IEC 61935-1-2:2018

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

IEC 61935-1-2:2018 specifies additional reference measurement procedures for measurement of resistance unbalance with field test instrumentation, and the requirements for field tester accuracy to measure resistance unbalance according to the requirements of ISO/IEC 11801-1.

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

l’IEC 61935-1-2:2018 spécifie les procédures de mesure de référence supplémentaires pour le mesurage de l’asymétrie de résistance avec des instruments d’essai sur site et les exigences relatives à l’exactitude des contrôleurs sur site pour mesurer l’asymétrie de résistance conformément aux exigences de l'ISO/IEC 11801-1.

General Information

• Status: Published
• Publication Date: 13-Dec-2018
• ICS: 33.120.10 - Coaxial cables. Waveguides
• Technical Committee: TC 46 - Cables, wires, waveguides, RF connectors, RF and microwave passive components and accessories
• Drafting Committee: WG 9 - TC 46/WG 9
• Current Stage: PPUB - Publication issued
• Start Date: 14-Dec-2018
• Completion Date: 19-Oct-2018

Standards Content (Sample)

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

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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
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International Standard IEC 61935-1-2 has been prepared by IEC technical committee TC 46:
Cables, wires, waveguides, RF connectors, RF and microwave passive components and
accessories.
The text of this International Standard is based on the following documents:
FDIS Report on voting
46/695/FDIS 46/702/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.

– 4 – IEC 61935-1-2:2018 © IEC 2018
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 61935 series, published under the general title Specification for
the testing of balanced and coaxial information technology cabling, can be found on the IEC
website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document 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.
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

1 Scope
This part of IEC 61935 specifies additional reference measurement procedures for
measurement of resistance unbalance with field test instrumentation, and the requirements for
field tester accuracy to measure resistance unbalance according to the requirements of
ISO/IEC 11801-1.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements 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.
IEC 61935-1, Specification for the testing of balanced and coaxial information technology
cabling – Part 1: Installed balanced cabling as specified in ISO/IEC 11801 and related
standards
ISO/IEC 11801-1, Information technology – Generic cabling for customer premises –
Part 1:General requirements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61935-1 and
ISO/IEC 11801-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 Reference measurement procedure for resistance unbalance
4.1 Reference measurement procedure for resistance unbalance within a pair
DC resistance unbalance within a pair shall be calculated for each pair using individual
resistance measurements of each conductor within the pair according to Equation (1);
|𝑅𝑅 −𝑅𝑅 |
1 2
𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅_𝑈𝑈𝑅𝑅𝑈𝑈𝑅𝑅𝑈𝑈𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅 =� � 100 %
within_a_pair
(1)
𝑅𝑅 +𝑅𝑅
1 2
– 6 – IEC 61935-1-2:2018 © IEC 2018
where
R is the resistance of conductor 1;
R is the resistance of conductor 2.
4.2 Reference measurement procedure for resistance unbalance between pairs
DC resistance unbalance between pairs shall be calculated for all pair combinations using
measurements of the parallel resistance of each pair according to Equation (2);
|𝑅𝑅 −𝑅𝑅 |
3 4
𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅_𝑈𝑈𝑅𝑅𝑈𝑈𝑅𝑅𝑈𝑈𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅 =� � 100 %
between_pairs
(2)
𝑅𝑅 +𝑅𝑅
3 4
where
R is the parallel resistance of pair 1;
R is the parallel resistance of pair 2.
4.3 Measurement setup for field measurement of resistance unbalance parameters
The field tester measurement setup for resistance unbalance and resistance unbalance
between pairs is provided by Figure 1.
DUT
Near end Far end
field tester field tester
Screen (if present)
IEC
Figure 1 – Measurement setup
5 Field tester requirements for resistance unbalance measurements
5.1 General
The field tester shall comply with the requirements of the applicable level requirements of
IEC 61935-1 and the requirements of Table 1. For the purposes of field measurements,
calculations of limits that provide values of less than 200 mΩ shall revert to 200 mΩ.

