The Multi-functional Electric Power Instrument is designed for electric power intelligent monitoring and energy measurement requirements, capable of measuring all commonly used electric power parameters in the power grid with high precision, such as three-phase voltage, current, active power, reactive power, apparent power, power factor, frequency, active energy, reactive energy, four-quadrant energy, 4-channel switch input, 4-channel relay output, 4-channel analog output, and features include RS485 communication, 2-channel energy pulse output, 2-31 harmonics, dual-rate energy measurement, and more.