IEC TR 62368-2:2019

Audio/video, information and communication technology equipment - Part 2: Explanatory information related to IEC 62368-1:2018

IEC TR 62368-2:2019

Name:IEC TR 62368-2:2019   Standard name:Audio/video, information and communication technology equipment - Part 2: Explanatory information related to IEC 62368-1:2018
Standard number:IEC TR 62368-2:2019   language:English language
Release Date:06-May-2019   technical committee:TC 108 - Safety of electronic equipment within the field of audio/video, information technology and communication technology
Drafting committee:WG HBSDT - TC 108/WG HBSDT   ICS number:01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION

IEC TR 62368-2
Edition 3.0 2019-05
REDLINE VERSION
TECHNICAL
REPORT
colour
inside
Audio/video, information and communication technology equipment –
Part 2: Explanatory information related to IEC 62368-1:20142018





your local IEC member National Committee for further information.

IEC Central Office Tel.: +41 22 919 02 11
3, rue de
CH-1211 Geneva 20
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
details all new publications released. Available online and 67 000 electrotechnical terminology entries in English and
once a month by email. French extracted from the Terms and Definitions clause of
IEC publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or CISPR.

need further assistance, please contact the Customer Service

.
IEC TR 62368-2
Edition 3.0 2019-05
REDLINE VERSION
TECHNICAL
REPORT
colour
inside
Audio/video, information and communication technology equipment –

Part 2: Explanatory information related to IEC 62368-1: 20142018

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.160.01; 35.020 ISBN 978-2-8322-6916-9

– 2 – IEC TR 62368-2:2019 RLV © IEC 2019
CONTENTS
FOREWORD . 6
INTRODUCTION . 9
0 Principles of this product safety standard . 10
1 Scope . 12
2 Normative references . 13
3 Terms, definitions and abbreviations . 13
4 General requirements . 16
5 Electrically-caused injury . 23
6 Electrically-caused fire . 73
7 Injury caused by hazardous substances. 108
8 Mechanically-caused injury . 112
9 Thermal burn injury. 120
10 Radiation . 129
Annex A Examples of equipment within the scope of this standard . 136
Annex B Normal operating condition tests, abnormal operating condition tests .
and single fault condition tests . 137
Annex C UV Radiation . 140
Annex D Test generators . 140
Annex E Test conditions for equipment containing audio amplifiers . 140
Annex F Equipment markings, instructions, and instructional safeguards . 141
Annex G Components . 142
Annex H Criteria for telephone ringing signals . 150
Annex J Insulated winding wires for use without interleaved insulation . 152
Annex K Safety interlocks . 152
Annex L Disconnect devices . 152
Annex M Equipment containing batteries and their protection circuits . 153
Annex O Measurement of creepage distances and clearances . 162
Annex P Safeguards against conductive objects . 162
Annex Q Circuits intended for interconnection with building wiring . 163
Annex R Limited short-circuit test . 164
Annex S Tests for resistance to heat and fire . 164
Annex T Mechanical strength tests . 166
Annex U Mechanical strength of CRTs and protection against the effects of
implosion . 167
Annex V Determination of accessible parts . 167
Annex X Alternative method for determing clearances for insulation in circuits
connected to an AC mains not exceeding 420 V peak (300 V RMS) . 168
Annex Y Construction requirements for outdoor enclosures . 168
Annex A (informative) Background information related to the use of SPDs . 171
Annex B (informative) Background information related to measurement of discharges
– Determining the R-C discharge time constant for X- and Y-capacitors . 185
Annex C (informative) Background information related to resistance to candle flame
ignition . 196

Bibliography . 197

Figure 1 – Risk reduction as given in ISO/IEC Guide 51. 11
Figure 2 – HBSE Process Chart . 12
Figure 3 – Protective bonding conductor as part of a safeguard . 15
Figure 4 – Safeguards for protecting an ordinary person . 19
Figure 5 – Safeguards for protecting an instructed person . 20
Figure 6 – Safeguards for protecting a skilled person . 20
Figure 7 – Flow chart showing the intent of the glass requirements . 22
Figure 8 – Conventional time/current zones of effects of AC currents (15 Hz to 100 Hz)
on persons for a current path corresponding to left hand to feet (see IEC/TS 60479-

