Electrical safety in low voltage distribution systems up to 1 000 V AC and 1 500 V DC - Equipment for testing, measuring or monitoring of protective measures - Part 4: Resistance of earth connection and equipotential bonding

IEC 61557-4:2019 is available as IEC 61557-4:2019 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 61557-4:2019 specifies the requirements applicable to equipment for measuring the resistance of earth conductors, protective earth conductors and conductors for equipotential bonding, including their connections and terminals, with an indication of the measured value or an indication of the limits. IEC 61557-4:2019 cancels and replaces the second edition published in 2007. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) complement to the measurement category in Clause 4;
b) correction of the equation for operating uncertainty;
c) complement to the requirements for measuring with DC;
d) alignment of the structure with that of the whole IEC 61557 series.

Sécurité électrique dans les réseaux de distribution basse tension au plus égale à 1 000 V c.a. et 1 500 V c.c. - Dispositifs de contrôle, de mesure ou de surveillance de mesures de protection - Partie 4: Résistance de conducteurs de terre et d'equipotentialité

IEC 61557-4:2019 est disponible sous forme de IEC 61557-4:2019 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.L'IEC 61557-4:2019 spécifie les exigences applicables aux appareils destinés à mesurer la résistance de conducteurs de terre, de conducteurs de terre de protection et de conducteurs d'équipotentialité, y compris leurs liaisons et bornes, avec une indication de la valeur mesurée ou une indication des limites. L'IEC 61557-4:2019 annule et remplace la deuxième édition parue en 2007. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) développement des informations concernant la catégorie de mesure à l'Article 4;
b) correction de l'équation relative à l'incertitude de fonctionnement;
c) développement des exigences de mesure de la tension continue;
d) alignement de la structure sur l'ensemble de la série IEC 61557.

General Information

Status
Published
Publication Date
25-Jul-2019
Current Stage
PPUB - Publication issued
Start Date
09-Aug-2019
Completion Date
26-Jul-2019
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IEC 61557-4:2019 - Electrical safety in low voltage distribution systems up to 1 000 V AC and 1 500 V DC - Equipment for testing, measuring or monitoring of protective measures - Part 4: Resistance of earth connection and equipotential bonding
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IEC 61557-4
®

Edition 3.0 2019-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Electrical safety in low voltage distribution systems up to 1 000 V a.c. and
1 500 V d.c. – Equipment for testing, measuring or monitoring of protective
measures –
Part 4: Resistance of earth connection and equipotential bonding

Sécurité électrique dans les réseaux de distribution basse tension au plus égale
à 1 000 V c.a. et 1 500 V c.c. – Dispositifs de contrôle, de mesure ou de
surveillance de mesures de protection –
Partie 4: Résistance de conducteurs de terre et d'équipotentialité

IEC 61557-4:2019-07(en-fr)

---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 61557-4

®


Edition 3.0 2019-07




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE











Electrical safety in low voltage distribution systems up to 1 000 V a.c. and

1 500 V d.c. – Equipment for testing, measuring or monitoring of protective

measures –


Part 4: Resistance of earth connection and equipotential bonding



Sécurité électrique dans les réseaux de distribution basse tension au plus égale


à 1 000 V c.a. et 1 500 V c.c. – Dispositifs de contrôle, de mesure ou de

surveillance de mesures de protection –

Partie 4: Résistance de conducteurs de terre et d'équipotentialité










INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 17.220.20; 29.080.01; 29.240.01 ISBN 978-2-8322-7158-2




Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

---------------------- Page: 3 ----------------------
– 2 – IEC 61557-4:2019 © IEC 2019
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Requirements . 5
4.1 General . 5
4.2 Measuring voltage. 6
4.3 Measuring current . 6
4.4 Measuring with DC . 6
4.5 Measuring range . 6
4.6 External resistance . 6
4.7 Indication of limits . 6
4.8 Overvoltage . 7
5 Marking and operating instructions . 7
5.1 Marking . 7
5.2 Operating instructions . 7
6 Tests . 7
6.1 General . 7
6.2 Operating uncertainty . 7
6.3 Open-circuit voltage . 8
6.4 Measuring current . 8
6.5 Indication of limits . 8
6.6 Overvoltage . 8
6.7 Battery life in battery operated instruments . 9
Bibliography . 10

