SIST EN 4641-401:2024

Aerospace series - Cables, optical 125 μm diameter cladding - Part 401: Tight structure bend insensitive 50 µm/125 µm GI fibre nominal, 1,8 mm outside diameter - Product standard

This document specifies the general characteristics, conditions for qualification, acceptance and quality assurance for a fibre optic cable with a bend-insensitive, 50 µm/125 µm Graded Index fibre core, 1,8 mm outside diameter for non pull-proof contact designs.

Luft- und Raumfahrt - Lichtwellenleiterkabel, Mantelaußendurchmesser 125 μm - Teil 401: Festaderaufbau 50 μm/125 μm GI-Faser, Kabelaußendurchmesser 1,8 mm - Produktnorm

Dieses Dokument legt die allgemeinen Eigenschaften, Bedingungen für Qualifikation, Abnahme und Qualitätssicherung für ein Lichtwellenleiterkabel mit einem biege-unempfindlichen 50 µm/125 µm-Gradientenindexfaserkern und einem Außendurchmesser von 1,8 mm für nicht zugfeste Kontaktausführungen fest.

Série Aérospatiale - Câbles, optiques, diamètre extérieur de la gaine optique 125 μm - Partie 401 : Câble à structure serrée, fibre à gradient d’indice 50 μm/125 μm insensible à la courbure, diamètre extérieur 1,8 mm - Norme de produit

Le présent document spécifie les caractéristiques générales ainsi que les conditions de qualification, de réception et d'assurance qualité pour un câble à fibre optique avec une âme de fibre à gradient d'indice 50/125 µm insensible à la courbure, un diamètre extérieur de 1,8 mm, pour les conceptions de contact résistant à la traction.

Aeronavtika - Kabli z optično prevleko premera 125 μm - 401. del: Tesna struktura, neobčutljiva na upogib 50 μm/125 μm GI vlakna, nominalni zunanji premer 1,8 mm - Standard izdelka

Ta dokument določa splošne značilnosti ter pogoje kvalifikacije, sprejemljivosti in zagotavljanja kakovosti za optični kabel z jedrom iz gradientnih indeksnih vlaken 50/125 µm, neobčutljivim na upogib, ter zunanjim premerom 1,8 mm za spoje, ki se v primeru sile ne razdružijo.

General Information

• Status: Published
• Publication Date: 21-Oct-2024
• ICS: 33.180.10 - Fibres and cables
• ICS: 49.090 - On-board equipment and instruments
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 15-Oct-2024
• Due Date: 20-Dec-2024
• Completion Date: 22-Oct-2024
• Ref Project: EN 4641-401:2024 - Aerospace series - Cables, optical 125 μm diameter cladding - Part 401: Tight structure bend insensitive 50 µm/125 µm GI fibre nominal, 1,8 mm outside diameter - Product standard

Overview

EN 4641-401:2024 is a CEN product standard in the Aerospace series that specifies the characteristics, qualification, acceptance and quality assurance requirements for a tight‑structure, bend‑insensitive 50 µm/125 µm graded‑index (GI) optical fibre cable with a nominal 1,8 mm outside diameter. The standard covers cables intended for non pull‑proof contact designs used in on‑board aircraft and aerospace equipment, defining construction, materials, environmental limits and test criteria.

Key topics and technical requirements

• Cable construction and dimensions
  • Core: 50 ± 2,5 µm; cladding: 125 ± 1,0 µm
  • Finished cable diameter: 1,80 mm ± 0,10 mm
  • Secondary buffer: 900 ± 60 µm; optional primary buffer
• Optical performance
  • Attenuation: ≤ 4,0 dB/km at 850 nm and ≤ 2,0 dB/km at 1 300 nm (at +20 °C)
  • Numerical aperture: 0,200 ± 0,015 at 850 nm
  • Bandwidth: ≥ 1 500 MHz·km at 850 nm; ≥ 500 MHz·km at 1 300 nm
• Mechanical and environmental
  • Operating temperature: −65 °C to +135 °C
  • Minimum bend radius (installation/long term): 10 mm at +20 °C; storage: 40 mm
  • Tensile strength: ≥ 500 N
  • Strength member: aramid reinforcement; jacket and buffers: fluoropolymers and polyacrylate
• Qualification and testing
  • Extensive test matrix referenced to the EN 3745 series: visual inspection, dimensional checks, attenuation, NA, bandwidth, thermal cycling, ageing, humidity, resistance to fluids, micro‑bending, tensile, impact, abrasion, flammability, smoke and toxicity where applicable
  • Quality assurance, marking, packaging and delivery length requirements

