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SIST EN 61557-11:2009
01-junij-2009
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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 11:
Effectiveness of residual current monitors (RCMs) type A and type B in TT, TN and IT
systems
Elektrische Sicherheit in Niederspannungsnetzen bis AC 1 000 V und DC 1 500 V -
Geräte zum Prüfen, Messen oder Überwachen von Schutzmaßnahmen -- Teil 11:
Wirksamkeit von Differenzstrom-Überwachungsgeräten (RCMs) Typ A und Typ B in TT-,
TN- und IT-Systemen
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 11: Efficacité des contrôleurs d'isolement à courant différentiel
résiduel (RCM) de type A et de type B dans les réseaux TT, TN et IT
Ta slovenski standard je istoveten z: EN 61557-11:2009
ICS:
17.220.20 0HUMHQMHHOHNWULþQLKLQ Measurement of electrical
PDJQHWQLKYHOLþLQ and magnetic quantities
29.240.01 2PUHåMD]DSUHQRVLQ Power transmission and
GLVWULEXFLMRHOHNWULþQHHQHUJLMH distribution networks in
QDVSORãQR general
SIST EN 61557-11:2009 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 61557-11:2009
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SIST EN 61557-11:2009
EUROPEAN STANDARD
EN 61557-11
NORME EUROPÉENNE
March 2009
EUROPÄISCHE NORM
ICS 17.220.20; 29.080.01; 29.240.01
English version
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 11: Effectiveness of residual current monitors (RCMs)
type A and type B in TT, TN and IT systems
(IEC 61557-11:2009)
Sécurité électrique dans les réseaux Elektrische Sicherheit
de distribution basse tension in Niederspannungsnetzen
de 1 000 V c.a. et 1 500 V c.c. - bis AC 1 000 V und DC 1 500 V -
Dispositifs de contrôle, de mesure ou Geräte zum Prüfen, Messen oder
de surveillance de mesures de protection - Überwachen von Schutzmaßnahmen -
Partie 11: Efficacité des contrôleurs Teil 11: Wirksamkeit von Differenzstrom-
d'isolement à courant différentiel résiduel Überwachungsgeräten (RCMs) Typ A
(RCM) de type A et de type B und Typ B in TT-, TN- und IT-Systemen
dans les réseaux TT, TN et IT (IEC 61557-11:2009)
(CEI 61557-11:2009)
This European Standard was approved by CENELEC on 2009-02-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: avenue Marnix 17, B - 1000 Brussels
© 2009 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61557-11:2009 E
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SIST EN 61557-11:2009
EN 61557-11:2009 - 2 -
Foreword
The text of document 85/338/FDIS, future edition 1 of IEC 61557-11, prepared by IEC TC 85, Measuring
equipment for electrical and electromagnetic quantities, was submitted to the IEC-CENELEC parallel vote
and was approved by CENELEC as EN 61557-11 on 2009-02-01.
This standard is to be used in conjunction with EN 61557-1:2007.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2009-11-01
– latest date by which the national standards conflicting
(dow) 2012-02-01
with the EN have to be withdrawn
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 61557-11:2009 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 60364-4-41 NOTE Harmonized as HD 60364-4-41:2007 (modified).
IEC 60364-5-53 NOTE Clause 534 (in IEC/A1:2002) harmonized as HD 60364-5-534:2008 (modified).
IEC 60364-6 NOTE Harmonized as HD 60364-6:2007 (modified).
IEC 60947-2 NOTE Harmonized as EN 60947-2:2006 (not modified).
IEC 61008-1 NOTE Harmonized as EN 61008-1:2004 (modified).
__________
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SIST EN 61557-11:2009
- 3 - EN 61557-11:2009
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following referenced documents are indispensable for the application 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 When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year
IEC/TR 60755 2008 General requirements for residual current - -
operated protective devices
IEC 61010-1 2001 Safety requirements for electrical EN 61010-1 2001
equipment for measurement, control, and + corr. June 2002
laboratory use -
Part 1: General requirements
1) 2)
IEC 61326-2-2 - Electrical equipment for measurement, EN 61326-2-2 2006
control and laboratory use -
EMC requirements -
Part 2-2: Particular requirements - Test
configurations, operational conditions and
performance criteria for portable test,
measuring and monitoring equipment used in
low-voltage distribution systems
1) 2)
IEC 61557-1 - Electrical safety in low voltage distribution EN 61557-1 2007
systems up to 1 000 V a.c. and 1 500 V d.c. -
Equipment for testing, measuring or
monitoring of protective measures -
Part 1: General requirements
1) 2)
IEC 61557-6 - Electrical safety in low voltage distribution EN 61557-6 2007
systems up to 1 000 V a.c. and 1 500 V d.c. -
Equipment for testing, measuring or
monitoring of protective measures -
Part 6: Effectiveness of residual current
devices (RCD) in TT, TN and IT systems
IEC 62020 1998 Electrical accessories - Residual current EN 62020 1998
monitors for household and similar uses
(RCMs)
1)
Undated reference.
