IEC 61558-2-12:2011

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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