Abstract: A method detects a high-impedance ground fault in an electrical energy supply network with a grounded neutral point. A test signal is fed via a detection device into the energy supply network, the test signal has a frequency which differs from the network frequency of the energy supply network. To enable a reliable detection, with low equipment costs, of high-impedance ground faults in energy supply networks with a grounded neutral point, a three-phase test signal is fed into the phase conductors of the energy supply network as the test signal. A measuring signal which indicates the residual voltage of the test signal is generated with the detection device. The residual voltage is compared with a threshold value using a test device of the detection device, and the presence of a high-impedance ground fault is detected if the residual voltage exceeds the threshold value.

Abstract: A method monitors an energy transmission device, in particular an energy transmission line or an energy distribution network, via which electric current is transmitted at a predefined network frequency. An electrical measurement signal having at least one non-network frequency, i.e. a frequency which differs from the network frequency, or a non-network frequency band, is fed into the energy transmission device at a predefined position thereon. An electrical measured quantity related to the non-network frequency or the non-network frequency band is measured at the predefined position or a different position on the energy transmission device with the formation of at least one measured value or frequency-band-related measured value characteristic.

Abstract: A method detects a high-impedance ground fault in an electrical energy supply network with a grounded neutral point. A test signal is fed via a detection device into the energy supply network, the test signal has a frequency which differs from the network frequency of the energy supply network. To enable a reliable detection, with low equipment costs, of high-impedance ground faults in energy supply networks with a grounded neutral point, a three-phase test signal is fed into the phase conductors of the energy supply network as the test signal. A measuring signal which indicates the residual voltage of the test signal is generated with the detection device. The residual voltage is compared with a threshold value using a test device of the detection device, and the presence of a high-impedance ground fault is detected if the residual voltage exceeds the threshold value.

Abstract: A method monitors an energy transmission device, in particular an energy transmission line or an energy distribution network, via which electric current is transmitted at a predefined network frequency. An electrical measurement signal having at least one non-network frequency, i.e. a frequency which differs from the network frequency, or a non-network frequency band, is fed into the energy transmission device at a predefined position thereon. An electrical measured quantity related to the non-network frequency or the non-network frequency band is measured at the predefined position or a different position on the energy transmission device with the formation of at least one measured value or frequency-band-related measured value characteristic.

Abstract: In order to simplify and design the configuration in particular of a power automation installation with a comparatively high number of power automation devices in such a way that as far as possible no interruption of operation is necessary, a method for operating a power automation installation is proposed, wherein the power automation installation includes a plurality of power automation devices and at least one higher-level installation control device for controlling and/or monitoring the power automation devices. An additional power automation device is connected to the concentrator device and automatic configuration of the concentrator device is carried out by the incorporation of a device description file of the additional power automation device into a concentrator data model of the concentrator device. There is also provided a corresponding power automation installation.