Optical fibres - Part 2: Product specifications - General

IEC 60793-2:2019 is available as IEC 60793-2:2019 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 60793-2:2019 contains the general specifications for both multimode and single-mode optical fibres. Sectional specifications for each of the four categories of multimode fibres: A1, A2, A3, and A4 (part of the multimode fibre class A) contain requirements specific to each category. Sectional specifications for each of the three single-mode fibre classes, B, C and D contain requirements common to each class. Each sectional specification includes family specifications (in normative annexes) that contain requirements for the applicable category or sub-categories. These sub-categories are distinguished on the basis of different fibre types or applications. The requirements of this document apply to all classes. Each sectional specification contains the requirements that are common to all the family specifications that are within it. These common requirements are copied to the family specification for ease of reference. Tests or measurement methods are defined for each specified attribute. Where possible, these definitions are by reference to an IEC International Standard (see IEC 60793-1 series) – otherwise the test or measurement method is outlined in the relevant sectional specification. This ninth edition cancels and replaces the eighth edition published in 2015. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- introduction of the revised fibre designations for most A1 sub-category fibres and all class B single-mode fibres;
- addition of the new fibre model (A1-OM5) defined for A1 category;
- addition of class D polarization maintaining fibres.
Keywords: specifications for both multimode and single-mode optical fibres

Fibres optiques - Partie 2: Spécifications de produits - Généralités

IEC 60793-2:2019 est disponible sous forme de IEC 60793-2:2019 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.
L'IEC 60793-2:2019 contient les spécifications générales applicables à la fois aux fibres optiques unimodales et multimodales. Les spécifications intermédiaires pour chacune des catégories des quatre fibres multimodales: A1, A2, A3 et A4 (parties de la classe de fibres multimodales A) contiennent des exigences spécifiques à chaque catégorie. Les spécifications intermédiaires pour chacune des trois classes de fibres unimodales, B, C et D, contiennent des exigences communes à chaque classe. Chaque spécification intermédiaire inclut des spécifications de famille (dans les annexes normatives) qui contiennent des exigences pour la catégorie ou les sous-catégories applicables. La distinction entre ces différentes sous-catégories se fonde sur les différents types de fibres ou les différentes applications. Les exigences du présent document s'appliquent à toutes les classes. Chaque spécification intermédiaire contient les exigences qui sont communes à toutes les spécifications de famille qu'elle regroupe. Ces exigences communes sont reprises dans la spécification de famille pour qu'il soit plus facile de s'y référer. Les essais ou les méthodes de mesure sont définis pour chaque attribut spécifié. Dans la mesure du possible, ces définitions se font par référence à une Norme internationale de l'IEC (voir série IEC 60793-1). Si ce n'est pas le cas, l'essai ou la méthode de mesure est indiqué dans la spécification intermédiaire correspondante. Cette neuvième édition annule et remplace la huitième édition parue en 2015. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- introduction des désignations révisées de la plupart des fibres de la sous-catégorie A1 et de toutes les fibres unimodales de la classe B;
- ajout du nouveau modèle de fibre (A1-OM5) défini pour la catégorie A1;
- ajout des fibres de maintien de la polarisation de classe D.
Mots-clés : spécifications applicables à la fois aux fibres optiques unimodales et multimodales

General Information

Status
Published
Publication Date
14-Nov-2019
Technical Committee
Current Stage
PPUB - Publication issued
Completion Date
15-Nov-2019
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IEC 60793-2
Edition 9.0 2019-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Optical fibres –
Part 2: Product specifications – General
Fibres optiques –
Partie 2: Spécifications de produits – Généralités
IEC 60793-2:2019-11(en-fr)
---------------------- Page: 1 ----------------------
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IEC 60793-2
Edition 9.0 2019-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Optical fibres –
Part 2: Product specifications – General
Fibres optiques –
Partie 2: Spécifications de produits – Généralités
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.10 ISBN 978-2-8322-7600-6

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 60793-2:2019 © IEC 2019
CONTENTS

FOREWORD ........................................................................................................................... 3

1 Scope .............................................................................................................................. 5

2 Normative references ...................................................................................................... 6

3 Terms and definitions ...................................................................................................... 6

4 Quality assurance ............................................................................................................ 7

5 Construction of optical fibres ........................................................................................... 7

