Abstract: A method for monitoring the operating state of high-voltage devices of an energy supply network includes using sensors on or in the high-voltage devices to capture measured values. The measured values or values derived therefrom are transmitted to communication units via short-range communication connection. Access data are transmitted to a data processing cloud at a query time. The data processing cloud selects communication units dependent on the access data and connects to selected communication units via long-range communication connection. The measured values and/or values derived therefrom are transmitted from the selected communication units to the data processing cloud via the long-range connection. The data processing cloud uses the measured values and/or values derived therefrom for generating a visualization displaying the operating state of the high-voltage devices connected to at least one of the selected communication units via the short-range connection.