IEC 60794-2-20:2008

IEC 60794-2-20 ®
Edition 2.0 2008-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Optical fibre cables –
Part 2-20: Indoor cables – Family specification for multi-fibre optical distribution
cables
Câbles à fibres optiques –
Partie 2-20: Câbles intérieurs – Spécification de famille pour les câbles de
distribution optiques multifibres

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IEC 60794-2-20 ®
Edition 2.0 2008-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Optical fibre cables –
Part 2-20: Indoor cables – Family specification for multi-fibre optical distribution
cables
Câbles à fibres optiques –
Partie 2-20: Câbles intérieurs – Spécification de famille pour les câbles de
distribution optiques multifibres

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX T
ICS 33.180.01 ISBN 978-2-88912-615-6

– 2 – 60794-2-20  IEC:2008
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Construction . 6
3.1 General . 6
3.2 Optical fibres and primary coating . 7
3.3 Buffer . 7
3.4 Ruggedised fibre . 7
3.5 Slotted core . 7
3.6 Tube. 7
3.7 Stranded tube. 7
3.8 Ribbon structure . 8
3.9 Strength and anti-buckling members . 8
3.10 Ripcord . 8
3.11 Sheath . 8
3.12 Sheath marking . 8
3.13 Identification. 8
3.14 Examples of cable constructions . 8
4 Tests . 8
4.1 Dimensions . 8
4.2 Mechanical requirements . 9
4.2.1 Cable tensile performance . 9
4.2.2 Cable crush . 9
4.2.3 Cable impact . 9
4.2.4 Cable bending . 10
4.2.5 Cable repeated bending . 10
4.2.6 Cable bending under tension . 10
4.2.7 Cable bending at low temperature . 10
4.2.8 Cable flexing . 10
4.2.9 Cable torsion . 10
4.2.10 Cable kink . 11
4.3 Environmental requirements – Temperature cycling . 11
4.4 Transmission requirements . 11
4.5 Fire performance . 11
Annex A (informative) Examples of cable constructions . 13
Annex B (informative) Family specification for multi-fibre optical distribution cables –
Blank detail specification and minimum requirements . 18
Bibliography . 24

Figure A.1 – Example of cross-section of a 12 fibre distribution cable . 13
Figure A.2 – Example of cross-section of a 36 fibre distribution cable . 13
Figure A.3 – Example of cross-section of a 6 fibre break-out cable . 14
Figure A.4 – Example of cross-section of a 24 fibre break-out cable . 14
Figure A.5 – Example of cross-section of a slotted core type indoor cable with 4 fibre
ribbons . 15

60794-2-20  IEC:2008 – 3 –
Figure A.6 – Example of cross-section of an SZ (reverse oscillating lay) slotted core
type indoor cable with 2 fibre ribbons . 15
Figure A.7 – Example of cross-section of an SZ (reverse oscillating lay) slotted core
type indoor cable with 4 fibre bundles . 16
Figure A.8 – Example of multi-fibre unitube cable . 16
Figure A.9 – Example of multi-fibre cable . 17

Table 1 – Dimensions of buffered fibres . 7
Table 2 – Sample temperature cycling values . 11
Table B.1 – Cable description . 18
Table B.2 – Cable element . 19
Table B.3 – Cable construction . 20
Table B.4 – Installation and operating conditions . 20
Table B.5 – Tests applicable . 21
Table B.6 – Specifications for industrial premises installations as defined in
ISO/IEC 24702 . 22

– 4 – 60794-2-20  IEC:2008
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
OPTICAL FIBRE CABLES –
Part 2-20: Indoor cables –
Family specification for multi-fibre optical distribution cables

