IEC 60793-2-10:2015

IEC 60793-2-10 ®
Edition 5.0 2015-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Optical fibres –
Part 2-10: Product specifications – Sectional specification for category A1
multimode fibres
Fibres optiques –
Partie 2-10: Spécifications de produits – Spécification intermédiaire pour les
fibres multimodales de catégorie A1

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IEC 60793-2-10 ®
Edition 5.0 2015-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Optical fibres –
Part 2-10: Product specifications – Sectional specification for category A1

multimode fibres
Fibres optiques –
Partie 2-10: Spécifications de produits – Spécification intermédiaire pour les

fibres multimodales de catégorie A1

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.10 ISBN 978-2-8322-3006-0

– 2 – IEC 60793-2-10:2015 © IEC 2015
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms, definitions and abbreviations . 9
3.1 Terms and definitions . 9
3.2 Abbreviations . 9
4 Specifications . 9
4.1 Dimensional requirements . 9
4.2 Mechanical requirements . 10
4.3 Transmission requirements . 11
4.4 Environmental requirements . 13
4.4.1 General . 13
4.4.2 Mechanical environmental requirements (common to all fibres in
category A1) . 14
4.4.3 Transmission environmental requirements . 15
Annex A (normative) Family specifications for A1a multimode fibres . 16
A.1 General . 16
A.2 Dimensional requirements . 16
A.3 Mechanical requirements . 17
A.4 Transmission requirements . 17
A.5 Environmental requirements . 18
Annex B (normative) Family specifications for A1b multimode fibres . 19
General . 19
B.1
B.2 Dimensional requirements . 19
B.3 Mechanical requirements . 19
B.4 Transmission requirements . 19
B.5 Environmental requirements . 20
Annex C (normative) Family specifications for A1d multimode fibres . 21
C.1 General . 21
C.2 Dimensional requirements . 21
C.3 Mechanical requirements . 21
C.4 Transmission requirements . 21
C.5 Environmental requirements . 22
Annex D (normative) Fibre differential mode delay (DMD) and calculated effective
modal bandwidth (EMBc) requirements . 23
D.1 A1a.2 fibre DMD requirements . 23
D.1.1 General . 23
D.1.2 DMD templates . 23
D.1.3 DMD interval masks . 24
D.2 A1a.2 fibre EMB requirements . 25
c
D.2.1 General . 25
D.2.2 Calculated effective bandwidth . 25
D.3 A1a.3 DMD requirements . 27
D.3.1 General . 27
D.3.2 DMD templates . 27
D.3.3 DMD interval masks . 28

D.4 A1a.3 fibre EMB requirements . 28
c
D.4.1 General . 28
D.4.2 Calculated effective bandwidth . 28
Annex E (informative) Modal bandwidth considerations and transmitter requirements . 29
E.1 Background. 29
E.2 Transmitter encircled flux (EF) and centre wavelength requirements . 29
E.2.1 Encircled flux . 29
E.2.2 Centre wavelength . 29
E.3 EMB . 30
Annex F (informative) Bandwidth nomenclature explanation . 31
Annex G (informative) Preliminary indications for items needing further study . 32
G.1 Effective modal bandwidth (EMB) at 1 300 nm . 32
G.2 Scaling of EMB with DMD . 32
Annex H (informative) Applications supported by A1 fibres . 34
H.1 Internationally standardised applications . 34
H.2 Used commercial bandwidth specifications . 34
H.3 Cross reference of fibre types in this standard and ISO/IEC 11801 . 35
H.4 Reference documents . 35
Annex I (informative) 1-Gigabit, 10-Gigabit, 40-Gigabit and 100-Gigabit Ethernet
applications . 36
Bibliography . 40

Figure 1 – Relation between bandwidths at 850 nm and 1 300 nm . 13
Figure D.1 – DMD template requirements . 24

Table 1 – Dimensional attributes and measurement methods . 10
Table 2 – Dimensional requirements common to category A1 fibres . 10
Table 3 – Additional dimensional attributes required in family specifications . 10
Table 4 – Mechanical attributes and measurement methods . 11
Table 5 – Mechanical requirements common to category A1 fibres . 11
Table 6 – Transmission attributes and measurement methods . 12
Table 7 – Additional transmission attributes required in family specifications . 12
Table 8 – Environmental exposure tests . 13
Table 9 – Attributes measured for environmental tests . 14
Table 10 – Strip force for environmental tests . 14
Table 11 – Tensile strength for environmental tests . 14
Table 12 – Stress corrosion susceptibility for environmental tests . 15
Table 13 – Change in attenuation for environmental tests . 15
Table A.1 – Dimensional requirements specific to A1a fibres . 16
Table A.2 – Mechanical requirements specific to A1a fibres . 17
Table A.3 – Transmission requirements specific to A1a fibres . 18
Table B.1 – Dimensional requirements specific to A1b fibres . 19
Table B.2 – Mechanical requirements specific to A1b fibres . 19
Table B.3 – Transmission requirements specific to A1b fibres . 20
Table C.1 – Dimensional requirements specific to A1d fibres . 21

