IEC 61557-13:2023

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 13: Hand-held and hand-manipulated current clamps and sensors for measurement of leakage currents in electrical distribution systems

IEC 61557-13:2023 defines special performance requirements for hand-held and hand manipulated current clamps and sensors for measurement of leakage currents in electrical distribution systems up to 1 000 V AC and 1 500 V DC taking into account the influence of high external low-frequency magnetic fields and other influencing quantities. See Annex A for examples of measurement applications.
This document does not apply to current clamps or sensors that are used in combination with devices for insulation fault location in accordance with IEC 61557-9, unless it is specified by the manufacturer.
IEC 61557-13:2023 cancels and replaces the first edition published in 2011. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) the term "fixing device" has been removed;
b) the measuring range was changed to a display range, the indication of DC or peak values has been added in 4.1;
c) the frequency for the test of sensitivity for low-frequency magnetic fields has been defined in 4.2;
d) the specified measuring range is now defined as the range of indicated values based on the operating uncertainty in 4.3;
e) alignment of the structure with that of the whole IEC 61557 series;
f) the variation E12 (maximum load current), may be specified according to the manufacturer’s specification.

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 13: Pinces et capteurs de courant portatifs et manipulés à la main pour la mesure des courants de fuite dans les réseaux de distribution électriques

L'IEC 61557-13:2023 définit les exigences spécifiques de qualités de fonctionnement relatives aux pinces et capteurs de courant portatifs et manipulés à la main, en vue de la mesure des courants de fuite dans les réseaux de distribution électriques jusqu'à 1 000 V en courant alternatif et 1 500 V en courant continu en prenant en compte l’influence des champs magnétiques externes à basse fréquence élevés et autres grandeurs d’influence. Voir l'Annexe A pour des exemples d'applications de mesure.
Le présent document ne s'applique pas aux pinces et capteurs de courant utilisés en association avec des dispositifs prévus pour la localisation des défauts d'isolement conformes à l'IEC 61557‑9, sauf spécification de la part du fabricant à ce sujet.
L'IEC 61557-13:2023 annule et remplace la première édition publiée en 2011. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) le terme "dispositif de fixation" a été supprimé;
b) la plage de mesure a été remplacée par une plage d'affichage, et l'indication des valeurs de courant continu ou des valeurs de crête a été ajoutée au 4.1;
c) la fréquence de l'essai de sensibilité aux champs magnétiques à basse fréquence a été définie au 4.2;
d) la plage de mesure spécifiée est désormais définie comme la plage des valeurs indiquées fondées sur l'incertitude de fonctionnement au 4.3;
e) alignement de la structure sur celle de toute la série IEC 61557;
f) la variation E12 (courant de charge maximal) peut être spécifiée selon la spécification du fabricant.

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
• 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: 25-Aug-2023
• Completion Date: 18-Aug-2023

Relations

• Revises: IEC 61557-13:2011 - 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 13: Hand-held and hand-manipulated current clamps and sensors for measurement of leakage currents in electrical distribution systems
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61557-13 ®
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 13: Hand-held and hand-manipulated current clamps and sensors for
measurement of leakage currents in electrical distribution systems

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 13: Pinces et capteurs de courant portatifs et manipulés à la main pour la
mesure des courants de fuite dans les réseaux de distribution électriques
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IEC 61557-13 ®
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 13: Hand-held and hand-manipulated current clamps and sensors for

measurement of leakage currents in electrical distribution systems

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 13: Pinces et capteurs de courant portatifs et manipulés à la main pour la

mesure des courants de fuite dans les réseaux de distribution électriques

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.220.20, 29.080.01, 29.240.01 ISBN 978-2-8322-7250-3

– 2 – IEC 61557-13:2023 © IEC 2023
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Requirements . 9
4.1 General requirements . 9
4.2 Operating classes . 9
4.2.1 General . 9
4.2.2 Operating class 1. 10
4.2.3 Operating class 2. 10
4.2.4 Operating class 3. 10
4.3 Operating uncertainty of the specified measuring range . 10
4.3.1 General . 10
4.3.2 Specified measuring range of an operating class 1 current sensor . 10
4.3.3 Specified measuring range of an operating class 2 current sensor . 11
4.3.4 Specified measuring range of an operating class 3 current sensor . 11
4.4 Reference conditions . 13
4.5 Mechanical requirements . 14
4.6 Pollution degree . 15
4.7 Measurement category . 15
4.8 Electromagnetic compatibility (EMC) . 15
5 Marking and operating instructions . 15
5.1 Marking . 15
5.2 Operating instructions . 15
6 Tests . 16
6.1 General . 16
6.2 Operating uncertainty . 16
6.3 Verification of the operating instructions . 18
6.4 Verification of the marking . 18
Annex A (informative) Examples of measurement applications . 19
Bibliography . 21

