| 摘要 |
An arc fault detection circuit collects samples of sensed current, determines a peak current value from the samples for each line cycle, determines a hysteresis value for a compressor load as a function of differences between the peak current values, and generates a trip signal responsive to the sensed current and the hysteresis value. The circuit determines a difference value for each line cycle from the present peak current value less the previous peak current value, low pas s filters the difference value to provide a low pass filtered value, determines a peak val ue from the low pass filtered value, determines that the absolute value of the low pass filtered value is less than a portion of the peak value and responsively saves the pe ak value, and determines the hysteresis value as a function of the saved peak value. A n operating mechanism opens separable contacts responsive to the trip signal.< /SDOAB>
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