IEC 61557-16:2023

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 16: Equipment for testing the effectiveness of the protective measures of electrical equipment and/or medical electrical equipment

IEC 61557-16:2023 specifies the requirements applicable to the performance for test and measurement equipment in order to determine the effectiveness of the protective measures for electrical equipment and/or medical electrical equipment described in IEC 62353.
This International Standard is to be used in conjunction with IEC 61557-1:2019.
IEC 61557-16:2023 cancels and replaces the first edition published in 2014. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) splitting of uncertainty requirements for medical and non-medical electrical equipment in 4.2.1;
b) addition of a definition of ranges with defined uncertainty in 4.2.1 to 4.2.7;
c) addition of an optional measuring device (MD) for non-medical devices in 4.2.1;
d) addition of a limitation of the maximum intrinsic uncertainty for medical applications at leakage current in 4.2.1;
e) change of 4.2.3 from test sockets to sockets for service purposes;
f) addition of a warning in the operating instructions;
g) integration of former 6.3 into 6.2;
h) update of Table 1;
i) 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 en courant alternatif et 1 500 V en courant continu - Dispositifs de contrôle, de mesure ou de surveillance de mesures de protection - Partie 16: Équipement pour les essais de bon fonctionnement des mesures de protection des appareils électriques et/ou des appareils électromédicaux

L'IEC 61557-16:2023 spécifie les exigences de performance applicables pour les dispositifs de contrôle et de mesure afin de déterminer le bon fonctionnement des mesures de protection des appareils électriques et/ou des appareils électromédicaux décrits dans l’IEC 62353.
L'IEC 61557-16:2023 annule et remplace la première édition parue en 2014. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l’édition précédente:
a) séparation des exigences d’incertitude pour les appareils électromédicaux et électriques non médicaux en 4.2.1;
b) ajout d’une définition de plages avec une incertitude définie de 4.2.1 à 4.2.7;
c) ajout d’un dispositif de mesure (DM) facultatif pour les appareils non médicaux en 4.2.1;
d) ajout d’une limitation de l’incertitude intrinsèque maximale pour les applications médicales au niveau du courant de fuite en 4.2.1;
e) changement en 4.2.3 de "prises de courant d’essai" en "prises de courant pour des besoins de service";
f) ajout d’un avertissement dans les instructions de fonctionnement;
g) intégration de l’ancien 6.3 en 6.2;
h) mise à jour du Tableau 1;
i) alignement de la structure sur celle de l’ensemble de la série IEC 61557.

General Information

• Status: Published
• Publication Date: 24-Aug-2023
• ICS: 17.220.20 - Measurement of electrical and magnetic quantities
• ICS: 29.080.01 - Electrical insulation 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: 18-Aug-2023
• Completion Date: 25-Aug-2023

Relations

• Revises: IEC 61557-16:2014 - 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 16: Equipment for testing the effectiveness of the protective measures of electrical equipment and/or medical electrical equipment
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61557-16
®

Edition 2.0 2023-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


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 16: Equipment for testing the effectiveness of the protective measures of
electrical equipment and/or medical electrical equipment

Sécurité électrique dans les réseaux de distribution basse tension au plus égale
à 1 000 V en courant alternatif et 1 500 V en courant continu – Dispositifs de
contrôle, de mesure ou de surveillance de mesures de protection –
Partie 16: Équipement pour les essais de bon fonctionnement des mesures de
protection des appareils électriques et/ou des appareils électromédicaux
IEC 61557-16:2023-08(en-fr)

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---------------------- Page: 2 ----------------------
IEC 61557-16

®


Edition 2.0 2023-08




INTERNATIONAL



STANDARD




NORME


INTERNATIONALE











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 16: Equipment for testing the effectiveness of the protective measures of

electrical equipment and/or medical electrical equipment




Sécurité électrique dans les réseaux de distribution basse tension au plus

égale à 1 000 V en courant alternatif et 1 500 V en courant continu – Dispositifs