Applications and who uses this standard

• Aerospace OEMs and system integrators specifying on‑board fibre for data links, sensors and avionics harnesses where tight bend performance and small diameter are critical
• Cable manufacturers designing and qualifying bend‑insensitive 50/125 GI fibre optic cables to meet aerospace acceptance criteria
• Procurement and certification teams ensuring suppliers meet standardized tests, materials and traceability
• Maintenance and repair organisations (MROs) selecting replacement cables compatible with aircraft installation constraints

Related standards

• EN 3745 series (optical fibre & cable test methods)
• EN 4641-001 (Aerospace series - Technical specification)
• EN 2424 (marking) and EN 2812 (stripping) - referenced for related processes and marking

EN 4641-401:2024 is essential for specifying compact, bend‑insensitive aerospace optical cabling that meets strict dimensional, optical and environmental requirements for reliable on‑board data transmission.

Standards Content (Sample)

SLOVENSKI STANDARD
01-december-2024
Aeronavtika - Kabli z optično prevleko premera 125 μm - 401. del: Tesna struktura,
neobčutljiva na upogib 50 μm/125 μm GI vlakna, nominalni zunanji premer 1,8 mm
- Standard izdelka
Aerospace series - Cables, optical 125 μm diameter cladding - Part 401: Tight structure
bend insensitive 50 µm/125 µm GI fibre nominal, 1,8 mm outside diameter - Product
standard
Luft- und Raumfahrt - Lichtwellenleiterkabel, Mantelaußendurchmesser 125 μm - Teil
401: Festaderaufbau 50 μm/125 μm GI-Faser, Kabelaußendurchmesser 1,8 mm -
Produktnorm
Série Aérospatiale - Câbles, optiques, diamètre extérieur de la gaine optique 125 μm -
Partie 401 : Câble à structure serrée, fibre à gradient d’indice 50 μm/125 μm insensible à
la courbure, diamètre extérieur 1,8 mm - Norme de produit
Ta slovenski standard je istoveten z: EN 4641-401:2024
ICS:
33.180.10 (Optična) vlakna in kabli Fibres and cables
49.090 Oprema in instrumenti v On-board equipment and
zračnih in vesoljskih plovilih instruments
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 4641-401
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2024
EUROPÄISCHE NORM
ICS 49.090
English Version
Aerospace series - Cables, optical 125 µm diameter
cladding - Part 401: Tight structure bend insensitive 50
µm/125 µm GI fibre nominal, 1,8 mm outside diameter -
Product standard
Série Aérospatiale - Câbles, optiques, diamètre Luft- und Raumfahrt - Lichtwellenleiterkabel,
extérieur de la gaine optique 125 µm - Partie 401 : Mantelaußendurchmesser 125 µm - Teil 401:
Câble à structure serrée, fibre à gradient d'indice 50 Festaderaufbau 50 µm/125 µm GI-Faser,
µm/125 µm insensible à la courbure, diamètre Kabelaußendurchmesser 1,8 mm - Produktnorm
extérieur 1,8 mm - Norme de produit
This European Standard was approved by CEN on 17 June 2024.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 4641-401:2024 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 6
4 Required characteristics . 6
5 Cable construction . 7
6 Materials . 8
7 Test methods and performances . 8
7.1 Tests in accordance with EN 3745-100 . 8
7.1.1 Optical fibre . 8
7.1.2 Fibre optic cable . 9
7.2 Fluids test. 16
8 Tooling . 17
9 Quality assurance . 17
10 Designation and marking . 17
10.1 General principle of designation . 17
10.2 Marking . 17
10.3 Colours . 18
11 Delivery conditions . 18
11.1 Packaging . 18
11.2 Labelling . 18
11.3 Delivery lengths. 18
12 Storage . 18
13 Technical specification . 18
Bibliography . 19