2)
Valid edition at date of issue.
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SIST EN 61557-11:2009
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SIST EN 61557-11:2009
IEC 61557-11
Edition 1.0 2009-01
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 11: Effectiveness of residual current monitors (RCMs) type A and type B in
TT, TN and IT systems
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 11: Efficacité des contrôleurs d'isolement à courant différentiel résiduel
(RCM) de type A et de type B dans les réseaux TT, TN et IT
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
S
CODE PRIX
ICS 17.220.20; 29.080.01; 29.240.01 ISBN 2-8318-1023-8
Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
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SIST EN 61557-11:2009
– 2 – 61557-11 © IEC:2009
CONTENTS
FOREWORD.3
1 Scope.5
2 Normative references.5
3 Terms and definitions .5
4 Requirements .7
4.1 Operating test.7
4.2 Non-operating test .8
4.3 Test of actuating time .8
4.4 Operating conditions.8
4.5 Prevention of danger by fault voltages exceeding 50 V a.c. or 120 V d.c. in the
monitored system during measurement.8
4.6 Prevention of danger caused by overvoltages when the system is connected.9
4.7 Electromagnetic compatibility (EMC) .9
5 Marking and operating instructions.9
5.1 Markings .9
5.2 Operating instructions.9
5.2.1 Information .9
5.2.2 Warnings .9
6 Tests .10
6.1 General .10
6.2 Operating uncertainty.10
Annex A (informative) Differences between RCMs and RCDs .14
Annex B (informative) Safety aspects, test methods and applications.18
Bibliography .20
Figure 1 – Maximum steepness of stepwise rising smooth direct test current (I ) .12
T
Figure 2 – Maximum increase of linearly increasing smooth direct test current (I ).12
T
Figure 3 – Example for linearly increasing smooth direct test current (I ): I = 30 mA .13
T ∆N
Figure A.1 – Typical installation with a combination of RCDs and RCMs .17
Table 1 – Calculation of operating uncertainty .11
Table A.1 – Normative reference and definition of function of RCM and RCD .14
Table A.2 – Requirements for testing RCMs according to product standard
IEC 62020:1998 .15
Table A.3 – Main technical differences between RCMs and RCDs .16
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SIST EN 61557-11:2009
61557-11 © IEC:2009 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
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 11: Effectiveness of residual current monitors (RCMs)
type A and type B in TT, TN and IT systems
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 in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61557-11 has been prepared by IEC technical committee 85:
Measuring equipment for electrical and electromagnetic quantities.
The text of this standard is based on the following documents:
FDIS Report on voting
85/338/FDIS 85/343/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
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SIST EN 61557-11:2009
– 4 – 61557-11 © IEC:2009
This part is to be used in conjunction with IEC 61557-1:2007, Part 1: General requirements.
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 a.c. and 1 500 V d.c. – 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 publication will remain unchanged until the
maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition; or
• amended.
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SIST EN 61557-11:2009
61557-11 © IEC:2009 – 5 –
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 11: Effectiveness of residual current monitors (RCMs)
type A and type B in TT, TN and IT systems
1 Scope
This part of IEC 61557 specifies the requirements for testing equipment applied to the testing
of the effectiveness of residual current monitors (RCMs) of type A and type B, which are
already installed in distribution systems.
This test equipment can be used in any kind of network like a TN, TT or IT system. The test
equipment may also be used for testing directionally discriminating RCMs in IT-Systems.
