There are several types of 3 phase power generators. These can vary from a utility power station, to a prime source power generator to portable diesel (and other fuels) 3 phase generator, to 3 phase generators which run on 1 phase power (some models of phase converters). At a utility power station, an electrical generator converts mechanical power into a set of alternating electric currents (AC), one from each electromagnetic coil or winding of the power generator. The currents are sinusoidal functions of time, all at the same frequency but with different phases. In a 3 phase system the phases are spaced equally, giving a phase separation of 120°. The frequency is typically 50 Hz in Europe and 60 Hz in the US (see List of countries with mains power plugs, voltages and frequencies). See Frequency Converters for changing 50 Hz to 60 Hz or the reverse of 60 Hz to 50 Hz frequency.................................