Volt-ampere

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volt-ampere
Apparent power (${\displaystyle S}$) is the magnitude of the vector sum of real power vector (${\displaystyle P}$) and reactive power vector (${\displaystyle Q}$); ${\displaystyle \varphi }$ is the phase shift between voltage and current.
General information
Unit system	SI units
Unit of	Apparent power
Symbol	V⋅A
Conversions
1 V⋅A in ...	... is equal to ...
SI base units	1 kg⋅m2⋅s−3

The volt-ampere (SI symbol: VA,^[1] sometimes V⋅A or V A) is the unit of measurement for apparent power in an electrical circuit. It is the product of the root mean square voltage (in volts) and the root mean square current (in amperes).^[2] Volt-amperes are usually used for analyzing alternating current (AC) circuits. In direct current (DC) circuits, this product is equal to the real power, measured in watts.^[3] The volt-ampere is dimensionally equivalent to the watt: in SI units, 1 V⋅A = 1 W. VA rating is most used for generators and transformers, and other power handling equipment, where loads may be reactive (inductive or capacitive).