American industrial electricity voltage?

American industrial voltage standard (ANSI C84-la- 1980) stipulates that:

Electricity is a three-phase four-wire system with a voltage range of 227 V-480 V; When there is lighting: 440 ~ 500 V at the electrical equipment; The power supply point is 456 ~ 504 V, and when there is no license, it is 432 ~ 500 V at the electrical equipment; Power supply point 456 ~ 504 v.

The United States was the first country to popularize electricity, and the household voltage used was 1 10v, because the engine at that time could not generate such a large voltage. The United States is the country with the most developed power industry in the world. The voltage standard (ANSI C84-la- 1980) is adopted. The focus of electrical protection is fire prevention.

Extended data:

The voltage level in the United States is rather complicated, with eight voltage levels (i.e. 765,500,345,287.5,230,11,138) from10 to 765 kV * *. According to the nine cooperation zones, five cooperation zones (MAAC, SERC, Marca, SWPP and WSCC) adopt 500/345(230)/ 138 series, and three cooperation zones (NPCC, ECAR and Main) adopt 765/345 (230)/65438.

The longest 500 kV line is the West Coast Pacific Link, with a total length of 1.520 km. There are two * * lines, which send northwest hydropower to southwest California load center, and a 400 kV DC line is parallel to it, with a transmission capacity of nearly 4 million kilowatts. The total length of 500 kV lines in the United States has reached 36,000 kilometers, which together with 70,000 kilometers of 345 kV lines constitute the main trunk line of the American power system.

In addition, there are more than 3,000 kilometers of 765 kV lines in the three cooperation zones of East, Central and Northeast China, most of which are concentrated in the AEP (American Power Company) system of ECAR. These 765 kV lines are characterized by short-distance and large-capacity transmission, mainly to send power from mine power plants and nuclear power plants to load centers.

Reference: Baidu Encyclopedia-American Power Industry