IEC 60364-5-53:2019

Low-voltage electrical installations - Part 5-53: Selection and erection of electrical equipment - Devices for protection for safety, isolation, switching, control and monitoring

IEC 60364-5-53:2019 Deals with general requirements for isolation, switching and control and with the requirements for selection and erection of the devices provided to fulfil such functions. This fourth edition cancels and replaces the third edition published in 2001, Amendment 1:2002 and Amendment 2:2015. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) revision of all clauses except 531 and 534;
b) introduction of a new Clause 537 Monitoring;
c) Clause 530 contains all normative references and all terms and definitions.

Installations électriques à basse tension - Partie 5-53: Choix et mise en œuvre des matériels électriques – Dispositifs de protection pour assurer la sécurité, le sectionnement, la coupure, la commande et la surveillance

L'IEC 60364-5-53:2019 traite des exigences relatives:
a) au sectionnement, à la coupure, à la commande et à la surveillance, et
b) au choix et à la mise en œuvre des:
1) dispositifs pour le sectionnement, la coupure, la commande et la surveillance, et
2) dispositifs pour assurer la conformité aux mesures de protection en vue de la sécurité.
Cette quatrième édition annule et remplace la troisième édition parue en 2001, l’Amendement 1:2002 et l’Amendement 2:2015. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) révision de tous les articles à l’exception des articles 521 et 534;
b) introduction d’un nouvel Article 537, Surveillance;
c) l’Article 530 contient toutes les références normatives et l’ensemble des termes et définitions.

General Information

• Status: Published
• Publication Date: 20-Feb-2019
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.130.01 - Switchgear and controlgear in general
• ICS: 91.140.50 - Electricity supply systems
• Technical Committee: TC 64 - Electrical installations and protection against electric shock
• Current Stage: PPUB - Publication issued
• Completion Date: 21-Feb-2019

Standards Content (Sample)

IEC 60364-5-53
Edition 4.0 2019-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Low-voltage electrical installations –
Part 5-53: Selection and erection of electrical equipment – Devices
for protection for safety, isolation, switching, control and monitoring
Installations électriques à basse tension –
Partie 5-53: Choix et mise en œuvre des matériels électriques – Dispositifs
de protection pour assurer la sécurité, le sectionnement, la coupure,
la commande et la surveillance
IEC 60364-5-53:2019-02(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60364-5-53
Edition 4.0 2019-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Low-voltage electrical installations –
Part 5-53: Selection and erection of electrical equipment – Devices
for protection for safety, isolation, switching, control and monitoring
Installations électriques à basse tension –
Partie 5-53: Choix et mise en œuvre des matériels électriques – Dispositifs
de protection pour assurer la sécurité, le sectionnement, la coupure,
la commande et la surveillance
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.130.01; 91.140.50 ISBN 978-2-8322-7598-6

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 60364-5-53:2019 © IEC 2019
CONTENTS

FOREWORD ........................................................................................................................... 6

530.1 Scope ..................................................................................................................... 8

530.2 Normative references .............................................................................................. 8

530.3 Terms and definitions ............................................................................................ 11

530.4 General and common requirements....................................................................... 14

530.5 Erection of equipment ........................................................................................... 14

531 Devices for protection against indirect contact by automatic disconnection of

supply............................................................................................................................ 14

531.1 Overcurrent protective devices .............................................................................. 14

531.1.1 TN systems ................................................................................................... 14

531.1.2 TT systems .................................................................................................... 14

531.1.3 IT systems ..................................................................................................... 15

531.2 Residual current protective devices....................................................................... 15

531.2.1 General conditions of installation ................................................................... 15

531.2.2 Selection of devices according to their method of application ........................ 15

531.2.3 TN systems ................................................................................................... 15

531.2.4 TT systems .................................................................................................... 16

531.2.5 IT systems ..................................................................................................... 16

531.3 Insulation monitoring devices ................................................................................ 16

532 Devices and precautions for protection against thermal effects ...................................... 16

532.1 General ................................................................................................................. 16

532.2 Locations with a particular risk of fire .................................................................... 16

532.2.1 General ......................................................................................................... 16

532.2.2 Locations with external influences BD2, BD3 or BD4 ..................................... 17

532.2.3 Locations with external influences BE2 .......................................................... 17

532.3 Selection of arc fault detection devices (AFDD) .................................................... 18

533 Devices for protection against overcurrent ..................................................................... 18

533.1 General requirements ........................................................................................... 18

533.1.1 General ......................................................................................................... 18

533.1.2 Compliance with standards ............................................................................ 18

533.1.3 Fuses ............................................................................................................ 19

533.2 Selection of devices for protection against overload current .................................. 19

533.2.1 General ......................................................................................................... 19

