Undervoltage tripping device

An undervoltage tripping device for actuating an appliance protective switch when the line voltage of an AC power line drops below a nominal value, the tripping device comprising:

• a rectifier (67) connected to the AC power line for converting AC current to DC current;
• a DC electromagnet including a magnetic winding (3) energizeable by DC current from the rectifier and a core (10) which is at least partially surrounded by the magnetic winding;
• an armature (20) magnetically coupled with the core and movable between an attracted position and a dropped position, the armature being in the attracted position when the line voltage of the power line is at the nominal value, the armature being spring-loaded to move from the attracted position to the dropped position when the line voltage of the power line drops below the nominal value;
• and
• a tripping member (50) connectable to the appliance protective switch and movable between a latched position and a released position for, when connected to the appliance protective switch and in the released position, actuating the appliance protective switch, the tripping member being mechanically coupled with the armature and movable relative to the armature, the armature acting as a ratchet for the tripping member to maintain the tripping member in the latched position when the line voltage of the power line is at the nominal value, the tripping member being spring-loaded from the latched position to the released position to thereby actuate the appliance protective switch when the line voltage of the power line drops below the nominal value, the tripping member moving the armature from the dropped position back to the attracted position when the tripping member is moved from the released position back to the latched position.