– 4 – IEC 60793-2-10:2015 © IEC 2015
Table C.2 – Mechanical requirements specific to A1d fibres . 21
Table C.3 – Transmission requirements specific to A1d fibres. 22
Table D.1 – DMD templates for A1a.2 fibres . 23
Table D.2 – DMD interval masks for A1a.2 fibres . 25
Table D.3 – DMD weightings (1 of 2) . 26
Table D.4 – DMD templates for A1a.3 fibres . 28
Table D.5 – DMD interval masks for A1a.3 fibres . 28
Table F.1 – Bandwidth nomenclature explanation . 31
Table H.1 – Some internationally standardised applications supported by A1a and A1b
fibres . 34
Table H.2 – Typically used commercial bandwidth specifications for A1a and A1b
graded-index multimode fibres . 35
Table H.3 – Cross reference between this standard and ISO/IEC 11801 . 35
Table I.1 – Summary of 1 Gb/s, 10 Gb/s, 40 Gb/s and 100 Gb/s Ethernet requirements
and capabilities (1 of 3) . 37

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL FIBRES –
Part 2-10: Product specifications –
Sectional specification for category A1 multimode fibres

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
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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6) All users should ensure that they have the latest edition of this publication.
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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 60793-2-10 has been prepared by subcommittee 86A: Fibres and
cables, of IEC technical committee 86: Fibre optics.
This fifth edition cancels and replaces the fourth edition published in 2011. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) addition of enhanced macrobending multimode fibres A1a.1b, A1a.2b and A1a.3b;
b) inclusion of the specified test wavelength and specimen length for core diameter (CD),
numerical aperture (NA), differential mode delay (DMD) and threshold values for CD and
NA;
c) addition of a specimen length for 850 nm bandwidth of A1a and A1b fibres.

– 6 – IEC 60793-2-10:2015 © IEC 2015
The text of this standard is based on the following documents:
CDV Report on voting
86A/1631/CDV 86A/1664/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all 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 publication will remain unchanged until
the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
OPTICAL FIBRES –
Part 2-10: Product specifications –
Sectional specification for category A1 multimode fibres

