SYSTEMS AND METHODS FOR TRANSFERRING HEAT GENERATED IN AN ELECTRICAL ENCLOSURE

Abstract

A system for transferring heat generated in an electrical enclosure includes test busbars, a thermally conductive plate, and at least one contact assembly secured to the plate. Each pair of adjacent busbars is separated by a gap. The plate has at least one hole extending through it, and the test busbars are inserted through at least this hole. The contact assembly has separate fingers that partially cover at least the hole in the plate, and the adjacent fingers define a groove. Each finger is positioned in a gap between adjacent busbars, and each test busbar is positioned in a groove when the fingers are placed in the gaps between adjacent busbars. The test busbars and contact assembly fingers are oriented in an alternating pattern.

Description

SYSTEMS AND METHODS FOR TRANSFERRING HEAT GENERATED IN A / Qbfrnn / eznz / e / Y ELECTRICAL ENCLOSURE Field of Invention The field of description refers, in general, to electrical enclosures and more specifically, to systems and methods for transferring the heat generated in an electrical enclosure. Background of the Invention The switchgear is an electrical enclosure or cabinet that houses electrical switching and interrupting devices, such as circuit breakers, fuses, and associated control equipment, along with busbars, power cables, and interconnections for electrical power distribution. The switchgear is arranged in a series of sections, each of which houses different components. For example, the switchgear may include a cable section and a circuit breaker section. The cable section and the circuit breaker section may be located on opposite sides of a busbar assembly. The circuit breaker section may include the compartments that house the circuit breaker in electrical connection with the busbar assembly and / or the compartments that house auxiliary control equipment. Each circuit breaker may be electrically connected to a busbar. Ref. 345300 Vertical busbar assembly by means of a series of vertical test distribution bars that carry the electric current between the vertical busbar and the circuit breaker. The sales and marketing of switchgear systems are highly competitive. Two technical attributes of switchgear that could predict market acceptance and associated commercial success are increased power density and a reduced receptacle area. Power density measures the amount of energy delivered by the switches in the switchgear and can be defined by the number of switches included in the switchgear or by the total amperage of the switches per unit volume of the switchgear enclosure. The switchgear is a heat-rated product and must undergo thermal testing and pass the results to be certified for operation.As a result, it is difficult to increase the energy density of the switching apparatus because increasing the energy density of the switching apparatus similarly increases the heat generated by the current flowing through the electrical components within the switching apparatus. This additional heat raises the temperature of the components. As the volume of the switching apparatus enclosure is reduced, the volume of ambient air within the enclosure is also similarly reduced. Consequently, it is challenging to dissipate the heat generated by the circuit breaker components using a relatively cool ambient airflow. Existing techniques attempt to dissipate the heat through selective ventilation of the enclosure or by increasing the amount of copper used to form the switching apparatus busbars.In general, ventilation is limited by the amount of natural airflow that can be generated within the switchgear cabinet. Additionally, the addition of copper typically consumes more space within the fixed enclosure volume, reducing the volume available for ambient air, and copper is an expensive solution given fluctuations in global installations. Consequently, improvements to the switchgear are desirable so that it can accommodate a reduced enclosure volume and effectively dissipate system heat at a faster rate than existing techniques. Brief Description of the Invention In one aspect, a system for transferring heat generated in an electrical enclosure housing a busbar assembly and a circuit breaker includes test busbars, a thermally conductive plate, and at least one contact assembly secured to the plate. The test busbars are configured to conduct an electrical current between the busbar assembly and the circuit breaker. Each pair of adjacent busbars is separated by a gap. The thermally conductive plate has at least one hole extending through it, and the plate receives the test busbars through at least this hole. The contact assembly has separate fingers that partially cover at least the hole in the plate, and the adjacent fingers define a groove.Each finger is placed in a space between adjacent distribution bars, and each test distribution bar is placed in a groove when the fingers are positioned in the spaces between adjacent distribution bars. The test distribution bars and contact mounting fingers are oriented in an alternating pattern. In another aspect, an electrical enclosure has a first end and a second end, and opposite sides extending between the first and second ends. The electrical enclosure includes an inner wall joining the sides of the electrical enclosure and extending between the first and second ends. The inner wall includes at least one thermally conductive plate having at least one hole extending through it. The electrical enclosure also includes at least one contact assembly secured to the thermally conductive plate. The contact assembly has separate fingers that partially cover at least the hole in the plate, and the adjacent fingers define a groove. The electrical enclosure also includes a busbar assembly positioned between the first end and the inner wall, and a circuit breaker positioned between the second end and the inner wall.The electrical enclosure also includes test busbars that extend between the busbar assembly and the cutout and pass through at least the hole in the thermally conductive plate. Each pair of adjacent busbars is separated by a gap. Each test busbar is positioned in a groove of at least one contact assembly, and each separate finger of at least one contact assembly is positioned in a gap between adjacent busbars. The test busbars and contact assembly fingers are oriented in an alternating pattern. In another aspect, a method for transferring heat generated in an electrical enclosure includes guiding test busbars extending between a busbar assembly and a circuit breaker in the electrical enclosure through a thermally conductive plate. The thermally conductive plate has one end secured to a metal side post extending along a periphery of the electrical enclosure. The thermally conductive plate is in contact with each of the test busbars. The method also includes generating heat in the test busbars by conducting a current through them and transferring the heat generated in the test busbars to the metal side post using the thermally conductive plate. Brief Description of the Figures Figure 1 shows a schematic