Fully Insulated Fuse Test and Ground Device

• US 20090108847A1
• Filed: 10/31/2007
• Published: 04/30/2009
• Est. Priority Date: 10/31/2007
• Status: Active Grant

• Current Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Original Assignee: Cooper Technologies Company (Eaton Corporation PLC.)
• Inventors: Whitmore, Steven Guy, Hughes, David Charles
• Granted Patent: US 7,695,291 B2
• Time in Patent Office: Days
• US Class Current: 324/511
• CPC Class Codes: G01R 31/74 Testing of fuses
• CPC Class Codes: H01H 85/30 Means for indicating condition of fuse structurally associated with the fuse
• CPC Class Codes: Y10S 439/921 Transformer bushing type or high voltage underground connector
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

A fuse test and ground device includes an insulated housing with a bore that extends from the front of the housing towards the rear of the housing. An electrical contact is disposed partially within the bore. A current interrupter, such as a fuse, is electrically connected between the contact and a testing ground lead. An eye, having it'"'"'s surface insulated by the housing, can be attached to the housing and provide a connection point for manipulation of the device. A grounding bore extends from a second aperture into the housing and provides an electrical connection to the contact. A grounding plug can be connected to ground on one end and inserted into the grounding bore to create a permanent ground for the device. An annunciator is connected to the current interrupter such that the annunciator provides an indication when a current flows through the current interrupter.

Claims

1. A test and ground device for power distribution systems comprising:

an electrically insulated housing with a bore that extends from an aperture at a front of the housing towards a rear of the housing;

an electrical contact disposed at least partially within the bore;

a current interrupter electrically connected between the electrical contact and a testing ground lead; and

an eye connected to a portion of the housing and proximate to the rear of the housing, the eye comprising an outer surface, wherein the outer surface of the eye is covered by the housing.

2. The device of claim 1, further comprising a connection point positioned within the housing for a permanent ground connection, wherein the connection point comprises a grounding bore extending from a second aperture in the housing towards an interior of the housing and capable of receiving the permanent ground connection, wherein the grounding bore provides a point of electrical connection to the electrical contact.

3. The device of claim 2, wherein the permanent ground connection is a grounding plug comprising:

a conductive shaft comprising a first end and a second end, said first end capable of being positioned through the second aperture and within the grounding bore of the connection point;

an operating eye electrically coupled to the second end of the conductive shaft; and

a grounding cable having a first end and a second end, said first end of the grounding cable being electrically connected to the conductive shaft and said second end capable of being connected to an electrical ground.

4. The device of claim 3, wherein the first end of the grounding plug further comprises a threaded tip, wherein rotation of the operating eye generates a corresponding rotation of the conductive shaft for coupling the threaded tip to the connection point.

5. The device of claim 3, wherein the grounding plug further comprises a compression connection coupled to the grounding cable and electrically connected to the conductive shaft.

6. The device of claim 3, further comprising:

a probe coupled to the first end of the conductive shaft and extending along a longitudinal axis of the conductive shaft, wherein the probe comprises a recess extending circumferentially around a portion of the probe; and

a plurality of finger contacts disposed within the grounding bore and electrically connected to the contact, wherein at least a portion of the finger contacts are received in the recess of the probe when the conductive shaft and the probe of the grounding plug are inserted into the grounding bore.

7. The device of claim 6, further comprising:

a disc positioned about a portion of the conductive shaft and having a diameter larger that the conductive shaft; and

a recess extending circumferentially around a portion of an inner surface of the grounding bore, wherein the disc is received in the recess of the grounding bore and creates an interference fit with the inner surface when the conductive shaft and the probe of the grounding plug are inserted into the grounding bore.

8. The device of claim 3, wherein the grounding plug further comprises a toggle lever coupled to the operating eye and the conductive shaft, wherein the toggle lever is rotatably maneuverable between a locked and an unlocked position, wherein the operating eye and conductive shaft are capable of axial rotation when the toggle lever is in the unlocked position, and wherein the toggle lever generates an increased compression force between a mounting sleeve and the conductive shaft when the toggle lever is in the locked position.

9. The device of claim 1, further comprising an annunciator proximate to the current interrupter, wherein the annunciator provides an indication when a current flows through the current interrupter.

10. The device of claim 1, wherein the current interrupter is a current limiting fuse.

11. The device of claim 1, further comprising an electrically conductive connection disposed within the housing and coupled to the electrical contact, the current interrupter, and the eye.

