EN IEC 61557-3:2022

SLOVENSKI STANDARD
01-oktober-2022
Nadomešča:
SIST EN 61557-3:2007
Električna varnost v nizkonapetostnih razdelilnih sistemih za izmenične napetosti
do 1 000 V in enosmerne napetosti do 1 500 V - Oprema za preskušanje, merjenje
ali nadzorovanje zaščitnih ukrepov - 3. del: Impedanca zanke (IEC 61557-3:2019)
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 3: Loop
impedance (IEC 61557-3:2019)
Elektrische Sicherheit in Niederspannungsnetzen bis AC 1 000 V und DC 1 500 V -
Geräte zum Prüfen, Messen oder Überwachen von Schutzmaßnahmen - Teil 3:
Schleifenwiderstand (IEC 61557-3:2019)
Sécurité électrique dans les réseaux de distribution basse tension de 1 000 V c.a. et 1
500 V c.c. - Dispositifs de contrôle, de mesure ou de surveillance de mesures de
protection - Partie 3: Impédance de boucle (IEC 61557-3:2019)
Ta slovenski standard je istoveten z: EN IEC 61557-3:2022
ICS:
17.220.20 Merjenje električnih in Measurement of electrical
magnetnih veličin and magnetic quantities
29.080.01 Električna izolacija na Electrical insulation in
splošno general
29.240.01 Omrežja za prenos in Power transmission and
distribucijo električne energije distribution networks in
na splošno general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 61557-3

NORME EUROPÉENNE
EUROPÄISCHE NORM May 2022
ICS 17.220.20; 29.080.01; 29.240.01 Supersedes EN 61557-3:2007
English Version
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 61557-3:2019)
Sécurité électrique dans les réseaux de distribution basse Elektrische Sicherheit in Niederspannungsnetzen bis AC
tension au plus égale à 1 000 V c.a. et 1 500 V c.c. - 1 000 V und DC 1 500 V - Geräte zum Prüfen, Messen oder
Dispositifs de contrôle, de mesure ou de surveillance de Überwachen von Schutzmaßnahmen - Teil 3:
mesures de protection - Partie 3: Impédance de boucle Schleifenwiderstand
(IEC 61557-3:2019) (IEC 61557-3:2019)
This European Standard was approved by CENELEC on 2022-04-06. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 61557-3:2022 E

European foreword
The text of document 85/687/FDIS, future edition 3 of IEC 61557-3, prepared by IEC/TC 85
"Measuring equipment for electrical and electromagnetic quantities" was submitted to the IEC-
CENELEC parallel vote and approved by CENELEC as EN IEC 61557-3:2022.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2023-01-06
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2025-04-06
document have to be withdrawn
This document supersedes EN 61557-3:2007 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a Standardization Request given to CENELEC by the
European Commission and the European Free Trade Association.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 61557-3:2019 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following note has to be added for the standard indicated:
IEC 61800-5-2 NOTE Harmonized as EN 61800-5-2
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 61010-1 2010 Safety requirements for electrical EN 61010-1 2010
equipment for measurement, control, and
laboratory use - Part 1: General
requirements
+ A1 (mod) 2016 + A1 2019
IEC 61010-2-030 2017 Safety requirements for electrical EN IEC 61010-2-030 2021
equipment for measurement, control, and
laboratory use - Part 2-030: Particular
requirements for equipment having
testing or measuring circuits
- - + A11 2021
IEC 61557-1 2019 Electrical safety in low voltage distribution EN IEC 61557-1 2021
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 61557-3 ®
Edition 3.0 2019-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electrical safety in low voltage distribution systems up to 1 000 V a.c. and

1 500 V d.c. – Equipment for testing, measuring or monitoring of protective

measures –
Part 3: Loop impedance
Sécurité électrique dans les réseaux de distribution basse tension au plus égale

à 1 000 V c.a. et 1 500 V c.c. – Dispositifs de contrôle, de mesure ou de

surveillance de mesures de protection –

Partie 3: Impédance de boucle
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.220.20; 29.080.01; 29.240.01 ISBN 978-2-8322-7156-8

– 2 – IEC 61557-3:2019 © IEC 2019
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions. 5
4 Requirements . 6
4.1 General . 6
4.2 Measurement of loop impedance . 6
4.3 External resistance . 6
4.4 Fault voltage exceeding U . 7
L
4.5 Overvoltage . 7
5 Marking and operating instructions . 7
5.1 Marking . 7
5.2 Operating instructions . 7
6 Tests . 8
6.1 General . 8
6.2 Operating uncertainty . 8
6.3 External resistance . 10
6.4 Fault voltage . 10
6.5 Overvoltage . 10
Bibliography . 11

Table 1 – Calculation of operating uncertainty . 9

IEC 61557-3:2019 © IEC 2019 – 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 3: Loop impedance
FOREWORD
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