What is a AC power supply?

An AC power supply refers to a power source where the current alternates its direction periodically. Alternating Current (AC) is the flow of electric charge that changes direction at regular intervals, and it is the most common form of power used in households and industries. AC power is the primary form of electricity generated at power plants and is used for commercial electricity distribution. The main feature of AC power is that the current’s direction and magnitude change over time. This characteristic makes it highly efficient for power transmission. By transmitting power at high voltages, energy losses are minimized, allowing for long-distance transmission. Additionally, AC power can be easily stepped up or down in voltage using transformers, which enhances the efficiency of energy distribution.

Most electrical devices used in homes, commercial buildings, and factories rely on AC power. Examples include household appliances (televisions, refrigerators, air conditioners) and industrial machinery and lighting systems. In Japan, the commercial AC supply operates at frequencies of either 50Hz or 60Hz, with voltages of 100V or 200V being typical. The frequency of electricity varies depending on the region, with East Japan using 50Hz and West Japan using 60Hz.

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