Electrical switching apparatus and receptacle including automatic miswiring protection

• US 7,518,840 B2
• Filed: 02/14/2006
• Issued: 04/14/2009
• Est. Priority Date: 02/14/2006
• Status: Active Grant

• Current Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Original Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Inventors: Elms, Robert T.
• Primary Examiner(s): Leja; Ronald W
• Application Number:
  US11/353,501
• Publication Number:
  US 20070188955A1
• Time in Patent Office: 1,155 Days
• Field of Search: 361/42
• US Class Current: 361/42
• CPC Class Codes: H02H 1/0015 Using arc detectors
• CPC Class Codes: H02H 3/338 also responsive to wiring error, e.g. loss of neutral, break

Abstract

A receptacle includes a line conductor, a load conductor, a neutral conductor, a load neutral conductor, a ground conductor, first separable contacts electrically connected between the line and load conductors, and second separable contacts electrically connected between the neutral and load neutral conductors. An operating mechanism is structured to open and close the first and second separable contacts. A number of voltages are input from at least some of the conductors. An electronic trip mechanism automatically detects: (a) an arc fault trip condition, and (b) a second different miswiring condition from the voltages and cooperates with the operating mechanism to trip open the separable contacts in response to the automatically detected miswiring condition.

Claims

1. An electrical switching apparatus comprising:

a line conductor;

a load conductor;

at least one neutral conductor;

separable contacts electrically connected between said line conductor and said load conductor;

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

a first input inputting a first voltage between said line conductor and said at least one neutral conductor;

a second input inputting a second voltage between said load conductor and said at least one neutral conductor; and

a trip mechanism structured to automatically detect a reverse feed condition from the first and second voltages of said first and second inputs, respectively, and to cooperate with said operating mechanism to trip open said separable contacts in response to said automatically detected reverse feed condition.

2. The electrical switching apparatus of claim 1 wherein said trip mechanism is an electronic trip mechanism structured to detect an arc fault condition and responsively initiate a trip signal to trip open said operating mechanism, said electronic trip mechanism being further structured to initiate said trip signal in response to said automatically detected reverse feed condition when said first voltage is less than a first predetermined value, and said second voltage is greater than a second predetermined value, which is greater than said first predetermined value.

3. The electrical switching apparatus of claim 1 wherein said trip mechanism is further structured to automatically detect said reverse feed condition and to cause a trip signal to trip open said operating mechanism when said first voltage is less than a first predetermined value, and said second voltage is greater than a second predetermined value, which is greater than said first predetermined value.

4. The electrical switching apparatus of claim 3 wherein said trip mechanism comprises an arc fault or ground fault protection circuit, a reset button structured to cooperate with said operating mechanism to close said separable contacts, and a test circuit structured to test said arc fault or ground fault protection circuit;

and wherein said trip mechanism is further structured to detect said reverse feed condition in response to said test circuit when said separable contacts are closed.

5. The electrical switching apparatus of claim 4 wherein said reset button and said operating mechanism are further structured to inhibit closing said separable contacts in response to said trip signal.

6. The electrical switching apparatus of claim 3 wherein said trip mechanism is further structured to remove said trip signal as a function of said first voltage and said second voltage when:

(a) both of said first voltage and said second voltage are less than said first predetermined value, or (b) said second voltage is less than said first predetermined value and said first voltage is greater than said second predetermined value.

7. The electrical switching apparatus of claim 6 wherein said trip mechanism is further structured to remove said trip signal after a predetermined time.

8. The electrical switching apparatus of claim 6 wherein said trip mechanism is further structured to remove said trip signal after a predetermined time and to cause said trip signal to trip open said operating mechanism when said first voltage is less than said first predetermined value, and said second voltage is greater than said second predetermined value, which is greater than said first predetermined value.

9. The electrical switching apparatus of claim 3 wherein said trip mechanism is powered from both of the first voltage from said line conductor and the second voltage from said load conductor.

10. An electrical switching apparatus comprising:

a line conductor;

a load conductor;

at least one neutral conductor;

a ground conductor;

separable contacts electrically connected between said line conductor and said load conductor;

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

an input inputting a voltage between said at least one neutral conductor and said ground conductor; and

an electronic trip mechanism structured to automatically detect;

(a) a first trip condition operatively associated with current flowing through said separable contacts, and (b) a second different swapped line and neutral condition from said voltage, said electronic trip mechanism cooperating with said operating mechanism to trip open said separable contacts in response to said first trip condition or said second different swapped line and neutral condition.