de contrôle, de mesure ou de surveillance de mesures de protection –


Partie 16: Équipement pour les essais de bon fonctionnement des mesures de

protection des appareils électriques et/ou des appareils électromédicaux







INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE





ICS 17.220.20, 29.080.01 ISBN 978-2-8322-7251-0




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

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– 2 – IEC 61557-16:2023 © IEC 2023
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Requirements . 9
4.1 General requirements . 9
4.2 Measuring functions . 9
4.2.1 Minimum measuring function requirements . 9
4.2.2 Measurement of the resistance of the protective bonding or the
protective earth resistance . 10
4.2.3 Measurement of insulation resistance . 10
4.2.4 Measurement of protective conductor current or equipment leakage
current with the alternative method . 11
4.2.5 Measurement of touch current, patient leakage current and applied part
leakage current with the alternative method . 11
4.2.6 Measurement of protective conductor current and equipment leakage
current with the direct or differential (residual) method . 12
4.2.7 Measurement of touch current, patient leakage current and applied part
leakage current with the direct or differential (residual) method . 13
4.3 Construction requirements . 13
4.3.1 Overvoltage capability . 13
4.3.2 Terminals . 13
4.3.3 Sockets for service purpose . 14
4.3.4 Degree of protection . 14
4.3.5 Class of protection . 14
4.3.6 Overvoltage and measurement categories . 14
4.3.7 Accessories . 14
5 Markings and operating instructions . 15
5.1 Markings . 15
5.2 Operating instructions . 15
6 Tests . 15
6.1 General . 15
6.2 Operating uncertainty . 15
6.3 Tests of measuring circuits according to measuring functions . 18
6.4 Test of construction requirements of test and measurement equipment . 18
Annex A (normative) Measuring circuit MD . 19
A.1 Current measuring circuit MD . 19
A.2 Frequency characteristic of current measuring circuit MD . 20
Bibliography . 21

Figure A.1 – Current measuring circuit MD . 19
Figure A.2 – Frequency characteristic of the current measuring circuit MD . 20

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IEC 61557-16:2023 © IEC 2023 – 3 –
Table 1 – Calculation of operating uncertainty for leakage measurements with direct or
differential method . 17
Table 2 – Compliance tests of measuring circuits according to measuring function . 18
Table 3 – Compliance test of construction requirements of test and measuring
equipment . 18

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– 4 – IEC 61557-16:2023 © IEC 2023
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 16: Equipment for testing the effectiveness of the protective
measures of electrical equipment and/or medical electrical equipment

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
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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.
IEC 61557-16 has been prepared by IEC technical committee 85: Measuring equipment for
electrical and electromagnetic quantities. It is an International Standard.
This second edition cancels and replaces the first edition published in 2014. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) splitting of uncertainty requirements for medical and non-medical electrical equipment in
4.2.1;
b) addition of a definition of ranges with defined uncertainty in 4.2.1 to 4.2.7;
c) addition of an optional measuring device (MD) for non-medical devices in 4.2.1;

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IEC 61557-16:2023 © IEC 2023 – 5 –
d) addition of a limitation of the maximum intrinsic uncertainty for medical applications at
leakage current in 4.2.1;
e) change of 4.2.3 from test sockets to sockets for service purposes;
f) addition of a warning in the operating instructions;
g) integration of former 6.3 into 6.2;
h) update of Table 1;
i) alignment of the structure with that of the whole IEC 61557 series.
The text of this International Standard is based on the following documents:
Draft Report on voting
85/876/FDIS 85/885/RVD

Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
This International Standard is to be used in conjunction with IEC 61557-1:2019.
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 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 61557-16:2023 © IEC 2023
INTRODUCTION
This part of IEC 61557 defines performance requirements of measuring equipment intended for
testing the effectiveness of the protective measures of either electrical equipment or medical
electrical equipment, or both (in accordance with IEC 62353). It is the intention of this document
to achieve comparable measuring results, additional safety for the person carrying out the
testing, and non-damaging electrical stress for the unit under test.

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IEC 61557-16:2023 © IEC 2023 – 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 16: Equipment for testing the effectiveness of the protective
measures of electrical equipment and/or medical electrical equipment



1 Scope
This part of IEC 61557 specifies the requirements applicable to the performance for test and
measurement equipment in order to determine the effectiveness of the protective measures for
electrical equipment and/or medical electrical equipment described in IEC 62353.
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 60529, Degrees of protection provided by enclosures (IP Code)
IEC 60601-1:2005, Medical electrical equipment – Part 1: General requirements for basic safety
and essential performance
IEC 60601-1:2005/AMD1:2012
IEC 60601-1:2005/AMD2:2020
IEC 61010-1:2010, Safety requirements for electrical equipment for measurement, control, and
laboratory use – Part 1: General requirements
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 probe
assemblies for electrical test and measurement
IEC 61010-2-030, 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, 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 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

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– 8 – IEC 61557-16:2023 © IEC 2023
IEC 61557-2, 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 2:
Insulation resistance
IEC 61557-4, 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 61557-10, 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 10:
Combined measuring equipment for testing, measuring or monitoring of protective measures
IEC 61557-13, 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 13:
Hand-held and hand-manipulated current clamps and sensors for measurement of leakage
currents in electrical distribution systems
IEC 62353:2014, Medical electrical equipment – Recurrent test and test after repair of medical
electrical equipment
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61557-1, IEC 61557-2,
IEC 61557-4, IEC 61557-10 and IEC 61557-13, and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1
test socket outlet
socket outlet on the test equipment that can be switched to either test-condition or supply
condition
3.2
service socket
socket outlet on the test equipment to supply mains to further test equipment or additional
equipment
3.3
measuring circuit MD
electric circuit with defined components and defined frequency characteristic
3.4
peak factor
ratio of the maximum absolute value of an alternating quantity to its RMS value
[SOURCE: IEC 60050-103:2017, 103-06-15, modified – Note to entry omitted.]
3.5
medical electrical equipment
ME equipment
electrical equipment having an applied part or transferring energy to or from the patient or
detecting such energy transfer to or from the patient and which is:

