IEC 61558-2-9:2010

Safety of transformers, reactors, power supply units and combinations thereof - Part 2-9: Particular requirements and tests for transformers and power supply units for class III handlamps for tungsten filament lamps

IEC 61558-2-9:2010 deals with the safety of transformers for class III handlamps for tungsten filament lamps and power supply units incorporating transformers for class III handlamps for tungsten filament lamps. Transformers incorporating electronic circuits are also covered by this standard. This second edition cancels and replaces the first edition published in 2002. It constitutes a technical revision. The main changes consist of updating this part in accordance with IEC 61558-1:2005, and adding power supply units to the scope. This part has the status of a group safety publication in accordance with IEC Guide 104. The attention of National Committees is drawn to the fact that equipment manufacturers and testing organizations may need a transitional period following publication of a new, amended or revised IEC publication in which to make products in accordance with the new requirements and to equip themselves for conducting new or revised tests. It is the recommendation of the committee that the content of this publication be adopted for implementation nationally not earlier than 12 months from the date of publication. In the meantime, the previous edition can still be ordered by contacting your local IEC member National Committee or the IEC Central Office.
This publication is to be read in conjunction with IEC 61558-1:2005.

Sécurité des transformateurs, bobines d'inductance, blocs d'alimentation et des combinaisons de ces éléments - Partie 2-9: Règles particulières et essais pour les transformateurs et blocs d'alimentation pour lampes baladeuses de classe III à filament de tungstène

La CEI 61558-2-9:2010 traite de la sécurité des transformateurs pour lampes baladeuses de classe III pour lampes à filament de tungstène et blocs d'alimentation incorporant des transformateurs pour lampes baladeuses de classe III pour lampes à filament de tungstène. Les transformateurs incorporant des circuits électroniques sont également couverts par la présente norme. Cette deuxième édition annule et remplace la première édition publiée en 2002. Elle constitue une révision technique. Les principales modifications comprennent la mise à jour de la présente partie conformément à la CEI 61558-1:2005, et l'ajout des blocs d'alimentation au domaine d'application. La présente partie a le statut de publication groupée de sécurité conformément au Guide CEI 104. L'attention des Comités Nationaux est attirée sur le fait que les fabricants d'appareils et les organismes d'essai peuvent avoir besoin d'une période transitoire après la publication d'une nouvelle publication CEI, ou d'une publication amendée ou révisée, pour fabriquer des produits conformes aux nouvelles exigences et pour adapter leurs équipements aux nouveaux essais ou aux essais révisés. Le comité recommande que le contenu de cette publication soit entériné au niveau national au plus tôt 12 mois après la date de publication. Pendant ce temps, l'édition précédente peut toujours être commandée auprès du Comité National CEI de votre pays ou auprès du bureau Central de la CEI.
Cette publication doit être lue conjointement avec l'IEC 61558-1:2005.

General Information

• Status: Published
• Publication Date: 28-Jun-2010
• ICS: 29.180 - Transformers. Reactors
• Technical Committee: TC 96 - Transformers and reactors
• Drafting Committee: MT 1 - TC 96/MT 1
• Current Stage: DELPUB - Deleted Publication
• Start Date: 07-Jun-2024
• Completion Date: 17-Oct-2022

Relations

• Revised: IEC 61558-2-9:2024 - Safety of transformers, reactors, power supply units and combinations thereof - Part 2-9: Particular requirements and tests for transformers and power supply units for class III handlamps
• Effective Date: 05-Sep-2023
• Revises: IEC 61558-2-9:2002 - Safety of power transformers, power supply units and similar products - Part 2-9: Particular requirements for transformers for class III handlamps for tungsten filament lamps
• Effective Date: 05-Sep-2023

Overview

IEC 61558-2-9:2010 is an international standard developed by the International Electrotechnical Commission (IEC) that specifies safety requirements and testing procedures for transformers and power supply units designed for class III handlamps using tungsten filament lamps. This standard focuses on ensuring the electrical, thermal, mechanical, and chemical safety of these devices. It replaces the first edition from 2002, updating requirements in line with IEC 61558-1:2005 and expanding the scope to include power supply units incorporating transformers.

The standard applies to stationary or portable, single-phase, air-cooled dry-type transformers, with windings that may be encapsulated or non-encapsulated, operating at frequencies up to 500 Hz. It is relevant to transformers and power supplies with rated output voltages not exceeding 50 V AC or 120 V ripple-free DC and rated power outputs up to 10 kVA.

