Optically coupled current meter for HV power line - has current transformer which controls transmissivity of optical channel containing voltage dependent crystal

摘要

An optically coupled instrument for measuring currents in a high tension line has a transparent crystal (4). The crystal has a voltage-dependent transmittivitidy and there is a pair of electrodes (5, 6) attached to a current transformer (2) which apply a voltage proportional to the current in the transformer primary in the high tension line. The faces of the crystal are connected in an optical transmission line (7, 8) so that the transmittivity of the optical line varies as the current to be measured.