IEC 61557-14:2023

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

IEC 61557-14:2023 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.
This International Standard is to be used in conjunction with IEC 61557-1:2019.
IEC 61557-14:2023 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;
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.

Sécurité électrique dans les réseaux de distribution basse tension jusqu’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

L'IEC 61557-14:2023 définit les exigences particulières applicables aux dispositifs de contrôle et de mesure destinés à déterminer la sécurité électrique des appareils électriques sur machines conformément à l’IEC 60204-1.
L'IEC 61557-14:2023 annule et remplace la première édition parue en 2013. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l’édition précédente:
a) clarification de l’introduction;
b) remplacement de "rigidité diélectrique" par "essai de tension";
c) ajout de l’exigence de courant de sortie maximal en 4.2.6.1;
d) ajout du temps de déclenchement lors de la commutation électrique activée par une opération à deux mains en 4.2.6.1;
e) ajout d’une capacité de limitation de temps supplémentaire pour la protection contre les chocs électriques pour les personnes soumises à essai et les personnes présentes en 4.2.6.2;
f) mise à jour des références pour les essais de sécurité;
g) 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
• 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: 18-Aug-2023
• Completion Date: 25-Aug-2023

Relations

• Revises: IEC 61557-14:2013 - 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 14: Equipment for testing the safety of electrical equipment for machinery
• Effective Date: 05-Sep-2023

Standards Content (Sample)

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
IEC 61557-14:2023-08(en-fr)

---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
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




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 61557-14:2023 © 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

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IEC 61557-14:2023 © IEC 2023 – 3 –
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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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;

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– 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.

---------------------- Page: 6 ----------------------
IEC 61557-14:2023 © IEC 2023 – 5 –
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.

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– 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

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IEC 61557-14:2023 © IEC 2023 – 7 –
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.

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– 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.

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IEC 61557-14:2023 © IEC 2023 – 9 –
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.

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– 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 Markin
...