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.

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Status
Published
Publication Date
28-Jun-2010
Current Stage
PPUB - Publication issued
Start Date
29-Jun-2010
Completion Date
29-Jun-2010
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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
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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
IEC 61558-2-9:2010
---------------------- Page: 1 ----------------------
THIS PUBLICATION IS COPYRIGHT PROTECTED
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---------------------- Page: 2 ----------------------
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
CODE PRIX
ICS 29.180 ISBN 978-2-88912-037-6
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 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

---------------------- Page: 4 ----------------------
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,

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

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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.

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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 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.
---------------------- Page: 5 ----------------------
– 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.
---------------------- Page: 6 ----------------------
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:
---------------------- Page: 7 ----------------------
– 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.

---------------------- Page: 8 ----------------------
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.
---------------------- Page: 9 ----------------------
– 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 (%)
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.
---------------------- Page: 10 ----------------------
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

---------------------- Page: 11 ----------------------
– 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
...

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