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,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
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-
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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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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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 60794-2-20 has been prepared by subcommittee 86A: Fibres and
cables, of IEC technical committee 86: Fibre optics.
This second edition cancels and replaces the first edition published in 2003. It constitutes a
technical revision.
The main changes from the previous edition include:
– cable crush to be measured both during and after load;
– cable torsion test length parameter correlated to cable outer diameter;
– cable description and construction blank detail specification annexes;
– MICE environment blank detail specification is addressed in Annex B.
This standard is to be used in conjunction with IEC 60794-1-1 and IEC 60794-1-2, and
IEC 60794-2.
60794-2-20  IEC:2008 – 5 –
This bilingual version, published in 2011-07, corresponds to the English version.
The text of this standard is based on the following documents:
CDV Report on voting
86A/1187/CDV 86A/1221/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.
The French version of this standard has not been voted upon.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of IEC 60794 series, published under the general title Optical fibre cables,
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 web site 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.
– 6 – 60794-2-20  IEC:2008
OPTICAL FIBRE CABLES –
Part 2-20: Indoor cables –
Family specification for multi-fibre optical distribution cables

1 Scope
This part of IEC 60794 is a family specification covering multi-fibre optical distribution cables
for indoor use. The requirements of the sectional specification IEC 60794-2 are applicable to
cables covered by this standard.
Annex B contains requirements that supersede the normal requirements in case the cables
are intended to be used in installation governed by the MICE table of ISO/IEC 24702 (i.e.
industrial premises).
2 Normative references
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.
They complete the normative references already listed in the generic specification
(IEC 60794-1-1, Clause 2, and IEC 60794-1-2, Clause 2).
IEC 60189-1, Low-frequency cables and wires with PVC insulation and PVC sheath – Part 1:
General test and measuring methods
IEC 60304, Standard colours for insulation for low-frequency cables and wires
IEC 60793-2-10, Optical fibres – Part 2-10: Product specifications – Sectional specification for
category A1 multimode fibres
IEC 60793-2-50, Optical fibres – Part 2-50: Product specifications – Sectional specification for
class B single-mode fibres
IEC 60794-2, Optical fibre cables – Part 2: Indoor cables – Sectional specification
IEC 60811-1-4, Common test methods for insulating and sheathing materials of electric
cables – Part 1: Methods for general application – Section four: Tests at low temperature
IEC 62222, Fire performance of communication cables installed in buildings
3 Construction
3.1 General
In addition to the constructional requirements in IEC 60794-2, the following considerations
apply to multi-fibre indoor cables.
The cable shall be designed and manufactured for an expected operating lifetime of at least
15 years. In this context, the attenuation at the operational wavelength(s) of the optical fibres
contained in the installed cable shall not exceed values agreed between customer and

60794-2-20  IEC:2008 – 7 –
supplier. The materials in the cable shall not present a health or environmental hazard within
its intended use.
There shall be no fibre splice in a delivery length unless otherwise agreed by customer and
supplier.
It shall be possible to identify each individual fibre throughout the length of the cable.
3.2 Optical fibres and primary coating
A1 multimode fibres which meet the requirements of IEC 60793-2-10 or B1.1, B1.3, B6_a, and
B6_b single-mode optical fibres which meet the requirements of IEC 60793-2-50 shall be used.
The linear coefficient of optical fibre attenuation and attenuation point discontinuity may be
affected by the cable manufacturing process. Maximum values for these optical
characteristics shall be agreed between customer and supplier.
3.3 Buffer
If a tight or semi-tight (loosely applied) buffer is required, it shall consist of one or more layers
of inert material. The buffer shall be easily removable. For tight buffers, the buffer and fibre
primary coating shall be removable in one operation over a length of 15 mm to 25 mm,
depending on customer requirements. For semi-tight buffers, the buffer shall be easily
removable over a length of 0,3 m to 2,0 m.
Buffer dimensions are shown in Table 1.
Table 1 – Dimensions of buffered fibres
Buffer type Nominal diameter Tolerances
mm mm
Semi-tight buffer 0,3 - 1,3
±0,05
Tight buffer 0,3 - 1,0
±0,05
3.4 Ruggedised fibre
Further protection can be provided to tight or semi-tight secondary coated fibres by
surrounding them with non-metallic strength members within a sheath of suitable material.
3.5 Slotted core
The slotted core is obtained by extruding a suitable material with a defined number of slots,
providing helical or SZ (reverse-oscillating lay) configuration along the core. One or more
primary coated fibres or optical elements such as ribbons or fibre bundles are located in each
slot.
3.6 Tube
One or more primary coated or buffered fibres or ribbons are packaged (loosely or not) in a
tube construction which may be filled. The tube may be reinforced with a composite wall.
3.7 Stranded tube
Multiple tubes, containing one or more primary coated or buffered fibres or ribbons, are
stranded around a central member. For the sake of preserving cable geometry, some tubes
may be "filler" or "empty" elements not containing optical fibres.

