Federal Pacific ventilated dry-type transformers incorporates wire and or strip wound coils in a barrel wound configuration. Horizontal and vertical spacers are strategically positioned in the windings to brace the winging layers and allow maximum ventilation. The electrical grade core steel is arranged in a construction designed to accommodate the coils.
The core and coil assembly is anchored to the enclosure through a vibration dampening system to reduce noise levels. Units through 600 kBA are provided with neoprene isolating pads while larger units are furnished with three layer rubber and cork pads. A flexible grounding conductor is installed between the core and coil assembly and the transformer enclosure.
Enclosures are rigidly braced and covers are fastened with slotted hex head screws for ease of removal. A rugged steel base supported by mounting feet opened outward provides safe handling with a fork lift and easy attachment to mounting pad.
Front accessible wiring compartments are approved for 90°C cable. Terminals are sized to carry the full current capacity of the transformers.
To attain UL listing, it was necessary to complete an accelerated aging test as specified by Underwriters Laboratories, Inc. This insulation system was subjected to a series of exposures to heat, vibration, moisture, and dielectric tests. As a proven system, this insulation system has received from Underwriters Laboratories, Inc. a recognized 200°C continuous rating. This total temperature of 220°C is derived from the average conductor temperature rise of 150°, hot spot temperature gradient of 30°C and an ambient temperature of 30°C.
The major components that allow for this 220°C rating are Nomex® paper, resin-glass laminates, silicon rubber, and polyester varnish. This combination of materials and the care taken in construction and workmanship, not only give these transformers a long operating life, but helps insure their quiet operation.
The design features of Federal Pacific transformers assures versatile, economical, and reliable distribution of power. All transformers are fully tested to insure trouble-free installation and operation. The unique combination of ratings makes the FH family suitable for a wide variety of applications.