Specifications include, but are not limited to: Transformers shall be three-phase, pad-mounted distribution type, 60 hertz, liquid immersed, selfcooled, suitable for outdoor service and shall be furnished complete with High-fire point Fluid(FR3); Transformers shall be rated 1240Y/7200 – 750 kVA, 277/480 volts, 60 hertz, 95 KV BIL with four 2½% taps 2 above and 2 below nominal voltage. Transformer shall have an average winding rise not exceeding 65 degrees Centigrade. KVA ratings shall be as specified in the proposal section at the end of this schedule.; Transformer shall come complete with load break inserts with latch indications. Primary connections shall be arranged for loop-feed. Transformer shall have three insulated secondary bushings and one grounded secondary neutral bushing, with copper ground strap installed. Secondary bushings shall have Ten-Hole spade type terminals supported from the top of compartment with NEMA standard hole spacing. There shall be a parking stand for each primary bushing.; Transformer shall be Wye connected, with internal grounding of the primary neutral, and shall have a five-legged core or other means of avoiding tank heating due to third harmonics. Two high voltage and one low voltage ground pads shall be provided on tank.; Transformer shall be equipped with three primary liquid-immersed dual-sensing, externally replaceable, expulsion type load break fuses with flapper valve in series with internal current limiting fuses, with provision for hot stick removal. Transformer shall also be equipped with a pressure-vacuum gauge, thermometer, liquid level gauge, oil drip shield, oil fill plug, 1” oil drain valve, and a pressure relief device. The tank will be constructed to withstand a minimum of 12 psig without rupture.; Transformer shall be dead-front primary type with separate high- and low-voltage compartments and removable front sill. The high-voltage compartment shall be fastened from inside the lowvoltage compartment, and the low-voltage compartment shall have provision for padlocking. The unit shall be suitable for installation without a fence or other protective enclosure.; 1. Salt spray (relates to coastal environments and/or presence of snow-melting salts or fertilizers).: Scribe to bare metal and test for 1000 hours in 5% salt spray per ASTM B-117. Loss of adhesion from bare metal should not extend more than 1/8" from the scribe. Under-film corrosion should not extend more than 1/16" from the scribe.; 2. Crosshatch adhesion (relates to adhesion after scratching of the finish): Scribe to bare metal a crosshatch pattern and test per ASTM D 3359, latest revision. Use Method A for films thicker than 5 mils. And Method B for films less than or equal to 5 mils. There shall be 100% adhesion to the bare metal and between layers.; 3. Humidity (relates to environments with high humidity): Test for 1000 hours subject to 98% humidity at 45 degrees C ± 1-degree C per ASTM D-2247. There should be no blisters.
