scope:

This specification covers oil-filled, pad-mounted, compartmental-type transformers designed in general to comply with the requirements of ANSI standards C57.12.00, C57.12.25 and C57.12.26. These transformers are designed for outdoor installation over a concrete vault or similar structure to provide underground power distribution to FAA facilities via a three-phase, four-wire loop distribution system at various distribution voltages (high voltage hot to exceed 25kV, three-phase, line to line). The transformers shall be either single or three-phase, with primary and secondary wiring connections as specified in 1.1 and as indicated in Figures 1 and 2. All transformers shall be configured for loop-feed connections as shown herein. In addition, if requested by the purchaser, the transformers shall include switches meeting the requirements specified here in on the loop-feed connections as shown in Figures 1 and 2.