533.2.2 Presence of harmonic currents ...................................................................... 20

533.2.3 Unequal current sharing between parallel conductors .................................... 20

533.3 Selection of devices for protection against short-circuit current ............................. 20

533.3.1 Thermal stresses ........................................................................................... 20

533.3.2 Breaking capacity .......................................................................................... 21

533.4 Positioning of overcurrent protection devices ........................................................ 21

533.4.1 General ......................................................................................................... 21

533.4.2 Positioning of devices for overload protection ................................................ 21

533.4.3 Positioning of devices for short-circuit protection ........................................... 22

533.5 Co-ordination of overload and short-circuit protective functions............................. 23

533.5.1 Protective functions provided by one device .................................................. 23

533.5.2 Protective functions provided by separate devices ......................................... 23

534 Devices for protection against transient overvoltages .................................................... 23

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IEC 60364-5-53:2019 © IEC 2019 – 3 –

534.1 General ................................................................................................................. 23

534.2 Void ...................................................................................................................... 24

534.3 Void ...................................................................................................................... 24

534.4 Selection and erection of SPDs ............................................................................. 24

534.4.1 SPD location and SPD test class ................................................................... 24

534.4.2 Transient overvoltage protection requirements .............................................. 25

534.4.3 Connection types ........................................................................................... 25

534.4.4 Selection of SPDs .......................................................................................... 27

534.4.5 Protection of the SPD against overcurrent ..................................................... 31

534.4.6 Fault protection ............................................................................................. 33

534.4.7 SPDs installation in conjunction with RCDs.................................................... 34

534.4.8 Connections of the SPD ................................................................................. 34

534.4.9 Effective protective distance of SPDs ............................................................ 36

534.4.10 Connecting conductors of SPDs .................................................................... 37

535 Co-ordination of protective devices ................................................................................ 37

535.1 Selectivity between overcurrent protective devices ............................................... 37

535.1.1 General ......................................................................................................... 37

535.1.2 Partial selectivity ........................................................................................... 38

535.1.3 Full selectivity ................................................................................................ 38

535.1.4 Total selectivity .............................................................................................. 38

535.1.5 Enhanced selectivity ...................................................................................... 38

535.2 Co-ordination between residual current protective devices and OCPDs................. 39

535.3 Selectivity between residual current protective devices ......................................... 39

535.4 Selectivity of RCD and OCPD ............................................................................... 39

535.5 Combined short-circuit protection of OCPDs ......................................................... 39

536 Isolation and switching .................................................................................................. 40

536.2 Isolation ................................................................................................................ 40

536.2.1 General ......................................................................................................... 40

536.2.2 Devices for isolation ...................................................................................... 41

536.3 Switching-off for mechanical maintenance ............................................................ 42

536.3.1 General ......................................................................................................... 42

536.3.2 Devices for switching-off for mechanical maintenance ................................... 42

536.4 Emergency switching ............................................................................................ 43

536.4.1 General ......................................................................................................... 43

536.4.2 Devices for emergency switching-off .............................................................. 43

536.4.3 Devices for emergency stopping .................................................................... 44

536.5 Functional switching (control) ................................................................................ 44

536.5.1 General ......................................................................................................... 44

536.5.2 Devices for functional switching ..................................................................... 44

537 Monitoring ..................................................................................................................... 45

537.1 General ................................................................................................................. 45

537.1.1 Monitoring devices ......................................................................................... 45

537.1.2 Selection of insulation monitoring devices (IMDs) .......................................... 45

537.1.3 Selection of residual current monitoring devices (RCMs) ............................... 45

537.2 IT systems for continuity of supply ........................................................................ 45

537.2.1 General ......................................................................................................... 45

537.2.2 Insulation monitoring devices (IMDs) ............................................................. 46

537.2.3 Installation of IMDs ........................................................................................ 46

537.3 IT public distribution system .................................................................................. 46

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– 4 – IEC 60364-5-53:2019 © IEC 2019

537.4 Off-line systems in TN, TT and IT systems ............................................................ 46

Annex A (informative) Position of devices for overload protection ........................................ 48

A.1 General ................................................................................................................. 48

A.2 Cases where overload protection need not be placed at the origin of the

branch circuit ........................................................................................................ 48

Annex B (informative) Position of devices for short-circuit protection ................................... 50

B.1 General ................................................................................................................. 50

B.2 Cases where short-circuit protection need not be placed at the origin of

branch circuit ........................................................................................................ 50

Annex C (informative) SPD installation – Examples of installation diagrams according

to system configurations ....................................................................................................... 52

C.1 TT system – 3 phase supply plus neutral .............................................................. 52

