Circuit interrupter including a shunt wire current sensor and a processor having a thermal overload predictive function

• US 20080088991A1
• Filed: 10/13/2006
• Published: 04/17/2008
• Est. Priority Date: 10/13/2006
• Status: Active Grant

• Current Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Original Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Inventors: Elms, Robert T.
• Granted Patent: US 7,675,721 B2
• Time in Patent Office: Days
• US Class Current: 361/42
• CPC Class Codes: H01H 2083/201 the other abnormal electrical condition being an arc fault
• CPC Class Codes: H01H 2083/206 with thermal shunt trip
• CPC Class Codes: H01H 71/162 with compensation for ambient temperature
• CPC Class Codes: H01H 83/20 operated by excess current as well as by some other abnormal electrical condition

Abstract

A miniature circuit breaker includes separable contacts, an operating mechanism structured to open and close the separable contacts, a microprocessor including a thermal overload predictive function, and a shunt wire in series with the separable contacts. The shunt wire is structured to measure current flowing through the separable contacts for the thermal overload predictive function and an arc fault protective function.

Claims

1. A circuit interrupter comprising:

separable contacts;

an operating mechanism structured to open and close said separable contacts;

a processor including a thermal overload predictive function; and

a shunt wire in series with said separable contacts and being structured to measure current flowing through said separable contacts for said thermal overload predictive function.

2. The circuit interrupter of claim 1 wherein said processor further includes an arc fault circuit interrupter function;

and wherein said shunt wire also measures said current flowing through said separable contacts for said arc fault circuit interrupter function.

3. The circuit interrupter of claim 1 wherein said processor further includes a non-linear ambient temperature compensation function applied to said thermal overload predictive function.

4. The circuit interrupter of claim 1 wherein said processor further includes a plurality of protective functions.

5. The circuit interrupter of claim 4 wherein said circuit interrupter is a miniature circuit breaker.

6. The circuit interrupter of claim 4 wherein said circuit interrupter is an arc fault circuit breaker.

7. The circuit interrupter of claim 4 wherein said circuit interrupter is a ground fault circuit breaker.

8. The circuit interrupter of claim 4 wherein said circuit interrupter is an arc fault/ground fault circuit breaker.

9. The circuit interrupter of claim 1 wherein said processor further includes a nonvolatile memory saving ambient calibration information for said shunt wire.

10. The circuit interrupter of claim 1 wherein said thermal overload predictive function includes a diode temperature sensor cooperating with said shunt wire, and a nonvolatile memory saving ambient calibration information for said diode temperature sensor.

11. The circuit interrupter of claim 10 wherein said diode temperature sensor is proximate said shunt wire.

12. A circuit interrupter comprising:

separable contacts;

an operating mechanism structured to open and close said separable contacts;

a processor including a thermal overload predictive function and an arc fault circuit interrupter function; and

a shunt wire in series with said separable contacts and being structured to measure current flowing through said separable contacts for both of said thermal overload predictive function and said arc fault circuit interrupter function.

13. The circuit interrupter of claim 12 wherein said processor further includes a non-linear ambient temperature compensation function applied to said thermal overload predictive function.

14. The circuit interrupter of claim 12 wherein said processor further includes a plurality of protective functions.

15. The circuit interrupter of claim 14 wherein said circuit interrupter is a miniature circuit breaker.

16. The circuit interrupter of claim 14 wherein said circuit interrupter is an arc fault circuit breaker.

17. The circuit interrupter of claim 14 wherein said circuit interrupter is a ground fault circuit breaker.

18. The circuit interrupter of claim 14 wherein said circuit interrupter is an arc fault/ground fault circuit breaker.

19. The circuit interrupter of claim 12 wherein said processor further includes a nonvolatile memory saving ambient calibration information for said shunt wire.

20. The circuit interrupter of claim 12 wherein said thermal overload predictive function includes a diode temperature sensor cooperating with said shunt wire, and a nonvolatile memory saving ambient calibration information for said diode temperature sensor.

21. The circuit interrupter of claim 20 wherein said diode temperature sensor is proximate said shunt wire.