Circuit interrupting device with reset lockout

• US 8,054,595 B2
• Filed: 11/10/2009
• Issued: 11/08/2011
• Est. Priority Date: 08/24/1998
• Status: Expired due to Fees

• Current Assignee: Leviton Manufacturing Company Incorporated
• Original Assignee: Leviton Manufacturing Company Incorporated
• Inventors: DiSalvo, Nicholas L., Ziegler, William R.
• Primary Examiner(s): Jackson; Stephen W
• Application Number:
  US12/591,139
• Publication Number:
  US 20100134932A1
• Time in Patent Office: 728 Days
• Field of Search: 361/42
• US Class Current: 361/42
• CPC Class Codes: H01H 2083/045 Auxiliary switch opening testing circuit in synchronism with the main circuit
• CPC Class Codes: H01H 2083/201 the other abnormal electrical condition being an arc fault
• CPC Class Codes: H01H 71/524 the contact arm being pivoted on handle and mechanism spring acting between cradle and contact arm
• CPC Class Codes: H01H 71/62 with means for preventing resetting while abnormal condition persists, e.g. loose handle arrangement
• CPC Class Codes: H01H 83/04 with testing means for indicating the ability of the switch or relay to function properly
• CPC Class Codes: H02H 1/0015 Using arc detectors
• CPC Class Codes: H02H 11/002 in case of inverted polarity or connection; with switching for obtaining correct connection
• CPC Class Codes: H02H 3/338 also responsive to wiring error, e.g. loss of neutral, break
• CPC Class Codes: H02H 5/083 responsive to the entry or leakage of a liquid into an electrical appliance moisture alarm G08B21/20

Abstract

Resettable circuit interrupting devices, such as GFCI devices, that include reverse wiring protection, and optionally an independent trip portions and/or a reset lockout portion are provided. The reverse wiring protection operates at both the line and load sides of the device so that in the event line side wiring to the device is improperly connected to the load side, fault protection for the device remains. The trip portion operates independently of a circuit interrupting portion used to break the electrical continuity in one or more conductive paths in the device. The reset lockout portion prevents the reestablishing of electrical continuity in open conductive paths if the circuit interrupting portion is non-operational, if an open neutral condition exists or if the device is reverse wired. Methods for ensuring a reset lockout state before shipment are provided.

Claims

1. A resettable circuit interrupting device comprising:

an input electrical hot-line connection terminal;

an input electrical neutral-line connection terminal;

an output electrical hot-line connection terminal;

an output electrical neutral-line connection terminal;

a resettable circuit interrupter providing at least one of;

(a) a first interruptible connection along a first electrically conductive path between said input and output hot-line connection terminals, and

(b) a second interruptible connection along a second electrically conductive path between said input and output neutral-line connection terminals;

said resettable circuit interrupter having;

(i) a first state in which at least one of said interruptible connections presents a closed electrical circuit condition along its electrically conductive path, (ii) a second state in which said at least one interruptible connection presents an open electrical circuit condition along its electrically conductive path, (iii) an electrically operable circuit which causes transition from said first state to said second state when triggered, and (iv) a manually operable mechanism for resetting from said second state to said first state only if predetermined conditions are satisfied;

a fault-sensing circuit configured and connected to monitor currents flowing along said first and second conductive paths and to automatically trigger said circuit interrupter from said first state to said second state if unequal currents are detected flowing along said first and second conductive paths; and

a control circuit connected to said resettable circuit interrupter and to said fault-sensing circuit, said control circuit being engaged by said manually operable mechanism and configured to prevent resetting of the interrupter from said second state to said first state unless said predetermined conditions are satisfied, said predetermined conditions including at least;

(a) the fault-sensing circuit remains operative, and (b) the electrically operable circuit remains operative.

2. A resettable circuit interrupting device as in claim 1, wherein said first and second interruptible connections are disposed within a semi-conductor switching device.

