AC/dc source and drainage carrent free transducer

The utility model relates to an AC/DC high voltage leakage current sensor. The utility model is composed of a large current sensing unit, a transient pulse interference suppressor TVS, an overvoltage protector and a sensor module which are all connected in parallel, wherein, the sensor module is composed of an integrated circuit MAX472 and a service voltage acquiring circuit. The utility model utilizes service voltage collecting resistors to obtain an AC voltage by utilizing potential energy of detected leakage current, the AC voltage is rectified and filtered so as to obtain a service voltage of active devices so that the active devices can be used for passive detection, and thus the utility model breaks the traditional detection mode that a current transformer is utilized to conduct detection.