EN 61746-2:2011

Calibration of optical time-domain reflectometers (OTDR) - Part 2: OTDR for multimode fibres

IEC 61746-2:2010(E) provides procedures for calibrating multimode optical time domain reflectometers (OTDR). It covers OTDR measurement errors and uncertainties. The test of the laser(s) source modal condition is included as an optional measurement. This standard does not cover correction of the OTDR response.

Kalibrierung optischer Rückstreumessgeräte (OTDR) - Teil 2: OTDR für Mehrmodenfasern

Etalonnage des réflectomètres optiques dans le domaine temporel (OTDR) - Partie 2: OTDR pour fibres multimodales

L'IEC 61746-2:2010 fournit des procédures destinées à l'étalonnage des réflectomètres optiques dans le domaine de temps pour fibres multimodales (OTDR). Elle traite des erreurs de mesure et incertitudes de l'OTDR. L'essai des conditions modales des sources laser est une mesure facultative. La présente norme ne couvre pas la correction de la réponse de l'OTDR. Mots clés: l'étalonnage des réflectomètres optiques dans le domaine de temps pour fibres multimodales (OTDR).

Kalibriranje optičnih reflektometrov v časovnem prostoru (OTDR) - 2. del: OTDR za večrodovna vlakna (IEC 61746-2:2010)

Ta del IEC 61746 podaja postopke kalibriranja večrodovnih optičnih časovnih reflektometrov (OTDR). Zajema napake merjenja OTDR in negotovosti. Preskus pogoja modalnega vira laserjev je vključen kot mogoče merjenje. Ta standard ne zajema popravka odziva OTDR.

General Information

• Status: Published
• Publication Date: 20-Jan-2011
• Withdrawal Date: 01-Jan-2014
• ICS: 33.180.01 - Fibre optic systems in general
• Technical Committee: CLC/SR 86 - Fibre optics
• Drafting Committee: IEC/TC 86 - IEC_TC_86
• Parallel Committee: IEC/TC 86 - IEC_TC_86
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 21-Jan-2011
• Completion Date: 21-Jan-2011
• Ref Project: SIST EN 61746-2:2011 - Calibration of Optical Time-Domain Reflectometers (OTDR) - Part 2: OTDR for multimode fibres (IEC 61746-2:2010)

Relations

• Corrected By: EN 61746-2:2011/AC:2014 - Calibration of optical time-domain reflectometers (OTDR) - Part 2: OTDR for multimode fibres
• Effective Date: 23-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
01-marec-2011
.DOLEULUDQMHRSWLþQLKUHIOHNWRPHWURYYþDVRYQHPSURVWRUX27'5GHO27'5]D
YHþURGRYQDYODNQD,(&
Calibration of Optical Time-Domain Reflectometers (OTDR) - Part 2: OTDR for
multimode fibres (IEC 61746-2:2010)
Kalibrierung optischer Rückstreumessgeräte (OTDR) - Teil 2: OTDR für
Mehrmodenfasern (IEC 61746-2:2010)
Etalonnage des réflectomètres optiques dans le domaine de temps (OTDR) - Partie 2:
OTDR pour les fibres multimodes (CEI 61746-2:2010)
Ta slovenski standard je istoveten z: EN 61746-2:2011
ICS:
17.180.30 2SWLþQLPHULOQLLQVWUXPHQWL Optical measuring
instruments
33.180.99 'UXJDRSUHPD]DRSWLþQD Other fibre optic equipment
YODNQD
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 61746-2
NORME EUROPÉENNE
January 2011
EUROPÄISCHE NORM
ICS 33.180.01 Supersedes EN 61746:2005 (partially)

English version
Calibration of optical time-domain reflectometers (OTDR) -
Part 2: OTDR for multimode fibres
(IEC 61746-2:2010)
Etalonnage des réflectomètres optiques Kalibrierung optischer
dans le domaine de temps (OTDR) - Rückstreumessgeräte (OTDR) -
Partie 2: OTDR pour les fibres multimodes Teil 2: OTDR für Mehrmodenfasern
(CEI 61746-2:2010) (IEC 61746-2:2010)