Figure 1 – Operating uncertainty in relation to operating class and external magnetic
field for measuring ranges less than or equal to 10 mA . 12
Figure 2 – Operating uncertainty in relation to operating classes and external magnetic
field and measuring ranges greater than 10 mA . 13
Figure 3 – Reference position for two straight conductors (differential method) . 14
Figure 4 – Example of operating positions for differential method . 14
Figure 5 – Example for an applicable pictogram for operating class 1 using caution
symbol ISO 7000-0434A:2004-01 . 15
Figure A.1 – Example for measurement of protective conductor current – Direct method . 19
Figure A.2 – Example for measurement of leakage current including protective
conductor current – Differential method . 20

Table 1 – Relation between external magnetic field and operating class . 11
Table 2 – Reference conditions . 13
Table 3 – Calculation of the operating uncertainty . 17

– 4 – IEC 61557-13:2023 © 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 13: Hand-held and hand-manipulated current clamps and sensors for
measurement of leakage currents in electrical distribution systems

FOREWORD
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IEC 61557-13 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 2011. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the term "fixing device" has been removed;

b) the measuring range was changed to a display range, the indication of DC or peak values
has been added in 4.1;
c) the frequency for the test of sensitivity for low-frequency magnetic fields has been defined
in 4.2;
d) the specified measuring range is now defined as the range of indicated values based on
the operating uncertainty in 4.3;
e) alignment of the structure with that of the whole IEC 61557 series;
f) the variation E (maximum load current), may be specified according to the
manufacturer’s specification.
The text of this International Standard is based on the following documents:
Draft Report on voting
85/877/FDIS 85/883/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 International Standard is to be used in conjunction with IEC 61557-1:2019.
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.
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 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.
– 6 – IEC 61557-13:2023 © IEC 2023
INTRODUCTION
During periodical inspections of electrical installations, it is increasingly difficult to carry out
measurements of insulation resistances with devices in accordance with IEC 61557-2 when
the installations cannot be switched off for long periods and when there are sensitive
appliances connected. Therefore, the measurement of leakage currents can provide additional
information about the safe or unsafe situation of an installation.
Furthermore, the user has the opportunity to place current clamps and sensors on different
points of the distribution system for troubleshooting nuisance tripping of RCDs, alarms of
RCMs and other problems caused by low-frequency leakage currents.
Unfortunately, the presence of high external magnetic fields has a big impact on the
performance of commonly used current clamps and sensors. High uncertainty and
non-repeatability of readings can lead to unsafe interpretations.
This document defines performance classes for current clamps and sensors in relationship to
ranges of high external magnetic fields and gives guidance to the user to choose the
appropriate measuring device for a given situation.
The hand-held and hand-manipulated current clamps and sensors can be stand-alone
instruments or accessories of instruments.

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

1 Scope
This part of IEC 61557 defines special performance requirements for hand-held and
hand-manipulated current clamps and sensors for measurement of leakage currents in
electrical distribution systems up to 1 000 V AC and 1 500 V DC taking into account the
influence of high external low-frequency magnetic fields and other influencing quantities. See
Annex A for examples of measurement applications.
This document does not apply to current clamps or sensors that are used in combination with
devices for insulation fault location in accordance with IEC 61557-9, unless it is specified by
the manufacturer.
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 61000-4-8, Electromagnetic compatibility (EMC) – Part 4-8: Testing and measurement
techniques – Power frequency magnetic field immunity test
IEC 61010-1, Safety requirements for electrical equipment for measurement, control, and
laboratory use – Part 1: General requirements
IEC 61010-2-032:2019, 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 61326-1:2020, Electrical equipment for measurement, control and laboratory use – EMC
requirements – Part 1: General requirements
IEC 61557-1:2019, Electrical safety in low voltage distribution systems up to 1 000 V AC and
1 500 V DC – Part 1: General requirements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61557-1 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

