IEC 61557-14:2023

IEC 61557-14 ®
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 14: Equipment for testing the safety of electrical equipment of machinery

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 14: Dispositifs de contrôle de la sécurité des appareils électriques sur
machines
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IEC 61557-14 ®
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 14: Equipment for testing the safety of electrical equipment of machinery

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 14: Dispositifs de contrôle de la sécurité des appareils électriques sur

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

– 2 – IEC 61557-14:2023 © IEC 2023
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Requirements . 7
4.1 General requirements . 7
4.2 Measuring functions . 7
4.2.1 Required measuring functions . 7
4.2.2 Measurement of resistance of protective bonding . 8
4.2.3 Measurement of fault loop impedance. 8
4.2.4 Measurement of insulation resistance . 8
4.2.5 Testing of the effectiveness of protective measures with RCD . 8
4.2.6 Voltage tests . 8
4.2.7 Measurement of residual voltage . 9
4.2.8 Measurement of leakage current . 9
4.3 Construction requirements for testing equipment . 9
4.3.1 Overload capability . 9
4.3.2 Sockets for service purposes . 10
4.3.3 Degree of protection . 10
4.3.4 Overvoltage and measurement categories . 10
4.4 Accessories . 10
5 Markings and operating instructions . 10
5.1 Markings . 10
5.2 Operating instructions . 11
6 Tests . 11
6.1 General . 11
6.2 Operating uncertainty . 11
6.3 Tests of measuring equipment according to measuring functions . 12
6.4 Test of construction requirements of test equipment . 12
Bibliography . 16

Table 1 – Test voltages . 8
Table 2 – Calculation of operating uncertainty . 13
Table 3 – Compliance tests of measuring equipment according to measuring function . 14
Table 4 – Test of construction requirements of test equipment . 15

