Electric service safety disconnect apparatus with overvoltage and overcurrent protection

• US 5,572,396 A
• Filed: 04/21/1995
• Issued: 11/05/1996
• Est. Priority Date: 04/21/1995
• Status: Expired due to Fees

• Current Assignee: Ekstrom Industries Incorporated
• Original Assignee: Ekstrom Industries Incorporated
• Inventors: Robinson, Darrell
• Primary Examiner(s): Gaffin, Jeffrey A.
• Assistant Examiner(s): SHERRY, MICHAEL JUDE
• Application Number:
  US08/425,887
• Time in Patent Office: 564 Days
• Field of Search: 361/93-95, 361/102-105, 361/111-112, 361/117-118, 361/56, 361/91, 361/126-127, 361/641, 361/643, 361/659-661, 361/668
• US Class Current: 361/117
• CPC Class Codes: G01R 1/36 Overload-protection arrangements or circuits for electric measuring instruments
• CPC Class Codes: G01R 11/04 Housings; Supporting racks; Arrangements of terminals
• CPC Class Codes: H02H 9/04 responsive to excess voltage lightning arrestors H01C7/12, H01C8/04, H01G9/18, H01T

Abstract

A socket adapter housing has a plurality of line and load blade terminals and jaw contacts. An electrical power disconnect device, mounted in the housing, has contacts switchable between closed and open states, the contacts being serially connected between the line blade terminals and the line jaw contacts. Rigid bus bars are fixedly connected to terminals on the power disconnect device extending from the switchable contacts and to the line blade and line jaws to fixedly mount the power disconnect device in the socket adapter housing. Surge suppression devices are connected between the load blade terminals and ground potential. An insulating safety shield is mounted in the housing and completely surrounds the line and load jaw contacts. Alternately, the housing includes a watthour meter receiving portion containing the power disconnect means and the line and load blade terminals and jaw contacts. An auxiliary housing is affixed along with the watthour meter receiving housing to a common base and contains the surge suppression devices. A cover is removably mountable on the auxiliary housing.

Claims

1. An electrical service protection and disconnect apparatus mountable in a watthour meter socket having a plurality of jaw contacts connected to electrical line conductors and electrical load conductors and normally receiving a watthour meter, the apparatus comprising:

a housing;

a plurality of line and load jaw contacts mounted in the housing for receiving line and load blade terminals of a watthour meter;

a plurality of line and load blade terminals mounted in the housing and extending outward from the housing for insertion into jaw contacts of a watthour meter socket;

electrical power disconnect means, mounted in the housing and connected between the line blade terminals and the line jaw contacts, for selectively controlling the application of power to the line jaw contacts in the housing; and

surge suppression means, mounted in the housing and electrically connected between ground potential and each load blade terminal, for conducting electrical surges to ground.

2. The apparatus of claim 1 wherein the housing comprises:

a base having a central wall and a peripheral edge; and

a shell having a bottom wall fixedly mounted on the peripheral edge of the base and an annular side wall extending axially from the base.

3. The apparatus of claim 2 wherein:

the line blade terminals are mounted in the central wall of the base; and

the line jaw contacts are mounted in the bottom wall of the shell.

4. The apparatus of claim 3 wherein the electrical power disconnect means comprises:

a first switchable contact connected between first and second terminals; and

a second switchable contact connected between first and second terminals.

5. The apparatus of claim 4 further comprising:

means for electrically connecting the first terminals of the first and second switchable contacts of the power disconnect means to the line blade terminals, and for connecting the second terminals of the first and second switchable contacts of the power disconnect means to the line jaw contacts.

6. The apparatus of claim 5 wherein the electrically connecting means comprises:

first and second electrical connectors, each electrically connected between one line blade terminal and a first terminal of the first and second switchable contacts; and

third and forth electrical connectors, each electrically connected between one line jaw contact and one second terminal of the first and second switchable contacts.

7. The apparatus of claim 6 wherein the first, second, third and forth electrical connectors comprise:

rigid, electrically conductive bus bars.

8. The apparatus of claim 7 wherein:

apertures are formed in the bottom wall of the shell; and

a portion of the first and second electrical connectors extend through the apertures and are electrically connected to the first terminals of the first and second switchable contacts and the line blade terminals.

9. The apparatus of claim 7 wherein:

the bus bars are fixedly connected to the first and second terminals of the power disconnect means to support the power disconnect means in the shell.

10. The apparatus of claim 1 wherein:

each load blade terminal and each load jaw contact are unitarily form as a one piece jaw blade having a jaw contact end and an opposed blade terminal end.

11. The apparatus of claim 2 wherein:

the central wall of the base is spaced from the bottom wall of the shell when the shell is fixedly connected to the base to form an interior chamber therebetween; and

the surge suppression means mounted in the interior chamber.

12. The apparatus of claim 11 wherein the surge suppression means comprises:

a plurality of metal oxide varistors; and

means for electrically connecting at least one metal oxide varistor to one of the load blade terminals.

13. The apparatus of claim 1 wherein the electrical power disconnect means comprises:

a circuit breaker switchable to an open, non-power conducting state at a predetermined current level.

