Patent ID: 7106069

Claim:
An apparatus for detecting an arc signal in a conductive wire of a circuit connecting a source to a load and determining whether or not the detected arc signal is a harmful arc signal, the apparatus comprising: a first current detector for detecting an RF current flowing through the conductive wire; an arc determination unit; a first arc detector for amplifying a weak RF signal outputted from the first current detector and removing an unnecessary RF signal to detect the arc signal and output the detected arc signal to the arc determination unit; a second current detector for detecting variation of current flowing through the conductive wire and generating a signal in proportional to the variation of the current; a second arc detector for amplifying an output signal of the second current detector and detecting an arc signal through a high frequency band pass filter; and a controller for controlling the first arc detector according to an output signal of the second current detector, removing unnecessary signals and attenuating an input signal level to apply an attenuated signal level to the arc determination unit, and attenuating an output signal of the second arc detector.