– 8 – 60794-2-20  IEC:2008
3.8 Ribbon structure
Ribbon structures shall conform to IEC 60794-3, 6.5 and 8.2.3. Fibres shall be arranged to be
parallel and formed into ribbons so that the fibres remain parallel and do not cross over.
Unless otherwise specified, each ribbon shall be uniquely identified with a printed legend or
by uniquely colouring the reference fibre and/or by colouring the matrix material of the ribbon.
3.9 Strength and anti-buckling members
The cable shall be designed with sufficient strength members to meet installation and service
conditions so that the fibres are not subjected to strain in excess of limits agreed between
customer and supplier.
The strength and/or anti-buckling members may be either metallic or non-metallic and may be
located in the cable core and/or under the sheath and/or in the sheath.
3.10 Ripcord
If required, a ripcord may be provided beneath the sheath.
3.11 Sheath
The cable shall have an overall protective sheath. The cable diameter shall be specified in the
relevant blank detail specification (or product) specification.
3.12 Sheath marking
If required, the cable shall be marked as agreed between the customer and the supplier.
3.13 Identification
Optical fibres, secondary coatings and sub-unit sheaths shall be easily and uniquely
identifiable through the use of a suitable colour code (i.e. IEC 60304) and/or an easily visible
numbering scheme to be agreed between the customer and the supplier.
3.14 Examples of cable constructions
Examples of some main types of cable construction are shown in Annex A. Other
configurations (e.g. multi-layer constructions) are not precluded if they meet the mechanical,
environmental and transmission requirements given in this specification.
4 Tests
Compliance with relevant detail specification requirements shall be verified by carrying out
tests selected from the following subclauses. It is not intended that all tests be carried out; the
frequency of testing shall be agreed between the customer and the supplier.
Unless otherwise specified, all tests shall be carried out at ambient temperature. Attenuation
measurements shall be conducted at the highest specified wavelength.
4.1 Dimensions
The fibre dimensions and tolerances shall be verified in accordance with test method
IEC 60793-1-20, method C or IEC 60793-1-21. The diameter of the buffer and of the cable, as
well as the thickness of the sheath, shall be measured in accordance with the methods of
IEC 60189-1.
60794-2-20  IEC:2008 – 9 –
4.2 Mechanical requirements
Some of the following tests can be performed on a short sample length of cable which is still
an integral part of a longer length. Thus it becomes possible to detect permanent changes in
attenuation within the measurement uncertainty of the equipment used (see 3.8.2,
Assessment of uncertainties in IEC 60794-1-2). The wavelength and maximum value of this
attenuation change shall be agreed between the customer and the supplier.
4.2.1 Cable tensile performance
Method: IEC 60794-1-2-E1A and/or E1B
Diameter of chuck drums
and transfer devices: not smaller than the minimum bending diameter specified
for the cable under load
Velocity of transfer device: either 100 mm/min or 100 N/min
Load and duration: 400 N or the weight of 1 km of cable, whichever is greater,
and for a minimum period of 5 min
Length of sample: sufficient to achieve the desired accuracy of measurement
of attenuation change (typically 300 m) and shall be
agreed between the customer and the supplier
Requirements: for E1A there shall be no change in attenuation after the
test,
for E1B allowed fibre strain to be agreed between supplier
and customer.
There shall be no visible damage to the cable elements
NOTE 1 Fibre strain above 60 % of the proof test of the all-glass fibre while under test load is not recommended.
NOTE 2 For certain applications specifying MICE classification of ISO/IEC 24702 and related standards, different
load and duration values may be agreed between the customer and the supplier.
4.2.2 Cable crush
Method: IEC 60794-1-2-E3
Force during installation: 500 N
Duration during installation: 1 min
Force during operation: ffs
Duration during operation: ffs
Length between test locations: 500 mm
Requirements: no change in attenuation during the operational test and
after the installation test. There shall be no visible damage
to the cable elements
NOTE For certain applications specifying MICE classification of ISO/IEC 24702 and related standards, different
force values may be agreed between the customer and the supplier.
4.2.3 Cable impact
Method: IEC 60794-1-2-E4
Radius of striking surface: 12,5 mm
Impact energy: 1,0 J
Number of impacts: at least 3, each separated by at least 500 mm
Requirements: no fibre breakage
NOTE For certain applications specifying MICE classification of ISO/IEC 24702 and related standards, impact
energy values may be agreed between customer and supplier.

