SIST EN 2591-612:2004

Overview

EN 2591-612:2001 is a CEN/AECMA aerospace series standard that specifies a test method for checking the effectiveness of cable attachment in the axial compression mode for optical connection elements, including permanent connections and fibre optic couplers. It is intended to be used together with EN 2591-100 (general test methods) and forms part of the EN 2591 test-method family for aerospace electrical and optical connectors.

Key topics and technical requirements

• Scope: Defines a reproducible method to assess whether an optical connector’s cable retention resists axial compression without degrading optical performance or causing mechanical damage.
• Specimen preparation: Specimens must be fitted with normal accessories, terminated per the product standard, and stabilized at standard test conditions for 24 hours as defined in EN 2591-100.
• Apparatus and set‑up:
  • A holding device that grips the cable or cable bundle at a distance L equal to three times the cable/bundle diameter from the rigid retention device.
  • A suitable gauge to measure the compression force between the cable and the optical connection element.
  • A typical test arrangement is illustrated in the standard (figure referenced).
• Test procedure:
  • The standard applies axial compression forces defined in Table 1 (forces vary according to cable or bundle diameter).
  • The specified compression force is applied for a defined duration (the force is applied for two minutes).
  • Attenuation is monitored continuously during the test using the method in EN 2591-602 (Method A) to detect variation of attenuation and optical discontinuities.
• Final assessments:
  • Visual examination in accordance with EN 2591-6101.
  • Measurement of insertion loss according to EN 2591-601.
• Parameters to be specified (unless stated in product technical specification): applied load, speed of operation, maximum permissible variation of attenuation, maximum insertion loss, and cable/fibre type and length.

Applications and who uses it

• Used by aerospace manufacturers, connector designers, supplier test laboratories, quality assurance teams, and certification bodies to:
  • Verify mechanical retention and optical integrity of fibre-optic connectors under axial compression.
  • Ensure compliance with aerospace connector performance requirements during design validation, incoming inspection, and qualification testing.
  • Reduce risk of signal degradation or connector failure in aircraft and spaceflight applications where axial loads may occur.

Related standards

• EN 2591-100 - General test methods (normative)
• EN 2591-601 - Optical elements - Insertion loss
• EN 2591-602 - Optical elements - Variation of attenuation and optical discontinuity
• EN 2591-6101 - Optical elements - Visual examination

Keywords: EN 2591-612:2001, cable axial compression, optical elements, cable attachment, aerospace series, test methods, fibre optic couplers, insertion loss, attenuation monitoring.