C.2 TN-C and TN-C-S systems – 3 phase supply ........................................................ 56

C.3 TN-S system – 3 phase supply plus neutral ........................................................... 60

C.4 IT system – 3 phase supply with or without neutral ............................................... 62

Annex D (informative) Installation supplied by overhead lines .............................................. 65

Annex E (normative) Reference standards for devices for isolation and switching ................ 66

Annex F (informative) List of notes concerning certain countries .......................................... 68

Bibliography .......................................................................................................................... 75

Figure 1 – Example of installation of class I, class II and class III tested SPDs ..................... 25

Figure 2 – Connection type CT1 (4+0-configuration) for a three-phase system with

neutral .................................................................................................................................. 26

Figure 3 – Connection type CT1 (3+0-configuration) for a three-phase system ...................... 26

Figure 4 – Connection type CT2 (e.g. 3+1-configuration) for a three-phase system with

neutral .................................................................................................................................. 27

Figure 5 – Connection points of an SPD assembly ................................................................ 31

Figure 6 – Example of overcurrent protection in the SPD branch by using a dedicated

external overcurrent protective device................................................................................... 32

Figure 7 – Protective device, which is a part of the installation, also used to protect the

SPD ...................................................................................................................................... 33

Figure 8 – Connection of the SPD ......................................................................................... 35

Figure 9 – Example of installation of an SPD in order to decrease lead length of SPD

supply conductors ................................................................................................................. 36

Figure 10 – Example of selectivity ......................................................................................... 38

Figure 11 – Example of currents and their correlation to selectivity ....................................... 39

Figure 12 – Example of combined short-circuit protection of OCPDs ..................................... 40

Figure A.1 – Overload protective device (P ) not at the origin of branch circuit (B) ............... 48

Figure A.2 – Overload protective device (P ) installed within 3 m of the origin of the

branch circuit (B) .................................................................................................................. 49

Figure B.1 – Limited change of position of short-circuit protective device (P ) on a

branch circuit ........................................................................................................................ 50

Figure B.2 – Short-circuit protective device P installed at a point on the supply side

of the origin of a branch circuit .............................................................................................. 51

Figure C.1 – Example of SPDA installation with connexion type CT2 on the supply side

(upstream) of the main RCD in TT system............................................................................. 52

Figure C.2 – Example of SPD installation with connexion type CT2 on the supply side

(upstream) of the main RCD in TT system............................................................................. 53

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IEC 60364-5-53:2019 © IEC 2019 – 5 –

Figure C.3 – Example of SPDA installation on the load side (downstream) of the main

RCD in TT system ................................................................................................................. 54

Figure C.4 – Example of SPD installation on the load side (downstream) of the RCD in

TT system ............................................................................................................................. 55

Figure C.5 – Example of SPDA installation in TN-C system .................................................. 56

Figure C.6 – Example of SPD installation with connexion type CT1 in TN-C system .............. 57

Figure C.7 – Example of SPD installation in TN-C-S system where the PEN is

separated into PE and N at the origin of the installation (upstream of the SPD) .................... 58

Figure C.8 – Example of SPDs installation in TN-C-S in different distribution boards ............ 59

Figure C.9 – Example of SPDA installation in TN-S system ................................................... 60

Figure C.10 – Example of SPDs installation in TN-S ............................................................. 61

Figure C.11 – Example of SPDA installation in IT system with neutral ................................... 62

Figure C.12 – Example of SPD installation in IT system without neutral ................................ 63

Figure C.13 – Example of SPD installation in IT system with neutral ..................................... 64

Figure F.1 – Single user ........................................................................................................ 71

Figure F.2 – Several users .................................................................................................... 71

Figure F.3 – Lamp control circuit with switching in the neutral conductor .............................. 73

Table 1 – Required rated impulse voltage of equipment ........................................................ 28

Table 2 – U of the SPD dependent on supply system configuration ..................................... 29

Table 3 – Nominal discharge current (I ) in kA depending on supply system and

connection type .................................................................................................................... 30

Table 4 – Selection of impulse discharge current (I ) where the building is protected

imp

against direct lightning strike ................................................................................................ 30

Table 5 – Connection of the SPD dependent on supply system ............................................. 34

Table D.1 – Selection of impulse discharge current (I ) .................................................... 65

imp

Table E.1 – Devices for isolation and switching..................................................................... 66

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– 6 – IEC 60364-5-53:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW-VOLTAGE ELECTRICAL INSTALLATIONS –
Part 5-53: Selection and erection of electrical equipment – Devices for
protection for safety, isolation, switching, control and monitoring
FOREWORD

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International Standard IEC 60364 has been prepared by IEC technical committee 64:

Electrical installations and
...