Table 1 – Calculation of operating uncertainty . 8

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IEC 61557-4:2019 © IEC 2019 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

ELECTRICAL SAFETY IN LOW VOLTAGE DISTRIBUTION SYSTEMS
UP TO 1 000 V AC AND 1 500 V DC –
EQUIPMENT FOR TESTING, MEASURING OR MONITORING
OF PROTECTIVE MEASURES –

Part 4: Resistance of earth connection
and equipotential bonding

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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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 61557-4 has been prepared by IEC technical committee 85:
Measuring equipment for electrical and electromagnetic quantities.
This third edition cancels and replaces the second edition published in 2007. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) complement to the measurement category in Clause 4;
b) correction of the equation for operating uncertainty;
c) complement to the requirements for measuring with DC;

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– 4 – IEC 61557-4:2019 © IEC 2019
d) alignment of the structure with that of the whole IEC 61557 series.
The text of this International Standard is based on the following documents:
FDIS Report on voting
85/686/FDIS 85/695/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.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
This International Standard is to be used in conjunction with IEC 61557-1:2019.
A list of all parts of the IEC 61557 series, published under the general title Electrical safety in
low voltage distribution systems up to 1 000 V AC and 1 500 V DC – Equipment for testing,
measuring or monitoring of protective measures, 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.

---------------------- Page: 6 ----------------------
IEC 61557-4:2019 © IEC 2019 – 5 –
ELECTRICAL SAFETY IN LOW VOLTAGE DISTRIBUTION SYSTEMS
UP TO 1 000 V AC AND 1 500 V DC –
EQUIPMENT FOR TESTING, MEASURING OR MONITORING
OF PROTECTIVE MEASURES –

Part 4: Resistance of earth connection
and equipotential bonding



1 Scope
This part of IEC 61557 specifies the requirements applicable to equipment for measuring the
resistance of earth conductors, protective earth conductors and conductors for equipotential
bonding, including their connections and terminals, with an indication of the measured value
or an indication of the limits.
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 61010-031, Safety requirements for electrical equipment for measurement, control and
laboratory use – Part 031: Safety requirements for hand-held and hand-manipulated probe
assemblies for electrical test and measurement
IEC 61010-2-030:2017, Safety requirements for electrical equipment for measurement, control,
and laboratory use – Part 2-030: Particular requirements for equipment having testing or
measuring circuits
IEC 61557-1:2019, Electrical safety in low voltage distribution systems up to 1 000 V AC and
1 500 V DC – Equipment for testing, measuring or monitoring of protective measures – Part 1:
General requirements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61557-1 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 Requirements
4.1 General
In addition to the requirements of IEC 61557-1:2019, Clause 4, the following requirements
shall apply.

