Why are household voltages different in different countries?

The advantages of high voltage are low loss and high power. The application range of general small household appliances is 100-240V, and the problem of plus or minus 20 V of household appliances is not great. In fact, 1 10 V is just as unsafe as 220 V, so you have to charge it if you don't pay attention to it, and 36 V is useless ~ ~ Also, with the colonial rule, the voltage varies from country to country in the world, which is roughly100-120,200-230. Industrial voltage, such as China 240, is higher than domestic voltage, because industry needs more electricity. The voltage problem is like driving on the left and driving on the right. . . It can be traced back to the tradition of riding a horse and driving a carriage. . . The main reason is preconceived ideas.

The earliest frequency of commercial alternating current is 60Hz, and the voltage is 1 10V. Its inventor, nikola tesla, was an American (immigrant) and invested by the boss of Westinghouse Electric Company, and put into commercial AC power grid for the first time in the United States. The United States adopts English units, and for the convenience of calculation, the specification of 60Hz/ 1 10V is adopted.

After the success of commercial AC TV University, Europe quickly introduced AC power generation and feed technology. Europe uses metric units except Britain. For the convenience of calculation, the frequency is changed to 50Hz. Later, because of the low voltage of 1 10V, the transmission loss of the power grid is large. In order to improve this situation, in European countries where there is no large-scale construction of AC power grid and no "burden", the voltage specification of 220V is adopted, which is derived from the voltage of110 V. The technical transformation is relatively simple, so 220V is formed in European countries.

There is no uniform standard for the earliest AC power grid in China, which is only a local small power grid with various specifications and equipment provided by developed industrial countries. After China's basic reunification, the metric system was chosen as the standard of weights and measures in China, so the power grid construction began to turn to the metric system. After 1949, China's industrialization turned to the Soviet model in an all-round way, and the power grid construction also followed Soviet standards, and the Soviet Union also adopted European standards, so 220V/50Hz was finally set as the China power grid standard. Due to historical reasons, the voltage standard of 1 10V was used in some former concessions in Northeast China and Shanghai, and it was not until the end of 1960s that the voltage of 220V was uniformly used.

Sunday, February 23rd, 2007 15:36 The voltage difference among countries15: 36 At present, there are two kinds of voltages used for indoor electricity in the world, namely 100 V ~ 130 V and 220 ~ 240 V.

100V,1/kloc-0 ~130V belong to low voltage, such as the voltage in America and Japan. And the voltage on board. So its equipment is designed according to such a low voltage, pay attention to safety;

220 ~ 240 V is considered as high voltage, including 220 V in China and 230 V in Britain and many European countries. The emphasis is on efficiency.

The following is an overview:

100 volts is only applicable to 2 countries.

Japan, Korea

1 10 ~ 130 V about 30 countries.

China, Taiwan Province, USA, Canada, Panama, Cuba, Lebanon, Mexico, etc.

220 ~ 230 V is about 120 country.

Britain, Germany, France, China, Singapore, Hong Kong (200V), Italy, Spain, Greece, Austria, Netherlands, Philippines, Thailand, Norway, Singapore, India, New Zealand and Australia.

Note: 1: In countries where the voltage is 220 ~ 230 V, there are also cases where the voltage of 1 10 ~ 130 V is combined according to regional needs, such as Sweden and Russia.

If it is changed, all the previously designed appliances will not be used, or a transformer will be added.