Patent ID: 6281672
Filing Date: 2001-08-28
Classification: G01R

Abstract:
An optical current transformer, comprising:a light source for generating a polarized measuring light;an optical fiber wound n times around a conductor through which an electric current to be measured flows and arranged to circulate the polarized measuring light emitted from said light source around the conductor, a polarization plane of the polarized measuring light being rotated by a magnetic field generated by the electric current; andmeans for measuring the electric current by detecting an angle of rotation of the polarization plane of the polarized measuring light which transmits through said optical fiber, whereinsaid optical fiber has an incidental end connected to said light source and an emission end connected to said detecting means, and the incidental end and the emission end are arranged in such a manner that an angle obtained by viewing the two ends from the conductor is not more than 1% of 2 .pi.n radian wherein n is an integer less than or equal to 4 and said incidental end and said emission end are disposed in one member made of a magnetic material.