oSIST prEN IEC 60794-2-20:2023

SLOVENSKI STANDARD
oSIST prEN IEC 60794-2-20:2023
01-junij-2023
Optični kabli - 2-20. del: Notranji kabli - Skupinska specifikacija za distribucijske
kable z več optičnimi vlakni
Optical fibre cables - Part 2-20: Indoor cables - Family specification for multi-fibre optical
cables
Lichtwellenleiterkabel - Teil 2-20: LWL-Innenkabel - Familienspezifikation für Mehrfaser-
Lichtwellenleiterkabel
Câbles à fibres optiques - Partie 2-20: Câbles intérieurs - Spécification de famille pour
les câbles optiques multifibres
Ta slovenski standard je istoveten z: prEN IEC 60794-2-20:2023
ICS:
33.180.10 (Optična) vlakna in kabli Fibres and cables
oSIST prEN IEC 60794-2-20:2023 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN IEC 60794-2-20:2023

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oSIST prEN IEC 60794-2-20:2023
86A/2310/CDV
COMMITTEE DRAFT FOR VOTE (CDV)

PROJECT NUMBER:
IEC 60794-2-20 ED4
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2023-04-07 2023-06-30
SUPERSEDES DOCUMENTS:
86A/2234/CD, 86A/2308/CC

IEC SC 86A : FIBRES AND CABLES
SECRETARIAT: SECRETARY:
France Mr Laurent Gasca
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:


Other TC/SCs are requested to indicate their interest, if
any, in this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.

This document is still under study and subject to change. It should not be used for reference purposes.
Recipients of this document are invited to submit, with their comments, notification of
• any relevant patent rights of which they are aware and to provide supporting documentation,
• any relevant “in some countries” clauses to be included should this proposal proceed. Recipients are
reminded that the enquiry stage is the final stage for submitting "in some countries" clauses. See
AC/22/2007.

TITLE:
Optical fibre cables - Part 2-20: Indoor cables - Family specification for multi-fibre optical
cables

PROPOSED STABILITY DATE: 2027

NOTE FROM TC/SC OFFICERS:


Copyright © 2023 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to
download this electronic file, to make a copy and to print out the content for the sole purpose of preparing National
Committee positions. You may not copy or "mirror" the file or printed version of the document, or any part of it, for
any other purpose without permission in writing from IEC.

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oSIST prEN IEC 60794-2-20:2023
IEC CDV 60794-2-20/Ed4 © IEC:2023 – 2 – 86A/2310/CDV
1 CONTENTS
2 CONTENTS . 2
3 FOREWORD . 4
4 1 Scope . 6
5 2 Normative references . 6
6 3 Terms and definitions . 7
7 4 Construction . 7
8 4.1 General . 7
9 4.2 Optical fibres . 8
10 4.3 Buffer . 8
11 4.4 Ruggedized fibre . 8
12 4.5 Slotted core . 8
13 4.6 Tube . 8
14 4.7 Stranded tube . 8
15 4.8 Ribbon structure . 8
16 4.9 Strength and anti-buckling members. 9
17 4.10 Ripcord . 9
18 4.11 Sheath . 9
19 4.12 Sheath marking . 9
20 4.13 Identification . 9
21 4.14 Examples of cable constructions . 9
22 5 Tests . 9
23 5.1 General . 9
24 5.2 Dimensions . 10
25 The fibre dimensions and tolerances shall be checked in accordance with the test
26 method as specified in IEC 60793-1-20 or IEC 60793-1-21. The diameter of
27 the buffer and of the cable, as well as the thickness of the sheath, shall be
28 measured in accordance with the methods of IEC 60811 201 and IEC 60811-
29 203. . 10
30 5.3 Mechanical requirements . 10
31 5.3.1 Tensile performance . 10
32 5.3.2 Crush . 10
33 5.3.3 Impact . 10
34 5.3.4 Bending . 11
35 5.3.5 Repeated bending . 11
36 5.3.6 Bending under tension . 11
37 5.3.7 Bending at low temperature . 11
38 5.3.8 Flexing . 11
39 5.3.9 Torsion . 11
40 5.3.10 Cable kink . 12
41 5.4 Environmental requirements . 12
42 5.4.1 Temperature cycling . 12
43 3.5 13
44 5.5 Transmission requirements. 13
45 5.5.1 General . 13
46 5.5.2 Single-mode optical fibres . 13
47 5.5.3 Single-mode dispersion unshifted (B-652.B) optical fibre . 13
48 5.5.4 Single-mode dispersion unshifted (B-652.D) optical fibre . 13