5.1 Class A – Multimode fibres ..................................................................................... 7

5.2 Class B – Single-mode fibres .................................................................................. 9

5.3 Class C – Single-mode fibres for intraconnection .................................................. 10

5.4 Class D – Polarization-maintaining fibres .............................................................. 11

6 General requirements .................................................................................................... 11

6.1 Coating ................................................................................................................. 11

6.2 Interface with the coating ...................................................................................... 11

6.3 Colours of the coating ........................................................................................... 12

Annex A (normative) Existing multimode fibres .................................................................... 13

Annex B (normative) Existing single-mode fibres ................................................................. 14

B.1 Existing single-mode fibres ................................................................................... 14

B.2 Existing fibres for intraconnection ......................................................................... 15

B.3 Existing polarization-maintaining fibres ................................................................. 15

Bibliography .......................................................................................................................... 16

Table 1 – Sectional specifications ........................................................................................... 5

Table 2 – Main categories of multimode fibres ........................................................................ 8

Table 3 – Sub-categories of multimode fibres ......................................................................... 8

Table 4 – Categories of glass core/glass clad single-mode fibres .......................................... 10

Table 5 – Categories of glass core/glass clad single-mode fibres for intraconnection ............ 11

Table 6 – Categories of glass core/glass clad polarization-maintaining fibres ........................ 11

Table A.1 – Existing multimode fibres ................................................................................... 13

Table B.1 – Existing single-mode fibres ................................................................................ 14

Table B.2 – Existing fibres for intraconnection ...................................................................... 15

Table B.3 – Existing polarization-maintaining fibres .............................................................. 15

---------------------- Page: 4 ----------------------
IEC 60793-2:2019 © IEC 2019 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL FIBRES –
Part 2: Product specifications –
General
FOREWORD

1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

all national electrotechnical committees (IEC National Committees). The object of IEC is to promote

international co-operation on all questions concerning standardization in the electrical and electronic fields. To

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Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested

in the subject dealt with may participate in this preparatory work. International, governmental and non-

governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely

with the International Organization for Standardization (ISO) in accordance with conditions determined by

agreement between the two organizations.

2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

consensus of opinion on the relevant subjects since each technical committee has representation from all

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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.

9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of

patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 60793-2 has been prepared by subcommittee 86A: Fibres and

cables, of IEC technical committee 86: Fibre optics.

This ninth edition cancels and replaces the eighth edition published in 2015. This edition

constitutes a technical revision.

This edition includes the following significant technical changes with respect to the previous

edition:

a) introduction of the revised fibre designations for most A1 sub-category fibres and all

class B single-mode fibres;
b) addition of the new fibre model (A1-OM5) defined for A1 category;
c) addition of class D polarization maintaining fibres.
---------------------- Page: 5 ----------------------
– 4 – IEC 60793-2:2019 © IEC 2019

This document is to be read in conjunction with those parts of the IEC 60793-1 series that

address individual measurements and tests for attributes of optical fibres.
The text of this International Standard is based on the following documents:
FDIS Report on voting
86A/1964/FDIS 86A/1974/RVD

Full information on the voting for the approval of this International Standard can be found in

the report on voting indicated in the above table.

This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all the parts in the IEC 60793 series, published under the general title Optical fibres,

can be found on the IEC website.

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to

the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
---------------------- Page: 6 ----------------------
IEC 60793-2:2019 © IEC 2019 – 5 –
OPTICAL FIBRES –
Part 2: Product specifications –
General
1 Scope

This part of IEC 60793 contains the general specifications for both multimode and single-

mode optical fibres.

Sectional specifications for each of the four categories of multimode fibres: A1, A2, A3, and

A4 (part of the multimode fibre class A) contain requirements specific to each category.

Sectional specifications for each of the three single-mode fibre classes, B, C and D contain

requirements common to each class.

Each sectional specification includes family specifications (in normative annexes) that contain

requirements for the applicable category or sub-categories. These sub-categories are

distinguished on the basis of different fibre types or applications.
The requirements of this document apply to all classes.

Each sectional specification contains the requirements that are common to all the family

specifications that are within it. These common requirements are copied to the family

specification for ease of reference.

Tests or measurement methods are defined for each specified attribute. Where possible,

these definitions are by reference to an IEC International Standard (see IEC 60793-1 series) –

otherwise the test or measurement method is outlined in the relevant sectional specification.

