SIST HD 60364-7-712:2016
(Main)Low-voltage electrical installations - Part 7-712: Requirements for special installations or locations - Photovoltaic (PV) systems
Low-voltage electrical installations - Part 7-712: Requirements for special installations or locations - Photovoltaic (PV) systems
This section applies to the electrical installation of PV generator intended to supply all or part of an
installation and feeding of electricity into the public grid or local distribution.
In this section, the electrical equipment of a PV generator, like any other item of electrical equipment,
is dealt with only so far as its selection and application in the installation is concerned.
The electrical installation of a PV generator starts from a PV module or a set of PV modules
connected in series with their cables, provided by the PV module manufacturer, up to the user
installation or the utility supply point.
Requirements of this document apply to
– PV generators for supply to an installation which is not connected to a system for distribution of
electricity to the public,
– PV generators for supply to an installation in parallel with a system for distribution of electricity to
the public,
– PV generators for supply to an installation as an alternative to a system for distribution of
electricity to the public,
– appropriate combination of the above.
Requirements for PV generators with batteries or other energy storage methods are under
consideration.
Errichten von Niederspannungsanlagen - Teil 7-712: Anforderungen für Betriebsstätten, Räume und Anlagen besonderer Art - Photovoltaik-(PV)-Stromversorgungssysteme
Installations électriques basses tensions - Partie 7-712: Exigences pour les installations et emplacements spéciaux – Systèmes photovoltaïques (PV)
Nizkonapetostne električne inštalacije - 7-712. del: Zahteve za posebne inštalacije ali lokacije - Fotonapetostni (PV) sistemi
Ta razdelek se uporablja za električno inštalacijo fotonapetostnega generatorja za napajanje celotne napeljave (ali njenega dela)
in prenos elektrike v javno omrežje ali lokalno distribucijo.
V tem razdelku je električna oprema fotonapetostnega generatorja (kot kateri koli drugi del električne opreme)
zajeta le toliko, kolikor je to povezano z njeno izbiro in uporabo v inštalaciji.
Električna inštalacija fotonapetostnega generatorja se začne pri fotonapetostnem modulu ali naboru zaporednih fotonapetostnih modulov s kabli, ki ga/jih zagotovi proizvajalec fotonapetostnih modulov, vse do uporabniške inštalacije ali točke oskrbe z napajanjem.
Zahteve tega dokumenta se uporabljajo za:
– fotonapetostne generatorje za napajanje inštalacije, ki ni povezana s sistemom za distribucijo električne energije v javnih omrežjih;
– fotonapetostne generatorje za napajanje inštalacije, vzporedno povezane s sistemom za distribucijo električne energije v javnih omrežjih;
– fotonapetostne generatorje za napajanje inštalacije kot alternative sistemu za distribucijo električne energije v javnih omrežjih;
– ustrezno kombinacijo zgoraj omenjenih možnosti.
Upoštevajo se zahteve za fotonapetostne generatorje z baterijami ali drugimi viri shranjevanja energije.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST HD 60364-7-712:2016
01-junij-2016
1DGRPHãþD
SIST HD 60364-7-712:2005
1L]NRQDSHWRVWQHHOHNWULþQHLQãWDODFLMHGHO =DKWHYH]DSRVHEQHLQãWDODFLMH
DOLORNDFLMH)RWRQDSHWRVWQL 39 VLVWHPL
Low-voltage electrical installations - Part 7-712: Requirements for special installations or
locations - Photovoltaic (PV) systems
Errichten von Niederspannungsanlagen - Teil 7-712: Anforderungen für Betriebsstätten,
Räume und Anlagen besonderer Art - Photovoltaik-(PV)-Stromversorgungssysteme
Installations électriques basses tensions - Partie 7-712: Exigences pour les installations
et emplacements spéciaux – Systèmes photovoltaïques (PV)
Ta slovenski standard je istoveten z: HD 60364-7-712:2016
ICS:
27.160 6RQþQDHQHUJLMD Solar energy engineering
91.140.50 Sistemi za oskrbo z elektriko Electricity supply systems
SIST HD 60364-7-712:2016 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST HD 60364-7-712:2016
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SIST HD 60364-7-712:2016
HARMONIZATION DOCUMENT HD 60364-7-712
DOCUMENT D'HARMONISATION
HARMONISIERUNGSDOKUMENT
April 2016
ICS 27.160; 91.140.50 Supersedes HD 60364-7-712:2005
English Version
Low-voltage electrical installations -
Part 7-712: Requirements for special installations or locations -
Photovoltaic (PV) systems
Installations électriques basses tensions - Errichten von Niederspannungsanlagen -
Partie 7-712: Exigences pour les installations et Teil 7-712: Anforderungen für Betriebsstätten, Räume
emplacements spéciaux - und Anlagen besonderer Art -
Systèmes photovoltaïques (PV) Photovoltaik-(PV)-Stromversorgungssysteme
This Harmonization Document was approved by CENELEC on 2015-07-27. 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.