Key Topics

• Scope and Applicability
  The standard covers transformers and power supply units specifically for class III handlamps with tungsten filament lamps. It addresses devices used in both portable and stationary applications, focusing on air-cooled, dry-type transformers with linear power supplies.

• Safety Requirements
  IEC 61558-2-9:2010 mandates protection against electric shock, thermal hazards, mechanical risks, and chemical safety. It lays down test procedures for insulation resistance, dielectric strength, mechanical strength, temperature rise, and resistance to dust and moisture ingress.

• Electrical Characteristics
  This includes limits on no-load and rated output voltages, short circuit conditions, output current under load, and voltage regulation. The standard emphasizes the importance of minimizing the difference between no-load voltage and rated output voltage for safety and performance.

• Construction and Components
  Requirements for the construction of transformers and power supplies cover internal wiring, terminal design, creepage distances, clearances, and component selection to ensure reliability and compliance with safety regulations.

• Testing Procedures
  The standard specifies a comprehensive suite of tests, including temperature rise tests, short-circuit and overload protection tests, insulation resistance tests, and mechanical strength assessments to verify compliance with the specified safety criteria.

• Marking and Documentation
  Clear marking for electrical ratings, voltage settings, and safety instructions are required to inform manufacturers, testers, and end-users, ensuring proper installation and operation.

• Compatibility with IEC 61558-1
  IEC 61558-2-9 is intended to be used in conjunction with IEC 61558-1:2005, which contains the general safety requirements for transformers and power supply units. Where conflicts arise between the two standards, the more stringent requirement applies.

Applications

IEC 61558-2-9:2010 is critical for manufacturers, testing laboratories, and certification bodies involved with:

• Producing transformers and power supply units for class III handlamps featuring tungsten filament lamps.
• Designing portable or stationary lighting equipment requiring low-voltage safety measures.
• Ensuring compliance with international safety standards to access global markets.
• Implementing robust safety protocols in handlamp power supplies used in industrial, commercial, or residential settings.
• Testing and certifying electrical devices with transformers operating up to 500 Hz and rated for output voltages under 50 V AC.

The standard also benefits end-product manufacturers who integrate such transformers and power supplies into their handlamps by facilitating the adherence to recognized safety protocols.

Related Standards

• IEC 61558-1:2005 – General requirements and tests for transformers, reactors, power supply units, and their combinations. This is the foundational standard used alongside IEC 61558-2-9.

• IEC 61558-2-16 – Specific requirements for switch mode power supply (SMPS) units. IEC 61558-2-9 references this standard when addressing power supplies with operational frequencies higher than 500 Hz.

• IEC Guide 104:1997 – Guidelines for the preparation of safety publications, including basic and group safety publications, providing procedural context for this standard.

• Additional IEC standards related to insulation, mechanical durability, and testing procedures that support the comprehensive safety framework for electrical transformers and power supplies.

---

By adhering to IEC 61558-2-9:2010, manufacturers and stakeholders ensure the safe design, construction, and testing of transformers and power supplies for class III handlamps with tungsten filament lamps, facilitating international compliance, enhancing user safety, and promoting product reliability.

Standards Content (Sample)

IEC 61558-2-9 ®
Edition 2.0 2010-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
GROUP SAFETY PUBLICATION
PUBLICATION GROUPÉE DE SÉCURITÉ

Safety of transformers, reactors, power supply units and combinations thereof –
Part 2-9: Particular requirements and tests for transformers and power supply
units for class III handlamps for tungsten filament lamps

Sécurité des transformateurs, bobines d’inductance, blocs d’alimentation et des
combinaisons de ces éléments –
Partie 2-9: Règles particulières et essais pour les transformateurs et blocs
d’alimentation pour lampes baladeuses de classe III à filament de tungstène

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IEC 61558-2-9 ®
Edition 2.0 2010-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
GROUP SAFETY PUBLICATION
PUBLICATION GROUPÉE DE SÉCURITÉ

Safety of transformers, reactors, power supply units and combinations thereof –
Part 2-9: Particular requirements and tests for transformers and power supply
units for class III handlamps for tungsten filament lamps

Sécurité des transformateurs, bobines d’inductance, blocs d’alimentation et des
combinaisons de ces éléments –
Partie 2-9: Règles particulières et essais pour les transformateurs et blocs
d’alimentation pour lampes baladeuses de classe III à filament de tungstène

