There are two types of voltages used in indoor electricity in the world, ranging from 100V to 130V and 220 to 240V. 100V, 110 ~ 130V are classified as low voltage, such as the United States, Japan and other voltages on board, pay attention to safety; 220 ~ 240V is called high voltage, including 220 volts in China and 230 volts in the United Kingdom and many European countries, The focus is on efficiency. In countries with 220-230V voltage, there are also cases where 110-130V voltage is used, such as Sweden and Russia.