SIST EN 3475-701:2018

Overview

EN 3475-701:2017 (CEN) specifies standardized test methods to measure the strippability of cable jackets and the adherence of insulation to conductors for finished aircraft cables. The standard defines specimen preparation, two test methods for adherence (Method A and Method B), and requirements for acceptable performance. It is intended to be used together with EN 3475-100 and references EN 2812 for stripping tools.

Key practical facts:

• Default method: Method A is the default when the detail product specification does not require otherwise.
• When to use Method B: Recommended for wires with low adhesion to the conductor because Method A can show poor repeatability for such materials.
• Reference tests: Use EN 3475-100 for general test practices and EN 2812 for stripping tool specifications.

Key Topics

• Specimen preparation: Samples shall be measured directly from a reel or coil with minimal deformation. Stripping shall be performed at the two ends of each specimen using tools conforming to EN 2812.
• Stripping lengths: For insulation stripping properties, the insulation must be stripped over 5 mm for cables up to 5 mm2 and over 8 mm for cables greater than 5 mm2 at each specimen end.
• Adherence test layouts:
  • Method A: insulation cut around the periphery at 5 mm and 30 mm from one end (for sizes up to 5 mm2) and the remaining insulation left on the conductor.
  • Method B: insulation cut at 5 mm and 55 mm from one end; required when low adhesion materials are present.
• Force test procedure: For both methods the conductor is passed through a calibrated hole of diameter (conductor diameter + 0,05 mm) and subjected to an increasing tensile force until sliding occurs. The tensile speed is (100 ± 10) mm/min.
• Measurement rules: Method B requires three initial measurements per sample; if one measurement is below the product limit, two additional measurements are taken and the median of five measurements is used.
• Stripping capability timing: For screened cables, the jacket stripping operation shall not exceed 40 s for a suitably skilled operator when stripping an 80 mm length.

Applications

This standard is essential for aerospace and defense manufacturers, cable designers, quality engineers, and test laboratories involved in aircraft wiring. It ensures:

• Consistent evaluation of insulation adhesion for reliable electrical and mechanical performance
• Informed selection between Method A and Method B for materials with different adhesion characteristics
• Compliance evidence for product specifications and procurement requirements

Related Standards

• EN 3475-100 - General test methods for aerospace cables (use in conjunction with EN 3475-701)
• EN 2812 - Stripping tools and stripping procedure references

Use EN 3475-701:2017 as the authoritative test method reference when documenting cable qualification, supplier testing protocols, and acceptance criteria for aircraft electrical wiring systems.