HD 50573-5-57:2014
(Main)Co-ordination of electrical equipment for protection, isolation, switching and control
Co-ordination of electrical equipment for protection, isolation, switching and control
This Harmonization Document specifies the requirements for the selection and erection of electrical equipments for protection, isolation, switching and control (hereafter referred to as electrical devices and assemblies) with respect to co-ordination. This Harmonization Document applies to electrical installations as detailed in HD 60364-1:2008, 11.1. The requirements of this document are additional to those specified in HD 60364. This Harmonization Document is intended to provide requirements for the safety of humans, livestock and property against danger and damage which may arise in the reasonable use of electrical installations and to specify requirements for the proper functioning of those installations. The requirements also cover aspects of continuity of supply of the installation. This part covers co-ordination in the case of a fault condition (e.g. short circuit, overload, residual currents) and also takes into consideration aspects of HD 60364-1:2008, 33.1 relevant to the co-ordination of electrical devices as follows : – overcurrent protective device (OCPD); – control and protective switching device (CPS); – residual current device (RCD); – contactor and starter; – switch and disconnector. NOTE 1 Co-ordination of monitoring devices is under consideration. NOTE 2 Reference to the meaning of the acronyms used in this document may be found in Table 57.1. This Harmonization Document does not provide requirements for the selection of an electrical device alone, but provides requirements for the selection of electrical devices to ensure electrical co-ordination between them.
Koordinierung elektrischer Einrichtungen
Coordination des dispositifs électriques
Le présent Document d’Harmonisation donne des règles relatives au choix et à la mise en œuvre des dispositifs électriques de protection, sectionnement, coupure et commande (appelés ci-après dispositifs électriques et assemblages) en respectant la coordination. Le présent Document d’Harmonisation s’applique aux installations électriques définies en 11.1 du HD 60364-1:2008. Les exigences du présent document s’ajoutent à celles de la série HD 60364. Le présent Document d’Harmonisation a pour but de définir des exigences concernant la sécurité des personnes, des animaux et des biens vis-à-vis des dangers et des dommages pouvant apparaître lors d'un usage raisonnable des installations électriques ; elle est également destinée à donner des règles régissant le fonctionnement approprié de ces installations. Les règles couvrent également les aspects de la continuité de l'alimentation de l'installation. La présente Partie couvre la coordination en cas de condition de défaut (par exemple court-circuit, surcharge, courants différentiels résiduels) et prend également en considération les aspects traités au 33.1 du HD 60364-1:2008 concernant la coordination des dispositifs électriques suivants : - dispositif de protection contre les surintensités (DPS) ; - appareil de connexion de commande et de protection (ACP) ; - dispositif à courant différentiel résiduel (DDR) ; - contacteurs et démarreurs ; - commutateurs et sectionneurs. NOTE 1 La coordination des dispositifs de surveillance est à l'étude. NOTE 2 Les références de la signification des acronymes utilisés dans le présent document peuvent être trouvées dans le Tableau 57.1. Le présent Document d’Harmonisation ne donne pas d'exigence concernant le choix d'un dispositif électrique en tant que tel, mais définit les exigences, relatives au choix des dispositifs électriques, destinées à assurer la coordination électrique entre eux.
Koordinacija električnih naprav
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST HD 50573-5-57:2014
01-april-2014
.RRUGLQDFLMDHOHNWULþQLKQDSUDY
Co-ordination of electrical equipment for protection, isolation, switching and control
Koordinierung elektrischer Einrichtungen
Coordination des dispositifs électriques
Ta slovenski standard je istoveten z: HD 50573-5-57:2014
ICS:
91.140.50 Sistemi za oskrbo z elektriko Electricity supply systems
SIST HD 50573-5-57:2014 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST HD 50573-5-57:2014
HARMONIZATION DOCUMENT
HD 50573-5-57
DOCUMENT D'HARMONISATION
February 2014
HARMONISIERUNGSDOKUMENT
ICS 91.140.50
English version
Co-ordination of electrical equipment for protection, isolation, switching
and control
Coordination des dispositifs électriques Koordinierung elektrischer Einrichtungen
This Harmonization Document was approved by CENELEC on 2013-12-30. CENELEC members are bound to
comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for implementation of this
Harmonization Document at national level.
Up-to-date lists and bibliographical references concerning such national implementations may be obtained on
application to the CEN-CENELEC Management Centre or to any CENELEC member.
This Harmonization Document exists in three official versions (English, French, German).
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany,
Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B - 1000 Brussels
© 2014 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. HD 50573-5-57:2014 E
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Contents
Foreword . 3
570 Co-ordination of electrical equipment for protection, isolation, switching and control . 4
570.1 Scope . 4
570.2 Normative references . 4
570.3 Terms and definitions . 5
571 Electrical devices considered and function provided. 8
572 Aspects of device co-ordination . 10
572.1 Basis of correct co-ordination . 10
572.2 Parameters . 10
572.3 Device co-ordination table . 10
573 Co-ordination requirements . 11
573.1 Requirements for selectivity . 12
573.1.1 General . 12
573.1.2 Selectivity under overload conditions between OCPDs . 12
573.1.3 Selectivity in short-circuit conditions between OCPDs . 13
573.1.4 Selectivity between RCDs . 14
573.1.5 Selectivity between OCPDs and RCDs . 15
573.2 Requirements for protection in case of short circuit . 17
573.2.1 Combined short-circuit protection of OCPDs . 17
573.2.2 Back-up protection of contactors or overload relays . 18
573.2.3 Back-up protection of switches, Transfer Switching Equipment (TSE) or impulse
relays. 21
573.2.4 Back-up protection of RCCB . 22
573.3 Requirements for protection in case of overload . 23
573.3.1 Overload protection of contactor or SCPDs . 23
573.3.2 Overload protection of RCCB, switch, Transfer Switching Equipment (TSE) or
impulse relay . 23
573.4 Requirements for selectivity between OCPDs equipped with under-voltage relay . 23
573.5 Low voltage assemblies according to EN 61439 series . 24
574 Documentation . 24
Bibliography . 26
Figures
Figure 57.1 – Selectivity between OCPDs . 12
Figure 57.2 – Selectivity between RCDs in case of residual current . 15
Figure 57.3 – Selectivity between OCPD and RCD using RCBOs . 15
Figure 57.4 – Selectivity between OCPD and RCD using RCCBs . 16
Figure 57.5 – Selectivity between upstream RCCB and RCBOs. . 17
Figure 57.6 – Typical configuration for combined short-circuit protection of OCPDs . 17
Figure 57.7 – Co-ordination between OCPD and contactor in case of short-circuit . 19
Figure 57.8 – Co-ordination of a contactor and overload relay with a OCPD . 20
Figure 57.9 – Co-ordination between OCPD and switch . 21
Figure 57.10 – Co-ordination between OCPD and RCCB . 22
Figure 57.11 – Selectivity with OCPD and undervoltage relays . 24
Tables
Table 57.1 – Devices and associated functions . 9
Table 57.2 – Device co-ordination in a LV electrical installation . 11
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Foreword
This document (HD 50573-5-57:2014) has been prepared by CLC/TC64 "Electrical installations and
protection against electric shock".
