# US 6,293,821 B1 · Optional plug connector for a transfer switch having a terminal compartment > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,293,821 B1 - Document ID: US6293821B1 - Status: Granted - Kind: B1 - Application number: 09/062,257 - Filed: 1998-04-17 - Granted: 2001-09-25 - Earliest claimed: 1998-04-17 - Assignees: Reliance Controls Corporation - Inventors: David D. Flegel - Web page: https://patentgrep.com/patent/US6293821B1 ## CPC - H02B 1/50: Pedestal- or pad-mounted casings; Parts thereof or accessories therefor - H02B: BOARDS, SUBSTATIONS OR SWITCHING ARRANGEMENTS FOR THE SUPPLY OR DISTRIBUTION OF ELECTRIC POWER ## Abstract A power transfer device adapted for interconnection with the electrical system of a building includes a cabinet, a set of switches mounted to the cabinet, and a first set of wires for connecting the switches to an electrical distribution panel associated with the building electrical system. The power transfer device includes a terminal compartment associated with the cabinet, a set of power input terminals located within the terminal compartment, and a cover removably connected to the cabinet for alternatively preventing and permitting access to the terminal compartment. The cover is provided with a coupling arrangement adapted to be interconnected with the power input terminals, for selectively receiving an input member on one end of a flexible cord in electrical communication with a source of auxiliary power. ## Claims ### Claim 1 An auxiliary power supply system for supplying power to the electrical system of a building, comprising: a generator for supplying auxiliary power; a flexible power supply member interconnected with the generator and including a plug-type connector; and a power transfer device electrically interconnected with the building electrical system, wherein the power transfer device comprising: a housing; one or more switches mounted to the housing, wherein a power input conductor extends from each switch; a connection compartment defined by the housing, wherein the conductors terminate in a power input connection arrangement within the connection compartment at a location spaced from the switches; a cover arrangement interconnected with the power transfer device housing, including a fixed first cover section and a removable second cover section selectively engageable with the power transfer device housing over the connection compartment, wherein the second cover section is configured to cover the connection compartment to prevent access to the power input connection arrangement, wherein the switches are mounted to the housing at a location spaced from the second cover section; and power input structure provided on the removable second cover section, wherein the power input structure is separate from the power input connection arrangement; wherein the plug-type connector is selectively engageable with the power input structure for establishing an electrical connection of the generator to the power transfer device through the power input structure and the power input connection arrangement, and wherein the supply of auxiliary power to the building electrical system is controlled through the switches. ### Claim 2 (depends on 1) The auxiliary power supply system of claim 1, wherein the switches are mounted to the fixed first cover section. ### Claim 3 (depends on 1) The auxiliary power supply system of claim 1, wherein the power input connection arrangement comprises a set of power input terminals located within the connection compartment, wherein the power input conductors are connected to the set of power input terminals. ### Claim 4 (depends on 3) The auxiliary power supply system of claim 3, wherein the power input structure is electrically interconnected with the set of power input terminals by means of a set of power input wires extending between the power input structure and the set of power input terminals. ### Claim 5 (depends on 3) The auxiliary power supply system of claim 3, wherein the connection compartment opens in a forward direction and wherein the first cover section includes a rearwardly extending edge adjacent the connection compartment. ### Claim 6 (depends on 5) The auxiliary power supply system of claim 5, wherein the second cover section has a rearwardly extending ledge engageable with the rearwardly extending edge of the first cover section, and a vertically extending wall depending from the ledge and engageable with an end wall defined by the first cover section. ### Claim 7 (depends on 6) The auxiliary power supply system of claim 6, wherein the ledge is recessed to accommodate the set of power input terminals when the second cover section is engaged with the first cover section to cover the connection compartment. ### Claim 8 (depends on 6) The auxiliary power supply system of claim 6, wherein the power input structure extends through and is fixed to the vertically extending wall of the second cover section. ### Claim 9 (depends on 6) The auxiliary power supply system of claim 6, wherein the power input structure includes a cylindrical body and a circular collar adapted to overlie the vertically extending wall of the second cover section. ### Claim 10 An auxiliary power supply system for interconnection with the electrical system of a building, comprising: a generator for supplying electrical power; a flexible cord interconnected with the generator, wherein the flexible cord has an input member; and a power transfer device including: a cabinet; a set of switches mounted to the cabinet; a first set of wires interconnected between the switches and an electrical distribution panel associated with the building electrical system; a fixed position panel forming a part of the cabinet; a terminal compartment defined by the cabinet, wherein the terminal compartment is spaced from the switches and is accessible through an opening defined by the fixed position panel; a set of power input terminals located within the terminal compartment; a removable cover selectively engageable with the cabinet, wherein the removable cover is configured to close the opening when engaged with the cabinet for selectively preventing and providing access to the terminal compartment; and a power input coupling arrangement carried by the removable cover and separate from the set of power input terminals, wherein the power input coupling arrangement is adapted to be electrically interconnected with the power input terminals and selectively receives the input member of the flexible cord to supply power to the power transfer device through the coupling arrangement and the set of power input terminals. ### Claim 11 (depends on 10) The auxiliary power supply system of claim 10, wherein the power input coupling arrangement is adapted to be electrically interconnected with the power input terminals by means of a set of power input wires extending therebetween. ### Claim 12 (depends on 10) The auxiliary power supply system of claim 10, wherein the power input terminals are connected to the switches by a second set of wires. ### Claim 13 (depends on 10) The auxiliary power supply system of claim 10, wherein the cabinet includes a set of tabs spaced along an end wall thereof, the tabs having apertures formed therein. ### Claim 14 (depends on 13) The auxiliary power supply system of claim 13, wherein the cover includes a set of openings alignable with the apertures in the tabs. ### Claim 15 (depends on 14) The auxiliary power supply system of claim 14, wherein a set of fasteners is passed through the openings in the cover and is threadably engageable with the apertures in the tabs. ### Claim 16 (depends on 15) The auxiliary power supply system of claim 15, wherein one of the fasteners is used to secure the coupling arrangement to the cover. ### Claim 17 A method for constructing a power transfer device for supplying power from a generator to the electrical system of a building, the method comprising the steps of: providing a cabinet having a fixed position panel defining an opening providing access to a connection compartment within which a power input connection arrangement is located; equipping the cabinet with a plurality of switches electrically connected to the power input connection arrangement, wherein the switches are adapted for connection to the building electrical system and are operable to control the supply of power from the power transfer device to the building electrical system; providing a first removable cover member adapted for removable mounting to the cabinet, wherein the first cover member is incapable of power input and is configured to close the opening when mounted to the cabinet for selectively enclosing the power input connection arrangement; providing a second removable cover member having a power input structure separate from the power input connection arrangement, wherein the second cover member is adapted for removable mounting to the cabinet and is configured to close the opening when mounted to the cabinet for selectively enclosing the power input connection arrangement; and selecting one of the first cover member and the second cover member and mounting the selected one of the cover members to the cabinet over the connection compartment; wherein the step of mounting the second cover member includes electrically interconnecting the power input structure with the power input connection arrangement; and wherein, when the first cover member is mounted to the cabinet, a set of power input wires interconnected with the generator are supplied to the cabinet and are connected to the connection arrangement.