This European Standard was approved by CENELEC on 2011-01-02. CENELEC 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 Central Secretariat or to any CENELEC 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 CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2011 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61746-2:2011 E
Foreword
The text of document 86/336/CDV, future edition 1 of IEC 61746-2, prepared by IEC TC 86, Fibre optics,
was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61746-2 on
2011-01-02.
This European Standard partially supersedes EN 61746:2005.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent
rights.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2011-10-02
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2014-01-02
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 61746-2:2010 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
[2] IEC 60793-1-1 NOTE  Harmonized as EN 60793-1-1.
[3] IEC 60793-1-40 NOTE  Harmonized as EN 60793-1-40.
[4] IEC 60794-1-2 NOTE  Harmonized as EN 60794-1-2.
[5] IEC 60825-1 NOTE  Harmonized as EN 60825-1.
[6] IEC 60825-2 NOTE  Harmonized as EN 60825-2.
[7] IEC 61280-1-3 NOTE  Harmonized as EN 61280-1-3.
[8] IEC 61280-2-10 NOTE  Harmonized as EN 61280-2-10.
[9] IEC 61300-3-6 NOTE  Harmonized as EN 61300-3-6.
__________
- 3 - EN 61746-2:2011
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application 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.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year

IEC 60793-2-10 - Optical fibres - EN 60793-2-10 -
Part 2-10: Product specifications - Sectional
specification for category A1 multimode fibres

IEC 60793-2-50 - Optical fibres - EN 60793-2-50 -
Part 2-50: Product specifications - Sectional
specification for class B single-mode fibres

IEC 61280-1-4 - Fibre optic communication subsystem test EN 61280-1-4 -
procedures -
Part 1-4: General communication subsystems
- Light source encircled flux measurement
method
IEC 61280-4-1 - Fibre optic communication subsystem test EN 61280-4-1 -
procedures -
Part 4-1: Installed cable plant - Multimode
attenuation measurement
IEC 61745 - End-face image analysis procedure for the - -
calibration of optical fibre geometry test sets

ISO/IEC 17025 - General requirements for the competence of EN ISO/IEC 17025 -
testing and calibration laboratories

IEC 61746-2 ®
Edition 1.0 2010-06
INTERNATIONAL
STANDARD
Calibration of optical time-domain reflectometers (OTDR) –
Part 2: OTDR for multimode fibres

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
X
ICS 33.180.01 ISBN 978-2-88912-026-0
– 2 – 61746-2 © IEC:2010(E)
CONTENTS
FOREWORD.4
INTRODUCTION.6
1 Scope.7
2 Normative references.7
3 Terms, definitions and symbols .7
4 Preparation for calibration.13
4.1 Organization .13
4.2 Traceability.13
4.3 Preparation.13
4.4 Test conditions .13
4.5 Documentation .13
5 Distance calibration – General .14
5.1 General .14
5.2 Location deviation model .14
5.3 Using the calibration results.16
5.4 Measuring fibre length .17
6 Distance calibration methods .17
6.1 General .17
6.2 External source method .17
6.2.1 Short description and advantage .17
6.2.2 Equipment .17
6.2.3 Calibration of the equipment .19
6.2.4 Measurement procedure .20
6.2.5 Calculations and results .20
6.2.6 Uncertainties .21
6.3 Concatenated fibre method (using multimode fibres) .23
6.3.1 Short description and advantages .23
6.3.2 Equipment .23
6.3.3 Measurement procedures.24
6.3.4 Calculations and results .24
6.3.5 Uncertainties .25
6.4 Recirculating delay line method.26
6.4.1 Short description and advantages .26
6.4.2 Equipment .27
6.4.3 Measurement procedure .28
6.4.4 Calculations and results .28
6.4.5 Uncertainties .29
7 Vertical scale calibration – General .30
7.1 General .30
7.2 Loss difference calibration .31
7.2.1 Determination of the displayed power level F.31
7.2.2 Development of a test plan.31
7.3 Characterization of the OTDR source near field .33
7.3.1 Objectives and references .33
7.3.2 Procedure.33
8 Loss difference calibration method.34

61746-2 © IEC:2010(E) – 3 –
8.1 General .34
8.2 Long fibre method.34
8.2.1 Short description.34
8.2.2 Equipment .34
8.2.3 Measurement procedure .36
8.2.4 Calculation and results.36
Annex A (normative) Multimode recirculating delay line for distance calibration.37
Annex B (normative) Mathematical basis .41
Bibliography .44

Figure 1 – Definition of attenuation dead zone .8
Figure 2 – Representation of the location deviation ΔL(L).15
Figure 3 – Equipment for calibration of the distance scale – External source method .18
Figure 4 – Set-up for calibrating the system insertion delay.19
Figure 5 – Concatenated fibres used for calibration of the distance scale.23
Figure 6 – Distance calibration with a recirculating delay line .27
Figure 7 – OTDR trace produced by recirculating delay line .28
Figure 8 – Determining the reference level and the displayed power level .31
Figure 9 – Region A, the recommended region for loss measurement samples .32
Figure 10 – Possible placement of sample points within region A .33
Figure 11 – Linearity measurement with a long fibre .35
Figure 12 – Placing the beginning of section D outside the attenuation dead zone .35
Figure A.1 – Recirculating delay line.37
Figure A.2 – Measurement set-up fo
...