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Reference EN 60076-3:2013
Title Power transformers - Part 3: Insulation levels, dielectric tests and external clearances in air
Project Number 24097
Abstract/Scope IEC 60076-3:2013 specifies the insulation requirements and the corresponding insulation tests with reference to specific windings and their terminals. This International Standard applies to power transformers as defined by IEC 60076-1. It also recommends external clearances in air. It gives details of the applicable dielectric tests and minimum dielectric test levels. Recommended minimum external clearances in air between live parts and between live parts and earth are given for use when these clearances are not specified by the purchaser. For categories of power transformers and reactors which have their own IEC standards, this standard is applicable only to the extent in which it is specifically called up by cross reference in the other standards. This third edition of IEC 60076-3 cancels and replaces the second edition published in 2000, and constitutes a technical revision. The main changes from the previous edition are as follows: - Three categories of transformer are clearly identified together with the relevant test requirements, these are summarised in Table 1. - Switching impulse levels are defined for values of Um > 72,5 kV. - The procedure for Induced voltage tests with PD has been revised to ensure adequate phase to phase test voltages. - The AC withstand test has been redefined (LTAC instead of ACSD). - Induced voltage tests are now based on Ur rather than Um. - New requirements for impulse waveshape (k factor) have been introduced. - Tables of test levels have been merged and aligned with IEC 60071-1:2010. - Additional test levels have been introduced for Um > 800 kV. - A new Annex E has been introduced, which sets out the principles used in assigning the tests, test levels and clearances in air.


Current Stage code 6060
Current Stage code date 2013-11-29
Current Stage code deadline 2014-06-04
Deadline date for vote  


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IEC Technical Body IEC/TC 14
Reference Document IEC 60076-3:2013 (EQV)
ICS 29.180 - Transformers. Reactors
Keywords Transformer; Power transformer; Insulation level; Dielectric test; Clearance in air
Note Will supersede EN 60076-3:2001 * 2013-08-13 - Publication allocated to
Special National Condition(s)  


Categories - Aspects
Product Life Cycle


Deadline Date
6060 2013-11-29 2014-06-04 export to doc file  EN  FR  DE
5099 2013-09-04 2013-10-02  
5060 2013-05-06 2013-05-27 export to doc file  EN
5020 2013-03-01 2013-05-03  
3090 2013-02-26 2013-03-01  
5060 2012-08-13 2012-09-03 export to doc file  EN
5020 2012-03-09 2012-08-10  
1090 2012-03-06 2012-03-09  

Implementation Dates

date of Ratification (DOR) (1) 2013-09-04
date of Availability (DAV) (2) 2013-11-29
date of Announcement (DOA) (3) 2013-12-04
date of Publication (DOP) (4) 2014-06-04
date of Withdrawal (DOW) (5) 2016-09-04


Supersedes EN 60076-3:2001
Superseded by  
Normative reference (6) IEC 60050-421
EN 60060-1:2010
EN 60060-2:2011
EN 60071-1:2006
EN 60076-1:2011
EN 60137:2008
EN 60270:2001

(1) Date of ratification (dor) date when the Technical Board notes the approval of an EN (and HD for CENELEC), from which time the standard may be said to be approved

(2) Date of availability (dav) date when the definitive text in the official language versions of an approved CEN/CENELEC publication is distributed by the Central Secretariat

(3) Date of announcement (doa) latest date by which the existence of an EN (and HD for CENELEC), a TS or a CWA has to be announced at national level

(4) Date of publication (dop) latest date by which an EN has to be implemented at national level by publication of an identical national standard or by endorsement

(5) Date of withdrawal (dow) latest date by which national standards conflicting with an EN (and HD for CENELEC) have to be withdrawn

(6) This list of normative references is purely indicative. The only official list of normative reference is the list of the published standard.