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– 6 – IEC 61557-4:2019 © IEC 2019
Equipment intended for making measurements on distribution systems shall, at the minimum,
be rated for measurement category III in accordance with IEC 61010-2-030.
Equipment intended for making measurements on electrical equipment shall, at the minimum,
be rated for measurement category II in accordance with IEC 61010-2-030.
Test leads and test probes used with the measuring equipment shall fulfil the requirements of
IEC 61010-031.
4.2 Measuring voltage
The measuring voltage may be a DC or an AC voltage. The open-circuit voltage shall not
exceed 24 V and shall not be less than 4 V.
4.3 Measuring current
The measuring current within the minimum measuring range according to 4.5 shall not be less
than 0,2 A.
4.4 Measuring with DC
Resistance measuring equipment using a DC voltage as a measuring voltage shall be
provided either with a reversing switch or allow the interchanging of test leads.
4.5 Measuring range
The measuring range within which the operating uncertainty in accordance with 6.2 is
maintained, shall include the values between 0,2 Ω and 2 Ω.
The measuring range shall be marked on the equipment. With analogue only presentation of
the measuring results, the range shall be marked on the scale.
The measuring range to be marked in accordance with 4.5 on analogue measuring equipment
shall cover at least 50 % of the length of the scale.
The division on the scale within this range shall be at least 0,5 mm per 0,1 Ω.
The resolution for digital equipment shall be at least 0,1 Ω.
The operating uncertainty applies under the rated operating conditions given in
IEC 61557-1:2019, 4.3.
4.6 External resistance
When external resistances are included in the calibration as a zero offset, then this shall be
indicated.
This offset shall remain included in the calibration as long as it is indicated on the measuring
instrument, regardless of any changes in range or function.
4.7 Indication of limits
Equipment that purely indicates the result of a comparison between measurements and limit
values shall unambiguously display if either the upper or lower limit is reached.

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IEC 61557-4:2019 © IEC 2019 – 7 –
4.8 Overvoltage
The user shall not be exposed to danger and the equipment shall not be damaged when the
measuring equipment is accidentally connected with 120 % of the nominal voltage of the
distribution system on which the measuring equipment may be used.
Protective devices of the test equipment may be activated.
5 Marking and operating instructions
5.1 Marking
In addition to IEC 61557-1:2019, 5.1 and 5.2, the following information shall be provided on
the measuring equipment:
– open-circuit voltage;
– measuring current;
– the nominal system voltages for which the equipment has been rated;
– the measuring range in accordance with 4.5;
– rated voltage to earth and measurement category.
5.2 Operating instructions
In addition to IEC 61557-1:2019, 5.3, the following information shall be provided in the
operating instructions for the measuring equipment:
– a warning stating that measurements shall only be carried out on de-energized circuits;
– a warning stating that the results of measurements can be adversely affected by
impedances of additional operating circuits connected in parallel or by transient currents;
– a statement on the correct operation when power is supplied by a hand-driven generator;
– for measuring equipment powered by batteries/rechargeable cells, the possible number of
measurements shall be stated;
– for measuring equipment using DC voltage where the measured values of both polarities
are indicated, a statement about the interpretation of the results, if they are different.
6 Tests
6.1 General
In addition to IEC 61557-1:2019, Clause 6, the following tests shall be performed.
6.2 Operating uncertainty
The operating uncertainty shall be determined in accordance with Table 1. In this process, the
intrinsic uncertainties shall be determined under the following reference conditions:
– nominal value of the supply voltage;
– nominal r/min when power is supplied by a hand-driven generator;
– reference temperature 23 °C ± 2 °C;
– reference position in accordance with the manufacturer's statement.
The maximum operating uncertainty within the measuring range to be marked or stated shall
not exceed ±30 %, with the measured value as fiducial value determined in accordance
with Table 1.

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– 8 – IEC 61557-4:2019 © IEC 2019
Table 1 – Calculation of operating uncertainty
Requirements
Intrinsic
Reference conditions or Designation or tests in accordance Type of
uncertainty or
specified operating range code with relevant parts of test
influence quantity
IEC 61557
Intrinsic uncertainty Reference conditions A IEC 61557-4:2019, 6.2 R
Position Reference position ±90° E IEC 61557-1:2019, 4.2 R
1
approximately
Supply voltage At the limits stated by the E IEC 61557-1:2019, 4.2, 4.3 R
2
manufacturer
Temperature 0 °C and 35 °C E IEC 61557-1:2019, 4.2 T
3
(± 2°)
Operating IEC 61557-4:2019, 4.5 R
4
22

BA=±+ E
∑ i
uncertainty
i
3
Key
B
B% =±×100 %

A = intrinsic uncertainty
F
E = variations
i
R = routine test
T = type test
F = fiducial value

