IEC 61156-2:2010

Multicore and symmetrical pair/quad cables for digital communications - Part 2: Symmetrical pair/quad cables with transmission characteristics up to 100 MHz - Horizontal floor wiring - Sectional specification

IEC 61156-2:2010(E) defines individually screened or unscreened pair/quad cables, with or without overall common screen for horizontal floor wiring. These cables are suitable for the various communication systems for which the reference is given in the relevant detail specification. The cables covered by this sectional specification are intended to operate with voltages and currents normally adopted for communication systems. These cables should not be connected to low impedance sources, for example, the public mains electricity supply. This third edition cancels and replaces the second edition published in 2003 and constitutes a technical revision. This new edition includes category 3 and 5 cables.
This publication is to be read in conjunction with IEC 61156-1:2002.

General Information

• Status: Published
• Publication Date: 26-Apr-2010
• ICS: 33.120.20 - Wires and symmetrical cables
• Technical Committee: SC 46C - Wires and symmetric cables
• Drafting Committee: WG 7 - TC 46/SC 46C/WG 7
• Current Stage: PPUB - Publication issued
• Start Date: 27-Apr-2010
• Completion Date: 15-May-2010

Relations

• Revises: IEC 61156-2:2003 - Multicore and symmetrical pair/quad cables for digital communications - Part 2: Horizontal floor wiring - Sectional specification
• Effective Date: 05-Sep-2023

Overview

IEC 61156-2:2010 is the sectional specification for multicore symmetrical pair/quad cables intended for horizontal floor wiring in buildings. It covers individually screened or unscreened pair/quad constructions, with or without an overall screen, and defines transmission characteristics up to 100 MHz. This third edition (2010) supersedes the 2003 edition and explicitly includes Category 3 and Category 5 cable types. IEC 61156-2 is to be read together with IEC 61156-1:2002 (generic specification).

Key topics and technical requirements

• Cable types & construction
  • Individually screened or unscreened pair/quad cables; optional overall common screen.
  • Conductors: annealed copper, normally solid, nominal diameter 0.50–0.65 mm (up to 0.80 mm if compatible with connectors).
  • Insulation: suitable thermoplastic materials; color coding per IEC colour standards.
• Electrical characteristics
  • Conductor resistance and resistance unbalance.
  • Dielectric strength and insulation resistance.
  • Mutual capacitance, capacitance unbalance, and transfer impedance for screened elements.
• Transmission parameters (to 100 MHz)
  • Velocity of propagation (phase velocity), attenuation, NEXT (near-end crosstalk), FEXT (far-end crosstalk), characteristic impedance and structural return loss (SRL).
• Mechanical & dimensional tests
  • Dimensional tolerances, elongation and tensile strength of conductors/insulation/sheath, bending, crush and impact tests.
• Environmental & safety tests
  • Thermal ageing, low-temperature bending, flame propagation (single and bunched), smoke generation, acid/halogen gas evolution and combined air-handling space tests.
• Operational limits
  • Intended for communications voltages/currents only - not to be connected to low-impedance mains supplies.
  • Normal operating temperature range: –40 °C to +60 °C; installation recommended between –10 °C and +60 °C.

Applications

IEC 61156-2 is used for specifying and testing balanced pair/quad cables for:

• Horizontal building cabling in LANs and voice/data systems (structured cabling).
• Premises wiring where transmission performance up to 100 MHz is required.
• Environments requiring specific flame, smoke or halogen performance for safety and regulatory compliance.

Who uses this standard

• Cable manufacturers designing and certifying pair/quad products.
• Test laboratories performing electrical, mechanical and fire/smoke tests.
• System integrators, network designers and building specifiers writing procurement and installation requirements.
• Authorities and compliance teams ensuring cabling meets building and safety codes.

Related standards

• IEC 61156-1:2002 (Generic specification)
• IEC 61156-2-1 (Blank detail specification)
• IEC 60304 (Insulation colour codes)
• ISO/IEC 11801 (structured cabling definitions for horizontal wiring)

Keywords: IEC 61156-2, horizontal floor wiring, symmetrical pair cables, Category 3, Category 5, 100 MHz, structured cabling, cable specification, balanced pair/quad.

