INTRODUCTION
Clause
1 Scope
2 Normative references
3 Definitions
4 General
5 Highest voltage for equipment and insulation level
6 Rules for some particular transformers
7 Insulation requirements and dielectric tests - Basic
rules
7.1 General
7.2 Insulation requirements
7.3 Dielectric tests
7.4 Insulation requirements and tests for the neutral
terminal of a winding
8 Tests on a transformers having a tapped winding
9 Repeated dielectric tests
10 Insulation of auxiliary wiring
11 Separate source AC withstand voltage test
12 Induced AC voltage tests (ACSD, ACLD)
12.1 General
12.2 Short-duration induced AC withstand voltage test
(ACSD) for transformers with uniformity insulated
high-voltage windings
12.3 Short-duration AC withstand voltage test (ACSD) for
transformers with non-uniformity insulated
high-voltage windings
12.4 Long-duration induced AC voltage test (ACSD) with
non-uniformity and/or uniformity insulated
high-voltage windings, according to table 1
13 Lightning impulse (LI) test
13.1 General
13.2 Test sequence
13.3 Test connections
13.4 Records of test
13.5 Test criteria
14 Test with lightning impulse chopped on the tail (LIC)
14.1 General
14.2 Chopping gap and characteristics of the chopping
14.3 Test sequence and test criteria
15 Switching impulse test (SI)
15.1 General
15.2 Test sequence and records
15.3 Test connections
15.4 Test criteria
16 External clearances in air
16.1 General
16.2 Bushing clearance requirements as determined by
transformer insulation withstand voltages
Annex A (Informative) Application guide for partial
discharge measurements during induced a.c.
withstand voltage test on transformers according
to 12.2, 12.3 and 12.4
Annex B (informative) Overvoltage transferred from the
high-voltage winding to a low-voltage winding
Annex C (informative) Information on transformer
insulation and dielectric tests to be supplied
with an enquiry an order
Annex D (normative) ACSD
Annex ZA (normative) Normative references to international
publications with their corresponding European
publications
Annex ZB (normative) Special national conditions