Claims
- 1. A method for dissipating energy in a circuit interrupter, the method comprising the steps of:
(a) providing first and second current carrying paths electrically coupled in parallel between two conductors, the first current carrying path including a movable contact structure and the second current carrying path including a controllable resistive element; (b) closing the movable contact structure to direct electrical current through the first current carrying path and substantially no current through the second current carrying path; (c) opening the movable contact structure; (d) transferring a portion of the current flow through the second current carrying path; and (e) transitioning a resistive state of the controllable resistive element from a first resistance to a second resistance higher than the first resistance.
- 2. The method of claim 1, wherein the first and second current carrying paths both conduct current at least during an initial phase of interruption.
- 3. The method of claim 2, wherein current through the first current carrying path is interrupted before current through the second current carrying path.
- 4. The method of claim 1, wherein step (b) includes urging a movable conductive element into contact with a stationary conductive element.
- 5. The method of claim 4, wherein step (c) includes displacing the movable conductive element under the influence of an interruption initiating device.
- 6. The method of claim 5, wherein the interruption initiating device includes an electromagnetic, assembly positioned adjacent to the movable conductive element for displacing the movable conductive element via an electromagnetic field.
- 7. The method of claim 1, wherein the current flow is transferred from the first current carrying path to the second current carrying path by providing a resistance to current flow through at least a portion of the second current carrying path less than a resistance to current flow through the first current carrying path.
- 8. The method of claim 1, wherein the second current carrying path includes the controllable resistive element electrically in series with a plurality of energy dissipating members.
- 9. The method of claim 6, wherein the energy dissipating members include a plurality of conductive plates spaced from one another by respective air gaps.
- 10. The method of claim 1, wherein the controllable resistive element includes a plurality of variable resistive members coupled to one another electrically in series.
- 11. A method for interrupting electrical current through a circuit interrupter, the method comprising the steps of:
(a) defining a first current carrying path through the interrupter; (b) defining a second current carrying path including a variable resistive element electrically in series with a plurality of energy dissipating members, the second current carrying path being electrically in parallel with the first current carrying path; (c) directing electrical current through the first current carrying path; (d) opening the first current carrying path; (e) directing electrical current through both the first and second current carrying paths during an initial phase of interruption; and (f) terminating electrical current through the first and second current carrying paths by combined resistances of the current carrying paths.
- 12. The method of claim 11, wherein resistance of the first current carrying path includes resistance of an arc between a movable contact and a stationary contact.
- 13. The method of claim 12, wherein resistance of the second current carrying path increases as current is directed through the second current carrying path.
- 14. The method of claim 11, including the further step of transitioning the variable resistive element from a first resistance to a second resistance higher than the first resistance.
- 15. The method of claim 11, wherein current through the first current carrying path is terminated before current through the second current carrying path.
- 16. The method of claim 11, wherein the second current carrying path includes a plurality of variable resistive elements electrically in series with one another.
- 17. The method of claim 11, wherein the variable resistive element is transitioned from the first resistance to the second resistance by heating.
- 18. A method for interrupting electrical current through an electrical device, the method comprising the steps of:
(a) directing substantially all of the electrical current through a first current carrying path within the device; (b) initiating interruption of the first current carrying path during an initial phase of interruption; (c) directing current through the first current carrying path and a second current carrying path in parallel with the first current carrying path during an intermediate phase of interruption, the second current carrying path including in series at least one variable resistance element, a plurality of conductive plates, and a plurality of air gaps; (d) terminating current flow through the first and second current carrying paths in a final phase of interruption.
- 19. The method of claim 18, wherein the variable resistance element is disposed between a conductor of the first current carrying path and a conductive plate of the second current carrying path, and wherein current is drawn toward the second current carrying path in the intermediate phase of interruption by a comparatively lower resistance of the variable resistance element and an arc established in the first current carrying path.
- 20. The method of claim 19, wherein step (d) includes the step of increasing resistance of the second current carrying path.
- 21. The method of claim 19, wherein step (a) includes providing sufficient resistance to flow of electrical current through the second current carrying path to completely inhibit current flow through the second current carrying path.
- 22. The method of claim 19, wherein interruption of the first current carrying path is initiated by displacing a conductive contact member from a stationary contact member within the first current carrying path.
- 23. The method of claim 19, wherein in step (d) current is terminated through the first current carrying path before current is terminated through the second current carrying path.
- 24. The method of claim 19, wherein the resistance of the second current carrying path is increased by increasing the resistance of a variable resistance element of the second current carrying path.
- 25. The method of claim 19, wherein the second current carrying path includes a plurality of variable resistance elements electrically coupled to one another in series, the variable resistance elements transitioning between resistive states as a function of temperature during the intermediate phase of interruption.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of application Ser. No.09/219,726 filed on Dec. 22, 1998.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09219726 |
Dec 1998 |
US |
Child |
09409126 |
Sep 1999 |
US |