HD 60364-5-534:2008

Low-voltage electrical installations - Part 5-53: Selection and erection of electrical equipment - Isolation, switching and control - Clause 534: Devices for protection against overvoltages

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 consolidated version consists of the third edition (2001) and its amendment 1 (2002). Therefore, no need to order amendment in addition to this publication.

Errichten von Niederspannungsanlagen - Teil 5-53: Auswahl und Errichtung elektrischer Betriebsmittel - Trennen, Schalten und Steuern - Abschnitt 534: Überspannungs-Schutzeinrichtungen (SPDs)

Installations électriques à basse tension - Partie 5-53: Choix et mise en oeuvre des matériels électriques - Sectionnement, coupure et commande - Article 534: Dispositifs pour la protection contre les surtensions

Nizkonapetostne električne inštalacije - 5-53. del: Izbira in namestitev električne opreme - Ločevanje, stikanje in krmiljenje - 534. točka: Naprave za prenapetostno zaščito (IEC 60364-5-53:2001/A1:2002, točka 534, spremenjen)

General Information

• Status: Withdrawn
• Publication Date: 28-Aug-2008
• ICS: 29.020 - Electrical engineering in general
• ICS: 29.130 - Switchgear and controlgear
• ICS: 91.140.50 - Electricity supply systems
• Technical Committee: CLC/TC 64 - Electrical installations and protection against electric shock
• Drafting Committee: IEC/TC 64 - IEC_TC_64
• Parallel Committee: IEC/TC 64 - IEC_TC_64
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 29-Aug-2008
• Completion Date: 29-Aug-2008
• Ref Project: SIST HD 60364-5-534:2008 - Low-voltage electrical installations -- Part 5-53: Selection and erection of electrical equipment - Isolation, switching and control -- Clause 534: Devices for protection against overvoltages

Standards Content (Sample)

SLOVENSKI STANDARD
SIST HD 60364-5-534:2008
01-november-2008
1L]NRQDSHWRVWQHHOHNWULþQHLQãWDODFLMHGHO,]ELUDLQQDPHVWLWHYHOHNWULþQH
RSUHPH/RþHYDQMHVWLNDQMHLQNUPLOMHQMHWRþND1DSUDYH]DSUHQDSHWRVWQR
]DãþLWR,(&$WRþNDVSUHPHQMHQ
Electrical installations of buildings - Part 5-53: Selection and erection of electrical
equipment - Isolation, switching and control - Clause 534: Devices for protection against
overvoltages
Errichten von Niederspannungsanlagen - Teil 5-53: Auswahl und Errichtung elektrischer
Betriebsmittel - Trennen, Schalten und Steuern - Abschnitt 534: Überspannung-
Schutzeinrichtungen (ÜSE)
Installations électriques à basse tension - Partie 5-53: Choix et mise en oeuvre des
matériels électriques - Sectionnement, coupure et commande - Article 534: Dispositifs
pour la protection contre les surtensions
Ta slovenski standard je istoveten z: HD 60364-5-534:2008
ICS:
29.120.99 'UXJDHOHNWULþQDGRGDWQD Other electrical accessories
RSUHPD
91.140.50 Sistemi za oskrbo z elektriko Electricity supply systems
SIST HD 60364-5-534:2008 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST HD 60364-5-534:2008

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SIST HD 60364-5-534:2008

HARMONIZATION DOCUMENT
HD 60364-5-534

DOCUMENT D'HARMONISATION
August 2008
HARMONISIERUNGSDOKUMENT

ICS 29.020; 91.140.50


English version


Low-voltage electrical installations -
Part 5-53: Selection and erection of electrical equipment -
Isolation, switching and control -
Clause 534: Devices for protection against overvoltages
(IEC 60364-5-53:2001/A1:2002 (Clause 534), modified)


