Fuse block protector

• US 5,365,395 A
• Filed: 11/02/1992
• Issued: 11/15/1994
• Est. Priority Date: 11/02/1992
• Status: Expired due to Fees

• Current Assignee: Core Brands, LLC (Melrose Industries Plc)
• Original Assignee: Panamax LLC (Melrose Industries Plc)
• Inventors: Callaway, Jerry
• Primary Examiner(s): DEBOER, TODD
• Application Number:
  US07/970,017
• Time in Patent Office: 743 Days
• Field of Search: 361/56, 361/104, 361/111, 361/58, 439/621, 439/622
• US Class Current: 361/56
• CPC Class Codes: H01H 2085/0486 with voltage dependent resistor, e.g. varistor
• CPC Class Codes: H01H 85/44 Structural association with a spark-gap arrester

Abstract

A fuse block includes a body having a front face and a flat rear face. A plurality of terminal lugs mounted are on the front face, and a plurality of fuse clips are each connected to one of the terminal lugs. The terminal lugs and fuse clips are arranged in a plurality of pairs, each pair being positioned to receive a fuse. A plate receives the fuse block. The plate includes a front face and a rear face. The front face of the plate is flat and adapted to couple with the rear face of the fuse block. A plurality of metal straps are each affixed to the rear face of the plate and extend from the plate for termination into respective ones of each terminal lug pair. A single metal strap is also affixed to the rear face of the plate and extends from the plate for receiving a single terminal lug and a grounding wire. A plurality of metal oxide varistors are each connected between unique respective ones of the metal straps. A base has a sufficient depth for receiving the rear face of the insulating plate and the MOV'"'"'s mounted thereon and the fuse block.

Claims

1. A retrofit device for adding overvoltage protection to a fuse block having a plurality of terminal lugs affixed in pairs to one face of a flat insulating plate, the apparatus comprising:

a flat mounting plate separate from the fuse block and having a front face and a rear face;

a plurality of conductive straps each affixed to the rear face of the mounting plate and electrically isolated from each other, each conductive strap having a portion thereof extending from the rear face to the front face of the mounting plate for electrically connecting the strap to a terminal lug of the fuse block;

a grounding strap affixed to the rear face of the mounting plate and electrically isolated from the conductive straps, the grounding strap including means extending from the rear face of the mounting plate for receiving a grounding wire; and

an overvoltage protection circuit coupled to the conductive and grounding straps on the rear face of the mounting plate.

2. A device as recited in claim 1 wherein the overvoltage protection circuit includes a plurality of metal oxide varistors coupled to the conductive and grounding straps and forming an overvoltage protection circuit among the straps and ground.

3. An apparatus for providing overcurrent and overvoltage protection comprising:

a fuse block having a front and a rear, comprising a plurality of terminal lugs and associated fuse clips arranged in pairs on the front of the fuse block, each pair having a top terminal lug adapted to receive an input wire, a bottom terminal lug adapted to receive an output wire, a top fuse clip coupled to the top terminal lug and a bottom fuse clip coupled to the bottom terminal lug, said top and bottom fuse clips adapted to receive a fuse therebetween;

a plurality of conductive straps mounted on the rear of the fuse block, each strap being electrically coupled with respective ones of said top terminal lug and associated fuse clip;

a grounding strap mounted on the rear of the fuse block and including means for receiving a grounding wire;

an overvoltage protection circuit coupled to the conductive and grounding straps on the rear of the fuse block.

4. An apparatus as recited in claim 3 wherein the overvoltage protection circuit includes a plurality of metal oxide varistors coupled to the conductive and grounding straps and forming an overvoltage protection circuit among the straps and ground.

5. An apparatus for providing overcurrent and overvoltage protection comprising:

a fuse block including a plurality of terminal lugs and associated fuse clips, said terminal lugs and fuse clips being arranged in pairs, each pair adapted to receive a fuse and input and output wires;

a device including a mounting plate positioned adjacent the fuse block, a plurality of conductive straps each affixed to the mounting plate and having tabs extending outward and connected to each pair of terminal lugs, a grounding strap affixed to the mounting plate and including means for receiving a grounding wire, and an overvoltage protection circuit coupled to the conductive and grounding straps.

6. An apparatus as recited in claim 5 further comprising a cover enclosing the overvoltage protection circuit.

7. A method for retrofitting overvoltage protection to a fuse block, wherein the fuse block includes a plurality of terminal lugs mounted on a front face thereof and wherein the fuse block is mounted in an enclosure, the method comprising the steps of:

providing a retrofit device that includes a mounting plate, a plurality of conductive straps each affixed to one side of the mounting plate and each having tabs extending outwardly for connection to the terminal lugs of the fuse block, a grounding strap affixed to the one side of the mounting plate and including means for receiving a grounding wire, and an overvoltage protection circuit coupled to the conductive and grounding straps;

removing the fuse block from the enclosure;

coupling the retrofit device to a rear face of the fuse block by connecting the tabs to corresponding terminal lugs and a grounding wire to the grounding strap; and

reattaching the fuse block and retrofit device to the enclosure.