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49 5.5.5 Single-mode (B-657.A) optical fibre . 14
50 5.5.6 Single-mode (B-657.B) optical fibre . 14
51 5.5.7 Multimode optical fibres . 14
52 5.5.8 Multimode (A1-OM1 to A1-OM5) optical fibres . 14
53 5.6 Fire performance . 15
54
Annex A (informative) Examples of cable constructions . 16
55 Annex B (informative) Family specification for multi-fibre optical cables – Blank detail
56 specification and minimum requirements . 21
57 B.1 Blank detail specification . 21
58 B.1.1 Cable description . 21
59 B.1.2 Cable element . 22
60 B.1.3 Cable construction . 22
61 B.1.4 Installation and operating conditions . 24
62 Mechanical and environmental tests . 24
B.1.5
63 B.2 Cables subject to the MICE environmental classification (ISO/IEC 11801-1
64 and related standards) . 25
65 Bibliography . 26
66
67 Figure A.1 – Example of cross-section of a 12 fibre cable . 16
68
Figure A.2 – Example of cross-section of a 36 fibre cable . 16
69 Figure A.3 – Example of cross-section of a 6 fibre break-out cable . 17
70
Figure A.4 – Example of cross-section of a 24 fibre break-out cable . 17
71 Figure A.5 – Example of cross-section of a slotted core type indoor cable with 4 fibre
72 ribbons . 18
73 Figure A.6 – Example of cross-section of an SZ (reverse oscillating lay) slotted core
74 type indoor cable with 2 fibre ribbons . 18
75 Figure A.7 – Example of cross-section of an SZ (reverse oscillating lay) slotted core
76
type indoor cable with 4 fibre bundles . 19
77 19
78
Figure A.8 – Example of multi-fibre unitube cable . 19
79 Figure A.9 – Example of multi-fibre cable . 20
80
Figure A.10 – Example of a retractable (micro-module) cable . 20
81 Table 1 – Dimensions of buffered fibres . 8
82
Table 2 – Sample values for temperature cycling . 12
83 Table 3 – Common single-mode optical fibre requirements . 13
84
Table 4 – Cabled fibre attenuation requirements for B-652.B optical fibre . 13
85 Table 5 – Cabled fibre attenuation requirements for B-652.D optical fibre . 14
86
Table 6 – Cabled fibre attenuation requirements for B-657.A optical fibre . 14
87 Table 7 – Cabled fibre attenuation requirements for B-657.B optical fibre . 14
88
Table 8 – Common multimode optical fibre requirements . 14
89 Table 9 – Cabled fibre attenuation requirements for A1-OM1 to A1-OM5 optical fibres . 15
90
Table B.1 – Cable description (1 of 2) . 21
91 Table B.2 – Cable element . 22
92
Table B.3 – Cable construction . 22
93 Table B.4 – Installation and operating conditions . 24
94
Table B.5 – Tests applicable . 24

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95
96 INTERNATIONAL ELECTROTECHNICAL COMMISSION
97 ____________
98
99 OPTICAL FIBRE CABLES –
100
101 Part 2-20: Indoor cables –
102 Family specification for multi-fibre optical cables
103
104 FOREWORD
105 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
106 all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
107 co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
108 in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
109 Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
110 preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
111 may participate in this preparatory work. International, governmental and non-governmental organizations liaising
112 with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
113 Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
114 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
115 consensus of opinion on the relevant subjects since each technical committee has representation from all
116 interested IEC National Committees.
117 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
118 Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
119 Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
120 misinterpretation by any end user.
121 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
122 transparently to the maximum extent possible in their national and regional publications. Any divergence between
123 any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
124 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
125 assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
126 services carried out by independent certification bodies.
127 6) All users should ensure that they have the latest edition of this publication.
128 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
129 members of its technical committees and IEC National Committees for any personal injury, property damage or
130 other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
131 expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
132 Publications.
133 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
134 indispensable for the correct application of this publication.
135 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
136 rights. IEC shall not be held responsible for identifying any or all such patent rights.
137 International Standard IEC 60794-2-20 has been prepared by sub-committee 86A: Fibres and
138 cables, of IEC technical committee 86: Fibre optics.
139 This fourth edition cancels and replaces the third edition published in 2013 and constitutes a
140 technical revision.
141 This edition includes the following significant technical changes with respect to the previous
142 edition:
143 a) update of the normative references;
144 b) review update of parameters and requirements for mechanical tests and environmental
145 tests, mainataining alignment with additional relevant standards in the IEC 60794-2 series
146 c) cabled fibre attenuation requirements have been added
147 d) additional cable design examples have been added

