IEC 61280-4-2:2024

Fibre-optic communication subsystem test procedures - Part 4-2: Installed cabling plant - Single-mode attenuation and optical return loss measurements

IEC 62180-4-2:2024 is applicable to the measurements of attenuation and optical return loss of an installed optical fibre cabling plant using single-mode fibre. This cabling plant can include single-mode optical fibres, connectors, adapters, splices, and other passive devices. The cabling can be installed in a variety of environments including residential, commercial, industrial and data centre premises, as well as outside plant environments. This document is applicable to all single-mode fibre types including those designated by IEC 60793-2-50 as Class B fibres. The principles of this document can be applied to cabling plants containing branching devices (splitters) and at specific wavelength ranges in situations where passive wavelength selective components are deployed, such as WDM, CWDM and DWDM devices. This document is not intended to apply to cabling plants that include active devices such as fibre amplifiers or dynamic channel equalizers. This third edition cancels and replaces the second edition published in 2014. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) addition of the equipment cord method;
b) addition of test limit adjustment related to test cord grades;
c) refinements on measurement uncertainties.

Procédures d’essai des sous-systèmes de télécommunication fibroniques - Partie 4-2: Installations câblées - Mesures de l'affaiblissement de réflexion optique et de l'affaiblissement des fibres unimodales

L'IEC 61280-4-2:2024 s’applique aux mesures de l’affaiblissement et de l’affaiblissement de réflexion optique d’une installation câblée à fibres optiques utilisant des fibres unimodales. Cette installation câblée peut inclure des fibres optiques unimodales, des connecteurs, des adaptateurs, des épissures et d’autres dispositifs passifs. Le câblage peut être installé dans une diversité d’environnements, notamment dans des locaux résidentiels, commerciaux ou industriels et des centres de traitement de données, ainsi que dans des environnements d’installations extérieures. Le présent document s’applique à tous les types de fibres unimodales, y compris celles désignées comme des fibres de Classe B par l’IEC 60793-2-50. Les principes du présent document peuvent s’appliquer aux installations câblées contenant des dispositifs de commutation (répartiteurs) et sur des plages de longueurs d’onde spécifiques, dans des situations dans lesquelles sont déployés des composants passifs sélectifs en longueurs d’onde, par exemple des dispositifs WDM, CWDM et DWDM. Le présent document n’est pas destiné à s’appliquer à des installations câblées qui incluent des dispositifs actifs tels que des amplificateurs à fibres ou des égaliseurs de canaux de transmission dynamiques. Cette troisième édition annule et remplace la deuxième édition parue en 2014. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l’édition précédente:
a) ajout de la méthode des cordons d’équipement;
b) ajout de l’ajustement de limite d’essai lié aux classes de cordons d’essai;
c) affinements des incertitudes de mesure.

General Information

• Status: Published
• Publication Date: 05-May-2024
• ICS: 33.180.01 - Fibre optic systems in general
• Technical Committee: SC 86C - Fibre optic systems and active devices
• Drafting Committee: WG 1 - TC 86/SC 86C/WG 1
• Current Stage: PPUB - Publication issued
• Start Date: 10-May-2024
• Completion Date: 06-May-2024

Relations

• Revises: IEC 61280-4-2:2014 - Fibre-optic communication subsystem test procedures - Part 4-2: Installed cable plant - Single-mode attenuation and optical return loss measurement
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61280-4-2 ®
Edition 3.0 2024-05
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Fibre- optic communication subsystem test procedures –
Part 4-2: Installed cable cabling plant – Single-mode attenuation and optical
return loss measurements
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
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IEC 61280-4-2 ®
Edition 3.0 2024-05
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Fibre- optic communication subsystem test procedures –
Part 4-2: Installed cable cabling plant – Single-mode attenuation and optical
return loss measurements
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.100.01 ISBN 978-2-8322-8892-4
– 2 – IEC 61280-4-2:2024 RLV © IEC 2024
CONTENTS
FOREWORD . 8
INTRODUCTION . 10
1 Scope . 11
2 Normative references . 11
3 Terms, definitions, graphical symbols and abbreviated terms. 12
3.1 Terms and definitions . 12
3.2 Graphical symbols . 15
3.3 Abbreviated terms . 16
4 Measurement methods . 17
4.1 General . 17
4.1.1 Document structure . 17
4.1.2 Attenuation . 17
4.1.3 Optical return loss . 18
4.2 Cabling configurations and applicable test methods . 18
4.2.1 Cabling configurations and applicable test methods for attenuation
measurements . 18
4.2.2 Cabling configurations and applicable test methods for optical return
loss measurements . 23
5 Overview of uncertainties for attenuation measurements . 23
5.1 General . 23
5.2 Sources of significant uncertainties . 24
5.3 Consideration of the power meter . 24
5.4 Consideration of test cord and connector grade . 24
5.4.1 General . 24
5.4.2 Mode field diameter variation . 24
5.5 Reflections from other interfaces. 25
5.6 Optical source . 25
5.7 Output power reference . 25
4.3.6 Received power reference .
5.8 Bi-directional measurements . 25
5.9 Typical uncertainties for attenuation methods A, B, C, and D . 25
5.10 Typical uncertainty values for single-mode attenuation testing for method E . 27
6 Apparatus . 28
6.1 General . 28
6.2 Light source . 28
6.2.1 Stability . 28
6.2.2 Spectral characteristics . 28
6.3 Launch cord . 29
6.4 Receive or tail cords . 29
6.5 Substitution cord . 29
6.6 Power meter – LSPM methods only. 30
6.7 OTDR apparatus . 30
6.8 Return loss test set . 30
6.9 Connector end-face cleaning and inspection equipment . 31
6.10 Adapters . 32
7 Procedures . 32
7.1 General . 32