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 14: Equipment for testing the safety of electrical
equipment of machinery
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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indispensable for the correct application of this publication.
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rights. IEC shall not be held responsible for identifying any or all such patent rights.
IEC 61557-14 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 2013. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) clarifying the introduction;
b) replaced "dielectric strength" by "voltage test";
c) requirement for maximum output current has been added in 4.2.6.1;
d) tripping time at electrical switching activated by two-hand operation has been added in
4.2.6.1;
– 4 – IEC 61557-14:2023 © IEC 2023
e) additional time limiting capability for the protection against electric shock for test persons
and bystanders in 4.2.6.2;
f) updated references for safety testing;
g) 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
85/875/FDIS 85/884/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.
INTRODUCTION
This document defines particular requirements for test and measurement equipment used to
determine the electrical safety of electrical equipment of machinery. The IEC 61010 series,
other parts of the IEC 61557 series and the IEC 60204 series do not cover all safety aspects of
equipment used for testing electrical equipment of machinery in accordance with the test
sequence of IEC 60204‑1.
This document provides additional measures to reduce the risk of electric shock for the test
persons and bystanders during voltage tests in the field. This document also defines
performance requirements for each test and measurement function to ensure reliable and
comparable results.
– 6 – IEC 61557-14:2023 © IEC 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 14: Equipment for testing the safety of electrical
equipment of machinery
1 Scope
This part of IEC 61557 defines special requirements for test and measurement equipment used
to determine the electrical safety of electrical equipment of machinery in accordance with
IEC 60204-1.
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 60204-1, Safety of machinery – Electrical equipment of machines – Part 1: General
requirements
IEC 60529, Degrees of protection provided by enclosures (IP Code)
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 61010-1:2010, Safety requirements for electrical equipment for measurement, control, and
laboratory use – Part 1: General requirements
IEC 61010-1:2010/AMD1:2016
IEC 61010-2-030, Safety requirements for electrical equipment for measurement, control, and
laboratory use – Part 2-030: Particular requirements for equipment having testing or measuring
circuits
IEC 61010-2-034, 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
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 61557-3, 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 3:
Loop impedance
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 61557-6, 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 6:
Effectiveness of residual current devices (RCD) in TT, TN and IT systems
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 61557-16, 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
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61557-1, IEC 61557‑2,
IEC 61557-3, IEC 61557-4, IEC 61557-6, IEC 61557-10 and IEC 61557-13 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
4 Requirements
4.1 General requirements
In addition to the requirements of IEC 61557-1:2019, Clause 4, the following requirements shall
apply.
4.2 Measuring functions
4.2.1 Required measuring functions
The measuring equipment shall be capable of measuring the following quantities as a minimum:
– resistance of protective bonding;
– fault loop impedance;
– effectiveness of residual current devices (RCDs);
– insulation resistance.
The following test or measuring functions may be combined with those listed above:
– voltage test;
– residual voltage;
– leakage current.
– 8 – IEC 61557-14:2023 © IEC 2023
The measuring equipment may include further measurement functions, provided that the
measuring functions listed above are not influenced.
NOTE A missing measuring function in combined equipment can be completed with a single instrument designed
in accordance with the IEC 61557 series.
4.2.2 Measurement of resistance of protective bonding
This part of the measuring equipment shall be in accordance with IEC 61557-4.
4.2.3 Measurement of fault loop impedance
This part of the measuring equipment shall be in accordance with IEC 61557-3.
In addition, the earth resistance may be measured in accordance with IEC 61557-5.
4.2.4 Measurement of insulation resistance
The measuring equipment shall be in accordance with IEC 61557-2.
4.2.5 Testing of the effectiveness of protective measures with RCD
This part of the measuring equipment shall be in accordance with IEC 61557-6.
4.2.6 Voltage tests
4.2.6.1 Requirements for voltage tests
If the equipment includes a voltage test, it shall generate a quasi-sinusoidal voltage at mains
frequency with values in accordance with Table 1.
NOTE 1 The test voltage is commonly derived from mains voltage.
NOTE 2 A waveform does not need to be a perfect sine curve, but be close enough to be considered sinusoidal, for
all practical purposes.
Table 1 – Test voltages
Nominal voltage U of equipment under test (EUT) Test voltage
n
≤ 500 V 1 000 V
> 500 V 2 × U
n
The rated test current shall be 100 mA AC with a tolerance of 0 % to +2 %. The minimum
prospective short circuit current shall be 200 mA. The maximum output current measured via a
resistor with a maximum value of 2 kΩ shall not exceed 250 mA.
If the test equipment has a display to indicate the actual test voltage, the maximum operating
uncertainty shall be ±5 %.
The amplitude of the test voltage output shall be regulated such that any variation is within 10 %
and +30 % of the rated test voltage within 500 ms after changing the load from an unloaded
condition (open circuit) to a loaded condition (100 mA) and vice versa. The maximum voltage
overshoot shall be less than 200 % of the rated test voltage.
The touch current measured at each output terminal via the measuring circuit in accordance
with IEC 61010-1:2010, Figure A.1, to earth shall not exceed 3,5 mA AC. The EUT shall not be
connected.
The voltage test duration is defined in IEC 60204-1.
The test equipment shall have provisions against unintended energizing of the output. Such
methods of protection shall include one of the examples in accordance with
IEC 61010‑2‑034:2017, 6.9.101, a), b) or c) and in addition two-hand operation method d).
Two-hand operation can be provided by electronic or mechanical means.
In the case of electrical switching activated by two-hand operation, the tripping time shall not
exceed 70 ms.
4.2.6.2 Additional time limiting capability
If the equipment provides the possibility to set a tripping current of 30 mA for the output current,
then the setting shall be clearly indicated and the maximum tripping time shall be 250 ms.
NOTE The additional time limiting capability will increase the protection against electric shock for bystanders in the
case of large machinery where the testing person does not have visibility of the whole test area.
Test equipment shall have provisions for discharging the EUT in accordance with
IEC 61010‑2‑034.
Test equipment shall include protective measures to avoid automatic reenergizing of the output
in accordance with IEC 61010-2-034.
4.2.7 Measurement of residual voltage
If the equipment can measure the residual voltage, the operating uncertainty to measure this
voltage shall be within 0 % to +15 % of the 60 V limit, and the operating uncertainty to set the
measuring time limit shall be within 0 % and −15 % of the 1 s limit or 5 s limit.
Evaluated voltages in linear systems shall be calculated as if they were measured during the
maximum amplitude of the interrupted voltage. If the manufacturer specifies the test equipment
to be used in non-linear systems, the measuring method shall be explained in the operating
instructions.
The input impedance of the voltage measurement circuit shall be at least 20 MΩ.
4.2.8 Measurement of leakage current
If the measuring equipment can measure leakage currents, this part of the measuring equipment
and attached current sensors shall be in accordance with the requirements of IEC 61557-13
(for current clamps and sensors) or IEC 61557-16 (for electrical equipment or medical electrical
equipment).
4.3 Construction requirements for testing equipment
4.3.1 Overload capability
The overload capability of combined measuring equipment shall be in accordance with
IEC 61557-10. In addition, no hazard shall arise for the user when the maximum value of the
output voltage is accidentally applied to the energized external distribution system.
To check this requirement, the output voltage is applied for one minute to each combination of
the nominal line-to-neutral mains voltage specified for the equipment.
Protective devices may be activated. The loop impedance of the main circuit used to perform
the overload test shall be equal to or lower than 2 Ω.

