Exterior Primary Fuse System for Transformer

Just about all of the electricity we use in our daily lives at our homes and offices pass through multiple transformers between the generating facility and its final location of utilization. In many cases the last transformer used is the common pole mounted transformer commonly seen upon power poles located between every few houses in a neighborhood. While for the most part these transformers are highly reliable and dependable, they are known to be easily taken out by nearby faults or lightning strikes. When this happens the most likely result is a blown primary fuse. However, this fuse is located on the interior of the transformer under oil, thus forcing a complete emergency transformer replacement in the field, and a rebuild in a shop. This means extended outage times for what is a simple blown fuse. Accordingly, there exists a need for a means by which primary fusing on pole mounted transformers can be easily replaced without creating more work for the power company and aggravation for the residents.  

Inventors Mike Martinez, Brian Brownlow & Randy McFall of Lakeside, Arizona have addressed this need by developing an externally-replaceable, oil-immersed, primary fuse device for an electrical power distribution transformer for eliminating a need for a fuse inside of a transformer by utilizing an externally replaceable fuse.

The Exterior Primary Fuse System for Transformer is an apparatus and method of utilizing an externally-replaceable primary fuse for a pole-mounted electrical distribution transformer, thereby eliminating the need for a conventional internal fuse. The fuse is accessed using a bayonet-style fuse holder mounted to the outside surface of a transformer tank, being internally wired to a primary transformer lead. The fuse would remain immersed in oil like its conventional counterpart during use. The fuse-holding apparatus permits fuse replacement while the transformer remains mounted to a pole which reduces down time and service expense. The use of the Exterior Primary Fuse System for Transformer allows for quick and easy primary fuse replacement in a manner that is more convenient for both the worker and the resident.