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
M
CODE PRIX
ICS 29.180 ISBN 978-2-88912-037-6
– 2 – 61558-2-9 © IEC:2010
CONTENTS
FOREWORD.3
1 Scope.5
2 Normative references .6
3 Terms and definitions .6
4 General requirements .6
5 General notes on tests .6
6 Ratings.6
7 Classification.7
8 Marking and other information .7
9 Protection against electric shock .7
10 Change of input voltage setting .8
11 Output voltage and output current under load .8
12 No-load output voltage .8
13 Short-circuit voltage .9
14 Heating .9
15 Short-circuit and overload protection .9
16 Mechanical strength .9
17 Protection against harmful ingress of dust, solid objects and moisture.9
18 Insulation resistance, dielectric strength and leakage current .9
19 Construction .9
20 Components .11
21 Internal wiring.11
22 Supply connection and other external flexible cable or cords .11
23 Terminals for external conductors.11
24 Provisions for protective earthing .12
25 Screws and connections .12
26 Creepage distances, clearances and distances through insulation.12
27 Resistance to heat, fire and tracking.12
28 Resistance to rusting.12
Annexes .13
Bibliography.13

Table 101 – Ratio of output voltages for transformers for class III tungsten filament
handlamps .8

61558-2-9 © IEC:2010 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SAFETY OF TRANSFORMERS, REACTORS,
POWER SUPPLY UNITS AND COMBINATIONS THEREOF –

Part 2-9: Particular requirements and tests for transformers and
power supply units for class III handlamps for tungsten filament lamps

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,
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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
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
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6) All users should ensure that they have the latest edition of this publication.
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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 61558-2-9 has been prepared by IEC technical committee 96:
Transformers, reactors, power supply units and combinations thereof.
This second edition cancels and replaces the first edition published in 2002. It constitutes a
technical revision. The main changes consist of updating this part in accordance with
IEC 61558-1:2005, and adding power supply units to the scope.
This part has the status of a group safety publication in accordance with IEC Guide 104:
1997, The preparation of safety publications and the use of basic safety publications and
group safety publications.
– 4 – 61558-2-9 © IEC:2010
The text of this standard is based on the following documents:
FDIS Report on voting
96/355/FDIS 96/362/RVD
Full information on the voting for the approval of this standard 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.
This part is intended to be used in conjunction with the latest edition of IEC 61558-1 and its
amendments. It is based on the second edition (2005) of that standard.
This part supplements or modifies the corresponding clauses in IEC 61558-1, so as to convert
that publication into the IEC standard: Particular requirements and tests for transformers and
power supply units for class III handlamps for tungsten filament lamps.
A list of all parts of the IEC 61558 series, under the general title: Safety of transformers,
reactors, power supply units and combinations thereof, can be found on the IEC website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
Where a particular subclause of Part 1 is not mentioned in this part, that subclause applies as
far as is reasonable. Where this part states "addition", "modification" or "replacement", the
relevant text of Part 1 is to be adopted accordingly.
In this part, the following print types are used:
– requirements proper: in roman type;
– test specifications: in italic type;
– explanatory matters: in smaller roman type.
In the text of this part, the words in bold are defined in Clause 3.
Subclauses additional to those in Part 1 are numbered starting from 101; supplementary
annexes are entitled AA, BB, etc.
The committee has decided that the contents of this publication 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.
NOTE The attention of National Committees is drawn to the fact that equipment manufacturers and testing
organizations may need a transitional period following publication of a new, amended or revised IEC publication in
which to make products in accordance with the new requirements and to equip themselves for conducting new or
revised tests.
It is the recommendation of the committee that the content of this publication be adopted for implementation
nationally not earlier than 12 months from the date of publication.