The following dates are fixed:
• latest date by which this document has to be
(dop) 2014-12-30
implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national standards conflicting
(dow) 2016-12-30
with this document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent rights.
During the design of an electrical installation, HD 60364 applies.
In an electrical installation, each device is required to comply with its relevant product standard according to
Clause 133.1 of HD 60364-1:2008 and to Clause 511 of HD 60364-5-51:2009.
It is also recognized that in an electrical installation, the combination of various device shall be selected
carefully so as not to impair safety. In case of a fault, the combination of several protective devices (circuit-
breakers, fuses, residual current devices…) may also affect the continuity of supply of the installation if the
upstream devices open, whereas the fault could be cleared by the downstream device.
This Harmonization Document is intended to bring complementary requirements to part 5 of HD 60364 for
selection and erection of electrical equipment, and cover aspects of co-ordination.
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570 Co-ordination of electrical equipment for protection, isolation, switching and
control
570.1 Scope
This Harmonization Document specifies the requirements for the selection and erection of electrical
equipments for protection, isolation, switching and control (hereafter referred to as electrical devices and
assemblies) with respect to co-ordination.
This Harmonization Document applies to electrical installations as detailed in HD 60364-1:2008, 11.1. The
requirements of this document are additional to those specified in HD 60364.
This Harmonization Document is intended to provide requirements for the safety of humans, livestock and
property against danger and damage which may arise in the reasonable use of electrical installations and to
specify requirements for the proper functioning of those installations. The requirements also cover aspects of
continuity of supply of the installation.
This part covers co-ordination in the case of a fault condition (e.g. short circuit, overload, residual currents)
and also takes into consideration aspects of HD 60364-1:2008, 33.1 relevant to the co-ordination of electrical
devices as follows :
– overcurrent protective device (OCPD);
– control and protective switching device (CPS);
– residual current device (RCD);
– contactor and starter;
– switch and disconnector.
NOTE 1 Co-ordination of monitoring devices is under consideration.
NOTE 2 Reference to the meaning of the acronyms used in this document may be found in Table 57.1.
This Harmonization Document does not provide requirements for the selection of an electrical device alone,
but provides requirements for the selection of electrical devices to ensure electrical co-ordination between
them.
570.2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
EN 60269 series, Low-voltage fuses (IEC 60269 series)
HD 60364-1:2008, Low-voltage electrical installations – Part 1: Fundamental principles, assessment of
general characteristics, definitions (IEC 60364-1:2005, mod.)
HD 60364-4-43:2010, Low-voltage electrical installations – Part 4-43: Protection for safety – Protection
against overcurrent (IEC 60364-4-43:2008, mod. + corrigendum Oct. 2008)
HD 60364-5-51:2009, Electrical installations of buildings – Part 5-51: Selection and erection of electrical
equipment – Common rules (IEC 60364-5-51:2005, mod.)
EN 60669-2-2, Switches for household and similar fixed electrical installations – Part 2-2: particular
requirements – Electromagnetic remote-control switches (RCS) (IEC 60069-2-2)
EN 60669-2-4, Switches for household and similar fixed electrical installations – Part 2-4: particular
requirements – Isolating switches (IEC 60669-2-4)
EN 60947-1, Low-voltage switchgear and controlgear – Part 1: General rules (IEC 60947-1)
EN 60947-2:2006, Low-voltage switchgear and controlgear – Part 2: Circuit-breakers (IEC 60947-2:2006)
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EN 60947-3, Low-voltage switchgear and controlgear – Part 3: switches, disconnectors, switch-disconnectors
and fuse-combination units (IEC 60947-3)
EN 60947-4-1, Low-voltage switchgear and controlgear – Part 4-1: Contactors and motor-starters –
Electromechanical contactors and motor starters (IEC 60947-4-1)
EN 60947-6-1, Low-voltage switchgear and controlgear – Part 6-1: multiple function equipment – Transfer
Switching Equipment (IEC 60947-6-1)
EN 60947-6-2, Low-voltage switchgear and controlgear – Part 6-2: multiple function equipment – Control and
protective switching devices (or equipment) (CPS) (IEC 60947-6-2)
EN 60898-1, Electrical accessories – Circuit breakers for overcurrent protection for household and similar
installations – Part 1: Circuit-breakers for a.c. operation (IEC 60898-1)
EN 60898-2, Electrical accessories – Circuit-breakers for overcurrent protection for household and similar
installations – Part 2: Circuit-breakers for a.c. and d.c. operation (IEC 60898-2)
EN 61008-2-1, Residual current operated circuit-breakers without integral overcurrent protection for
household and similar uses (RCCB’s) – Part 2-1: applicability of the general rules to rccb'S functionally
independent of line (IEC 61008-2-1)
EN 61009-2-1, Residual current operated circuit-breakers with integral overcurrent protection for household
and similar uses (RCBO's) – Part 2-1: applicability of the general rules to rcbo'S functionally independent of
line the voltage (IEC 61009-2-1)
EN 61095, Electromechanical contactors for household and similar purposes (IEC 61095)
EN 62423, Type B residual current operated circuit-breakers with and without integral overcurrent protection
for household and similar uses (Type B RCCBs and Type B RCBOs) (IEC 62423)
570.3 Terms and definitions
For the purpose of this document, the following terms and definitions apply.