3. A resettable circuit interrupting device as in claim 1, wherein said at least one interruptible connection comprises electro-mechanically and/or manually operated switch contacts that can be moved together and apart.

4. A resettable circuit interrupting device as in claim 3, wherein said manually operable mechanism comprises a manually operated spring-loaded reset switch configured when pushed against spring-loading to establish said control circuit causing a forced instance of unequal current flows in said first and second conductive paths by pushing in a first direction against a latch finger which is engaged with a movable electrical contact, said latch finger being thereafter shifted to re-engage said movable contact in a second opposite direction and to move the contact towards a reset condition where said first and second interruptible connections are in closed electrical circuit conditions only if said forced instance of unequal current flows is sensed by the fault-sensing circuit.

5. A resettable circuit interrupting device as in claim 4, wherein said forced instance of unequal current flows sensed by the fault-sensing circuit also causes an operation by said electrically operated circuit to insure its continued working condition.

21. A resettable circuit interrupting device as in claim 3, wherein said at least one of first and second interruptible connections comprises a latch member that is movable between a first and a second position with respect to a respectively corresponding movable electrically conductive path, each of said first and second latch positions inhibiting any changes in said at least one of first and second interruptible connections between said first and second states.

6. A resettable circuit interrupting device comprising:

an input electrical hot-line connection terminal;

an input electrical neutral-line connection terminal;

an output electrical hot-line connection terminal;

an output electrical neutral-line connection terminal;

a resettable circuit interrupter providing at least one of;

(a) a first interruptible connection along a first electrically conductive path between said input and output hot-line connection terminals and

(b) a second interruptible connection along a second electrically conductive path between said input and output neutral-line connection terminals;

a fault-sensing circuit configured and connected (a) to detect an abnormal current condition of current flowing along said first and/or second conductive paths and (b) to change said at least one of the first and second interruptible connections from closed to open electrical circuit conditions if abnormal current condition is detected; and

a reset-lockout circuit connected to said resettable circuit interrupter and to said fault-sensing circuit, said reset-lockout circuit being configured to prevent resetting of said at least one of the first and second interruptible connections from open to closed electrical circuit conditions unless said fault-sensing circuit is successfully tested and found operable to detect said abnormal current condition during an attempted resetting operation.

7. A resettable circuit interrupting device as in claim 6, wherein said first and second interruptible connections are disposed within a semi-conductor switching device.

8. A resettable circuit interrupting device as in claim 6, wherein said first and second interruptible connections comprise electro-mechanically and/or manually operated switch contacts that can be moved together and apart.

9. A resettable circuit interrupting device as in claim 8, comprising a manually operated spring-loaded reset switch configured when pushed against spring-loading to establish a test circuit causing a forced instance of said abnormal current condition by pushing in a first direction against a latch finger which is engaged with a movable electrical contact, said latch finger being thereafter shifted to re-engage said movable contact in a second opposite direction and to move the contact towards a reset condition where said first and second interruptible connections are in closed electrical circuit conditions only if said forced instance of abnormal current condition is sensed by the fault-sensing circuit.

10. A resettable circuit interrupting device as in claim 6, wherein said fault-sensing circuit detects unequal currents flowing along said first and second conductive paths as said abnormal current condition.

11. A method for insuring continued safe operation of a resettable circuit interrupting device having an input electrical hot-line connection terminal, an input electrical neutral-line connection terminal, an output electrical hot-line connection terminal, an output electrical neutral-line connection terminal, a first interruptible connection along a first electrically conductive path between said input and output hot-line connection terminals and a second interruptible connection along a second electrically conductive path between said input and output neutral-line connection terminals, said circuit interrupting device having:

(i) a first state in which said interruptible connections present a closed electrical circuit condition along each of said first and second electrically conductive paths, (ii) a second state in which said interruptible connections present an open electrical circuit condition along each of said first and second electrically conductive paths, (iii) an electrically operable circuit which causes transition from said first state to said second state when triggered, and (iv) a manually operable mechanism for resetting from said second state to said first state, said method comprising;

monitoring currents flowing along said first and second conductive paths and automatically triggering said circuit interrupting device from said first state to said second state if unequal currents are detected flowing along said first and second conductive paths; and

when said manually operable mechanism is used, preventing resetting from said second state to said first state unless said predetermined conditions are satisfied, said predetermined conditions including at least;

(a) the fault-sensing circuit remains operative, and (b) the electrically operable circuit remains operative.

