Patents by Inventor John J. Culligan

John J. Culligan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Method and apparatus for sensing a ground fault in a motor control system
    Patent number: 5386183
    Abstract: A motor control unit for protecting a motor against ground fault currents. The unit monitors the currents in each phase of the motor to provide values representative of each phase current. The unit also includes a contactor for opening and closing each phase, wherein the unit controls the contactor based upon the values representative of the phase currents. The contactor is opened when a ground fault situation exists at the motor.
    Type: Grant
    Filed: January 18, 1994
    Date of Patent: January 31, 1995
    Assignee: Siemens Energy & Automation, Inc.
    Inventors: James T. Cronvich, Samir F. Farag, Daniel J. De Cicco, John J. Culligan