6.3 Open-circuit voltage
The lower value of open-circuit voltage shall be measured and compliance with the
requirements under 4.2 shall be tested (type test).
The upper value of open-circuit voltage shall be measured and compliance with the
requirements under 4.2 shall be tested (type test).
6.4 Measuring current
The measuring current shall be measured and compliance with the requirement under 4.3
shall be tested (routine test).
6.5 Indication of limits
Compliance with the requirements under 4.7 shall be tested (type test).
6.6 Overvoltage
The permissible overload in accordance with 4.8 shall be tested.
For this purpose, an AC voltage of 1,2 times the amplitude of the nominal voltage of the
distribution system shall be applied in succession for a duration of at least 10 s to each of the
measurement terminals. The test shall be performed with the measuring equipment switched
on and off. After this, the measuring equipment shall not be damaged (type test).
After tests with AC overvoltage, defects, if any, shall be clearly indicated. Indications and
displayed values shall not lead to unsafe interpretations.
After tests with AC overvoltages, the equipment shall stay within the specification. This
includes reactivation of protective devices by the user without any repair.

---------------------- Page: 10 ----------------------
IEC 61557-4:2019 © IEC 2019 – 9 –
The replacement of fuses accessible to the user should be considered as reactivation of a
protective device.
Instead of an AC voltage, a DC voltage 1,5 times the AC voltage with sequential polarity
change may be used.
6.7 Battery life in battery operated instruments
In this process, the measuring equipment shall be loaded with a test resistance of
(1 Ω ± 5 mΩ) using a duty cycle of at least 5 s measurement time and an interval of
approximately 25 s between measurements (type test).

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– 10 – IEC 61557-4:2019 © IEC 2019
Bibliography
IEC 61010-1:2010, Safety requirements for electrical equipment for measurement, control,
and laboratory use – Part 1: General requirements
1
IEC 61010-1:2010/AMD1:2016

___________

__________
1
A consolidated version of this publication exists, comprising IEC 61010-1:2010 and
IEC 61010-1:2010/AMD1:2016.

---------------------- Page: 12 ----------------------
– 12 – IEC 61557-4:2019 © IEC 2019
SOMMAIRE
AVANT-PROPOS . 13
1 Domaine d'application . 15
2 Références normatives . 15
3 Termes et définitions . 15
4 Exigences . 15
4.1 Généralités . 15
4.2 Tension de mesure . 16
4.3 Courant de mesure . 16
4.4 Mesure avec une tension continue . 16
4.5 Etendue de mesure . 16
4.6 Résistance externe . 16
4.7 Indication des limites . 16
4.8 Surtension . 17
5 Marquage et instructions de fonctionnement . 17
5.1 Marquage . 17
5.2 Instructions de fonctionnement . 17
6 Essais . 17
6.1 Généralités . 17
6.2 Incertitude de fonctionnement . 17
6.3 Tension en circuit ouvert . 18
6.4 Courant de mesure . 18
6.5 Indication des limites . 18
6.6 Surtension . 18
6.7 Durée de vie des batteries des instruments fonctionnant sur batterie . 19
Bibliographie . 20

Tableau 1 – Calcul de l'incertitude de fonctionnement . 18

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IEC 61557-4:2019 © IEC 2019 – 13 –
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________

SÉCURITÉ ÉLECTRIQUE DANS LES RÉSEAUX DE DISTRIBUTION
BASSE TENSION AU PLUS ÉGALE À 1 000 V C.A. ET 1 500 V C.C. –
DISPOSITIFS DE CONTRÔLE, DE MESURE OU DE SURVEILLANCE
DE MESURES DE PROTECTION –

Partie 4: Résistance de conducteurs de terre
et d'équipotentialité

AVANT-PROPOS
1) La Commission Electrotechnique Internationale (IEC) est une organisation mondiale de normalisation
composée de l'ensemble des comités électrotechniques nationaux (Comités nationaux de l'IEC). L'IEC a pour
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...

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