– 8 – IEC 61557-13:2023 © IEC 2023
3.1
hand-held current clamp and sensor
portable or hand-held device for measurement, display or for indication of types of leakage
currents in distribution systems without interruption of circuits
Note 1 to entry: For simplification, this term is replaced with the term "current sensors" throughout the document.
3.2
hand-manipulated current clamp and sensor
portable or hand-manipulated device for measurement, display or for indication of types of
leakage currents in distribution systems without interruption of circuits
Note 1 to entry: For simplification, this term is replaced with the term "current sensors" throughout the document.
3.3
measurement category
classification of testing and measuring circuits according to the type of mains to which they
are intended to be connected
[SOURCE: IEC 61010-2-030:2017, 3.5.101, modified – Note 1 removed.]
3.4
variation E
variation due to external low-frequency magnetic fields
3.5
variation E
variation due to load current during measurement using the differential method
Note 1 to entry: For the differential method, see Figure A.2.
3.6
variation E
variation due to touch current to earth caused by common mode voltage during
hand-manipulation
3.7
variation E
variation due to frequency
3.8
variation E
repeatability of the measurement readings
Note 1 to entry: The variation repeatability means that at least 10 (or maybe more) open/closed cycles are made
before taking a measurement reading.
3.9
operating class
performance class defining the influence of external low-frequency magnetic fields on the
current sensors
3.10
leakage current
current driven by active conductors of a distribution system and/or loads to earth and/or
protective conductors
3.11
load current
current flowing through the line conductor(s)
3.12
rated burden
value of the burden on which the accuracy requirements of a specification are based
[SOURCE: IEC 60050-321:1986, 321-01-26]
3.13
resolution
smallest change in the measurand, or quantity supplied, which causes a perceptible change in
the indication
[SOURCE: IEC 60050-311:2001, 311-03-10]
3.14
fiducial value
fiducial value used for reference is the measured value of the leakage current
4 Requirements
4.1 General requirements
In addition to the requirements of IEC 61557-1:2019, Clause 4, the following requirements
shall apply.
Current sensors according to this document shall be in accordance with IEC 61010-2-032.
Current sensors according to this document shall have the ability to indicate leakage currents
for a minimum range of either 1 mA to 10 A AC or 1 mA to 10 A DC (or both) and shall be
designed for a load current of at least 60 A. Multiple ranges are allowed.
The resolution shall be 0,1 mA AC or 0,1 mA DC, or higher.
The current values shall be indicated as RMS values. Additional indication of DC or peak
values are allowed.
The frequency range of the current sensors shall include a range from a minimum of 40 Hz up
to the third harmonic of the rated mains frequency.
For railway applications, a frequency range starting at 15 Hz is recommended.
For industrial applications, a frequency range up to 1 kHz is recommended.
For testing the leakage current of appliances, a measuring range starting at 0,1 mA with a
resolution of 0,01 mA is recommended.
4.2 Operating classes
4.2.1 General
Current sensors are classified into three operating classes according to their sensitivity for
low-frequency magnetic fields in accordance with IEC 61000‑4‑8 at 50 Hz and 60 Hz.

– 10 – IEC 61557-13:2023 © IEC 2023
For optional frequency ranges between 16,7 Hz and 400 Hz, the test configuration in
accordance with IEC 61000‑4‑8 shall be used.
4.2.2 Operating class 1
Current sensors of operating class 1 shall operate within external low-frequency magnetic
fields according to 4.2.1 up to a field strength of 100 A/m.
The upper limit of field strength shall be marked in accordance with Figure 5.
4.2.3 Operating class 2
Current sensors of operating class 2 shall operate within external low-frequency magnetic
fields according to 4.2.1 up to a field strength of 30 A/m.
The upper limit of field strength shall be marked in accordance with Figure 5.
4.2.4 Operating class 3
Current sensors of operating class 3 shall operate within external low-frequency magnetic
fields according to 4.2.1 up to a field strength of 10 A/m.
The upper limit of field strength shall be marked in accordance with Figure 5.
4.3 Operating uncertainty of the specified measuring range
4.3.1 General
The operating uncertainty of the specified measuring range for current sensors of operating
class 1, operating class 2 and operating class 3 shall be determined according to the
operating uncertainty equation (1) of Table 3 within the reference conditions or specified
operating range. The relation between operating class and external magnetic field is shown in
Figure 1, Figure 2 and Table 1.
The fiducial value is the measured value of the leakage current.
4.3.2 Specified measuring range of an operating class 1 current sensor
The specified measuring range of an operating class 1 current sensor is the range of
indicated values between stated lower and upper measurements for which the operating
uncertainty of reading is:
– less than 15 % for values less than or equal to 10 mA, and is less than 10 % for values
greater than 10 mA for external low-frequency magnetic fields of up to 10 A/m;
and
– less than 20 % for values less than or equal to 10 mA and is less than 12,5 % for values
greater than 10 mA for external low-frequency magnetic fields of up to 30 A/m;
and
– less than 30 % for values less than or equal to 10 mA, and is less than 15 % for values
greater than 10 mA for external low-frequency magnetic fields of up to 100 A/m.