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
© 2016 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. HD 60364-7-712:2016 E
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Contents Page
European foreword .4
Introduction .5
712 Photovoltaic systems (PV generator) .6
712.1 Scope .6
712.2 Normative references .6
712.3 Terms and definitions .8
712.4 Protection for safety . 10
712.41 Protection against electric shock . 10
712.410 Introduction . 10
712.412 Protective measure: double or reinforced insulation . 10
712.414 Protective measure: extra-low-voltage provided by SELV and PELV . 10
712.42 Protection against thermal effects . 10
712.421 Protection against fire caused by electrical equipment . 11
712.43 Protection against overcurrent . 11
712.431 Requirements according to the nature of the circuits . 11
712.432 Nature of protective devices . 12
712.433 Protection against overload current . 12
712.434 Protection against short-circuit currents. 13
712.44 Protection against voltage disturbances and electromagnetic disturbances . 13
712.443 Protection against overvoltages of atmospheric origin or due to switching . 13
712.5 Selection and erection of electrical equipment . 14
712.51 Common rules . 14
712.511 Compliance with standards . 14
712.512 Operational conditions and external influences . 14
712.513 Accessibility . 15
712.514 Identification . 15
712.52 Wiring systems . 16
712.521 Types of wiring systems . 16
712.523 Current-carrying capacities . 16
712.525 Voltage drop in consumers installations . 16
712.526 Electrical connections . 16
712.53 Protection, isolation, switching, control and monitoring . 16
712.531 Devices for fault protection by automatic disconnection of supply . 16
712.532 Devices for protection against the risk of fire . 17
712.533 Devices for protection against overcurrent . 17
712.534 Devices for protection against overvoltages . 17
712.537 Isolation and switching . 19
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712.54 Earthing arrangements and protective conductors . 20
712.542 Earthing arrangements . 20
712.6 Verification . 21
Annex A (informative) Example for a single or parallel connected multi-string PV array . 22
Annex B (normative) Calculation of U and I . 23
OC MAX SC MAX
B.1 Calculation of U . 23
OC MAX
B.2 Calculation of I . 24
SC MAX
Annex C (informative) Examples for installation of SPDs for different cases . 25
Annex D (normative) Special national conditions . 26
Bibliography . 27
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European foreword
This document (HD 60364-7-712:2016) has been prepared by CLC/TC 64 "Electrical installations and
protection against electric shock".
The following dates are fixed:
• latest date by which the document has to be implemented at (dop) 2016-10-08
national level by publication of an identical national
standard or by endorsement
(dow) 2019-04-08
• latest date by which the national standards conflicting with
the document have to be withdrawn
This document supersedes HD 60364-7-712:2005 + corrigendum April 2006.
