IEC TS 62257-9-1:2016

IEC TS 62257-9-1 ®
Edition 2.0 2016-09
TECHNICAL
SPECIFICATION
colour
inside
Recommendations for renewable energy and hybrid systems for rural
electrification –
Part 9-1: Integrated systems – Micropower systems

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IEC TS 62257-9-1 ®
Edition 2.0 2016-09
TECHNICAL
SPECIFICATION
colour
inside
Recommendations for renewable energy and hybrid systems for rural

electrification –
Part 9-1: Integrated systems – Micropower systems

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.160 ISBN 978-2-8322-3585-0

– 2 – IEC TS 62257-9-1:2016 © IEC 2016
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references. 9
3 Terms and definitions . 9
4 General . 11
4.1 Boundary of a micropower plant . 11
4.2 Composition of a micropower plant . 12
4.3 General functional layout of a micropower plant . 12
5 Design . 13
5.1 Design criteria . 13
5.2 Power generation mix . 14
5.2.1 General . 14
5.2.2 Internal combustion generator sets . 15
5.3 Electrical design . 15
5.3.1 System voltage selection . 15
5.3.2 Interconnection of generators . 16
5.4 Mechanical and civil works . 16
5.4.1 Civil works . 16
5.4.2 Technical room . 16
5.4.3 Battery room . 17
5.4.4 Specific requirements . 17
6 Safety issues . 17
6.1 Electrical issues . 17
6.1.1 General . 17
6.1.2 Specific requirements . 17
6.2 Mechanical issues . 21
6.3 Thermal and fire issues . 21
6.4 Noise issues . 21
6.5 Access security . 22
7 Erection of equipment . 22
7.1 Siting . 22
7.1.1 Photovoltaic array . 22
7.1.2 Wind turbine . 22
7.1.3 Micro-hydro turbine . 22
7.1.4 Generator set . 23
7.1.5 Technical room . 23
7.1.6 Battery bank (battery enclosure) . 23
7.2 Equipment installation . 24
7.2.1 Mechanical . 24
7.2.2 Electrical . 24
8 Acceptance process. 27
8.1 General . 27
8.2 Phase 1: Preparation . 27
8.3 Phase 2: Documentation . 27

8.4 Phase 3: Commissioning . 27
8.4.1 Step 1: Evaluation of the conformity of the installed system with the
accepted design . 27
8.4.2 Step 2: Evaluation of qualification of the installation . 27
8.4.3 Step 3: Preliminary tests . 27
8.4.4 Step 4: Performance testing . 28
8.5 Phase 4: Agreement . 29
8.6 Commissioning records . 29
9 Operation, maintenance and replacement . 29
10 Marking and documentation . 29
10.1 Marking . 29
10.1.1 Information for emergency services . 29
10.1.2 Information for maintenance . 29
10.1.3 Information for batteries . 30
10.1.4 Signs . 30
10.2 Documentation . 30
Annex A (informative) Selectivity of protection . 32
Annex B (informative) Risk assessment of lightning stroke . 34
B.1 General . 34
B.2 Risk assessment simplified methodology . 34
B.3 Risk assessment multi-criteria methodology . 34
Annex C (normative) Voltage domains . 37
Annex D (informative) Battery room . 38
D.1 Administrative formalities . 38
D.2 Battery siting . 38
D.3 Characteristics of the battery storage site: specific battery room or locker . 38
D.4 Electrical equipment . 39
D.5 Safety instructions . 40
D.6 Battery enclosure examples (informative) . 40
Annex E (informative) Energy fraction calculations . 45
Annex F (informative) Noise control . 46
F.1 General . 46
F.2 Assessment of noise annoyance . 46
F.3 Principles of noise attenuation . 46
F.4 Noise reduction methods for specific items of equipment . 47
F.4.1 Generator sets . 47
F.4.2 Wind turbines . 47
F.4.3 Inverters and other electronic equipment . 47
Annex G (informative) Commissioning record sheet (examples) . 48
Bibliography . 59

