IEC 62548:2016

Photovoltaic (PV) arrays - Design requirements

IEC 62548:2016 sets out design requirements for photovoltaic (PV) arrays including DC array wiring, electrical protection devices, switching and earthing provisions. The scope includes all parts of the PV array up to but not including energy storage devices, power conversion equipment or loads. An exception is that provisions relating to power conversion equipment are covered only where DC safety issues are involved. The interconnection of small DC conditioning units intended for connection to PV modules are also included. The object of this document is to address the design safety requirements arising from the particular characteristics of photovoltaic systems. Direct current systems, and PV arrays in particular, pose some hazards in addition to those derived from conventional AC power systems, including the ability to produce and sustain electrical arcs with currents that are not greater than normal operating currents.

Groupes photovoltaïques (PV) - Exigences de conception

L'IEC 62548:2016 définit les exigences de conception relatives aux groupes photovoltaïques, y compris les dispositions concernant le câblage en courant continu des groupes, les dispositifs de protection électrique, la commutation et la mise à la terre. Le domaine d'application couvre toutes les parties du groupe photovoltaïque, à l'exception des dispositifs de stockage d'énergie, des équipements de conversion de puissance et des charges. Les dispositions relatives aux équipements de conversion de puissance ne sont cependant couvertes que dans le cas où il existe des problèmes de sécurité en courant continu. L'interconnexion de petites unités de traitement en courant continu destinées à la connexion des modules photovoltaïques est également couverte. Le présent document vise à traiter des exigences de sécurité de conception qui découlent des caractéristiques particulières des systèmes photovoltaïques. Les systèmes à courant continu, les groupes photovoltaïques en particulier, présentent certains dangers qui viennent s'ajouter à ceux des systèmes d'alimentation en courant alternatif conventionnels, notamment leur tendance à produire et à maintenir des arcs électriques sous des intensités de courant inférieures ou égales à celles des courants de fonctionnement normal.

General Information

• Status: Replaced
• Publication Date: 27-Sep-2016
• ICS: 27.160 - Solar energy engineering
• ICS: 33.160.30 - Audio systems
• Technical Committee: TC 82 - Solar photovoltaic energy systems
• Drafting Committee: WG 3 - TC 82/WG 3
• Current Stage: DELPUB - Deleted Publication
• Start Date: 07-Dec-2023
• Completion Date: 02-Sep-2019

Relations

• Replaces: IEC TS 62548:2013 - Photovoltaic (PV) arrays - Design requirements
• Effective Date: 05-Sep-2023
• Revised: IEC 62548-1:2023 - Photovoltaic (PV) arrays - Part 1: Design requirements
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 62548 ®
Edition 1.0 2016-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Photovoltaic (PV) arrays – Design requirements

Groupes photovoltaïques (PV) – Exigences de conception

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IEC 62548 ®
Edition 1.0 2016-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Photovoltaic (PV) arrays – Design requirements

Groupes photovoltaïques (PV) – Exigences de conception

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.160 ISBN 978-2-8322-3635-2

– 2 – IEC 62548:2016 © IEC 2016
CONTENTS
FOREWORD . 5
1 Scope and object . 7
2 Normative references. 7
3 Terms, definitions, symbols and abbreviated terms . 9
3.1 Terms, definitions and symbols. 9
3.2 Abbreviations . 16
4 Compliance with IEC 60364 (all parts) . 16
5 PV array system configuration. 16
5.1 General . 16
5.1.1 Functional configuration of a PV system . 16
5.1.2 PV system architectures . 17
5.1.3 Array electrical diagrams . 17
5.1.4 Use of PCE with multiple DC inputs . 22
5.1.5 Strings constructed using DC conditioning units . 23
5.1.6 Series-parallel configuration . 24
5.1.7 Batteries in systems . 25
5.1.8 Considerations due to prospective fault conditions within a PV array . 25
5.1.9 Considerations due to operating temperature . 25
5.1.10 Performance issues . 26
5.2 Mechanical design . 26
5.2.1 General . 26
5.2.2 Thermal aspects . 27
5.2.3 Mechanical loads on PV structures . 27
5.2.4 Corrosion . 27
6 Safety issues . 28
6.1 General . 28
6.1.1 Overview . 28
6.1.2 Separation of PV array from main AC power output circuits . 28
6.2 Protection against electric shock . 29
6.2.1 General . 29
6.2.2 Protective measure: double or reinforced insulation . 29
6.2.3 Protective measure: extra-low-voltage provided by SELV or PELV . 29
6.3 Protection against thermal effects . 29
6.4 Protection against the effects of insulation faults . 29
6.4.1 General . 29
6.4.2 Detection and fault indication requirements . 30
6.5 Protection against overcurrent . 34
6.5.1 General . 34
6.5.2 Requirement for overcurrent protection . 34
6.5.3 Requirement for string overcurrent protection . 34
6.5.4 Requirement for sub-array overcurrent protection . 35
6.5.5 Overcurrent protection sizing . 35
6.5.6 Overcurrent protection in PV systems connected to batteries . 37
6.5.7 Overcurrent protection location . 37
6.6 Protection against effects of lightning and overvoltage . 38
6.6.1 General . 38

