×

Microcomputer-controlled circuit breaker system

  • US 5,166,887 A
  • Filed: 01/28/1991
  • Issued: 11/24/1992
  • Est. Priority Date: 03/31/1988
  • Status: Expired due to Term
First Claim
Patent Images

1. An improved circuit breaker system for interrupting an electric current flow through at least one conductor from a source of electric energy to a load comprising:

  • a sensor circuit which measures current flow in said at least one conductor and for generating a signal corresponding to the magnitude of said current flow;

    a circuit breaker having a microcomputer associated therewith, said microcomputer including means for receiving said signal and for calculating at least one quantity responsive to said signal, said microcomputer including means for comparing said at least one quantity with at least one predetermined limit value, said microcomputer comprising means for disconnecting said load from said source by tripping said circuit breaker if said at least one quantity differs from said at least one predetermined limit value by at least a predetermined difference;

    a power supply circuit, coupled to said at least one conductor, for providing a secondary electric current flow proportional to said current flow in said at least one conductor, said power supply circuit including means for generating an output voltage proportional to said secondary electric current flow;

    means for connecting said output voltage to at least part of said circuit breaker to provide operating power to said at least part of said circuit breaker;

    a resistance circuit electrically associated with said power supply circuit; and

    means, responsive to the magnitude of current flow in said at least one conductor, for coupling said output voltage to said resistance circuit for a predetermined time interval to protect said at least part of said circuit breaker from an overvoltage condition arising if said output voltage exceeds an acceptable level.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×