570.3.1
co-ordination of electrical equipment
correct way of selecting electrical devices in series to ensure safety and continuity of service of the
installation taking into account short-circuit protection and/or overload protection and/or selectivity
570.3.2
safety of electrical installation
safety of human, livestock and property against danger and damage which may arise in the reasonable use
of electrical installations and which is covered by measures for:
– protection against electric shock;
– protection against thermal effects;
– protection against overcurrent;
– protection against fault currents;
– protection against voltage disturbances and measures against o electromagnetic influences;
– protection against power supply interruption where danger or damage is expected
Note 1 to entry: Continuity of supply may be necessary for certain circuits (e.g. circuits in medical locations, circuits
supplying emergency systems).
570.3.3
continuity of service
quality of an installation which is expressed by the extent to which the operation of an electrical system
approaches the ideal state of freedom from interruption, or which the operation of electrical system
minimizes supply interruption thanks to co-ordination of electrical devices
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570.3.4
back-up protection
overcurrent co-ordination, in short-circuit conditions, of an OCPD in series with another electrical device
where the OCPD, generally but not necessarily on the supply side, effects the overcurrent protection and
prevents any excessive stress on the electrical device
Note 1 to entry: Back-up protection does not cover the combined short-circuit protection.
570.3.5
combined short-circuit protection
overcurrent co-ordination, in short-circuit conditions, of two OCPDs in series, resulting in a combined short-
circuit current capability higher than one OCPD alone
570.3.6
combined short-circuit capability
maximum short-circuit current which can be handled by two short-circuit protective devices in series
570.3.7
selectivity
co-ordination of the operating characteristics of two or more protective devices such that, on the incidence of
overcurrents or residual currents within stated limits, the device intended to operate within these limits does
so, while the other(s) does (do) not
[SOURCE: IEV 441-17-15, modified]
Note 1 to entry: Distinction is made between series selectivity involving different overcurrent protective devices passing
substantially the same overcurrent and network selectivity involving protective devices passing different proportions of
the overcurrent.
570.3.8
total selectivity
selectivity where only the OCPD on the load side will operate up to the maximum prospective short-circuit
current at its point of installation
570.3.9
partial selectivity
selectivity where the OCPD on the load side only will operate up to a fault current (the selectivity limit
current) less than the maximum prospective short-circuit current at its point of installation
570.3.10
overcurrent protective device (OCPD)
device provided to interrupt an electric circuit in case the conductor current in the electric circuit exceeds a
predetermined value for a specified duration
[SOURCE: IEV 826-14-14]
Note 1 to entry: Table 57.1 provides information regarding the different devices corresponding to the main generic
function.
570.3.11
short-circuit protective device (SCPD)
device intended to protect a circuit or parts of a circuit against short-circuit currents by interrupting them
[SOURCE: EN 60947-1]
Note 1 to entry: Table 57.1 provides information regarding the different devices corresponding to the main generic
function.
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570.3.12
circuit-breaker
mechanical switching device, capable of making, carrying and breaking currents under normal circuit
conditions and also making, carrying for a specified time and breaking currents under specified abnormal
circuit conditions such as those of short circuit
[SOURCE: IEV 441-14-20]
Note 1 to entry: Table 57.1 provides information regarding the different devices corresponding to the main generic
function.
570.3.13
switch
device for changing the electric connections among its terminals
[SOURCE: IEV 151-12-22]
570.3.14
residual current device (RCD)
mechanical switching device designed to make, carry and break currents under normal service conditions
and to cause the opening of the contacts when the residual current attains a given value under specified
conditions
Note 1 to entry: A residual current device can be a combination of various separate elements designed to detect and
evaluate the residual current and to make and break current.
Note 2 to entry: RCD includes devices such as RCCB, RCBO, CBR and MRCD. Table 57.1 provides information
regarding the different devices corresponding to the main generic function.
[SOURCE: IEV 442-05-02, modified]
570.3.15
fuse
device that by the fusing of one or more of its specially designed and proportioned components, opens the
circuit in which it is inserted by breaking the current when this exceeds a given value for a sufficient time.
The fuse comprises all the parts that form the complete device
[SOURCE: IEV 441-18-01]
570.3.16
contactor
mechanical switching device having only one position of rest, operated otherwise than by hand, capable of
making, carrying and breaking currents under normal circuit conditions including operating overload
conditions
[SOURCE: IEV 441-14-33]
570.3.17
overload relay
overcurrent relay or release intended for protection against overloads
[SOURCE: EN 60947-1]
570.3.18
control and protective switching device (CPS)
switching device (or equipment) capable of operation other than by hand, but with or without local manual
operating means. A CPS device provides both functions of contactor and OCPD
[SOURCE: EN 60947-6-2 modified]
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570.3.19
conditional short-circuit current
prospective current that a circuit or a switching device, protected by a specified short-circuit protective
device, can satisfactorily withstand for the total operating time of that device under specified conditions of
use and behaviour
[SOURCE: EN 60947-1]
570.3.20
desk study
assessment of behaviour of devices connected in series, taking into account all relevant parameters
delivered by manufacturer such as:
– design current;
– prospective short-circuit or fault current;
– operating time of devices;
– system voltage;
– energy (let through I²t values);
– peak let through current
571 Electrical devices considered and function provided
Table 57.1 shows the function provided by the different electrical devices considered in this Harmonization
Document.