1:2005, Figure 20) . 25
Figure 9 – Conventional time/current zones of effects of DC currents on persons for a
longitudinal upward current path (see IEC/TS 60479-1:2005, Figure 22) . 26
Figure 10 – Illustration that limits depend on both voltage and current . 27
Figure 11 – Illustration of working voltage . 41
Figure 12 – Illustration of transient voltages on paired conductor external circuits . 43
Figure 13 – Illustration of transient voltages on coaxial-cable external circuits . 44
Figure 14 – Basic and reinforced insulation in Table 15 14 of IEC 62368-1:20142018;
ratio reinforced to basic . 46
Figure 15 – Reinforced clearances according to Rule 1, Rule 2, and Table 15 14 . 48
Figure 16 – Example illustrating accessible internal wiring . 56
Figure 17 – Waveform on insulation without surge suppressors and no breakdown . 59
Figure 18 – Waveforms on insulation during breakdown without surge suppressors . 59
Figure 19 – Waveforms on insulation with surge suppressors in operation . 60
Figure 20 – Waveform on short-circuited surge suppressor and insulation . 60
Figure 21 – Example for an ES2 source . 62
Figure 22 – Example for an ES3 source . 62
Figure 23 – Overview of protective conductors . 64
Figure 24 – Example of a typical touch current measuring network . 67
Figure 25 – Touch current from a floating circuit . 69
Figure 26 – Touch current from an earthed circuit . 70
Figure 27 – Summation of touch currents in a PABX . 70
Figure 28 – Possible safeguards against electrically-caused fire . 78
Figure 29 – Fire clause flow chart . 81
Figure 30 – Prevent ignition flow chart . 86
Figure 31 – Control fire spread summary . 88
Figure 32 – Control fire spread PS2 . 89
Figure 33 – Control fire spread PS3 . 90
Figure 34 – Fire cone application to a large component . 99
Figure 35 – Flowchart demonstrating the hierarchy of hazard management . 111
Figure 36 – Model for chemical injury . 112
Figure 37 – Direction of forces to be applied . 117
Figure 38 – Model for a burn injury . 120

– 4 – IEC TR 62368-2:2019 RLV © IEC 2019
Figure 39 – Model for safeguards against thermal burn injury . 122
Figure 40 – Model for absence of a thermal hazard . 123
Figure 41 – Model for presence of a thermal hazard with a physical safeguard in place . 123
Figure 42 – Model for presence of a thermal hazard with behavioural safeguard
in place . 123
Figure 43 – Flowchart for evaluation of Image projectors (beamers) . 131
Figure 44 – Graphical representation of L ,T . 133
Aeq
Figure 45 – Overview of operating modes . 139
Figure 46 – Voltage-current characteristics (Typical data) . 143
Figure 47 – Example of IC current limiter circuit . 148
Figure 48 – Current limit curves . 151
Figure 49 – Example of a dummy battery circuit . 161
Figure 50 – Example of a circuit with two power sources.
...

  • Relates Information
  • ISO 8130-9:1992

    ISO 8130-9:1992 - Coating powders
    09-28
  • EN 352-2:2020/FprA1

    EN 352-2:2021/oprA1:2023
    09-28
  • IEC TS 61158-4:1999

    IEC TS 61158-4:1999 - Digital data communications for measurement and control - Fieldbus for use in industrial control systems - Part 4: Data Link protocol specification Released:3/24/1999 Isbn:2831847656
    09-28
  • HD 566 S1:1990

    HD 566 S1:1998
    09-28
  • ISO 5131:1982/Amd 1:1992

    ISO 5131:1982/Amd 1:1992
    09-28
  • EN 60598-2-22:1990

    EN 60598-2-22:1996
    09-27
  • ISO 8504-2:1992

    ISO 8504-2:1992 - Preparation of steel substrates before application of paints and related products -- Surface preparation methods
    09-27
  • EN 12165:2024

    prEN 12165:2022
    09-27
  • IEC TS 61158-6:1999

    IEC TS 61158-6:1999 - Digital data communications for measurement and control - Fieldbus for use in industrial control systems - Part 6: Application Layer protocol specification Released:3/24/1999 Isbn:2831847613
    09-27
  • ISO 4252:1992

    ISO 4252:1992 - Agricultural tractors -- Operator's workplace, access and exit -- Dimensions
    09-27