1 Scope
This part of IEC 60793 is applicable to optical fibre types A1a, A1b, and A1d. These fibres are
used or can be incorporated in information transmission equipment and optical fibre cables.
Type A1a applies to 50/125 µm graded index fibre. Three bandwidth grades are defined as
A1a.1, A1a.2 and A1a.3. Each of these bandwidth grades is defined for two levels of
macrobend loss performance that are distinguished by “a” or “b” suffix. Those with suffix “a”
are specified to meet traditional macrobend loss performance levels. Those with suffix “b” are
specified to meet enhanced macrobend loss (i.e. lower loss) performance levels.
Type A1b applies to 62,5/125 µm graded index fibre and A1d applies to 100/140 µm graded
index fibre.
Other applications include, but are not restricted to, the following: short reach, high bit-rate
systems in telephony, distribution and local networks carrying data, voice and/or video
services; on-premises intra-building and inter-building fibre installations including data
centres, local area networks (LANs), storage area networks (SANs), private branch
exchanges (PBXs), video, various multiplexing uses, outside telephone cable plant use, and
miscellaneous related uses.
Three types of requirements apply to these fibres:
• general requirements, as defined in IEC 60793-2;
• specific requirements common to the category A1 multimode fibres covered in this
standard and which are given in Clause 3;
• particular requirements applicable to individual fibre types or specific applications, which
are defined in the normative family specification annexes.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60793-1 (all parts), Optical fibres – Part 1: Measurement methods and test procedures
IEC 60793-1-20, Optical fibres – Part 1-20: Measurement methods and test procedures –
Fibre geometry
IEC 60793-1-21, Optical fibres – Part 1-21: Measurement methods and test procedures –
Coating geometry
IEC 60793-1-22, Optical fibres – Part 1-22: Measurement methods and test procedures –
Length measurement
– 8 – IEC 60793-2-10:2015 © IEC 2015
IEC 60793-1-30, Optical fibres – Part 1-30: Measurement methods and test procedures –
Fibre proof test
IEC 60793-1-31, Optical fibres – Part 1-31: Measurement methods and test procedures –
Tensile strength
IEC 60793-1-32, Optical fibres – Part 1-32: Measurement methods and test procedures –
Coating strippability
IEC 60793-1-33, Optical fibres – Part 1-33: Measurement methods and test procedures –
Stress corrosion susceptibility
IEC 60793-1-34, Optical fibres – Part 1-34: Measurement methods and test procedures –
Fibre curl
IEC 60793-1-40, Optical fibres – Part 1-40: Measurement methods and test procedures –
Attenuation
IEC 60793-1-41, Optical fibres – Part 1-41: Measurement methods and test procedures –
Bandwidth
IEC 60793-1-42, Optical fibres – Part 1-42: Measurement methods and test procedures –
Chromatic dispersion
IEC 60793-1-43, Optical fibres – Part 1-43: Measurement methods and test procedures –
Numerical aperture measurement
IEC 60793-1-46, Optical fibres – Part 1-46: Measurement methods and test procedures –
Monitoring of changes in optical transmittance
IEC 60793-1-47, Optical fibres – Part 1-47: Measurement methods and test procedures –
Macrobending loss
IEC 60793-1-49, Optical fibres – Part 1-49: Measurement methods and test procedures –
Differential mode delay
IEC 60793-1-50, Optical fibres – Part 1-50: Measurement methods and test procedures –
Damp heat (steady state) tests
IEC 60793-1-51, Optical fibres – Part 1-51: Measurement methods and test procedures –Dry
heat (steady state) tests
IEC 60793-1-52, Optical fibres – Part 1-52: Measurement methods and test procedures –
Change of temperature tests
IEC 60793-1-53, Optical fibres – Part 1-53: Measurement methods and test procedures –
Water immersion tests
IEC 60793-2:2011, Optical fibres – Part 2: Product specifications – General
IEC 61280-4-1, Fibre-optic communication subsystem test procedures – Part 4-1: Installed
cable plant – Multimode attenuation measurement
IEC TR 61931, Fibre optic – Terminology

3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60793-2, the
IEC 60793-1 series and IEC 61931 apply.
3.2 Abbreviations
CD core diameter
CPR coupled power ratio
DMD differential mode delay
EF encircled flux
EMB effective modal bandwidth
EMBc calculated effective modal bandwidth
LAN local area network
MMF multimode fibre
NA numerical aperture
OFL overfilled launch
OMBc overfilled launch modal bandwidth calculated from differential mode delay (also
known as OFLc)
PBX private branch exchange
PMD physical medium dependent
ROFL radial overfilled launch
SAN storage area network
4 Specifications
NOTE 1 The fibre consists of a glass core with a graded index profile and a glass cladding in accordance with
IEC 60793-2:2011, 5.1.
NOTE 2 The term “glass” usually refers to material consisting of non-metallic oxides.
4.1 Dimensional requirements
Dimensional attributes and measurement methods are given in Table 1.
Requirements common to all fibres in category A1 are indicated in Table 2.
Table 3 lists additional attributes that shall be specified by each family specification.

– 10 – IEC 60793-2-10:2015 © IEC 2015
Table 1 – Dimensional attributes and measurement methods
Attribute Measurement method
Cladding diameter IEC 60793-1-20

a, b
Core diameter IEC 60793-1-20
Cladding non-circularity IEC 60793-1-20
Core non-circularity IEC 60793-1-20
Core-cladding concentricity error IEC 60793-1-20
Primary coating diameter IEC 60793-1-21
Primary coating non-circularity IEC 60793-1-21
Primary coating-cladding concentricity error IEC 60793-1-21
Fibre length IEC 60793-1-22
a
Core diameter is specified at 850 nm ± 10 nm with a test specimen length of 2,0 m ± 0,2 m and a threshold
value, k of 0,025 for A1 fibres except A1a.1b/2b/3b fibres.
CORE
b
Core diameter is specified at 850 nm ± 10 nm with a test specimen length of 100 m ± 5 % and a threshold
value, k of 0,025 for A1a.1b/2b/3b fibres.
CORE
Table 2 – Dimensional requirements common to category A1 fibres
Attribute Unit Limit
Core non-circularity %
≤ 6
b
Primary coating diameter – uncoloured µm 245 ± 10
b
Primary coating diameter – coloured µm 250 ± 15
Primary coating-cladding concentricity error
µm ≤ 12,5
a
Fibre length km
a
Length requirements vary and should be agreed between supplier and customer.
b
The above limits on primary coating diameter are most commonly used in telecommunications cables. There
are other applications, which use other primary coating diameters, several of which are listed below.
Alternative nominal primary coating diameters and tolerance (µm):
400 ± 40
500 ± 50
700 ± 100
900 ± 100
Table 3 – Additional dimensional attributes required in family specifications
Attribute
Cladding diameter
Cladding non-circularity
Core diameter
Core-cladding concentricity error