12. A method as in claim 11, wherein said preventing step further comprises:

moving a latch from a first position to a second position, where the second position blocks said interruptible connection moving from said second state to said first state.

13. A method as in claim 11, wherein said first and second interruptible connections comprise electro-mechanically and/or manually operated switch contacts that can be moved together and apart.

14. A method as in claim 13, further comprising:

actuating said manually operable mechanism;

triggering a test circuit causing a forced instance of unequal current flows in said first and second conductive paths by pushing in a first direction against a latch finger which is engaged with a movable electrical contact;

moving said latch finger to re-engage said movable contact in a second opposite direction and to move the contact towards a reset condition where said first and second interruptible connections are in closed electrical circuit conditions only if said forced instance of unequal current flows is sensed by the fault-sensing circuit.

15. A method as in claim 14, wherein said forced instance of unequal current flows sensed by the fault-sensing circuit also causes an operation by said electrically operated circuit to insure its continued working condition.

16. A method for insuring continued safe operation of a resettable circuit interrupting device having an input electrical hot-line connection terminal, an input electrical neutral-line connection terminal, an output electrical hot-line connection terminal, an output electrical neutral-line connection terminal, a first interruptible connection along a first electrically conductive path between said input and output hot-line connection terminals and a second interruptible connection along a second electrically conductive path between said input and output neutral-line connection terminals, said method comprising:

detecting an abnormal current condition of current flowing along said first and/or second conductive paths and automatically changing said first and second interruptible connections from closed to open electrical circuit conditions if abnormal current condition is detected; and

preventing resetting of said first and second interruptible connections from open to closed electrical circuit conditions unless said resettable circuit interrupting device is successfully tested and found operable.

17. A method as in claim 16, wherein said first and second interruptible connections are disposed within a semi-conductor switching device.

18. A method as in claim 16, wherein said first and second interruptible connections comprise electro-mechanically and/or manually operated switch contacts that can be moved together and apart.

19. A method as in claim 18, further comprising:

actuating a manually operated spring-loaded reset switch to push against spring-loading to establish a test circuit causing a forced instance of said abnormal current condition by pushing in a first direction against a latch finger which is engaged with a movable electrical contact, said latch finger being thereafter shifted by operation of the fault-sensing circuit to re-engage said movable contact in a second opposite direction thereby causing the spring-loading to move the contact towards a reset condition where said first and second interruptible connections are in closed electrical circuit conditions only if said forced instance of abnormal current condition is sensed by the fault-sensing circuit.

20. A method as in claim 16, wherein said fault-sensing circuit detects unequal currents flowing along said first and second conductive paths as said abnormal current condition.

22. A resettable circuit interrupting device comprising:

a pair of fixed contact strips, each of the fixed contact strips having a fixed contact;

a pair of movable contact strips, each of the movable contact strips having a fixed end and a movable end, each of the movable ends having a movable contact arranged for contacting one of the fixed contacts;

a reset component comprising a reset button configured to engage a movable assembly including a latch capable of inhibiting at least one of the movable contact strips from moving from a first state to a second state and from a second state to a first state; and

a trip component configured to release the at least one movable contact strip from one of said first and second states upon detecting a predetermined condition.

23. A reseftable circuit interrupting device as in claim 22, further comprising:

a manually actuated trip mechanism disposed at least partially within a housing of said device and configured to break continuity between first and second conductive paths comprising respectively corresponding fixed and movable contact strips independently of said trip component.