HD 60364-7-712:2016 includes the following significant technical changes with respect to
HD 60364-7-712:2005:
– the scope has been amended to provide explanation for which PV supply systems this
Harmonization Document is suitable;
– terms and definitions are updated to the used wording for the technical definitions of PV-Systems;
– safety related requirements are brought in line with the latest editions of Harmonization
Documents from the HD 60364-4 series, especially on the protection for safety
HD 384.4/HD 60364-4. The respective structure has been adopted;
– calculation principles for the selection of protective devices are provided and brought in line with
the product standards for PV modules;
– where HD 60364-4-443 is not appropriate, a method for a risk assessment is introduced;
– to ensure safety of the various operators (maintenance personnel, inspectors, public distribution
network operators, emergency aid services, etc.), a warning symbol to indicate the presence of a
photovoltaic installation on a building was introduced;
– particular usage of overvoltage devices and their selection is explained;
– Annex B provides calculation methods for U and I .
OC MAX SC MAX
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.
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Introduction
For the purpose of this part, the requirements of HD 60364/HD 384 apply.
The Parts 7XX of HD 60364 contain particular requirements for special installations or locations which
are based on the requirements of the general parts of HD 60364 (Part 1, Part 4, Part 5 and Part 6).
These Parts 7XX have to be considered in conjunction with the requirements of the general parts.
The particular requirements of this part of HD 60364 supplement, modify or replace certain of the
requirements of the general parts of HD 60364 being valid at the time of publication of this part.
The absence of reference to the exclusion of a part or a clause of a general part means that the
corresponding clauses of the general part are applicable (undated reference).
Requirements of other Parts 7XX being relevant for installations covered by this part also apply. This
part may therefore also supplement, modify or replace certain of these requirements valid at the time
of publication of this part.
The clause numbering of this part follows the pattern and corresponding references of HD 60364. The
numbers following the particular number of this part are those of the corresponding parts, or clauses of
HD 60364 being valid at the time of publication of this part as indicated in the normative references of
this document (dated reference).
If additional requirements or explanations are needed which have no direct relation to general parts or
other Parts 7XX the numbering of such clauses are stated as 712.101, 712.102, 712.103 etc.
NOTE In the case where new or amended general parts with modified numbering were published after this
part was issued, the clause numbers referring to a general part in this Part 712 may no longer align with the latest
edition of the general part. Dated references should be observed.
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712 Photovoltaic systems (PV generator)
712.1 Scope
This section applies to the electrical installation of PV generator intended to supply all or part of an
installation and feeding of electricity into the public grid or local distribution.
In this section, the electrical equipment of a PV generator, like any other item of electrical equipment,
is dealt with only so far as its selection and application in the installation is concerned.
The electrical installation of a PV generator starts from a PV module or a set of PV modules
connected in series with their cables, provided by the PV module manufacturer, up to the user
installation or the utility supply point.
Requirements of this document apply to
– PV generators for supply to an installation which is not connected to a system for distribution of
electricity to the public,
– PV generators for supply to an installation in parallel with a system for distribution of electricity to
the public,
– PV generators for supply to an installation as an alternative to a system for distribution of
electricity to the public,
– appropriate combination of the above.
Requirements for PV generators with batteries or other energy storage methods are under
consideration.
712.2 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.
CLC/TS 50539-12, Low-voltage surge protective devices – Surge protective devices for specific
application including d.c. – Part 12: Selection and application principles – SPDs connected to
photovoltaic installations
EN 50521, Connectors for photovoltaic systems – Safety requirements and tests
EN 50539-11, Low-voltage surge protective devices – Surge protective devices for specific application
including d.c. – Part 11: Requirements and tests for SPDs in photovoltaic applications
EN 50618, Electric cables for photovoltaic systems
EN 60269-6, Low-voltage fuses – Part 6: Supplementary requirements for fuse-links for the protection
of solar photovoltaic energy systems (IEC 60269-6)
EN 60529, Degrees of protection provided by enclosures (IP Code) (IEC 60529)
EN 60670 series, Boxes and enclosures for electrical accessories for household and similar fixed
electrical installations (IEC 60670 series)
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 60947-2, Low-voltage switchgear and controlgear – Part 2: Circuit-breakers (IEC 60947-2)
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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 61439 series, Low-voltage switchgear and controlgear assemblies (IEC 61439 series)
EN 61557-8, Electrical safety in low voltage distribution systems up to 1 000 V a.c. and 1 500 V d.c. –
Equipment for testing, measuring or monitoring of protective measures – Part 8: Insulation monitoring
devices for IT systems (IEC 61557-8)
EN 61643-11, Low-voltage surge protective devices – Part 11: Surge protective devices connected to
low-voltage power systems – Requirements and test methods (IEC 61643-11)
EN 61730-1:2007, Photovoltaic (PV) module safety qualification – Part 1: Requirements for
construction (IEC 61730-1:2004, mod.)
