SIST EN 3745-515:2012

Overview

SIST EN 3745-515:2012 is a European standard developed by CEN, specifying test methods for measuring the buffer insertion force of optical fibres and cables used in aerospace applications. This standard focuses on the precise measurement of the force required to move the buffer a specified distance relative to the outer jacket, ensuring consistency and reliability in optical fibre performance within aircraft environments. The standard is particularly relevant for manufacturers, quality control laboratories, and aerospace engineers involved in the design, testing, and certification of fibre optic cables for aircraft use.

Key Topics

• Scope
  Defines procedures for practical measurement of buffer insertion force in aircraft-grade optical fibres and cables, ensuring adherence to aerospace requirements.

• Test Specimens Preparation
  Requires fibres to be terminated with termini suited for semi-loose structured fibre optic cables, with testing lengths and specimen quantities as per applicable product standards.

• Apparatus Requirements

  • Micrometre with minimum 0.1 mm resolution for measuring buffer displacement
  • Force gauge with at least 0.1 N resolution to measure applied force
  • Mechanical fixture to securely clamp terminated specimens during compression testing

• Testing Methodology

  • Terminate both ends of the fibre optic cable specimen
  • Cut assembly midway and clamp one end to prevent buffer movement
  • Apply force on the opposite end to compress ferrule by a specified distance
  • Measure and record the force needed to achieve the specified displacement
  • Repeat for opposite terminus; average values are compared with product standard limits

• Requirements and Compliance
  Recorded average insertion forces must not exceed the maximum values defined in applicable product standards, ensuring optical cable integrity and performance under operational conditions.

Applications

SIST EN 3745-515:2012 is essential for aerospace industry stakeholders involved in optical fibre integration and maintenance, enabling:

• Quality Control and Certification
  Ensures compatibility and durability of fibre optic cables subjected to mechanical forces within aircraft systems.

• Design Validation
  Helps cable designers verify that buffer and jacket materials meet stress and movement tolerance specific to aerospace environments.

• Maintenance and Troubleshooting
  Facilitates periodic testing to detect mechanical issues with fibre cables, supporting preventive maintenance in avionics.

• Aerospace Safety Assurance
  Contributes to reliable data transmission systems critical in aircraft operation and navigation by standardizing cable testing protocols.

Related Standards

Key standards complementing SIST EN 3745-515:2012 in aerospace fibre optic testing include:

• EN 2591-100 - Aerospace series - Elements of electrical and optical connection - General test methods
• EN 2591-601 - Optical elements - Insertion loss measurement methods
• EN 2591-602 - Optical elements - Measurement of attenuation and optical discontinuity variation
• EN 3745-100 - Aerospace series - Fibres and cables, aircraft use - General test methods

These standards collectively cover broader optical fibre testing including electrical connection, loss, attenuation, and mechanical properties critical for aerospace applications.

Keywords: aerospace fibre optic cables, buffer insertion force, optical fibre test methods, aircraft fibre cables, SIST EN 3745-515:2012, buffer movement measurement, fibre optic buffer force, aerospace optical cable testing, CEN standards aerospace, optical cable quality control