Installations électriques à basse tension - Errichten von Niederspannungsanlagen -
Partie 5-53: Choix et mise en oeuvre Teil 5-53: Auswahl und Errichtung
des matériels électriques - elektrischer Betriebsmittel -
Sectionnement, coupure et commande - Trennen, Schalten und Steuern -
Article 534: Dispositifs pour la protection Abschnitt 534: Überspannung-
contre les surtensions Schutzeinrichtungen (ÜSE)
(CEI 60364-5-53:2001/A1:2002 (IEC 60364-5-53:2001/A1:2002
(Article 534), modifiée) (Abschnitt 534), modifiziert)




This Harmonization Document was approved by CENELEC on 2008-05-01. 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 Central Secretariat 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, 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: rue de Stassart 35, B - 1050 Brussels


© 2008 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. HD 60364-5-534:2008 E

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SIST HD 60364-5-534:2008
HD 60364-5-534:2008 - 2 -
Foreword
The text of the International Standard IEC 60364-5-53:2001/A1:2002, Clause 534, prepared by
IEC TC 64, Electrical installations and protection against electric shock, together with the common
modifications prepared by SC 64A, Electrical installations and protection against electric shock –
Protection against electric shock, of Technical Committee CENELEC TC 64, Electrical
installations and protection against electric shock, was submitted to the formal vote and was
approved by CENELEC as HD 60364-5-534 on 2008-05-01.
The following dates were fixed:
- latest date by which the existence of the HD
has to be announced at national level (doa) 2008-11-01
- latest date by which the HD has to be implemented
at national level by publication of a harmonized
national standard or by endorsement (dop) 2009-05-01
- latest date by which the national standards conflicting
with the HD have to be withdrawn (dow) 2011-05-01
In this document, the common modifications are indicated by a vertical line at the left margin of
the text.
_________________

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SIST HD 60364-5-534:2008
- 3 - HD 60364-5-534:2008

530.2 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.
NOTE Where an international publication has been modified by common modifications, indicated by (mod), the
relevant EN/HD applies.

IEC 60364-4-41 - Low voltage electrical installations - HD 60364-4-41 -
(mod) Part 4-41: Protection for safety - Protection
against electric shock

1)
IEC 60364-4-44 - Electrical installations of buildings - HD 60364-4-443 -
Part 4-44: Protection for safety - Protection
against voltage disturbances and
electromagnetic disturbances

IEC 60364-6 - Low voltage electrical installations - HD 60364-6 -
(mod) Part 6: Verification

IEC 60664-1 - Insulation coordination for equipment within EN 60664-1 -
low-voltage systems -
Part 1: Principles, requirements and tests

IEC 62305-4 - Protection against lightning - EN 62305-4 -
Part 4: Electrical and electronic systems
within structures

IEC 61643-11 - Low-voltage surge protective devices - EN 61643-11 -
(mod) Part 11: Surge protective devices connected
to low-voltage power systems -
Requirements and tests

IEC 61643-12 - Low-voltage surge protective devices - CLC/TS 61643-12 -
(mod) Part 12: Surge protective devices connected
to low-voltage power distribution systems -
Selection and application principles


1)
HD 60364-4-443:2006 is based on IEC 60364-4-44:2001/A1:2003 (modified), Clause 443: Protection against
overvoltages of atmospheric origin or due to switching.