4.3.3 Specified measuring range of an operating class 2 current sensor
The specified measuring range of an operating class 2 current sensor is the range of
indicated values between stated lower and upper measurements for which the operating
uncertainty of reading is:
– less than 15 % for values less than or equal to 10 mA and is less than 10 % for values
greater than 10 mA for external low-frequency magnetic fields of up to 10 A/m;
and
– less than 20 % for values less than or equal to 10 mA and is less than 12,5 % for values
greater than 10 mA for external low-frequency magnetic fields of up to 30 A/m.
4.3.4 Specified measuring range of an operating class 3 current sensor
The specified measuring range of an operating class 3 instrument is the range of indicated
values between stated lower and upper measurements for which the operating uncertainty of
reading is:
– less than 15 % for values less than or equal to 10 mA and is less than 10 % for values
greater than 10 mA for external low-frequency magnetic fields of up to 10 A/m.
Table 1 – Relation between external magnetic field and operating class
External magnetic field strength 10 A/m 30 A/m 100 A/m
Operating uncertainty of reading  ≤ 10 mA 15 % 20 % 30 %
Operating uncertainty of reading  > 10 mA 10 % 12,5 % 15 %
Operating class 1 current sensor
  
Operating class 2 current sensor -
 
Operating class 3 current sensor - -

– 12 – IEC 61557-13:2023 © IEC 2023

Key for Figure 1 and Figure 2:
x-axis: external magnetic field
y-axis: operating uncertainty
1 operating class 1
2 operating class 2
3 operating class 3
Figure 1 – Operating uncertainty in relation to operating class
and external magnetic field for measuring ranges
less than or equal to 10 mA
Figure 2 – Operating uncertainty in relation to operating classes
and external magnetic field and measuring ranges
greater than 10 mA
4.4 Reference conditions
The reference conditions in accordance with Table 2 apply.
Table 2 – Reference conditions
Reference Range of reference conditions Remark
Rated mains frequency ±1 %
Reference temperature 23 °C ± 2 °C
Reference position:
Clamp jaws 90° (±5°) to straight conductors See Figure 3
Conductors
6 mm cross section located within the center (±5°) of the
clamp jaws.
For the differential method, two straight conductors as
See Figure 3
close as possible are required.
Rated supply voltage or rated ±1 %
voltage of the battery
Fiducial value of load current ±5 % within 50 % and 100 % of the nominal range If applicable
according to the manufacturer's specifications
Low-frequency external 0 A/m
magnetic field
Leakage current Sinusoidal with a THD < 4 %
Touch current to earth 0 A
Current sensor insulated from earth or configuration
according to the manufacturer’s specification
Rated burden According to the manufacturer's specification If applicable

– 14 – IEC 61557-13:2023 © IEC 2023
The intrinsic uncertainty, A, is to be determined at least at the upper and lower limit of the
measuring range under reference conditions. Digitizing error, nonlinearity and traceability are
to be taken into account. The highest value is to be used for the calculation of the operating
uncertainty.
Figure 3 – Reference position for two straight conductors (differential method)

Figure 4 – Example of operating positions for differential method
4.5 Mechanical requirements
Current sensors in accordance with this document shall comply with the requirements of
IEC 61010-2-032:2019, Clause 8, Resistance to mechanical stresses.

