The NAI iPM is an advanced, compact, DSP based System Power Monitor providing a precise instrument grade digital analysis of input power lines. The iPM will monitor single phase, three phase 4-wire wye or three phase Delta power lines at various input voltage levels and frequencies. This monitor is equipped with an EIA RS485 compatible serial communications interface that permits additional control functions and readout of diagnostic data and features a background self-test that constantly monitors the health of unit hardware and software. This NAI power monitor is designed and qualified to the most stringent performance and environmental requirements.