Specifications include, but are not limited to: Quantity: • 25kVA – Fifteen (15) transformers • 75kVA – Six (6) transformers Frequency: • 60 Hz Primary Voltage: • 7.2/12.47kV Ground Wye Secondary Voltage: • 120/240V System Voltage: • 12.47kV phase-to-phase nominal Standards: • C57.12.00 IEEE General Requirements for Liquid Immersed Distribution, Power and Regulating Transformers • C57.12.20 ANSI/IEEE Standard for Overhead-Type Distribution Transformers 500kVA or Smaller • C57.12.31 IEEE Standard for Pole-Mounted Equipment – Enclosure Integrity • C57.12.70 IEEE Standard for Standard Terminal Markings and Connections for Distribution and Power Transformers • C57.12.80 IEEE Standard Terminology for Power and Distribution Transformers • C57.12.90 IEEE Standard Test Code for Liquid-Immersed Distribution, Power, and Regulating Transformers • ASTM D3487 Standard Specification for Mineral Insulating Oil Use in Electrical Apparatus • US DOE – 2016, or newer, US Department of Energy efficiency standards for liquid-immersed medium-voltage distribution transformers Construction: • All transformer units shall be newly constructed and manufactured in North America. Repaired, rebuilt, or remanufactured units will not be accepted Ratings: • Primary and secondary ratings shall be as indicated in Request for Bids (RFB) • Primary basic lightning impulse insulation level (BIL) ratings shall be 95kV • Secondary BIL ratings shall be 30kV for all secondary voltages • Transformers shall be designed with an average winding rise