12. A test and ground device for power distribution systems comprising:

an electrically insulated housing with a bore that extends from an aperture at a front of the housing towards a rear of the housing;

an electrical contact disposed at least partially within the bore;

a current interrupter electrically connected between the contact and a testing ground lead;

an electrically conductive connection disposed within the housing and coupled to the electrical contact and the current interrupter;

an eye connected to a portion of the housing and proximate to the rear of the housing, the eye comprising an outer surface, wherein the outer surface of the eye is covered by the housing; and

a grounding bore extending from a second aperture in the housing towards an interior of the housing and capable of receiving a permanent ground connection, wherein the grounding bore provides a point of electrical connection to the electrical contact.

13. The device of claim 12, wherein the grounding bore provides a point of electrical contact to the electrically conductive connection.

14. The device of claim 12, further comprising a plurality of finger contacts disposed within the grounding bore and electrically connected to the electrical contact.

15. The device of claim 12, further comprising an annunciator proximate to the current interrupter, wherein the annunciator provides an indication when a current flows through the current interrupter.

16. The device of claim 12, wherein the grounding bore is positioned beneath the eye and horizontally disposed within the housing.

17. A grounding plug for completing a ground connection to a grounding and testing device comprising:

a conductive shaft comprising a first end and a second end;

an operating eye coupled to the first end of the conductive shaft; and

a grounding cable having a first lead end and a second lead end, said first lead end of the grounding cable being electrically connected to the conductive shaft and said second lead end capable of being connected to an electrical ground.

18. The grounding plug of claim 17, wherein the first end of the conductive shaft further comprises a threaded tip, wherein rotation of the operating eye generates a corresponding rotation of the conductive shaft for coupling the threaded tip to the grounding and testing device.

19. The grounding plug of claim 17, further comprising a compression connector coupled to the grounding cable on one end and electrically connected to the conductive shaft on another end.

20. The grounding plug of claim 17, further comprising an access plate positioned about a portion of the conductive shaft, wherein the access plate prevents manipulation of the grounding and testing device by a hotstick by way of a connection to an eye of the device when the grounding plug is connected to the device.

21. The grounding plug of claim 17, further comprising:

a probe coupled to the first end of the conductive shaft and extending along a longitudinal axis of the conductive shaft, wherein the probe comprises a recess extending circumferentially around a portion of the probe; and

a disc positioned about a portion of the conductive shaft and having a diameter larger that the conductive shaft, wherein the disc is capable of being received in a bore of the device when the grounding plug is connected to the device.

22. The device of claim 17, wherein the grounding plug further comprises a toggle lever coupled to the operating eye and the conductive shaft, wherein the toggle lever is rotatably maneuverable between a locked and an unlocked position, wherein the operating eye and conductive shaft are capable of axial rotation when the toggle lever is in the unlocked position, and wherein the toggle lever generates an increased compression force between a mounting sleeve and the conductive shaft when the toggle lever is in the locked position.

23. A method of grounding and testing electrical equipment in a power distribution system comprising the steps of:

providing a fuse test and ground device, said device comprising;

an electrically insulated housing with a bore that extends from an aperture at a front of the housing towards a rear of the housing;

an electrical contact disposed at least partially within the bore;

a current interrupter electrically connected between the contact and a testing ground lead;

an electrically conductive connection disposed within the housing and coupled to the electrical contact and the current interrupter;

an eye connected to a portion of the housing and proximate to the rear of the housing, the eye comprising an outer surface, wherein the outer surface of the eye is covered by the housing;

a grounding bore extending from a second aperture in the housing towards an interior of the housing and capable of receiving a permanent ground connection, wherein the grounding bore provides a point of electrical connection to the electrical contact; and

an annunciator proximate to the current interrupter, wherein the annunciator provides an indication when a current flows through the current interrupter;

connecting the testing ground lead to ground;

mating the bore, the aperture, and the contact to a bushing;

determining if the annunciator indicates that current has flowed through the current interrupter; and

inserting a grounding plug into the grounding bore and connecting the plug to the point of electrical connection based on the annunciator indicating that a current is not flowing through the current interrupter.

24. The method of claim 23, wherein the grounding plug comprises:

a conductive shaft comprising a first end and a second end;

an operating eye coupled to the first end of the conductive shaft; and

a grounding cable having a first lead end and a second lead end;

said first lead end of the grounding cable being electrically connected to the conductive shaft and said second lead end capable of being connected to ground.

25. The method of claim 24, further comprising the step of connecting the grounding cable to ground before the grounding plug is inserted into the grounding bore.