Electrical switching device and electrical protection system

Abstract

An electrical switching device comprising a pair of opposing circuit breakers (310a, 310b), each circuit breaker (310a, 310b) of the pair of opposing circuit breakers (310a, 310b) including an opposing end face (311a, 311b) with an exhaust outlet disposed therein, the switching device comprising: a switchboard configured to operatively support the pair of opposing circuit breakers (310a, 310b) to define a gap (401) therebetween; an insulating barrier (900) configured for functional arrangement in the intermediate space (401), comprising a first cantilevered wall element (911) arranged to define a first clearance region (931) having a first cross-sectional area and a second clearance region (932) having a second cross-sectional area; and wherein the insulating barrier (900) is operable to deflect in a first direction to thereby increase a first or second cross-sectional area in response to a leakage of ionized gases (65) from one of the pair of power switches (310a, 310b).

Description

BACKGROUND OF THE INVENTIONThe embodiments described herein relate generally to power plant protection devices and, more particularly, to devices employing a movable insulator for use in discharging ionized exhaust gases and pressure from a location of arc generation.Conventional switchboards have an electrical distribution apparatus for mounting a plurality of power switches for controlling the electrical distribution from a main to one or more branch circuits. Such switchboards typically have a wall mounted housing that supports conductive bus bars and electrical switching devices (e.g., without limitation, switching devices and circuit breakers such as power switches, contactors, motor starters, motor controllers, and other load controllers) electrically connected to the bus bars.Circuit breakers are often arranged in adjacent pairs in conventional circuit board assemblies and are connected in an end-opposed "dual-junction" arrangement to current carrying bus bars of the same electrical phase. Circuit breakers typically have an injection molded plastic housing that includes at least one pair of separable contacts. When the separable contacts are opened under overload, short circuit or fault conditions, an arc is generated which is accompanied by the generation of ionized gases. The temperatures of the ionized gas may reach or exceed 2100° C., which may vaporize the conductors and adjacent equipment. Furthermore, arcing can release a significant amount of energy in the form of heat, intense light, pressure waves, and / or sound waves sufficient to damage the conductors and adjacent equipment.Such ionized gases are conventionally discharged through exhaust outlet openings disposed in a circuit breaker housing and, when discharged from one circuit breaker in a dual-split arrangement, could be transferred to the other adjacent circuit breaker or to the bus bars, resulting in a phase-to-phase fault. The ionized gases could also cause a phase-to-earth fault with the metallic panel housing in which the circuit breaker is mounted.Prior art switchboard assemblies utilize fixed relatively rigid stationary barriers and non-expandable clearance between the opposing poles of a pair of dual-split mounted spaced circuit breakers in a polyphase power system to prevent a phase-to-phase electrical fault caused by ionized exhaust gases discharged from a circuit breaker phase from reaching or contacting other phase conductors in the power system.Although some conventional switchboards have included stationary barriers to protect the phase conductors from the emitted ionized gases, these barriers typically attempt to prevent the flow of exhaust gases past the barrier and are not adjustable or movable to operatively alter the proportion of the space on either side of the barrier in response to the ionized exhaust gases emitted during an arc event. In addition, other conventional barriers utilize more complex multi-piece barrier assemblies that increase cost. There is therefore a need for an improved simple, robust and inexpensive insulating barrier with minimal parts to be installed in a switchboard and to be operated to advantageously increase the volume of a clearance to receive the ionized gases emitted. Switchboards are known both from EP 1 498 921 A1 and from U.S. Pat. No. 8 519 287 B2.Accordingly, there is room for improvement in circuit protection systems having a movable insulating barrier for electrical switching devices and circuit board assemblies.Brief Description of the InventionIn one aspect, an electrical switching device is described having a pair of opposing circuit breakers, each circuit breaker of the pair of opposing circuit breakers including an opposing face with an exhaust outlet disposed therein. The switching device includes a switchboard for operatively supporting the pair of opposing circuit breakers to define a space therebetween and an insulative barrier configured for operative placement within the space and having a first cantilevered wall member to define a first space region having a first cross-sectional area and a second space region having a second cross-sectional area. The insulating barrier functions to deflect in a first direction to thereby increase a first or second