IEC 60364-7-704:2017

IEC 60364-7-704 ®
Edition 3.0 2017-03
INTERNATIONAL
STANDARD
Low voltage electrical installations –
Part 7-704: Requirements for special installations or locations – Construction
and demolition site installations

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IEC 60364-7-704 ®
Edition 3.0 2017-03
INTERNATIONAL
STANDARD
Low voltage electrical installations –

Part 7-704: Requirements for special installations or locations – Construction

and demolition site installations

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.020; 91.140.50 ISBN 978-2-8322-4020-5

– 2 – IEC 60364-7-704:2017 © IEC 2017
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
704 Construction and demolition site installations . 6
704.1 Scope . 6
704.2 Normative references . 6
704.3 Terms and definitions . 7
704.30 Assessment of general characteristics . 7
704.31 Purposes, supplies and structure . 7
704.313 Supplies . 7
704.4 Protection for safety . 7
704.41 Protection against electric shock . 7
704.410 Introduction . 7
704.411 Protective measure: automatic disconnection of supply . 8
704.414 Protective measure: Extra-low voltage provided by SELV and PELV . 8
704.44 Protection against voltage disturbances and electromagnetic
disturbances . 8
704.443 Protection against transient overvoltages of atmospheric origin or due to
switching . 8
704.5 Selection and erection of equipment . 8
704.51 Common rules . 8
704.511 Compliance with standards. 8
704.512 Operational conditions and external influences . 9
704.52 Wiring systems . 9
704.53 Isolation, switching and control . 9
704.536 Isolation and switching . 9
704.56 Safety services . 10
704.6 Verification . 10
Annex A (informative) List of notes concerning certain countries . 11
Bibliography . 15

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW VOLTAGE ELECTRICAL INSTALLATIONS –

Part 7-704: Requirements for special installations or locations –
Construction and demolition site installations

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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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60364-7-704 has been prepared by IEC technical committee 64:
Electrical installations and protection against electric shock.
This third edition cancels and replaces the second edition published in 2005. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) clarification of the Scope;
b) clarification of compliance with standards;
c) clarification of devices for isolation.

– 4 – IEC 60364-7-704:2017 © IEC 2017
The text of this International Standard is based on the following documents:
FDIS Report on voting
64/2155/FDIS 64/2167/RVD
Full information on the voting for the approval of this International Standard 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.
A list of all parts in the IEC 60364 series, published under the general title Low-voltage
electrical installations, can be found on the IEC website.
The reader's attention is drawn to the fact that Annex A lists all of the “in-some-countries”
clauses on differing practices of a less permanent nature relating to the subject of this
standard.
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.
A bilingual version of this publication may be issued at a later date.

INTRODUCTION
For the purpose of this part of IEC 60364 (IEC 60364-7-704) the requirements of the general
parts 1 to 6 of IEC 60364 apply.
The IEC 60364-7-7XX parts of IEC 60364 contain particular requirements for special
installations or locations which are based on the requirements of the general parts of
IEC 60364 (IEC 60364-1 to IEC 60364-6). These IEC 60364-7-7XX parts are considered in
conjunction with the requirements of the general parts.
The particular requirements of this part of IEC 60364 supplement, modify or replace certain of
the requirements of the general parts of IEC 60364 being valid at the time of publication of
this part. The absence of reference to the exclusion of a part or a clause of a general part
means that the corresponding clauses of the general part are applicable (undated reference).
Requirements of other 7XX parts being relevant for installations covered by this part also
apply. This part may therefore also supplement, modify or replace certain of these
requirements valid at the time of publication of this part.
The clause numbering of this part follows the pattern and corresponding references of
IEC 60364. The numbers following the particular number of this part are those of the
corresponding parts, or clauses of the other parts of the IEC 60364 series, valid at the time of
publication of this part, as indicated in the normative references of this document (dated
reference).
If requirements or explanations additional to those of the other parts of the IEC 60364 series
are needed, the numbering of such items appears as 704.101, 704.102, 704.103 etc.
In the case where new or amended general parts with modified numbering were published
after this part was issued, the clause numbers referring to a general part in this 704 part may
no longer align with the latest edition of the general part. Dated references should be
observed.
– 6 – IEC 60364-7-704:2017 © IEC 2017
LOW VOLTAGE ELECTRICAL INSTALLATIONS –

Part 7-704: Requirements for special installations or locations –
Construction and demolition site installations

704 Construction and demolition site installations
704.1 Scope
The requirements of this part of IEC 60364 apply to installations for construction and
demolition sites for use during the period of the construction or demolition work which are
intended to be taken out of service upon completi
...