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SIST HD 60364-5-534:2008
HD 60364-5-534:2008 - 4 -
534 Devices for protection against overvoltages
534.1 General
This clause contains provisions for the application of voltage limitation to obtain an insulation
coordination in the cases described in HD 60364-4-443, EN 60664-1, EN 62305-4 and
CLC/TS 61643-12.
SPDs, specific isolating transformers, filters or a combination of these may be used for protection
against overvoltages.
This clause gives the requirements for the selection and erection of
– surge protective devices (SPDs) for electrical installations of buildings to obtain a limitation of
transient overvoltages of atmospheric origin transmitted via the supply distribution system and
against switching overvoltages;
– SPDs for the protection against transient overvoltages caused by direct lightning strokes or
lightning strokes in the vicinity of buildings, protected by a lightning protection system.
This clause does not take into account surge protective components which may be incorporated in
the appliances connected to the installation. The presence of such components may modify the
behaviour of the main surge protective device of the installation and may need an additional
coordination.
This clause also covers protection against overcurrent and consequences in case of SPD failure.
This clause applies to a.c. power circuits.
For d.c. power circuits, the requirements in this clause may be applied as far as is useful.
For special applications, other or additional requirements may be necessary as specified in the
relevant Part 7 of HD 60364.
534.2 Selection and erection of SPDs in building installations
534.2.1 Use of SPDs
HD 60364-4-443 deals with protection against overvoltages of atmospheric origin (caused by
indirect, distant lightning strokes) and switching overvoltages. This protection is normally provided
by the installation of Type 2 SPDs and if necessary Type 3 SPDs.
When required in accordance with HD 60364-4-443 or otherwise specified, SPDs shall be installed
near the origin of the installation or in the main distribution assembly, closest to the origin of the
installation inside the building.
EN 62305-4 and CLC/TS 61643-12 deal with the protection against the effects of direct lightning
strokes or strokes near to the supply system. Both documents describe the selection and the
application of SPDs according to the Lightning Protection Zones (LPZ) concept. The LPZ concept
describes the installation of Type 1, Type 2 and Type 3 SPDs (see Annex D).
When required in accordance with EN 62305-4 or otherwise specified, SPDs shall be installed at
the origin of the installation.
Additional SPDs may be necessary to protect sensitive equipment. Such SPDs shall be
coordinated with the SPDs installed upstream (see 534.2.3.6) and they should be installed as
close as practicable to the equipment to be protected.

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SIST HD 60364-5-534:2008
- 5 - HD 60364-5-534:2008

In the case where SPDs are part of the fixed electrical installation, but not mounted inside a
distribution board (e.g. in a socket outlet), their presence shall be indicated by a label in the
relevant distribution board, indicating precisely their location as near as is reasonably possible to
the origin of the circuit under consideration.
Special precautions should be taken in locations where the external influence BE2 exists.
Appropriate information shall be provided by the SPD manufacturer.
An example how to install SPDs is shown in Annex D.
NOTE  Where SPDs are required on the power system consideration should be given regarding the installation of
SPDs on other incoming networks (such as telecommunication and signalling services).
534.2.2 Connection of SPDs
Surge protective devices shall be connected at least between the following points (see Annexes A,
B and C):
a) in installations where there is a direct connection between the neutral conductor and the PE
at or near the installation point of the SPDs or if there is no neutral conductor between each
line conductor and either the main earthing terminal or the main protective conductor,
whichever is the shortest route - connection Type A;
b) in installations where there is no direct connection between the neutral conductor and the PE
at or near the installation point of the SPDs, then either
between each line conductor and either the main earthing terminal or the main protective
conductor, and between the neutral conductor and either the main earthing terminal or
the protective conductor, whichever is the shortest route - connection Type B;
or
between each line conductor and the neutral conductor and between the neutral
conductor and either the main earthing terminal or the protective conductor, whichever
route is shorter - connection Type C .
NOTE 1 The impedance connecting the neutral to the PE in IT systems is not considered as a connection.
NOTE 2 If a line conductor is earthed, it is considered to be equivalent to a neutral conductor for the application of
this subclause.
NOTE 3 For all connection types connection of the relevant SPD(s) to the main earthing terminal and to the main
protective conductor may improve the protection level.
Where required according to 534.2.1, SPDs at or near the origin of the installation shall be connected
according to Table 53B (typical examples are shown in Annexes A to C)
Additional SPDs at other locations should preferably be installed according to Table 53B, but other
modes of protection may be used.

