Patent ID: 8513964

Claim:
A circuit interrupter device comprising: a hot conducting circuit and a neutral conducting circuit for connecting to a power source; a fault detection circuit, coupled to the hot conducting circuit and the neutral conducting circuit, being responsive to at least a fault in the hot conducting circuit and the neutral conducting circuit to generate a first fault detection signal; a signal driving circuit, coupled to the fault detection circuit, being responsive to the first fault detection signal to generate a drive signal; a disconnecting mechanism, coupled to the signal driving circuit, for disconnecting an electrical connection in the hot conducting circuit and the neutral conducting circuit when the drive signal exceeds a predetermined level; a self-test circuit, coupled to the fault detection circuit and the signal driving circuit, for generating a self-test signal according to a predetermined time period and when an alternating current of the power source passes zero points, generating an evaluation result based on the self-test signal and a feedback signal of a second fault detection signal corresponding to the self-test signal, and generating one or more error signals if the evaluation result indicates a circuit error; and a device-state indicator circuit, coupled to the self-test circuit, for generating one or more alarms based on the one or more error signals; wherein the self-test circuit comprises: a zero-point sampling circuit, coupled to the hot conducting circuit and the neutral conducting circuit, for providing a zero-point sampling signal when the alternating current of the power source passes the zero points; and a self-test signal processing circuit, coupled to the zero-point sampling circuit and the fault detection circuit, for generating the self-test signal according to the predetermined time period and in response to the zero-point sampling signal, generating the evaluation result in response to the self-test signal and the feedback signal of the second fault detection signal corresponding to the self-test signal, and generating the one or more error signals based on the evaluation result that indicates the circuit error.