SIST EN 3475-415:2006

Overview

EN 3475-415:2005 - "Aerospace series - Cables, electrical, aircraft use - Test methods - Part 415: Rapid change of temperature" is a CEN product standard that defines a laboratory test method to evaluate the performance of coaxial cables after exposure to rapid temperature changes. It is intended to be used together with EN 3475-100 (general test provisions) and references measurement methods for capacitance and attenuation.

Key topics and requirements

• Scope: Test method for coaxial cable performance following rapid temperature change cycles; applicability and limiting temperatures (TA and TB) are taken from the applicable product standard.
• Specimens
  • First specimen: length as specified in the product standard.
  • Second specimen: length = 1.5 m (cut from specimen unit).
  • During temperature exposure specimens must not be bent with radius < 30 × overall cable diameter.
• Measurements (initial and final)
  • Capacitance per unit length (measured per EN 3475-801).
  • Attenuation at 200 MHz (measured per EN 3475-806).
  • For the second specimen: measure any relative length change between dielectric and conductor (shrinkage/expansion).
• Temperature cycle
  • Specimen is subjected to the specified temperature cycle for a total of three cycles.
  • Key timings: conditioning at each extreme t1 = 4 hours, rapid transition t2 < 2 minutes, post-extreme conditioning t3 > 4 hours. After the conditioning period, remove specimen and condition at room temperature for minimum 4 hours before final measurements.
• Pass/fail criteria
  • Maximum allowable variation in capacitance, maximum allowable increase in attenuation, and maximum shrinkage/expansion are those specified in the product standard for the cable under test (EN 3475 product specification).

Applications and users

• Practical use: qualifying and verifying coaxial aircraft cables for resistance to rapid thermal transients encountered in flight, ground operations, or environmental testing.
• Typical users:
  • Aerospace manufacturers and suppliers (cable design and qualification)
  • Environmental and electrical test laboratories
  • Procurement and quality assurance teams specifying cable acceptance criteria
  • Certification bodies and maintenance organizations validating cable integrity

Related standards

• EN 3475-100 - General test methods for aerospace cables
• EN 3475-801 - Capacitance per unit length (measurement method)
• EN 3475-806 - Attenuation measurement at specified frequency

Keywords: EN 3475-415:2005, rapid change of temperature, coaxial cable test, aerospace cable testing, capacitance per unit length, attenuation 200 MHz, temperature cycling, cable qualification.