Rogovski coils detect the magnetic field that is created when Alternating current flows through an electrical conductor. The Current sensor provides a signal corresponding to the current, which can then be processed by measuring instruments. The measuring sensors are particularly suitable for retrofitting systems because the coil can be cut open. This means that it can be attached to cables or busbars without prior dismantling. Further advantages for AC current measurement are the complete suppression of DC influences, very good linearity, low power consumption and high temperature independence. Furthermore, the sensors have very good protective properties, as the measuring signal is separated from the measuring current, which protects the measuring device to which the signal is supplied from the current conductor to be measured. The measuring signal is a µV or mV signal per ampere of the current to be measured. When mounting, care should be taken to ensure that the closure of the coil is not close to the current conductor, as this reduces the measuring accuracy. Due to the flexibility of the design, it is also possible to enclose several current-carrying lines at the same time in order to carry out a current measurement.