IEC 60794-2-20:2024

Optical fibre cables - Part 2-20: Indoor cables - Family specification for multi-fibre optical cables

IEC 60794-2-20:2024 is part of a family specification covering multi-fibre optical cables for indoor use. The requirements of the sectional specification IEC 60794-2 are applicable to cables covered by this document. Annex B contains a blank detail specification and general guidance in case the cables are intended to be used in installations governed by the MICE table of ISO/IEC 11801-1. This fourth edition cancels and replaces the third edition published in 2013. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) update of the normative references;
b) review update of parameters and requirements for mechanical tests and environmental tests, maintaining alignment with additional relevant standards in the IEC 60794-2 series;
c) addition of cabled fibre attenuation requirements;
d) addition of cable design examples.
This document is to be used in conjunction with IEC 60794-1-1:2023, IEC 60794-1-2:2021, IEC 60794‑1‑21:2015 and IEC 60794‑1‑21:2015/AMD:2020, IEC 60794-1-22:2017, IEC 60794‑1-23:2019 and IEC 60794‑2:2017.

Câbles à fibres optiques - Partie 2-20 : Câbles intérieurs - Spécification de famille pour les câbles optiques multifibres

IEC 60794-2-20:2024 fait partie une spécification de famille qui couvre les câbles optiques multifibres pour utilisation intérieure. Les exigences de la spécification intermédiaire IEC 60794-2 sont applicables aux câbles couverts par le présent document. L’Annexe B contient une spécification particulière-cadre et des recommandations générales dans le cas où les câbles sont destinés à être utilisés dans des installations régies par la matrice MICE de l’ISO/IEC 11801-1.
Cette quatrième édition annule et remplace la troisième édition parue en 2013. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l’édition précédente:
a) mise à jour des références normatives;
b) révision-mise à jour des paramètres et des exigences pour les essais mécaniques et les essais d’environnement, en conservant l’alignement avec les normes pertinentes supplémentaires de la série IEC 60794-2;
c) ajout des exigences relatives à l’affaiblissement des fibres câblées;
d) ajout d’exemples de conceptions de câble.
Le présent document est à utiliser conjointement avec l’IEC 60794-1-1:2023, l’IEC 60794‑1‑2:2021, l’IEC 60794-1-21:2015 associée à l’IEC 60794-1-21:2015/AMD:2020, l’IEC 60794-1-22:2017, l’IEC 60794-1-23:2019 et l’IEC 60794-2:2017.

General Information

• Status: Published
• Publication Date: 10-Dec-2024
• ICS: 33.180.01 - Fibre optic systems in general
• Technical Committee: SC 86A - Fibres and cables
• Current Stage: PPUB - Publication issued
• Start Date: 10-Jan-2025
• Completion Date: 11-Dec-2024

Relations

• Revises: IEC 60794-2-20:2013 - Optical fibre cables - Part 2-20: Indoor cables - Family specification for multi-fibre optical cables
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60794-2-20 ®
Edition 4.0 2024-12
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Optical fibre cables –
Part 2-20: Indoor cables – Family specification for multi-fibre optical cables

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IEC 60794-2-20 ®
Edition 4.0 2024-12
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Optical fibre cables –
Part 2-20: Indoor cables – Family specification for multi-fibre optical cables
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.180.01 ISBN 978-2-8327-0104-1

– 2 – IEC 60794-2-20:2024 RLV © IEC 2024
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Construction . 7
4.1 General . 7
4.2 Optical fibres . 8
4.3 Buffer . 8
4.4 Ruggedized fibre . 8
4.5 Slotted core . 8
4.6 Tube . 9
4.7 Stranded tube . 9
4.8 Ribbon structure . 9
4.9 Strength and anti-buckling members . 9
4.10 Ripcord . 9
4.11 Sheath . 9
4.12 Sheath marking . 9
4.13 Identification . 9
4.14 Examples of cable constructions . 10
5 Tests . 10
5.1 General . 10
5.2 Dimensions . 10
5.3 Mechanical requirements . 10
5.3.1 CableTensile performance . 10
5.3.2 CableCrush . 11
5.3.3 CableImpact . 11
5.3.4 CableBending . 11
5.3.5 CableRepeated bending . 12
5.3.6 CableBending under tension . 12
5.3.7 CableBending at low temperature . 12
5.3.8 CableFlexing . 12
5.3.9 CableTorsion . 12
5.3.10 Cable Kink . 13
5.4 Environmental requirements – Temperature cycling . 13
5.5 Transmission requirements . 14
5.5.1 General . 14
5.5.2 Single-mode optical fibres . 14
5.5.3 Single-mode dispersion unshifted (B-652.B) optical fibre . 14
5.5.4 Single-mode dispersion unshifted (B-652.D) optical fibre . 15
5.5.5 Single-mode (B-657.A) optical fibre . 15
5.5.6 Single-mode (B-657.B) optical fibre . 15
5.5.7 Multimode optical fibres . 15
5.5.8 Multimode (A1-OM1 to A1-OM5) optical fibres . 16
5.6 Fire performance . 16
Annex A (informative) Examples of cable constructions . 17
Annex B (informative) Family specification for multi-fibre optical cables – Blank detail
specification and minimum requirements . 22

B.1 Blank detail specification . 22
B.1.1 General . 22
B.1.2 Cable description . 22
B.1.3 Cable element . 23
B.1.4 Cable construction . 24
B.1.5 Installation and operating conditions . 25
B.1.6 Mechanical and environmental tests . 25
B.2 Cables subject to the MICE environmental classification (ISO/IEC 11801-1
and related standards) . 26
Bibliography . 27

Figure A.1 – Example of cross-section of a 12-fibre cable . 17
Figure A.2 – Example of cross-section of a 36-fibre cable . 17
Figure A.3 – Example of cross-section of a 6-fibre break-out cable . 18
Figure A.4 – Example of cross-section of a 24-fibre break-out cable . 18
Figure A.5 – Example of cross-section of a slotted core type indoor cable with 4-fibre
ribbons . 19
Figure A.6 – Example of cross-section of an SZ (reverse oscillating lay) slotted core
type indoor cable with 2-fibre ribbons . 19
Figure A.7 – Example of cross-section of an SZ (reverse oscillating lay) slotted core
type indoor cable with 4-fibre bundles . 20
Figure A.8 – Example of multi-fibre unitube cable . 20
Figure A.9 – Example of multi-fibre cable . 20
Figure A.10 – Example of a retractable (micro-module) cable . 21

Table 1 – Dimensions of buffered fibres . 8
Table 2 – Sample temperature cycling values .
Table 2 – Typical values for temperature cycling . 13
Table 3 – Common single-mode optical fibre requirements . 14
Table 4 – Cabled fibre attenuation requirements for B-652.B optical fibre . 14
Table 5 – Cabled fibre attenuation requirements for B-652.D optical fibre . 15
Table 6 – Cabled fibre attenuation requirements for B-657.A optical fibre . 15
Table 7 – Cabled fibre attenuation requirements for B-657.B optical fibre . 15
Table 8 – Common multimode optical fibre requirements . 15
Table 9 – Cabled fibre attenuation requirements for A1-OM1 to A1-OM5 optical fibres . 16
Table B.1 – Cable description . 22
Table B.2 – Cable element . 23
Table B.3 – Cable construction . 24
Table B.4 – Installation and operating conditions . 25
Table B.5 – Tests applicable . 25

– 4 – IEC 60794-2-20:2024 RLV © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL FIBRE CABLES –
Part 2-20: Indoor cables –
Family specification for multi-fibre optical cables

FOREWORD
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