What is the frequency of alternating current (AC) used in the United States?

The frequency of alternating current (AC) used in the United States is 60 Hz. This standard has been in place for many decades and is crucial for the consistent operation of electrical devices and systems throughout the country. The choice of 60 Hz for AC transmission was largely influenced by early electrical engineering practices and has become integral to the infrastructure that supports commercial and residential power supply.

In practical terms, this means that the current changes direction 60 times per second in the electrical grid. Many household appliances, industrial machines, and other electrical devices are designed to operate on this frequency, ensuring optimal performance and reliability. Variations from this frequency can lead to inefficiencies and potential damage to electrical equipment designed specifically for 60 Hz operation.

While other countries may utilize different frequencies, such as 50 Hz commonly found in Europe, the standardization of 60 Hz in the U.S. aligns with the historical development of the electrical industry here, making it an essential component of American electrical systems.