Single Phase Pad - Mounted Distribution Transformers

2026-11-03

The purpose of these Specifications is to define the scope of supply for Single Phase Pad - Mounted Distribution Transformers that meet the minimum requirements as to quality , function , and capacity as outlined in the Special and Technical Provisions that follow . . 01 . 1 – STANDARDS All units shall meet the most recent editions of the following standards and all others that are applicable : Standard Number Standard Title DOE 10 CFR Part 431 Energy Conservation Standards for Distribution Transformers IEEE C57 . 12 . 00 General Requirements for Liquid - Immersed Distribution , Power , and Regulating Transformers IEEE C57 . 12 . 28 Pad - Mounted Equipment - Enclosure Integrity IEEE C57 . 12 . 35 Bar Coding for Distribution Transformers and Step - Voltage Regulators IEEE C57 . 12 . 38 Pad - Mounted - Type , Self - Cooled , Single - Phase Distribution Transformers ; High Voltage 34 500 GrdY / 19 920 V and Below ; Low Voltage , 240 / 120 V ; 167 kVA and Smaller IEEE C57 . 12 . 80 Terminology for Power and Distribution Transformers IEEE C57 . 12 . 90 Test Code for Liquid - Immersed Distribution , Power , and Regulating Transformers IEEE C57 . 91 Guide for Loading Mineral - Oil - Immersed Transformers IEEE C57 . 147 Guide for Acceptance and Maintenance of Natural Ester Fluids in Transformers ANSI Z535 Safety Sign and Label Standards ANSI / ISO / ASQ Q9001 Quality Management Systems - Requirements ASTM D - 3487 Mineral Insulating Oil Used in Electrical Apparatus ASTM D - 6871 Natural ( Vegetable Oil ) Ester Fluids Used in Electrical Apparatus Western Underground Committee Guide 2 . 13 Security for Pad - mounted Equipment Enclosures 2 . 02 - TRANSFORMER EFFICIENCY Only units that meet or exceed the U . S . Department of Energy efficiency standards for liquid filled distribution transformers 10 CFR Part 431 will be considered for this bid ; all others will be rejected . All units shall have represented efficiencies that meet or exceed the efficiency values in the following table : 2 . 03 - ENCLOSURE SPECIFICATIONS 2 . 03 . 1 – DIMENSIONS The maximum dimensions of the pad - mount transformers shall be as shown below . These dimensions do not include cooling fins . 2 . 03 . 1A – TYPE 1 TRANSFORMERS 25 – 50 kVA ( in .) 100 – 167 kVA ( in .) Height 32 . 5 38 . 5 Width 36 36 Depth 35 40 2 . 03 . 1B – TYPE 2 TRANSFORMERS 25 – 50 kVA ( in .) 100 – 167 kVA ( in .) Height 29 32 Width 36 36 Depth 35 40

Washington

2026-05-14