Current transformer

The utility model relates to a mutual inductor, in particular to a current transformer with double functions of power supply and sampling of a quick saturation mutual inductor and a hollow mutual inductor. The packaging box comprises a box body, an iron core shaped like a Chinese character'ri 'is arranged in the box body, a quick saturation mutual inductance coil is wound on an outer transverse frame of the iron core, a hollow mutual inductance coil is arranged on one side of the iron core, a coil hole of the hollow mutual inductance coil corresponds to the threading hole of the iron core awayfrom the quick saturation mutual inductance coil in position, and receding holes are formed in the box body corresponding to the threading hole and the coil hole of the hollow mutual inductance coil.The hollow mutual inductance coil is characterized in that the hollow mutual inductance coil comprises an annular framework and enameled wires, the annular framework is made of non-magnetic materials, and the enameled wires a