Method for measuring phase sequence through sampling three-phases AC in slicing time

A method for measuring phase sequence of three-phase AC by time - sharing sampling includes using a probe to pick up AC voltage signal on three phases separately and reforming obtained AC sine wave voltage to be square wave; using 2n pi point as rising edge or falling edge for A phase square wave, 2n pi' point for B phase square wave and 2n pi' point for C phase square wave; and comparing three phase square waves with virtual D. The device for realizing the method is also disclosed.