6.6.2 Protection against overvoltage . 38
7 Selection and erection of electrical equipment . 39
7.1 General . 39
7.2 PV array maximum voltage . 40
7.3 Component requirements . 40
7.3.1 General . 40
7.3.2 PV modules . 41
7.3.3 PV array and PV string combiner boxes . 41
7.3.4 Circuit breakers . 42
7.3.5 Fuses . 42
7.3.6 Disconnectors and switch-disconnectors . 42
7.3.7 Cables . 43
7.3.8 Segregation of AC and DC circuits . 46
7.3.9 Plugs, sockets and connectors . 46
7.3.10 Wiring in combiner boxes . 47
7.3.11 Bypass diodes . 47
7.3.12 Blocking diodes . 47
7.3.13 Power conversion equipment (PCE) including DC conditioning units
(DCUs) . 47
7.4 Location and installation requirements . 48
7.4.1 Disconnecting means . 48
7.4.2 Earthing and bonding arrangements . 49
7.4.3 Wiring system . 54
8 Acceptance . 56
9 Operation/maintenance . 56
10 Marking and documentation . 56
10.1 Equipment marking . 56
10.2 Requirements for signs . 56
10.3 Identification of a PV installation . 57
10.4 Labelling of PV array and PV string combiner boxes . 57
10.5 Labelling of disconnection devices . 57
10.5.1 General . 57
10.5.2 PV array disconnecting device . 57
10.6 Documentation . 57
Annex A (informative) Examples of signs . 58
Annex B (informative) Examples of system functional earthing configurations in PV
arrays . 59
Annex C (informative) Blocking diode . 61
C.1 Introduction . 61
C.2 Use of blocking diodes to prevent overcurrent/fault current in arrays . 61
C.3 Examples of blocking diode use in fault situations . 61
C.3.1 General . 61
C.3.2 Short circuit in PV string . 61
C.4 Specification of blocking diode . 63
C.5 Heat dissipation design for blocking diode . 63
Annex D (informative) Arc fault detection and interruption in PV arrays . 65
Annex E (normative) DVC limits . 66
Bibliography . 67

– 4 – IEC 62548:2016 © IEC 2016

Figure 1 – General functional configuration of a PV powered system . 17
Figure 2 – PV array diagram – single string example . 18
Figure 3 – PV array diagram – multiple parallel string example . 19
Figure 4 – PV array diagram – multiple parallel string example with array divided into
sub-arrays . 20
Figure 5 – PV array example using a PCE with multiple MPPT DC inputs . 21
Figure 6 – PV array example using a PCE with multiple DC inputs internally connected
to a common DC bus . 22
Figure 7 – PV string constructed using DC conditioning units . 24
Figure 8 – Example of a PV array diagram where strings are grouped under one
overcurrent protection device per group . 36
Figure 9 – Examples of reinforced protection of wiring . 45
Figure 10 – PV array exposed conductive parts functional earthing/bonding decision tree . 51
Figure 11 – Exposed conductive parts earthing in a PV array . 52
Figure 12 – Examples of PV string wiring with minimum loop area . 55
Figure A.1 – Example of sign required on PV array combiner boxes (10.4) . 58
Figure A.2 – Example of switchboard sign for identification of PV on a building . 58
Figure B.1 – System functional earthing/grounding . 59
Figure B.2 – Examples different PV configurations in common use . 60
Figure C.1 – Effect of blocking diode where there is a short circuit in PV string . 62
Figure C.2 – Effect of blocking diode where there is an earth fault on a system with
earthing on the minus side . 62
Figure C.3 – Effect of blocking diode where there is an earth fault on a system with
positive side earthing . 63
Figure D.1 – Examples of types of arcs in PV arrays . 65