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IEC 61557-16:2023 © IEC 2023 – 9 –
a) provided with not more than one connection to a particular supply mains, and
b) intended by its manufacturer to be used:
– in the diagnosis, treatment, or monitoring of a patient, or
– for compensation or alleviation of disease, injury or disability
Note 1 to entry: ME equipment includes those accessories as defined by the manufacturer that are necessary to
enable the normal use of the ME equipment.
Note 2 to entry: Not all electrical equipment used in medical practice falls within this definition (e.g. some in vitro
diagnostic equipment).
Note 3 to entry: The implantable parts of active implantable medical devices can fall within this definition, but they
are excluded from the scope of IEC 60601-1 by appropriate wording in IEC 60601-1:2005, Clause 1,
IEC 60601-1:2005/AMD1:2012, Clause 1, and IEC 60601-1:2005/AMD2:2020, Clause 1.
[SOURCE: IEC 60601-1:2005, 3.63, modified – Notes 4 and 5 deleted.]
3.6
protective earth resistance
resistance between any accessible conductive part which has to be connected for safety
purposes to the protective earth terminal and the
– protective connector of the mains plug, or
– protective connector of the appliance inlet, or
– protective conductor permanently connected to the supply mains;
resistance between protective connectors at each end of a detachable power supply cord
[SOURCE: IEC 62353:2014, 3.34]
4 Requirements
4.1 General requirements
In addition to the requirements of IEC 61557-1:2019, Clause 4, the following requirements shall
apply.
The requirements of IEC 62353:2014, Annex C shall apply for measuring equipment intended
for medical electrical equipment testing.
Equipment intended for making measurements on electrical equipment shall be rated for
minimum measurement category II in accordance with IEC 61010-2-030.
Insulation measurement equipment shall fulfil the safety requirements of IEC 61010-2-034.
Test leads and test probes used with the measuring equipment shall fulfil the requirements of
IEC 61010-031.
4.2 Measuring functions
4.2.1 Minimum measuring function requirements
The measuring equipment shall be capable of measuring the following quantities as a minimum:
– resistance of protective bonding and/or protective earth resistance,
– insulation resistance,
– protective conductor current and/or equipment leakage current,
– touch current,

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– 10 – IEC 61557-16:2023 © IEC 2023
– applied part leakage current for measuring equipment intended for medical electrical
equipment testing (IEC 62353).
The operating uncertainty for all measured parameters within the required ranges at the
applicable limits according to IEC 62353 shall be ±15 % at the maximum. For measurement of
protective conductor current, equipment leakage current, touch current and applied part leakage
current the operating uncertainty shall be determined at a frequency of 50/60 Hz. The frequency
characteristic for higher frequency ranges is given by the MD circuit according to Figure A.1
and Figure A.2.
Leakage currents for medical electrical equipment shall be measured using a measuring circuit
MD with the characteristics defined in Clause A.1 and Clause A.2. Leakage currents for
non-medical electrical equipment may be tested using a measuring circuit MD in accordance
with IEC 61010-1:2010, Clause A.1.
For medical electrical equipment, the maximum intrinsic uncertainty for leakage current
measurements shall be ±5 %.
NOTE If the measuring equipment evaluates a limit, for example 3,5 mA, the maximum applicable uncertainty can
be taken into account, for example ± 15 %. This means that only measurements less than or equal to 2,97 mA can
pass the test.
The operating uncertainty shall be determined in accordance with IEC 61557-1 with the
influence quantities E , E , E , E modified, E , E , and, if applicable, E , E , E in
1 2 3 9 11 12 13 14 15
accordance with IEC 61557-13.
4.2.2 Measurement of the resistance of the protective bonding or the protective earth
resistance
The measuring equipment shall be in accordance with IEC 61557-4. The withstand capability
against extraneous voltages is not required if the test and measurement equipment is not
intended to be used on fixed installed or permanently connected equipment.
To prevent damage to the equipment under test it is recommended to select a test current not
exceeding 1 A.
The measuring circuit shall be separated from the active parts of mains by double or reinforced
insulation in accordance with IEC 61010-1. The protective conductor may be connected to the
measuring circuit, but parallel earth connections shall be indicated and/or taken into account
by the test and measurement equipment.
When external resistances are included in the calibration as a zero offset, this shall be indicated.
The indication shall continue as long as the calibration is valid.
The measuring range shall include the values between 0,05 Ω and 1,99 Ω and the display shall
have a minimum resolution of 0,01 Ω. Within the range of 0,1 Ω and 1,99 Ω, the measuring
current shall not be less than 0,2 A and the operating uncertainty shall be within the limits of
4.2.1.
Continuous measurements shall be possible for measuring currents below 5 A. For higher test
currents, limiting the test duration is allowed.
4.2.3 Measurement of insulation resistance
The measuring equipment shall be in accordance with IEC 61557-2. The withstand capability
against extraneous voltages is not required if the test and measurement equipment is not
intended to test fixed installed or permanently connected equipment.

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IEC 61557-16:2023 © IEC 2023 – 11 –
The
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