cross-sectional side view of a portion of an example electrical enclosure. Figure 2 shows an enlarged view of the portion of the electrical enclosure in Figure 1. Figure 3 shows an isolated perspective view of a portion of the electrical enclosure shown in Figure 1, which displays a configuration of the test distribution bars housed in the electrical enclosure. Figure 4 shows an isolated perspective view of the test distribution bars shown in Figure 3 coupled with an example thermally conductive plate to transfer the heat generated in the electrical enclosure during operation. Figure 5 shows a partially enlarged exploded view of a portion of the thermally conductive i Qbfrnn / eznz / e / YiAi plate shown in Figure 4, which has an example contact assembly. Figures 6A and 6B show the isolated and front perspective views, respectively, of a second contact member included with the contact assembly shown in Figure 5. Figures 7A and 7B show isolated and front perspective views, respectively, of a first contact member included with the contact assembly shown in Figure 5. Figures 8A and 8B show isolated front views of the contact assembly shown in Figure 5, in a centered position and an offset position, respectively. Detailed Description of the Invention With reference to Figure 1, a schematic cross-sectional side view of a portion of an example electrical enclosure 100 is shown. In the example embodiment, the electrical enclosure 100 is a low-voltage switching apparatus 100. As used herein, the term switching apparatus refers to an electrical enclosure that includes electrical disconnect switches, fuses, or circuit breakers used to control, protect, and isolate electrical equipment. The term low voltage refers to switching apparatus that operates at voltages lower than 2 kV. i Qbfrnn / eznz / e / YiAi The connecting device 100 includes the cabinet body 102, which extends between a first end 104 and a second end 106 and defines the interior of the connecting device 100. The interior includes a first interior portion 108, a second interior portion 110, and an interior wall 112. The first edge 114 has a rectangular configuration and is oriented horizontally, extending between the first end 104 and the second end 106. The interior wall 112 extends vertically and joins the first edge 114 of the cabinet body 102 to a second edge (not shown) of the cabinet body 102 opposite the first edge 114. Like the first edge 114, the second edge has a substantially rectangular configuration. In the example orientation shown in Figure 1, the first edge 114 defines a top portion of the cabinet body 102, and the second edge defines a base of the cabinet body 102.However, in other embodiments, the connecting device 100 may have an alternative orientation and is not intended to be limited to the orientation shown in Figure 1. The inner wall 112 separates the first inner portion 108 from the second inner portion 110. The first inner portion 108 is defined by the inner wall 112, the first end 104, and the first and second edges. The second inner portion 110 is defined by the inner wall 112, the second end 106, and the first and second edges. i Qbfrnn / eznz / e / YiAi The first inner portion 108 includes a generally open portion 116 that houses cables and other auxiliary components of the switching apparatus 100 and a vertical extension busbar assembly 118 adjacent to the open portion 116. The busbar assembly 118 carries an electric current supplied from an external electrical source (not shown). The busbar assembly 118 may include a first busbar 118a and a second busbar 118b for each phase of a circuit breaker 122 housed in the second inner portion 110, which is described in more detail later. In other embodiments, the busbar assembly 118 may include more or fewer busbars for each phase. Each of the first and second busbars 118a, b supplies the electric current and / or receives the current from the circuit breaker 122, as described in more detail later.In the example embodiment, the busbar assembly 118 is located within the first inner portion 108 adjacent to the inner wall 112. The location of the busbar assembly 118 within the first inner portion 108 is not intended to be limited to the example embodiment and may vary to allow the switching apparatus 100 to function for its intended application. Furthermore, in some embodiments, the busbar assembly 118 may be isolated from the open portion 116 by a partition (not shown) separate from the inner wall 112 and located within the first inner portion 108. In other embodiments, the busbar assembly 118 may not be isolated within the first inner portion 108 from other switching apparatus components located within the open portion 116.The busbar assembly 118 can be located together in the open portion 116 with other components of the connecting apparatus located in the open portion 116. The second inner portion 110 includes a plurality of vertically separated components 120 positioned along the second end 106 of the cabinet body 102 between the first edge 114 and the second edge (not shown) opposite the first edge 114. In the example embodiment, each compartment 120 may be either a circuit breaker compartment 120a housing a circuit breaker (for example, the circuit breaker 122 shown in Figure 2) or an auxiliary compartment 120b housing electrical components (not shown), such as controls, relays, communication devices, indicators, and the like. Any number of circuit breaker compartments 120a and / or auxiliary compartments 120b may be included in the second inner portion 110 to enable the switching apparatus 100 to function for its intended application. The second interior portion 110 also includes the ventilation wall 124, which is separate from the interior wall 112. The ventilation wall 124 isolates, at least partially, the interior of each compartment 120 from the exhaust duct 126 that extends through the second interior portion 110 between the ventilation wall 124 and the interior wall 112. A first metal side post 128a and a second metal side post 128b (shown in Figure 3) extend adjacent to the exhaust duct 126 and along opposite sides of the cabinet body 110 between the first edge 114 and the second edge. The interior wall 112 extends between and joins the first and second metal side posts 128a and b. The exhaust channel 126 is defined by the ventilation wall 124, the inner wall 112 and the first and second metal side posts 128a, b. The cabinet body 102 may also include the plenum 130 positioned at the first edge 114 adjacent to the first inner portion 110. The plenum 130 includes the vent duct 132, which defines an opening exposed to the outside of the cabinet body 102. The plenum 130 also includes an inlet 134 seamlessly connected to the exhaust channel 126 and an inner passage 136 extending through the plenum 130 from the inlet 134 to the vent duct 132. Together, the exhaust channel 126 and the plenum 130 allow the flow of cooling air, and / or gases and other unwanted emissions formed in the second inner portion 110, to flow through the exhaust channel 126 and out of the cabinet body 102 as the Gi gas flow.In some embodiments, an inner portion