| 摘要 |
A ground fault detector for an AC circuit is responsive to resistive ground fault current but not to capacitive ground fault current. Current in the AC circuit is sensed and a corresponding signal current is produced. The direction of the signal current is reversed in each alternate half AC cycle without reversing the signal current in each intervening half cycle, the unreversed and the reversed signal current is averaged, and the presence of averaged signal current above a predetermined value is sensed to indicate significant resistive ground fault current.
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