EN 62109-1:2010, Safety of power converters for use in photovoltaic power systems – Part 1: General
requirements (IEC 62109-1:2010)
EN 62109-2:2011, Safety of power converters for use in photovoltaic power systems – Part 2:
Particular requirements for inverters (IEC 62109-2:2011)
EN 62262, Degrees of protection provided by enclosures for electrical equipment against external
mechanical impacts (IK code) (IEC 62262)
EN 62305-2:2012, Protection against lightning – Part 2: Risk management (IEC 62305-2:2010, mod.)
EN 62305-3:2011, Protection against lightning – Part 3: Physical damage to structures and life hazard
(IEC 62305-3:2010, mod.)
EN 62305-4:2011, Protection against lightning – Part 4: Electrical and electronic systems within
structures (IEC 62305-4:2010, mod.)
EN 62423:2012, Type F and type B residual current operated circuit-breakers with and without integral
overcurrent protection for household and similar uses (IEC 62423:2009, mod. + corr. Dec. 2011)
EN 62446:2009, Grid connected photovoltaic systems – Minimum requirements for system
documentation, commissioning tests and inspection (IEC 62446:2009)
EN 62852, Connectors for DC-application in photovoltaic systems – Safety requirements and tests
(IEC 62852)
HD 384 / HD 60364 series, Low-voltage electrical installations (IEC 60364 series)
HD 60364-4-41:2007 + corr. July 2007, Low-voltage electrical installations – Part 4-41: Protection for
safety – Protection against electric shock (IEC 60364-4-41:2005, mod.)
HD 60364-4-443:2016, Low-voltage electrical installations – Part 4-44: Protection for safety –
Protection against voltage disturbances and electromagnetic disturbances – Clause 443: Protection
against transient overvoltages of atmospheric origin or due to switching
(IEC 60364-4-44:2007/A1:2015, mod.)
HD 60364-5-551:2010 + corr. Dec. 2010, Low-voltage electrical installations – Part 5-55: Selection
and erection of electrical equipment – Other equipment – Clause 551: Low-voltage generating sets
(IEC 60364-5-55:2001/A2:2008 (Clause 551))
IEC 60050-826:2004, International Electrotechnical Vocabulary – Part 826: Electrical installations
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712.3 Terms and definitions
For the purpose of this document, the terms and definitions given in IEC 60050-826:2004 and the
following apply.
712.3.1
PV module
smallest completely environmentally protected assembly of interconnected PV cells
712.3.2
PV string
circuit of one or more series-connected modules
712.3.3
PV array
assembly of electrically interconnected PV modules, PV strings, PV sub-arrays and PV array combiner
boxes
Note 1 to entry: For the purposes of this document, a PV array is all components up to the d.c. input connection means of the
inverter or other power conversion electrical equipment or d.c. loads. A PV array does not include its foundation, tracking
apparatus, thermal control, and other such components.
Note 2 to entry: A PV array may consist of a single PV module, a single PV string, or several parallel-connected strings, or
several parallel-connected PV sub-arrays and their associated electrical components.