– 10 – 60794-2-20  IEC:2008
4.2.4 Cable bending
Method: IEC 60794-1-2-E11A
Mandrel diameter: 20 times cable diameter
Number of turns per helix: 6
Number of cycles: 10
Requirements: no fibre breakage
NOTE For certain applications specifying MICE classification of ISO/IEC 24702 and related standards, different
mandrel diameter values may be agreed between the customer and the supplier.
4.2.5 Cable repeated bending
Method: IEC 60794-1-2-E6
Bending radius: 20 times cable diameter
Number of cycles: 25
Mass of weights: 4 kg
Requirements: under visual examination without magnification there shall
be no damage to the sheath and to the cable elements
4.2.6 Cable bending under tension
Method: IEC 60794-1-2-E18
Bending radius: 20 times cable diameter
Load: 400 N or weight of 1 km of cable, whichever is greater
Requirements: no change in attenuation after the test, and
there shall be no visible damage to the cable elements
4.2.7 Cable bending at low temperature
Method: IEC 60794-1-2-E11A (see IEC 60811-1-4, Clause 8)
Bending radius: 10 times cable diameter
Test temperature: 0 °C, –10 °C or –15 °C depending on application and
customer requirements
Number of turns per helix: according to Clause 8 of IEC 60811-1-4
Number of cycles: 2
Requirements: in addition to the requirements of Clause 8 of IEC 60811-
1-4, no fibre shall break during the test
4.2.8 Cable flexing
Method: IEC 60794-1-2-E8
Number of cycles: 100
Pulley diameter: 20 times cable diameter
Mass of weights: 2 kg (minimum)
Requirements: no fibre breakage
NOTE For certain applications specifying MICE classification of ISO/IEC 24702 and related standards, different
pulley diameter values may be agreed between the customer and the supplier.
4.2.9 Cable torsion
Method: IEC 60794-1-2-E7
Number of cycles: 10
Distance between fixed and rotation clamp: 125 times cable diameter but not more than 2,0 m
Tension load: 20 N
60794-2-20  IEC:2008 – 11 –
Requirements: no fibre breakage
NOTE For certain applications specifying MICE classification of ISO/IEC 24702 and related standards, different
values for the number of cycles may be agreed between customer and supplier.
4.2.10 Cable kink
Method: IEC 60794-1-2-E10
Minimum loop diameter: 20 times cable diameter
Requirement: no kink shall occur
4.3 Environmental requirements – Temperature cycling
Method: IEC 60794-1-2-F1
Table 2 – Sample temperature cycling values
Low temperature High temperature
T T
A B
a
a) 0 °C +50 °C
a
b)
–5 °C +50 °C
a
c)
–20 °C +60 °C
a
d) –40 °C +75 °C
a
Condition a), b) c) or d) shall be selected depending on
application and customer requirements, for example condition
c) is appropriate for applications to ISO/IEC 11801.