4.2 Mechanical requirements
Mechanical attributes and measurement methods are given in Table 4.
Requirements common to all fibres in category A1 are in Table 5.

Table 4 – Mechanical attributes and measurement methods
Attribute Test method
Proof test IEC 60793-1-30
Tensile strength IEC 60793-1-31
Primary coating strippability IEC 60793-1-32
Stress corrosion susceptibility IEC 60793-1-33
Fibre curl IEC 60793-1-34
Table 5 – Mechanical requirements common to category A1 fibres
Attribute Unit Limit
a
Proof stress level GPa
≥ 0,69
b
Average strip force N
1,0 ≤ F ≤ 5,0
avg
b
Peak strip force N
1,0 ≤ F ≤ 8,9
peak
Tensile strength (median) for 0,5m GPa ≥ 3,8
specimen length
Stress corrosion susceptibility constant n ≥ 18
d
a
The proof test value of 0,69 GPa equals about 1 % strain or about 8,8 N force,
for A1a and A1b fibres. For the relation between these different units, see
IEC TR 62048.
b
Either average strip force or peak strip force, which are defined in the test
procedure, may be specified by agreement between supplier and customer.

4.3 Transmission requirements
Transmission attributes and measurement methods are given in Table 6.
Table 7 lists additional attributes that shall be specified by each family specification.

– 12 – IEC 60793-2-10:2015 © IEC 2015
Table 6 – Transmission attributes and measurement methods
Attribute Measurement
method
Attenuation coefficient IEC 60793-1-40
a,b
Modal bandwidth IEC 60793-1-41

c,d
Numerical aperture IEC 60793-1-43
Chromatic dispersion IEC 60793-1-42
Change of optical transmission IEC 60793-1-46
Macrobending loss IEC 60793-1-47

e
Differential mode delay IEC 60793-1-49
a
For modal bandwidth either overfilled launch (OFL) or overfilled launch modal
bandwidth calculated from differential mode delay (OMBc) can be used. OMBc
is the reference test method for A1a fibres at 850 nm.
b
850 nm modal bandwidth is specified at 850 nm ± 10 nm with a test specimen
length of 1 000 m ± 5 % for A1a fibres.
c
Numerical aperture is specified at 850 nm ± 10 nm with a test specimen length
of 2 m ± 0,2 m and a threshold value, k of 0,05 for A1 fibres except
NA
A1a.1b/2b/3b fibres.
d
Numerical aperture is specified at 850 nm ± 10 nm with a test specimen length
of 100 m ± 5 % and a threshold value, k of 0,05 for A1a.1b/2b/3b fibres.
NA
e
Differential mode delay is specified at 850 nm ± 10 nm with a test specimen
length of 1 000 m ± 5 % for A1a fibres.

Specification compliance of chromatic dispersion can be assured by compliance to the
numerical aperture specification.
Table 7 – Additional transmission attributes
required in family specifications
Attribute
Attenuation coefficient
Modal bandwidth
Chromatic dispersion
Numerical aperture
Macrobending loss
For attenuation coefficient and modal bandwidth, the family specification contains ranges of
specifiable values instead of fixed limits. The actual values of the maximum attenuation
coefficient and minimum modal bandwidth, at both 850 nm and 1 300 nm (or just at one of
these wavelengths) are to be agreed between supplier and customer. For commercial
purposes, the modal bandwidth is linearly normalized to 1 km.
For guidance purposes on bandwidth, Table H.1 shows a number of internationally
standardised applications supported by A1 fibres, and Table H.2 gives a (limited) number of
frequently used commercial bandwidth specifications for A1a and A1b fibres.
The indicated maximum attenuation values apply to uncabled optical fibres; for the maximum
cabled attenuation values, reference is made to IEC 60794-1-1, which can be used in
conjunction with this standard.
Remarks on the specification of modal bandwidth:
Care should be taken in writing dual wavelength bandwidth specifications. For category A1
fibres, the bandwidth at 850 nm may be related to the bandwidth at 1 300 nm in a way shown