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SIST HD 60364-5-534:2008
HD 60364-5-534:2008 - 6 -
Table 53B - Installation of surge protective devices dependent on connection type
SPDs connected Connection Type A Connection Type B Connection Type C
between (Examples: (Example: (Example:
see Annex A, Figure A.1 see Annex B, Figure B.1) see Annex B, Figure B.2)
and Annex C, Figure C.1)
Each line conductor and Not applicable Not applicable Required
neutral conductor
Each line conductor and Required Not applicable Not applicable
PEN conductor
Each line conductor and Not applicable Required Not applicable
PE conductor
Neutral conductor and Not applicable Required Required
PE conductor
Line conductors Optional Optional Optional

534.2.3 Selection of surge protective devices (SPDs)
The SPDs shall comply with EN 61643-11 and EN 61643-11/A11.
NOTE  Additional information regarding selection and application is given in CLC/TS 61643-12.
534.2.3.1 Selection with regard to protection level (U )
p
If HD 60364-4-443 requires SPDs, the protection level U of SPDs shall be selected in accordance
p
with impulse withstand voltage category II of Table 1 in HD 60364-4-443.
If EN 62305-4 requires SPDs for the protection against overvoltages caused by direct lightning
strokes, the protection level U of these SPDs shall also be selected in accordance with impulse
p
withstand voltage category II of Table 1 in HD 60364-4-443.
For example in 230/400 V installations, the protection level U shall not exceed 2,5 kV.
p
When connection Type C according to 534.2.2 is used, the protection level required shall be met
by the serial combination of the two SPDs between line and neutral and between neutral and PE.
When the protection level required cannot be reached with a single set of SPDs, additional SPDs
which are coordinated shall be applied to ensure the required protection level.
NOTE  Additional SPDs selected in accordance with impulse withstand voltage category I of Table 1 in HD 60364-4-443
may be necessary to protect sensitive equipment.
534.2.3.2 Selection with regard to continuous operating voltage (U )
c
The maximum continuous operating voltage U of SPDs shall be equal to or higher than shown in
c
the following Table 53C.

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SIST HD 60364-5-534:2008
- 7 - HD 60364-5-534:2008

Table 53C - Minimum required U of the SPD dependent on system configuration
c
SPD connected System configuration of distribution network
between
TN system TT system IT with distributed neutral IT without
distributed neutral


Line conductor 1,1 U 1,1 U 1,1 U NA
o o o
and neutral conductor
Line conductor and PE conductor 1,1 U 1,1 U U 1,1 x U
o o
a a a
Neutral conductor NA
U U U
o o o
and PE conductor
Line conductor and PEN conductor 1,1 U NA NA NA
o
Line conductors 1,1 U 1,1 U 1,1 U 1,1 U
NA: not applicable.
NOTE 1  U is the line-to-neutral voltage of the low-voltage system.
o
NOTE 2  U is the line-to-line voltage of the low-voltage system.

NOTE 3  This table is based on EN 61643-11.

a
These values are related to worst case fault conditions, therefore the tolerance of 10 % is not taken into account.

534.2.3.3 Selection with regard to temporary overvoltages (TOVs)
SPDs developed in accordance with EN 61643-11 and EN 61643-11/A11 and installed according to
the manufacturers installation instructions are designed to behave in an acceptable manner when
subject to the TOV stresses expected.
NOTE  The loss of neutral is not covered by these requirements. Though there is currently no specific test in
EN 61643-11, SPDs are expected to fail safely.
534.2.3.4 Selection with regard to discharge current (I ) and impulse current (I )
n imp
If HD 60364-4-443 requires SPDs, the nominal discharge current I shall not be less than 5 kA
n
8/20 for each mode of protection.
NOTE  Any SPDs protective component may be connected line-to-line or line-to-earth or line-to neutral or neutral-to-
earth and combinations thereof. These paths are referred to as modes of protection (EN 61643-11).
In case of installation according to 534.2.2 connection Type C, the nominal discharge current I
n
for the surge protective device connected between the neutral conductor and the PE shall not be
less than 20 kA 8/20 for three-phase systems and 10 kA 8/20 for single-phase systems.
If EN 62305-4 requires SPDs, the lightning impulse current I according to EN 61643-11 shall be
imp
calculated according to EN 62305-4. Further information is given in CLC/TS 61643-12. If the
current value cannot be established, the value of I shall not be less than 12,5 kA for each mode
imp
of protection.
In case of an installation according to 534.2.2 connection Type C, the lightning impulse current I
imp
for the surge protective device connected between the neutral conductor and the PE shall be
calculated similarly to the above mentioned standards. If the current value cannot be established
the value of I shall not be less than 50 kA for three-phase systems and 25 kA for single-phase
imp
systems.
When a single SPD is used for protection
...

