In this research paper briefly describes the design and construction of an optical voltage transducer measurement based on the effect electro - optical Pockels. The equipment is designed to operate in electric transmission lines 110 kV AC. It then describes the electrical tests performed on transformer to actual operating conditions. In the design and construction of the optical transformer used a photorefractive crystal Bi₄Ge₃O₂₀ (BGO), which was used because of its high sensitivity to changes in the electric field as a light source is used a laser diode with a wavelength of 670 nm. Presents the results of performance tests on potential levels appropriate to the optical laboratory. In the second part of this work was subjected to optical transformer operating voltage levels of 110 kV ac in this test the voltage was applied gradually until the operating voltage. Team performance was satisfactory.