Table 1 defines the sectional specifications. The relevant family specifications are defined

within the sectional specifications as normative annexes (see Tables 2 to 5).
Annexes A and B summarize the existing fibre specifications.
Table 1 – Sectional specifications
Document ID Fibre Cladding Core material Index profile
category/class material
IEC 60793-2-10 A1 multimode Glass Glass Graded
IEC 60793-2-20 A2 multimode Glass Glass Quasi-step or step
IEC 60793-2-30 A3 multimode Plastic Glass Step or graded (under
consideration)
IEC 60793-2-40 A4 multimode Plastic Plastic Step, multi-step or
graded
IEC 60793-2-50 B single-mode Glass Glass Not applicable
IEC 60793-2-60 C single-mode Glass Glass Not applicable
IEC 60793-2-70 D polarization- Glass Glass Not applicable
maintaining
---------------------- Page: 7 ----------------------
– 6 – IEC 60793-2:2019 © IEC 2019
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.
IEC 60304, Standard colours for insulation for low-frequency cables and wires

IEC 60793-1 (all parts), Optical fibres – Part 1: Measurement methods and test procedures

IEC 60793-2-10:2019, Optical fibres – Part 2-10: Product specifications – Sectional

specification for category A1 multimode fibres

IEC 60793-2-20:2015, Optical fibres – Part 2-20: Product specifications – Sectional

specification for category A2 multimode fibres

IEC 60793-2-30:2015, Optical fibres – Part 2-30: Product specifications – Sectional

specification for category A3 multimode fibres

IEC 60793-2-40:2015, Optical fibres – Part 2-40: Product specifications – Sectional

specification for category A4 multimode fibres

IEC 60793-2-50:2018, Optical fibres – Part 2-50: Product specifications – Sectional

specification for class B single-mode fibres

IEC 60793-2-60:2008, Optical fibres – Part 2-60: Product specifications – Sectional

specification for category C single-mode intraconnection fibres

IEC 60793-2-70:2017, Optical fibres – Part 2-70: Product specifications – Sectional

specification for polarization-maintaining fibres
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following

addresses:
• ISO Online browsing platform: available at https://www.iso.org/obp
• IEC Electropedia: available at http://www.electropedia.org/
3.1
multimode fibre

optical fibre in the core of which the radiation of two or more bound modes can propagate at

the wavelength of interest
[SOURCE: IEC 60050-731:1991, 731-02-03]
3.2
single-mode fibre

optical fibre in which the radiation of only one bound mode can propagate at the wavelength

of interest
[SOURCE: IEC 60050-731:1991, 731-02-02, modified – Note deleted.]
---------------------- Page: 8 ----------------------
IEC 60793-2:2019 © IEC 2019 – 7 –
3.3
core

central region of an optical fibre through which most of the optical power is transmitted

[SOURCE: IEC 60050-731:1991, 731-02-04]
3.4
cladding
dielectric material of an optical fibre surrounding the core
[SOURCE: IEC 60050-731:1991, 731-02-05]
3.5
primary coating

thin coating applied directly to the cladding, usually at the time of the fibre drawing, in one or

more layers, to preserve integrity of the cladding surface

Note 1 to entry A secondary coating may be applied directly to the primary coating of one or more fibres, to

reinforce the protection of the optical fibre during handling and cabling.

[SOURCE: IEC 60050-731:1991, 731-02-57, modified – The wording "usually at the time of

the fibre drawing, in one or more layers," and Note 1 have been added.]
3.6
fibre buffer

material or assembly of materials used to protect the optical fibre against physical damage

[SOURCE: IEC 60050-731:1991, 731-02-56]
3.7
coloured coating

thin coating applied on the primary coating or on the secondary coating in order to make each

fibre distinguishable by its colour
3.8
coloured buffer

buffer applied on the primary coating and/or secondary coating in order to make each fibre

distinguishable by its colour
4 Quality assurance

It is the responsibility of the supplier to establish quality assurance by quality control

procedures which ensures that the product meets the requirements of this document and the

related sectional specifications and family specifications. It is not intended that a complete

testing programme be carried out on every length of fibre. When the customer wishes to

specify acceptance tests or other quality procedures, it is essential that an agreement be

reached between the supplier and the customer at the time of ordering.
5 Construction of optical fibres
5.1 Class A – Multimode fibres

The main fibre categories are based on g, the refractive index profile parameter, see Table 2.

