Method for determining a topology information item on a low-voltage electrical distribution system, wherein in the method (a) a group of at least two current-measuring devices (17a-17e, 16a-16h) arranged at different points in the low-voltage distribution system is selected, (b) in each case the current is measured by the current-measuring devices (17a-17e, 16a-16h) so as to form a current measurement value, wherein time-averaged current measurement values of the fundamental component of the current flowing through the respective current-measuring devices (17a-17e, 16a-16h) are formed as current measurement values, wherein a start time and a period for a measurement of the current are predetermined for the current-measuring devices (17a-17e, 16a-16h) by means of a start signal and wherein the active current, averaged for the predetermined period, of the fundamental component of the current flowing through the respective current-measuring device is specified by an at least first current measurement value and the reactive current, averaged for the same predetermined period, of the fundamental component of the current flowing through the respective current-measuring device is specified by an at least second current measurement value, (c) the current measurement values are added so as to form a current sum taking into consideration the current flow direction and (d) a topology information item is formed, which specifies that the current-measuring devices (17a-17e, 16a-16h) electrically isolate a load-free and source-free section of the low-voltage distribution system when the current sum, in terms of absolute value, falls below a predetermined threshold value. (a) a group of at least two current-measuring devices (17a-17e, 16a-16h) arranged at different points in the low-voltage distribution system is selected, (b) in each case the current is measured by the current-measuring devices (17a-17e, 16a-16h) so as to form a current measurement value, wherein time-averaged current measurement values of the fundamental component of the current flowing through the respective current-measuring devices (17a-17e, 16a-16h) are formed as current measurement values, wherein a start time and a period for a measurement of the current are predetermined for the current-measuring devices (17a-17e, 16a-16h) by means of a start signal and wherein the active current, averaged for the predetermined period, of the fundamental component of the current flowing through the respective current-measuring device is specified by an at least first current measurement value and the reactive current, averaged for the same predetermined period, of the fundamental component of the current flowing through the respective current-measuring device is specified by an at least second current measurement value, (c) the current measurement values are added so as to form a current sum taking into consideration the current flow direction and (d) a topology information item is formed, which specifies that the current-measuring devices (17a-17e, 16a-16h) electrically isolate a load-free and source-free section of the low-voltage distribution system when the current sum, in terms of absolute value, falls below a predetermined threshold value.