IEC 61558-2-26:2013

IEC 61558-2-26 ®
Edition 1.0 2013-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Safety of transformers, reactors, power supply units and combinations thereof –
Part 2-26: Particular requirements and tests for transformers and power supply
units all for saving energy and other purposes

Sécurité des transformateurs, bobines d’inductance, blocs d’alimentation et des
combinaisons de ces éléments –
Partie 2-26: Règles particulières et essais pour les transformateurs et les blocs
d’alimentation entièrement destinés à l’économie d’énergie et à d’autres fins

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IEC 61558-2-26 ®
Edition 1.0 2013-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Safety of transformers, reactors, power supply units and combinations thereof –

Part 2-26: Particular requirements and tests for transformers and power supply

units all for saving energy and other purposes

Sécurité des transformateurs, bobines d’inductance, blocs d’alimentation et des

combinaisons de ces éléments –

Partie 2-26: Règles particulières et essais pour les transformateurs et les blocs

d’alimentation entièrement destinés à l’économie d’énergie et à d’autres fins

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX R
ICS 29.180 ISBN 978-2-8322-0913-4

– 2 – 61558-2-26 © IEC:2013
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 6
3 Terms and definitions . 7
4 General requirements . 8
5 General notes on test . 8
6 Ratings . 9
7 Classification . 9
8 Marking and other information . 9
9 Protection against electric shock . 10
10 Change of input voltage setting . 11
11 Output voltage and output current under load . 11
12 No-load output voltage . 12
13 Short-circuit voltage . 12
14 Heating. 12
15 Short circuit and overload protection . 13
16 Mechanical strength . 13
17 Protection against harmful ingress of dust, solid objects and moisture . 13
18 Insulation resistance, dielectric strength and leakage current . 13
19 Construction . 13
20 Components . 15
21 Internal wiring . 15
22 Supply connection and other external flexible cables or cords . 15
23 Terminals for external conductors . 15
24 Provisions for protective earthing . 15
25 Screws and connections . 15
26 Creepage distances, clearances and distances through insulation . 15
27 Resistance to heat, fire and tracking . 15
28 Resistance to rusting . 15
Annexes . 16
Annex B (normative) Testing a series of transformers . 16
Annex L (normative) Routine tests (production test) . 16
Annex AA (informative) Saving energy . 17
Annex BB (informative) Incorporated transformers . 18
Bibliography . 19

Table 101 – Output voltage difference . 12

61558-2-26 © IEC:2013 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SAFETY OF TRANSFORMERS, REACTORS,
POWER SUPPLY UNITS AND COMBINATIONS THEREOF –

Part 2-26: Particular requirements and tests for transformers and
power supply units all for saving energy and other purposes

FOREWORD
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International standard IEC 61558-2-26 has been prepared by IEC technical committee 96:
Transformers, reactors, power supply units and combinations thereof.
The text of this standard is based on the following documents:
FDIS Report on voting
96/400/FDIS 96/404/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.
...