4.6 Pollution degree
Current sensors in accordance with this document shall be designed at least for pollution
degree 2 in accordance with IEC 61010-1.
4.7 Measurement category
Current sensors in accordance with this document shall be designed at least for measurement
category III and minimum working voltage of 300 V in accordance with IEC 61010-2-032.
4.8 Electromagnetic compatibility (EMC)
In addition to the requirements of IEC 61557-1:2019, 4.6, the following applies.
Current sensors in accordance with this document shall comply with the immunity
requirements of IEC 61326-1:2020, Table 2. The emission requirements are Class B.
5 Marking and operating instructions
5.1 Marking
The requirements of IEC 61557-1:2019, 5.1 do not apply. The requirements of
IEC 61010‑2‑032:2019, 5.1.2, and the following requirements shall apply instead.
– Current sensors in accordance with this document shall be marked with a framed
pictogram which warns not to exceed the permissible limits of external low-frequency
magnetic fields related to the operating class. This pictogram shall be clearly visible in
normal position. The colour of the frame and pictogram shall contrast with the background.
Figure 5 shows an example of an applicable pictogram for operating class 1.

Figure 5 – Example for an applicable pictogram for operating class 1
using caution symbol ISO 7000-0434A:2004-01
– Current sensors in accordance with this document shall be marked with the specified
measuring range in accordance with 4.3.
In addition, maximum load current and rated range of frequency in accordance with 4.1
shall be marked.
– The intrinsic uncertainty shall not be marked on the current sensors.
The marking with the operating uncertainty is allowed.
5.2 Operating instructions
For current sensors, the requirements in accordance with IEC 61557-1:2019, 5.3 and
IEC 61010-2-032, 5.4.4 apply. The following additional information shall be provided, in
accordance with 5.1 of this document.
– Operating instructions shall include statements about optimized positioning of the current
sensors and evaluation of influences caused by low-frequency external magnetic fields
and caused by contamination of the jaws.
– Operating instructions shall include statements about rated burden, if applicable.
– Operating instructions shall include information about the relationship between load
current and measuring range for the differential method.

– 16 – IEC 61557-13:2023 © IEC 2023
– Operating instructions shall include information about the recommended recalibration
period.
– The pictogram in Figure 5 shall be listed under "Warning symbols" and shall be explained.
6 Tests
6.1 General
In addition to IEC 61557-1:2019, Clause 6, the calculation in accordance with 6.2 and
verifications in accordance with 6.3 and 6.4 shall be determined.
6.2 Operating uncertainty
The operating uncertainty for measuring functions shall be determined in accordance with
IEC 61557-1:2019, 4.2 taking into account applicable influencing quantities in accordance
with Table 3.
The operating uncertainty shall be calculated in accordance with Table 3 and in accordance
with the following.
– The variation due to position (Figure 4):
• The variation E due to position of the equipment shall be determined in position ±30°,
for any position of conductors within the clamp jaws.
cross section
• for the differential method two straight insulated conductors of 6 mm
with an insulation thickness of approximately 2 mm (H07 V-K or similar) as far apart as
possible within the clamp jaws are required (Figure 4);
The example of Figure 4 should be used to identify the worst-case position.
– The variation E due to the rated range of the supply voltage (or rated voltage range of
batteries if applicable);
– The variation E due to temperature shall be determined for all measuring functions under
the following conditions:
• at 0 °C to +35 °C or extended range specified by the manufacturer.
– The variation E due to the harmonics of the leakage current, see Table 2;
– The variation E due to external low-frequency magnetic field within the limits of 4.2 shall
be determined.
– The variation E due to the maximum load current, according to the manufacturer's
specification, shall be determined.
– The variation E due to touch current through circuit A1 in accordance with IEC 61010-1
between hand-held parts (covered with metal foil) and earth shall be determined. The
conductor shall be held at maximum common mode voltage and highest rated frequency.
– The variation E due to the rated range of frequency shall be determined.
– The variation E due to the repeatability of the measurement readings with at least
10 open and/or closed cycles (E ).
Table 3 – Calculation of the operating uncertainty
Intrinsic Reference conditions or specified Designation Requirements or Type of
uncertainty or operating range tests in accordance test
code
influence quantity with the relevant
parts of IEC 61557
Intrinsic uncertainty Reference conditions A IEC 61557-13:2023, R
4.4, 6.2
Position (of the Reference position ± 90° E IEC 61557-1:2019, T
1.1
equipment using 4.3
mechanical display)
Position (of the Reference position ± 30°, for any position E IEC 61557-13:2023,
T
1.2
conductor within the within the clamp jaws 6.2
clamp jaws)
E IEC 61557-1:2019,
Supply voltage At the limits stated by the manufacturer T
4.2, 4.3
Temperature 0 °C to +35 °C or extended range specified E IEC 61557-1:2019, T
by the manufacturer 4.2, 4.3
rd
System harmonics E IEC 61557-1:2019, T
5 % 3 harmonic of the nominal frequency
4.2
at 0°
th
6 % 5 harmonic of the nominal frequency
at 180°
th
5 % 7 harmonic of the nominal frequency
at 0°
External low- Operating class 1 at 100 A/m E IEC 61557-13:2023, T
frequency magnetic 6.2
30 A/m
field
10 A/m
Operating class 2 at 30 A/m
10 A/m
Operating class 3 at 10 A/m
Load current Nominal range of load current according to E IEC 61557-13:2023, T
manufacturer’s specification 6.2
Touch current Touch current through circuit A1 in E IEC 61557-13:2023, T
caused by common accordance with IEC 61010-1 between 6.2
mode voltage hand-held parts (covered with metal foil)
and earth. Conductor held at maximum
common mode voltage and highest rated
mains frequency.
Frequency Rated frequency range according to E IEC 61557-13:2023, T
manufacturer's specification 6.2
E
Repeatability Difference between the highest and lowest IEC 61557-13:2023, R
value of the intrinsic uncertainty 6.2
Operating IEC 61557-1:2019,
T
uncertainty (1) 4.2
BA± + E
∑
i
i
Key Percentage operating uncertainty (2)
A = intrinsic uncertainty
B
B% =±× 100 %