Table 1 – Requirements for different system types based on PCE isolation and PV
array functional earthing . 31
Table 2 – Minimum insulation resistance thresholds for detection of failure of
insulation to earth . 32
Table 3 – Rated current of automatic earth fault interrupting means . 33
Table 4 – Voltage correction factors for crystalline and multi-crystalline silicon PV
modules . 40
Table 5 – Minimum current rating of circuits . 44
Table 6 – Disconnection device requirements in PV array installations . 49
Table E.1 – Summary of the limits of the decisive voltage classes . 66

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PHOTOVOLTAIC (PV) ARRAYS –
DESIGN REQUIREMENTS
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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6) All users should ensure that they have the latest edition of this publication.
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62548 has been prepared by IEC technical committee 82: Solar
photovoltaic energy systems.
This International Standard cancels and replaces the first edition of IEC TS 62548 published
in 2013.
This International Standard includes the following significant technical changes with respect
to IEC TS 62548:
a) provisions for systems including DC to DC conditioning units;
b) considerable revision of Clause 6 on safety issues which includes provisions for protection
against electric shock including array insulation monitoring and earth fault detection.

– 6 – IEC 62548:2016 © IEC 2016
The text of this document is based on the following documents:
FDIS Report on voting
82/1149/FDIS 82/1166/RVD
Full information on the voting for the approval of this document can be found in the report on
voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
Attention is drawn to the co-existence of IEC 60364-7-712 and IEC 62548. Both standards
have been developed in close coordination by different technical committees.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
PHOTOVOLTAIC (PV) ARRAYS –
DESIGN REQUIREMENTS
1 Scope and object
This International Standard sets out design requirements for photovoltaic (PV) arrays
including DC array wiring, electrical protection devices, switching and earthing provisions. The
scope includes all parts of the PV array up to but not including energy storage devices, power
conversion equipment or loads. An exception is that provisions relating to power conversion
equipment are covered only where DC safety issues are involved. The interconnection of
small DC conditioning units intended for connection to PV modules are also included.
The object of this document is to address the design safety requirements arising from the
particular characteristics of photovoltaic systems. Direct current systems, and PV arrays in
particular, pose some hazards in addition to those derived from conventional AC power
systems, including the ability to produce and sustain electrical arcs with currents that are not
greater than normal operating currents.
In grid connected systems, the safety requirements of this document are however critically
dependent on the inverters associated with PV arrays complying with the requirements of
IEC 62109-1 and IEC 62109-2.
Installation requirements are also critically dependent on compliance with the
IEC 60364 series (see Clause 4).
PV arrays of less than 100 W and less than 35 V DC open circuit voltage at STC are not
covered by this document.
PV arrays in grid connected systems connected to medium or high voltage systems are not
covered in this document. Variations and additional requirements for large-scale ground
mounted PV power plants with restricted access to personnel will also be addressed in
IEC TS 62738 .
Additional requirements may be needed for more specialized installations, for example
concentrating systems, tracking systems or building integrated PV.
The present international standard also includes extra protection requirements of PV arrays
when they are directly connected with batteries at the DC level.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
IEC 60228, Conductors of insulated cables
IEC 60269-6, Low-voltage fuses – Part 6: Supplementary requirements for fuse-links for the
protection of solar photovoltaic energy systems
___________
Under preparation. Stage at the time of publication: IEC 2CD 62738.

