What is Utility frequency?
[[File:50Hz60Hz.svg|thumb|50 Hz electricity and 60 Hz electricity comparison]] '''Utility frequency''', '''line frequency''' or '''mains frequency''' is the [[frequency]] level of the [[alternating current|AC]] [[electricity]] used in transmission and distribution from [[electricity generation]] sources to customers. The world's two major utility frequencies are 50&nbsp;[[Hertz|Hz]] (most, but not all, of the [[Eastern hemisphere]]) and 60&nbsp;Hz (most, but not all, of the [[Western hemisphere]]). Many [[Railway electrification system|electric railways]] in [[Europe]] use a frequency of 16.7 Hz (one third of 50 Hz). Early electric railways sometimes used 25 Hz (half of 50 Hz). New electric railways usually use the standard mains frequency of 50 Hz. Some lines in the northeast United States still use 25 Hz. [[Category:Electricity]] {{sci-stub}}