– 10 – IEC 61557-14:2023 © IEC 2023
4.3.2 Sockets for service purposes
Sockets for the connection of further external equipment shall be clearly marked. Protection
against overcurrent and short-circuits for the mains circuits connected to these sockets shall
be provided by:
a) double insulation between active conductors, and between each active conductor and the
protective conductor, or
b) overcurrent protective devices.
In case of solution a), a clear warning shall be given in the documentation not to connect to
unprotected outlets.
The inner wiring of the service socket shall be designed according to the maximum nominal
current, but at least for 16 A.
4.3.3 Degree of protection
The degree of protection for the enclosure, except service-sockets and terminals, shall be at
least IP40 in accordance with IEC 60529.
4.3.4 Overvoltage and measurement categories
4.3.4.1 Overvoltage category
The supply circuit of the testing equipment shall be rated at least for overvoltage category II, in
accordance with IEC 61010-2-034.
4.3.4.2 Measurement category
With the exception of the measuring circuit for resistance of protective bonding, insulation
resistance and the voltage test circuit, all other measuring circuits of the test equipment shall
be rated at least for CAT III in accordance with IEC 61010-2-034.
The measuring circuit for resistance of protective bonding and insulation resistance shall be
rated at least CAT II. The voltage test circuit may be classified as secondary circuit in
accordance with IEC 61010-2-034 if the circuit is separated from the mains circuit by a
transformer.
4.4 Accessories
Specified accessories shall comply with the requirements of IEC 61010-031.
5 Markings and operating instructions
5.1 Markings
In addition to the markings in accordance with IEC 61557-1:2019, 5.1 and 5.2, as well as
markings in accordance with other relevant parts of the IEC 61557 series, IEC 61010-1,
IEC 61010-2-030, and IEC 61010-2-034, the measuring equipment shall have the following
information clearly visible:
– service-socket, if applicable, with maximum rated current;
– test and measurement terminals;
– measuring function;
– instructions for connection.

5.2 Operating instructions
In addition to the operating instructions in accordance with IEC 61557-1:2019, 5.3, IEC 61010-1,
IEC 61010-2-030, and IEC 61010-2-034, the following information shall be provided in the
operating instructions for the measuring equipment:
– for measuring equipment with service-socket: if applicable, the information that the
installation of the distribution system shall provide protection against overcurrent,
short-circuits and electric shock in accordance with 4.3.3;
– operating uncertainty, intrinsic uncertainty, influencing quantities and their effects;
– for testing equipment capable of voltage tests in accordance with 4.2.6, additional warnings
to mark and to separate the surroundings of machinery during the test;
– recommendations about intervals for recalibration.
6 Tests
6.1 General
In addition to IEC 61557-1:2019, Clause 6, calculation in accordance with 6.2 and verifications
in accordance with 6.3 and 6.4 shall be determined.
6.2 Operating uncertainty
The maximum percentage 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 2.
The intrinsic uncertainty A shall be determined for each measured parameter under the following
reference conditions (routine test):
– nominal system voltage;
– nominal system frequency;
– reference temperature 23 °C ± 2 °C;
– reference position according to the manufacturer's specification;
– nominal supply voltage or battery voltage;
– no low-frequency external magnetic field;
– difference between phase angle of loading equipment and loop impedance under test ≤ 5°
in case of measurement of loop impedance.
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.
The operating uncertainty shall be calculated in accordance with Table 2.
– The variation due to position:
due to position of the equipment shall be determined in positions +90°
• the variation E
1.1
and −90° from the reference position for all measuring functions, if applicable.
• The variation E due to position of the conductor within the clamp jaws shall be
1.2
determined in positions +30° and −30°, if applicable.
– The variation E due to supply voltage shall be determined for all measuring functions under
the following conditions:
• for measuring equipment with mains supply at −15 % and +10 % of the nominal voltage;

