2.2 PAD-MOUNTED, LIQUID-FILLED TRANSFORMER A. Description: Complying with: C57.12.00; C57.12.34; C57.12.28; C57.12.70; C57.12.80; C57.12.90; C57.91; NEMA TR 1-1993 (R2000); NEMA 260-1996 (2004); and 10 CFR Part 431. B. Insulating Liquid: Less Flammable, edible-seed-oil based, and UL listed as complying with NFPA 70 requirements for fire point of not less than 300 deg C when tested according to ASTM D 92. Liquid shall be biodegradable and nontoxic. C. Insulation Temperature Rise: 65 deg C, based on an average ambient temperature of 30 deg C over 24 hours with a maximum ambient temperature of 40 deg C. D. Conductor: Copper Windings. E. Basic Impulse Level: 95kV. F. Full-Capacity Voltage Taps: Four 2.5 percent taps, 2 above and 2 below rated high voltage; with externally operable tap changer for de-energized use and with position indicator and padlock hasp. G. High Voltage Over-current Protection; 1. Fuses: 150-kV fuse assembly. Rating of current-limiting fuses shall be 50-kA RMS at 15.5 kV. a. Bay-O-Net high ampere overload with paralleling current limiting fuse. H. High Voltage Terminations and Equipment. 1. 15 KV Dead-front currents below 200 amps: The high voltage bushings shall be 15 kV 200A bushing wells with bushing well inserts installed. The bushings shall be externally removable and be supplied with a removable stud. 2. The transformer shall be provided with six (6) high voltage bushings in for radial feed configurations. The bushing heights shall be in accordance with Figure 6, dimensions, of ANSI C57.12.34. 3. Bushing-Well Inserts: One for each high-voltage bushing well. 4. Surge Arresters: Dead-front, elbow-type, metal-oxide-varistor units. 5. Parking Stands: One for each high-voltage bushing well. 6. Portable Insulated Bushings: Arranged for parking insulated, high-voltage, load-break cable terminators; one for each primary feeder conductor terminating at transformer. I. Accessories: 1. Drain Valve: 1 inch, with sampling device. 2. Dial-type thermometer. 3. Liquid-level gage. 4. Pressure-vacuum gage. 5. Pressure Relief Device: Self-sealing with an indicator
