Method for determining a load current (Iload) flowing through a group of measuring resistors, - wherein the group of measuring resistors has a number of branches and each branch has at least one respective first measuring resistor and one respective second measuring resistor, - wherein the method has the following steps for each of the branches: - measuring a first measurement voltage, which is dropped across the first measuring resistor, and a second measurement voltage, which is dropped across the second measuring resistor, - calculating a first operating parameter (a) on the basis of the first measurement voltage and the second measurement voltage, - calculating the load current (Iload) on the basis of at least the second measurement voltage and a second operating parameter (R*g), - wherein the method has the following steps solely during respective calibration periods: - conducting a calibration current (Iref) into the branch of the group of measuring resistors, wherein the calibration current (Iref) is divided into a first calibration partial current (Iref,1) flowing through the first measuring resistor and a second calibration partial current (Iref,2) flowing through the second measuring resistor, and - measuring a first calibration voltage, which is dropped across the first measuring resistor in the case of a flowing calibration current (Iref) and load current (Iload), and a second calibration voltage, which is dropped across the second measuring resistor in the case of a flowing calibration current (Iref) and load current (Iload), - wherein the second operating parameter (R*g) is calculated on the basis of at least the first calibration voltage, the second calibration voltage, the first operating parameter (a) and a current intensity of the calibration current (Iref). - wherein the group of measuring resistors has a number of branches and each branch has at least one respective first measuring resistor and one respective second measuring resistor, - wherein the method has the following steps for each of the branches: - measuring a first measurement voltage, which is dropped across the first measuring resistor, and a second measurement voltage, which is dropped across the second measuring resistor, - calculating a first operating parameter (a) on the basis of the first measurement voltage and the second measurement voltage, - calculating the load current (Iload) on the basis of at least the second measurement voltage and a second operating parameter (R*g), - measuring a first measurement voltage, which is dropped across the first measuring resistor, and a second measurement voltage, which is dropped across the second measuring resistor, - calculating a first operating parameter (a) on the basis of the first measurement voltage and the second measurement voltage, - calculating the load current (Iload) on the basis of at least the second measurement voltage and a second operating parameter (R*g), - wherein the method has the following steps solely during respective calibration periods: - conducting a calibration current (Iref) into the branch of the group of measuring resistors, wherein the calibration current (Iref) is divided into a first calibration partial current (Iref,1) flowing through the first measuring resistor and a second calibration partial current (Iref,2) flowing through the second measuring resistor, and - measuring a first calibration voltage, which is dropped across the first measuring resistor in the case of a flowing calibration current (Iref) and load current (Iload), and a second calibration voltage, which is dropped across the second measuring resistor in the case of a flowing calibration current (Iref) and load current (Iload), - wherein the second operating parameter (R*g) is calculated on the basis of at least the first calibration voltage, the second calibration voltage, the first operating parameter (a) and a current intensity of the calibration current (Iref). - conducting a calibration current (Iref) into the branch of the group of measuring resistors, wherein the calibration current (Iref) is divided into a first calibration partial current (Iref,1) flowing through the first measuring resistor and a second calibration partial current (Iref,2) flowing through the second measuring resistor, and - measuring a first calibration voltage, which is dropped across the first measuring resistor in the case of a flowing calibration current (Iref) and load current (Iload), and a second calibration voltage, which is dropped across the second measuring resistor in the case of a flowing calibration current (Iref) and load current (Iload), - wherein the second operating parameter (R*g) is calculated on the basis of at least the first calibration voltage, the second calibration voltage, the first operating parameter (a) and a current intensity of the calibration current (Iref).