Standards Content (Sample)

IEC 61156-2 ®
Edition 3.0 2010-04
INTERNATIONAL
STANDARD
Multicore and symmetrical pair/quad cables for digital communications –
Part 2: Symmetrical pair/quad cables with transmission characteristics up to
100 MHz – Horizontal floor wiring – Sectional specification

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IEC 61156-2 ®
Edition 3.0 2010-04
INTERNATIONAL
STANDARD
Multicore and symmetrical pair/quad cables for digital communications –
Part 2: Symmetrical pair/quad cables with transmission characteristics up to
100 MHz – Horizontal floor wiring – Sectional specification

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
P
ICS 33.120.20 ISBN 978-2-88910-419-2
– 2 – 61156-2 © IEC:2010(E)
CONTENTS
FOREWORD.4
1 General .6
1.1 Scope and object.6
1.2 Normative references .6
1.3 Installation considerations.6
2 Definitions and requirements.7
2.1 Definitions .7
2.2 Materials and cable construction.7
2.2.1 General remarks.7
2.2.2 Cable construction .7
2.2.3 Conductor.7
2.2.4 Insulation.7
2.2.5 Colour code of insulation.7
2.2.6 Cable element .7
2.2.7 Screening of the cable element .8
2.2.8 Cable make-up .8
2.2.9 Screening of the cable core.8
2.2.10 Sheath.8
2.2.11 Colour of sheath .8
2.2.12 Identification .8
2.2.13 Finished cable .8
3 Characteristics and requirements.9
3.1 General remarks.9
3.2 Electrical characteristics .9
3.2.1 Conductor resistance .9
3.2.2 Resistance unbalance.9
3.2.3 Dielectric strength.9
3.2.4 Insulation resistance .9
3.2.5 Mutual capacitance .9
3.2.6 Capacitance unbalance.9
3.2.7 Transfer impedance.10
3.3 Transmission characteristics.10
3.3.1 Velocity of propagation (phase velocity) .10
3.3.2 Attenuation .11
3.3.3 Unbalance attenuation .11
3.3.4 Near-end crosstalk (NEXT) .11
3.3.5 Far-end crosstalk.11
3.3.6 Characteristic impedance.12
3.3.7 Structural return loss (SRL) .12
3.4 Mechanical and dimensional characteristics and requirements .13
3.4.1 Dimensional requirements.13
3.4.2 Elongation at break of the conductors .13
3.4.3 Elongation at break of the insulation.13
3.4.4 Elongation at break of the sheath.13
3.4.5 Tensile strength of the sheath .13
3.4.6 Crush test of the cable.13
3.4.7 Impact test of the cable.13

61156-2 © IEC:2010(E) – 3 –
3.4.8 Bending under tension .13
3.4.9 Tensile performance of the cable .13
3.5 Environmental characteristics .13
3.5.1 Shrinkage of insulation.13
3.5.2 Wrapping test of insulation after thermal ageing .13
3.5.3 Bending test of insulation at low temperature .14
3.5.4 Elongation at break of the sheath after ageing.14
3.5.5 Tensile strength of the sheath after ageing.14
3.5.6 Sheath pressure test at high temperature.14
3.5.7 Cold bend test of the cable .14
3.5.8 Heat shock test.14
3.5.9 Flame propagation characteristics of a single cable.14
3.5.10 Flame propagation characteristics of bunched cables.14
3.5.11 Acid gas evolution.14
3.5.12 Smoke generation.14
3.5.13 Toxic gas emission .14
3.5.14 Combined flame and smoke test for cables in environmental air
handling space .15
4 Introduction to the blank detail specification .15
Bibliography .16

Table 1 – Constants .11
Table 2 – NEXT constants.11
Table 3 – Input impedance values .12
Table 4 – Function fitted impedance .12
Table 5 – Structural return loss (dB min) .12

– 4 – 61156-2 © IEC:2010(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MULTICORE AND SYMMETRICAL PAIR/QUAD CABLES
FOR DIGITAL COMMUNICATIONS –
Part 2: Symmetrical pair/quad
cables with transmission characteristics up to 100 MHz –
Horizontal floor wiring – Sectional specification

FOREWORD
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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 61156-2 has been prepared by subcommittee 46C: Wires and
symmetric cables, of IEC technical committee 46: Cables, wires, waveguides, r.f. connectors,
r.f. and microwave passive components and accessories.
This third edition cancels and replaces the second edition published in 2003 and constitutes a
technical revision. This new edition includes category 3 and 5 cables.
This standard is to be read in conjunction with IEC 61156-1:2002.

61156-2 © IEC:2010(E) – 5 –
The text of this standard is based on the following documents:
FDIS Report on voting
46C/911/FDIS 46C/914/RVD
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 the parts in the IEC 61156 series, under the general title Multicore and symmetrical
pair/quad cables for digital communications, 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.
A bilingual version of this publication may be issued at a later date.

– 6 – 61156-2 © IEC:2010(E)
MULTICORE AND SYMMETRICAL PAIR/QUAD CABLES
FOR DIGITAL COMMUNICATIONS –
Part 2: Symmetrical pair/quad
cables with transmission characteristics up to 100 MHz –
Horizontal floor wiring – Sectional specification

1 General
1.1 Scope and object
This sectional specification relates to IEC 61156-1:2002. The cables are specifically intended
for horizontal floor wiring as defined in ISO/IEC 11801:1995.
This specification defines individually screened or unscreened pair/quad cab
...