American-style box-type substation, mainly with a triangular layout (or "pin-shaped" structure), is a transformer that combines the transformer body, switchgear, fuses, tap changers, low-voltage distribution devices and other corresponding auxiliary equipment. It can meet various configuration requirements of users such as electric energy metering, reactive power compensation, and low-voltage shunting. American-style box-type substations can be used outdoors as well as indoors. They are widely applicable to various places such as industrial parks, urban residential quarters, commercial centers, road lighting systems, high-rise buildings and temporary construction sites. Their advantages are: environmental protection, small floor space and convenient installation.