– 12 – IEC 61557-14:2023 © IEC 2023
• for measuring equipment with battery supply at the limits defined under
IEC 61557‑1:2019, 4.4.
– The variation E due to temperature shall be determined for all measuring functions under
the following conditions:
• at 0 °C and at +35 °C after the equipment has reached steady state conditions.
– The variation E or E due to the system phase angle shall be determined at 18° or, if
6.1 6.2
applicable, at 30° for the measurement of loop impedance.
– The variation E due to the system frequency for measurement shall be determined at 99 %
and 101 % for measurement of the loop impedance.
– The variation E due to the system voltage shall be determined at 85 % and 110 % of the
system voltage for measurement of the loop impedance.
– The variation E due to the harmonics shall be determined for the measurement of the loop
impedance at:
rd
• 5 % of 3 harmonic at 0° phase angle;
th
• 6 % of 5 harmonic at 180° phase angle;
th
• 5 % of 7 harmonic at 0° phase angle;
• Percentage of harmonics shall be determined from the fundamental of the nominal
system voltage.
– The variation E due to DC quantities for the measurement of loop impedance shall be
determined at 0,5 % of the nominal system voltage in both polarities.
– The variation E due to external low-frequency magnetic field of a leakage current clamp
shall be determined, if applicable.
– The variation E due to load current of a leakage current clamp shall be determined, if
applicable.
– The variation E due to touch current caused by common mode voltage of a leakage current
clamp shall be determined, if applicable.
– The variation E due to frequency of the measured current shall be determined, if
applicable.
– The variation E due to repeated clamping of a leakage current clamp shall be determined,
if applicable.
6.3 Tests of measuring equipment according to measuring functions
Testing of measuring equipment according to the measuring functions shall be performed in
accordance with Table 3.
6.4 Test of construction requirements of test equipment
Requirements of Clause 4 shall be tested and verified.
Testing of construction requirements of test equipment shall be performed in accordance with
Table 4.
Table 2 – Calculation of operating uncertainty
Intrinsic uncertainty or Reference conditions or Designation Requirements Type of
influence quantity specified operating range code or test in accordance test
with the relevant parts
of series IEC 61557
Intrinsic uncertainty Reference conditions A IEC 61557-14:2023, 6.2 R
Position (of equipment Reference position ±90° E IEC 61557-1:2019, 4.2 T
1.1
using mechanical
displays)
Position (of the Reference position ±30° for E 1 T
1.2 IEC 61557-13:— , 6.2
conductor within the any position within the clamp
clamp jaws) jaws
Supply voltage 85 % and 110 % E IEC 61557-1:2019, 4.3 R
E
Battery supply As specified IEC 61557-1:2019, 4.4 R
Temperature 0 °C to +35 °C or extended E IEC 61557-1:2019, T
range specified by the 6.2.3
manufacturer
Phase angle At a phase angle 0° to 18° E IEC 61557-3:2019, 6.2 T
approximately
a
System phase angle At a system phase angle 0° to IEC 61557-14:2023, 6.2 T
E
6.1
18° at the bottom of the
measurement range
a
System phase angle At a system phase angle 0° to IEC 61557-14:2023, 6.2 T
E
6.2
30° at the bottom of the
measurement range
System frequency Between 99 % and 101 % of E IEC 61557-14:2023, 6.2 T
the nominal frequency
System voltage Between 85 % to 110 % of the E IEC 61557-14:2023, 6.2 T
nominal voltage
rd
System harmonics E IEC 61557-3:2019, 6.2 T
5 % of the 3 harmonic at 0°
phase angle
th
6 % of the 5 harmonic at
180° phase angle
th
5 % of the 7 harmonic at 0°
phase angle
(percentage of the
fundamental of the nominal
voltage of the distribution
system)
b
DC quantity Add additional DC quantities IEC 61557-3:2019, 6.2 T
E
of 0,5 % of the nominal
voltage of distribution system
in both polarities.
It is recommended that
manufacturers include E
into the calculation of
operating uncertainty
according to this Table 2.
External low-frequency Operating class 1 at 100 A/m E IEC 61557-13:—, 6.2 T
magnetic field  30 A/m
10 A/m
Operating class 2 at 30 A/m
10 A/m
Operating class 3 at 10 A/m
___________
Under preparation. Stage at the time of publication: IEC FDIS 61557-13:2023.

