System and method for detecting a protective device has limited or interrupted current it carries

• US 8,130,001 B1
• Filed: 05/19/2008
• Issued: 03/06/2012
• Est. Priority Date: 12/09/2007
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Culler, David E, Dutta, Prabal, Hong, Wei, Thaker, Malay
• Primary Examiner(s): VALONE, THOMAS F
• Application Number:
  US12/154,096
• Time in Patent Office: 1,387 Days
• Field of Search: 324/537
• US Class Current: 324/537
• CPC Class Codes: H01H 75/02 Details
• CPC Class Codes: H01H 9/167 Circuits for remote indication

Abstract

A system and method monitors indicators including other-than-current indicators of protective devices such as cutouts and reclosers, to determine whether the protective devices are restricting, below their rated capacity, or interrupting, current they carry. The system and method dispatches a technician to such device.

Claims

1. A method comprising:

providing a plurality of sensors, at least one of the plurality of sensors capable of providing at least one indication of at least one other-than-current condition of a protective device as it goes from a first state in which it is able to conduct current substantially at its rated capacity to a second state in which it is not able to conduct current substantially at its rated capacity, that the protective device has gone from the first state to the second state, at least near in time when at least one other of the plurality of sensors does not provide at least one indication of at least one different other-than-current condition of the protective device that the protective device has gone from the first state to the second state because of an influence of a device external to the protective device that is expected to occur;

receiving the at least one indication from at least one of the plurality of sensors that sense changes to a protective device as it goes from a first state in which it is able to conduct current substantially at its rated capacity to a second state in which it is not able to conduct current substantially at its rated capacity;

identifying at least one other-than-current indication as indicating that the protective device has at least reduced carrying current below its rated capacity from the at least one other-than-current indication received;

reporting an indication of the at least one other-than-current indication to a central device; and

identifying whether the at least one other-than-current indication is followed by at least one indication that the at least one other-than-current indication is a false positive rather than a true indication of an other-than-current condition of the protective device;

wherein the protective device comprises a cutout or recloser, the cutout or recloser being configured for use in a power distribution system.

2. The method of claim 1, additionally comprising receiving at least one indication of current from at least one of the plurality of sensors;

and

verifying the at least one indication of current.

3. The method of claim 1, additionally comprising providing a human observable indicator of the at least one other-than-current condition in a vicinity of the protective device.

4. The method of claim 1, wherein at least one of the at least one other-than-current conditions comprises movement of a component of the protective device that occurs when the protective device at least limits current.

5. The method of claim 1, wherein at least one of the at least one other-than-current conditions comprises sound or vibration from a component of the protective device that is generated when the protective device at least limits current.

6. The method of claim 1, wherein at least two of the sensor readings comprise other-than-current indications.

7. The method of claim 1, wherein at least one of the plurality of sensors is capable of providing at least one indication of at least one other-than-current condition, the at least one other-than-current condition being selected from a group comprising noise, vibration, movement of the protective device, orientation of an electric field, and change in orientation of an electric field.

8. The method of claim 1, wherein at least one of the plurality of sensors is capable of providing at least one indication of at least one other-than-current condition, the at least one other-than-current condition being movement of the protective device.

12. The system of claim 8, wherein at least one of the at least one other-than-current conditions comprises movement of a component of the protective device that occurs when the protective device at least limits current.

9. A system comprising:

a plurality of sensors, comprising a plurality of other-than-current sensors capable of sensing and providing at an output at least one indication of at least one other-than-current condition of a protective device as it goes from a first state in which it is able to conduct current substantially at its rated capacity to a second state in which it is not able to conduct current substantially at its rated capacity, that the protective device has gone from the first state to the second state,

at least near in time when at least one other of the plurality of sensors does not provide at least one indication of at least one different other-than-current condition of the protective device that the protective device has gone from the first state to the second state because of an influence of a device external to the protective device that is expected to occur;

at least one sensor manager having an input coupled to at least one of the plurality of sensors for receiving the at least one indication from at least one of the plurality of sensors that sense changes to a protective device as it goes from a first state in which it is able to conduct current substantially at its rated capacity to a second state in which it is not able to conduct current substantially at its rated capacity, the at least one sensor manager for identifying at least one other-than current indication as indicating that the protective device has at least reduced carrying current below its rated capacity from the sensor readings received, and for signaling at an output in response to such identifying, and for identifying whether the at least one other-than-current indication is followed by at least one indication that the at least one other-than-current indication is a false positive rather than a true indication of an other-than-current condition of the protective device; and

a report manager reporting an indication of the at least one other-than-current indication to a central device;

wherein the protective device comprises a cutout or recloser, the cutout or recloser being configured for use in a power distribution system.