i Qbfrnn / eznz / e / YiAi 138 (shown in Figure 2) of the circuit breaker compartment 120a may be seamlessly connected to the exhaust channel 12 6 so that gases formed during operation of the circuit breaker 122 flow out of the cabinet body 102 and are carried along in the gas flow Gi. Cooling air may be supplied and directed through the exhaust channel 126 by the fan module (not shown) included within or adjacent to the first inner portion 110. In some embodiments, the fan module may be an integral component of one or more of the compartments 120. In other embodiments, the fan module may be a separate component included within or adjacent to the first inner portion.The plenum 130 may also include a second inlet (not shown) that is seamlessly connected to the first inner portion 108 to allow gases and other emissions formed in the first inner portion 108 to flow through the plenum 130 (e.g., through the inner passage 136) and out of the cabinet body 102 through the exposed outward opening of the vent duct 132. With reference to Figure 2, an enlarged view is shown of a portion of the breaker compartment 120a and a portion of the first and second busbars 118a, b of the switching apparatus 100 (shown in Figure 1). As shown in Figure 2, the breaker compartment 120a houses the breaker 122 in an internal portion 138 of the compartment 120a. The breaker 122 is electrically connected to the busbar assembly 118 by means of separate test busbar assemblies 140a and 140b. In the example configuration, the breaker 122 is a three-phase breaker 122. For each phase of the breaker 122, a pair of disconnects 144a and 144b are provided.For each phase, a first set of test busbars 140a is connected at one end to a first busbar 118a and at the other end to the piercing probes 142a inserted into the disconnect 144a of the respective phase. For each phase, a second set of test busbars 140b is connected at one end to a second busbar 118b and at the other end to the piercing probes 142b inserted into the disconnect 144b of the respective phase. Each of the test distribution bars 140a, b extends between the respective bus bar 118a, b and the circuit breaker compartment 120a through the inner wall 112, the exhaust channel 126 and the ventilation wall 124. In each set of test distribution bars 140a, b, pairs of adjacent distribution bars 140a and pairs of adjacent distribution bars 140b are separated by a space.With further reference to Figures 3 and 4, the three sets of test busbars 140a that correspond to each phase of the cutout 122 are aligned along axis Ai and are located between the first and second side posts 128a and 128b. Similarly to the test busbars 140a, the test busbars 140b are located between the side posts 128a, 128b and are aligned along axis Ai. Test busbars 140a and test busbars 140b extend through the inner wall 112 and the exhaust channel 126. Each set of separate test busbars 140a is aligned with a set of separate test busbars 140b along a Bi axis that extends substantially, perpendicular to the Ax axis between the first edge 114 and the second edge of the connecting apparatus 100.The test busbar assembly 140a and the test busbar assembly 140b, which are aligned along the Bx axis, correspond to the same phase of the cutout 122. In the example embodiment, each of the test busbars 140a and 140b comprises an L-shaped plate body, and the bodies of all the test busbars 140a and 140b are substantially the same size and shape and are positioned in a substantially parallel orientation. In other embodiments, the test busbars 140a and 140b may have different sizes, shapes, and / or orientations that allow the test busbars 140a and 140b to function as described herein. During operation, current Ei is supplied from busbar 118a and flows through test busbars 140a and through piercing points 142a to cutout 122. Current E2 flows from cutout 122 through piercing points 142b and through test busbars 140b to busbar 118b. Together, cutout 122, test busbars 140a, and piercing points 142a, b define an electrical circuit between busbars 118a and 118b and, as such, can be used to interrupt the flow of current between busbars 118a and 118b. The 122 cutout is rated to operate at a specified amperage, which determines the amount of current E2 and E2 flowing between bus bar 118a and bus bar 118b for each respective phase that can be effectively handled by the 122 cutout during normal operation.As the amperage rating of the 122 circuit breaker increases, the 122 circuit breaker can effectively operate with a larger amount of the E2y E2 current. The increased amount of E2y E2 current flowing into and from the 122 circuit breaker highlights the heat generation in the circuit components (e.g., the bus bars i Qbfrnn / eznz / e / YiAi). 118a, b, the test busbars 140a, b, the piercing tips 142a, b, and / or the disconnect points 144a, b). In general, for the purpose of the connecting apparatus 100 to be properly considered a heat-rated device by operation, the heat generated in each of the circuit components must not cause the component temperature to exceed the predetermined temperature rise limit, which may be imposed or otherwise determined by regulatory standards. A particular challenge in the design of a properly heat-rated connecting apparatus 100 is maintaining the temperature of the test busbars 140a, b within the predetermined temperature rise limit.In some examples, the default temperature rise limit for test busbars 140a, b may be from approximately 55°C (131°F) to approximately 95°C (203°F), or from approximately 65°C (149°F) to approximately 85°C (185°F). In these examples, the heat generated in the test busbars 140a, b may cause the temperature of the test busbars 140a, b to reach or exceed approximately 60°C (140°F) to approximately 100°C (212°F), or from approximately 70°C (158°F) to approximately 90°C (194°F).While the test distribution bars extending 140a, b through the exhaust channel 126 can help mitigate temperature increases in the test distribution bars 140a, b by exposing them to the relatively cool air flowing through the exhaust channel 126, these measurements cannot satisfactorily transfer a sufficient amount of heat from the test distribution bars 140a, b to maintain the temperatures of the test distribution bars 140a, b within the predetermined limit. Accordingly, with reference to Figures 3-8B, an example system 200 for transferring heat generated in the connecting apparatus 100 is shown. The system 200 includes the thermally conductive plates 202 which, when installed in the connecting apparatus 100, are in contact with and configured to transfer heat from the test busbar assemblies 140a and / or the test busbar assemblies 140b. In the example embodiment, the system 200 includes one thermally conductive plate 202 for the test busbar assemblies 140a and one thermally conductive plate 202 for the test busbar assemblies 140b.In this embodiment, each of the thermally conductive plates 202 associated with any of the test busbars 140a or 140b is in contact with, and transfers heat from, the respective test busbar assemblies 140a or test busbar assemblies 140b. In other embodiments, a