A polyphase thermal kilovolt-ampere demand meter

The increasing need for a low-maintenance and relatively low-cost kilovolt-ampere demand meter has led to the design of a new type of thermal meter to accomplish this purpose. The complete unit includes a 2-element watt-hour meter as well as a thermal kilovolt-ampere demand meter in the same size base as a standard 3-element watt-hour meter, see Figure 1. Circuits for which the meter is available include: 3-phase, 3-wire; 3-wire network; 3-phase, 4-wire Y; and 3-phase, 4-wire delta.