Period: t = sufficient time such that the cable has reached
thermal stability throughout its entire length at the
specified temperature (e.g. 8 h ≤ t ≤ 24 h)
Number of cycles: 2
Length of sample: sufficient to achieve the desired accuracy of measurement
of attenuation
Requirements: the wavelength and maximum increase in attenuation both
at T and T and after returning to thermal stability at
A B
ambient temperature shall be agreed between the
customer and the supplier
4.4 Transmission requirements
The transmission requirements shall be verified in accordance with IEC 60793-2 and shall be
agreed between the customer and the supplier. Maximum cable attenuation shall comply with
IEC 60794-1-1.
4.5 Fire performance
IEC/TR 62222 provides guidance and recommendations for the requirements and test
methods for the fire performance of communication cables when installed in buildings. The
recommendations relate to typical applications and installation practices, and an assessment
of the fire hazards presented. Applicable legislation and regulation are also taken into account.
IEC/TR 62222 references several IEC fire performance test methods and also other test
methods that may be required by local or National legislation and regulation. The tests to be
applied, and the requirements, shall be agreed between the customer and supplier taking into

– 12 – 60794-2-20  IEC:2008
account the fire hazard presented by the end use application of the patchcord assembly in
which the cable is intended to be used.

60794-2-20  IEC:2008 – 13 –
Annex A
(informative)
Examples of cable constructions

Coated fibre
Thermoplastic buffer
Strength member
Dielectric central member
Overcoat
Sheath
IEC 1992/08
Figure A.1 – Example of cross-section of a 12 fibre distribution cable

Buffered fibre
Subunit sheath
Strength member
Overcoat
Dielectric central member
Strength member
Dielectric central member
Ripcord
Sheath
IEC 1993/08
Figure A.2 – Example of cross-section of a 36 fibre distribution cable

– 14 – 60794-2-20  IEC:2008
Coated fibre
Thermoplastic buffer
Strength member
Subunit sheath
Strength member
Dielectric central member
Overcoat
Sheath
IEC 1994/08
Figure A.3 – Example of cross-section of a 6 fibre break-out cable
Dielectric central member
Single fibre subunit
6 fibre unit
Dielectric central member
Strength member
Sheath
Ripcord
IEC 1995/08
Figure A.4 – Example of cross-section of a 24 fibre break-out cable

60794-2-20  IEC:2008 – 15 –
Sheath
4 fibre ribbon
Slotted core
Strength member
Ripcord
IEC 1996/08
Figure A.5 – Example of cross-section of a slotted core type indoor cable
with 4 fibre ribbons
Sheath
2 fibre ribbon
SZ slotted rod
Strength member
Ripcord
IEC 1997/08
Figure A.6 – Example of cross-section of an SZ (reverse oscillating lay) slotted core
type indoor cable with 2 fibre ribbons

– 16 – 60794-2-20  IEC:2008
Sheath
4 fibre bundles
SZ slotted rod
Strength member
Ripcord
IEC 1998/08
Figure A.7 – Example of cross-section of an SZ (reverse oscillating lay) slotted core
type indoor cable with 4 fibre bundles
Fibres (loose or bundled)
Tube
Strength member
Sheath
IEC 1999/08
Figure A.8 – Example of multi-fibre unitube cable

60794-2-20  IEC:2008 – 17 –
Coated fibres
Thermoplastic buffer
Strength member
Sheath
IEC 2000/08
Figure A.9 – Example of multi-fibre cable

– 18 – 60794-2-20  IEC:2008
Annex B
(informative)
Family specification for multi-fibre optical distribution cables –
Blank detail specification and minimum requirements