Figure 1 – Micropower system limits . 12
Figure 2 – Example of functional layout for a micropower plant supplying a.c. energy . 13
Figure 3 – Interconnection configuration with d.c. bus and a.c. bus . 16
Figure 4 – Interconnection configuration with a.c. bus only . 16
Figure 5 – Example of protection against effects of lightning and over-voltage for
generators with two live conductors output (d.c. or a.c.) TNS P+N . 18

– 4 – IEC TS 62257-9-1:2016 © IEC 2016
Figure 6 – Example of protection against effects of lightning over-voltage for three
phase generators with four live a.c. conductors (TNS P+N scheme) – Generator side. 19
Figure 7 – Example of a simplified lightning protection including a crow’s foot earth
termination . 19
Figure 8 – Protection of a photovoltaic array . 20
Figure 9 – Wiring arrangement for equipotential link . 21
Figure A.1 – Example of the selectivity of protection . 33
Figure D.1 – Two examples of a battery installed in a dedicated equipment room
showing clearances from equipment . 41
Figure D.2 – Example of a battery enclosure within a room where the battery
enclosure is vented to outside the building . 42
Figure D.3 – Example of a battery enclosure with equipment enclosure immediately
adjacent . 43
Figure D.4 – Example of a battery enclosure with the intake and outlet vents on the
same wall . 44

Table 1 – Minimum dimensions for lightning protection wires . 20
Table 2 – Cross-section of 230 V a.c. power cables . 25
Table 3 – Fuse ratings for protection from short-circuiting in 230 V/400 V a.c. circuits . 26
Table 4 – Fuse ratings for protection from short-circuiting in 120 V/208 V a.c. circuits . 26
Table 5 – Circuit-breaker ratings for protection from short-circuiting . 26
Table B.1 – Stake index values . 34
Table B.2 – Construction index values . 35
Table B.3 – Height index values . 35
Table B.4 – Situation index values . 35
Table B.5 – Lightning prevalence index values . 35
Table B.6 – Assessment of risk and need for protection . 36
Table C.1 – Voltage domains . 37

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RECOMMENDATIONS FOR RENEWABLE ENERGY AND
HYBRID SYSTEMS FOR RURAL ELECTRIFICATION –

Part 9-1: Integrated systems – Micropower systems

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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The main task of IEC technical committees is to prepare International Standards. In
exceptional circumstances, a technical committee may propose the publication of a technical
specification when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC 62257-9-1, which is a technical specification, has been prepared by IEC technical
committee 82: Solar photovoltaic energy systems.
This second edition cancels and replaces the first edition, issued in 2008. It constitutes a
technical revision.
– 6 – IEC TS 62257-9-1:2016 © IEC 2016
The main technical changes with regard to the previous edition are as follows:
• Changing the voltage range covered by the technical specification to a.c. nominal voltage
below 1 000 V and d.c. nominal voltage below 1 500 V (introduction)
• Defining the rating of the microgrids to be the output of the microgrid (introduction)
• Including 240 V 1-Ø/415 V 3-Ø, in the voltage levels (introduction)
• Specifying Non-separated MPPTs connecting LV d.c. arrays to ELV d.c. battery banks are
not allowed (5.3.1.1)
• Noting that systems can now include a.c. bus arrangements and use MPPT's as the solar
controllers thus increasing the internal voltages that occur in systems (5.3.1.2)
• Increased equipotential bonding for lightning protection from minimum 10 mm to minimum
16 mm (6.1.2.2)
• Included a new subclause (7.1.6) on battery enclosures including possible arrangements
shown as Clause D.6
• Rewritten LV Multiple sources (7.2.2.3.1)
• Included start-up procedure in documentation (10.2)
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
82/1028/DTS 82/1087/RVC
Full information on the voting for the approval of this technical specification 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.
This technical specification is to be used in conjunction with the IEC 62257 series and with
future parts of this series as and when they are published.
A list of all parts in the IEC 62257 series, published under the general title Recommendations
for renewable energy and hybrid systems for rural electrification, can be found on the IEC
website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.
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.
INTRODUCTION
The IEC 62257 series of documents intends to provide to the different players involved in
rural electrification projects (such as project implementers, project contractors, project
supervisors, installers, etc.) documents for the setting-up of renewable energy and hybrid
systems with a.c. nominal voltage below 1 000 V, and d.c. nominal voltage below 1 500 V.
These documents are recommendations:
• to choose the right system for the right place;
• to design the system;
• to operate and maintain the system.
These documents are focused only on rural electrification concentrating on, but not specific
to, developing countries. They must not be considered as all-inclusive to rural electrification.
The documents try to promote the use of renewable energies in rural electrification; they do
not deal with clean mechanisms developments at this time (CO emission, carbon credit,
etc.). Further developments in this field could be introduced in future steps.
This consistent set of documents is best considered as a whole with different parts
corresponding to items for safety, sustainability of systems and at the lowest life-cycle cost as
possible. One of the main objectives is to provide the minimum sufficient requirements,
relevant to the field of application, that is, small renewable energy and hybrid off-grid
systems.
– 8 – IEC TS 62257-9-1:2016 © IEC 2016
RECOMMENDATIONS FOR RENEWABLE ENERGY AND
HYBRID SYSTEMS FOR RURAL ELECTRIFICATION –