– 14 – IEC 61557-14:2023 © IEC 2023
Intrinsic uncertainty or Reference conditions or Designation Requirements Type of
influence quantity specified operating range code or test in accordance test
with the relevant parts
of series IEC 61557
Load current Nominal range of load current E IEC 61557-13:—, 6.2 T
according to manufacturer's
specification
Touch current caused Touch current through circuit E IEC 61557-13:—, 6.2 T
by common mode according to Figure A.1 of
voltage IEC 61010-1:2010 between
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 E IEC 61557-13:—, 6.2 T
according to manufacturer's
specification
Repeatability Difference between the E IEC 61557-13:—, 6.2 R
highest and lowest value of
the intrinsic uncertainty
Operating uncertainty IEC 61557-1:2019, 4.2 T
(1)
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
a
Use E or E as applicable.
6.1 6.2
b
Influence quantity E takes into account possible voltage drops caused by DC leakage currents in accordance
with IEC 61800-5-2 on the PE or PEN- conductor.

Table 3 – Compliance tests of measuring equipment according to measuring function
Measuring function Compliance verification Requirements in Type test Routine
accordance with test
subclause
Resistance of protective bonding 4.2.2 X
Fault loop impedance 4.2.3 X X
Insulation resistance 4.2.4 X X
Testing of the effectiveness of 4.2.5 X X
protective measure with RCD
Voltage test If applicable, compliance 4.2.6.1 X
with requirements shall
be verified by
– Uncertainty of setting 4.2.6.1 X
– Additional protective 4.2, 6.2 X
measures
Residual voltage If applicable 4.2.7 X X
Leakage current If applicable 4.2.8 X X

=
Table 4 – Test of construction requirements of test equipment
Test of Compliance with Type test Routine test
requirements in
accordance with
subclause
Overload capability of combined equipment 4.3.1 X
Sockets for service purposes 4.3.2 X
Degree of protection 4.3.3 X
Overvoltage and measurement category 4.3.4 X
Accessories 4.4 X
Markings 5.1 X
Operating instructions 5.2 X
– 16 – IEC 61557-14:2023 © IEC 2023
Bibliography
IEC 60479-1, Effects of current on human beings and livestock – Part 1: General aspects
IEC 61000-4-8, Electromagnetic compatibility (EMC) – Part 4-8: Testing and measurement
techniques – Power frequency magnetic field immunity test
IEC 61800-5-2, Adjustable speed electrical power drive systems – Part 5-2: Safety
requirements – Functional
___________
– 18 – IEC 61557-14:2023 © IEC 2023
SOMMAIRE
AVANT-PROPOS . 19
INTRODUCTION . 21
1 Domaine d’application . 22
2 Références normatives . 22
3 Termes et définitions . 23
4 Exigences . 23
4.1 Exigences générales . 23
4.2 Fonctions de mesure. 24
4.2.1 Fonctions de mesure exigées . 24
4.2.2 Mesure de la résistance de la liaison de protection . 24
4.2.3 Mesure de l’impédance de boucle de défaut . 24
4.2.4 Mesure de la résistance d’isolement . 24
4.2.5 Essai de l’efficacité des mesures de protection avec les dispositifs à
courant différentiel résiduel (DDR) . 24
4.2.6 Essais de tension . 24
4.2.7 Mesure de la tension résiduelle . 26
4.2.8 Mesure du courant de fuite . 26
4.3 Exigences de construction pour le dispositif de contrôle . 26
4.3.1 Capacité de surcharge . 26
4.3.2 Prises de courant pour des besoins de service . 26
4.3.3 Degré de protection . 26
4.3.4 Catégories de surtension et de mesure . 27
4.4 Accessoires . 27
5 Marquages et instructions de fonctionnement . 27
5.1 Marquages . 27
5.2 Instructions de fonctionnement . 27
6 Essais . 27
6.1 Généralités . 27
6.2 Incertitude de fonctionnement . 28
6.3 Essais des dispositifs de mesure selon les fonctions de mesure . 29
6.4 Essai des exigences de construction du dispositif de contrôle . 29
Bibliographie . 33

Tableau 1 – Tensions d’essai. 25
Tableau 2 – Calcul de l’incertitude de fonctionnement . 29
Tab
...