With Differential Sensing In A Polyphase System Patents (Class 361/44)
  • Ground fault and neutral fault detection circuit
    Patent number: 4012668
    Abstract: A circuit is disclosed for detecting ground faults and neutral faults and for providing power interruption in response thereto. The circuit monitors the current flow in the line and neutral conductors and provides a signal to a power interruption circuit in the event that a ground fault or a neutral fault condition is detected. In addition, a signal having a certain frequency is generated and coupled on the neutral line to enhance the probability of detecting neutral faults.
    Type: Grant
    Filed: December 20, 1974
    Date of Patent: March 15, 1977
    Assignee: RCA Corporation
    Inventor: Harold Allen Wittlinger