①When the contactor coil is powered on, the coil current generates a magnetic field.

②The magnetic film is magnetized to generate electromagnetic suction, and then attracts the moving iron core to drives the tactical film, which result in the main contact closed (normally opern contact).

③When the coil is cut power off  , the electromagnetic suction power disappears;

④The iron core bounces off under the action of the reaction spring, and the tactile tactile reset, so that the main contact (normally open contact) disconnect.