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oSIST prEN IEC 60794-2-20:2023
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148 This International Standard is to be used in conjunction with IEC 60794-1-1, IEC 60794-1-2,
149 IEC 60794-1-21, IEC 60794-1-22, IEC 60794-1-23 =IEC 60794-2.
150 The text of this standard is based on the following documents:
FDIS Report on voting
86A/xxxx/FDIS 86A/xxxx/RVD
151
152 Full information on the voting for the approval of this standard can be found in the report on
153 voting indicated in the above table.
154 The language used for the development of this International Standard is English.
155 This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
156 accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
157 at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
158 described in greater detail at www.iec.ch/publications.
159 A list of all parts of IEC 60794 series, published under the general title Optical fibre cables, can
160 be found on the IEC website.
161 The committee has decided that the contents of this publication will remain unchanged until the
162 stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data related to
163 the specific publication. At this date, the publication will be
164 • reconfirmed,
165 • withdrawn,
166 • replaced by a revised edition, or
167 • amended.
168
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.
169
170
171

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172 OPTICAL FIBRE CABLES –
173
174 Part 2-20: Indoor cables –
175 Family specification for multi-fibre optical cables
176
177
178
179 1 Scope
180 This part of IEC 60794 is a family specification covering multi-fibre optical cables for indoor
181 use. The requirements of the sectional specification IEC 60794-2 are applicable to cables
182 covered by this standard. Annex B contains a Blank Detail Specification and general guidance
183 in case the cables are intended to be used in installation governed by the MICE table of ISO/IEC
184 11801-1) .
185 2 Normative references
186 The following documents are referred to in the text in such a way that some or all of their content
187 constitutes requirements of this document. For dated references, only the edition cited applies.
188 For undated references, the latest edition of the referenced document (including any
189 amendments) applies.
190 NOTE These reference complete the normative references already listed in the generic specifications (IEC 60794-1-
191 1 and IEC 60794-1-2).
192 IEC 60304, Standard colours for insulation for low-frequency cables and wires
193 IEC 60793-1-20, Optical fibres – Part 1-20: Measurement methods and test procedures – Fibre
194 geometry
195 IEC 60793-1-21, Optical fibres – Part 1-21: Measurement methods and test procedures –
196 Coating geometry
197 IEC 60793-1-40, Optical fibres – Part 1-40: Attenuation measurement methods
198 IEC 60793-1-44, Optical fibres - Part 1-44: Measurement methods and test procedures - Cut-
199 off wavelength
200 IEC 60793-1-46, Optical fibres - Part 1-46: Measurement methods and test procedures -
201 Monitoring of changes in optical transmittanceIEC 60793-2-10, Optical fibres – Part 2-10:
202 Product specifications – Sectional specification for category A1 multimode fibres
203 IEC 60793-2-50, Optical fibres – Part 2-50: Product specifications – Sectional specification for
204 class B single-mode fibres
205 IEC 60794-1-1, Optical fibre cables – Part 1-1: Generic specification – General
206 IEC 60794-1-2, Optical fibre cables – Part 1-2: Generic specification – Basic optical cable test
207 procedures
208 IEC 60794-1-3, Optical fibre cables - Part 1-3: Generic specification - Optical cable elements
209 IEC 60794-1-21, Optical fibre cables – Part 1-21: Generic specification – Basic optical cable
210 test procedures – Mechanical test methods

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211 IEC 60794-1-22, Optical fibre cables – Part 1-22: Generic specification – Basic optical cable
212 test procedures – Environmental test methods
213 IEC 60794-1-23, Optical fibre cables – Part 1-23: Generic specification – Basic optical cable
214 test procedures – Cable element test methods
215 IEC 60794-1-31, Optical fibre cables – Part 1-31: Generic specification - Optical cable elements
216 - Optical fibre ribbon
217 IEC 60794-2, Optical fibre cables – Part 2: Indoor cables – Sectional specification
218 IEC 60811-202, Electric and optical fibre cables – Test methods for non-metallic materials –
219 Part 202: General tests – Measurement of thickness of non-metallic sheath
220 IEC 60811-203, Electric and optical fibre cables – Test methods for non-metallic materials –
221 Part 203: General tests – Measurement of overall dimensions.
222 ISO/IEC 11801-1, Information technology – Generic cabling for customer premises
223
224 3 Terms and definitions
225 No terms and definitions are listed in this document.
226 For the purposes of this document, the terms and definitions given in IEC 60794-1-1 apply.
227 ISO and IEC maintain terminological databases for use in standardization at the following
228 addresses:
229
230 • IEC Electropedia: available at http://www.electropedia.org/
231 • ISO Online browsing platform: available at http://www.iso.org/obp
232
233 4 Construction
234 4.1 General
235 In addition to the constructional requirements in IEC 60794-2, the following considerations
236 apply to multi-fibre indoor cables.
237 The cable shall be designed and manufactured for an expected operating lifetime of at least 15
238 years. In this context, the attenuation at the operational wavelength(s) of the optical fibres
239 contained in the installed cable shall not exceed values specified in Clause 4.5, Transmission
240 requirements. The materials in the cable shall not present a health or environmental hazard
241 within its intended use.
242 Optical elements may comprise any of the cable elements described in clauses 3.3 to 3.8 below
243 or in IEC 60794-1-3.
244 There shall be no fibre splice in a delivery length unless otherwise agreed by customer and
245 supplier.
246 It shall be possible to identify each individual fibre throughout the length of the cable.