712.3.4
PV generator
PV array (712.3.3) including the inverter and the PV a.c. supply circuit
712.3.5
combiner box
switchgear assembly where PV sub-arrays or PV strings are connected and which may also contain
electrical accessories
712.3.6
PV sub-array
electrical subset of a PV array formed of parallel-connected PV strings
[SOURCE: IEC/TS 62548:2013, 3.1.42]
712.3.7
PV string cable
additional cable, not provided with the PV modules, for interconnecting a PV string and a PV
distribution board
712.3.8
PV array cable
output cable of a PV array
712.3.9
PV inverter
device which converts d.c. voltage and d.c. current of the PV array into a.c. voltage and a.c. current
712.3.10
PV a.c. supply cable
cable connecting the a.c. connection means of the PV inverter to a distribution board
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712.3.11
PV a.c. supply circuit
circuit connecting the a.c. connection means of the PV inverter to a distribution board
712.3.12
PV installation
erected electrical equipment of a PV power supply system
712.3.13
Standard Test Conditions
STC
test conditions specified in EN 60904-3 for PV cells and PV modules
712.3.14
open-circuit voltage under standard test conditions
U
OC STC
voltage under standard test conditions across an unloaded (open) PV module, PV string, PV array, PV
sub-array
712.3.15
open-circuit maximum voltage
U
OC MAX
maximum voltage across an unloaded (open) PV module, PV string, PV array, PV sub-array
Note 1 to entry: The method for determining U is provided in Annex B.
OC MAX
712.3.16
short-circuit current under standard test conditions
I
SC STC
short-circuit current under standard test conditions of a PV module, PV string, PV sub-array, PV array
712.3.17
short-circuit maximum current
I
SC MAX
short-circuit maximum current of a PV module, PV string, PV array
Note 1 to entry: The method for determining I is provided in Annex B.
SC MAX
712.3.18
SPD short-circuit current rating
I
SCPV
maximum prospective short-circuit current from the PV generator
712.3.19
d.c. side
part of a PV installation from the PV modules to the d.c. connection means of the PV inverter
712.3.20
a.c. side
part of a PV installation from the a.c. connection means of the PV inverter to the point of connection of
the PV supply cable to the electrical installation
712.3.21
Maximum Power Point Tracking
MPPT
internal control method of an inverter ensuring a search for operation at maximum power
712.3.22
MOD_MAX_OCPR
PV module maximum overcurrent protection rating
Note 1 to entry: See EN 61730-2.
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712.3.23
Lightning Protection System
LPS
complete system used to reduce physical damage due to lightning flashes to a structure
Note 1 to entry: It consists of both external and internal lightning protection systems.
712.3.24
functional bonding
bonding of a point or points in a system or inside electrical equipment for purposes other than
electrical safety
712.4 Protection for safety
712.41 Protection against electric shock
712.410 Introduction
712.410.101 Electrical equipment on the d.c. side shall be considered to be energized, even when
the a.c. side is disconnected from the grid or when the inverter is disconnected from the d.c. side.
712.410.3.5
Replace the requirements as follows:
The protective measures, specified in HD 60364-4-41:2007, Annex B, shall not be applied.
712.410.3.6
Replace the requirements as follows:
The protective measures, specified in HD 60364-4-41:2007, Annex C, shall not be applied.
712.410.102 On the d.c. side, one of the following protective measures shall be applied:
– double or reinforced insulation;
– extra-low voltage (SELV and PELV).
712.412 Protective measure: double or reinforced insulation
712.412.101 The electrical equipment, for example PV modules, wiring system (e.g. combiner box,
cables) used on the d.c. side (up to the d.c. connection means of the PV inverter) shall be class II or
equivalent insulation.
712.414 Protective measure: extra-low-voltage provided by SELV and PELV
712.414.101 For the use of SELV and PELV protective measures on the d.c. side, U shall not
OC MAX
exceed 120 V d.c.
712.414.4.5 If the nominal voltage exceeds 30 V d.c., basic protection shall be provided for SELV
and PELV circuits.
