February 8, 2017. The National Institute of Standards and Technology (NIST) is a standards laboratory that is part of the U.S. Department of Commerce. The NIST traceable calibration refers to a program that certifies that the equipment used by labs or manufacturing facilities is properly calibrated according to the industry standards in place.
Quick Answer. VAC is an electrical voltage in an alternating current circuit. The power system supplying homes and businesses in the United States uses AC 120 V, while in Europe the system uses AC 240 V. Continue Reading.
Volt-ampere (VA) is a measurement of power in a direct current ( DC ) electrical circuit. The VA specification is also used in alternating current ( AC ) circuits, but it is less precise in this application, because it represents apparent power , which often differs from true power . In a DC circuit, 1 VA is the equivalent of one watt (1 W). The power, P (in watts) in a DC circuit is equal to the product of the voltage V (in volt s) and the current I (in ampere s): P = VI. In an AC circuit, power and VA mean the same thing only when there is no reactance .