IEC 60076-11 : 1.0

FOREWORD
1 Scope
2 Normative references
3 Definitions
4 Service conditions
    4.1 General
    4.2 Normal service conditions
    4.3 Electromagnetic compatibility (EMC)
    4.4 Provision for unusual service conditions
    4.5 Transport and storage conditions
5 Tappings
6 Connections
7 Ability to withstand short circuit
8 Rating
    8.1 General
    8.2 Rated power
    8.3 Preferred values of rated power
    8.4 Operation at higher than rated voltage
    8.5 Operation with fan cooling
    8.6 Operation in an enclosure
9 Rating plate
    9.1 Rating plate fitted to the transformer
    9.2 Rating plate fitted to the transformer enclosure
10 Identification according to cooling method
    10.1 Identification symbols
    10.2 Arrangement of symbols
11 Temperature-rise limits
    11.1 Normal temperature-rise limits
    11.2 Reduced temperature rises for transformers designed
         for high cooling air temperatures or special air
         cooling conditions
    11.3 High altitude temperature rise correction
12 Insulation levels
    12.1 General
    12.2 Transformers for use at high altitudes
13 Climatic, environmental and fire behaviour classes
    13.1 Climatic classes
    13.2 Environmental classes
    13.3 Fire behaviour classes
    13.4 Test criteria for climatic, environmental and fire
         behaviour classes
14 General requirements for tests
15 Measurement of winding resistance (routine test)
16 Measurement of voltage ratio and check of phase displacement
    (routine test)
17 Measurement of short-circuit impedance and load loss
    (routine test)
18 Measurement of no-load loss and current (routine test)
19 Separate-source AC withstand voltage test (routine test)
20 Induced AC withstand voltage test (routine test)
21 Lightning impulse test (type test)
22 Partial discharge measurement (routine and special test)
    22.1 General
    22.2 Basic measuring circuit (typical only)
    22.3 Calibration of the measuring circuit
    22.4 Voltage application
    22.5 Partial discharge acceptance levels
23 Temperature-rise test (type test)
    23.1 General
    23.2 Methods of loading
    23.3 Winding temperature-rise correction for reduced current
    23.4 Determination of steady state conditions
24 Measurement of sound level (special test)
25 Short-circuit test (special test)
26 Environmental test (special test)
    26.1 General
    26.2 Validity of the test
    26.3 Testing procedure
27 Climatic test (special test)
    27.1 Thermal shock test (special test)
    27.2 Validity of the test
    27.3 Thermal shock test for C1 class transformers
    27.4 Thermal shock test for C2 class transformers
28 Fire behaviour test (special test)
    28.1 General
    28.2 Checking of corrosive and harmful gases emission
    28.3 Fire behaviour test for F1 class transformer
    28.4 Quantities to be measured and measuring devices
    28.5 Calibration of the test chamber without test object
    28.6 Test method
    28.7 Test report
    28.8 Criteria for evaluating the test results
29 Tolerances
30 Protection against direct contact
31 Degrees of protection provided by enclosures
32 Earthing terminal
33 Information required with enquiry and order
Annex A (informative) Installation and safety of dry-type
                      transformers
Figures
Tables

Applicable to dry-type power transformers (including auto- transformers) having values of highest voltage for equipment up to and including 36 kV and at least one winding operating at greater than 1,1 kV. It applies to all construction technologies.