single thermally conductive plate 202 may be in contact with, and transfer heat from, both the test busbar assemblies 140a and the test busbar assemblies 140b. The thermally conductive plate 202 is suitably formed from a thermally conductive material, such as, for example, aluminum. The thermally conductive plates 202 have identical constructions and are collectively referred to hereafter as plate 202. Plate 202 extends along an axis A2 from a first end of plate 204 to a second end of plate 206. An axis B2 extends substantially perpendicular to axis A2 through plate 202. Plate 202 can be installed in the connecting apparatus 100 by securing the first end of plate 204 with the first metal side post 128a and the second end of plate 206 with the second metal side post 128b. When plate 202 is installed in the connecting apparatus 100, axis A2 extends parallel to axis A2 and axis B2 extends parallel to axis B2. Additionally, plate 202 is installed and positioned to intercept the respective test busbar assemblies 140a or 140b that extend from busbar assembly 118 to cutout compartment 120a.In the example embodiment, plate 202 forms part of the inner wall 112 at the location where the respective test busbar assemblies 140a or 140b extend through it. The remainder of the inner wall 112 can be constructed from a plurality of molded plastic plates 148, each of which is secured to the first and second metal side posts 128a, b. The molded plastic plates 148 and plate 202 can be dimensioned similarly; for example, each can have a similar height relative to the Bx axis. Together, the molded plastic plates 148 and plate 202 facilitate the modular design of the inner wall 112.In other embodiments, plate 202 may be separated from the inner wall 112 and secured to the first and second metal side posts 128a, b, or at another location, so that plate 202 intercepts the respective test busbars 140a or 140b to enable plate 202 to function as described herein. Plate 204 has a face surface 208. In the example embodiment, face surface 208 is oriented towards the vent wall 124 when plate 202 is installed in the connecting apparatus 100. In other embodiments, face surface 208 may have a different orientation; for example, face surface 208 may be oriented towards the busbar assembly 118 when plate 202 is installed in the connecting apparatus 100. i Qbfrnn / eznz / e / YiAi With reference to Figure 5, plate 202 has a rectangular recessed portion 210 formed on the face surface 208. Each recessed portion 210 extends the entire lateral dimension of plate 202 along axis B2, and the recessed portions 210 are spaced apart along the length of plate 202 along axis A2. A hole 212 is formed in plate 202 in each recessed portion 210, and each hole 212 extends through plate 202 in a direction perpendicular to both axes A2 and B2. Plate 202 receives one of the test busbar assemblies 140a or 140b through each hole 212. In this way, the test busbars 140a and 140b extend through plate 202 and thereby extend through the inner wall 112 into the exhaust channel 126 (shown in Figure 3).In this respect, the position and number of recessed portions 210 and the position and number of holes 212 correspond to the position and number of test busbar assemblies 140a or 140b extending through plate 202. Accordingly, in the example embodiment, plate 202 includes three recessed portions 210 and three holes 212. A portion of each of the test busbars 140a or 140b extending through the respective hole 212 is covered by an electrically insulating material 146. The electrically insulating material 146 may include, for example, an epoxy coating, an epoxy sleeve, or a heat-shrink tube. Each hole 212 can be sized so that test busbars 140a or 140b extend from it with little or no contact between plate 202 and test busbars 140a and 140b. System 200 also includes contact assemblies 214, each of which is configured to make contact with one of the test busbar assemblies 140a or 140b extending through one of the holes 212 in plate 202. Appropriately, both plate 202 and contact assemblies 214 are formed from a thermally conductive material (e.g., aluminum). The contact assemblies 214 have an identical construction and are described collectively hereafter as the contact assembly 214. The contact assembly 214 is secured to the plate 202 and is seated in a respective recessed portion 210. The contact assembly 214 includes a first contact member 216a (shown in Figures 7A and 7B) that is secured to the plate 202 and a second contact member 216b (shown in Figures 6A and 6B) that is secured to the first contact member 216a.Each of the first and second contact members 216a, b has a rectangular body 222a, b that defines the opposite face surfaces 218a and 218b, respectively. When assembled, an i Qbfrnn / eznz / e / YiAi of the face surfaces 218a of the first contact member. 216a is oriented towards and in contact with the face surface 208 of the plate 202 in the recessed portion 210, and the other of the face surfaces 218a is oriented towards and in contact with one of the face surfaces 218b of the second contact member 216b that is secured to the first contact member 216a. Each contact member 216a, b has the separated fingers 220a, b formed in the body 222a, b. Each pair of adjacent fingers 220a and adjacent fingers 220b is separated by a notch, so that the separated fingers 220a, b define a series of notches in the contact member 216a, b. Each contact member 216a, b also includes the openings 224a, b and the holes 226a, b formed in the body 222a, b of the respective contact member 216a, b. Each of the openings 224a, b and the holes 226a, b extends through the opposite face surfaces 218a, b of the respective contact member 216a, b. The contact members 216a, b are dimensioned similarly. Each of the openings 224a of the first contact member 216a aligns with a respective opening 224b of the second contact member 216b. Each alignment pair of openings 224a, b receives a fastener 228 (for example, a bolt or screw) to secure the first and second contact members 216a, b, thus forming the contact assembly 214. When the contact assembly 214 is formed, each of the holes 226a of the first contact member i Qbfrnn / eznz / e / YiAi 216a is aligned with a respective hole 226b of the second contact member 216b to define the holes 230 that extend through the contact assembly 214. The plate 202 has the drilled holes 232 (shown in Figure 5) formed in the recessed portion 210 that correspond with and align with the holes 230 of the contact assembly 214. Each set of alignment holes 230 and drilled hole 232 receives a fastener 234 to secure the contact assembly 214 to the plate 202. When the contact assembly 214 is formed, each of the separate fingers 220a of the first contact member 216a aligns with a finger 220b of the second contact member 216b. The pairs of alignment fingers 220a, b form separate fingers 236 of the contact assembly 214. Each pair of adjacent fingers 236 is separated by a notch 238, so that the separate fingers 236 define a series of the notches 238 in the contact assembly 214. The fingers 236 partially cover the hole 212 when the contact assembly 