Measurement of current flowing through a rail with the use of Ohm's method; determination of the impedance of a rail

The article describes a method of measuring current flowing through a rail. This method is based on voltage drop measurement. For this method to be used correctly, it is necessary to know the resistance or impedance of the rail. A laboratory measurement was carried out, in order to determine the resistance and impedance of the rail, and subsequently a rail substitution diagram was created based on laboratory measurement results. A practical measurement on a railway track was performed to verify this substitution diagram as well as the whole designed measurement methodology.