Part 9-1: Integrated systems – Micropower systems

1 Scope
Decentralized Rural Electrification Systems (DRES) are designed to supply electric power for
sites which are not connected to a large interconnected system, or a national grid, in order to
meet basic needs.
The majority of these sites are:
• isolated dwellings;
• village houses;
• community services (public lighting, pumping, health centres, places of worship or cultural
activities, administrative buildings, etc.);
• economic activities (workshops, micro-industry, etc.).
The DRESs fall into the following three categories:
• process electrification systems (for example, for pumping);
• individual electrification systems (IES) for single users;
• collective electrification systems (CES) for multiple users.
Process or individual electrification systems exclusively consist of two subsystems:
• an electric energy generation subsystem;
• the user's electrical installation.
Collective electrification systems, however, consist of three subsystems:
• an electric energy generation subsystem;
• a distribution subsystem, also called microgrid;
• user’s electrical installations including interface equipment between the installations and
the microgrid.
This technical specification applies to a micropower plant which is the electric energy
generation subsystem associated with a decentralized rural electrification system.
It provides general requirements for the design, erection and operation of micropower plants
and general requirements to ensure the safety of persons and property.
The micropower plants covered by this specification are low-voltage a.c., three-phase or
single-phase, with rated capacity less than, or equal to, 100 kVA. The rated capacity is at the
electrical output of the micropower plant, that is, the upstream terminals of the main switch
between the micropower plant and the microgrid. They do not include voltage transformation.
The voltage levels covered under this specification are:
• the 240 V 1-Ø/415 V 3-Ø, the 230 V 1-Ø/400 V 3-Ø, the 220 V 1-Ø/380 V 3-Ø, and the
120 V 1-Ø/208 V 3-Ø systems at 60 Hz or 50 Hz; or obeyed by local code.

