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[′vōlt ′am‚pir]
The unit of apparent power in the International System; it is equal to the apparent power in a circuit when the product of the root-mean-square value of the voltage, expressed in volts, and the root-mean-square value of the current, expressed in amperes, equals 1. Abbreviated VA.



a unit of full power of an alternating current, designated by VA. The full power of an alternating current is defined as the product of the effective values of the current in a circuit (in amperes) and the voltage at its terminals (in volts). The effective values of the current and voltage are measured by AC ammeters and voltmeters . The concept of full power is distinct from the real power of an electric circuit, which is expressed in watts and equals UI cos φ where φ is the angle of displacement of the phases between voltage U and current I, and as distinct from the reactive power, equal to UI sin φ and expressed in vars.

References in periodicals archive ?
According to a senior Project Officer at ADB Pakistan, the project would add 1,881 mega volt-amperes (MVA) of transformer capacity, 791 kilometers (km) of new transmission lines and up-gradation of 399 km of the existing transmission lines, which would bring stability in the distribution network.
The units deliver 500 volt-amperes for up to 9 min.
5 volt-amperes per sq ft for lighting instead of the 3.
The power calculator function is a dynamically updating display of Watts, Volt-Amperes, Amps, and BTU/hr.