The normalized index profile is expressed as:
---------------------- Page: 9 ----------------------
– 8 – IEC 60793-2:2019 © IEC 2019
δx 1−x
( ) (1)
where
nx −n 1
( ) ()
δx = (2)
( )
nn01−
( ) ()
0≤≤ra is the normalized radial position; (3)
x= ( )
a is the core radius;
n(x) is the refractive index at normalized position x.
Table 2 – Main categories of multimode fibres
Category Material Type Limits
A1 Glass core/glass cladding Graded index fibre 1 ≤ g ˂ 3
A2 Glass core/glass cladding Step and quasi-step index fibre
3 ≤ g ˂ ∞
Step index fibre or
A3 Glass core/plastic cladding 10 ≤ g ˂ ∞
graded index fibre (under 1 ≤ g ≤ 3
consideration)

A4 Plastic core/plastic cladding Step, multi-step, or graded index fibre 1 ≤ g ˂ ∞

NOTE Attention is drawn to the index profile as stated in the detail specification. The fibre category is

determined on the basis of the material type and the g value which best fits the normalized refractive index

profile, falling within the category defined above.

A further differentiation of sub-categories (and models) inside the main categories is given in

Table 3.
Table 3 – Sub-categories of multimode fibres
Category Sub-category Model Nominal Nominal Nominal Nominal
core cladding coating numerical
diameter diameter diameter aperture
(NA )
µm µm µm
A1-OM2 A1-OM2a (traditional 50 125 245 0,20
macrobend loss)
A1-OM2b (enhanced
macrobend loss)
A1-OM3 A1-OM3a (traditional
macrobend loss)
A1-OM3b (enhanced
macrobend loss)
A1-OM4 A1-OM4a (traditional
macrobend loss)
A1-OM4b (enhanced
macrobend loss)
A1-OM5 A1-OM5a (traditional
macrobend loss)
A1-OM5b (enhanced
macrobend loss)
A1-OM1 62,5 125 245 0,275
---------------------- Page: 10 ----------------------
IEC 60793-2:2019 © IEC 2019 – 9 –
Category Sub-category Model Nominal Nominal Nominal Nominal
core cladding coating numerical
diameter diameter diameter aperture
(NA )
µm µm µm
A1d 100 140 245 0,26 or 0,29
A2a 100 140 NS 0,23 or 0,26
A2b 200 240 NS 0,23 or 0,26
A2c 200 280 NS 0,23 or 0,26
A3a 200 300 900 0,40
A3b 200 380 600 0,40
A3c 200 230 500 0,40
A3d 200 230 500 0,35
A3e 200 230 500 0,37
A3f 50 230 500 0,20
A3g 62,5 230 500 0,275
A4a A4a.1 NS 1 000 NA (A4a.1): 0,50
A4a.2 (A4a.2): 0,485
A4b NS 750 NA 0,50
A4c NS 500 NA 0,50
A4d NS 1 000 NA 0,30
A4e ≥ 500 750 NA 0,25
A4f 200 490 NA 0,19
A4g 120 490 NA 0,19
A4h 62,5 245 NA 0,19
NOTE 1 NA = not applicable; NS = not specified.

NOTE 2 All five A1-OMx sub-categories indicated differ in bandwidth (or DMD) requirements.

NOTE 3 Most A1 sub-categories have been changed in terms of fibre designation, starting from

IEC 60793-2-10:2019 (edition 7). See Table 1 of IEC 60793-2-10:2019 for cross-references to former fibre

designations.
5.2 Class B – Single-mode fibres
The categories of single-mode fibres currently in use are given in Table 4.
---------------------- Page: 11 ----------------------
– 10 – IEC 60793-2:2019 © IEC 2019
Table 4 – Categories of glass core/glass clad single-mode fibres
Category Type Description
B-652 Dispersion Dispersion unshifted single-mode fibre.
unshifted
Two sub-categories are recognized:
B-652.B is optimised for use in the 1 310 nm region but can be used in
the 1 550 nm and 1 625 nm regions. Depending on link length and bit
rates, dispersion may need accommodation in the 1 550 nm region.
B-652.D can be used over the extended wavelength range from 1 260 nm
up to 1 625 nm. Chromatic dispersion in this band may impose
requirements either on the maximum link length or the need for
accommodation.