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Table 57.1 – Devices and associated functions
Devices Functions
Product Standard Overload Short- Residual Switching
Protection Circuit Current only
Protection Protection
Circuit-Breaker X EN 60947-2 X X - -
EN 60898-1
EN 60898-2
RCCB X EN 61008-2-1 - - X -
Residual current EN 62423
operated circuit-
breakers without
integral
overcurrent
protection
RCBO X X EN 61009-2-1 X X X -
Residual current EN 62423
operated circuit-
breakers with
integral
overcurrent
protection
CBR X X EN 60947-2:2006, X X X -
Circuit-breakers Annex B
providing residual
current protection
MRCD X X EN 60947-2:2006, X X X -
Modular Residual Annex M
(3)
current device
ICB X EN 60947-2:2006, - X - -
Instantaneous trip Annex O
circuit-breakers
Fuse with full X EN 60269 X X - -
range breaking
series
capacity (e.g. gG,
(1)
gM)
Fuse with partial X EN 60269 - X - -
range breaking
series
capacity (e.g. aM)
(1)
CPS X EN 60947-6-2 X X - -
Control and
Protective
Switching Devices
Contactor EN 60947-4-1 - - - X
EN 61095
Overload relay EN 60947-4-1 X - - -
Switch or switch- EN 60947-3 - - -
disconnector
EN 60669-2-2 X
EN 60669-2-4
TSE - - -
Transfer EN 60947-6-1 X
Switching
Equipment
(2)
OCPD
(2)
SCPD
(2)
RCD
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(1)
fuse combination units according to EN 60947-3 are considered in this row
(2)
generic acronyms used in this document for devices
(3)
when associated with a circuit-breaker
572 Aspects of device co-ordination
572.1 Basis of correct co-ordination
The basis of the co-ordination between electrical equipment is to take advantage of the correct combination
of their electrical characteristics in order not to impair:
– the safety of an installation (i.e. to avoid equipment combustion due to an electrical fault);
Combined short-circuit protection of OCPDs and back-up protection by an OCPD relates to the
safety of an installation.
– the safety due to continuity of service, if needed (i.e. to restrict the disconnection to the faulty circuit
in case of overcurrent or fault to earth).
Selectivity between electrical devices provides continuity of service and thus avoids dangers linked
to the loss of supply of specific circuits.
572.2 Parameters
The parameters for the correct co-ordination between electrical devices may be:
– design current;
– prospective short-circuit or fault current;
– operating time of devices;
– system voltage;
– energy (let through I²t values);
– peak let through current.
In addition, for fuses, the following parameters shall be considered :
– pre-arcing I²t and pre- arcing time;
– operating I²t and operating time.
572.3 Device co-ordination table
Table 57.2 shows the types of combination of devices and cells show how various modes of co-ordination
affect safety.
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Table 57.2 – Device co-ordination in a LV electrical installation
Impact on
safety due
Clause Modes of co- Devices involved Impact on
to
ordination safety of
continuity
installation
of service
573.1.2
Between OCPDs X
573.1.3
573.1.4 Selectivity Between RCDs X
573.1.5 Between OCPD and RCD X
Combined Short-
573.2.1 OCPDs X
circuit protection
Between OCPD and
573.2.2 contactors, X
Current or overload relay
time based
Back-up protection
Between OCPD and
conditions
in case of short
573.2.3 switches, TSE or X
circuit
impulse relays
573.2.4 Between OCPD and RCCB X
Between OCPD and
573.3.1 X
contactor or SCPD
Between OCPD and
Protection in case of
573.3.2 switches, TSE or X
overload
impulse relays
573.3.2 Between OCPD and RCCB X
Voltage based Between OCPDs equipped
573.4 Selectivity X
conditions with under-voltage relay
573 Co-ordination requirements
For selecting electrical devices as covered by the following clauses, the mutual interaction between those
devices shall be considered so that they do not adversely affect the safety of the installation.
The co-ordination of electrical devices considers requirements in case of:
– short-circuit;
– overload;
– residual currents.
Aspects for co-ordination of electrical devices are:
– selectivity;
– short-circuit protection;
– overload protection.
Electrical devices shall be selected taking into account the co-ordination characteristics as given by the
manufacturers.
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573.1 Requirements for selectivity
573.1.1 General
Selectivity between OCPDs is defined in 573.1.2 for overload conditions and in 573.1.3 for short-circuit
conditions. Selectivity between RCDs is defined in 573.1.4 and selectivity between OCPD and RCD is
defined in 573.1.5.
In this clause, the OCPD could be replaced by an SCPD.
573.1.2 Selectivity under overload conditions between OCPDs
573.1.2.1 General requirements
When selectivity is required, as shown in Figure 57.1, verification shall be made either:
– by desk study taking into account the relevant product standard and the manufacturer’s literature; or
– by appropriate software tools where information is provided by the manufacturers for this specific
use; or
– by tests in accordance with the applicable product standard (in order to ensure the correct test
performances and reproducibility); or
– by manufacturer’s declaration.
In case of desk study, when time/current characteristics are used to verify selectivity, account should be
taken of the reference ambient temperature for which the tripping curves are given and to load condition
before the overcurrent.
O
C
P
D
1
O O
C C
P P
D D
21 22
Figure 57.1 – Selectivity between OCPDs
573.1.2.2 Between circuit-breakers or circuit breaker and CPS or circuit-breaker and overload relay
or circuit-breaker and motor starter
Selectivity in case of overload (see 826-11-15) is verified by the comparison of time/current characteristics of
the devices involved. The maximum operating time of the device on the load side shall be lower than the
non-tripping time of the circuit-breaker for any overload current. Separation of the characteristics in both the
time and current axes ensures selective operation in this zone.