Table 1 – Additional field test requirements for resistance
unbalance measurements
Field tester
Baseline field Field tester with permanent
Parameter with channel
tester link adapter
adapter
DC loop resistance
0,01 Ω
resolution
Constant error term of
DC loop resistance
0,5 Ω
E
c,DC_r
Error term proportional to
the DC loop resistance
1 %
E
d,DC_r
DC resistance unbalance
0,005 %
resolution
Constant error term of
DC resistance unbalance
0,025 Ω
E
c,DC_unbalance
0,3
Error term proportional to
the DC resistance for DC loop resistance for resistance unbalance within a pair
%
resistance unbalance
or
E
d,DC_unbalance
Mean of DC loop resistances for resistance unbalance between pairs
NOTE The requirements for measurements of resistance unbalance are not based on the requirements for loop
resistance measurements.
5.2 Data reporting and accuracy
5.2.1 Detailed results
The field test equipment shall be capable of recording all connectivity information, as well as
the measured values of resistance unbalance between pairs and within a pair. In addition, the
detailed results shall include a PASS/FAIL result for resistance unbalance between pairs and
within a pair.
5.2.2 Summary results
Detailed information may be required in certain circumstances; however, in general, summary
performance information is sufficient. The field test equipment shall be capable of reporting
the minimum summary information as shown in Table 2.

– 8 – IEC 61935-1-2:2018 © IEC 2018
Table 2 – Field tester summary reporting requirements for
resistance unbalance measurements
Measured from
Measured from local or
remote end (if
remote end
Test parameter measurement from
(if measurement from both
remote end is
directions is not required)
required)
Worst case resistance
unbalance between pairs
margin
(1 of 6 possible).
Test limit at worst case
Resistance unbalance
resistance unbalance
(between pairs)
between pairs margin.
Resistance unbalance
between pairs at worst case
margin.
PASS/FAIL.
Worst case resistance
unbalance within a pair
margin
(1 of 4 possible).
Resistance unbalance
Test limit at worst case
resistance unbalance within
(within a pair)
a pair margin.
Resistance unbalance within
a pair at worst case margin.
PASS/FAIL.
6 Field tester accuracy performance requirements for resistance unbalance
measurements
The accuracy of field tester measurements of resistance unbalance between pairs shall be
given by Table 3.
Table 3 – Accuracy requirements for resistance unbalance measurements
Baseline accuracy at
Permanent link accuracy Channel accuracy at
Test parameter permanent link
at permanent link limits channel limits
limits
DC loop resistance ± (0,5 Ω + 1 % DC loop resistance)
DC resistance unbalance
± (0,025 Ω + 0,3 % mean DC loop resistance)
between pairs
DC resistance unbalance
± (0,025 Ω + 0,3 % DC loop resistance)
within a pair
NOTE The accuracy for measurements of resistance unbalance is not based on the requirements for loop
resistance measurements.
7 Accuracy models
7.1 Error model for DC loop resistance
The error model for DC loop resistance is provided by the addition of the constant error term
) and the error term proportional to DC loop resistance (𝐸𝐸 ).
of DC loop resistance (𝐸𝐸
c,DC_r D,DC_r
7.2 Error model for resistance unbalance
The error model for resistance unbalance, within a pair and between pairs, is provided by the
addition of the constant error term of resistance unbalance (𝐸𝐸 ) and the error term of
c,DC_unbalance
resistance unbalance proportional to DC resistance (𝐸𝐸 ).
D,DC_unbalance
7.3 Comparison to reference measurements
Comparison of results to the reference measurements of IEC 61935-1 shall be according to
the single value test results method of IEC 61935-1.
7.4 Procedures for determining field tester parameters
7.4.1 General
Field test equipment is designed with two units that are attached to opposite ends of the
cabling to be tested. Internal to these units are source and load ports that are used for
measurements. The following measurements shall be used to determine compliance with the
specified requirements.
7.4.2 Constant error term of DC loop resistance for loop resistance measurements
The procedure for determining the constant error term of DC loop resistance, 𝐸𝐸 , is
c,DC_r
provided by connecting a connector to the field tester with shorts across each pair. The
reported DC resistance in each case shall be less than the 𝐸𝐸 .
c,DC_r
7.4.3 Error term proportional to the DC loop resistance for loop resistance
measurements
The DC resistance of cabling with a total length of approximately 30 m shall be measured
using a four-terminal ohmmeter and with a specified accuracy of at least 0,01 %. The DC
resistance of the same cabling, measured with the field tester, less the observed resistance
value with the pair shorted (constant error term of DC loop resistance) shall be less than the
error constant term proportional to the DC resistance.
Ω −𝐸𝐸
Fieldtester c,DC_r
𝐸𝐸 =
d,DC_r
(3)
Ω
FourWire
where
𝐸𝐸 is the error term proportional to DC loop resistance;
d,DC_r
Ω is the the value of the DC loop resistance as measured on the field tester;
Fieldtester
Ω is the the value of the DC loop resistance as measured on the four wire ohmmeter.
FourWire
7.4.4 Constant error term of resistance unbalance for resistance unbalance
measurements
The procedure for determining the constant error
...