• the ELV (less than 120 V) d.c. systems.
The requirements cover “centralized” micropower plants for application in:
• process electrification;
• individual electrification systems and collective electrification systems.
It does not apply to distributed generation on microgrids.
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 60364 (all parts), Low-voltage electrical installations
IEC 60364-5-53:2001, Electrical installations of buildings – Part 5-53: Selection and erection
of electrical equipment – Isolation, switching and control
IEC TS 62257-2:2015, Recommendations for renewable energy and hybrid systems for rural
electrification – Part 2: From requirements to a range of electrification systems
IEC TS 62257-4:2015, Recommendations for renewable energy and hybrid systems for rural
electrification – Part 4: System selection and design
IEC TS 62257-5:2015, Recommendations for renewable energy and hybrid systems for rural
electrification – Part 5: Protection against electrical hazards
IEC TS 62257-6:2015, Recommendations for renewable energy and hybrid systems for rural
electrification – Part 6: Acceptance, operation, maintenance and replacement
IEC TS 62257-7-1:2010, Recommendations for small renewable energy and hybrid systems
for rural electrification – Part 7-1: Generators – Photovoltaic generators
IEC TS 62257-7-3:2008, Recommendations for small renewable energy and hybrid systems
for rural electrification – Part 7-3: Generator set – Selection of generator sets for rural
electrification systems
IEC TS 62257-9-2:2016, Recommendations for renewable energy and hybrid systems for rural
electrification – Part 9-2: Integrated systems – Microgrids
IEC TS 62257-9-4:2016, Recommendations for renewable energy and hybrid systems for rural
electrification – Part 9-4: Integrated systems – User installation
IEC 62548:2016, Photovoltaic (PV) arrays – Design requirements
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

– 10 – IEC TS 62257-9-1:2016 © IEC 2016
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
generator set
equipment producing electricity from a fossil fuel; it consists basically of an internal
combustion engine producing mechanical energy and a generator which converts the
mechanical energy into electrical energy and mechanical transmission, support and assembly
components
3.2
reference earth
reference ground (US)
conductive part of the earth, considered as conductive, the electric potential of which is
conventionally taken as zero, being outside the zone of influence of any earthing arrangement
[SOURCE: IEC 60050-826:2004, 826-13-01]
3.3
skilled person
person with relevant education or experience to enable him/her
• to perceive risks and to avoid hazards which electrical, chemical or mechanical equipment
may create;
• to perform or supervise correctly the required task
3.4
instructed person
person adequately advised or supervised by skilled persons to enable him/her
• to perceive risks and to avoid hazards which electrical, chemical or mechanical equipment
may create;
• to perform correctly the required task
3.5
ordinary person
person who is neither a skilled person nor an instructed person
3.6
licenced person
person who is authorized to perform electrical work under the appropriate state or territory
statutes and regulations
Note 1 to entry: Only skilled or instructed persons can be licenced.
3.7
microgrid
subsystem of a DRES intended for power distribution, the prefix “micro” being intended to
express the low level of transmitting capacity
3.8
micropower plant
subsystem of a DRES for power generation, the prefix “micro” being intended to express the
low power level generated
3.9
protective conductor
identification: PE
conductor provided for purposes of safety, for example protection against electric shock
[SOURCE: IEC 60050-826:2004, 826-13-22]
3.10
PEN conductor
conductor combining the functions of both a protective earthing conductor and a neutral
conductor
[SOURCE: IEC 60050-826:2004, 826-13-25]
3.11
power line
overhead or underground line installed to convey electrical energy for any purpose other than
communication
3.12
renewable energy
RE
energy generated from natural resources such as sunlight, wind, rain, waves, tides,
geothermal heat (list not exhaustive), which are renewable (naturally replenished)
Note 1 to entry: Renewable energy technologies include solar power, wind power, hydroelectricity, micro hydro,
biomass, biofuels (list not exhaustive).
3.13
selectivity of protection
ability of a protection to identify the faulty section and/or phase(s) of a power system
[SOURCE: IEC 60050-448: 1995, 448-11-06]
3.14
lightning arrester
surge diverter
surge arrester
device intended to protect the electrical apparatus from high transient overvoltages and to
limit the duration and frequently the amplitude of the follow-on current
[SOURCE: IEC 60050-811: 1991, 811-31-09]
3.15
technical room
cabinet
room or cabinet in which are located devices and apparatus dedicated to inter-connection of
the different generators, protection of the different circuits, monitoring and control of the
micropower plant and interfacing with the application
4 General
4.1 Boundary of a micropower plant
The micropower plant is defined as illustrated in Figure 1.

