IEC TS 62257-9-3:2006

IEC/TS 62257-9-3 ®
Edition 1.0 2006-10
TECHNICAL
SPECIFICATION
colour
inside
Recommendations for small renewable energy and hybrid systems for rural
electrification –
Part 9-3: Integrated system – User interface

IEC/TS 62257-9-3:2006(E)
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IEC/TS 62257-9-3 ®
Edition 1.0 2006-10
TECHNICAL
SPECIFICATION
colour
inside
Recommendations for small renewable energy and hybrid systems for rural
electrification –
Part 9-3: Integrated system – User interface

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
M
ICS 27.160; 27.180 ISBN 2-8318-8864-6

– 2 – TS 62257-9-3 © IEC:2006(E)

CONTENTS
FOREWORD.3
INTRODUCTION.5

1 Scope.6
2 Normative reference .6
3 Terms and definitions .7
4 Electrical characteristics.9
4.1 Equipment.9
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
6.3 Insulation requirements .11
6.4 Selection of electrical equipment .11
6.5 Housing.11
6.6 Protection against fraudulent use .12
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 a 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

TS 62257-9-3 © IEC:2006(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RECOMMENDATIONS FOR SMALL RENEWABLE ENERGY
AND HYBRID SYSTEMS FOR RURAL ELECTRIFICATION –

Part 9-3: Integrated system – 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.
This part of IEC 62257-9 is based on IEC/PAS 62111 (1999); it cancels and replaces the
relevant parts of IEC/PAS 62111.

– 4 – TS 62257-9-3 © IEC:2006(E)

This part of IEC 62257-9 is to be used in conjunction with the IEC 62257 series.
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
82/413/DTS 82/440/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 publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 62257 series, under the general title Recommendations for small
renewable energy and hybrid systems for rural electrification, can be found on the IEC
website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site 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 publication using a colour printer.

TS 62257-9-3 © IEC:2006(E) – 5 –
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 500 V, d.c. nominal voltage below 750 V and nominal power below 100 kVA.
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
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.

– 6 – TS 62257-9-3 © IEC:2006(E)

RECOMMENDATIONS FOR SMALL RENEWABLE ENERGY
AND HYBRID SYSTEMS FOR RURAL ELECTRIFICATION –

Part 9-3: Integrated system – User interface

1 Scope
The purpose of this part of IEC 62257 is to specify the general requirements for the design
and the implementation of the interface equipment within the user’s installation which
connects to a microgrid or the gen
...