2 Normative references
The following referenced documents are indispensable for the application 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/TR 60755:2008, General requirements for residual current operated protective devices
IEC 61010-1:2001, Safety requirements for electrical equipment for measurement, control, and
laboratory use – Part 1: General requirements
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 test, measuring and monitoring equipment used in low-
voltage distribution systems
IEC 61557-1, 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 1: General
requirements
IEC 61557-6, 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 6:
Effectiveness of residual current devices (RCD) in TT, TN and IT systems
IEC 62020:1998, Electrical accessories – Residual current monitors for household and similar
uses (RCMs)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61557-1, IEC 61557-
6 and the following apply.
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SIST EN 61557-11:2009
– 6 – 61557-11 © IEC:2009
3.1
residual current monitor (RCM)
device or association of devices which monitors the residual current in an electrical installation
and which activates an alarm when the residual current exceeds the operating value of the
device
[IEC 62020, definition 3.3.1]
3.2
earth fault current
I
e
current flowing to earth due to an insulation fault
[IEC 62020, definition 3.1.1]
3.3
test current
I
T
test current superimposed by the test equipment for testing the effectiveness of the RCM
3.4
residual current
I
∆
vector sum of the instantaneous values of the current flowing in the main circuit of the RCM
(expressed as r.m.s. value)
[IEC 62020, definition 3.2.3]
3.5
rated residual operating current
I
∆N
value of residual current assigned by the manufacturer which causes the RCM to operate under
specified conditions
[IEC 62020, definitions 3.2.4 and 3.4.1 combined]
3.6
residual operating current
I
∆o
value of residual current which causes the RCM to operate under specified conditions
[IEC 62020, definition 3.2.4]
3.7
residual non-operating current
I
∆no
value of residual current at which and below which the RCM does not operate under specified
conditions
[IEC 62020, definition 3.2.5]
3.8
actuating time
t
a
time taken for a RCM to change from the non-alarm state to the alarm state in response to the
sudden appearance of a residual current which exceeds the preset level
[IEC 62020, definition 3.3.12]
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SIST EN 61557-11:2009
61557-11 © IEC:2009 – 7 –
3.9
residual current monitor (RCM) type A
RCM for which monitoring is ensured for residual sinusoidal alternating currents and residual
pulsating direct currents, whether suddenly applied or slowly rising
[IEC 62020, definition 3.3.8, modified]
3.10
residual current monitor (RCM) type B
RCM for which monitoring is ensured for residual sinusoidal alternating currents, with residual
pulsating direct currents and smooth residual direct currents independent of polarity, whether
suddenly applied or slowly rising
[IEC/TR 60755, definition 5.2.9.3, modified]
4 Requirements
The following requirements as well as those given in IEC 61557-1 shall apply.
4.1 Operating test
The testing equipment shall be capable of verifying that the residual operating current of a
RCM type A tested with an a.c. test current is lower or equal to the value of the rated residual
operating current.
Testing of RCMs type A shall be conducted with a suddenly applied calibrated a.c. current at
zero crossing.
The tests shall be carried out with a sinusoidal, or mains-derived quasi sinusoidal, test current.
If the test equipment is capable of producing half-wave test currents, testing of residual current
monitors (RCMs) type A may be carried out alternatively with half-wave test currents and/or a.c.
current with superimposed ±6 mA d.c. according to IEC 62020.
In case of pulsed d.c. current, the test equipment shall be capable of testing in both polarities.
When testing RCMs of type B with a d.c. test current, it shall be verified that the residual
operating current is lower or equal to 2 times the value of the rated residual operating current.
Testing of RCMs type B shall be conducted separately with a suddenly applied, calibrated a.c.
current and a continuously rising smooth direct current.
The steepness of the continuous rate of rising shall not be higher than 2 × I / 5 s.
∆N
If the continuous rate of rising is simulated by a stepwise or linearly increasing test current, the
increase shall not be higher than 2 × I / 30 (see Figures 1 to 3).
∆N
In both cases the starting current shall be below 0,2 × I .
∆N
The operating uncertainty of the increasing test current I shall not exceed ±10 % of the rated
T
residual operating current I
.
∆N
The operating uncertainty of the calibrated test current I shall not exceed 0 % to +10 %.
T
The test period shall be adapted to the set actuating time of the RCM and it shall be possible to
extend the test period up to 10 s.
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SIST EN 61557-11:2009
– 8 – 61557-11 © IEC:2009
4.2 Non-operating test
When a test at 50 % or less of the rated residual operating current to test the reliability of the
RCM is included, the minimum test period shall be 10 s. The alarm shall not be activated.
