IEC 61935-1-2:2018

IEC 61935-1-2 ®
Edition 1.0 2018-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Specification for the testing of balanced and coaxial information technology
cabling –
Part 1-2: Installed balanced cabling as specified in ISO/IEC 11801 – Additional
requirements for measurement of resistance unbalance with field test
instrumentation
Spécification relative aux essais des câblages symétriques et coaxiaux des
technologies de l’information –
Partie 1-2: Câblages symétriques installés tels que spécifiés dans
l’ISO/IEC 11801 – Exigences supplémentaires pour le mesurage de l’asymétrie

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite ni
utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et
les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.

IEC Central Office Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and electrical
bibliographical information on IEC International Standards, terms containing 21 000 terms and definitions in English and
Technical Specifications, Technical Reports and other French, with equivalent terms in 16 additional languages. Also
documents. Available for PC, Mac OS, Android Tablets and known as the International Electrotechnical Vocabulary (IEV)
iPad. online.
IEC publications search - webstore.iec.ch/advsearchform IEC Glossary - std.iec.ch/glossary
The advanced search enables to find IEC publications by a 67 000 electrotechnical terminology entries in English and
variety of criteria (reference number, text, technical French extracted from the Terms and Definitions clause of IEC
committee,…). It also gives information on projects, replaced publications issued since 2002. Some entries have been
and withdrawn publications. collected from earlier publications of IEC TC 37, 77, 86 and

CISPR.
IEC Just Published - webstore.iec.ch/justpublished

Stay up to date on all new IEC publications. Just Published IEC Customer Service Centre - webstore.iec.ch/csc
details all new publications released. Available online and also If you wish to give us your feedback on this publication or need
once a month by email. further assistance, please contact the Customer Service
Centre: sales@iec.ch.
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.

Catalogue IEC - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
Application autonome pour consulter tous les renseignements
Le premier dictionnaire en ligne de termes électroniques et
bibliographiques sur les Normes internationales, Spécifications
électriques. Il contient 21 000 termes et définitions en anglais
techniques, Rapports techniques et autres documents de l'IEC.
et en français, ainsi que les termes équivalents dans 16
Disponible pour PC, Mac OS, tablettes Android et iPad.
langues additionnelles. Egalement appelé Vocabulaire

Electrotechnique International (IEV) en ligne.
Recherche de publications IEC -

webstore.iec.ch/advsearchform
Glossaire IEC - std.iec.ch/glossary
La recherche avancée permet de trouver des publications IEC 67 000 entrées terminologiques électrotechniques, en anglais
en utilisant différents critères (numéro de référence, texte, et en français, extraites des articles Termes et Définitions des
comité d’études,…). Elle donne aussi des informations sur les publications IEC parues depuis 2002. Plus certaines entrées
projets et les publications remplacées ou retirées. antérieures extraites des publications des CE 37, 77, 86 et

CISPR de l'IEC.
IEC Just Published - webstore.iec.ch/justpublished

Service Clients - webstore.iec.ch/csc
Restez informé sur les nouvelles publications IEC. Just
Published détaille les nouvelles publications parues. Si vous désirez nous donner des commentaires sur cette
Disponible en ligne et aussi une fois par mois par email. publication ou si vous avez des questions contactez-nous:
sales@iec.ch.
IEC 61935-1-2 ®
Edition 1.0 2018-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Specification for the testing of balanced and coaxial information technology

cabling –
Part 1-2: Installed balanced cabling as specified in ISO/IEC 11801 – Additional

requirements for measurement of resistance unbalance with field test

instrumentation
Spécification relative aux essais des câblages symétriques et coaxiaux des

technologies de l’information –

Partie 1-2: Câblages symétriques installés tels que spécifiés dans

l’ISO/IEC 11801 – Exigences supplémentaires pour le mesurage de l’asymétrie

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.120.10 ISBN 978-2-8322-6168-2

– 2 – IEC 61935-1-2:2018 © IEC 2018
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Reference measurement procedure for resistance unbalance . 5
4.1 Reference measurement procedure for resistance unbalance within a pair. 5
4.2 Reference measurement procedure for resistance unbalance between pairs . 6
4.3 Measurement setup for field measurement of resistance unbalance
parameters . 6
5 Field tester requirements for resistance unbalance measurements . 6
5.1 General . 6
5.2 Data reporting and accuracy . 7
5.2.1 Detailed results . 7
5.2.2 Summary results . 7
6 Field tester accuracy performance requirements for resistance unbalance
measurements . 8
7 Accuracy models . 8
7.1 Error model for DC loop resistance . 8
7.2 Error model for resistance unbalance . 9
7.3 Comparison to reference measurements . 9
7.4 Procedures for determining field tester parameters . 9
7.4.1 General . 9
7.4.2 Constant error term of DC loop resistance for loop resistance
measurements . 9
7.4.3 Error term proportional to the DC loop resistance for loop resistance
measurements . 9
7.4.4 Constant error term of resistance unbalance for resistance unbalance
measurements . 9
7.4.5 Error term proportional to the DC loop resistance for resistance
unbalance measurements . 10

Figure 1 – Measurement setup . 6

Table 1 – Additional field test requirements for resistance unbalance measurements . 7
Table 2 – Field tester summary reporting requirements for resistance unbalance
measurements . 8
Table 3 – Accuracy requirements for resistance unbalance measurements . 8

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SPECIFICATION FOR THE TESTING OF BALANCED AND COAXIAL
INFORMATION TECHNOLOGY CABLING –

Part 1-2: Installed balanced cabling as specified in ISO/IEC 11801 –
Additional requirements for measurement of resistance unbalance
with field test instrumentation

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-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
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 61935-1-2 has been prepared by IEC technical committee TC 46:
Cable
...