Alternating current voltage loss alarm device for direct current screen of transformer substation

The utility model relates to the technical field of transformer substations, in particular to a transformer substation direct current screen alternating current voltage loss alarm device which comprises a box body and an alternating current voltage loss alarm mechanism fixed inside the box body. The alternating-current voltage loss alarm mechanism comprises a wireless transmitter, an alarm communication host, a fixing frame, a point contact switch, a first electromagnet, a telescopic rod, a second electromagnet and a spring, and the wireless transmitter, the alarm communication host, the fixing frame and the second electromagnet are all fixed to the inner side wall of the box body; one end of the telescopic rod is fixed to the first electromagnet, the other end of the telescopic rod is fixed to the second electromagnet, the telescopic rod is sleeved with the spring, and the point contact switch is fixed to the fixing frame. According to the utility model, when AC voltage loss occurs in a DC screen of a transf