14. The apparatus of claim 1 further comprising:

means for locking the electrical power disconnect means in a non-power conducting state, the locking means positioned exteriorly of the housing.

15. The apparatus of claim 14 wherein:

the electrical power disconnect means includes a plunger movable between at least two positions corresponding respectively to power conducting and non-power conducting states of the electrical power disconnect means;

the plunger having a length to slidably extend exteriorly through an aperture in the housing, with an end portion of the plunger disposed exteriorly of the housing when the power disconnect means is in the non-power conducting state; and

the locking means adapted to be coupled to the end portion of the plunger when the end portion of the plunger is disposed exteriorly of the housing.

16. The apparatus of claim 15 further comprising:

indicia disposed on the end portion of the plunger and visible exteriorly of the housing when the electrical power disconnect means is in the non-power conducting state to indicate that the electrical power disconnect means is in the non-power conducting state.

17. The apparatus of claim 16 wherein the locking means comprises:

an aperture formed in the end portion of the plunger, the aperture disposed externally of the housing when the electrical power disconnect means is in the non-power conducting state and adapted to receive the locking means therethrough.

18. The apparatus of claim 1 wherein the electrical power disconnect means comprises:

a ground fault circuit interrupter.

19. The apparatus of claim 1 wherein the housing comprises:

a watthour meter receiving housing portion;

the electrical power disconnect means mounted in the watthour meter receiving housing portion;

an auxiliary housing separate from the watthour meter receiving housing portion;

the surge suppression means mounted in the auxiliary housing;

electrical conductor means for electrically connecting the load jaw contacts in the watthour meter receiving housing portion to the surge suppression means in the auxiliary housing and to ground potential; and

a cover removably attachable to the auxiliary housing for closing access to the interior of the auxiliary housing.

20. The apparatus of claim 1 further comprising:

a base mounted on the housing, a plurality of line and load blade terminals mounted in the base and extending exteriorly of the base for insertion into jaw contacts in a watthour meter socket;

a watthour meter receiving first shell mounted on the housing for receiving a watthour meter, the electric power disconnect means and the line and load jaw contacts mounted in the first shell;

an auxiliary housing including a second shell mounted on the housing adjacent to the first shell, the surge suppression means mounted in the second shell; and

electrical conductor means for connecting the line blade terminals in the base to the electrical power disconnect means in the first shell, for connecting the electrical power disconnect means to the line jaw contacts in the first shell, for connecting the load jaw contacts in the first shell to the surge suppression means in the second shell, and for connecting the surge suppression means to the line blade terminals in the base and to ground potential.

21. The apparatus of claim 20 further comprising:

cover means, removably mounted on the second shell, for closing the interior of the second shell.

22. An electrical service protection and disconnect apparatus mountable in a watthour meter socket having a plurality of jaw contacts connected to electrical line conductors and electrical load conductors and normally receiving a watthour meter, the apparatus comprising:

a housing including a base having a central wall and a peripheral edge, and a shell having a bottom wall fixedly mounted on the peripheral edge of the base and an annular side wall extending axially from the base, the central wall of the base is spaced from the bottom wall of the shell when the shell is fixedly connected to the base to form an interior chamber therebetween;

a plurality of line and load jaw contacts mounted in the shell for receiving line and load blade terminals of a watthour meter;

a plurality of line and load blade terminals mounted in the base and extending outward from the base for insertion into jaw contacts of a watthour meter socket;

the load blade terminals electrically connected to the load jaw contacts;

electrical power disconnect means, mounted in the shell and serially connected between the line blade terminals and the line jaw contacts, for selectively controlling the application of power to the line jaw contacts in the shell; and

surge suppression means, mounted in the interior chamber and electrically connected between ground potential and each load blade terminal, for conducting electrical surges to ground.

23. An electrical service protection and disconnect apparatus mountable in a watthour meter socket having a plurality of jaw contacts connected to electrical line conductors and electrical load conductors and normally receiving a watthour meter, the apparatus comprising:

a housing;

a plurality of line and load jaw contacts mounted in the housing for receiving line and load blade terminals of a watthour meter;

a plurality of line and load blade terminals mounted in the housing and extending outward from the housing for insertion into jaw contacts of a watthour meter socket;

electrical power disconnect means, mounted in the housing and connected between the line blade terminals and the line jaw contacts, for selectively controlling the application of power to the line jaw contacts in the housing, the electrical power disconnect means including;

a first switchable contact connected between first and second terminals;

a second switchable contact connected between first and second terminals; and

means for electrically connecting the first terminal of the first and second switchable contacts of the power disconnect means to each of the line blade terminals, for connecting the second terminal of the first and second switchable contacts of the power disconnect means to each of the line jaw contacts, the electrically connecting means fixedly mounting the power disconnect means in the housing.

24. The apparatus of claim 23 further comprising:

rigid, electrically conductive bus bars fixedly connected to and extending between the first and second terminals of the switchable contacts of the power disconnect means and the associated line and load blade terminals and line and load jaw contacts.