Specifications include, but are not limited to: Capacities and Characteristics: 1. Self-Cooled Rating, Class ONAN. Comply with IEEE C57.12.00 for cooling class. 2. Power Rating (kVA): As specified herein, and as shown on Drawings. 3. Primary Voltage Ratings: 12,470GrdY/7,200V, three-phase, 60-Hz. 4. Secondary Voltage Ratings: 480GrdY/277V and 208GrdY/120V, 60-Hz as shown on Drawings. 5. Taps: Comply with IEEE C57.12.26 requirements. a. 480GrdY/277V Units: Full capacity, two 2-1/2 percent below and two 2- 1/2 percent above, rated voltage. b. 208GrdY/120V Units: Full capacity, four 2-1/2 percent below rated voltage. c. Externally operated no-load tap changer. d. Provisions for locking handle in any position. 6. Transformer BIL (kV): Comply with IEEE C57.12.26 requirements. a. Primary: 95-kV BIL. b. Secondary: 30-kV BIL (600V or less).