11. The electrical switching apparatus of claim 10 wherein said electronic trip mechanism is further structured to detect said second different swapped line and neutral condition and initiate a trip signal to trip open said operating mechanism when said voltage is greater than a predetermined value.

12. The electrical switching apparatus of claim 11 wherein said predetermined value is a second predetermined value;

and wherein said electronic trip mechanism is further structured to remove said trip signal when said voltage is less than a first predetermined value, which is less than said second predetermined value.

13. The electrical switching apparatus of claim 11 wherein said electronic trip mechanism is further structured to annunciate said second different swapped line and neutral condition.

14. The electrical switching apparatus of claim 10 wherein said electronic trip mechanism comprises a first indicator and a second indicator, said second indicator being off and said first indicator being flashing to indicate a normal condition, said first indicator being off and said second indicator being flashing to indicate said second different swapped line and neutral condition, and both of said first and second indicators being off to indicate an end of life condition of said electrical switching apparatus.

15. The electrical switching apparatus of claim 10 wherein said electronic trip mechanism is further structured to automatically detect a reverse feed condition;

and wherein said electronic trip mechanism comprises at least one of an arc fault protection circuit and a ground fault protection circuit structured to output a trip signal to said operating mechanism responsive to said first trip condition, a first indicator and a second indicator, said second indicator being off and said first indicator being flashing to indicate a normal condition, said first indicator being off and said second indicator being flashing with a first pattern to indicate said reverse feed condition, said first indicator being off and said second indicator being flashing with a second pattern to indicate said second different swapped line and neutral condition, said first indicator being off and said second indicator being on to indicate an arc fault or ground fault condition, and both of said first and second indicators being off to indicate an end of life condition of said electrical switching apparatus.

16. The electrical switching apparatus of claim 10 wherein said electronic trip mechanism comprises a processor;

wherein said first input comprises a first analog to digital converter channel cooperating with said processor to input said first voltage thereto; and

wherein said second input comprises a second analog to digital converter channel cooperating with said processor to input said second voltage thereto.

17. The electrical switching apparatus of claim 10 wherein said electrical switching apparatus is a receptacle;

wherein said separable contacts are a single set of separable contacts electrically connected between said line conductor and said load conductor; and

wherein said line conductor and said load conductor are directly electrically connected together by said single set of separable contacts.

18. The electrical switching apparatus of claim 10 wherein said electrical switching apparatus is a circuit breaker;

and wherein said electronic trip mechanism comprises a processor initiating a trip signal, and a trip solenoid receiving said trip signal and cooperating with said operating mechanism to trip open said operating mechanism in response to said trip signal.

23. The electrical switching apparatus of claim 10 wherein said electronic trip mechanism comprises a microcomputer including said input.

19. An electrical switching apparatus comprising:

a line conductor;

a load conductor;

a neutral conductor;

a load neutral conductor;

a ground conductor;

first separable contacts electrically connected between said line conductor and said load conductor;

second separable contacts electrically connected between said neutral conductor and said load neutral conductor;

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

at least one input inputting at least one voltage obtained from at least a plurality of said conductors; and

an electronic trip mechanism structured to automatically detect;

(a) a first trip condition operatively associated with said separable contacts, and (b) a second different miswiring condition from said at least one voltage, said electronic trip mechanism cooperating with said operating mechanism to automatically trip open said separable contacts in response to said first trip condition or said second different miswiring condition.

20. The electrical switching apparatus of claim 19 wherein said at least one voltage is a first voltage and a second voltage;

wherein said at least one input comprises a first input and a second input, said first input inputting the first voltage between said line conductor and said neutral conductor, said second input inputting the second voltage between said load conductor and said load neutral conductor;

wherein said miswiring condition is a reverse feed condition; and

wherein said electronic trip mechanism is further structured to detect said reverse feed condition and initiate a trip signal to trip open said operating mechanism when said first voltage is less than a first predetermined value, and said second voltage is greater than a second predetermined value, which is greater than said first predetermined value.

21. The electrical switching apparatus of claim 19 wherein said at least one voltage is a voltage;

wherein said at least one input is an input inputting the voltage between said neutral conductor and said ground conductor;

wherein said miswiring condition is a swapped line and neutral condition; and

wherein said electronic trip mechanism is further structured to detect said swapped line and neutral condition and initiate a trip signal to trip open said operating mechanism when said voltage is greater than a predetermined value.

22. The electrical switching apparatus of claim 19 wherein said first trip condition is an arc fault trip condition.

24. The electrical switching apparatus of claim 19 wherein said electronic trip mechanism comprises a microcomputer including said at least one input.