A method for determining an adjustment value for an electrical protection device wherein, upon occurrence of a ground short circuit, first current indicator measured values and first voltage indicator measured values are captured by a first measurement device at a first end of a segment of an electrical power supply line, and second current indicator measured values and second voltage indicator measured values are captured by a second measurement device at a second end of the segment of an electrical power supply line. In order to design a method of this type such that an adjustment value for a ground impedance can be determined in a relatively simple fashion. A fault location value is determined using the first current and voltage indicator measured values and the second current and voltage indicator measured values, indicating a fault location at which the ground short circuit has occurred in the segment of the electrical power supply line, and an adjustment value indicating a ground impedance is calculated using the fault location value. There is also provided a correspondingly equipped measurement device.