| 摘要 |
An arc fault current interrupting (AFCI) circuit breaker (10) includes a pair of electrical contacts (20, 34) for stopping the flow of electrical current in a protected portion of the distribution circuit. A low pass filter (102) is configured to receive a signal indicative of a voltage across a resistance (106) in the distribution circuit. The low pass filter (102) amplifies the signal and provides the signal to an arc fault detection circuit. The low pass filter (102) includes an input resistance (106) and a feedback resistance (108). In one embodiment of the invention, the input resistance (106) has a positive temperature coefficient. In another embodiment, the feedback resistance (108) has a negative temperature coefficient. In yet another embodiment, the input resistance (106) has a positive temperature coefficient and the feedback resistance (108) has a negative temperature coefficient. In any of the embodiments, when temperature decreases, the gain provided by the temperature compensatio n circuit (100) increases due to the temperature coefficients of the input and/or feedback resistors ((106, 108). As a result, the arc fault detection circuitry will maintain a constant sensitivity to arc faults throughout the entire operating temperatu re range of the AFCI circuit breaker (10).
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