214 is secured to the plate 202 in the recessed portion 210. The fingers 236 are sized and oriented so that the notches 238 receive one of the test distribution bars 140a or 140b extending through the hole 212.Therefore, when the contact assembly 214 is seated in a recessed portion 210, each of the separate fingers 236 is positioned in a space between the adjacent distribution bars 140a or the adjacent distribution bars 140b, and each of the test distribution bars 140a, b is positioned in a groove 238 when the fingers 236 are positioned in the space of the test distribution bar, so that the test distribution bars 140a, b and the contact assembly fingers 236 are oriented in an alternating pattern. Each of the fingers 236 extends along the body of the test distribution bar 140a or 140b located in a groove 238 adjacent to the respective finger 236.In general, the slots 238 are dimensioned, i.e., they have a suitable width that extends between the adjacent fingers 236, so that each of the fingers 236 makes contact with a portion of an adjacent test distribution bar 140a or 140b. In the example configuration, two contact assemblies 214 are seated in each recessed portion 210. The contact assemblies 214 seated in each recessed portion 210 are oriented so that the fingers 236 of one of the contact assemblies 214 face and align with the fingers 236 of the other contact assemblies 214. This forms pairs of alignment notches 238 of the contact assemblies 214. Each of the test distribution bars 140a, b is positioned in a space formed by a pair of alignment notches 238 when the contact assemblies 214 are seated in the recessed portions 210. i Qbfrnn / eznz / e / YiAi Each test busbar 140a or 140b located in a pair of alignment slots 238 has an upper and a lower portion. The first of the two contact assemblies 214 seated in a respective recessed portion 210 has its spread fingers 236 interleaved with the upper portion of the test busbars 140a, b located in the pair of alignment slots 238. The second of the two contact assemblies 214 has its spread fingers 236 interleaved with the lower portion of the test busbars 140a, b located in the pair of alignment slots 238. Whereupon each of the test busbars 140a, b located in a pair of alignment slots 238 may be substantially or entirely enclosed by the adjacent fingers 236 of each of the two contact assemblies 214.In other embodiments, the alignment fingers 236 of the two contact assemblies 214 seated in each recessed portion 210 can be joined together to form a single contact assembly (not shown). The portion of each test busbar 140a or 140b in contact with an adjacent finger 236 is covered by the electrically insulating material 146. The thickness of the electrically insulating material 146 may vary. As a result, the width of the slit 238 that is suitable for establishing contact between each finger 236 and the test busbar 140a or 140b may also vary. The contact assembly 214 allows the width of the slots 238 to be adjusted to account for variations in the thickness of the electrically insulating material 146. In the example embodiment, when the contact assembly 214 is formed and secured to the plate 202, the second contact member 216b can move along axis A2 relative to the first contact member 216a and the plate 202. Each of the openings 224b and holes 226b is sized to allow movement of the second contact member 216b.More specifically, each of the openings 224b has a width Yt, which is larger than a width Ya of the openings 224a of the first contact member 216a, and each of the holes 226b has a width Xb, which is larger than a width X of the holes 226a and a width (not shown) of the holes 232 in the plate 202. As a result, the second contact member 216b can move around the fasteners 228 and 234 along axis A2. In the example embodiment, the second contact member 216b can move along axis A2 when the contact assembly 214 is secured to the plate 202 and the first contact member 216a is fixed and cannot move along axis A2. Alternatively, in other configurations, the first contact member 216a can move along axis A2 as described above for the second contact member. 216b and the second contact member 216b can be fixed and cannot move along axis A2. Still in other embodiments, both of the first contact member 216a and the second contact member 216b can move along axis A2. The recessed portion 210 in which the contact assembly 214 is seated is appropriately dimensioned so that one or both of the contact members 216a, b can move within the recessed portion 210 to allow the contact assembly 214 to function as described herein. With reference to Figures 8A and 8B, the movement of the second contact member 216b along axis A2 causes the contact assembly 214 to adjust between a centered position (shown in Figure 8A) and an offset position (shown in Figure 8B). In the centered position, each of the fingers 220a of the first contact member 216a aligns with a respective finger 220b of the second contact member 216b, such that the fingers 236 of the contact assembly 214 define the grooves 238 that have a width Z2. In the deflected position, each of the fingers 220a of the first contact member 216a and the respective fingers 220b of the second contact member 216b are displaced or deflected, so that the fingers 236 of the contact assembly 214 define the slots 238 that have a width Z2. The width d2 is smaller than the width d2.Starting from the centered position, the contact assembly 214 can be adjusted to the offset position by moving the second contact member 216b along axis A2 towards a first end 204 of the thermally conductive plate 202, or towards a second end 206 of the thermally conductive plate 202, to offset the fingers 220a, b of the contact members 216a, b. The contact assembly 214 can be adjusted back to the centered position from the offset position by moving the second contact member 216b along axis A2 towards the other end 206 or 204, to align the fingers 220a, b of the contact members 216a, b.Adjusting the contact assembly 214 between the centered position and the offset position allows selective adjustment of the width of each of the slots 238 to properly establish contact between each of the fingers 236 of the contact assembly 214 and an adjacent test distribution bar 140a or 140b, depending on the thickness of the electrically insulating material 146. With reference to Figures 1-8B, a method for transferring the heat generated in the switching apparatus 100 will be described below. As described above, the busbar assembly 118 is electrically connected to the circuit breaker 122 by means of the test busbars 140a, b that extend from the first inner portion 108, through the inner wall 112, to the second inner portion 110. The inner wall 112 can be assembled by securing a series of molded plastic plates 148 to the metal side posts 128a, b that extend along the sides of the cabinet body 102 of the switching apparatus 100.Furthermore, the portions of the inner wall 112 through which the test busbars 140a, b are formed are extended by means of the thermally conductive plates 202, each of which is secured at the first end 204 with the first metal