DPD02DM44 is a multifunction 3-phase mains monitoring relay designed to protect electrical systems by continuously monitoring voltage, frequency, and phase integrity. It operates on 3-phase (3P) and 3-phase plus neutral (3P+N) systems with a wide voltage range of 208 to 480 VAC and frequency range of 50 to 400 Hz, featuring ultra-high harmonic immunity for noisy environments. The device monitors phase loss, phase sequence, overvoltage, undervoltage, over/under frequency, and voltage asymmetry, with configurable alarm thresholds and two SPDT relay outputs for load control. Communication is enabled through NFC technology, allowing configuration and real-time monitoring via smartphone, tablet, or PC using the DPD APP without requiring device power during setup. DPD02DM44 is particularly suited for generators, renewable energy systems, combined heat and power installations, and sensitive loads requiring protection against voltage and frequency fluctuations.