B.1 Blank detail specification
B.1.1 Cable description
Table B.1 – Cable description
(1) Prepared by (2) Document No:
Issue:
Date:
(3) Available from (4) Generic specification: IEC 60794-1-1
Sectional specification: IEC 60794-2
(5) Additional references: ISO/IEC 24702 if required
(6) Cable description:
(7) Cable construction:
Optical fibres
Range of fibre count
Modularity
Construction Additional remarks
- single coloured fibre
- tube – filled
- tube – unfilled
- slotted core – filled
- slotted core – unfilled
- tight or semi-tight buffer
- ribbon in slotted core
- ribbon in tube
- strength elements – non metallic
- strength elements – metallic
Lay-up
- stranding (helical or reverse oscillating/SZ)
- single unit
- hybrid configuration
- other
Insulated copper conductors
- AWG
- solid/stranded
- insulation material
Inner sheath
- material
- minimum wall thickness
Peripheral strength member
- metallic
- non-metallic
60794-2-20  IEC:2008 – 19 –
Table B.1 (continued)
Outer Sheath
- material
- minimum wall thickness
Additional armouring
- non-metallic armouring
- metallic armouring
Marking identification
- customer requirement
- identification of supplier
(8) Application information:
Application
Maximum outer diameter (d) mm
Rated maximum tensile load N
Minimum bending radius for operation mm or nxd
Minimum bending radius under load mm or nxd
Temperature range:
- transport and storage ºC
- installation ºC
- operation ºC
Manufacturing cable length
- typical m
- nominal/tolerances: −0 +1%
B.1.2 Cable element
Table B.2 – Cable element
Characteristics (9) IEC 60794-2 Family Test methods Remarks (13)
Clause/subclause requirements (12)
(10) (11)
Cable element
Tight/semi-tight buffer
Slotted core
Tube
Compound flow and
evaporation
Outer diameter
Ribbon
Filler
Insulated copper conductor
Central strength member
– 20 – 60794-2-20  IEC:2008
B.1.3 Cable construction
Table B.3 – Cable construction
Characteristics (9) IEC 60794-2 Family Test methods (12) Remarks (13)
Clause/subclause requirements
(10) (11)
Lay-up 6.2 acc. DS Visual inspection
Cable core 6.3 acc. DS
Strength member 6.4 Acc. DS Visual inspection
- central
- peripheral
Outer cable sheath 6.6
Material IEC 60794-2,
6.6.3
Minimum sheath Acc. DS IEC 60811-1-1
thickness
Outer diameter Acc. DS IEC 60811-1-1
Optional protection Acc. DS
Sheath marking 6.7
Configuration, Acc. DS Visual inspection
dimensions
Abrasion resistance Acc. DS
IEC 60794-1-2,
Method E2B, Method 1
Or
IEC 60794-1-2,
Method E2B, Method 2
Sheath abrasion 8.10 Acc. DS IEC 60794-1-2,
Method E2A
Cable length
B.1.4 Installation and operating conditions
Table B.4 – Installation and operating conditions
Characteristics (9) IEC 60794-2 Family Test methods (12) Remarks (13)
Clause/subclause requirements
(10) (11)
General requirements
Bend of cable element
IEC 60794-1-2,
Method G1
Tube kinking  IEC 60794-1-2,
Method G7
Ribbons:
- dimensions  IEC 60794-2
7.2.3.1
- separability of  IEC 60794-1-2,
individual fibres Method G5
from ribbon or acc. DS
- ribbon stripping
- torsion  IEC 60794-1-2,
Method G6
60794-2-20  IEC:2008 – 21 –
B.1.5 Mechanical and environmental tests
Table B.5 – Tests applicable
Characteristics (9) IEC 60794-2 Family Test methods (12) Remarks (13)
Clause/subclause requirements
(10) (11)
Tensile performance  IEC 60794-1-2,
Method E1A and E1B
Installation capability
(selection from the
following)
- bending under  IEC 60794-1-2,
tension Method E18
- repeated bending  IEC 60794-1-2,
Method E6
- impact  IEC 60794-1-2,
Method E4
- kink  IEC 60794-1-2,
Method E10
- torsion  IEC 60794-1-2,
Method E7
Cable bend  IEC 60794-1-2,
Method E11
Crush  IEC 60794-1-2,
Method E3
Temperature cycling  IEC 60794-1-2,
Method F1
Ageing
- coating adhesion  IEC 60794-1-2,
stability Method E5
- finished cable
B.2 Additional requirements for cables subject to the MICE environmental
classification (ISO/IEC 24702 and related standards)
B.2.1 General
Cables intended for installation according to ISO/IEC 24702 and related standards may
require the specification of additional tests to ensure their suitability in the applicable
environments defined by the mechanical, ingress, climatic and chemical, and electromagnetic
(MICE) classification. For supplemental guidance, see IEC/TR 62362. Required tests may be
selected from Table B.6 below.

