replacement of Copper Wiring with Carbon Nanotubes in Aerospace Applications
  • Aircraft EWIS in Naval Aviation
  • Non-Standard Standard Part Performance
  • Evolution of Braid and Overbraid Materials for Aerospace Shielding Applications
  • Impact of High Voltage on Wiring
  • MULTILAM: High Current Density Louvered Electrical Connections for More Electrical Aircraft (MEA) Applications
  • Partial Discharge Modeling taking into account the Electric Field Heterogeneity for Airborne Application
  • A Wire Harness Thermal Testbed for Accurate Ampacity Characterization: Spot Checking the AS50881 Derating Standard
  • History of Wire in Aviation
  • Characterizing Performance of 38999 Connectors for High Speed Copper Interconnects

In a couple of weeks, Lectromec will have an article discussing our presentation on “Non-Standard Standard Part Performance”. This presentation covered research performed by Lectromec into the variability of common QPL’d wire and some of the vast performance differences between these seemingly similar products. To be updated when the next article is released, signup at www.lectromec.com/newsletter.

Michael Traskos

Michael Traskos

President, Lectromec

Michael has been involved in wire degradation and failure assessments for more than a decade. He has worked on dozens of projects assessing the reliability and qualification of EWIS components. Michael is an FAA DER with a delegated authority covering EWIS certification and the chairman of the SAE AE-8A EWIS installation committee.