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573.1.2.3 Between fuses
Selectivity in case of overload is verified by the comparison of time/current characteristics of the fuses
involved. The total operating time of the fuse on the load side shall be lower than the pre-arcing time of the
fuse on the supply side. Fuses to EN 60269-1 of the same utilisation category (e.g. type gG) with rated
current of 16 A and above, will provide total selectivity if the ratio of the rated currents is 1,6:1 or greater.
Separation of the characteristics in both the time and current axes ensures selective operation in this zone.
573.1.2.4 Between circuit-breaker (upstream) and fuse (downstream)
Selectivity in case of overload is verified by comparison of the time/current characteristics, taking into
account the trip settings of the circuit-breaker where applicable. The maximum operating time of the fuse as
given by the product standard shall be lower than the minimum tripping time of the circuit-breaker as given
by the manufacturer. Separation of the characteristics in both the time and current axes ensures selective
operation in this zone.
573.1.2.5 Between fuse (upstream) and circuit-breaker (downstream)
Selectivity in cas
...
SLOVENSKI STANDARD
oSIST prHD 50573-5-57:2013
01-januar-2013
.RRUGLQDFLMDHOHNWULþQLKQDSUDY
Electrical devices coordination
Koordinierung elektrischer Einrichtungen
Coordination des dispositifs électriques
Ta slovenski standard je istoveten z: prHD 50573-5-57:2012
ICS:
91.140.50 Sistemi za oskrbo z elektriko Electricity supply systems
oSIST prHD 50573-5-57:2013 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prHD 50573-5-57:2013
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oSIST prHD 50573-5-57:2013
DRAFT
HARMONIZATION DOCUMENT
prHD 50573-5-57
DOCUMENT D'HARMONISATION
November 2012
HARMONISIERUNGSDOKUMENT
ICS
English version
Electrical devices coordination
Coordination des dispositifs électriques Koordinierung elektrischer Einrichtungen
This draft Harmonization Document is submitted to CENELEC members for CENELEC enquiry.
Deadline for CENELEC: 2013-04-12.
It has been drawn up by CENELEC TC 64.
If this draft becomes a Harmonization Document, CENELEC members are bound to comply with the
CEN/CENELEC Internal Regulations which stipulate the conditions for implementation of this Harmonization
Document on a national level.
This draft Harmonization Document was established by CENELEC in three official versions (English, French,
German).
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany,
Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of
which they are aware and to provide supporting documentation.
Warning : This document is not a Harmonization Document. It is distributed for review and comments. It is
subject to change without notice and shall not be referred to as a Harmonization Document.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Management Centre: Avenue Marnix 17, B - 1000 Brussels
© 2012 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Project: 22526 Ref. No. prHD 50573-5-57:2012 E
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1 Contents
2 Foreword . 4
3 570 Coordination of electrical equipment for protection, isolation, switching and control . 5
4 570.1 Scope . 5
5 570.2 Normative references . 5
6 570.3 Terms and definitions . 6
7 571 Electrical devices considered and function provided. 9
8 572 Aspects of device coordination . 11
9 572.1 Basis of correct coordination . 11
10 572.2 Parameters . 11
11 572.3 Device coordination table . 11
12 573 Coordination requirements . 12
13 573.1 Requirements for selectivity . 13
14 573.1.1 Selectivity under overload conditions between OCPDs . 13
15 573.1.2 Selectivity in short-circuit conditions between OCPDs . 14
16 573.1.3 Selectivity between RCDs . 15
17 573.1.4 Selectivity between OCPDs and RCDs . 16
18 573.2 Requirements for protection in case of short circuit . 18
19 573.2.1 Combined short-circuit protection of SCPDs . 18
20 573.2.2 Back up protection of contactors or overload relays . 19
21 573.2.3 Back up protection of switches, Transfer Switches Equipments (TSE) or impulse
22 relays (code B3) . 21
23 573.2.4 Back up protection of RCCB . 22
24 573.3 Requirements for protection in case of overload . 22
25 573.3.1 Overload protection of contactor or SCPDs . 22
26 573.3.2 Overload protection of RCCB, switch or TSE . 23
27 573.4 Requirements for selectivity between OCPDs equipped with under-voltage relay . 23
28 574 Documentation . 24
29 Bibliography . 25
30
31 Figures
32 Figure 57.1 – Selectivity between OCPDs . 13
33 Figure 57.2 – Selectivity between RCDs in case of residual current . 16
34 Figure 57.3 – Selectivity between OCPD and RCD using RCBOs . 16
35 Figure 57.4 – Selectivity between OCPD and RCD using RCCBs . 17
36 Figure 57.5 – Selectivity between upstream RCCB and RCBOs. . 18
37 Figure 57.6 – Typical configuration for combined short-circuit protection of SCPDs . 18
38 Figure 57.7 – Coordination between SCPD and contactor in case of short-circuit . 19
39 Figure 57.8 – Coordination of a contactor and overload relay with a SCPD . 20
40 Figure 57.9 – Coordination between SCPD and switch . 21
41 Figure 57.10 – Coordination between SCPD and RCCB . 22
42 Figure 57.11 – Selectivity with OCPD and undervoltage relays . 24
43
44 Tables
45 Table 57.1 – Function provided by the different devices . 10
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46 Table 57.2 – Device coordination in a LV electrical installation . 12
47
48
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49 Foreword
50 This document (prHD 50573-5-57:2012) has been prepared by CLC /TC64 "Electrical installations and
51 protection against electric shock".
52 This document is currently submitted to the second Enquiry.
53 During the design of an electrical installation, HD 60364 applies.
54 In an electrical installation, each device is required to comply with its relevant product standard according to
55 clause 133.1 of HD 60364-1:2008 and to clause 511 of HD 60364-5-51:2009.
