A charging system for charging a battery includes a rectifier that rectifies power received from an AC power source into a DC signal for charging the battery and an arc detection circuit that measures noise added to the DC signal and generates a measured noise signal. A processor analyzes the measured noise signal to detect a series-arc and, when a series-arc is detected, causes a shunt of the AC current of the rectifier for a period of time to reduce a DC output of the rectifier toward zero. A passive arc detection circuit is inserted between the rectifier and the battery and includes a filter capacitor and a sense resistor in parallel with a smoothing capacitor. A voltage across the sense resistor is amplified, digitized, and outputted as the measured noise signal. The DC signal may be scanned to obtain the measured noise signal in different frequency windows.