– 12 – IEC TS 62257-9-1:2016 © IEC 2016
Electrification system
Energy production Distribution
Demand
subsystem subsystem subsystem
Microgrid For example, user’s
Micropower
installation
system
Loads
Other
User interface
Generators
equipment
IEC
Figure 1 – Micropower system limits
The physical limits of the micropower plant are the upstream terminals of the main switch
between the micropower plant and the microgrid.
4.2 Composition of a micropower plant
A micropower plant includes:
• one or several generators;
• storage devices (if needed) and associated charge controller;
• other equipment, such as
– energy management device;
– energy converter;
– telecommunication equipment (if any);
– main board;
– interfaces:
• between generators;
• between the micropower plant and the microgrid or the application;
• between the micropower plant and the operator;
– switches;
– protection devices;
• equipotential bonding;
• earthing system;
• civil works.
4.3 General functional layout of a micropower plant
Figure 2 illustrates an example of the general functional layout of a micropower plant
combining the different equipment listed in 4.2.

Generator set room Storage room
Technical room
AC AC DC DC
Battery Charge
Generator Generator Generator Generator
bank controller
Energy manager
1 set 1 2
Energy
converter
Board
To microgrid
or application
IEC
Figure 2 – Example of functional layout for a micropower plant supplying a.c. energy
5 Design
5.1 Design criteria
The design of any system should be guided by a number of criteria, determined by the project
implementer (for example, user’s affordable needs, lowest economic life-cycle cost, lowest
environmental impact, site constraints). Some of the major areas to be considered are:
• average daily design d.c. load energy and average daily design a.c. load energy;
• maximum and surge power demand;
• system bus bar voltage and service (output) voltage;
• energy resources (sun, wind, hydro, fuel, biomass, etc.);
• budget constraints;
• power quality (for example, waveform quality or continuity of supply);
• environmental impact (for example, trimming or removal of trees for a PV system, civil
works and diversion of water in a hydro system);
• use of existing equipment;
• acceptable extent of generator set running versus renewable energy contribution;
• acceptable noise levels;
• availability of spare parts and maintenance service;
• site accessibility;
• acceptable level of reliability and maintenance;
• level of automation versus direct user control;
• aesthetics.
The level of reliability should be determined in order to match the quality of service which is
intended to be provided to the user in the general specification.

– 14 – IEC TS 62257-9-1:2016 © IEC 2016
NOTE The necessity for special design techniques to achieve very high levels of reliability will depend on the
application and on the willingness to pay of customers for high quality of service.
The provision of electrical energy should be dealt with in the context of provision of all energy
services to the dwelling or group of buildings. Such an integrated approach to the provision of
energy services should yield the lowest cost outcome and can ensure lower overall energy
consumption from non-renewable sources.
The design process performance specifications shall take into account the considerations
above and shall be based on renewable energy resource data including adjustments for site
conditions and design parameters (for example, PV array tilt angle and orientation, wind
turbine tower height).
Major system parameters which shall be provided by the design process (for annual, seasonal
or monthly periods, as appropriate to the basis of the design) are:
• load management strategies or conditions necessary for performance as specified;
• design d.c. load energy and design a.c. load energy;
• maximum and surge demand;
• average daily energy output of each renewable energy generator under design conditions;
• expected contribution to the load from each generator under design conditions, as a
percentage;
• nominal generator set run time under design conditions;
• system voltage;
• ratings of major components.
5.2 Power generation mix
5.2.1 General
Energy sources to be used in the micropower plant should be chosen on the basis of:
• assessment of affordable energy needs (see IEC TS 62257-2);
• quality of service as defined in the general specification (see IEC TS 62257-2:2015,
Annex C);
• capability of the different technologies to match the electrical needs, the affordable
services cost and the user’s preferences IEC TS 62257-2:2015, Annex D;
• local availability of energy sources (see IEC TS 62257-4);
• installed cost, maintenance costs and business plan of the project (see IEC TS 62257-
4:2015, Annex D);
• local regulations or constraints regarding use of the resource or installation of the
generator and associated equipment;
• aesthetic and environmental impacts.
The project implementer shall determine the proportion of power and energy to be provided by
the different energy sources.
NOTE See also the calculations of renewable energy fraction in Annex E.
In selecting renewable energy generators, the following additional factors shall be taken into
account:
• time and cost for obtaining reliable resource data;
• adequacy of the renewable resource based on measured or estimated data;

