Atmel’s AT73C500 + AT73C501-based meter chipset measures power and energy in three-phase systems or, alternatively,the chipset can be set to operate in a mode where it measures three separate, single-phase connections. In normal modes of operation, the chipset measures Y-connected threephase, four-wire environments, but there is no dedicated operating mode for Delta-connected three-phase, three-wire systems. This application note describes how to implement the chipset in threephase,three-wire environments.