Paper present practical solutions based on the utilization of graphene and amorphous alloys for construction of DC current transformer. Proposed solution is competitive as for the metrological properties and overall dimensions, and is well suited for the measurements of large currents in the railway traction. Use of amorphous alloys as magnetic materials for low-hysteresis and high- permeability cores, and development of highly sensitive graphene-based Hall effect sensors, allow for substantial improvements in the open feedback loop DC current transformers construction. In order to verify the usefulness of the developed DC current transformer, its characteristic was investigated. High linearity of the sensor is confirmed by the R-square parameter exceeding 0.99. The repeatability of the measurements was in the range of 1%. The properties of these materials raise the prospect of changes in the construction of the DC current transformers and open up the perspective of a number of innovative projects in the railway industry, in the current measurements area.