• where more than one renewable energy generator is used, the seasonal and short-term
complementarity of the energy sources.
Recommendations for the use of small renewable energy generators are provided in IEC
TS 62257-7.
The methodologies for assessing the renewable energy resources are provided in the specific
documents dedicated to each generation technology (see IEC TS 62257-7-3).
5.2.2 Internal combustion generator sets
Selection should be based on consideration of the following additional factors:
• estimated monthly run time;
• fuel costs;
• use of the fuel on site for other purposes;
• noise levels emitted by the set, and required noise levels for the installation.
Recommendations for the use of generator sets are provided in IEC TS 62257-7-3.
5.3 Electrical design
5.3.1 System voltage selection
5.3.1.1 Output voltage
The power system shall be able to provide the following low-voltage a.c. levels for 60 Hz or
50 Hz systems, as specified in IEC TS 62257-9-2:
• 240 V 1-Ø / 415 V 3-Ø;
• 230 V 1-Ø / 400 V 3-Ø;
• 220 V 1-Ø / 380 V 3-Ø;
• 120 V 1-Ø / 208 V 3-Ø;
• or obeyed by local code
or ELV d.c. levels, especially 12 V or 24 V as specified in IEC TS 62257-9-4.
Non-separated MPPTs connecting LV d.c. arrays to ELV d.c. battery banks are not allowed.
5.3.1.2 Internal voltages
Voltages at the output of generators or components may be different from the voltages at the
output of the power system.
The maximum levels of voltages shall be chosen in accordance with the maximum level of
skill of the local operating staff. Levels of skill are defined in IEC TS 62257-6.
The different voltage domains and the operation rules are also defined in IEC TS 62257-6. If
the local level skill is relatively low, it is recommended that the ELV domain be chosen.
Consideration should be given to the fact that many arrays are now using the a.c. bus
configuration or using MPPTs where the array is LV d.c. and that appropriate additional
training might be required to provided if the local skill level is low.

– 16 – IEC TS 62257-9-1:2016 © IEC 2016
5.3.2 Interconnection of generators
Several cases may be considered depending on the type of energy sources and the type of
application of equipment to be supplied. Where more than one generator is used, their outputs
may be connected in common at an a.c. or a d.c. bus. The following Figure 3 and Figure 4
provide examples of generators interconnection schemes.
DC DC
AC
G1 G2
G3
=
(if necessary)
=
DC bus
=
~
AC bus
IEC
G generator
Figure 3 – Interconnection configuration with d.c. bus and a.c. bus
DC DC
AC
G1 G2
G3
= =
~ ~
AC bus
IEC
Figure 4 – Interconnection configuration with a.c. bus only
Examples of architectures of complete systems are provided in IEC TS 62257-2:2015,
Annex E.
Attention shall be paid to the synchronization of a.c. generators which may be manual or
automatic. Generally it is the most powerful and the longest running time a.c. generator which
forms the grid and the other generators have to be synchronized with it when running.
5.4 Mechanical and civil works
5.4.1 Civil works
All structures shall be constructed to appropriate local statutory requirements and standards.
All civil works should be carried out in such a way as to minimize the environmental impacts,
especially with regard to soil erosion and damage to vegetation.
5.4.2 Technical room
Some equipment, such as energy management device, charge controller, energy converter,
main board, switches and protective devices as well as interconnection of the different circuits

shall be installed in a technical room. For small systems, this technical room may be a
cabinet.
This technical room shall be designed and installed in accordance with the requirements of
IEC TS 62257-5 and IEC TS 62257-6.
5.4.3 Battery room
Special requirements for the battery room are given in Annex D.
NOTE Methodology for the selection of batteries and batteries management systems for stand-alone
electrificati
...