Particular safety requirements for equipment to be connected to information and communication technology networks

IEC 62949:2017 applies to the interface of equipment designed and intended to be connected as a communication terminal to an information and communication technology (ICT) network termination.
This document does not apply to:
- equipment covered by IEC 62368-1; or
- interfaces to other networks.
This document specifies the safety requirements of the interface to the ICT network only. Requirements additional to those specified in this document may be necessary for equipment intended for operation while exposed, for example, to extremes of temperature, to excessive dust, moisture, or vibration, to flammable gases, to corrosive or explosive atmospheres and electro medical applications with physical connections to the patient. The following requirements are not covered by this document:
- functional safety of equipment;
- functional reliability of equipment;
- communication facilities with remote supply using hazardous voltage;
- protection of equipment connected to ICT networks from functional damage.

Exigences de sécurité spécifiques pour les équipements destinés à être connectés aux réseaux d'information et de communication

IEC 62949:2017 s’applique à l’interface de l’équipement conçu et prévu pour être connecté en tant que terminal de communication à une terminaison de réseau des technologies de l’information et de la communication (TIC). Le présent document ne s’applique pas:
- aux équipements couverts par l’IEC 62368-1; et
- aux interfaces connectées à d’autres réseaux. Le présent document spécifie les exigences de sécurité de l’interface au réseau des TIC. Des exigences venant s’ajouter à celles spécifiées dans le présent document peuvent être nécessaires pour les équipements destinés à fonctionner en étant exposés, par exemple, à des températures extrêmes, à une poussière, une humidité ou une vibration excessive, à des gaz inflammables ou à des atmosphères corrosives ou explosives, les applications électromédicales connectées physiquement au patient. Les exigences suivantes ne sont pas couvertes par le présent document:
- la sécurité fonctionnelle des équipements;
- la fiabilité fonctionnelle des équipements;
- les installations de communications avec une alimentation à distance utilisant une tension dangereuse;
- la protection des équipements connectés aux réseaux des TIC contre les dommages fonctionnels.
Mots clés: audio/vidéo, terminal de communication, réseau des TIC, circuits externes

General Information

Status
Published
Publication Date
19-Jan-2017
Current Stage
PPUB - Publication issued
Completion Date
20-Jan-2017
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IEC 62949
Edition 1.0 2017-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Particular safety requirements for equipment to be connected to information
and communication networks
Exigences de sécurité spécifiques pour les équipements destinés à être
connectés aux réseaux d’information et de communication
IEC 62949:2017-01(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 62949
Edition 1.0 2017-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Particular safety requirements for equipment to be connected to information
and communication networks
Exigences de sécurité spécifiques pour les équipements destinés à être
connectés aux réseaux d’information et de communication
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.160; 35.020 ISBN 978-2-8322-3790-8

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 62949:2017 © IEC 2017
CONTENTS

FOREWORD ........................................................................................................................... 4

INTRODUCTION ..................................................................................................................... 6

1 Scope .............................................................................................................................. 7

2 Normative references ...................................................................................................... 7

3 Terms and definitions ...................................................................................................... 7

4 Safety requirements and compliance criteria.................................................................... 8

4.1 General ................................................................................................................... 8

4.2 Interconnection of equipment .................................................................................. 9

4.2.1 General requirements ...................................................................................... 9

4.2.2 Types of interconnection circuits ...................................................................... 9

4.3 ES1 circuits ............................................................................................................ 9

4.3.1 Limits .............................................................................................................. 9

4.3.2 Protection against contact with ES1 circuits ..................................................... 9

4.4 ES2 circuits ............................................................................................................ 9

4.4.1 Limits .............................................................................................................. 9

4.4.2 Protection against contact with ES2 circuits ..................................................... 9

4.5 ES3 circuits ............................................................................................................ 9

4.5.1 Limits .............................................................................................................. 9

4.5.2 Protection against contact with ES3 circuits ..................................................... 9

4.6 Protection from hazards in the equipment for persons servicing ICT networks,

and users of other equipment connected to the network ........................................ 10

4.6.1 Protection from ES3....................................................................................... 10

4.6.2 Separation of the ICT network from earth ...................................................... 10

4.6.3 Touch current to ICT networks ....................................................................... 10

4.6.4 Summation of touch currents from ICT networks ............................................ 10

4.7 Protection of equipment users from overvoltages on ICT networks ........................ 10

4.8 Protection of the wiring system of an ICT network from overheating ...................... 10

Annex A (informative) Relevant safety standards for the application of this document .......... 11

Annex B (informative) ICT network voltages and signals ...................................................... 12

B.1 General ................................................................................................................. 12

