Real estate high-rise buildings require: according to the \"Civil Building Electrical Design Specification\" (JGJ / T16-92) 3.1 stipulates that many parts of the high-rise building are one-stage load, such as one, two-level hotel banquet hall, Cascare, room, kitchen, important office building, main office, meeting room lighting, large department store business hall lighting; there are some parts of the secondary load, such as the escalator of department stores, ladder Main offices of electricity, department, provincial office building, meeting room lighting, etc. The first-level load also contains a particular important load, such as important transportation hubs, communication hubs, and public places such as public places such as large number of people who are often used for important international activities. The primary load should be co-electricity by two power supplies. Secondary load is also advisable to supply power from two loops when conditions allow for the conditions, especially the secondary load of fire-fighting electricity, should follow the two back to the secondary load.