Portable optical AC- and proposed DC-current sensor for high voltage applications

The design and testing of a passive optical current sensor utilizing the Faraday effect is described. The system, being of the ring core sensor type, is portable and capable of being mounted on existing cables and power lines without disconnection. System performance regarding linearity, temperature dependence and the influence of current conductor displacement relative to the ring core are reported. A proper passive temperature compensation is tested and a scheme for optical measurement of DC-current proposed.<
>