This standard specifies the terms and definitions, product classification and model, operating environment temperature, technical requirements, testing and marking, lifting, packaging, transportation, and storage of underground transformers. This standard applies to single-phase and three-phase underground transformers with voltage levels of 20kV and below, rated frequency of 50Hz, liquid immersed type, and rated capacity of 30 kVA~2500 kVA. Note: Other underground transformers can refer to this standard. The following normative references are essential for the application of this document. For dated references, only the dated version applies to this document. For undated references, the latest version (including all modification orders) applies to this document. GB/T 1094.1-2013 Power Transformers Part 1: General Provisions GB/T 1094.2 Power Transformers Part 2: Temperature Rise of Liquid Immersed Transformers GB/T 1094.3 Power Transformers Part 3: Insulation Levels Insulation Testing and External Insulation Air Gap GB/T 1094.5 Power Transformers Part 5: Ability to withstand short circuits GB/T 1094.7 Power Transformers Part 7: Load Guidelines for Oil Immersed Power Transformers GB/Z 1094.14 Power Transformers Part 14: Design and Application of Liquid Immersed Power Transformers Using High Temperature Insulation Materials GB/T 2900.95 Electrotechnical Terminology Transformers Voltage Regulators and Reactors GB/T 6451 Technical Parameters and Requirements for Oil Immersed Power Transformers GB/T 25289 Technical Parameters and Requirements for 20kV Oil Immersed Distribution Transformers GB/T 25438 Technical Parameters and Requirements for Three-phase Oil Immersed Solid Coil Iron Core Distribution Transformers GB/T 25446 Technical Parameters and Requirements for Oil Immersed Amorphous Alloy Iron Core Distribution Transformers JB/T 501 Test Guidelines for Power Transformers JB/T 3837 Method for Compiling Transformer Product Models JB/T 10217-2013 Combined Transformers JB /Technical parameters and requirements for T 10317 single-phase oil-immersed distribution transformer
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