B-653 Dispersion This dispersion-shifted single-mode fibre is optimised for single-channel

shifted transmission in the 1 550 nm region. Multiple channels can only be
transmitted if care is taken to avoid the effects of four-wave mixing by, for
example, moderating the power levels or appropriate spacing or
placement of the channels.
Two sub-categories are recognized (B-653.A and B-653.B) differing in
chromatic dispersion characteristics.

B-654 Cut-off shifted This category of dispersion unshifted single-mode fibre is optimised for

low loss in the 1 550 nm region.
Five sub-categories are recognized (B-654.A, B-654.B, B-654.C, B-654.D
and B-654.E) differing in chromatic dispersion and mode field
characteristics.

B-655 Non-zero This dispersion-shifted single-mode fibre is optimised for multiple channel

dispersion-shifted transmission in the 1 550 nm region. The dispersion coefficient is required

to be non-zero throughout the band from 1 530 nm to 1 565 nm, but may
be either positive or negative. Depending on the dispersion
characteristics, multiple channel transmission may be possible at bands
either above or below the normal 1 550 nm region.
Three sub-categories are recognized (B-655.C, B-655.D and B-655.E),
differing in chromatic dispersion characteristics.

B-656 Wideband non- This wideband non-zero dispersion-shifted single-mode fibre is optimised

zero dispersion- for multiple channel transmission in the wavelength range of 1 460 nm to

shifted 1 625 nm with the positive value of the chromatic dispersion coefficient
that is greater than some non-zero value. This fibre can be used for both
CWDM and DWDM systems throughout the wavelength region between
1 460 nm and 1 625 nm.

B-657 Bending loss This category of single-mode fibre is optimised for improved bending

insensitive performance.
Four sub-categories are recognized:
B-657.A1 and B-657.A2 fibres are a subset of category B-652.D fibres
and therefore are compliant with B-652.D fibres and have the same
transmission properties. Sub-category B-657.A1 fibres are appropriate for
a minimum bend radius of 10 mm; sub-category B-657.A2 fibres for a
minimum bend radius of 7,5 mm.
B-657.B2 and B-657.B3 fibres are intended to be used for restricted
distances (less than 1 000 m) at the end of access networks, in particular
inside buildings or near buildings (e.g. outside building riser cabling).
Application length of B-657.B fibre, however, depends on the deployment
strategy of each network operator.
Sub-category B-657.B fibres are not necessarily compliant with category
B-652.D fibres in terms of chromatic dispersion coefficient specifications.
These fibres, however, are system compatible with B-657.A (and B-652.D)
fibres in access networks.
Sub-category B-657.B2 fibres are appropriate for a minimum bend radius
of 7,5 mm; sub category B-657.B3 fibres for a minimum bend radius of
5 mm.

NOTE The Class B categories have been changed in fibre designation, starting from IEC 60793-2-50:2018

(edition 6). See Table 1 of IEC 60793-2-50:2018 for cross-references to former fibre designations.

5.3 Class C – Single-mode fibres for intraconnection

The categories of single-mode fibres for intraconnection currently in use are given in Table 5.

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Table 5 – Categories of glass core/glass clad single-mode fibres for intraconnection

Category Type Description

C1 Single-mode intraconnection fibre This category of single-mode fibre is optimised for precision

suitable for use with any class B glass geometry and improved macrobending, and generally

single-mode fibre at wavelengths having lower fibre cut-off wavelength compared to that of

from 1 260 nm to B-652.B fibres.
1 625 nm.

C2 Single-mode intraconnection fibre This category of single-mode fibre with reduced mode field

suitable for use from 1 260 nm to diameter is optimised for loss performance in the 1 310 nm

1 360 nm. region.

Single-mode intraconnection fibre This category of single-mode fibre with reduced mode field

suitable for use from 1 530 nm to diameter is optimised for loss performance in the 1 550 nm

1 625 nm. region.

Single-mode intraconnection fibre This single-mode intraconnection fibre is intended to support

suitable for use at 980 nm. 980 nm transmissions.

NOTE All four categories indicated have sub-categories based on 125 µm and 80 µm cladding diameter.

5.4 Class D – Polarization-maintaining fibres

The categories of polarization-maintaining fibres currently in use are given in Table 6.

Table 6 – Categories of glass core/glass clad polarization-maintaining fibres
Category Type Description

D1 Polarization-maintaining fibre This category of polarization-maintaining fibre is

suitable for use at 980 nm optimised for polarization-maintain
...

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