IEC TR 62102:2005

TECHNICAL IEC
REPORT TR 62102
Second edition
2005-05
Electrical safety –
Classification of interfaces for equipment
to be connected to information and
communications technology networks

Reference number
IEC/TR 62102:2005(E)
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TECHNICAL IEC
REPORT TR 62102
Second edition
2005-05
Electrical safety –
Classification of interfaces for equipment
to be connected to information and
communications technology networks

 IEC 2005  Copyright - all rights reserved
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– 2 – TR 62102  IEC:2005(E)
CONTENTS
FOREWORD.3
INTRODUCTION.5

1 Scope.6
2 Normative references.6
3 Terms and definitions .7
3.1 Definitions from IEC 60950-1 .7
3.2 Definitions from IEC 60950-21 .9
3.3 Additional definitions for this document .9
3.4 Abbreviations.10
4 Reference configuration.10
5 Safety categories of interfaces provided for connection to an information and
communications technology network .13
5.1 SELV circuits.13
5.2 TNV circuits.13
5.3 User information .13
5.4 RFT circuits.13
6 Phenomena affecting the safety of interface ports .13
6.1 Network Environment 0.14
6.2 Network Environment 1.14
7 Determination of circuit type.15

Annex A (informative) Consideration of interface phenomenon .16
Annex B (informative) Worked examples of certain network interfaces.19
Annex C (informative) Conditions for Network Environment 0.22
Annex D (informative) Voltage ranges of SELV circuits and TNV circuits.23

Bibliography .24

TR 62102  IEC:2005(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
ELECTRICAL SAFETY –
CLASSIFICATION OF INTERFACES FOR EQUIPMENT
TO BE CONNECTED TO INFORMATION AND
COMMUNICATIONS TECHNOLOGY 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
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The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC 62102, which is a technical report, was prepared by IEC technical committee 108: Safety
of electronic equipment within the field of audio/video, information technology and
communication technology, previously organized as IEC technical committee 74: Safety and
energy efficiency of IT equipment.
This second edition cancels and replaces the first edition published in 2001. This edition
constitutes a technical revision. The principal changes in this edition as compared with the first
edition of IEC 62102 are as follows (small changes are not listed):
− this 2nd edition was updated to accord with IEC 60950-1:2001;
− RFT (remote feeding telecommunication) circuits from IEC 60950-21 have been added;

– 4 – TR 62102  IEC:2005(E)
− in Annex B more interfaces have been added;
− in Annex B the category of xDSL interfaces have replaced ADSL interfaces.
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
108/128/DTR 108/130/RVC
Full information on the voting for the approval of this technical report 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.
Terms printed in bold in the text are defined in Clause 3.
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
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this document may be published at a later date.

TR 62102  IEC:2005(E) – 5 –
INTRODUCTION
This technical report is a guide to the determination of the interface requirements for
equipment in terms of safety. It lists a number of interfaces and indicates the safety category of
each listed interface. This technical report does not contain sufficient detail for conformance
testing purposes, except when used in conjunction with product standards such as
IEC 60950-1 and IEC 60950-21.
The equipment safety standards IEC 60950-1 and IEC 60950-21 specify the requirements for
categories of circuits as SELV circuits, TNV circuits, RFT circuits and hazardous voltage
circuits (among others). For stand-alone equipment it is a relatively simple matter to determine
the different categories of circuits. However, an equipment which has data port interfaces is
intended to be connected to other equipment, either locally or via a network. In this case, the
safety categories of the interfaces which will be connected together have to be compatible with
each other. Furthermore, the category of the interface of the remote equipment may be
unknown. This is the case in systems where telecommunication equipment and data
processing equipment are connected together via different types of interfaces and networks.
To overcome this situation it is necessary to classify the interfaces of equipment in such
configurations according to the application and to select the safety category for the interfaces
of the equipment and for the type of the network. Similarly, the interfaces have to be classified
for protection against damage of the equipment and of the network. Aspects of protection are
dealt with in the ITU-T K series of recommendations.

– 6 – TR 62102  IEC:2005(E)
ELECTRICAL SAFETY –
CLASSIFICATION OF INTERFACES FOR EQUIPMENT
TO BE CONNECTED TO INFORMATION AND
COMMUNICATIONS TECHNOLOGY NETWORKS

1 Scope
This technical report applies to equipment interfaces. These interfaces within the equipment
may be connected to telecommunication networks, may form part of the telecommunication
network infrastructure or may provide localized transfer of data. This technical report provides
guidance on the classification of interfaces in accordance with the circuit types defined in
IEC 60950-1 and IEC 60950-21 following an analysis of the telecommunication network
characteristics.
This technical report only covers equipment appropriately interconnected. Furthermore, it does
not address damage caused by one equipment to another equipment to which it is connected.
Exceptionally, interfaces may be designed for higher or lower levels for special applications. In
such cases it should be ensured that only interfaces having the same safety category and
protection level are connected together. This is based on the available specifications of the
equipment manufacturers and network providers, and on information regarding the installation
category of the mains interface.
This technical report is intended to be used by equipment designers, network operators,
network regulators/authorities, standards writers and network installers. It is applicable to
various interfaces of equipment. Network
...