side post 128a and at the second end 206 with the second metal side post 128b. The contact assemblies 214 secured in the thermally conductive plate 202 can be adjusted as described above, so that each of the slots 238 receiving one of the test busbars 140a and / or 140b has a width suitable for establishing contact between each of the fingers 236 of the contact assemblies 214 and the adjacent test busbar(s) 140a and / or 140b extending through the slot(s) 238 adjacent to each finger 236.During operation, heat H is generated in the test distribution bars 140a, b by conducting a current E2o E2a through each of the test distribution bars 140a, b. The plates 202 and the contact assemblies 214 are formed from a thermally conductive material (e.g., aluminum) and transfer the heat H generated in the test busbars 140a, b to one or both of the metal side posts 128a, b. For example, the metal side posts 128a, b, which may be exposed to ambient or near-ambient temperature conditions, may act as a heat sink relative to the test busbars 140a, b, which are at a higher temperature relative to the temperature of the side posts 128a, b during operation. Heat H is conducted through each of the fingers 236 of the contact assemblies 214 that are in contact with an adjacent test distribution bar 140a or 140b and through the plate 202 of the thermally conductive plate 202, to the metal side posts 128a, b.As previously described, a portion of each of the test busbars 140a, b that is in contact with the adjacent finger 236 is covered with an electrically insulating material. This allows heat H to be transferred from the test busbars 140a, b to the metal side posts 128a, b through the thermally conductive plate 202 without the electric current Ei or E2 being conducted between them. The previously described embodiments of systems and methods for transferring heat generated in an electrical enclosure provide technical advantages by facilitating lower temperatures in the electrical components within the enclosure during operation. More specifically, the embodiments described herein provide a thermally conductive plate that can be selectively adjusted to make contact with the test busbars connecting the busbars and circuit breakers within the electrical enclosure and to transfer the heat generated in the test busbars to cooler structural elements along or near the periphery of the electrical enclosure.This facilitates increasing the amount of heat that can be dissipated from the test busbars, which could otherwise pose a greater risk of exceeding the predetermined temperature rise limits for heat-rated enclosures during operation. Furthermore, the thermally conductive plate, according to at least some embodiments of this description, is designed as a modular component (e.g., an interior wall) that is part of existing electrical enclosures. In this respect, existing electrical enclosures can be retrofitted with the example configurations or features described herein to allow the systems and methods described herein to be implemented by and / or within the existing electrical enclosures. Consequently, the systems and methods described herein facilitate an increase in the energy density of the switching apparatus, allowing greater energy to flow through the system without increasing the overall volume of the switching apparatus enclosure. As such, circuit breakers with higher current ratings, and / or a larger number of circuit breakers, can be installed in the switching apparatus system without substantial reconfiguration or redesign. Additionally, the systems and methods can facilitate a reduction in the amount of copper used in the switching apparatus system because the conductive components are cooled more efficiently, thereby increasing the product margin of the switching apparatus.Additionally, the systems and methods can facilitate the reduction of the enclosure volume of existing connection equipment since the conductive components (e.g., test distribution bars) are cooled more efficiently and the reduced amount of ambient air is adequate to keep the temperatures of the conductive components within predetermined temperature rise limits. Other variations to the described embodiments may be understood and implemented by persons skilled in the art of practicing the claimed invention, based on a study of the figures, the description, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" does not exclude a plurality. The mere fact that certain measurements are indicated in the mutually different dependent claims does not indicate that the combination of these measurements cannot be used to an advantage. Any reference numbers in the claims shall not be construed as limiting the scope of the claims. While the invention has been illustrated and described in detail in the figures and description above, this illustration and description are to be considered illustrative or exemplary and not restrictive. It is understood that changes and modifications may be made by persons of ordinary experience within the scope of the following claims. In particular, the present invention covers additional embodiments with any combination of features of the different embodiments described above and below. Furthermore, the statements made herein characterizing the invention relate to one embodiment of the invention and not necessarily to all embodiments. The terms used in the claims should be interpreted to have the broadest reasonable interpretation consistent with the preceding description. For example, the use of the article "a" or "the" in the introduction of an item should not be interpreted as being exclusive to a plurality of items. Similarly, the reference to "or" should be interpreted as being inclusive, so that the reference to A or B is not exclusive to A and B, unless it is clear from the context or the preceding description that only one of A and B is intended. Furthermore, the reference to "at least one of A, B, and C" should be interpreted as one or more of a group of items consisting of A, B, and C and should not be interpreted as requiring at least one of each of the listed items A, B, and C, regardless of whether A, B, and C are related as categories or otherwise.Likewise, the designation of A, B and / or C or at least one of A, B or C should be interpreted as including any single entity of the listed items, e.g., A, any subset of the listed items, e.g., A and B, or all of the listed items A, B and C. This written description uses examples to illustrate the invention, including the best manner, and also to enable any person skilled in the art to practice the invention, including the making and use of any type of device or system and the implementation of any type of incorporated methods. The patentable scope of the invention is defined by the claims and may include other examples that will occur to those skilled in the art. These other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims. It is hereby stated that, as of this date, the best method known to the applicant for putting the aforementioned invention into practice is the one that is clear from the present description of the invention.

