IEC TS 62257-9-4:2016

Recommendations for renewable energy and hybrid systems for rural electrification - Part 9-4: Integrated systems - User installation

IEC TS 62257-9-4:2016(E) specifies the general requirements for the design and the implementation of a user's installation. It applies to single phase user's electrical installations with maximum power of 500 VA, in decentralized rural electrification systems. It is applicable to installations supplied by an AC microgrid and to installations encompassing their own single-unit AC micropower plant or DC micropower plant. The main technical changes with regard to the previous edition are as follows: changing the voltage range covered by the technical specification to AC nominal voltage below 1 000 V and DC nominal voltage below 1 500 V.
This publication is to be read in conjunction with IEC 62257 series.

General Information

• Status: Published
• Publication Date: 26-Sep-2016
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 27.160 - Solar energy engineering
• Technical Committee: TC 82 - Solar photovoltaic energy systems
• Drafting Committee: JWG 1 - TC 82/JWG 1
• Current Stage: PPUB - Publication issued
• Start Date: 15-Nov-2016
• Completion Date: 27-Sep-2016

Relations

• Revises: IEC TS 62257-9-4:2006 - Recommendations for small renewable energy and hybrid systems for rural electrification - Part 9-4: Integrated system - User installation
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC TS 62257-9-4 ®
Edition 2.0 2016-09
TECHNICAL
SPECIFICATION
colour
inside
Recommendations for renewable energy and hybrid systems for rural
electrification –
Part 9-4: Integrated systems – User installation

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IEC TS 62257-9-4 ®
Edition 2.0 2016-09
TECHNICAL
SPECIFICATION
colour
inside
Recommendations for renewable energy and hybrid systems for rural

electrification –
Part 9-4: Integrated systems – User installation

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.160 ISBN 978-2-8322-3588-1

– 2 – IEC TS 62257-9-4:2016 © IEC 2016
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative reference . 7
3 Terms and definitions . 8
4 General considerations . 9
4.1 General . 9
4.2 Installation limits . 9
4.3 User interface . 9
5 Protection against electric shock . 9
5.1 Requirements for d.c. parts of installation . 9
5.2 Requirements for a.c. parts of installation . 9
5.2.1 General . 9
5.2.2 Neutral earthing system . 9
6 Protection against overcurrent . 11
7 Protection against effect of lightning. 11
7.1 Installation supplied from a microgrid . 11
7.2 Standalone installation . 11
8 Selection and erection of electrical equipment . 12
8.1 Wiring system . 12
8.1.1 General . 12
8.1.2 Voltage drops . 12
8.1.3 Cross-sectional area of conductors . 12
8.1.4 Connections . 13
8.1.5 Installation method . 14
8.1.6 Selection and erection of wiring systems in relation to external
influences . 15
8.1.7 Specific rules to wiring systems buried in earth . 17
8.1.8 Circuits identification . 18
8.2 Isolation and switching . 18
8.2.1 Overcurrent protective devices . 18
8.2.2 Residual current devices . 18
8.3 Surge protective devices . 18
8.4 Earthing arrangement, protective conductors and protective bonding . 18
8.5 User interface . 18
9 Verification . 19
9.1 Pre-commissioning checks . 19
9.1.1 General information . 19
9.1.2 Verification by inspection . 19
9.1.3 Verification by tests . 20
10 Operation and maintenance . 20
Annex A (informative) Maximum possible length of circuits with different cables and
conductors to handle maximum voltage drops (ambient temperature 30 °C) . 21

Figure 1 – Installation limits . 9

Figure 2 – Protection of persons in an installation supplied from a microgrid according
to a TN-C-S system . 10
Figure 3 – Protection of persons in a combined d.c. and a.c. system . 11
Figure A.1 – Maximum possible length of circuit as a function of current for a voltage
drop of 3 % in a.c. system in a cable HO5VVF . 22
Figure A.2 – Maximum possible length of circuit as a function of current for a voltage
drop of 15 % in d.c. system in a cable 1000RO2V . 23

Table 1 – Maximum design current of circuits depending on voltages . 11
Table 2 – Maximum acceptable voltage drop values in installations . 12
Table 3 – Cross-sectional area for copper conductors in fixed installations . 13
Table 4 – Selection of wiring systems . 14
Table 5 – Installation of wiring systems . 14
Table 6 – Fuses/circuit breakers rating and selection for overcurrent protection . 18

– 4 – IEC TS 62257-9-4:2016 © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RECOMMENDATIONS FOR RENEWABLE ENERGY
AND HYBRID SYSTEMS FOR RURAL ELECTRIFICATION –

Part 9-4: Integrated systems – User installation

FOREWORD
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IEC 62257-9-4, 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
...