SIST EN 3475-506:2007

Overview

EN 3475-506:2007 - "Aerospace series - Cables, electrical, aircraft use - Test methods - Part 506: Plating continuity" defines a laboratory method to verify the continuity and integrity of metallic plating on cable strands and screens used in aircraft electrical wiring. The standard covers plating verification both for strands checked before stranding/screening and for finished stranded or screened conductors. It is intended to be used together with EN 3475-100 (general test methods for aerospace cables).

Key topics and requirements

• Scope: Applies to plated strands (copper, copper-clad aluminium, screens) checked either before or after stranding/screening.
• Specimen preparation:
  • Prepare three specimens, minimum 150 mm long; immersed length at least 110 mm.
  • Degrease and handle specimens to avoid contamination (do not touch cleaned surfaces with bare fingers).
  • For copper-clad aluminium specimens, wind five turns on a mandrel about 12 times the strand diameter to reveal coating weakness.
  • For stranded/screened constructions, test whole conductors or selected members per construction (unilay/concentric, rope layers, separated screens).
• Test method:
  • Immerse specimens for 30 s in a sodium polysulphide solution (density 1.142 g/cm3 at 20 °C), then rinse in distilled water.
  • For silver-plated specimens only: additional immersion 15 s in hydrochloric acid (density 1.088 g/cm3 at 20 °C), then rinse.
• Acceptance criteria:
  • Inspect immediately after the solution cycle. There must be no adherent or distinctly visible black spots when examined by the naked eye.
  • Any blackening occurring within 15 mm of each end of the specimen is disregarded.
• Normative references: EN 3475-100 and relevant ASTM plating specifications (ASTM B33, B298, B355) are cited for applicability and material definitions.

Applications and users

• Cable manufacturers: Quality control during plating and post-plating inspection to ensure coating continuity and corrosion protection.
• Aerospace OEMs and suppliers: Verifying plated conductors and screens used in aircraft electrical systems meet aerospace test methods.
• Independent test laboratories: Routine acceptance and failure analysis testing of plated wires, copper and copper-clad aluminium conductors, and cable screens.
• Procurement and quality engineers: Specification and verification of plating integrity as part of supplier qualification and incoming inspection.

Related standards

• EN 3475-100 - General test methods for aerospace cables (must be used together with Part 506).
• ASTM B33, B298, B355 - Material specifications referenced for plated wire types.

Keywords: EN 3475-506:2007, plating continuity, aerospace cables, test methods, polysulphide test, copper-clad aluminum, cable screening, plating verification, aircraft electrical wiring.