Combination transformers, commonly known as American box transformers, have excellent performance such as reliable power supply, reasonable structure, fast installation, flexibility, easy operation, and small size. They are widely used in various places such as industrial parks, residential areas, commercial centers, urban roads, and high-rise buildings. This type of product is different from the European box transformers currently produced in China in that: American box transformers integrate the transformer body, high-voltage load switches, and protection fuses and other equipment into the same tank, so they are smaller in size.