Claims

1. A system for transferring heat generated in an electrical enclosure housing a busbar assembly and a circuit breaker, characterized in that it comprises: test busbars configured to conduct an electric current between the busbar assembly and the circuit breaker, each pair of adjacent busbars being separated by a space; a thermally conductive plate having at least one hole extending through it, wherein the plate receives the test busbars through at least the hole;and at least one contact assembly secured to the plate, at least the contact assembly having separate fingers that partially cover at least the hole in the plate, wherein the adjacent fingers define a groove, each of the fingers being located in a space between adjacent distribution bars and each of the test distribution bars being located in a groove when the fingers are located in the spaces between adjacent distribution bars and wherein the test distribution bars and the contact assembly fingers are oriented in an alternating pattern.

2. The system according to claim 1, characterized in that the plate includes a shaft and wherein at least the contact assembly comprises a first contact member secured to the plate and a second contact member secured to the first contact member, wherein each of the first and second contact members comprises separate fingers that each align with a finger of the other contact member to form the fingers of at least the contact assembly, wherein one of the contact members can be moved relative to the thermally conductive plate along the shaft to deflect the fingers of the first contact member and the fingers of the second contact member.

3. The system according to claim 2, characterized in that one of the contact members can be moved relative to the plate along the axis such that at least the contact assembly is adjustable between them: a centered position in which the fingers of the first contact member are aligned with the fingers of the second contact member to form the fingers of at least the contact assembly, wherein each of the indentations defined by the adjacent fingers of at least the contact assembly has a first width; and an offset position in which the fingers of the first contact member and the fingers of the second contact member are offset to form the fingers of at least the contact assembly, wherein each of the indentations defined by the adjacent fingers of at least the contact assembly has a second width that is smaller than the first width of the respective indentation.

4. The system according to claim 3, characterized in that at least the contact assembly can be adjusted between the centered position and the offset position, such that a width of each of the slots defined by the adjacent fingers of at least the contact assembly is dimensioned to establish contact between the adjacent fingers defining a slot and the test distribution bar that is located in the slot.

5. The system according to claim 2, characterized in that each of the contact members comprises at least one opening that aligns with an opening of the other contact member, wherein the alignment openings receive a fastener to secure the contact members to form at least the contact assembly, and wherein at least the opening of one of the contact members that can be moved relative to the plate along the axis is dimensioned to allow one of the contact members to move relative to the other of the contact members.

6. The system according to claim 2, i Qbfrnn / eznz / e / YiAi characterized in that each of the contact members comprises at least one hole that aligns with at least one hole of the other contact member, wherein the plate comprises at least one drill that aligns with the alignment holes of the contact members, wherein the alignment holes and the drill receive a fastener for securing the contact members to the plate, and wherein at least the hole of one of the contact members that can be moved relative to the plate along the axis is dimensioned to allow one of the contact members to move relative to the other of the contact members and the plate.

