摘要 |
An arc fault current interrupting (AFCI) circuit breaker includes a pair of electrical contacts for stopping the flow of electrical current in a protected portion of the distribution circuit. A low pass filter is configured to receive a signal indicative of a voltage across a resistance in the distribution circuit. The low pass filter amplifies the signal and provides the signal to an arc fault detection circuit. The low pass filter includes an input resistance and a feedback resistance. In one embodiment of the invention, the input resistance has a positive temperature coefficient. In another embodiment, the feedback resistance has a negative temperature coefficient. In yet another embodiment, the input resistance has a positive temperature coefficient and the feedback resistance has a negative temperature coefficient. In any of the embodiments, when temperature decreases, the gain provided by the temperature compensation circuit increases due to the temperature coefficients of the input and/or feedback resistors. As a result, the arc fault detection circuitry will maintain a constant sensitivity to arc faults throughout the entire operating temperature range of the AFCI circuit breaker.
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