B.2 Contact with operating voltages on ICT networks .................................................. 13

Annex C (informative) Comparison of terms and definitions introduced in this

document .............................................................................................................................. 15

C.1 General ................................................................................................................. 15

C.2 Comparison of terms and definitions ..................................................................... 15

Annex D (informative) Overview of networks ........................................................................ 22

Bibliography .......................................................................................................................... 23

Figure B.1 – Current limit curves ........................................................................................... 13

Figure D.1 – Overview of network ......................................................................................... 22

---------------------- Page: 4 ----------------------
IEC 62949:2017 © IEC 2017 – 3 –
Table C.1 – Comparison of terms and definitions in IEC 60950-1:2005 and

IEC 62368-1:2014 ................................................................................................................. 16

Table C.2 – Comparison of terms and definitions in IEC 62151:2000 and IEC 62368-

1:2014 .................................................................................................................................. 19

---------------------- Page: 5 ----------------------
– 4 – IEC 62949:2017 © IEC 2017
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PARTICULAR SAFETY REQUIREMENTS FOR EQUIPMENT TO BE
CONNECTED TO INFORMATION AND COMMUNICATION NETWORKS
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

this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,

Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC

Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested

in the subject dealt with may participate in this preparatory work. International, governmental and non-

governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely

with the International Organization for Standardization (ISO) in accordance with conditions determined by

agreement between the two organizations.

2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

consensus of opinion on the relevant subjects since each technical committee has representation from all

interested IEC National Committees.

3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

misinterpretation by any end user.

4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

transparently to the maximum extent possible in their national and regional publications. Any divergence

between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in

the latter.

5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

6) All users should ensure that they have the latest edition of this publication.

7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

members of its technical committees and IEC National Committees for any personal injury, property damage or

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

Publications.

8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.

9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of

patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 62949 has been prepared by IEC technical committee 108: Safety

of electronic equipment within the field of audio/video, information technology and

communication technology.
The text of this standard is based on the following documents:
FDIS Report on voting
108/664/FDIS 108/676/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.

In this standard, the following print types are used:
• requirements proper and normative annexes: in roman type;
---------------------- Page: 6 ----------------------
IEC 62949:2017 © IEC 2017 – 5 –
• compliance statements and test specifications: in italic type;
• notes and other informative matter: in smaller roman type;
• normative conditions within tables: in smaller roman type;
• Terms that are defined in Clause 3: bold.

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.

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.
---------------------- Page: 7 ----------------------
– 6 – IEC 62949:2017 © IEC 2017
INTRODUCTION

This document is applicable for products intended to be connected as communication

terminal to an ICT network not covered by the scope of IEC 62368-1. It is to be used in

conjunction with other product safety standards, examples of which are listed in Annex A.

This document, in accordance with the 'principles of safety' given in the introduction of

IEC 62368-1, covers the requirements and compliance criteria under three headings.

• Protection of equipment users from hazards in the equipment. The users are considered to

be protected from hazards in the equipment if the equipment complies with a relevant

safety standard, for example one of those listed in Annex A, but compliance with those

standards is not part of this document.
NOTE An equipment user could be an ordinary person or an instructed person.

• Protection of skilled persons or instructed persons working on an ICT network and

other users of an ICT network, from hazardous conditions on an ICT network resulting

from the connection of the equipment.
• Protection of equipment users from voltages on an ICT network.

Upper limits for ICT networks signals have been defined. They include also telephone ringing

signals which have been defined taking into account voltages commonly used in the different

networks. The electrical hazard criteria have been chosen to be in accordance with

IEC TS 60479 (all parts).

Test levels used for the equipment take account of the possibility that overvoltages may occur

on ICT networks. Special consideration has been given to equipment parts expected to be

held or touched during normal use, e.g. telephone handsets.

It is recognised that in high overvoltages risk areas, requirements of this document may not

be sufficient. Additional protective devices, not covered by this document, may be installed in

the ICT networks to better meet extreme conditions.

A comparison of terms introduced in this document with existing IEC standards is given in

Annex C.
---------------------- Page: 8 ----------------------
IEC 62949:2017 © IEC 2017 – 7 –
PARTICULAR SAFETY REQUIREMENTS FOR EQUIPMENT TO BE
CONNECTED TO INFORMATION AND COMMUNICATION NETWORKS
1 Scope

This document applies to the interface of equipment designed and intended to be connected

as a communication terminal to an information and communication technology (ICT)
network termination.
This document does not apply to:
• equipment covered by IEC 62368-1; and
• interfaces to other networks.

