IEC 61557-4:2019

IEC 61557-4 ®
Edition 3.0 2019-07
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
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

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IEC 61557-4 ®
Edition 3.0 2019-07
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
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

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 17.220.20; 29.080.01; 29.240.01 ISBN 978-2-8322-7234-3

– 2 – IEC 61557-4:2019 RLV © 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 . 7
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 . 8
6.3 Open-circuit voltage . 8
6.4 Measuring current . 8
6.5 Indication of limits . 9
6.6 Overvoltage . 9
6.7 Battery life in battery operated instruments . 9
Bibliography . 10

Table 1 – Calculation of operating uncertainty . 8

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
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– 4 – IEC 61557-4:2019 RLV © IEC 2019
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;
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.
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.

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
The fo
...