712.42 Protection against thermal effects
712.420.101 Safety of PV generator
NOTE Applicable national or local fire protection requirements apply.
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712.421 Protection against fire caused by electrical equipment
712.421.101 Protection against the effects of insulation faults on the d.c. side in case of
simple separation inside the inverter or on the a.c. side
It is recommended that a fault be eliminated with the shortest practicable delay.
712.421.101.1 An insulation monitoring device (IMD) shall be installed except where
712.421.101.2 applies, to verify the insulation status on the d.c. side throughout the life cycle of the PV
array.
NOTE Insulation monitoring devices (IMDs) complying with EN 61557-8 provide this function.
The monitoring function may be provided by an inverter with integrated insulation monitoring also
capable of detecting insulation faults.
712.421.101.2 Where functional bonding is applied to a live conductor inside the inverter on the
d.c. side, means shall be provided to ensure the interruption of the fault current in case of an insulation
fault to earth in accordance with Table 712.537.
712.43 Protection against overcurrent
712.431 Requirements according to the nature of the circuits
712.431.101 In a PV array with N strings (above 2 strings) in parallel, protective devices shall be
s
provided to protect each PV string where the following condition is met:
1,35 I < (N -1) I .
MOD_MAX_OCPR s SC MAX
In a PV array with one PV string or two PV strings in parallel, no overcurrent protective device is
required.
NOTE 1 If the inverter has several independent MPP-trackers and no reverse current can flow from one input
to another input by inverter design, then N is the number of strings connected to one individual d.c. input.
s
All strings connected in parallel shall have the same rated voltage.
NOTE 2 In practice that means that each string has the same number of modules connected in series using
equivalent modules.
712.431.102 For the protection of the PV strings, the use of protective devices as specified in
712.432 complies with the thermal withstand capability of the PV modules (as referred in EN 61730-1).
Where protective devices are required their rated current I shall comply with the following conditions:
n
1,1 I of the string ≤ I ≤ I
SC MAX n MOD_MAX_OCPR
NOTE The coefficient 1,1 is a safety margin for untimely operation of the protection devices taking into
account normal stress conditions.
The coefficient of 1,1 shall be adapted in case of special conditions, e.g. in case of reflections or
special PV module technologies.
Each string shall be protected individually by a protective device.
If several parallel strings are protected by one overcurrent protective device, the rated current, I , shall
n
comply with the following formula:
N × 1,1 I ≤ I ≤ I - (N - 1) × I
p SC MAX n MOD_MAX_OCPR p SC MAX
where
N is the number of parallel strings connected to the same overcurrent protective device.
p
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712.432 Nature of protective devices
712.432.101 Where overcurrent protective devices are required on the d.c. side according to
712.431.101, both polarities shall be protected, irrespective of the installation's configuration.
712.432.102 Blocking diodes used to connect the PV strings in parallel shall not be relied upon as a
means of protection against overcurrents.
712.432.103 The overcurrent protective devices of the d.c. side shall be either gPV fuses in
accordance with EN 60269-6 or fuse-combination units according to EN 60947-3, or devices in
accordance with EN 60947-2 or in accordance with EN 60898-2.
712.433 Protection against overload current
712.433.101 Protection of PV string cable
For the protection of the PV string cables, the following shall be considered:
– in a PV array with one PV string or two PV strings in parallel, no overcurrent protective device is
required (see also 712.431.101).
The continuous current-carrying capacity I of the PV string cable shall be greater than or equal to
z
the short-circuit maximum current of the string:
I of the string ≤ I
SC MAX z
– in a PV array with N strings in parallel with N greater than 2, the maximum reverse current
s s
flowing in the PV string cable is (N – 1) I . One of the following measures shall be used:
s SC MAX
• where PV string overcurrent protective device is not required in accordance with 712.431.101,
the continuous current-carrying capacity I of the PV string cables shall be greater than or
z
equal to the maximum reverse current:
(N – 1) I of the string ≤ I
s S
...
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