Afci power circuit

A power circuit of an AFCI(Arc Fault Circuit Interrupter) is provided to prevent an erroneous operation due to various arc signals such as a lightening surge by obtaining circuit driving power through a CT(Current Transformer) for arc detection. In a power circuit of an AFCI, a conductive line to which AC power is supplied is wound around one side of a CT(21) by the pre-determined number of times. A rectifying unit(22) rectifies an AC voltage signal induced from the conductive line wound around the one side of the CT(21) into a DC signal. A constant voltage circuit(23) stabilizes the signal rectified by the rectifying unit(22) and supplies driving power needed for a circuit which determines whether an arc is generated.