The fundamental accuracy of single-phase 3-wire metering

As a result of constantly increasing loads, 3-wire single-phase service is rapidly replacing the original 2-wire domestic service. This change has been accompanied by continuous improvement in the range and performance of the meters. In view of these developments, it is appropriate to analyze the bases upon which the fundamental correctness of 3-wire single-phase metering rests and which have been responsible for its universal acceptance for many years. The analysis in this paper shows that this acceptance is well founded, that the probable error of this form of metering can be calculated readily, and that it is usually negligible.