EN 3475-509:2002

Overview

EN 3475-509:2002 is a European standard developed by the European Association of Aerospace Manufacturers (AECMA) and published by CEN. This standard specifies the test method for evaluating the solderability of electrical cable conductors and screens or strands taken from aerospace cables used in aircraft. It is an essential part of ensuring the reliability and performance of electrical cable assemblies in aerospace applications.

This standard must be used in conjunction with EN 3475-100, which covers general test methods for aerospace electrical cables. The solderability test defined in EN 3475-509:2002 is critical for assessing the ability of cable conductors to form reliable soldered joints, a key factor in maintaining electrical continuity and integrity in aircraft systems.

Key Topics

• Scope: Provides a method for assessing solderability of aircraft electrical cable conductors and screens.
• Specimen Preparation: Requires careful handling and preparation of cable conductor specimens and strands, including stripping insulation without contamination.
• Test Apparatus: Specifies requirements for the balance, transducer, chart recorder, and solder bath including:
  • Chart recorder response time and sensitivity.
  • Solder bath dimensions and temperature control.
  • Immersion speed and depth control.
• Test Procedure:
  • Specimens are vertically suspended and immersed in molten solder at controlled temperatures.
  • Use of specific solder alloys depending on conductor plating (Sn63 for tin/silver plated, Sn96 for nickel plated).
  • Measurement of wetting time by recording forces via a transducer and chart recorder during immersion.
• Wetting Time Evaluation:
  • The test captures the time interval for solder wetting, reflecting solderability.
  • Maximum allowable wetting time is specified in the relevant product standard.
• Limitations: Not applicable to cable sizes of 020 (gauge 14) and larger.

Applications

EN 3475-509:2002 applies primarily to:

• Aerospace Electrical Cable Manufacturing: Ensuring solderability of conductors for use in aircraft wiring systems.
• Quality Assurance and Testing: Provides standardized test methods for cable manufacturers and aerospace component suppliers.
• Aircraft Maintenance and Certification: Assists in verifying the condition and suitability of cables during maintenance and overhaul.
• Reliability Engineering: Supports design and evaluation activities to ensure joint integrity and long-term performance in demanding aerospace environments.

By applying this standard, aerospace manufacturers and maintenance organizations can reliably assess solderability characteristics, preventing failures due to poor solder joints which could compromise aircraft safety and functionality.

Related Standards

• EN 3475-100: Aerospace series – Cables, electrical, aircraft use – Test methods – General requirements. This standard provides the overarching test methods framework that supports part 509.
• EN 2083: Aerospace series – Copper or copper alloy conductors in electrical cables – Product standard. Defines conductor types and plating relevant to solderability testing.
• Other aerospace cable and electrical system standards published by CEN and AECMA that govern construction, testing, and performance requirements.

Keywords: EN 3475-509, aerospace cable solderability, aircraft electrical cables, solderability test method, aerospace standards, cable conductor testing, solder joint reliability, aircraft wiring standards, EN 3475-100, EN 2083, aerospace electrical cabling.