Page "Format war" Paragraph 4

* War of Currents: In the late 1880s, George Westinghouse and Thomas Edison became adversaries due to Edison's promotion of direct current ( DC ) for electric power distribution over alternating current ( AC ) advocated by several European companies and Westinghouse Electric based out of Pittsburgh, PA.

Ultimately, the AC power system prevailed.

Three phase 60 Hz at 208 / 120 volts became the dominant system in North America while 380 / 220 volts at 50 Hz became the standard in Europe.

The UK adopted a number of voltages and frequencies, but 415 / 240 volts at 50 Hz became the standard.

Europe has subsequently harmonised on a nominal voltage of 400 / 230 volts even though the actual voltage in individual countries has not changed.