– 8 – IEC 62548:2016 © IEC 2016
IEC 60287 (all parts), Electric cables – Calculation of the current rating
IEC 60364-1, Low-voltage electrical installations – Part 1: Fundamental principles,
assessment of general characteristics, definitions
IEC 60364-4 (all parts), Low-voltage electrical installations – Part 4: Protection for safety
IEC 60364-4-41:2005, Low-voltage electrical installations – Part 4-41: Protection for safety –
Protection against electric shock
IEC 60364-5 (all parts), Electrical installations of buildings – Part 5: Selection and erection of
electrical equipment
IEC 60364-5-52, Low-voltage electrical installations – Part 5-52: Selection and erection of
electrical equipment – Wiring systems
IEC 60364-5-54, Low-voltage electrical installations – Part 5-54: Selection and erection of
electrical equipment – Earthing arrangements and protective conductors
IEC 60364-6, Low-voltage electrical installations – Part 6: Verification
IEC 60445:2010, Basic and safety principles for man-machine interface, marking and
identification – Identification of equipment terminals, conductor terminations and conductors
IEC 60529, Degrees of protection provided by enclosures (IP Code)
IEC 60898-2, Circuit-breakers for overcurrent protection for household and similar
installations – Part 2: Circuit-breakers for a.c. and d.c. operation
IEC 60947 (all parts), Low-voltage switchgear and controlgear
IEC 60947-1, Low-voltage switchgear and controlgear – Part 1: General rules
IEC 60947-2, Low-voltage switchgear and controlgear – Part 2: Circuit-breakers
IEC 60947-3, Low-voltage switchgear and controlgear – Part 3: Switches, disconnectors,
switch-disconnectors and fuse-combination units
IEC 61215 (all parts), Terrestrial photovoltaic (PV) modules − Design qualification and type
approval
IEC 61557-2, 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 2: Insulation resistance
IEC 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 61643-21, Low-voltage surge protective devices – Part 21: Surge protective devices
connected to telecommunications and signalling networks – Performance requirements and
testing methods
IEC 61643-22, Low-voltage surge protective devices – Part 22: Surge protective devices
connected to telecommunications and signalling networks – Selection and application
principles
IEC 61730-1, Photovoltaic (PV) module safety qualification − Part 1: Requirements for
construction
IEC 61730-2, Photovoltaic (PV) module safety qualification − Part 2: Requirements for testing
IEC 62109-1:2010, Safety of power converters for use in photovoltaic power systems – Part 1:
General requirements
IEC 62109-2, Safety of power converters for use in photovoltaic power systems – Part 2:
Particular requirements for inverters
IEC 62305-2, Protection against lightning – Part 2: Risk management
IEC 62305-3, Protection against lightning – Part 3: Physical damage to structures and life
hazard
IEC 62446-1, Photovoltaic (PV) systems – Requirements for testing, documentation and
maintenance – Part 1: Grid connected systems – Documentation, commissioning tests and
inspection
IEC 62852, Connectors for DC-application in photovoltaic systems – Safety requirements and
tests
IEC 62930, Electric cables for photovoltaic systems
EN 50539-11, Low-voltage surge protective devices – Surge protective devices for specific
application including DC – Part 11: Requirements and tests for SPDs in photovoltaic
applications
3 Terms, definitions, symbols and abbreviated terms
3.1 Terms, definitions and symbols
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
blocking diode
diode connected in series with module(s), panel(s), sub-arrays and array(s) to block reverse
current into such module(s), panel(s), sub-array(s) and array(s)
3.1.2
bonding conductor
conductor provided for functional or protective equipotential bonding
3.1.3
bypass diode
diode connected across one or more cells in the forward current direction to allow the module
current to bypass shaded or broken cells to prevent hot spot or hot cell damage resulting from
the reverse voltage biasing from the other cells in that module

