Notes on the Measurement of Reactive Volt-Amperes

In the following paper, the character of the quantity known as reactive volt-amperes is first discussed and its dependence on the assumption of a definite type of periodicity is brought out, this in contrast to certain other a-c quantities. It is pointed out that on account of the rather complicated relation that it bears to the flow of energy in an electric circuit serious difficulties are met in its measurement except in the simpler conditions of balanced voltages, in a polyphase circuit, and sinusoidal waves. Two procedures are outlined which though they are not premised on balanced voltages have frequency and wave form limitations. In the latter part of the paper, the relation of the quantity of energy that surges in an a-c circuit in which there is energy storage, to the average flow of energy is considered, and advantages of this conception as a basis for rates are indicated. Finally, it is pointed out that reactive volt-amperes is of the nature of a complementary quantity rather than a specific activity of the electric circuit which when suitably combined with power gives volt-amperes.