IEC 61558-2-12:2011

Safety of transformers, reactors, power supply units and combination thereof - Part 2-12: Particular requirements and tests for constant voltage transformers and power supply units for constant voltage

IEC 61558-2-12:2011 deals with the safety of constant voltage transformers for general applications and power supply units for constant voltage for general applications. Constant voltage transformers incorporating electronic circuits are also covered by this standard. This second edition cancels and replaces the first edition published in 2001. It constitutes a technical revision. The main changes consist of updating this part in accordance with IEC 61558-1:2009. This part has the status of a group safety publication in accordance with IEC Guide 104: The preparation of safety publications and the use of basic safety publications and group safety publications. 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 2-12: Exigences particulières et essais pour les transformateurs à tension constante et les blocs d'alimentation pour tension constante

La CEI 61558-2-12:2011 traite de la sécurité des transformateurs à tension constante pour applications d'ordre général et des blocs d'alimentation pour tension constante pour applications d'ordre général. Les transformateurs à tension constante incorporant des circuits électroniques sont également couverts par la présente norme. Cette deuxième édition annule et remplace la première édition parue en 2001, dont elle constitue une révision technique. Les principales modifications consistent en la mise à jour de la présente partie, conformément à la CEI 61558-1:2009. La présente partie a le statut de publication groupée de sécurité, conformément au Guide CEI 104: Élaboration des publications de sécurité et utilisation des publications fondamentales de sécurité et publications groupées de sécurité. L'attention des Comités nationaux est attirée sur le fait que les constructeurs des appareils et les organismes d'essai peuvent avoir besoin d'une période transitoire, à la parution d'une publication CEI qu'elle soit nouvelle, modifiée ou révisée, pour mettre les produits en conformité avec les nouvelles exigences et pour s'équiper eux-mêmes afin de réaliser de nouveaux essais ou des essais révisés. Le comité recommande que le contenu de la présente publication soit adopté pour mise en uvre 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 la CEI 61558-1:2005.

General Information

• Status: Published
• Publication Date: 26-Jan-2011
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.180 - Transformers. Reactors
• ICS: 31.080.01 - Semiconductor devices in general
• Technical Committee: TC 96 - Transformers, reactors, power supply units, and combinations thereof
• Drafting Committee: MT 1 - TC 96/MT 1

Relations

• Revised: IEC 61558-2-12:2024 - Safety of transformers, reactors, power supply units and combinations thereof - Part 2-12: Particular requirements and tests for constant voltage transformers and power supply units for constant voltage
• Effective Date: 05-Sep-2023
• Revises: IEC 61558-2-12:2001 - Safety of power transformers, power supply units and similar devices - Part 2-12: Particular requirements for constant voltage transformers
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61558-2-12 ®
Edition 2.0 2011-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
GROUP SAFETY PUBLICATION
PUBLICATION GROUPÉE DE SÉCURITÉ

Safety of transformers, reactors, power supply units and combination thereof –
Part 2-12: Particular requirements and tests for constant voltage transformers
and power supply units for constant voltage

Sécurité des transformateurs, bobines d’inductance, blocs d’alimentation et des
combinaisons de ces éléments –
Partie 2-12: Exigences particulières et essais pour les transformateurs à tension
constante et les blocs d'alimentation pour tension constante

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IEC 61558-2-12 ®
Edition 2.0 2011-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
GROUP SAFETY PUBLICATION
PUBLICATION GROUPÉE DE SÉCURITÉ

Safety of transformers, reactors, power supply units and combination thereof –
Part 2-12: Particular requirements and tests for constant voltage transformers
and power supply units for constant voltage

Sécurité des transformateurs, bobines d’inductance, blocs d’alimentation et des
combinaisons de ces éléments –
Partie 2-12: Exigences particulières et essais pour les transformateurs à tension
constante et les blocs d'alimentation pour tension constante
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX S
ICS 29.180 ISBN 978-2-88912-341-4

– 2 – 61558-2-12  IEC:2011
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 7
3 Terms and definitions . 7
4 General requirements . 7
5 General notes on tests . 7
6 Ratings . 7
7 Classification . 8
8 Marking and other information . 8
9 Protection against electric shock . 9
10 Change of input voltage setting . 9
11 Output voltage and output current under load . 9
12 No-load output voltage . 10
13 Short-circuit voltage . 11
14 Heating . 11
15 Short-circuit and overload protection . 11
16 Mechanical strength . 12
17 Protection against harmful ingress of dust, solid objects and moisture . 12
18 Insulation resistance, dielectric strength and leakage current . 12
19 Construction . 13
20 Components . 17
21 Internal wiring . 17
22 Supply connection and other external flexible cables or cords . 17
23 Terminals for external conductors . 17
24 Provision for protective earthing . 17
25 Screws and connections . 17
26 Creepage distances, clearances and distances through insulation . 17
27 Resistance to heat, fire and tracking . 18
28 Resistance to rusting . 18
Annexes . 19
Annex C (normative) . 19
Annex D (normative) . 19
Annex L (normative) . 19
Annex R (normative) . 19
Bibliography . 20

61558-2-12  IEC:2011 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SAFETY OF TRANSFORMERS, REACTORS,
POWER SUPPLY UNITS AND COMBINATION THEREOF –

Part 2-12: Particular requirements and tests
for constant voltage transformers
and power supply units for constant voltage

FOREWORD
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International Standard IEC 61558-2-12 has been prepared by IEC technical committee 96:
Transformers, reactors, power supply units, and combination thereof.
This second edition cancels and replaces the first edition published in 2001. It constitutes a
technical revision. The main changes consist of updating this part in accordance with
IEC 61558-1:2009.
This part has the status of a group safety publication in accordance with IEC Guide 104: The
preparation of safety publications and the use of basic safety publications and group safety
publications.
– 4 – 61558-2-12  IEC:2011
The text of this standard is based u
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