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Revision as of 22:37, 1 October 2003 by Reddi (talk | contribs)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)Three phase is a common method of electric power transmission in industrialised countries. It is a type of a polyphase system.
At the power station an electrical generator converts mechanical power into a set of alternating electric currents, one from each electromagnetic coil or winding of the generator. The currents are sinusoidal functions of time, all at the same frequency but with different phases. In a three-phase system the phases are spaced equally, separated from each other by 120°. The frequency is typically 50 Hz in Europe and 60 Hz in the US.
All three phases are typically used in large industrial motors as this is the most efficient way to transmit large amounts of electrical power. The greatest power demand is when starting the motor.
For further information on three phase circuits see:
See also: single phase electric power, alternating-current electric power, polyphase systems