Phase

Alternating current is carried by conductors and a ground to residential, commercial, or industrial consumers. The waveform of the phase power appears as a single continuous sine wave at the system frequency whose amplitude is the rated voltage of the power.

Of a periodic, varying phenomenon, e.g., an electrical signal or electromagnetic wave, any distinguishable instantaneous state of the phenomenon, referred to a fixed reference or another periodic varying phenomenon. Note 1: Phase, i.e., phase time (frequently abbreviated simply to "phase" in informal usage), can be specified or expressed by time of occurrence relative to a specified reference. Note 2: The phase of a periodic phenomenon can also be expressed or specified by angular measure, with one period usually encompassing 360&176; (2 radians). Note 3: Phase may be represented (a) in polar coordinates by Mθ, where M is the magnitude and θ is the phase angle, and (b) in Cartesian coordinates, i.e., an Argand diagram, as (a + jb), where a is a real component and b is an imaginary component such that tan θ = (b/a), where θ is the phase angle, and the magnitude, M, is (a² + b²)^½ 2. A distinguishable state of a phenomenon. 3. That period of time during which a specified function occurs in a sequential list of functions.