61558-2-9 © IEC:2010 – 5 –
SAFETY OF TRANSFORMERS, REACTORS,
POWER SUPPLY UNITS AND COMBINATIONS THEREOF –

Part 2-9: Particular requirements and tests for transformers and
power supply units for class III handlamps for tungsten filament lamps

1 Scope
Replacement:
This part of IEC 61558 deals with the safety of transformers for class III handlamps for
tungsten filament lamps and power supply units incorporating transformers for class III
handlamps for tungsten filament lamps. Transformers incorporating electronic circuits
are also covered by this standard.
NOTE 1 Safety includes electrical, thermal, mechanical and chemical aspects.
Unless otherwise specified, from here onward, the term transformer covers transformers for
class III handlamps for tungsten filament lamps and power supply units incorporating
transformers for class III handlamps for tungsten filament lamps.
This part is applicable to stationary or portable single-phase air-cooled (natural or forced)
independent or associated dry-type transformers. The windings may be encapsulated or
non-encapsulated.
This standard is applicable to transformers and power supply (linear) with internal
operational frequencies not exceeding 500 Hz.
This standard used in combination with Part 2-16 for switch mode power supply (SMPS)
units is also applicable to power supplies with internal operational frequencies higher than
500 Hz. Where the two requirements are in conflict, the most severe take precedence.
The rated supply voltage does not exceed 1 000 V a.c., and the rated supply frequency
and the internal operational frequencies do not exceed 500 Hz.
Transformers for class III handlamps for tungsten filament lamps have the following
additional characteristics:
– the no-load output voltage and the rated output voltage do not exceed 50 V a.c. or
120 V ripple-free d.c.;
– there is only a small difference between the no-load voltage and the rated output
voltage.
The rated output does not exceed:
– 10 kVA.
This part is not applicable to external circuits and their components intended to be connected
to the input terminals and output terminals of the transformers.
Transformers covered by this part are used in applications where double or reinforced
insulation between circuits is required by the installation rules or by the end product
standard.
NOTE 2 Attention is drawn to the following:

– 6 – 61558-2-9 © IEC:2010
- for transformers intended to be used in vehicles, on board ships, and aircraft, additional requirements (from
other applicable standards, national rules, etc.) may be necessary;
- measures to protect the enclosure and the components inside the enclosure against external influences such
as fungus, vermin, termites, solar-radiation, and icing should also be considered;
- the different conditions for transportation, storage, and operation of the transformers should also be
considered;
- additional requirements in accordance with other appropriate standards and national rules may be applicable to
transformers intended for use in special environments.
NOTE 3 Future technological development of transformers may necessitate a need to increase the upper limit of
the frequencies, until then this part may be used as a guidance document.
2 Normative references
This clause of Part 1 is applicable except as follows:
Addition:
IEC 61558-1:2005, Safety of power transformers, power supplies, reactors and similar
products – Part 1: General requirements and tests
3 Terms and definitions
This clause of Part 1 is applicable, except as follows:
Addition:
3.1.101
transformer for class III handlamps for tungsten filament lamps
associated safety isolating transformer intended to supply one or more class III handlamps
for tungsten filament lamps
3.1.102
power supply unit incorporating transformer for class III handlamps for tungsten
filament lamps
power supply unit where an associated safety isolating transformer is used intended to
supply one or more class III handlamps for tungsten filament lamps
4 General requirements
This clause of Part 1 is applicable.
5 General notes on tests
This clause of Part 1 is applicable.
6 Ratings
This clause of Part 1 is applicable, except as follows:
Addition:
6.101 The rated output voltage shall not exceed 50 V a.c. or 120 V ripple-free d.c.

61558-2-9 © IEC:2010 – 7 –
6.102 The rated output shall not exceed 10 kVA.
6.103 The rated supply frequency and internal operational frequencies shall not exceed
500 Hz.
6.104 The rated supply voltage shall not exceed 1 000 V a. c.
Compliance with 6.101 to 6.104 is checked by inspection of the marking.
7 Classification
This clause of Part 1 is applicable, except as follows:
7.2 Replacement:
According to short-circuit protection or protection against abnormal conditions:
– inherently short-circuit proof transformers;
– non-inherently short-circuit proof transformers.
7.3 Replacement:
Degree of protection provided by the enclosure for portable transformers shall be code
IP24 or higher.
7.5 Replacement:
According to their duty-time:
– continuous operation.
8 Marking and other information
This clause of Part 1 is applicable, except as follows:
8.11 Addition:
Symbol or graphical Explanation or title Identification
symbol
Short-circuit proof transformer for class III tungsten IEC 60417-5953 (2002-10)
filament handlamps (inherently or non-inherently)

Addition:
8.101 For transformers intended for connection to the supply by means of a cable or cord
and a plug, an instruction sheet or the equivalent shall be delivered with the transformer,
drawing the attention of the user to the fact that the output circuit(s) shall be protected in
accordance with national wiring rules.
9 Protection against electric shock
This clause of Part 1 is applicable.

