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

IEC 61557-1:2019 is available as IEC 61557-1:2019 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 61557-1:2019 specifies the general requirements applicable to measuring and monitoring equipment for testing the electrical safety in low-voltage distribution systems with nominal voltages up to 1 000 V AC and 1 500 V DC. When measuring equipment or measuring installations involve measurement tasks of various measuring equipment covered by this series of standards, then the part of this series relevant to each of the measurement tasks is applicable. Other parts of IEC 61557 can specify additional requirements or deviations. This document does not cover functional safety or cybersecurity. IEC 61557-1:2019 cancels and replaces the second edition published in 2007. This edition constitutes a technical revision. This third edition includes the following significant technical changes with respect to the previous edition:
a) terms aligned with IEC 60050;
b) measurement of uncertainty revised according to the equations in 4.2 of ISO/IEC Guide 98-3:2008 (GUM);
c) updated references for safety and EMC requirements;
d) updated references for marking and operating instructions;
e) updated references for testing safety and EMC;
f) Annex A contains an explanation of GUM;
g) Annex B addresses environmental aspects.

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 1: Exigences générales

IEC 61557-1:2019 est disponible sous forme de IEC 61557-1:2019 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.
L'IEC 61557-1:2019 spécifie les exigences générales applicables aux dispositifs de mesure et de surveillance utilisés aux fins d'essai de la sécurité électrique dans les réseaux de distribution basse tension au plus égale à 1 000 V c.a. et 1 500 V c.c. Lorsque des appareils ou installations de mesure impliquent des mesures avec différents appareils couverts par la présente série de normes, la partie de cette série de normes qui est pertinente pour un type de mesure donné est applicable. Les autres parties de l'IEC 61557 peuvent spécifier des exigences supplémentaires ou des écarts. La présente norme ne couvre pas la sécurité fonctionnelle ou la cybersécurité. L'IEC 61557-1:2019 annule et remplace la deuxième édition parue en 2007. Cette édition constitue une révision technique. Cette troisième édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) alignement des termes sur ceux de l'IEC 60050;
b) mesure de l'incertitude revue conformément aux équations données en 4.2 du Guide ISO/IEC 98-3:2008 (GUM);
c) mise à jour des références aux exigences de sécurité et de CEM;
d) mise à jour des références au marquage et aux instructions de fonctionnement;
e) mise à jour des références aux essais de sécurité et de CEM;
f) l'Annexe A comporte une explication du GUM;
g) l'Annexe B porte sur les aspects environnementaux.

General Information

• Status: Published
• Publication Date: 25-Jul-2019
• ICS: 17.220.20 - Measurement of electrical and magnetic quantities
• ICS: 29.080.01 - Electrical insulation in general
• ICS: 29.240.01 - Power transmission and distribution networks in general
• Technical Committee: TC 85 - Measuring equipment for electrical and electromagnetic quantities
• Drafting Committee: WG 8 - TC 85/WG 8
• Current Stage: PPUB - Publication issued
• Start Date: 09-Aug-2019
• Completion Date: 26-Jul-2019

Standards Content (Sample)

IEC 61557-1
®

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 1: General requirements

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 1: Exigences générales
IEC 61557-1:2019-07(en-fr)

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IEC 61557-1

®


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 1: General requirements



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 1: Exigences générales










INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 17.220.20; 29.080.01; 29.240.01 ISBN 978-2-8322-7141-4




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 61557-1:2019 © IEC 2019
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Requirements . 12
4.1 General requirements . 12
4.2 Influence quantities – Operating uncertainty (B), percentage operating
uncertainty (B [%]) . 12
4.3 Rated operating conditions . 13
4.4 Battery test facility . 14
4.5 Safety . 14
4.6 Electromagnetic compatibility . 14
4.6.1 Immunity . 14
4.6.2 Emission . 14
4.7 Mechanical strength against vibration . 14
5 Marking and operating instructions . 15
5.1 General . 15
5.2 Marking . 15
5.3 Operating instructions . 15
5.3.1 Performance requirements . 15
5.3.2 Other information . 15
6 Tests . 16
6.1 General . 16
6.2 Operating uncertainty . 16
6.2.1 General . 16
6.2.2 Influence of changing position . 16
6.2.3 Influence of temperature . 16
6.2.4 Influence of the supply voltage . 16
6.3 Battery test facility . 16
6.4 Safety tests . 16
6.5 EMC tests . 16
6.6 Mechanical requirements . 17
6.7 Marking and operating instructions . 17
6.8 Records . 17
Annex A (informative) Explanation of the application of GUM in series IEC 61557 . 18
A.1 Overview. 18
A.2 Basic model of evaluation of results under operational conditions . 18
A.2.1 General . 18
A.2.2 Standard uncertainty of a result . 18
A.2.3 Expanded uncertainty . 19
A.2.4 Relative operating uncertainty . 19
A.2.5 Calibration uncertainty . 19
A.3 Operating uncertainty calculations as basis for 4.1 . 20
A.3.1 Standard uncertainty . 20
A.3.2 Operating uncertainty in accordance with 4.1 . 20