– 22 – 60794-2-20  IEC:2008
B.2.2 Applicable additional specifications for industrial premises installations as
defined in ISO/IEC 24702
Table B.6 – Specifications for industrial premises installations
as defined in ISO/IEC 24702
Characteristics MICE classification of ISO/IEC 24702 Test method
a, b
and related standards
MECHANICAL M M M
1 2 3
a
Shock/bump
–2 –2 –2
Peak acceleration 40 ms 100 ms 250 ms IEC 60721-3-3
a
Vibration
Displacement amplitude 1,5 mm 7,0 mm 15,0 mm IEC 60721-1
(2 Hz to 9 Hz)
–2 –2 –2
Acceleration amplitude 5 ms 20 ms 50 ms IEC 60721-1
(9 Hz to 500 Hz)
Tensile force (see NOTE 1) As required As required As required IEC 60794-1-2,
Method E1
Crush 180 N/ 733 N/ 1 467 N/
100 mm 100 mm 100 mm
Crush Requirement above Requirement above Requirement above IEC 60794-1-2,
converted to converted to converted to
Method E3
requirement for IEC requirement for IEC requirement for IEC
plate/plate test plate/plate test plate/plate test
Impact 1 J 10 J 30 J IEC 60794-1-2,
Striking surface Striking surface Striking surface
Method E4
radius : radius : radius :
10 mm or 300 mm 10 mm or 300 mm 10 mm or 300 mm
Bending (see NOTE 1) As required As required As required IEC 60794-1-2,
Method E6
Flexing (see NOTE 1) As required As required As required IEC 60794-1-2,
Method E8
Torsion (see NOTE 1) As required As required As required IEC 60794-1-2,
Method E7
INGRESS I I I
1 2 3
b
Immersion N/A Intermittent liquid jet Intermittent liquid jet IEC 60794-1-2,
Method F3
≤ 12,5 l/min ≤ 12,5 l/min
≥ 6,3 mm/jet ≥ 6,3 mm/jet
> 2,5 m distance > 2,5 m distance
and
immersion
≤ 1m for ≤ 30 min
CLIMATIC and CHEMICAL C C C
1 2 3
Temperature cycling −10 °C to +60 °C −25 °C to +70 °C −40 °C to +70 °C IEC 60794-1-2,
(ambient and rate of Method F1
change)
b –2 –2 –2
Solar radiation 700 Wm 1 120 Wm 1 120 Wm IEC 60721-1
b
Humidity 5 % to 85 % (non- 5 % to 95 % 5 % to 95 % IEC 60721-3-3
condensing) (condensing) (condensing)
–6 –6 –6
Liquid pollution
Concentration × 10 Concentration × 10 Concentration × 10
contaminants
60794-2-20  IEC:2008 – 23 –
Characteristics MICE classification of ISO/IEC 24702 Test method
a, b
and related standards
(see NOTE 2)
Sodium chloride (salt/sea 0 IEC 60721-1
< 0,3 < 0,3
b
water)
b
Oil (dry-air concentration) 0
< 0,005 < 0,5
(for oil types see NOTE 1)
a
4 4