European foreword
This document (EN 4641-401:2024) has been prepared by ASD-STAN.
After enquiries and votes carried out in accordance with the rules of this Association, this document has
received the approval of the National Associations and the Official Services of the member countries of
ASD-STAN, prior to its presentation to CEN.
This document shall be given the status of a national standard, either by publication of an identical text
or by endorsement, at the latest by April 2025, and conflicting national standards shall be withdrawn at
the latest by April 2025.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent
rights.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this document: Austria, Belgium, Bulgaria, Croatia, Cyprus,
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North
Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the United
Kingdom.
1 Scope
This document specifies the general characteristics, conditions for qualification, acceptance and quality
assurance for a fibre optic cable with a bend-insensitive, 50 µm/125 µm Graded Index fibre core,
1,8 mm outside diameter for non pull-proof contact designs.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 2424, Aerospace series — Marking of aerospace products
EN 2812, Aerospace series — Stripping of electric cables
EN 3475-601, Aerospace series — Cables, electrical, aircraft use — Test methods — Part 601: Smoke
density
EN 3745-201, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 201:
Visual examination
EN 3745-202, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 202:
Fibre dimensions
EN 3745-203, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 203:
Cable dimensions
EN 3745-205, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 205:
Cable longitudinal dimensional stability
EN 3745-301, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 301:
Attenuation
EN 3745-302, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 302:
Numerical aperture
EN 3745-303, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 303:
Bandwidth
EN 3745-305, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 305:
Immunity to ambient light coupling
Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 306:
EN 3745-306,
Variation of attenuation during temperature cycling
EN 3745-401, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 401:
Accelerated ageing
Published as ASD-STAN prEN at the date of publication of this document, available at: https://www.asd-
stan.org/.
EN 3745-404, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 404:
Thermal shock
EN 3745-405, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 405:
Low/High temperature bend test
EN 3745-407, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 407:
Flammability
EN 3745-410, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 410:
Thermal life
EN 3745-411, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 411:
Resistance to fluids
EN 3745-412, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 412:
Humidity resistance
EN 3745-501, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 501:
Optical fibre proof test
EN 3745-503, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 503:
Scrape abrasion
EN 3745-504, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 504:
Micro bending test
EN 3745-505, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 505:
Cable tensile strength
EN 3745-506, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 506:
Impact resistance
EN 3745-507, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 507:
Cut-through
EN 3745-508, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 508:
Torsion
EN 3745-509, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 509:
Kink test
EN 3745-510, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 510:
Bending test
EN 3745-511, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 511:
Cable to cable abrasion
EN 3745-512, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 512:
Flexure endurance
EN 3745-513, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 513:
Crush resistance
EN 3745-517, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 517:
Cable tie clamping test
EN 3745-601, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 601:
Smoke density
EN 3745-602, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 602:
Toxicity
EN 3745-701, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 701:
Strippability
EN 3745-703, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 703:
Durability of manufacturer's marking
EN 3745-705, Aerospace series — Fibres and cables, optical, aircraft use — Test methods — Part 705:
Contrast measurement
EN 3838, Aerospace series — Requirements and tests on user-applied markings on aircraft
electrical cables
EN 3909, Aerospace series — Test fluids and test methods for electrical and optical components and sub-
assemblies
EN 4641-001, Aerospace series — Cables, optical, 125 µm diameter cladding — Part 001: Technical
specification
TR 6058, Cable code identification list
3 Terms and definitions
For the purposes of this document, the definitions, symbols and abbreviations given in
EN 3745-100 apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp/
— IEC Electropedia: available at https://www.electropedia.org/
4 Required characteristics
The characteristics of the cables, tested according to the methods described hereafter shall comply with
the values defined in this product standard.

Published as ASD-STAN TR, available at: https://www.asd-stan.org/.
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