– 8 – 61558-2-9 © IEC:2010
10 Change of input voltage setting
This clause of Part 1 is applicable.
11 Output voltage and output current under load
This clause of Part 1 is applicable, except as follows:
11.1 Replace the first paragraph by the following:
When the transformer is connected to the rated supply voltage at the rated supply
frequency, and loaded with an impedance resulting in the rated output at the rated output
voltage, and for a.c. current, at the rated power factor, the output voltage under load shall
not differ from the rated output voltage by more than 5 %. For transformers with rectifiers,
the output voltage under load shall not differ from the rated output voltage by more than
10 %.
12 No-load output voltage
This clause of Part 1 is applicable except as follows:
Addition:
The no-load output voltage is measured when the transformer is connected to the rated
supply voltage at the rated supply frequency at ambient temperature.
12.101 The no-load output voltage shall not exceed 50 V a.c. or 120 V ripple-free d.c.
For independent transformers, this output voltage limitation applies even when output
windings, not intended for interconnection, are connected in series.
12.102 The difference between the no-load output voltage and the output voltage under
load (as measured in 11.1) shall not be excessive The difference is expressed as a
percentage of the latter voltage calculated according to the following formula:
UU−
no-load load
× 100 (%)
U
load
where U is the no-load output voltage and U is the output voltage under load.
no-load load
Table 101 – Ratio of output voltages for transformers for
class III tungsten filament handlamps
Rated output of transformer Ratio between no-load output voltage and
output voltage under load
VA %
− up to and including 63 7,5
− over 63 up to and including 630 5,0
2,5
− over 630
Compliance with the requirements of 12.101 and 12.102 is checked by measuring the no-load
output voltage at the ambient temperature when the transformer is connected to the rated
supply voltage at the rated supply frequency.

61558-2-9 © IEC:2010 – 9 –
The difference shall not exceed the values shown in Table 101.
13 Short-circuit voltage
This clause of Part 1 is applicable.
14 Heating
This clause of Part 1 is applicable.
15 Short-circuit and overload protection
This clause of Part 1 is applicable.
16 Mechanical strength
This clause of Part 1 is applicable.
17 Protection against harmful ingress of dust, solid objects and moisture
This clause of Part 1 is applicable.
18 Insulation resistance, dielectric strength and leakage current
This clause of Part 1 is applicable.
19 Construction
This clause of Part 1 is applicable except as follows:
Replacement of 19.1:
19.1 The input and output circuits shall be electrically separated from each other, and the
construction shall be such that there is no possibility of any connection between these circuits
directly or indirectly via other metal parts, except by deliberate action.
Compliance is checked by inspection and measurements, taking Clauses 18 and 26 into
consideration.
19.1.1 The insulation between input and output winding(s) shall consist of double or
reinforced insulation (rated for the working voltage).
In addition, the following applies:
– for class I transformers not intended for connection to the mains supply by means of a
plug, the insulation between the input windings and the body connected to earth shall
consist of at least basic insulation rated for the input voltage. The insulation between the
output windings and the body connected to earth, shall consist of at least basic
insulation (rated for the output voltage);
– for class I transformers intended for connection to the mains supply by means of a plug,
the insulation between the input windings and the body shall consist of at least basic
insulation, and the insulation between the output windings and the body shall consist of

