IEC 61280-4-1:2009

Fibre-optic communication subsystem test procedures - Part 4-1: Installed cable plant - Multimode attenuation measurement

IEC 61280-4-1:2009 is applicable to the measurement of attenuation of installed fibre-optic cabling using multimode fibre, typically in lengths of up to 2 000 m. This cabling can include multimode fibres, connectors, adapters and splices. In this standard, the fibre types that are addressed include category A1a (50/125 µm) and A1b (62,5/125 µm) multimode fibres, as specified in IEC 60793-2-10. The attenuation measurements of the other multimode categories can be made, using the approaches of this standard, but the source conditions for the other categories have not been defined. The main changes with respect to the previous edition are:
- An additional measurement method based on optical time domain reflectometry (OTDR) is documented, with guidance on best practice in using the OTDR and interpreting OTDR traces.
- The requirement for the sources used to measure multimode fibres is changed from one based on coupled power ratio (CPR) and mandrel requirement to one based on measurements of the near field at the output of the launching test cord.
- Highlighting the importance of, and giving guidance on, good measurement practices including cleaning and inspection of connector end faces.

Procédures d'essai des sous-systèmes de télécommunication à fibres optiques - Partie 4-1: Installations câblées - Mesure de l'affaiblissement en multimodal

La CEI 61280-4-1:2009 s'applique à la mesure de l'affaiblissement d'une installation de câblage en fibre optique utilisant des fibres multimodes, généralement sur des longueurs allant jusqu'à 2 000 m. Cette installation de câblage peut inclure des fibres multimodes, des connecteurs, des raccords et des épissures. Dans la présente norme, les types de fibres abordées comportent les fibres multimodes de catégorie A1a (50/125 µm) et A1b (62,5/125 µm) spécifiées dans la CEI 60793-2-10. Les mesures d'affaiblissement des autres catégories multimodales peuvent être effectuées en utilisant les approches de la présente norme, mais les conditions de source des autres catégories n'ont pas été définies. Les principales modifications portant sur cette précédente édition sont:
- Une méthode de mesure supplémentaire basée sur la réflectométrie optique dans le domaine temporel (OTDR) est rapportée, avec des indications sur les meilleures pratiques d'utilisation de l'OTDR et d'interprétation des tracés de l'OTDR.
- L'exigence concernant les sources utilisées pour mesurer les fibres multimodes passe d'une exigence basée sur le taux de puissance couplée (CPR) et l'exigence relative au mandrin à une exigence basée sur des mesures en champ proche à la sortie du cordon d'essai d'amorce.
- La mise en valeur de l'importance et la fourniture de directives sur de bonnes pratiques de mesure incluant le nettoyage et l'examen des faces d'extrémité des connecteurs.

General Information

• Status: Published
• Publication Date: 09-Jun-2009
• 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: DELPUB - Deleted Publication
• Completion Date: 22-May-2019

Relations

• Revises: IEC 61280-4-1:2003 - Fibre-optic communication subsystem test procedures - Part 4-1: Cable plant and links - Multimode fibre-optic cable plant attenuation measurement
• Effective Date: 05-Sep-2023
• Revised: IEC 61280-4-1:2019 - Fibre-optic communication subsystem test procedures - Part 4-1: Installed cabling plant - Multimode attenuation measurement
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61280-4-1 ®
Edition 2.0 2009-06
INTERNATIONAL
STANDARD
Fibre-optic communication subsystem test procedures –
Part 4-1: Installed cable plant – Multimode attenuation measurement

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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About the IEC
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International Standards for all electrical, electronic and related technologies.

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IEC 61280-4-1 ®
Edition 2.0 2009-06
INTERNATIONAL
STANDARD
Fibre-optic communication subsystem test procedures –
Part 4-1: Installed cable plant – Multimode attenuation measurement

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XB
ICS 33.180.01 ISBN 978-2-88910-478-9
– 2 – 61280-4-1 © IEC:2009(E)
CONTENTS
FOREWORD.5

