A contactor is disclosed. The contactor includes one or more phase units, a mechanical drive and an electronic control module. Each phase unit includes an independent insulating housing, and, inside the housing, a positive pole, a static conducting rod, a negative pole, a moving conducting rod and a counter-force elastic component. The electronic control module drives a transmission to move, the transmission drives the central shaft to rotate, the central shaft drives the engagement between the moving conducting rod and the static conducting rod, the central shaft passes through the insulating housings of the one or more phase units and drives each phase unit, so that the contactor can be formed by absolutely independent phase units and it is convenient to add a phase unit along the central shaft so as to add rated operational current.