in Figure 1, depending on the refractive index parameter, g, (see IEC 60793-2:2011, 5.1). The
shaded region under the curve of Figure 1 can be defined as the dual window area. In this
area, regions X, Y, and Z are examples of where a fibre manufacturer may choose to optimise
the process. That is, centre the production at 850 nm, 1 300 nm, or between these two
wavelengths.
Due to this optimisation of the manufacturing process, there will be combinations of bandwidth
that are not possible. For example, it is practically impossible to produce a fibre with the
maximum of both indicated bandwidth ranges (e.g. 800 MHz⋅km/1 000 MHz⋅km for A1b
multimode fibres).
X
Y
Z
Normalised bandwidth at 1 300 nm (MHz⋅km)
IEC
Figure 1 – Relation between bandwidths at 850 nm and 1 300 nm
4.4 Environmental requirements
4.4.1 General
Environmental exposure tests and measurement methods are documented in two forms:
• Relevant environmental attributes and test procedures are given in Table 8.
• Measurements of a particular mechanical or transmission attribute that may change on the
application of the environment are listed in Table 9.
Table 8 – Environmental exposure tests
Environmental exposure Test
Damp heat IEC 60793-1-50
Dry heat IEC 60793-1-51
Change of temperature IEC 60793-1-52
Water immersion IEC 60793-1-53

Normalised bandwidth at 850 nm (MHz • km)

– 14 – IEC 60793-2-10:2015 © IEC 2015
Table 9 – Attributes measured for environmental tests
Attribute Measurement method
Change in optical transmission IEC 60793-1-46
Attenuation IEC 60793-1-40
Strip force IEC 60793-1-32
Tensile strength IEC 60793-1-31
Stress corrosion susceptibility IEC 60793-1-33

These tests are normally conducted periodically as type-tests for a fibre and coating design.
Unless otherwise indicated, the recovery period allowed between the completion of the
environmental exposure and performing the attribute measurements shall be as stated in the
particular environmental test method.
4.4.2 Mechanical environmental requirements (common to all fibres in category A1)
4.4.2.1 General
These tests are, in practice, the most severe requirements amongst the environments defined
in Table 8.
Tables 10, 11, and 12 give the prescriptions for strip force, tensile strength and stress
corrosion susceptibility respectively.
4.4.2.2 Strip force
The following attributes shall be verified following removal of the fibre from the particular
environment.
Table 10 – Strip force for environmental tests
Environment Average strip force (N) Peak strip force (N)
Damp heat
1,0 ≤ F ≤ 5,0 1,0 ≤ F ≤ 8,9
avg peak
Water immersion 1,0 ≤ F ≤ 5,0 1,0 ≤ F ≤ 8,9
avg peak
4.4.2.3 Tensile strength
The following attribute shall be verified following removal of the fibre from the environment.
Table 11 – Tensile strength for environmental tests
Environment Median tensile strength 15th percentile tensile strength
specimen length: 0,5 m specimen length: 0,5 m
GPa GPa
Damp heat
≥ 3,03 ≥ 2,76
NOTE These requirements do not apply to hermetically coated fibre

4.4.2.4 Stress corrosion susceptibility
The following attribute shall be verified following removal of the fibre from the environment.

Table 12 – Stress corrosion susceptibility for environmental tests
Environment Stress corrosion susceptibility constant, n
d
Damp heat
≥ 18
NOTE This requirement does not apply to hermetically coated fibre.