Sodium stearate (soap) None ISO/IEC 24702
> 5 × 10 aqueous > 5 × 10 aqueous
non-gelling gelling
Gaseous pollution Mean/peak Mean/peak Mean/peak
–6 –6 –6
contaminants concentration × 10 concentration × 10 concentration × 10
(see Note2)
a
Hydrogen sulphide < 0,003/< 0,01 < 0,05/< 0,5 < 10/< 50 IEC 60654-4
a
Sulphur dioxide IEC 60654-4
< 0,01/< 0,03 < 0,1/< 0,3 < 5/< 15
a
Sulphur trioxide (ffs) IEC 60654-4
< 0,01/< 0,03 < 0,1/<0,3 < 5/< 15
Chlorine wet (> 50 % < 0,0005 < 0,005/< 0,03 < 0,05/< 0,3 IEC 60654-4
b
humidity)
/< 0,001
Chlorine dry (< 50 % < 0,002/<0,01 < 0,02/< 0,1 < 0,2/< 1,0 IEC 60654-4
b
humidity)
b
Hydrogen chloride IEC 60654-4
0/< 0,06 < 0,06/< 0,3 < 0,6/< 3,0
b
Hydrogen fluoride IEC 60654-4
< 0,001/< 0,005 < 0,01/< 0,05 < 0,1/< 1,0
b
Ammonia < 1,0/<5,0 < 10,0/< 50,0 < 50/< 250 IEC 60654-4
b
Oxides of nitrogen IEC 60654-4
< 0,05/< 0,1 < 0,5/< 1,0 < 5/< 10
b
Ozone IEC 60654-4
< 0,002/< 0,005 < 0,025/< 0,05 < 0,1/< 1
ELECTRO-MAGNETIC E E
E
1 2 3
(for cables containing
electrically conductive
elements)
Electrostatic discharge – 4 kV 4 kV 4 kV IEC 61326-1
a
Contact (0,667 µC)
Electrostatic discharge – 8 kV 8 kV 8 kV IEC 61326-1
a
Air (0,132 µC)
a
Radiated RF – AM 3 V/m @ (80 to 3 V/m @ (80 to 10 V/m @ (80 to IEC 61000-2-5
1 000) MHz 1 000) MHz 1 000) MHz
3 V/m @ (1 400 to 3 V/m @ (1 400 to 3 V/m @ (1 400 to
2 000) MHz 2 000) MHz 2 000) MHz
1 V/m @ (2 000 to 1 V/m @ (2 000 to 1 V/m @ (2 000 to
2 700) MHz 2 700) MHz 2 700) MHz
a
Conducted RF 3 V@ 150 kHz to 3 V@ 150 kHz to 10 V@ 150 kHz to IEC 61000-6-2
80 MHz 80 MHz 80 MHz
b
EFT/B (comms) 500 V 1 000 V 1 000 V IEC 61326-1
Surge (transient ground 500 V 1 000 V 1 000 V IEC 61000-6-2
potential difference) –
b
signal, line to earth
–1 –1 –1
Magnetic field 1 Am 3 Am 30 Am IEC 61326-1
b
(50/60 Hz)
NOTE 1 This aspect of environmental classification is installation-specific and should be considered in association with
IEC 61918 and the appropriate component specification.
NOTE 2 A single dimensional characteristic, i.e. Concentration x 10-6, was chosen to unify limits from different standards.
a
Subclause 6.2.2 of ISO/IEC 24702 provides the basis for requirements.
b
Annex F of ISO/IEC 24702 explains the background to classification boundaries.

– 24 – 60
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