IEC TS 62257-9-3:2016

IEC TS 62257-9-3 ®
Edition 2.0 2016-09
TECHNICAL
SPECIFICATION
colour
inside
Recommendations for renewable energy and hybrid systems for rural
electrification –
Part 9-3: Integrated systems – User interface

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IEC TS 62257-9-3 ®
Edition 2.0 2016-09
TECHNICAL
SPECIFICATION
colour
inside
Recommendations for renewable energy and hybrid systems for rural

electrification –
Part 9-3: Integrated systems – User interface

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.160 ISBN 978-2-8322-3587-4

– 2 – IEC TS 62257-9-3:2016 © IEC 2016
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative reference . 6
3 Terms and definitions . 7
4 Electrical characteristics . 8
4.1 Equipment . 8
4.2 System voltages . 9
5 Functional description . 9
6 Design and erection . 10
6.1 System earthing . 10
6.2 Implementation of interface functions . 10
6.2.1 Function A: connection to electricity sources . 10
6.2.2 Function B: isolation . 10
6.2.3 Function C: protection against direct and indirect contact . 10
6.2.4 Function D: protection against overcurrents . 11
6.2.5 Function E: contract management . 11
6.2.6 Function F: earthing . 11
6.2.7 Function G: distribution of circuits . 11
6.3 Insulation requirements . 11
6.4 Selection of electrical equipment . 11
6.5 Housing . 11
6.6 Protection against fraudulent use. 11
7 Information to be given and marking . 12
8 Verification and acceptance . 12
8.1 General . 12
8.2 Verification by inspection . 12
8.3 Commissioning tests . 13

Figure 1 – General configuration of an electrification system . 6
Figure 2 – Interface for user installations supplied from an a.c. or a d.c. source . 9
Figure 3 – Interface for user installations supplied locally from a.c. or d.c. sources (not
from a microgrid) . 10

Table 1 – Functions ensured by various types of user interfaces . 9

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

Part 9-3: Integrated systems – User interface

FOREWORD
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The main task of IEC technical committees is to prepare International Standards. In
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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 62257-9-3, which is a technical specification, has been prepared by IEC technical
committee 82: Solar photovoltaic energy systems.

– 4 – IEC TS 62257-9-3:2016 © IEC 2016
This second edition cancels and replaces the first edition issued in 2006. It constitutes a
technical revision.
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).
• Deleted below 100 kVA from upper limit.
• Including 240 V and 220 V 1-Ø in the voltage levels (scope).
• Deleted the terms microgrid and micropowerplants from terms and definitions.
• Stated the requirement for segregation between a.c. and d.c circuits in housing (6.5).
• Stated that the protection devices for overcurrent are always accessible (6.6).
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
82/1030/DTS 82/1089/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 part of IEC 62257-9 is to be used in conjunction with the IEC 62257 series.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
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.

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INTRODUCTION
The IEC 62257 series intends to provide to 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 should 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
...