4.4.3 Transmission environmental requirements
Change in attenuation from the initial value shall be less than the values in Table 13.
Attenuation shall be measured periodically during the entire exposure to each environment
and after removal.
Table 13 – Change in attenuation for environmental tests
Environment Wavelength Attenuation increase
nm dB/km
Damp heat 850 ≤ 0,20
1 300 ≤ 0,20
Dry heat 850
≤ 0,20
1 300 ≤ 0,20
Change of temperature 850 ≤ 0,20
1 300
≤ 0,20
Water immersion 850
≤ 0,20
1 300 ≤ 0,20
– 16 – IEC 60793-2-10:2015 © IEC 2015
Annex A
(normative)
Family specifications for A1a multimode fibres
A.1 General
Annex A contains particular requirements applicable to A1a fibres. Common requirements,
repeated here for ease of reference from the sectional specification, are noted by an entry in
the “Reference” column. Relevant notes from the sectional specification are not repeated but
SS
“ ”
indicated with a superscript .
Type A1a is a 50/125 µm graded index fibre. Three bandwidth grades are defined as models
A1a.1, A1a.2, and A1a.3. All three are specified using overfilled bandwidth metrics, while
types A1a.2 and A1a.3 also apply differential mode delay metrics to specify two bandwidth
grades of 850 nm laser-optimised 50/125 µm fibres.
Each of these three bandwidth grades is also specified for two levels of macrobend loss
performance that are distinguished by “a” or “b” suffix. Those with suffix “a” (i.e. A1a.1a,
A1a.2a and A1a.3a) are specified to meet traditional macrobend loss performance levels.
Those with suffix “b” (i.e. A1a.1b, A1a.2b and A1a.3b) are specified to meet enhanced
macrobend loss (i.e. lower loss) performance levels.
The nomenclature for the A1a family establishes a coding hierarchy that permits designation
of fibres with increasing specificity. For example, purchase orders for A1a fibres may be filled
by any of the models specified in Annex A, while purchase orders for A1a.2 may be filled by
A1a.2a or A1a.2b. As a result, where specifications and descriptions apply to all models at
lower hierarchical levels, only the common root is stated.
The dimensional, mechanical and environmental requirements are common to all and
specified in Tables A.1 and A.2. The common and distinguishing transmission requirements
are specified in Table A.3.
A.2 Dimensional requirements
Table A.1 contains dimensional requirements specific to A1a fibres.
Table A.1 – Dimensional requirements specific to A1a fibres
Attribute Unit Limit Reference
Cladding diameter
µm 125 ± 1
Cladding non-circularity % ≤ 1
Core diameter 4.1 (Table 1)
µm 50 ± 2,5
Core-cladding concentricity error
µm ≤ 2
Core non-circularity % ≤ 6 4.1
Primary coating diameter – uncoloured 4.1
µm 245 ± 10
Primary coating diameter – coloured 4.1
µm 250 ± 15
Primary coating-cladding concentricity error µm ≤ 12,5 4.1
Length km (see 4.1) 4.1 (Table 2)

A.3 Mechanical requirements
Table A.2 contains the mechanical requirements specific to A1a fibres.
Table A.2 – Mechanical requirements specific to A1a fibres
Attribute Unit Limit Reference

SS
Proof stress level GPa ≥ 0,69 4.2

SS
Average strip force N 1,0 ≤ F ≤ 5,0 4.2
avg
SS
Peak strip force N 4.2
1,0 ≤ F ≤ 8,9
peak
A.4 Transmission requirements
Table A.3 contains transmission requirements specific to A1a fibres.

– 18 – IEC 60793-2-10:2015 © IEC 2015
Table A.3 – Transmission requirements specific to A1a fibres
Attribute Unit Limit Reference
Fibre model A1a.1 A1a.2 A1a.3
Maximum attenuation coefficient at dB/km 2,5
850 nm
Maximum attenuation coefficient at dB/km 0,8
1 300 nm
Minimum modal bandwidth-length 500 1 500 3 500 4.3
MHz⋅km
product for overfilled launch at 850 nm (Table 6)
Minimum modal bandwidth-length 500
MHz⋅km
product for overfilled launch at
1 300 nm
Differential mode delay at 850 nm ps/m Not Meet Meet 4.3
specified Clause Clause (Table 6),
D.1 D.3 Annexes
or or D, E, F, G
Clause Clause
D.2 D.4
Numerical aperture Dimensionless 0,20 ± 0,015 4.3
(Table 6)
Maximum Bending Number dB A1a.1a A1a.2a A1a.3a
macrobending radius of turns
a Max at 850 nm / 1 300 nm
loss
37,5 mm 100 0,5 / 0,5
15 mm 2 1,0 / 1,0
Bending Number dB A1a.1b A1a.2b A1a.3b
radius of turns
Max at 850 nm / 1 300 nm
0,5 / 0,5
37,5 mm 100
0,1 / 0,3
15 mm 2
0,2 / 0,5
7,5 mm 2
b
nm
Zero dispersion wavelength, λ 1 295 ≤ λ ≤ 1 340
0 0
Zero dispersion slope, S
ps/nm ⋅km
b
- from 1 295 nm ≤ λ ≤ 1 310 nm ≤ 0,105
b
- from 1 310 nm ≤ λ ≤ 1 340 nm ≤ 0,000 375 (1 590 – λ )
0 0
a
The launch condition for the macrobe
...