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Fault indicator having delayed trip circuit

  • US 4,795,982 A
  • Filed: 04/24/1987
  • Issued: 01/03/1989
  • Est. Priority Date: 04/24/1987
  • Status: Expired due to Term
First Claim
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1. A fault indicator for indicating the occurrence of a fault current in a monitored electrical conductor of an alternating current power distribution system, comprising:

  • status indicating means having a reset-indicating state and a fault-indicating state;

    trip circuit means for conditioning said status indicating means to said fault-indicating state in response to the occurrence of a fault current in the conductor;

    reset circuit means periodically operable for a predetermined reset period for conditioning said status indicating means to said reset-indicating state, and inoperable for a predetermined recovery period following each such reset period; and

    said trip circuit means rendering said reset circuit means initially operable upon occurrence of a fault, and conditioning said status indicating means to said fault-indicating state during said recovery period following a trip delay per greater than said predetermined reset period to preclude simultaneous operation of said trip and reset circuits.

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