– 10 – 61558-2-9 © IEC:2010
at least supplementary insulation (both basic and supplementary insulations rated for
the working voltage);
– for class II transformers, the insulation between the input windings and the body shall
consist of double or reinforced insulation (rated for the input voltage). The insulation
between the output windings and the body, shall consist of double or reinforced
insulation (rated for the output voltage).
19.1.2 For transformers with intermediate conductive parts (e.g. the iron core) not
connected to the body and located between the input and output windings, the following
requirements are applicable:
– for class I and class II transformers, the insulation between the input and output
windings via the intermediate conductive parts shall consist of double or reinforced
insulation (rated for the working voltage);
– for class II transformers, the insulation between the input windings and the body, and
between the output windings and the body via the intermediate conductive parts shall
consist of double or reinforced insulation (rated for the input and output voltage);
– for transformer different from independent (IP00), the insulation between the input and
output windings via the intermediate conductive parts shall consist of double or
reinforced insulation (rated for the working voltage);
– as alternative to the above mentioned requirements for class I transformer not intended
to be connected by means of a plug and for transformer different from independent
(IP00), if the construction assure that all laminated plates of the iron core are connected
to earth (e.g by soldering / welding) and if the in data sheet or instruction sheet clearly
state that the safety of the transformer depends on the earth connection and that is not
possible to use in class II equipment, than the following apply: the insulation between the
input windings and the intermediate conductive part connected to earth, and between
the output windings and the intermediate conductive part connected to earth, shall
consist of at least basic insulation (rated for the input and output voltage);
– in addition to the above requirements the insulation between the intermediate conductive
parts and the input windings, and between the intermediate conductive parts and the
output windings shall consist of at least basic insulation (rated for the input and output
voltage). An intermediate conductive part not separated from the input or output
windings or the body by at least basic insulation is considered to be connected to the
relevant part(s).
19.1.3 For class I transformers not intended for connection to the mains supply by means
of a plug, the insulation between the input and output windings may consist of basic
insulation plus protective screening instead of double or reinforced insulation, provided
the following conditions are complied with:
– the insulation between the input winding and the protective screen shall comply with the
requirements for basic insulation (rated for the input voltage);
– the insulation between the protective screen and the output winding shall comply with
the requirements for basic insulation (rated for the output voltage);
– the protective screen shall, unless otherwise specified, consist of a metal foil or of a
wire- wound screen extending at least the full width of the input winding and shall have
no gaps or holes;
– where the protective screen does not cover the entire width of the input winding,
additional adhesive tapes or equivalent insulation shall be used to ensure double
insulation in that area;
– if the protective screen is made of a foil, the turns shall be insulated from each other.
In case of only one turn, it shall have an isolated overlap of at least 3 mm;
– the wire of a wire-wound screen and the lead-out wire of the protective screen shall have
a cross-sectional area at least corresponding to the rated current of the overload
protective device to ensure that if a breakdown of insulation should occur, the overload
protective device will open the circuit before the lead-out wire is destroyed;

61558-2-9 © IEC:2010 – 11 –
– the lead-out wire shall be soldered to the protective screen or secured in an equally
reliable manner.
NOTE For the purpose of this subclause, the term “windings” does not include internal circuits
Examples of construction of windings are given in Annex M of Part 1.
19.16 Replacement:
Portable transformers shall have a protection code of at least IP24.
Addition:
19.101 There shall be no connection between output circuits and the protective earth,
associated transformers by the relevant equipment standard.
unless this is allowed for
19.102 There shall be no connection between output circuits and the body, unless this is
allowed for associated transformers by the relevant equipment standard.
Compliance is checked by inspection.
19.103 The input and output terminals for the connection of external wiring shall be so
located that the distance measured between the points of introduction of the conductors into
these terminals is not less than 25 mm. If a barrier is used to obtain this distance, the
measurement shall be made over and around the barrier which shall be of insulating material
and permanently fixed to the transformer.
Compliance is checked by inspection and by measurement disregarding intermediate
conductive parts.
19.104 Portable transformers having a rated output not exceeding 630 VA shall be
class II.
20 Components
This clause of Part 1 is applicable.
21 Internal wiring
This clause of Part 1 is applicable.
22 Supply connection and other external flexible cable or cords
This clause of Part 1 is applicable, except as follows:
22.5 Addition:
Power supply cords of transformers with a protection code of other than IPX0 shall not be
lighter than ordinary polychloroprene sheathed cords (code designation 60245 IEC 57).
23 Terminals for external conductors
This clause of Part 1 is applicable.

– 12 – 61558-2-9 © IEC:2010
24 Provisions for protective earthing
This clause of Part 1 is applicable.
25 Screws and connections
This clause of Part 1 is applicable.
26 Creepage distances, clearances and distances through insulation
This clause of Part 1 is applicable except as follows:
Addition:
26.101 The values for creepage distances, clearances and distances through insulation for
working voltages above 1 000 V may be found by extrapolation.
27 Resistance to heat, fire and tracking
This clause of Part 1 is applicable.
28 Resistance to rusting
This clause of Part 1 is applicable.

61558-2-9 © IEC:2010 – 13 –
Annexes
The annexes of Part 1 are applicable.