SLOVENSKI oSIST prHD 60364-5-534:2005

PREDSTANDARD
september 2005
Električne inštalacije zgradb – 5-53. del: Izbira in namestitev električne
opreme – Ločevanje, stikanje in krmiljenje – 534. točka: Naprave za
prenapetostno zaščito
Electrical installations of buildings – Part 5-53: Selection and erection of electrical
equipment – Isolation, switching and control – Clause 534: Devices for protection
against overvoltages
ICS 29.120.99; 91.140.50 Referenčna številka
oSIST prHD 60364-5-534:2005(en)
©  Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno

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DRAFT
HARMONIZATION DOCUMENT prHD 60364-5-534
DOCUMENT D'HARMONISATION
HARMONISIERUNGSDOKUMENT June 2005

ICS 29.130; 91.140.50


English version


Electrical installations of buildings
Part 5-53: Selection and erection of electrical equipment -
Isolation, switching and control
Clause 534: Devices for protection against overvoltages
(IEC 60364-5-53:2001/A1:2002, modified)

Installations électriques des bâtiments Elektrische Anlagen von Gebäuden
Partie 5-53: Choix et mise en oeuvre des Teil 5-53: Auswahl und Errichtung
matériels électriques - elektrischer Betriebsmittel -
Sectionnement, coupure et commande Trennen, Schalten und Steuern -
Article 534: Dispositifs pour la protection Abschnitt 534: Überspannung-
contre les surtensions Schutzeinrichtungen (ÜSE)
(CEI 60364-5-53:2001/A1:2002, modifiée) (IEC 60364-5-53:2001/A1:2002,
modifiziert)

This draft Harmonization Document is submitted to CENELEC members for CENELEC enquiry.
Deadline for CENELEC: 2005-12-09

The text of this draft consists of the text of IEC 60364-5-53:2001/A1:2002 with common modifications
prepared by SC 64A of Technical Committee 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, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden,
Switzerland and United Kingdom.

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

Central Secretariat: rue de Stassart 35, B - 1050 Brussels


© 2005 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Project: 15988 Ref. No. prHD 60364-5-534:2005 E
Draft for Enquiry

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prHD 60364-5-534:2005 - 2 -
Foreword
The text of International Standard IEC 60364-5-53:2001/A1:2002 prepared by IEC TC 64,
Electrical installations and protection against electric shock, together with the common
modifications prepared by CENELEC SC 64A, Protection against electric shock, of Technical
Committee CENELEC TC 64, Electrical installations of buildings, is submitted to the CENELEC
enquiry.


In this document, the common modifications are indicated by a vertical line at the left margin of
the text.

_____________


Draft for Enquiry

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- 3 - prHD 60364-5-534:2005

Text of prHD 60364-5-534

530.2 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.
NOTE Where an international publication has been modified by common modifications, indicated by (mod), the
relevant EN/HD applies.

IEC 60364-4-41 2001 Electrical installations of buildings - -
Part 4-41: Protection for safety -
Protection against elctric shock



IEC 60364-4-44 2001 Part 4-44: Protection for safety - - -
Protection against voltage disturbances
and electromagnetic disturbances

IEC 60364-6-61 2001 Part 6-61: Verification - Initial verification- -


1)
IEC 60664-1 1992 Insulation coordination for equipment 2003
EN 60664-1
within low-voltage systems
Part 1: Principles, requirements and tests



IEC 61312-1 1995 Protection against lightning - -
electromagnetic impulse
Part 1: General principles

IEC/TS 61312-2 1999 Part 2: Shielding of structures, bonding - -
inside structures and earthing

IEC/TS 61312-3 2000 Part 3: Requirements of surge protective - -
devices (SPDs)

IEC 61643-1 1998 Low-voltage surge protective devices EN 61643-11 2002
(mod) Part 11: Surge protective devices
+ corr. November 1998 connected to low-voltage power systems
A1 2001 - Requirements and tests - -
+ A11 2005



IEC 61643-12 2002 Part 12: Surge protective devices - -
connected to low-voltage power
distribution systems - Selection and
application principles


1)
EN 60664-1:2003 includes A1:2000 + A2:2002 to IEC 60664-1:1992.