NOTE 1 An example of ‘other networks’ is a dedicated Home and Building Electronic Systems/Building

Automation and Control Systems HBES/BACS network covered by EN 50491-3.

This document specifies the safety requirements of the interface to the ICT network only.

NOTE 2 See Annex D.
Requirements additional to those specified in this document may be necessary for

• equipment intended for operation while exposed, for example, to extremes of temperature,

to excessive dust, moisture, or vibration, to flammable gases, to corrosive or explosive

atmospheres,
• electro medical applications with physical connections to the patient.
The following requirements are not covered by this document:
• functional safety of equipment;
• functional reliability of equipment;
• communication facilities with remote supply using hazardous voltage;
• protection of equipment connected to ICT networks from functional damage.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their

content constitutes requirements of this document. For dated references, only the edition

cited applies. For undated references, the latest edition of the referenced document (including

any amendments) applies.

NOTE Lists of other related documents can be found in Annex A and in the Bibliography.

IEC 62368-1:2014, Audio/video, information and communication technology equipment –

Part 1: Safety requirements
3 Terms and definitions

For the purposes of this document, the terms and definitions given in IEC 62368-1and the

following apply.
---------------------- Page: 9 ----------------------
– 8 – IEC 62949:2017 © IEC 2017

ISO and IEC maintain terminological databases for use in standardization at the following

addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
NOTE Defined terms are printed in bold.
3.1
information and communication technology network
ICT network

metallically terminated transmission medium consisting of paired conductors intended for

communication between equipment that may be located in separate buildings, excluding:

• the mains system for supply, transmission and distribution of electrical power, if used as a

communication transmission medium;
• a dedicated HBES/BACS networks;

• external circuits operating at ES1 levels connecting units of audio/video, information and

communication technology equipment

Note 1 to entry: This network may include twisted pairs, and may include circuits, which are subjected to

transients as indicated in Table 14 of IEC 62368-1:2014, ID1 (assumed to be 1,5 kV).

Note 2 to entry: An ICT network may be:
• public or privately owned;

• subject to longitudinal (common mode) voltages induced from nearby power lines or electric traction lines.

Note 3 to entry: Examples of ICT networks are:
• a public switched telephone network;
• a public data network;
• an Integrated Services Digital Network (ISDN);

• a private network with electrical interface characteristics similar to the above.

Note 4 to entry: For information about circuit voltages and signals, which may be present, see Annex B.

3.2
communication terminal
equipment connected to an ICT network to provide access to one or more specific
information transfer services

Note 1 to entry: A communication terminal may be characterized, for example, as a user's communication

terminal, a communication terminal providing services, a communication terminal acting as an interface between

ICT networks.

Note 2 to entry: A communication terminal may have to translate the signals received from or sent to the

network according to the service considered.
4 Safety requirements and compliance criteria
4.1 General

It is assumed that adequate measures according to ITU-T Recommendation K.11 have been

taken to reduce the likelihood that the overvoltages presented to the equipment from the ICT

network exceed 1,5 kV peak. In installations where overvoltages presented to the equipment

may exceed 1,5 kV peak, additional measures such as surge suppression may be necessary.

The general conditions for tests of Annex B of IEC 62368-1:2014 apply, unless specified in

the relevant product safety standard.
---------------------- Page: 10 ----------------------
IEC 62949:2017 © IEC 2017 – 9 –

The references to the requirements of 4.4.4.5, 5.4.2.6 and 5.4.3.2 of IEC 62368-1:2014, may

be replaced by the corresponding requirements in other relevant safety standards listed in

Annex A, if the equipment is designed to comply with one of these standards.
4.2 Interconnection of equipment
4.2.1 General requirements

Where an equipment is intended to be electrically connected to another equipment via an ICT

network, interconnection circuits shall be selected to provide continued conformance to the

requirements of 5.2 of IEC 62368-1:2014 for ES1 or ES2 circuits, after making connections.

NOTE This is normally achieved by connecting ES2 circuits to ES2 circuits and ES1circuits to ES1 circuits.

4.2.2 Types of interconnection circuits

Interconnection circuits to ICT networks shall be ES1 circuits or ES2 circuits according to 5.2

of IEC 62368-1:2014.
4.3 ES1 circuits
4.3.1 Limits
The limits of 5.2.1 of IEC 62368-1:2014 for ES1 apply.
4.3.2 Protection against contact with ES1 circuits
There is no protection required for ES1 circuits.
4.4 ES2 circuits
4.4.1 Limits
The limits of 5.2.2 of IEC 62368-1:2014 for ES2 apply.
4.4.2 Protection against contact with ES2 circuits

For ES2 circuits, the requirements of 5.3.1 and 5.3.2.1 of IEC 62368-1:2014 apply for an

ordinary person and an instructed person.