1 Scope.7

2 Normative references .7

3 Terms, definitions, graphical symbols and acronyms .8

3.1 Terms and definitions .8

3.2 Graphical symbols.9

3.3 Acronyms .11

4 Measurement methods .11
4.1 General .11
4.2 Cabling configurations and applicable test methods .12
4.3 Overview of uncertainties .12
4.3.1 General .12
4.3.2 Test cords .13
4.3.3 Launch conditions at the connection to the cabling under test .13
4.3.4 Optical source .13
4.3.5 Output power reference .13
4.3.6 Received power reference .14
5 Apparatus.14
5.1 General .14
5.2 Light source .14
5.2.1 Stability .14
5.2.2 Spectral characteristics .14
5.2.3 Launch cord .14
5.3 Receive or tail cord .15
5.4 Substitution/dummy cord .15
5.5 Power meter – LSPM methods only .15
5.6 OTDR apparatus .15
5.7 Connector end-face cleaning and inspection equipment .16
5.8 Adapters .16
6 Procedures.16
6.1 General .16
6.2 Common procedures .17

6.2.1 Care of the test cords .17
6.2.2 Make reference measurements (LSPM methods only) .17
6.2.3 Inspect and clean the ends of the fibres in the cabling.17
6.2.4 Make the measurements.17
6.2.5 Make the calculations .17
6.3 Calibration.17
6.4 Safety .17
7 Calculations .17
8 Documentation .18
8.1 Information for each test.18
8.2 Information to be available .18
Annex A (normative) One-cord reference method.19
Annex B (normative) Three-cord reference method .21

61280-4-1 © IEC:2009(E) – 3 –
Annex C (normative) Two-cord reference method .23

Annex D (normative) Optical time domain reflectometer.26

Annex E (normative) Requirements for the source characteristics for multimode

measurement.32

Annex F (informative) Measurement uncertainty examples.35

Annex G (informative) OTDR configuration information .44

Annex H (informative) Test cord insertion loss verification .53

Bibliography.61

Figure 1a – Socket and plug assembly.10
Figure 1b – Connector set (plug, adapter, plug) .10
Figure 1c – Light source .10
Figure 1d – Power meter.10
Figure 1 – Connector symbols .10
Figure 2 – Symbol for cabling under test.10
Figure 3 – OTDR schematic .16
Figure A.1 − Reference measurement.20
Figure A.2 − Test measurement .20
Figure B.1 − Reference measurement.22
Figure B.2 − Test measurement .22
Figure C.1 − Reference measurement.24
Figure C.2 − Test measurement.24
Figure C.3 – Test measurement for plug-socket style connectors.24
Figure D.1 − Test measurement for Method D.27
Figure D.2 − Location of the cabling under test ports .28
Figure D.3 − Graphic construction of F and F .29
1 2
Figure D.4 − Graphic construction of F , F , F and F .30
1 11 12 2
Figure E.1 – Encircled flux template example.33
Figure F.1 – Initial power measurement .37
Figure F.2 – Verification of reference grade connection .38
Figure F.3 – Two offset splices .38

Figure F.4 – Five offset splices .38
Figure F.5 – EF centred .40
Figure F.6 – EF underfilling.40
Figure F.7 – EF overfilling.41
Figure F.8 – L1 loss with mandrel .41
Figure F.9 – L1 loss with mandrel and mode conditioner.42
Figure F.10 – L2 loss (adjusted) with mandrel.42
Figure F.11 – L2 loss (adjusted) with mandrel and mode conditioning.42
Figure F.12 – L3 loss (adjusted) with mandrel.43
Figure F.13 – L3 loss (adjusted) with mandrel and mode conditioning.43
Figure G.1 − Splice and macro bend attenuation measurement.47
Figure G.2 − Attenuation measurement with high reflection connectors.48

– 4 – 61280-4-1 © IEC:2009(E)
Figure G.3 − Attenuation measurement of a short length cabling.49

Figure G.4 − OTDR trace with ghost .50

Figure G.5 − Cursors positioning.51

Figure H.1 − Obtaining reference power level P .54
Figure H.2 − Obtaining power level P .55
Figure H.3 − Obtaining reference power level P .56
Figure H.4 − Obtaining power level P .56

Figure H.5 − Obtaining reference power level P .57
Figure H.6 − Obtaining power level .57
Figure H.7 − Obtaining reference power level P .58
Figure H.8 − Obtaining power leve
...