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247 4.2 Optical fibres
248 Multimode or single-mode optical fibres meeting the requirements of IEC 60793-2-10 sub-categories
249 A1-OM1 to A1-OM5 or IEC 60793-2-50 Categories B-652 and B-657 shall be used.The linear
250 coefficient of optical fibre attenuation and attenuation point discontinuity may be affected by
251 the cable manufacturing process. Maximum values for these optical characteristics shall be as
252 specified in Clause 5.4, Transmission requirements.
253 4.3 Buffer
254 If a buffer is required, it shall consist of one or more layers of inert material. The buffer shall be
255 easily removable. For tight buffers, the buffer and fibre primary coating shall be removable in
256 one operation over a minimum length of 15 mm, depending on customer requirements. For
257 semi-tight buffers, the buffer shall be easily removable over a minimum length of 300 mm. For
258 loose buffers, the buffer shall be easily removable over a length of not less than 1,0 m.Buffer
259 dimensions are shown in Table 1.
260 Table 1 – Dimensions of buffered fibres
261 Buffer type Nominal diameter Tolerances
mm mm
Semi-tight or loose buffer 0,3 to 1,3 ± 0,05
Tight buffer 0,3 to 1,0 ± 0,05
262
263 4.4 Ruggedized fibre
264 Further protection can be provided to tight or semi-tight buffered fibres by surrounding them
265 with non-metallic strength members within a sheath of suitable material.
266 4.5 Slotted core
267 The slotted core is obtained by extruding a suitable material with a defined number of slots,
268 providing helical or SZ (reverse-oscillating lay) configuration along the core. One or more
269 primary coated fibres or optical elements such as ribbons or fibre bundles are located in each
270 slot.
271 4.6 Tube
272 One or more primary coated or buffered fibres or ribbons are packaged (loosely or not) in a
273 tube construction which may be filled. The tube may be reinforced with a composite wall. The
274 polymeric tube may be hard, to provide some crush protection to the fibre bundle or soft to
275 enable easy strippability of the tube without specialized tools.
276 4.7 Stranded tube
277 Multiple tubes, containing one or more primary coated or buffered fibres or ribbons, may be:
278 • stranded around a central member
279 • non-stranded
280 • a number of homogeneous optical tubes stranded using helical or SZ configurations
281
282 For the sake of preserving cable geometry, some tubes may be "filler" or "empty" elements
283 not containing optical fibres.
284 4.8 Ribbon structure
285 Ribbon structures shall conform to IEC 60794-1-31. Fibres shall be arranged to be parallel and
286 formed into ribbons so that the fibres remain parallel and do not cross over.

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287 Partially bonded ribbon structures enable the optical fibre ribbon to be rolled up easily and
288 accommodated very tightly in cables. Unless otherwise specified, each ribbon shall be uniquely
289 identified with a printed legend or by uniquely colouring the reference fibre and/or by colouring
290 the matrix material of the ribbon.
291 4.9 Strength and anti-buckling members
292 The cable shall be designed with sufficient strength members to meet installation and service
293 conditions so that the fibres are not subjected to strain in excess of limits specified in clause
294 4.3.1, Tensile performance.
295 The strength and/or anti-buckling members may be either metallic or non-metallic and may be
296 located in the cable core and/or under the sheath and/or in the sheath.
297 4.10 Ripcord
298 If required, a ripcord may be provided beneath the sheath.
299 4.11 Sheath
300 The cable shall have an overall protective sheath. The cable diameter shall be specified in the
301 relevant blank detail specification (or product) specification.
302 4.12 Sheath marking
303 If required, the cable shall be marked as agreed between customer and supplier.
304 4.13 Identification
305 Optical fibres, buffers and sub-unit sheaths shall be easily and uniquely identifiable through the
306 use of a suitable colour code (i.e. IEC 60304) and/or an easily visible numbering scheme to be
307 agreed between customer and supplier.
308 4.14 Examples of cable constructions
309 Examples of some types of cable construction are shown in Annex A. Other configurations (e.g.
310 multi-layer constructions) are not precluded if they meet the mechanical, en
...