This type of transformer is also called the European box substation; it is the combination of the high-voltage equipments, transformer, and low voltage transformer equipments and therefore is widely used in the skyscraper, residential districts, urban and rural construction, hi-tech development zone, small and medium size enterprise, mine and oil fields and the temporary construction sites to receive and distribute the power. The product has the features of strong complete sets, small size, compacted structure, running safely, easy maintenance, and mobile. And it only takes the 1/10-1/5 of the space of the same capacity of civil construction distribution, and therefore greatly reduces the construction cost. It can be used as the ring network distribution system in the distribution system and can be also used for dual-supply distribution system or radiator terminal distribution system. It is fully in accordance with the standard of SD320-1992 (the technology of Boxes substation) and the standard of GB/T 17467-1998 (high voltage chuan type prefabricated substation). The shell is made of non-metal, composite board or the steel sheet according to the requirements of the users.