Bibliography
The Bibliography of Part 1 is applicable except as follows:
Addition:
IEC 61558-2-16:2009, Safety of transformers, reactors, power supply units and similar
products for supply voltages up to 1 100 V – Part 2-16: Particular requirements and tests for
switch mode power supply units and transformers for switch mode power supply units

___________
– 14 – 61558-2-9 © CEI:2010
SOMMAIRE
AVANT-PROPOS.15
1 Domaine d’application .17
2 Références normatives.18
3 Termes et définitions .18
4 Exigences générales .18
5 Généralités sur les essais .18
6 Caractéristiques assignées.19
7 Classification.19
8 Marquage et autres indications.19
9 Protection contre les chocs électriques.20
10 Changement de la tension primaire d’alimentation.20
11 Tension secondaire et courant secondaire en charge .20
12 Tension secondaire à vide.20
13 Tension de court-circuit .21
14 Echauffements .21
15 Protection contre les courts-circuits et les surcharges .21
16 Résistance mécanique .21
17 Protection contre les effets nuisibles dus à la pénétration de poussière, d’objets
solides et de l’humidité .21
18 Résistance d'isolement, rigidité diélectrique et courant de fuite .21
19 Construction .21
20 Composants .24
21 Conducteurs internes .24
22 Raccordement à l’alimentation et câbles souples externes .24
23 Bornes pour conducteurs externes .24
24 Dispositions en vue de la mise à la terre .24
25 Vis et connexions .24
26 Lignes de fuite, distances d’isolement et distances à travers l’isolation .24
27 Résistance à la chaleur, au feu et aux courants de cheminement .24
28 Protection contre la rouille.25
Annexes .26
Bibliographie.26

Tableau 101 – Rapport des tensions secondaires pour les transformateurs pour
lampes baladeuses de classe III à filament de tungstène .21

61558-2-9 © CEI:2010 – 15 –
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
SÉCURITÉ DES TRANSFORMATEURS, BOBINES D’INDUCTANCE,
BLOCS D’ALIMENTATION ET DES COMBINAISONS DE CES ÉLEMENTS –

Partie 2-9: Règles particulières et essais pour les transformateurs
et blocs d’alimentation pour lampes baladeuses
de classe III à filament de tungstène

AVANT-PROPOS
1) La Commission Electrotechnique Internationale (CEI) est une organisation mondiale de normalisation
composée de l'ensemble des comités électrotechniques nationaux (Comités nationaux de la CEI). La CEI a
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internationales, des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au
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également aux travaux. La CEI collabore étroitement avec l'Organisation Internationale de Normalisation (ISO),
selon des conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de la CEI concernant les questions techniques représentent, dans la mesure
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3) Les Publications de la CEI se présentent sous la forme de recommandations internationales et sont agréées
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7) Aucune responsabilité ne doit être imputée à la CEI, à ses administrateurs, employés, auxiliaires ou
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8) L'attention est attirée sur les références normatives citées dans cette publication. L'utilisation de publications
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9) L’attention est attirée sur le fait que certains des éléments de la présente Publication de la CEI peuvent faire
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responsable de ne pas avoir identifié de tels droits de propriété et de ne pas avoir signalé leur existence.
La Norme internationale CEI 61558-2-9 a été établie par le comité d'études 96 de la CEI:
Transformateurs, bobines d’inductance, blocs d'alimentation et combinaisons de ces
éléments.
Cette deuxième édition annule et remplace la première édition publiée en 2002. Elle constitue
une révision technique. Les principales modifications comprennent la mise à jour de la
présente partie conformément à la CEI 61558-1:2005, et l’ajout des blocs d’alimentation au
domaine d’application.
La présente partie a le statut de publication groupée de sécurité conformément au Guide CEI
104:1997, Elaboration des publications de sécurité et utilisation des publications
fondamentales de sécurité et publications groupées de sécurité.

– 16 – 61558-2-9 © CEI:2010
Le texte de cette norme est issu des documents suivants:
FDIS Rapport de vote
96/355/FDIS 96/362/RVD
Le rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant
abouti à l'approbation de cette norme.
Cette publication a été rédigée conformément aux Directives ISO/CEI, Partie 2.
La présente partie est destinée à être utilisée avec la dernière édition de la CEI 61558-1 et
ses amendements. Elle est issue de la seconde édition (2005) de cette norme
La présente partie complète ou modifie les articles correspondants de la CEI 61558-1, de façon à
transformer cette publication en norme CEI: Règles particulières et essais pour les trans-
formateurs et blocs d’alimentation pour lampes baladeuses de classe III à filament de tungstène.
Une liste de toutes les parties de la série CEI 61558, sous le titre général: Sécurité des
transformateurs, bobine
...