... protection JVRDphase sequence voltage protection device(Voltage and Phase Relay)Features:1,Phase Loss protection2,Phase sequence protection3,Under ... 50/60Hz, rated voltage 460V below, industrial three-phase 220V, 380V, 440V, 460V and so the voltage levels of ... , phase, reverse phase (phase sequence), to voltage unbalance relay protection, products are widely used in air compressor, electric motors ...