Patent ID: 8576520

Claim:
A method for detecting arcs in a direct-current path of a photovoltaic system, comprising the following steps: detecting values of a current (I DC ) of the direct-current path during a repeating time frame; generating a mean value of the current (I DC ); detecting values of a voltage (U DC ) of the direct-current path during the time frame (t); generating a mean value of the voltage (U DC ); and continuously calculating at least one detection signal and at least one detection threshold based on the mean value of the current and mean value of the voltage by means of a calculation method, wherein the detection signal and the detection threshold are calculated by means of calculating a difference mean value, a long-term mean value and a long-term difference mean value of each of the current and the voltage by digital low-pass filtering, and wherein a value is generated from the long-term difference mean value and the difference mean value of the voltage, and multiplied by a value generated from the long-term difference mean value and the difference mean value of the current to generate the detection signal.