56 It is also recognised that in an electrical installation, the combination of various device shall be selected
57 carefully so as not to impair safety. In case of a fault, the combination of several protective devices (circuit-
58 breakers, fuses, residual current devices…) may also affect the continuity of supply of the installation if the
59 upstream devices open, whereas the fault could be cleared by the downstream device.
60 This standard is intended to bring complementary rules to part 5 of HD 60364 for selection and erection of
61 electrical equipment, and cover aspects of coordination.
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62 570 Coordination of electrical equipment for protection, isolation, switching and
63 control
64 570.1 Scope
65 This European Standard specifies the rules for the selection and erection of electrical equipments for
66 protection, isolation, switching and control (hereafter referred to as electrical devices and assemblies) with
67 respect to coordination.
68 This European Standard applies to electrical installations as detailed in HD 60364-1 clause 11.1.
69 This European Standard is intended to provide requirements for the safety of humans, livestock and property
70 against danger and damage which may arise in the reasonable use of electrical installations and to specify
71 rules for the proper functioning of those installations. The rules also cover aspects of continuity of supply of
72 the installation.
73 This part covers coordination in the case of a fault condition (e.g. short circuit, overload, residual currents)
74 and also takes into consideration aspects of HD 60364-1 clause 33.1 relevant to the coordination of electrical
75 devices as follows :
76 – overcurrent protective device (OCPD);
77 – control and protective switching device (CPS);
78 – residual current device (RCD);
79 – contactor and starter;
80 – switch and disconnector.
81 NOTE 1 Coordination of monitoring devices is under consideration.
82 NOTE 2 Reference to the meaning of the acronyms used in this document may be found in Table 57.1.
83 This European Standard does not provide requirements for the selection of an electrical device alone, but
84 provides requirements for the selection of electrical devices to ensure electrical coordination between them.
85 570.2 Normative references
86 The following documents, in whole or in part, are normatively referenced in this document and are
87 indispensable for its application. For dated references, only the edition cited applies. For undated references,
88 the latest edition of the referenced document (including any amendments) applies.
EN 60269 series, Low-voltage fuses
HD 60364-1:2008, Low-voltage electrical installations – Part 1: Fundamental principles, assessment of
general characteristics, definitions (IEC 60364-1:2005, mod.)
HD 60364-4-43:2010, Low-voltage electrical installations – Part 4-43: Protection for safety – Protection
against overcurrent (IEC 60364-4-43:2008 + corrigendum Oct. 2008)
HD 60364-5-51:2009, Electrical installations of buildings – Part 5-51: Selection and erection of electrical
equipment – Common rules (IEC 60364-5-51:2005, mod.)
EN 60669-2-2, Switches for household and similar fixed electrical installations - Part 2-2: particular
requirements - Electromagnetic remote-control switches (RCS)
EN 60669-2-4, Switches for household and similar fixed electrical installations - Part 2-4: particular
requirements - Isolating switches
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EN 60947-1, Low-voltage switchgear and controlgear – Part 1: General rules
EN 60947-2, Low-voltage switchgear and controlgear – Part 2: Circuit-breakers
EN 60947-3, Low-voltage switchgear and controlgear - Part 3 : switches, disconnectors, switch-disconnectors
and fuse-combination units
EN 60947-4-1, Low-voltage switchgear and controlgear – Part 4-1: Contactors and motor-starters –
Electromechanical contactors and motor starters
EN 60947-6-1, Low-voltage switchgear and controlgear - Part 6-1 : multiple function equipment - Transfer
Switching Equipment
EN 60947-6-2, Low-voltage switchgear and controlgear - Part 6-2 : multiple function equipment - Control and
protective switching devices (or equipment) (CPS)
EN 60898-1, Electrical accessories – Circuit breakers for overcurrent protection for household and similar
installations – Part 1: Circuit-breakers for a.c. operation
EN 60898-2, Electrical accessories – Circuit-breakers for overcurrent protection for household and similar
installations – Part 2: Circuit-breakers for a.c. and d.c. operation
EN 61008-1, Residual current operated circuit-breakers without integral overcurrent protection for household
and similar uses (RCCB's) – Part 1: General rules
EN 61008-2-1, Residual current operated circuit-breakers without integral overcurrent protection for
household and similar uses (RCCB’s). Part 2-1 : applicability of the general rules to rccb'S functionally
independent of line
EN 61009-1, Residual current operated circuit-breakers with integral overcurrent protection for household
and similar uses (RCBO's) – Part 1: General rules
EN 61009-2-1, Residual current operated circuit-breakers with integral overcurrent protection for household
and similar uses (RCBO's). Part 2-1 : applicability of the general rules to rcbo'S functionally independent of
line the voltage
EN 61095, Electromechanical contactors for household and similar purposes
EN 62423, Type B residual current operated circuit-breakers with and without integral overcurrent protection
for household and similar uses (Type B RCCBs and Type B RCBOs)
IEC 60050-151, International Electrotechnical Vocabulary – Part 151: Electrical and magnetic devices
IEC 60050-441, International Electrotechnical Vocabulary – Part 441: Switchgear, controlgear and fuses
IEC 60050-442, International Electrotechnical Vocabulary – Part 442: Electrical accessories
IEC 60050-826, International Electrotechnical Vocabulary – Part 826: Electrical installations
89
90 570.3 Terms and definitions
91 For the purpose of this document, the following terms and definitions apply.
92 570.3.1
93 coordination of electrical equipment
94 correct way of using electrical devices in series to ensure safety and continuity of service of the installation
95 taking into account short-circuit protection and/or overload protection and/or selectivity
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96 570.3.2
97 safety of electrical installation
98 safety of human, livestock and property against danger and damage which may arise in the reasonable use
99 of electrical installations and which is covered by measures for:
100 – protection against electric shock;
101 – protection against thermal effects;
102 – protection against overcurrent;
103 – protection against fault currents;
104 – protection against voltage disturbances and measures against o electromagnetic influences;
105 – protection against power supply interruption where danger or damage is expected.