7. The system according to claim 1, characterized in that it comprises a metal side post extending the length of the electrical enclosure, the thermally conductive plate being secured to the metal side post at a first end of the plate, and wherein the thermally conductive plate transfers the heat generated in each of the test busbars during the operation of each of the test busbars to the metal side post secured at the first end of the plate.

8. The system according to claim 1, characterized in that each of the plate and at least the contact assembly i Qbfrnn / eznz / e / YiAi are made of a thermally conductive material comprising aluminum.

9. The system according to claim 1, characterized in that a width of each of the slots defined by the adjacent fingers of at least the contact assembly is dimensioned to establish contact between the adjacent fingers defining a slot and a portion of the test distribution bar that is located in the slot, wherein the portion of the test distribution bar is covered by an electrically insulating material.

10. The system according to claim 9, characterized in that the electrically insulating material covering the portion of the test bus bar comprises an epoxy coating, an epoxy sleeve, or a heat-shrink tube.

11. The system according to claim 1, characterized in that the plate has at least one recessed portion, at least the hole is formed in at least the recessed portion, wherein at least the contact assembly secured in the plate is seated in at least the recessed portion.

12. The system according to claim 11, characterized in that the test distribution bars comprise three sets of test distribution bars, wherein the plate has three recessed portions and three holes, each of the holes being formed in one of the recessed portions, wherein each set of test distribution bars is received through one of the holes and wherein at least one contact assembly is seated in each of the recessed portions.

13. The system according to claim 11, characterized in that the test distribution bars have an upper portion and a lower portion, wherein a first contact assembly and a second contact assembly are each seated in at least the recessed portion, the first contact assembly having separate fingers interleaved with the upper portion of the test distribution bars, the second contact assembly having separate fingers interleaved with the lower portion of the test distribution bars.

14. An electrical enclosure having a first end and a second end and opposite sides extending between the first end and the second end, characterized in that it comprises: an inner wall joining the sides of the electrical enclosure and extending between the first end and the second end, the inner wall comprising at least one thermally conductive plate, the thermally conductive plate having at least one hole extending through it; at least one contact assembly secured to the thermally conductive plate, the contact assembly having separate fingers partially covering at least the hole in the plate, wherein the adjacent fingers define a slit; a busbar assembly positioned between the first end and the inner wall; and a circuit breaker positioned between the second end and the inner wall.and the test distribution bars extending between the busbar assembly and the cutout and extending through at least the hole in the thermally conductive plate, each pair of adjacent distribution bars being separated by a space, each of the test distribution bars being located in a groove of at least the contact assembly, each of the separate fingers of at least the contact assembly being located in a space between the adjacent distribution bars, wherein the test distribution bars and the contact assembly fingers are oriented in an alternating pattern.

15. The electrical enclosure according to claim 14, characterized in that it further comprises a first metal side post extending along one side of the electrical enclosure and a second metal side post extending along a side opposite the first side post, wherein the inner wall joins the first and second metal side posts and wherein the thermally conductive plate i Qbfrnn / eznz / e / YiAi transfers the heat generated in each of the test busbars during the operation of each of the test busbars to at least one of the first and second metal side posts.

16. The electrical enclosure according to claim 14, characterized in that the thermally conductive plate includes a shaft, wherein the contact assembly comprises a first contact member secured to the plate and a second contact member secured to the first contact member, wherein each of the first and second contact members comprises separate fingers that each align with a finger of the other contact member to form the fingers of the contact assembly, wherein one of the contact members can be moved relative to the plate along the shaft so that at least the contact assembly is adjustable between: a centered position in which the fingers of the first contact member align with the respective fingers of the second contact member to form the fingers of at least the contact assembly, wherein each of the indentations defined by the fingers of at least the contact assembly has a first width;and a deviated position where the fingers of the first contact member and the respective fingers of the second contact member are displaced to form the fingers of at least the contact assembly, where each of the slits defined by the fingers of at least the contact assembly has a second width that is smaller than the first width of the respective slit.

17. The electrical enclosure according to claim 16, characterized in that the plate has at least one recessed portion, at least the hole is formed in at least the recessed portion, wherein at least the contact assembly is seated in at least the recessed portion, wherein the at least the recessed portion is dimensioned so that one of the contact members can move within the recessed portion.

18. The electrical enclosure according to claim 14, characterized in that each of the plate and at least the contact assembly are made of a thermally conductive material comprising aluminum, wherein a portion of each of the test distribution bars is covered by an electrically insulating material and wherein each of the fingers of at least the contact assembly is in contact with the electrically insulated portion of an adjacent test distribution bar.

19. A method for transferring heat generated in an electrical enclosure, the electrical enclosure comprising a metal side post extending along a periphery i Qbfrnn / eznz / e / YiAi of the electrical enclosure, a busbar assembly, a circuit breaker, and test busbars extending between the busbar assembly and the circuit breaker, characterized in that it comprises: guiding each of the test busbars through a thermally conductive plate, the thermally conductive plate having a first end secured to the metal side post, wherein the thermally conductive plate is in contact with each of the test busbars; generating heat in the test busbars by conducting a current through the test busbars;and transfer the heat generated in the test distribution bars to the metal side post using the thermally conductive plate.

20. The method according to claim 19, characterized in that it further comprises covering the portion of each of the test distribution bars with an electrically insulating material, wherein the thermally conductive plate is in contact with the electrically insulated portion of each of the test distribution bars.

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