When a non-operating test at 50 % or less of the rated residual operating current is included,
the operating uncertainty of the calibrated test current shall not exceed 0 % to –10 % of the
specified non-operating test current.
NOTE Existing leakage currents downstream can influence the verification.
4.3 Test of actuating time
If the set actuating time of the RCM is being tested with the test equipment, the setting of the
test period on the test device shall have a resolution of minimum 0,5 s ranging up to 10 s. The
setting uncertainty shall not exceed 0 % to –10 % of the set value. The test shall solely be
performed with calibrated a.c. test current.
Other methods for the acquisition of the actuating time via optical recognition or interfacing are
permissible.
NOTE The general function of RCMs is not the disconnecting of the power supply when a residual current above
the value of the rated residual operating current occurs. The RCM indicates the increase of the residual current
above the residual operating current with a signalling device, for example a lamp, buzzer, contact relay or interface-
signal. Thus the response time may only be tested via the visual or additional electrical detection of this signal.
According to IEC 62020 the response time of RCMs may only amount to a maximum of 10 s. The response time
shall be specified by the manufacturer or shall be adjustable on the device.
If the RCM is being used for the purpose of disconnection, the tests covered by IEC 61557-6
shall apply.
4.4 Operating conditions
The operating uncertainty applies according to the test conditions specified in IEC 61557-1 and
additionally
– the protective conductor is free of extraneous voltage,
– the system voltage remains constant during tests,
– the circuit behind the RCM is free of leakage currents,
– sinusoidal half-wave or full-wave current with rated frequency, respectively smooth direct
current (see 4.1),
– the a.c. test current I shall be switched on at a zero crossing,
T
– the test period shall be 10 s for the maximum test current for which the test equipment is
designed,
– the time limit may be omitted when testing with current higher than 500 mA,
– the resistance of the probes is within the limits stated by the manufacturer.
4.5 Prevention of danger by fault voltages exceeding 50 V a.c. or 120 V d.c. in the
monitored system during measurement
This can be achieved by the following:
– automatic disconnection in accordance with IEC 61010-1:2001, Figure 1, if the residual
voltage is above 50 V a.c. or 120 V d.c.;
– application of test current I , gradually or permanently adjustable, where the test starts a
T
maximum current of a.c. 3,5 mA or 15 mA d.c. in accordance with IEC 61010-1:2001, 6.3.2
b), including parallel test circuits, is permitted. The possibility to change the test current I
T
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SIST EN 61557-11:2009
61557-11 © IEC:2009 – 9 –
without generating a dangerous residual voltage shall be clearly identifiable, for instance on
a voltmeter.
In special locations the touch voltage limit is 25 V a.c or 60 V d.c.
The operating uncertainty for the detection of the fault voltage shall not exceed 0 % to –20 % of
the limit.
4.6 Prevention of danger caused by overvoltages when the system is connected
If the system is connected to 120 % of the nominal voltage of the system for which the test
equipment is designed, neither the operator shall be harmed nor the device be damaged.
Protective devices shall not be activated. If the device is intended to be used in IT systems, the
nominal voltage of the test equipment is the phase to phase voltage.
If the test equipment is accidentally connected to 173 % of the nominal voltage in TN or TT
systems for which the test equipment is designed for the duration of 1 min, neither the operator
shall be harmed nor the device be damaged. In this case, protective devices may be activated.
4.7 Electromagnetic compatibility (EMC)
The electromagnetic compatibility shall be in accordance with IEC 61326-2-2.
5 Marking and operating instructions
5.1 Markings
In addition to the marking in accordance with IEC 61557-1, the following information shall be
provided on the measuring equipment.
Rated residual operating current or rated residual operating currents of the RCM for which the
test equipment has been designed for an actuating time of 10 s.
NOTE Other rated residual operating currents for lower actuating times may be marked in addition.
5.2 Operating instructions
The operating instructions shall state the following in addition to the statements given in
IEC 61557-1.
5.2.1 Information
a) Information about special test configurations to avoid unintended tripping of RCDs (see
Annex B);
b) information to avoid unintended influences on the operation of the system;
c) information for recalibration cycles and safety tests of the test equipment after repair and
instructions for periodical tests.
5.2.2 Warnings
a) If the detecting circuit for the fault voltage has no probe and if a possible voltage between
the protecti
...