Method and system for optically detecting an electric current by means of light signals having different wavelengths

摘要

The method and system serve to optically detecting an electric current with an extended measurement range. To that end, two light signals having different wavelengths pass through a Faraday element, the polarization of the two light signals being rotated in each case by at least 0.0014°/A as a function of the electric current. By taking account of both wavelength-dependent polarization rotations, at least one of which lies beyond an unambiguity range, the measurement range is extended distinctly beyond the unambiguity range of each of the two light signals.