– 10 – IEC 62548:2016 © IEC 2016
3.1.4
cable
assembly of one or more conductors and/or optical fibers, with a protective covering and
possibly filling, insulating and protective material
[SOURCE: IEC 60050-151:2001,151-12-38]
3.1.5
charge controller
unit used between a battery and a PV array to regulate charge delivered to the battery
3.1.6
closed electrical operating area
room or location for electrical equipment to which access is restricted to skilled or instructed
persons by the opening of a door or the removal of a barrier by the use of a key or tool and
which is clearly marked by appropriate warning signs
3.1.7
competent person
person, who has acquired, through training, qualification or experience or a combination of
these, the knowledge and skill enabling that person to perform the required task correctly
3.1.8
DC conditioning units
DCU
unit connected to individual PV modules or groups of PV modules to allow DC conditioning of
the PV output
3.1.9
decisive voltage classification
DVC
highest voltage which occurs continuously between any two arbitrary live parts or between
live parts and earth of the PV array during worst-case rated operating conditions when used
as intended
Note 1 to entry: See decisive voltage class limits in Annex E.1.
[SOURCE: IEC 62109-1:2010, 3.12 modified — The word "classification" has been added to
the term, a note has been added, and the definition has been modified to make applicable to
PV array application.]
3.1.10
disconnector
mechanical switching device which provides, in the open position, an isolating distance in
accordance with specified requirements
Note 1 to entry: A disconnector is capable of opening and closing a circuit when either negligible current is
broken or made, or when no significant change in the voltage across the terminals of each of the poles of the
disconnector occurs. It is also capable of carrying currents under normal circuit conditions and carrying currents for
a specified time under abnormal conditions such as those of short circuit.
[SOURCE: IEC 60050-441:2000, 441-14-05]
3.1.11
double insulation
insulation comprising both basic insulation and supplementary insulation
[SOURCE: IEC 60050-195:1998, 195-06-08]

3.1.12
extraneous conductive part
conductive part not forming part of the electrical installation and liable to introduce an electric
potential, generally the electric potential of a local earth
[SOURCE: IEC 60050-851:2008, 851-14-57, modified — The note has been deleted.]
3.1.13
functionally earthed PV array
PV array that has one conductor intentionally connected to earth for purposes other than
safety
Note 1 to entry: Such a system is not considered to be an earthed array.
Note 2 to entry: Examples of functional array earthing include earthing one conductor through an impedance, or
only temporarily earthing the array for functional or performance reasons.
Note 3 to entry: In PCE intended for an array not connected to a functional earth that uses a resistive
measurement network to measure the array impedance to earth, that measurement network is not considered a
form of functional earth.
3.1.14
independent manual operation
independent manual operation of a mechanical switching device
stored energy operation where the energy originates from manual power, stored and released
in one continuous operation (e.g. spring release), such that the speed and force of the
operation are independent of the action of the operator
[SOURCE: IEC 60050-441:2000, 441-16-16, modified — The brackets have been added to the
definition.]
3.1.15
irradiance
G
electromagnetic radiated solar power per unit of area
Note 1 to entry: Expressed in W/m .
[SOURCE: IEC TS 61836:2007, 3.6.25, modified — The adjective "solar" has been added to
the definition, and the note has been replaced.]
3.1.16
I
MOD_MAX_OCPR
PV module maximum overcurrent protection rating determined by IEC 61730-2
Note 1 to entry: This is often specified by module manufacturers as the maximum series fuse rating which refers
to the fuse rated current in IEC 60269-1 and IEC 60269-6.
3.1.17
I
n
nominal rated current
3.1.18
I
SC ARRAY
short-circuit current of the PV array at standard test conditions (STC), and is equal to
I = I × N
SC ARRAY SC MOD S
where
N is the total number of parallel-connected PV strings in the PV array
S
– 12 – IEC 62548:2016 © IEC 2016
3.1.19
I
SC MOD
short circuit current of a PV module or PV string at standard test conditions (STC), as
specified by the manufacturer in the product specification plate
Note 1 to entry: As PV strings are a group of PV modules connected in series, the short circuit current of a string
is equal to I .
SC MOD
3.1.20
I
SC S-ARRAY
short circuit current of a PV sub-array at standard test conditions (STC), and equal to
I = I × N
SC S-ARRAY SC MOD SA
where
N is the number of parallel-connected PV strings in the PV sub-array
SA
3.1.21
separated PCE
PCE with at least simple separation between the AC output circuits and PV circuits
Note 1 to entry: The separation may be either integral to the PCE or provided externally by a transformer with at
least simple separation.
3.1.22
junction box
closed or protected enclosure in which circuits are electrically connected
[SOURCE: IEC TS 61836: 2007, 3.2.16]
3.1.23
live part
conductor or conductive part intended to be energized in normal operation, including a neutral
conductor, but by convention not a PEN conductor or PEM conductor or PEL conductor
Note 1 to entry: This concept does not necessarily imply a risk of electric shock.
[SOURCE: IEC 60050-195:1998, 195-02-19]
3.1.24
low voltage
voltage exceeding DVC-A, but not exceeding 1 000 V AC or 1 500 V DC
3.1.25
main earthing terminal
terminal or bar provided for the connection of the main protective earthing conductor, bonding
conductors and, if provided, the conductor for functional earthing
3.1.26
maximum power point tracking
MPPT
control strategy whereby PV array operation is always at or near the point on a PV device's
current-voltage characteristic where the product of electric current and voltage yields the
maximum electrical power under specified operating conditions
3.1.27
non-separated PCE
PCE without at least simple separation between the AC output and PV circuits

