EN 50708-1-1:2020

SLOVENSKI STANDARD
01-julij-2020
Nadomešča:
SIST EN 50588-1:2017
SIST EN 50629:2015
SIST EN 50629:2015/A1:2016
SIST EN 50629:2015/A2:2018
Močnostni transformatorji - Dodatne evropske zahteve - 1-1. del: Skupni del -
Splošne zahteve
Power transformers - Additional European requirements: Part 1-1: Common part -
General requirements
Transformateurs de puissance - Exigences européennes supplémentaires : Partie 1 -
Partie commune
Ta slovenski standard je istoveten z: EN 50708-1-1:2020
ICS:
29.180 Transformatorji. Dušilke Transformers. Reactors
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 50708-1-1

NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2020
ICS 29.180 Supersedes EN 50588-1:2017 (PART), EN 50629:2015
(PART) and all of its amendments and corrigenda (if any)
English Version
Power transformers - Additional European requirements: Part 1-
1: Common part - General requirements
Transformateurs de puissance - Exigences européennes To be completed
supplémentaires : Partie 1 - Partie commune
This European Standard was approved by CENELEC on 2019-10-09. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 50708-1-1:2020 E
Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Service condition . 10
5 Ratings and general requirements . 11
5.1 Rated power . 11
5.2 Rated frequency . 11
5.3 Energy performance . 11
5.3.1 Energy performance requirements . 11
5.3.2 Exclusion from energy performance requirements . 11
5.3.3 Reference conditions . 12
5.3.4 Technical documentation . 12
6 Rating plate . 13
7 Tolerances . 13
7.1 Tolerance during factory acceptance tests . 13
7.2 Tolerances for Market surveillance. 14
8 Tests . 14
8.1 General . 14
8.2 Measurement of cooling consumption . 14
9 Accessories and fittings . 14
10 Capitalization of losses . 14
11 Transformer overhaul . 15
Annex A (normative) Peak efficiency calculation . 16
A.1 Efficiency Index. 16
A.2 Peak Efficiency Index . 16
A.3 PEI calculation for transformers having more than two windings . 17
Annex B (informative) Capitalization of losses . 19
B.1 General Theory, Concept of Capitalization . 19
B.2 Impact of capitalization values . 19
B.3 Capitalization formula . 20
B.3.1 General . 20
B.3.2 Calculation of factor A . 20
B.3.3 Calculation of factor B . 21
B.3.4 Use of A and B for tender evaluation. 23
B.3.5 Determination of factors A and B . 24
Annex C (informative) A-deviations . 26
Annex D (informative) Additional considerations related to energy performances. 27
D.1 General . 27
D.2 Autotransformers . 27
D.3 Voltage and insulation level . 27
D.4 More than two windings. 27
D.5 Short-circuit impedance . 27
D.6 Tapping range . 27
D.7 Losses on taps different than rated tap . 28
D.8 Separate phases . 28
Annex E (informative) Transformer overhaul . 29
E.1 General . 29
E.1.1 Overview . 29
E.1.2 Energy performance. 29
E.1.3 Life expectancy . 29
E.2 Classification of overhaul activities . 29
E.2.1 Overview . 29
E.2.2 Repair. 30
E.2.3 Upgrade . 30
E.2.4 Refurbishment . 30
E.2.5 Retrofit . 31
Annex ZZ (informative) Relationship between this European Standard and the ecodesign
requirements of Commission Regulation (EU) No 548/2014 of 21 May 2014 and its
amendment No 2019/1783 of 1 October 2019 on implementing Directive 2009/125/EC of
the European Parliament and of the Council with regard to small, medium and large

power transformers aimed to be covered . 32
Bibliography . 33

European foreword
This document (EN 50708-1-1:2020) has been prepared by CLC/TC 14, “Power transformers”.
The following dates are fixed:
• latest date by which this document has (dop) 2020-11-22
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2023-05-22
standards conflicting with this document
have to be withdrawn
This document supersedes EN 50588-1:2017 and EN 50629:2015 and all of their amendments and corrigenda
(if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a mandate given to CENELEC by the European Commission and the
European Free Trade Association, and supports essential requirements of Commission Regulation (EC).
For the relationship with the Commission Regulation (EC) see informative Annex ZZ, which is an integral part
of this document.
Introduction
The EN 50708 series, “Power transformers – Additional European requirements” has been prepared by
CENELEC TC 14 to address specific European requirements of power transformers related EU Regulations
and local practices.
Technical requirements set by the EN 50708 series supplement, modify or replace certain requirements of the
other EN standards derived from equivalent IEC international standards.
This series contains general requirements on energy performance, accessories, fittings, tests, mechanical
requirements etc. structured as follows:
— Part 1 series - Common requirements;
— Part 2 series - Medium power transformers;
— Part 3 series - Large power transformers.
The EN 50708-X parts with X greater than 1 contain particular requirements for a different category of
transformers or transformer applications which are based on the requirements of the general parts of
EN 50708-1-1.
The EN 50708-X parts should be considered in conjunction with the requirements of the general part.
The particular requirements of these subparts of EN 50708 supplement, modify or replace certain requirements
of the general parts of EN 50708-1-1 and/or EN 50708-1-X being valid at the time of pub
...