Abstract: A magneto-optic current transformer for measuring a current intensity of an electric current in an electrical conductor includes two light-guide units, each with an input polarizer, an output polarizer and a light guide arranged between the input and the output polarizer. A light-supply device is included which is configured to supply light to the light-guide units on the input side, and an analysis device which is configured to measure a luminous intensity of light output by the light-guide unit at the output side for each light-guide unit and to ascertain the current intensity of the electric current through the electrical conductor from the measured luminous intensities. A polarization axis of the output polarizer of each light-guide unit is rotated through a polarization angle in relation to a polarization axis of the input polarizer of the light-guide unit and the polarization angles of the two light-guide units differ from one another.

Abstract: An apparatus and a method are described for modifying test measurement signals for protective devices for electric power networks. The apparatus has an input interface to receive a first test measurement signal from a test generator, wherein the first test measurement signal is matched to a first electrical input characteristic of a first protective device for a power network. The apparatus further has an electrical modification system coupled to the input interface to convert the first test measurement signal into a second test measurement signal, wherein the second test measurement signal is matched to a second electrical input characteristic of a second protective device for the power network. The apparatus additionally has an output interface to output the second test measurement signal to the second protective device.

Abstract: An apparatus and a method are described for modifying test measurement signals for protective devices for electric power networks. The apparatus has an input interface to receive a first test measurement signal from a test generator, wherein the first test measurement signal is matched to a first electrical input characteristic of a first protective device for a power network. The apparatus further has an electrical modification system coupled to the input interface to convert the first test measurement signal into a second test measurement signal, wherein the second test measurement signal is matched to a second electrical input characteristic of a second protective device for the power network. The apparatus additionally has an output interface to output the second test measurement signal to the second protective device.