IEC 61280-4-1 ®
Edition 2.0 2009-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Fibre-optic communication subsystem test procedures –
Part 4-1: Installed cable plant – Multimode attenuation measurement

Procédures d'essai des sous-systèmes de télécommunication
à fibres optiques –
Partie 4-1: Installations câblées – Mesure de l'affaiblissement en multimodal

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.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
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publication, utilisez les coordonnées ci-après ou contactez le Comité national de la CEI de votre pays de résidence.

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CH-1211 Geneva 20
Switzerland
Email: [e-mail]
Web: www.iec.ch
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 corrigenda or an amendment might have been published.
ƒ Catalogue of IEC publications: www.iec.ch/searchpub
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in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical
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IEC 61280-4-1 ®
Edition 2.0 2009-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Fibre-optic communication subsystem test procedures –
Part 4-1: Installed cable plant – Multimode attenuation measurement

Procédures d'essai des sous-systèmes de télécommunication
à fibres optiques –
Partie 4-1: Installations câblées – Mesure de l'affaiblissement en multimodal

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XB
CODE PRIX
ICS 33.180.01 ISBN 978-2-88912-046-8
– 2 – 61280-4-1 © IEC:2009
CONTENTS
FOREWORD.5

1 Scope.7

2 Normative references .7

3 Terms, definitions, graphical symbols and acronyms .8

3.1 Terms and definitions .8

3.2 Graphical symbols.9

3.3 Acronyms .11

4 Measurement methods .11
4.1 General .11
4.2 Cabling configurations and applicable test methods .12
4.3 Overview of uncertainties .12
4.3.1 General .12
4.3.2 Test cords .13
4.3.3 Launch conditions at the connection to the cabling under test .13
4.3.4 Optical source .13
4.3.5 Output power reference .13
4.3.6 Received power reference .14
5 Apparatus.14
5.1 General .14
5.2 Light source .14
5.2.1 Stability .14
5.2.2 Spectral characteristics .14
5.2.3 Launch cord .14
5.3 Receive or tail cord .15
5.4 Substitution/dummy cord .15
5.5 Power meter – LSPM methods only .15
5.6 OTDR apparatus .15
5.7 Connector end-face cleaning and inspection equipment .16
5.8 Adapters .16
6 Procedures.16
6.1 General .16
6.2 Common procedures .17

6.2.1 Care of the test cords .17
6.2.2 Make reference measurements (LSPM methods only) .17
6.2.3 Inspect and clean the ends of the fibres in the cabling.17
6.2.4 Make the measurements.17
6.2.5 Make the calculations .17
6.3 Calibration.17
6.4 Safety .17
7 Calculations .17
8 Documentation .18
8.1 Information for each test.18
8.2 Information to be available .18
Annex A (normative) One-cord reference method.19
Annex B (normative) Three-cord reference method .21

61280-4-1 © IEC:2009 – 3 –
Annex C (normative) Two-cord reference method .23

Annex D (normative) Optical time domain reflectometer.26

Annex E (normative) Requirements for the source characteristics for multimode

measurement .32

Annex F (informative) Measurement uncertainty examples.35

Annex G (informative) OTDR configuration information .44

Annex H (informative) Test cord insertion loss verification .53

Bibliography.61

Figure 1a – Socket and plug assembly.10
Figure 1b – Connector set (plug, adapter, plug) .10
Figure 1c – Light source .10
Figure 1d – Power meter.10
Figure 1 – Connector symbols .10
Figure 2 – Symbol for cabling under test.10
Figure 3 – OTDR schematic .16
Figure A.1 − Reference measurement.20
Figure A.2 − Test measurement .20
Figure B.1 − Reference measurement.22
Figure B.2 − Test measurement .22
Figure C.1 − Reference measurement.24
Figure C.2 − Test measurement.24
Figure C.3 – Test measurement for plug-socket style connectors.24
Figure D.1 − Test measurement for Method D.27
Figure D.2 − Location of the cabling under test ports .28
Figure D.3 − Graphic construction of F and F .29
1 2
Figure D.4 − Graphic construction of F , F , F and F .30
1 11 12 2
Figure E.1 – Encircled flux template example.33
Figure F.1 – Initial power measurement .37
Figure F.2 – Verification of reference grade connection .38
Figure F.3 – Two offset splices .38

Figure F.4 – Five offset splices .
...