IEC 60076-21:2011

Power transformers - Part 21: Standard requirements, terminology, and test code for step-voltage regulators

IEC 60076-21:2011/IEEE Std C57.15:2009 - Description of design types, tables of 50 Hz and 60 Hz ratings, supplementary ratings, construction, and available accessories are provided. Methods for performing routine and design tests applicable to liquid-immersed single and three-phase step-voltage regulators are described. Winding resistance measurements, polarity tests, insulation power factor and resistance tests, ratio tests, no load loss and excitation current measurements, impedance and load loss measurements, dielectric tests, temperature tests, routine and design impulse tests, short-circuit tests, control tests, calculated data, and certified test data are covered.

General Information

• Status: Published
• Publication Date: 14-Dec-2011
• ICS: 29.180 - Transformers. Reactors
• Technical Committee: TC 14 - Power transformers
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 07-Dec-2018

Relations

• Revised: IEC 60076-21:2018 - Power transformers - Part 21: Standard requirements, terminology, and test code for step-voltage regulators
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60076-21
Edition 1.0 2011-12
™
IEEE Std C57.15
INTERNATIONAL
STANDARD
Power transformers –
Part 21: Standard requirements, terminology, and test code for step-voltage
regulators
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IEC 60076-21
Edition 1.0 2011-12
™
IEEE Std C57.15
INTERNATIONAL
STANDARD
Power transformers –
Part 21: Standard requirements, terminology, and test code for step-voltage
regulators
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XD
ICS 29.180 ISBN 978-2-88912-848-8

– i – IEC 60076-21:2011(E)
IEEE Std C57.15-2009
Contents
1. Overview . 1

1.1 Scope . 1

1.2 Purpose . 1

1.3 Word usage . 1

2. Normative references . 2

3. Definitions . 3

4. Service conditions . 9
4.1 Usual service conditions . 9
4.2 Loading at other than rated conditions .10
4.3 Unusual service conditions .10
4.4 Frequency .12
5. Rating data .12
5.1 Cooling classes of voltage regulators .12
5.2 Ratings .13
5.3 Supplementary continuous-current ratings .17
5.4 Taps .18
5.5 Operating voltage limits .18
5.6 Voltage supply ratios .20
5.7 Insulation levels .20
5.8 Losses .21
5.9 Short-circuit requirements .22
5.10 Tests .23
6. Construction .24
6.1 Bushings .24
6.2 Terminal markings .25
6.3 Diagram of connections .26
6.4 Nameplates .26
6.5 Tank construction .27
6.6 Components and accessories .31
7. Other requirements .32
7.1 Other supplementary continuous-current ratings .32
7.2 Other components and accessories .32
8. Test code.33

8.1 Resistance measurements .34
8.2 Polarity test .36
8.3 Ratio tests .37
8.4 No-load losses and excitation current .40
8.5 Load losses and impedance voltage .45
8.6 Dielectric tests .51
8.7 Temperature-rise tests .64
8.8 Short-circuit tests .73
8.9 Calculated data .77
9. Control systems .81
Published by the IEC under licence from IEEE. © 2009 IEEE. All rights reserved.

IEEE Std C57.15-2009
9.1 General .81

9.2 Control device construction .81

9.3 Control system requirements .82

9.4 Tests .83

Annex A (informative) Unusual temperature and altitude conditions .87

Annex B (informative) Field dielectric tests.89

Annex C (informative) Bibliography.90

Annex D (informative) IEEE List of Participants .92

Published by the IEC under licence from IEEE. © 2009 IEEE. All rights reserved.

– iii – IEC 60076-21:2011(E)
IEEE Std C57.15-2009
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
POWER TRANSFORMERS –
Part 21: Standard requirements, terminology,

and test code for step-voltage regulators

FOREWORD
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International Standard IEC 60076-21/IEEE Std C57.15 has been processed through IEC
technical committee 14: Power transformers.
The text of this standard is based on the following documents:
IEEE Std FDIS Report on voting
C57.15-2009 14/688/FDIS 14/697/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.
Published by the IEC under licence from IEEE. © 2009 IEEE. All rights reserved.

IEEE Std C57.15-2009
A list of all the parts in the IEC 60076 series, published under the general title Power
transformers can be found on the IEC website.

The committee has decided that the conten
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