10. The system of claim 9, additionally comprising receiving at least one indication of current from at least one of the plurality of sensors;

and

verifying the at least one indication of current.

11. The system of claim 9, additionally comprising providing a human observable indicator of the other-than-current condition in a vicinity of the protective device.

13. The system of claim 9, wherein at least one of the at least one other-than-current conditions comprises sound or vibration from a component of the protective device that is generated when the protective device at least limits current.

14. The system of claim 9, wherein at least two of the sensor readings comprise other-than-current indications.

15. The system of claim 9, wherein at least one of the plurality of sensors is capable of providing at least one indication of at least one other-than-current condition, the at least one other-than-current condition being selected from a group comprising noise, vibration, movement of the protective device, orientation of an electric field, and change in orientation of an electric field.

16. The system of claim 9, wherein at least one of the plurality of sensors is capable of providing at least one indication of at least one other-than-current condition, the at least one other-than-current condition being movement of the protective device.

17. A computer program product comprising a computer useable medium having computer readable program code embodied therein, the computer program product comprising computer readable program code devices configured to cause a computer system to:

provide a plurality of sensors, at least one of the plurality of sensors capable of providing at least one indication of at least one other-than-current condition of a protective device as it goes from a first state in which it is able to conduct current substantially at its rated capacity to a second state in which it is not able to conduct current substantially at its rated capacity, that the protective device has gone from the first state to the second state, at least near in time when at least one other of the plurality of sensors does not provide at least one indication of at least one different other-than-current condition of the protective device that the protective device has gone from the first state to the second state because of an influence of a device external to the protective device that is expected to occur;

receive the at least one indication from at least one of the plurality of sensors that sense changes to a protective device as it goes from a first state in which it is able to conduct current substantially at its rated capacity to a second state in which it is not able to conduct current substantially at its rated capacity;

identify at least one other-than-current indication as indicating that the protective device has at least reduced carrying current below its rated capacity from the at least one other-than-current indication received; and

report an indication of the at least one other-than-current indication to a central device; and

identify whether the at least one other-than-current indication is followed by at least one indication that the at least one other-than-current indication is a false positive rather than a true indication of an other-than-current condition of the protective device;

wherein the protective device comprises a cutout or recloser, the cutout or recloser being configured for use in a power distribution system.

18. The computer program product of claim 17, additionally comprising computer readable program code devices configured to cause the computer system to receive at least one indication of current from at least one of the plurality of sensors and to verify the at least one indication of current.

19. The computer program product of claim 17, additionally comprising computer readable program code devices configured to cause the computer system to provide a human observable indicator of the other-than-current condition in a vicinity of the protective device.

20. The computer program product of claim 17, wherein at least one of the at least one other-than-current conditions comprises movement of a component of the protective device that occurs when the protective device at least limits current.

21. The computer program product of claim 17, wherein at least one of the at least one other-than-current conditions comprises sound or vibration from a component of the protective device that is generated when the protective device at least limits current.

22. The computer program product of claim 17, wherein at least two of the sensor readings comprise other-than-current indications.

23. The computer program product of claim 17, wherein at least one of the plurality of sensors is capable of providing at least one indication of at least one other-than-current condition, the at least one other-than-current condition being selected from a group comprising noise, vibration, movement of the protective device, orientation of an electric field, and change in orientation of an electric field.

24. The computer program product of claim 17, wherein at least one of the plurality of sensors is capable of providing at least one indication of at least one other-than-current condition, the at least one other-than-current condition being movement of the protective device.