106 Note 1 to entry: Continuity of supply may be necessary for certain circuits (e.g. circuits in medical locations, circuits
107 supplying emergency systems).
108 570.3.3
109 continuity of service
110 quality of an installation which is expressed by the extent to which the operation of an electrical system
111 approaches the ideal state of freedom from interruption, or which the operation of electrical system
112 minimizes supply interruption thanks to coordination of electrical devices
113 570.3.4
114 back-up protection
115 over-current coordination of a SCPD in series with another electrical device where the SCPD, generally but
116 not necessarily on the supply side, effects the over-current protection and prevents any excessive stress on
117 the electrical device
118 Note 1 to entry: Back-up protection does not cover the combined short-circuit protection.
119 570.3.5
120 combined short-circuit protection
121 over-current coordination of two SCPDs in series, resulting in a combined short-circuit current capability
122 higher than one SCPD alone
123 570.3.6
124 combined short-circuit capability
125 maximum short-circuit current which can be handled by two short-circuit protective devices in series
126 570.3.7
127 selectivity
128 coordination of the operating characteristics of two or more protective devices such that, on the incidence of
129 overcurrents or residual currents within stated limits, the device intended to operate within these limits does
130 so, while the other(s) does (do) not
131 [SOURCE: IEV 441-17-15, modified]
132 Note 1 to entry: Distinction is made between series selectivity involving different overcurrent protective devices passing
133 substantially the same overcurrent and network selectivity involving identical protective devices passing different
134 proportions of the overcurrent.
135 570.3.8
136 total selectivity
137 selectivity where only the OCPD on the load side will operate up to the maximum prospective short-circuit
138 current at its point of installation
139 570.3.9
140 partial selectivity
141 selectivity where the OCPD on the load side only will operate up to a fault current (the selectivity limit
142 current) less than the maximum prospective short-circuit current at its point of installation
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143 570.3.10
144 switchgear and assembly
145 electric equipment intended to be connected to an electric circuit for the purpose of carrying out one or more
146 of the following functions: protection, control, isolation, switching
147 Modified [826-16-03]
148 570.3.11
149 overcurrent protective device (OCPD)
150 device provided to interrupt an electric circuit in case the conductor current in the electric circuit exceeds a
151 predetermined value for a specified duration.
152 [SOURCE: IEV 826-14-14]
153 Note 1 to entry: Table 57.1 provides information regarding the different devices corresponding to the main generic
154 function.
155 570.3.12
156 short-circuit protective device (SCPD)
157 device intended to protect a circuit or parts of a circuit against short-circuit currents by interrupting them
158 [SOURCE: EN 60947-1]
159 Note 1 to entry: Table 57.1 provides information regarding the different devices corresponding to the main generic
160 function.
161 570.3.13
162 circuit-breaker
163 mechanical switching device, capable of making, carrying and breaking currents under normal circuit
164 conditions and also making, carrying for a specified time and breaking currents under specified abnormal
165 circuit conditions such as those of short circuit.
166 [SOURCE: IEV 441-14-20]
167 Note 1 to entry: Table 57.1 provides information regarding the different devices corresponding to the main generic
168 function.
169 570.3.14
170 switch
171 device for changing the electric connections among its terminals
172 [SOURCE: IEV 151-12-22]
173 570.3.15
174 residual current device (RCD)
175 mechanical switching device designed to make, carry and break currents under normal service conditions
176 and to cause the opening of the contacts when the residual current attains a given value under specified
177 conditions
178 Note 1 to entry: A residual current device can be a combination of various separate elements designed to detect and
179 evaluate the residual current and to make and break current.
180 Note 2 to entry: RCD includes devices such as RCCB, RCBO, CBR and MRCD. Table 57.1 provides information
181 regarding the different devices corresponding to the main generic function.
182 [SOURCE: IEV 442-05-02, modified]
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183 570.3.16
184 fuse
185 device that by the fusing of one or more of its specially designed and proportioned components, opens the
186 circuit in which it is inserted by breaking the current when this exceeds a given value for a sufficient time.
187 The fuse comprises all the parts that form the complete device
188 [SOURCE: IEV 441-18-01]
189 570.3.17
190 contactor
191 mechanical switching device having only one position of rest, operated otherwise than by hand, capable of
192 making, carrying and breaking currents under normal circuit conditions including operating overload
193 conditions
194 [SOURCE: IEV 441-14-33]
195 570.3.18
196 overload relay
197 over-current relay or release intended for protection against overloads
198 [SOURCE: EN 60947-1]
199 570.3.19
200 control and protective switching device (CPS)
201 switching device (or equipment) capable of operation other than by hand, but with or without local manual
202 operating means. A CPS device provides both functions of contactor and OCPD
203 [SOURCE: EN 60947-6-2 modified]
204 570.3.20
205 conditional short-circuit current
206 prospective current that a circuit or a switching device, protected by a specified short-circuit protective
207 device, can satisfactorily withstand for the total operating time of that device under specified conditions of
208 use and behaviour
209 [SOURCE: EN 60947-1]
210 571 Electrical devices considered and function provided
211 Table 57.1 shows the function provided by the different electrical devices considered in this standard marked
212 “X”.