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IEC 61557-1:2019 © IEC 2019 – 3 –
Annex B (informative) Environmental aspects . 21
B.1 Overview. 21
B.2 Guidelines to establish a material declaration and end-of-life information . 21
B.2.1 General . 21
B.2.2 Guidelines for material declaration . 22
B.2.3 Guidelines for end-of-life (EoL) . 22
B.2.4 Example of a material declaration and end-of-life information . 22
Bibliography . 25

Figure B.1 – Components listed for EoL of a product . 24

Table B.1 – Material content according to IEC 62474 material classes . 23

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– 4 – IEC 61557-1:2019 © IEC 2019
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 1: General requirements

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
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6) All users should ensure that they have the latest edition of this publication.
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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 61557-1 has been prepared by 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 third edition includes the following significant technical changes with respect to the
previous edition:
a) terms aligned with IEC 60050;
b) measurement of uncertainty revised according to the equations in 4.2 of
ISO/IEC Guide 98-3:2008 (GUM);
c) updated references for safety and EMC requirements;

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IEC 61557-1:2019 © IEC 2019 – 5 –
d) updated references for marking and operating instructions;
e) updated references for testing safety and EMC;
f) Annex A contains an explanation of GUM;
g) Annex B addresses environmental aspects.
The text of this International Standard is based on the following documents:
FDIS Report on voting
85/689/FDIS 85/692/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.
A list of all parts in 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.

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– 6 – IEC 61557-1:2019 © IEC 2019
INTRODUCTION
IEC 60364-6 stipulates standardized conditions for the initial test of power installations
in TN, TT or IT systems for continuous monitoring and for testing these installations after
modifications. In addition to general references for the performance of the tests, IEC 60364-6
contains requirements that have to be verified by measurements. Only in a few instances, for
example when measuring the insulation resistance, does IEC 60364-6 contain details of the
characteristics of the measuring device to be used. Circuits which are given as examples in
IEC 60364-6, and referred to within the text of that document, are generally not suitable for
practical use.
The tests are carried out in installations where hazardous voltages can occur and where
careless use or a defect in the equipment can easily cause an accident. Therefore, the
technician has to rely on measuring devices which ensure safe test methods, in addition to
simplifying the measurements.
The application of the general safety regulations for electrical and electronic measuring
devices (IEC 61010-1) for testing the protective measures is not sufficient in itself. The
performance of measurements in the installation can cause hazards not only to the technician,
but also to third persons, depending on the measuring method used.
Likewise, reliable and comparable results of measurement with measuring devices from
different manufacturers are an important precondition in order to obtain an objective
assessment about the installation, for example when the installation is handed over for
periodic tests, for continuous insulation monitoring or in the case of performance warranty.
The IEC 61557 series has been established with the aim of stipulating common principles for
measuring and monitoring equipment for testing electrical safety and measuring performances
in systems with nominal voltages up to 1 000 V AC and 1 500 V DC which correspond to the
above-mentioned characteristics.
For that reason, the following common requirements have been stipulated in IEC 61557-1
(other parts of IEC 61557 can specify additional requirements or deviations):
– protection against extraneous voltages;
– class II protection (except insulation monitoring devices and insulation fault location
systems);
– requirements and safety precautions against hazardous touch voltages at the measuring
device;
– requirements for the assessment of connection configurations with respect to wiring errors
in the tested equipment;
– special mechanical requirements;
– measuring methods;
– measured quantity;
– specification of the maximum operating uncertainty;
– requirements for testing the influencing quantity and the calculation of the operating
uncertainty;
– uncertainties of the measuring device at the thresholds specified in the respective
standards;
– specification of the nature of type and routine tests and the required conditions for testing.
Contrary to the usual convention, terms and definitions that occur more than once in another
part of the series are listed in IEC 61557-1:2019, Clause 3. Only terms and definitions specific
to the respective part of IEC 61557 are listed in Clause 3 of that part.