For ES2 circuits, the requirements of 5.3.1 of IEC 62368-1:2014 apply for a skilled person.

4.5 ES3 circuits
4.5.1 Limits
The limits of 5.2.2 of IEC 62368-1:2014 for ES3 apply.
4.5.2 Protection against contact with ES3 circuits

For ES3 circuits, the requirements of 5.3.2.1 of IEC 62368-1:2014 apply for an ordinary

person and an instructed person.

For ES3 circuits, the requirements of 5.3.1 of IEC 62368-1:2014 apply for a skilled person.

---------------------- Page: 11 ----------------------
– 10 – IEC 62949:2017 © IEC 2017
4.6 Protection from hazards in the equipment for persons servicing ICT networks,
and users of other equipment connected to the network
4.6.1 Protection from ES3
Subclause 5.7.6.2 of IEC 62368-1:2014 applies.
4.6.2 Separation of the ICT network from earth
Subclause 5.4.11 of IEC 62368-1:2014 applies.
4.6.3 Touch current to ICT networks
Subclause 5.7.6.2 of IEC 62368-1:2014 applies.
4.6.4 Summation of touch currents from ICT networks
Subclause 5.7.7 of IEC 62368-1:2014 applies.
4.7 Protection of equipment users from overvoltages on ICT networks
Subclause 5.4.10 of IEC 62368-1:2014 applies.
4.8 Protection of the wiring system of an ICT network from overheating
Subclause 6.5.3 of IEC 62368-1:2014 applies.
---------------------- Page: 12 ----------------------
IEC 62949:2017 © IEC 2017 – 11 –
Annex A
(informative)
Relevant safety standards for the application of this document

This annex lists some examples of IEC product safety standards with which this document

may be used.
Publication Title

IEC 60601-1 (all parts) Medical electrical equipment – Part 1: General requirements for basic safety and

essential performance

IEC 61010 (all parts) Safety requirements for electrical equipment for measurement, control, and laboratory

use

IEC 62504:2014 General lighting – Light emitting diode (LED) products and related equipment – Terms

and definitions
---------------------- Page: 13 ----------------------
– 12 – IEC 62949:2017 © IEC 2017
Annex B
(informative)
ICT network voltages and signals
B.1 General

Certain voltages within ICT networks often exceed the steady state, safe to touch limits set

within general safety standards.

NOTE Years of practical experience by world-wide network operators have found ringing and other operating

voltages to be electrically safe. Records of accident statistics indicate that electrical injuries are not caused by

operating voltages.

Access to connectors carrying such signals with the standard test finger is permitted, provided

that inadvertent access is unlikely. The likelihood of inadvertent access is limited by

forbidding access with the test probe (Figure V.3 of IEC 62368-1:2014) which has a 6 mm

radius tip.
This requirement ensures that:

a) contact by a large part of the human body, such as the back of the hand, is impossible;

b) contact is possible only by deliberately inserting a small part of the body, less than 12 mm

across, such as a fingertip, which presents a high impedance;
c) the possibility of being unable to let-go the part in contact does not arise.

This applies both to contact with signals arriving from the network and to signals generated

internally in the equipment.

Ventricular fibrillation of the heart is considered to be the main cause of death by electric

shock.
of Figure B.1 (curve c of Figure 20 of IEC TS 60479-1:2005) is the threshold of
Curve c
1 1

ventricular fibrillation. The point 500 mA/100 ms has been found to correspond to a fibrillation

probability of the order of 0,14 %. Curve b on Figure B.1 (curve b of Figure 20 of

IEC TS 60479-1:2005) may be described as the 'let-go' limit curve. Some experts consider

curve c to be the appropriate limit for safe design, but use of this curve shall be considered

as an absolute limit.
---------------------- Page: 14 ----------------------
IEC 62949:2017 © IEC 2017 – 13 –
Curve b’
at 16 mA
10 000
a b
c c c
1 2 3
5 000
AC-4.1
AC-4.2
2 000
AC-4.3
1 000
500
AC-1 AC-2 AC-3 AC-4
200
100
0,1 0,2 0,5 1 2 5 10 20 50 100 200 500 2 000 10 000
1 000 5 000
Body current I , mA
IEC
Figure B.1 – Current limit curves
B.2 Contact with operating voltages on ICT networks

Total body impedance consists of two parts, the internal body resistance of blood and tissue

and the skin impedance. Operation voltages on ICT networks hardly reach the level where

skin impedance begins to rapidly decrease due to breakdown. The skin impedance is high at

low voltages, its value varying widely. The effects of skin c
...

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