Draft for Enquiry

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prHD 60364-5-534:2005 - 4 -
534 Devices for protection against overvoltages
534.1 General
This clause contains provisions for the application of voltage limitation to obtain an insulation
coordination in the cases described in IEC 60364-4-44, IEC 60664-1, IEC/TS 61312-2 and
IEC 61643-12.
SPDs, specific isolating transformers, filters or a combination of these may be used for protection
against overvoltages.
This clause gives the requirements for the selection and erection of
– surge protective devices (SPDs) for electrical installations of buildings to obtain a limitation of
transient overvoltages of atmospheric origin transmitted via the supply distribution system and
against switching overvoltages;
– SPDs for the protection against transient overvoltages caused by direct lightning strokes or
lightning strokes in the vicinity of buildings, protected by a lightning protection system.
This clause does not take into account surge protective components which may be incorporated in
the appliances connected to the installation. The presence of such components may modify the
behaviour of the main surge protective device of the installation and may need an additional
coordination.
This clause applies to a.c. power circuits.
For d.c. power circuits, the requirements in this clause may be applied as far as is useful.
For special applications, other or additional requirements may be necessary in the relevant Part 7
of IEC 60364.
534.2 Selection and erection of SPDs in building installations
534.2.1 Use of SPDs
IEC 60364-4-44, Clause 443, includes protection against overvoltages of atmospheric origin
(caused by indirect, distant lightning strokes) and switching overvoltages. This protection is
normally provided by the installation of type 2 SPDs and if necessary type 3 SPDs.
When required in accordance with IEC 60364-4-44 or otherwise specified, SPDs shall be installed
near the origin of the installation or in the main distribution assembly, closest to the origin of the
installation inside the building.
IEC 61312-1 includes protection against the effects of direct lightning strokes or strokes near to
the supply system. IEC/TS 61312-3 describes the correct selection and application of SPDs
according to the Lightning Protection Zones (LPZ) concept. The LPZ concept describes the
installation of type 1, type 2 and type 3 SPDs.
When required in accordance with IEC 61312-1 or otherwise specified, SPDs shall be installed at
the origin of the installation.
Additional SPDs may be necessary to protect sensitive equipment. Such SPDs shall be
coordinated with the SPDs installed upstream (see 534.2.3.6).


Draft for Enquiry

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- 5 - prHD 60364-5-534:2005

In the case where SPDs are part of the fixed electrical installation, but not mounted inside a
distribution board (e.g. in a socket outlet), their presence shall be indicated by a label on or as
near as is reasonably possible to the origin of the circuit under consideration.
Special precautions should be taken in case of BE2 locations.
534.2.2 Connection of SPDs
Surge protective devices shall be connected at least between the following points (see Annexes A,
B and C):
PE at or near the installation point of the SPDs or if there is no neutral conductor:a) In TN-
and TT-systems if there is a direct connection between the neutral conductor and the
between each line conductor and either the main earthing terminal or the main protective
conductor, whichever is the shortest route – connection type A;
b) In TN- and TT- and IT-systems where there is no direct connection between the neutral
conductor and the PE at or near the installation point of the SPDs, then either
between each line conductor and either the main earthing terminal or the main protective
conductor, and between the neutral conductor and either the main earthing terminal or the
protective conductor, whichever is the shortest route – connection type B;
or
between each line conductor and the neutral conductor and between the neutral conductor and
either the main earthing terminal or the protective conductor, whichever route is shorter –
connection type C .
NOTE 1  The impedance connecting the neutral to the PE in IT systems is not considered as a connection
NOTE 2  If a line conductor is earthed, it is considered to be equivalent to a neutral conductor for the application of
this subclause.
SPDs at or near the origin of the installation are, in general, installed as shown in Annexes A to
C and according to Table 53B:
Table 53B – Installation of surge protective devices dependent on connection type
SPDs Connection type A Connection type B Connection type C
connected
between
Each line conductor and NA NA •
neutral conductor
Each line conductor and • • NA
PE(N) conductor
Neutral conductor and PE NA • •
conductor
Line conductors + + +
• mandatory
NA not applicable
+ optional, in addition