7.2 Common procedures . 32
7.2.1 Care of the test cords . 32
7.2.2 Make reference measurements (LSPM and OCWR methods only) . 32
7.2.3 Inspect and clean the ends of the fibres in the cabling . 32
7.2.4 Make the measurements . 33
7.2.5 Make the calculations . 33
7.3 Calibration . 33
7.4 Safety . 33
8 Calculations . 33
9 Documentation . 33
9.1 Information for each test . 33
9.2 Information to be made available . 34
Annex A (normative) One-cord reference method . 35
A.1 Applicability of test method . 35
A.2 Apparatus . 35
A.3 Procedure . 35
A.4 Calculation . 36
A.5 Components of reported attenuation . 37
Annex B (normative) Three-cord reference method . 38
B.1 Applicability of test method . 38
B.2 Apparatus . 38
B.3 Procedure . 38
B.4 Calculations . 40
B.5 Components of reported attenuation . 40
Annex C (normative) Two-cord reference method . 42
C.1 Applicability of test method . 42
C.2 Apparatus . 42
C.3 Procedure . 42
C.4 Calculations . 44
C.5 Components of reported attenuation . 44
Annex D (normative) Equipment cord method . 46
D.1 Applicability of the test method . 46
D.2 Apparatus . 46
D.3 Procedure . 46
D.4 Calculation . 47
D.5 Components of reported attenuation . 48
Annex E (normative) Optical time domain reflectometer . 49
E.1 Applicability of test method . 49
E.2 Apparatus . 49
E.2.1 General . 49
E.2.2 OTDR . 49
E.2.3 Test cords . 49
E.3 Procedure (test method) . 50
E.4 Calculation of attenuation . 51
E.4.1 General . 51
E.4.2 Connection location . 52
E.4.3 Definition of the power levels F and F . 54
1 2
E.4.4 Alternative calculation. 56

– 4 – I
...

IEC 61280-4-2 ®
Edition 3.0 2024-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre- optic communication subsystem test procedures –
Part 4-2: Installed cabling plant – Single-mode attenuation and optical return
loss measurements
Procédures d’essai des sous-systèmes de télécommunication fibroniques –
Partie 4-2: Installations câblées – Mesures de l'affaiblissement de réflexion
optique et de l'affaiblissement des fibres unimodales
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

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utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et
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About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

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and withdrawn publications. content tailored to your needs.

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IEC 61280-4-2 ®
Edition 3.0 2024-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre- optic communication subsystem test procedures –

Part 4-2: Installed cabling plant – Single-mode attenuation and optical return

loss measurements
Procédures d’essai des sous-systèmes de télécommunication fibroniques –

Partie 4-2: Installations câblées – Mesures de l'affaiblissement de réflexion

optique et de l'affaiblissement des fibres unimodales

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.01  ISBN 978-2-8322-8789-7

– 2 – IEC 61280-4-2:2024 © IEC 2024
CONTENTS
FOREWORD . 8
INTRODUCTION . 10
1 Scope . 11
2 Normative references . 11
3 Terms, definitions, graphical symbols and abbreviated terms. 12
3.1 Terms and definitions . 12
3.2 Graphical symbols . 14
3.3 Abbreviated terms . 16
4 Measurement methods . 16
4.1 General . 16
4.1.1 Document structure . 16
4.1.2 Attenuation . 17
4.1.3 Optical return loss . 17
4.2 Cabling configurations and applicable test methods . 18
4.2.1 Cabling configurations and applicable test methods for attenuation
measurements . 18
4.2.2 Cabling configurations and applicable test methods for optical return
loss measurements . 22
5 Overview of uncertainties for attenuation measurements . 22
5.1 General . 22
5.2 Sources of significant uncertainties . 22
5.3 Consideration of the power meter . 22
5.4 Consideration of test cord and connector grade . 23
5.4.1 General . 23
5.4.2 Mode field diameter variation . 23
5.5 Reflections from other interfaces. 23
5.6 Optical source . 24
5.7 Output power reference . 24
5.8 Bi-directional measurements . 24
5.9 Typical uncertainties for attenuation methods A, B, C, and D . 24
5.10 Typical uncertainty values for single-mode attenuation testing for method E . 26
6 Apparatus . 26
6.1 General . 26
6.2 Light source . 26
6.2.1 Stability . 26
6.2.2 Spectral characteristics . 27
6.3 Launch cord . 28
6.4 Receive or tail cords . 28
6.5 Substitution cord . 28
6.6 Power meter – LSPM methods only. 28
6.7 OTDR apparatus . 29
6.8 Return loss test set . 29
6.9 Connector end-face cleaning and inspection equipment . 30
6.10 Adapters . 30
7 Procedures . 31
7.1 General . 31
7.2 Common procedures . 31

7.2.1 Care of the test cords . 31
7.2.2 Make reference measurements (LSPM and OCWR methods only) . 31
7.2.3 Inspect and clean the ends of the fibres in the cabling . 31
7.2.4 Make the measurements . 32
7.2.5 Make the calculations . 32
7.3 Calibration . 32
7.4 Safety . 32
8 Calculations . 32
9 Documentation . 32
9.1 Information for each test . 32
9.2 Information to be made available . 33
Annex A (normative) One-cord reference method . 34
A.1 Applicability of test method . 34
A.2 Apparatus . 34
A.3 Procedure . 34
A.4 Calculation . 35
A.5 Components of reported attenuation . 36
Annex B (normative) Three-cord reference method . 37
B.1 Applicability of test method . 37
B.2 Apparatus . 37
B.3 Procedure . 37
B.4 Calculations . 38
B.5 Components of reported attenuation . 38
Annex C (normative) Two
...