B = operating uncertainty
F
E = variations
i
F = fiducial value
R = routine test
T = type test
=
– 18 – IEC 61557-13:2023 © IEC 2023
6.3 Verification of the operating instructions
The existence of the information set out in 5.2 shall be verified (type test).
6.4 Verification of the marking
The existence of the marking according to 5.1 and the pictogram of Figure 5 shall be verified
(routine test).
Annex A
(informative)
Examples of measurement applications
Figure A.1 shows an example for measurement of protective conductor current with the direct
method.
Key for Figure A.1 and Figure A.2
E1 Equipment 1
En Equipment n
Figure A.1 – Example for measurement of protective conductor current – Direct method

– 20 – IEC 61557-13:2023 © IEC 2023
Figure A.2 shows an example for measurement of leakage current and including protective
conductor current with the differential method.

NOTE The examples in Figure A.1 and Figure A.2 are related to single-phase circuits. However, these examples
of measurements are also valid for circuits with three-phase and three-phase with neutral.
Figure A.2 – Example for measurement of leakage current including protective
conductor current – Differential method

Bibliography
IEC 60359, Electrical and electronic measurement equipment – Expression of the
performance
IEC 61326-2-2, Electrical equipment for measurement, control and laboratory use – EMC
requirements – Part 2-2: Particular requirements – Test configurations, operational conditions
and performance criteria for portable testing, measuring and monitoring equipment used in
low-voltage distribution systems

___________
– 22 – IEC 61557-13:2023 © IEC 2023
SOMMAIRE
AVANT-PROPOS . 24
INTRODUCTION . 26
1 Domaine d'application . 27
2 Références normatives . 27
3 Termes et définitions . 28
4 Exigences . 29
4.1 Exigences générales . 29
4.2 Classes de fonctionnement . 30
4.2.1 Généralités . 30
4.2.2 Classe de fonctionnement 1 . 30
4.2.3 Classe de fonctionnement 2 . 30
4.2.4 Classe de fonctionnement 3 . 30
4.3 Incertitude de fonctionnement de la plage de mesure spécifiée . 30
4.3.1 Généralités . 30
4.3.2 Plage de mesure spécifiée d'un capteur de courant de la classe de
fonctionnement 1 . 31
4.3.3 Plage de mesure spécifiée d'un capteur de courant de la classe de
fonctionnement 2 . 31
4.3.4 Plage de mesure spécifiée d'un capteur de courant de la classe de
fonctionnement 3 . 31
4.4 Conditions de référence . 33
4.5 Exigences mécaniques . 34
4.6 Degré de pollution . 35
4.7 Catégorie de mesure. 35
4.8 Compatibilité électromagnétique (CEM) .
...