In addition the connection type and the system (TN-, TT- and/or IT-system) as well as the correct
connection between conductors (L-N, L-PE, N-PE, and/or L-L) shall comply with the
manufacturers installation instructions.


Draft for Enquiry

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prHD 60364-5-534:2005 - 6 -

534.2.3 Selection of surge protective devices (SPDs)
The SPDs shall comply with EN 61643-11 and EN 61643-11/A11. Additional information regarding
selection and application is given in IEC 61643-12.
534.2.3.1 Selection with regard to protection level (U )
p
If Clause 443 of IEC 60364-4-44 requires SPDs, the protection level U of SPDs shall be selected in
p
accordance with impulse withstand voltage category II of Table 44B in IEC 60364-4-44.
If IEC 61312-1 requires SPDs for the protection against overvoltages caused by direct lightning
strokes, the protection level of these SPDs shall also be selected in accordance with impulse
withstand voltage category II of Table 44B in IEC 60364-4-44.
For example in 230/400 V installations, the protection level U shall not exceed 2,5 kV.
p
When connection type C according to 534.2.2 is used, the above requirements also apply to the
total protection level between line conductors and PE.
When the required protection level cannot be reached with a single set of SPDs, additional,
coordinated SPDs shall be applied to ensure the required protection level.
534.2.3.2 Selection with regard to continuous operating voltage (U )
c
The maximum continuous operating voltage U of SPDs shall be equal to or higher than shown in
c
the following Table 53C.
Table 53C – Minimum required U of the SPD dependent on system configuration
c
System configuration of distribution network
SPD connected
TN- or TT-system IT with distributed neutral IT without
between
distributed neutral
Line conductor 1,1 U 1,1 U NA
o o
and neutral conductor
a
Line conductor and PE conductor 1,1 U
o
a U
3 U
o
a a
Neutral conductor NA
U U
o o
and PE conductor
Line conductor and PEN conductor 1,1 U NA NA
o
Line conductors 1,1 U 1,1 U 1,1 U
NA: not applicable
NOTE 1  U is the line-to-neutral voltage of the low-voltage system.
o
NOTE 2  U is the line-to-line voltage of the low-voltage system.

NOTE 3  This table is based on EN 61643-11.
a
These values are related to worst case fault conditions, therefore the tolerance of 10 % is not taken into account.




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534.2.3.3 Selection with regard to temporary overvoltages (TOVs)
SPDs shall comply with EN 61643-11 and EN 61643-11/A11.


NOTE 1  SPDs developed in accordance with the above standard and installed according to the manufacturers
installation instructions are designed to behave in an acceptable manor when subject to the TOV stresses expected.
NOTE 2  The loss of neutral is not covered by these requirements. Though there is currently no specific test in
EN 61643-11, SPDs are expected to fail safely.

534.2.3.4 Selection with regard to discharge current (I ) and impulse current (I )
n imp
If IEC 60364-4-44 Clause 443 requires SPDs, the nominal discharge current I shall not be less
n
than 5 kA 8/20 for each mode of protection.
NOTE  An SPDs protective components may be connected line-to-line or line-to-earth or line-to neutral or neutral-to-
earth and combinations thereof. These paths are referred to as modes of protection (EN 61643-11).
In case of installation according to 534.2.2 connection type C, the nominal discharge current I for
n
the surge protective device connected between the neutral conductor and the PE shall not be less
than 20 kA 8/20 for three-
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