My friends should all know that the civilian voltage in our country is 220V. Maybe some friends who have been to Japan or the United States also know that their civilian voltage in the United States and Japan is 110V, so what’s the matter? In fact, in general, the voltage in the world can be divided into 220V area and 110V area. At present, more than 120 countries use 220V voltage, and more than 30 countries use 110V voltage. There are also some countries where two voltage specifications exist simultaneously.
In fact, my country did not have a unified standard when it began to use alternating current in the late Qing Dynasty. The specifications were also varied. It was not until 1930 that the National Government announced that the Chinese voltage standard was 220V. In the United States, Edison’s General Electric Company was the first to supply customers. The direct current is 110V, and it has been used since then. In Japan, influenced by the United States, 110V is also used in the voltage.
Compared with the two voltages, from a safety point of view, 110 is safer than 220V, but both are fatal to human injuries. In actual operation, the disadvantages of 110V voltage are more obvious than 220V voltage. First of all, when the same power is delivered, 220V has less loss than 110V, and considering the actual route interference and loss, 220V high-voltage power transmission is farther, in fact, the voltage is doubled, and the cross-sectional area of the wire can be saved by half. Power lines.
In addition, the frequency of 220V and 50 Hz is lower than the frequency of 110V and 60 Hz, and the power of the motor is smaller and the materials used to manufacture the motor are saved. In fact, the United States has also considered changing the 110V voltage to 220V, but because domestic people are accustomed to using 110V voltage, and the electrical appliances in the home are all 110V, it is relatively difficult to adjust. So the progress of replacing the voltage is slow. However, the United States has not given up its efforts. They have now developed a two-way power supply method, where citizens can choose their own voltage according to the power of electrical appliances.