IEC 63044-3:2017

IEC 63044-3 ®
Edition 1.1 2021-05
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
colour
inside
Home and building electronic systems (HBES) and building automation and
control systems (BACS) –
Part 3: Electrical safety requirements

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IEC 63044-3 ®
Edition 1.1 2021-05
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
colour
inside
Home and building electronic systems (HBES) and building automation and

control systems (BACS) –
Part 3: Electrical safety requirements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.120.01; 29.120.99 ISBN 978-2-8322-9781-0

IEC 63044-3 ®
Edition 1.1 2021-05
CONSOLIDATED VERSION
REDLINE VERSION
colour
inside
Home and building electronic systems (HBES) and building automation and
control systems (BACS) –
Part 3: Electrical safety requirements

– 2 – IEC 63044-3:2017+AMD1:2021 CSV
© IEC 2021
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 7
3.1 Terms and definitions . 7
3.2 Abbreviated terms . 10
4 Classification of HBES/BACS network interfaces Void . 10
5 Safety requirements and compliance criteria. 10
6 Requirements . 11
6.1 General . 11
6.2 Classification requirements of installation areas . 11
6.2.1 Overvoltage category . 11
6.2.2 Pollution degree . 11
6.2.3 Material class . 11
6.3 Electrical safety requirements . 11
6.3.1 Protection from hazards in the device . 11
6.3.2 Protection from overvoltage on the network and from hazards caused by
different types of of circuit network . 12
6.3.3 Protection from touch current . 14
6.3.4 Protection of the communication wiring from overheating . 16
6.4 Installation . 16
Annex A (informative) List of product standards for electrical safety . 17
Bibliography . 19

Table 1 – Requirements for connection of devices to a dedicated HBES/BACS network. 12

© IEC 2021
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HOME AND BUILDING ELECTRONIC SYSTEMS (HBES) AND
BUILDING AUTOMATION AND CONTROL SYSTEMS (BACS) –

Part 3: Electrical safety requirements

FOREWORD
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
This consolidated version of the official IEC Standard and its amendment has been
prepared for user convenience.
IEC 63044-3 edition 1.1 contains the first edition (2017-01) [documents 23/735/CDV and
23/747/RVC] and its amendment 1 (2021-05) [documents 23/912/CDV and 23/961A/RVC].
In this Redline version, a vertical line in the margin shows where the technical content
is modified by amendment 1. Additions are in green text, deletions are in strikethrough
red text. A separate Final version with all changes accepted is available in this
publication.
– 4 – IEC 63044-3:2017+AMD1:2021 CSV
© IEC 2021
International Standard IEC 63044-3 has been prepared by IEC technical committee 23:
Electrical accessories.
A list of all parts in the IEC 63044 series, published under the general title Home and Building
Electronic Systems (HBES) and Building Automation Control Systems (BACS), can be found
on the IEC website.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
In this publication, the following print types are used:
– Requirements proper: in roman type.
– Test specifications: in italic type.
This document shall be used in conjunction with relevant product safety standards.
The committee has decided that the contents of the base publication and its amendment will
remain unchanged until the stability 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
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
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.
© IEC 2021
INTRODUCTION
The IEC 63044 series deals with developing and testing Home and Building Electronic
Systems (HBES) and Building Automation and Control Systems (BACS).
This document deals with electrical safety requirements for HBES/BACS.
This document is based on the philosophy that a device considered electrically safe according
to an appropriate product safety standard should also remain safe when connected to a
network. This document specifies in addition to the specific product standard the electrical
safety requirements necessary in order for an HBES/BACS device connected to a network to
remain safe under normal and single-fault conditions of the HBES/BACS network and at the
same time under normal and single-fault conditions of one or more HBES/BACS devices
connected to the HBES/BACS network. This includes protection from overvoltages on the
network, protection from hazards caused by connection of different types of circuit network,
the limitation of the touch current to a network and protection of the communication wiring
from overheating.
The HBES/BACS network is any interconnection between HBES/BACS products devices. The
HBES/BACS networks can be either an ICT network with interfaces classified according to
IEC 62949 or a dedicated network classified as a mains, ELV, FELV, SELV or PELV circuit
network.
For HBES/BACS products devices connected to an ICT network, the requirements in
IEC 62949 apply.
For HBES/BACS products devices connected to a dedicated HBES/BACS network, the
requirements for the electrical separation between the device and the network circuit are
specified (see Table 1). These specifications of the electrical separations follow the principle
in the basic safety publications IEC 60664-1 and IEC 61140, together with the installation
requirements of IEC 60364. The following compromises are used.
– According to the principles of IEC 60664-1, the rated impulse voltage for the separation
shall be the higher of the impulse voltage on the network and the rated impulse voltage of
the device circuit to be connected to the network.
– The overvoltage categories considered by IEC 60664-1 refer to overvoltages derived
directly from the mains through the power supply.
– The overvoltages coming from other sources (e.g. capacitive couplings) are not specified
in IEC 60664-1. IEC 60664-1 recommends that technical committees specify overvoltage
categories or rated impulse voltages as appropriate.
For the purposes of this document, the following impulse voltages have been specified.
• For networks with galvanic electrical separation f
...