3.1.28
PEL conductor
conductor combining the functions of both a protective earthing conductor and a line
conductor
[SOURCE: IEC 60050-195:1998,195-02-14]
3.1.29
PEM conductor
conductor combining the functions of both a protective earthing conductor and a mid-point
conductor
[SOURCE: IEC 60050-195:1998, 195-02-13]
3.1.30
PEN conductor
conductor combining the functions of both a protective earthing conductor and a neutral
conductor
[SOURCE: IEC 60050-195:1998, 195-02-12]
3.1.31
power conversion equipment
PCE
system that converts the electrical power delivered by the PV array into the appropriate
frequency and/or voltage values to be delivered to the load, or stored in a battery or injected
into the electricity grid
Note 1 to entry: See Figure 2 to Figure 4.
3.1.32
protective earthing
earthing of a point in an equipment or in a system for safety reasons
3.1.33
PV array
assembly of electrically interconnected PV modules, PV strings or PV sub-arrays
Note 1 to entry: For the purposes of this document a PV array is all components up to the DC input terminals of
the inverter or other power conversion equipment or DC loads.
Note 2 to entry: A PV array does not include its foundation, tracking apparatus, thermal control, and other such
components.
Note 3 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 (see Figure 2 to
Figure 4). For the purposes of this document the boundary of a PV array is the output side of the PV array
disconnecting device.
3.1.34
PV array main cable
output cable of a PV array that carries the total output current of the array
3.1.35
PV cell
most elementary device that exhibits the photovoltaic effect, i.e the direct non-thermal
conversion of radiant energy into electrical energy
Note 1 to entry: The preferred term is "solar photovoltaic cell" or "photovoltaic cell", colloquially referred to as a
"solar cell".
– 14 – IEC 62548:2016 © IEC 2016
Note 2 to entry: The original definition from IEC TS 61836:2007, 3.1.43 a), has been modified and expanded for
clarity.
3.1.36
PV array combiner box
junction box where PV sub-arrays are connected and which may also contain overcurrent
protection and/or switch-disconnection devices
Note 1 to entry: Small arrays generally do not contain sub-arrays but are simply made up of strings, whereas
large arrays are generally made up of multiple sub-arrays.
3.1.37
PV array maximum voltage
U corrected for the worst-case conditions of ambient temperature
OC ARRAY
Note 1 to entry: See 7.2.
3.1.38
PV module
complete and environmentally protected assembly of interconnected photovoltaic cells
[SOURCE: IEC TS 61836:2007, 3.1.43 f), modified — The adjective "photovoltaic" has been
replaced by "PV" in the term.]
3.1.39
PV string
circuit of one or more series-connected modules
[SOURCE: IEC 61836:2007, 3.3.56, modified — The adjective "photovoltaic" has been
replaced by "PV", and the words "one or more" have been added for clarity.]
3.1.40
PV string cable
cable interconnecting the modules in a PV string, or connecting the string to a combiner box,
PCE or other DC loads
Note 1 to entry: See Figure 2 to Figure 4.
3.1.41
PV string combiner box
junction box where PV strings are connected which may also contain overcurrent protection
devices and/or switch-disconnectors
Note 1 to entry: See Figure 4.
Note 2 to entry: PV string combiner boxes are only relevant for PV arrays that are divided into sub-arrays.
3.1.42
PV sub-array
electrical subset of a PV array formed of parallel connected PV strings
3.1.43
PV sub-array cable
output cable of a PV sub-array that carries the output current of its associated sub-array
Note 1 to entry: PV sub-array cables are only relevant for PV arrays that are div
...