213
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214 Table 57.1 – Function provided by the different devices
Device Standard Overload Short- Residual Switching
Protection Circuit Current only
Protection Protection
Circuit-Breaker OCPD EN 60947-2
EN 60898-1
SCPD X X - -
EN 60898-2
RCCB RCD EN 61008-2-1
EN 62423
Residual current
operated circuit-
- - X -
breakers without
integral overcurrent
protection
RCBO OCPD EN 61009-2-1
EN 62423
Residual current SCPD -
X X X
operated circuit-
RCD
breakers with integral
overcurrent protection
CBR OCPD EN 60947-2,
Annex B
Circuit-breakers SCPD -
X X X
providing residual
RCD
current protection
ICB SCPD EN 60947-2
Annex O
Instantaneous trip -
- X -
circuit-breakers
Fuse with full range OCPD EN 60269
breaking capacity X X -
series
(1)
SCPD -
(e.g. gG, gM)
Fuse with partial SCPD EN 60269
range breaking - X - -
series
(1)
capacity (e.g. aM)
CPS OCPD EN 60947-6-2
X X - -
Control and Protective SCPD
Switching Devices
Contactor EN 60947-4-1 X
- - -
EN 61095
Overload relay EN 60947-4-1 X - - -
Switch or switch- EN 60947-3
disconnector
- - -
EN 60669-2-2
X
EN 60669-2-4
ATSE
EN 60947-6-1 - - -
Automatic Transfer X
Switching Equipment
(1)
fuse combination units according to EN 60947-3 are considered in this row
215
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216 572 Aspects of device coordination
217 572.1 Basis of correct coordination
218 The basis of the coordination between electrical equipment is to take advantage of the correct combination
219 of their electrical characteristics in order not to impair:
220 – the safety of an installation (i.e. to avoid equipment combustion due to an electrical fault);
221 Combined short-circuit protection of SCPDs and back-up protection by an OCPD relates to the
222 safety of an installation.
223 – the safety due to continuity of service, if needed (i.e. to restrict the disconnection to the faulty circuit
224 in case of over-current or fault to earth).
225 Selectivity between electrical devices provides continuity of service and thus avoids dangers linked
226 to the loss of supply of specific circuits.
227 572.2 Parameters
228 The parameters for the correct coordination between electrical devices may be:
229 – design current;
230 – prospective short-circuit or fault current;
231 – operating time of devices;
232 – system voltage;
233 – energy (let through I²t values);
234 – peak let through current.
235 572.3 Device coordination table
236 Table 57.2 shows the types of combination of devices and cells marked with “X” show how various modes of
237 coordination affect safety.
238
239
240
241
242
243
244
245
246
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247 Table 57.2 – Device coordination in a LV electrical installation
Impact on
safety due
Clause Modes of Devices involved Impact on
to
coordination safety of
continuity
installation
of service
573.1.1
Between OCPDs X
573.1.2
573.1.3 BSelectivity etween RCDs X
573.1.4 Between OCPD and RCD X
Combined Short-
573.2.1 SCPDs X
circuit protection
Between SCPD and
573.2.2 contactors, X
Current or
overload relay
time based
conditions Back-up protection
Between SCPD and switches
in case of short
573.2.3 X
or impulse relays
circuit
573.2.4 Between SCPD and RCCB X
Between OCPD and
573.3.1 X
contactor or SCPD
Protection in case of
573.3.2 Between OCPD and switches X
overload
573.3.2 Between OCPD and RCCB X
Voltage based Between OCPDs equipped
573.4 Selectivity X
conditions with under-voltage relay
248
249 NOTE When selectivity between RCD and Modular Residual Current Device (MRCD complying with EN 60947-2
250 Annex M) is required, the requirements of this standard clause 573.1.3 may be used.
251 573 Coordination requirements
252 For selecting electrical devices as covered by the following clauses, the mutual interaction between those
253 devices shall be considered so that they do not adversely affect the safety of the installation.
254 The coordination of electrical devices considers requirements in case of:
255 – short-circuit;
256 – overload;
257 – residual currents.
258 Aspects for coordination of electrical devices are:
259 – selectivity;
260 – short-circuit protection;
261 – overload protection.
262 Electrical devices shall be selected taking into account the coordination characteristics as given by the
263 manufacturers.
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264 573.1 Requirements for selectivity
265 Selectivity between OCPDs is defined in 573.1.1 for overload conditions and in 573.1.2 for short-circuit
266 conditions. Selectivity between RCDs is defined in 573.1.3 and selectivity between SCPD and RCD is
267 defined in 573.1.4.
268 573.1.1 Selectivity under overload conditions between OCPDs
269 573.1.1.1 General requirements
270 When selectivity is required, as shown in Figure 57.1, verification shall be made either:
271 – by desk study taking into account the relevant product standard and the manufacturer’s literature; or
272 – by appropriate software tools where information is provided by the manufacturers for this specific
273 use; or
274 – by tests in accordance with the applicable product standard (in order to ensure the correct test
275 performances and reproducibility); or
276 – by manufacturer’s declaration.
277 NOTE In case of desk study, when tripping curves are used to verify selectivity, account should be taken of the
278 reference temperature for which the tripping curves are given and to load condition before the overcurrent.
279
280 Figure 57.1 – Selectivity between OCPDs
281 573.1.1.2 Between circuit-breakers or circuit breaker and CPS or circuit-breaker and overload relay
282 or circuit-breaker and motor starter
283 Selectivity in case of overload (see 826-11-15) is verified by the comparison of time/current characteristics of
284 the devices involved. The maximum operating time of the device on the load side shall be lower than the
285 minimum operating time of the circuit-breaker on the supply side. Separation of the characteristics in both
286 the time and current axes ensures selective operation in this zone.
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287 573.1.1.3 Between fuses
288 Selectivity in case of overload is verified by the comparison of time/current characteristics of the fuses
289 involved. The total operating time of the fuse on the load side shall be lower than the pre-arcing time of the
290 fuse on the supply side. Fuses to IEC 60269-1 of the same type designation (e.g. type gG) with rated
291 currents above 16 A, will provide total selectivity if the ratio of the rated currents is 1,6:1 or greater.
292 Separation of the characteristics in both the time and current axes ensures selective operation in this zone.
293
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