EN 3475-409:2002

Overview

EN 3475-409:2002 is a European standard developed by CEN that specifies a test method for assessing the ageing behavior of electrical cables used in aerospace applications when exposed to an air-excluded environment. This standard is part of the aerospace series for aircraft electrical cables and is intended to be used in conjunction with EN 3475-100, which covers general test methods for aerospace cables.

The standard defines a controlled procedure to evaluate how finished aircraft cables perform after undergoing ageing in sealed, oxygen-free conditions. This method aims to simulate conditions where cables might be exposed to environments lacking air and evaluates their durability and integrity over time without oxidative influences.

Key Topics

• Scope: Specifies methods to determine finished cable behavior after ageing in the absence of air.
• Test specimen preparation: Samples of 100 mm length are used for testing.
• Apparatus: Requires a sealed metal tube (typically brass or copper) with specific internal dimensions (120 mm length, 30 mm diameter) and an oven for controlled heating.
• Ageing procedure:
  • The cable specimen is enclosed in the sealed metal tube.
  • The tube is placed in an oven at specified temperatures and durations according to the relevant product standard.
  • Post-ageing, specimens are cooled and physically inspected.
• Acceptance criteria: Cables must show no cracking, splitting, or surface changes such as reversion after being bent to a specified curvature, simulating mechanical stresses following ageing.
• Reference to EN 3475-100: This method is to be used alongside the general aerospace cable test standards defined in EN 3475-100.

Applications

The EN 3475-409:2002 test method is critical for aerospace manufacturers, quality assurance engineers, and cable designers involved in:

• Aircraft electrical cable qualification: Ensuring cable performance under long-term ageing conditions where oxygen or air is excluded.
• Durability testing: Evaluating cable insulation and jacketing materials for resistance to degradation when sealed in airtight environments inside aircraft systems.
• Maintenance and reliability assessments: Predicting potential failures or degradation modes in electrical wiring systems exposed to sealed compartments, such as fuel tanks, avionics bays, or other air-limited spaces.
• Compliance verification: Meeting strict aerospace regulations and standards required by aviation authorities and aerospace manufacturers for in-flight and ground equipment reliability.

Related Standards

• EN 3475-100: Aerospace series - Cables, electrical, aircraft use - Test methods - Part 100: General test methods. This standard provides the foundational testing framework that supports the specific ageing test in EN 3475-409.
• Additional EN 3475 series parts address other environmental and mechanical tests for aerospace electrical cables, ensuring comprehensive cable qualification.
• Relevant international aerospace cable standards from organizations such as SAE and IEC may complement EN 3475-409 in broader certification environments.

Keywords: EN 3475-409, aerospace cable testing, electrical cables aircraft, air-excluded ageing, cable ageing test, aerospace electrical wiring, aircraft cable standards, environmental cable testing, aviation cable durability, electrical cable qualification, CEN aerospace standards