AS 2735-1984

1 - AS 2735-1984 DRY-TYPE POWER TRANSFORMERS
4 - PREFACE
4 - CONTENTS
5 - SECTION 1. SCOPE AND GENERAL
5 - 1.1 SCOPE.
5 - 1.2 APPLICATION.
5 - 1.3 REFERENCED DOCUMENTS.
5 - 1.4 SERVICE CONDITIONS.
5 - 1.4.1 Normal service condi tions.
5 - 1.4.2 Provision for unusual service conditions.
5 - 1.5 DEFINITIONS.
6 - 1.5.1 General.
6 - 1.5.2 Terms relating to the containment of a dry-type transformer.
6 - 1.6 TAPPINGS AND CONNECTIONS.
6 - 1.6.1 General.
6 - 1.6.2 Tapping range.
6 - 1.6.3 Connections.
6 - 1.7 REQUIREMENTS WITH REGARD TO ABILITY TO WITHSTAND SHORT-CIRCUIT.
7 - SECTION 2. RATING
7 - 2.1 GENERAL.
7 - 2.2 RATED POWER.
7 - 2.3 PREFERRED VALUES OF RATED POWER.
7 - 2.4 OPERATION OF HIGHER THAN RATED VOLTAGE.
7 - 2.5 RATING PLATES.
7 - 2.5.1 General.
7 - 2.5.2 Information to be given in all cases.
7 - 2.5.3 Information to be given for sealed units only.
8 - SECTION 3. COOLING METHODS AND TEMPERATURE RISE
8 - 3.1 IDENTIFICATION ACCORDING TO COOLING METHOD.
8 - 3.1.1 Identification symbols.
8 - 3.1.2 Arrangement of symbols.
8 - 3.2 TEMPERATURE-RISE LIMITS.
8 - 3.2.1 Normal temperature-rise limits.
8 - 3.2.2 Reduced temperature rises for transformers designed for high cooling air temperatures or special air coding conditions.
8 - 3.2.3 Reduced temperature rises for transformers designed for high altitudes.
10 - SECTION 4. INSULATION LEVELS
10 - 4.1 INSULATION LEVELS.
10 - 4.1.1 General.
10 - 4.1.2 Transformers for use at high altitudes.
11 - SECTION 5. TESTS
11 - 5.1 GENERAL REQUIREMENTS FOR TYPE, ROUTINE AND SPECIAL TESTS.
11 - 5.1.1 General.
11 - 5.1.2 Measurement of winding resistance (routine test)
11 - 5.1.3 Measurement of voltage ratio and check of voltage vector relationship (routine test).
11 - 5.1.4 Measurement of impedance voltage (principal tapping) short-circuit impedance and load loss (routine test).
11 - 5.1.5 Measurement of no-load loss and current (routine test).
11 - 5.1.6 Separate-source voltage withstand test (routine test).
11 - 5.1.7 Induced overvoltage withstand test (routine test).
11 - 5.1.8 Lightning impulse test (type test).
11 - 5.1.9 Partial discharge measurement.
12 - 5.1.10 Temperature-rise test (type test).
13 - 5.1.11 Winding temperature-rise correction for reduced current.
13 - 5.1.12 Determination of constant temperature conditions.
13 - 5.2 MEASUREMENT OF SOUND LEVEL (SPECIAL TEST).
13 - 5.3 SHORT-CIRCUIT TEST (SPECIAL TEST).
13 - 5.4 MEASUREMENT OF ZERO SEQUENCE IMPEDANCE (SPECIAL TEST).
13 - 5.5 TOLERANCES.
14 - SECTION 6. ENCLOSURES
14 - 6.1 DEGREE OF PROTECTION PROVIDED BY ENCLOSURES.
15 - APPENDIX A - INFORMATION REQUIRED WITH ENQUIRY AND ORDER
15 - A1 RATING AND GENERAL DATA.
15 - A1.1 Normal.
15 - A1.2 Special.
16 - A2 PARALLEL OPERATION.
16 - A3 TESTS.
17 - APPENDIX B - UNUSUAL ENVIRONMENTAL CONDITIONS

Specifies requirements for dry-type power transformers (including autotransformers) having highest voltage for equipment values up to and including 36 kV. This Standard should be read in conjunction with AS 2374, Power transformers. Where Australian Standards do not exist for other particular power transformers, This Standard may be applicable as a whole or in parts.

This standard specifies requirements for dry-type power transformers (including auto-transformers) having highest voltage for equipment values up to and including 36 kV.The following small and special dry-type transformers are not covered by this standard:(a) Single-phase transformers rated at less than 1 kV.A and polyphase transformers rated at less than 5 kV.A.(b) Instrument transformers (covered by AS 1243 and AS 1675).(c) Transformers for semiconductor converters (AS 1955).(d) Starting transformers.(e) Testing transformers.(f) Traction transformers mounted on rolling stock.(g) Flameproof transformers.(h) Welding transformers.(j) Voltage regulating transformers.(k) Small power transformers in which safety is a special consideration.Where Australian standards do not exist for the transformers mentioned above or for other special transformers, this standard may be applicable as a whole or in parts.

Reconfirmed 1994