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IEC 61557-1:2019 © IEC 2019 – 7 –
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



1 Scope
This part of IEC 61557 specifies the general requirements applicable to measuring and
monitoring equipment for testing the electrical safety in low-voltage distribution systems with
nominal voltages up to 1 000 V AC and 1 500 V DC.
When measuring equipment or measuring installations involve measurement tasks of various
measuring equipment covered by this series of standards, then the part of this series relevant
to each of the measurement tasks is applicable.
NOTE The term "measuring equipment" will hereafter be used to designate "testing, measuring and monitoring
equipment".
Other parts of IEC 61557 can specify additional requirements or deviations.
This document does not cover functional safety or cybersecurity.
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 60038:2009, IEC standard voltages
IEC 60529:1989, Degrees of protection provided by enclosures (IP code)
IEC 60529:1989/AMD1:1999
1
IEC 60529:1989/AMD2:2013
IEC 61010-1:2010, Safety requirements for electrical equipment for measurement, control and
laboratory use – Part 1: General requirements
2
IEC 61010-1:2010/AMD1:2016
IEC 61010-031, Safety requirements for electrical equipment for measurement, control and
laboratory use – Part 031: Safety requirements for hand-held and hand-manipulated
assemblies for electrical test and measurement
__________
1
 A consolidated version of this publication exists, comprising IEC 60529:1989, IEC 60529:1989/AMD1:1999 and
IEC 60529:1989/AMD2:2013.
2
 A consolidated version of this publication exists, comprising IEC 61010-1:2010 and
IEC 61010-1:2010/AMD 1:2016.

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– 8 – IEC 61557-1:2019 © IEC 2019
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 61010-2-032, Safety requirements for electrical equipment for measurement, control, and
laboratory use – Part 2-032: Particular requirements for hand-held and hand-manipulated
current sensors for electrical test and measurement
IEC 61010-2-034:2017, Safety requirements for electrical equipment for measurement, control,
and laboratory use – Part 2-034: Particular requirements for measurement equipment for
insulation resistance and test equipment for electric strength
IEC 61326-1:2012, Electrical equipment for measurement, control and laboratory use – EMC
requirements – Part 1: General requirements
IEC 61557-8:2014, 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 8:
Insulation monitoring devices for IT systems
IEC 61557-9:2014, 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 9:
Equipment for insulation fault location in IT systems
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
3.1
nominal system voltage
U
n
value of the voltage by which the distribution system is designated and to which certain
characteristics are assigned
3.2
voltage against earth
U
o
voltage between a phase conductor
and the earthed neutral point
3.3
voltage against earth
U
o
voltage present between the remaining phase conductors
and earth when one of the phase conductors is short-circuited to earth
3.4
fault voltage
U
f
voltage between a given point of fault and reference earth resulting from an insulation fault
[SOURCE: IEC 60050-826:2004, 826-11-02, modified – The symbol has been added.]

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IEC 61557-1:2019 © IEC 2019 – 9 –
3.5
effective touch voltage
U
t
voltage between conductive parts when touched simultaneously by a person or an animal
Note 1 to entry: The value of the effective touch voltage may be appreciably influenced by the impedance of the
person or the animal in electric contact with these conductive parts.
[SOURCE: IEC 60050-195:1998, 195-05-11, modified – The symbol has been added.]
3.6
conventional touch voltage limit
U
L
maximum value of the touch voltage which is permitted to be maintained indefinitely in
specified conditions of external influences and is usually equal to 50 V AC, RMS or 120 V
ripple free DC
[SOURCE: IEC 60050-826:2004, 826-11-04, modified – "prospective" has been omitted from
the term and from the definition and values for the limit have been added to the definition; the
symbol has been added.]
3.7
supply voltage
voltage that is used to power the measurement equipment
Note 1 to entry: If a supply voltage is specified, for instance in the supply contract, then it is called "declared
supply voltage".
3.8
rated supply voltage
U
S
value of the supply voltage at a point where the measuring equipment does or can accept
electric energy as a supply
3.9
output voltage
U
a
voltage across the measuring equipment terminals where this equipment does or can output
electric energy
3.10
open-circuit voltage
U
q
voltage present across unloaded terminals on the measuring equipment
3.11
rated voltage
U
N
voltage value assigned by a manufacturer or other entity for a specified operating condition of
the measuring equipment
Note 1 to entry: The value for the rated voltage of low-voltage equipment is generally assigned from the list of
nominal voltages in IEC 60038:2009, Tables 1 and 6.
Note 2 to entry: Equipment may have more than one rated voltage value or may have a rated voltage range.
[SOURCE: IEC 60050-614:2016, 614-03-09, modified – The domain and
Note 1 have been omitted; the symbol has been added; the term specifically adapted for
measuring equipment.]

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– 10 – IEC 61557-1:2019 © IEC 2019
3.12
extraneous voltage
external voltage to which the measuring equipment can be subjected during measurement
3.13
rated current

I
N
current assigned by the manufacturer for the specified operating condition of the measuring
equipment
Note 1 to entry: The specified operating condition is a value (or values) within the rated operating conditions that
are designated by the manufacturer.
[SOURCE: IEC 60050-442:1998, 442-01-02, modified – "for accessories" has been deleted
from the term and Note 1 has been added; the definition has been adapted for application to
measuring equipment.]
3.14
short-circuit current
over-current resulting from a short circuit due to a fault on the terminals or within the
measuring equipment
3.15
rated frequency
f
N
frequency for which the measuring equipment is intended to be used and for which it has
been designed
3.16
uncertainty of
...