cross-sectional area in response to ionized gases exiting a power switch of the pair of power switches. In certain embodiments, the insulating barrier includes a second cantilevered wall element in cooperation with the first cantilevered wall element to define the first free space region and the second free space region.The insulating barrier may further operate to simultaneously decrease the other of the first and second cross-sectional areas in response to ionized gases exiting a power switch of the pair of power switches.The insulating barrier of any aforementioned device may further comprise holding means adapted to hold the insulating barrier in the space in the operative position.The insulating barrier of any aforementioned device may further include a first outer wall member and a second outer wall member; and wherein the cantilevered wall member may be substantially perpendicularly connected to and interposed between the first and second outer wall members.The cantilevered wall member of any aforementioned device may further include a first flexible cross member configured to deflect in the first direction in response to an egress of ionized gases from a circuit breaker of the pair of circuit breakers.The flexible cross member of any of the aforementioned devices may be one of a pleat, a pleat, or a resilient member.The first flexible cross member of each aforementioned device may be further configured to subsequently allow a second deflection in a second direction of the first cantilevered wall member.The second direction may be opposite to the first direction.The insulating barrier of any aforementioned device may further include a second cantilevered wall element that cooperates with the first cantilevered wall element to define the first free space region and the second free space region.The first and second cantilevered wall members of each aforementioned device may each be configured to cooperatively deflect in a first direction to thereby increase one of the first and second cross-sectional areas in response to the egress of ionized gases from a circuit breaker of the pair of circuit breakers.The first and second cantilevered wall members of each of the aforementioned devices may further each be configured to subsequently cooperatively deflect in a second direction.The second direction may be opposite to the first direction.The first and second cantilevered wall elements of any aforementioned device may have respective first and second basal ends and respective first and second distal ends; and wherein the first and second cantilevered wall elements may be arranged to overlap at least a portion of the respective distal ends.Each of the first and second cantilevered wall members of each aforementioned device may be configured to be disposed substantially operatively opposite one of the end faces of the pair of circuit breakers and may be connected in flow communication with the corresponding exhaust outlet thereon.The insulating barrier of any aforementioned device may further include a first outer wall member and a second outer wall member; and wherein the basal end of the first cantilevered wall member may be connected to the first outer wall member and the basal end of the second cantilevered wall member may be connected to the second outer wall member.In another aspect, an electrical protection system having a pair of circuit breakers is described. The electrical protection system includes a housing for receiving the pair of power switches, the housing configured to operatively support the pair of power switches to define a space therebetween. An insulating barrier is configured for functional placement in the gap, including a first cantilevered wall member to define a first clearance region having a first cross-sectional area and a second clearance region having a second cross-sectional area. The insulating barrier functions to deflect in a first direction to thereby increase one of the first and second cross-sectional areas in response to an ionized gas exiting a power switch of the pair of power switches. In certain embodiments, the insulating barrier includes a second cantilevered wall element that cooperates with the first cantilevered wall element to define the first free space area and the second free space area.The insulating barrier of each electrical protection system may further operate to simultaneously decrease the other of the first and second cross-sectional areas in response to the ionized gases exiting a power switch of the pair of power switches.The insulating barrier of each aforementioned electrical protection system may further include a second cantilevered wall element that cooperates with the first cantilevered wall element to define the first clearance area and second clearance areas.The first and second cantilevered wall members of each aforementioned electrical protection system may each be configured to cooperatively deflect in a first direction to thereby increase one of the first and second cross-sectional areas in response to the ionized gases exiting a circuit breaker of the pair of circuit breakers.The first and second cantilevered wall members of each aforementioned protection system may be configured to subsequently deflect together in a second direction.Brief Description of the DrawingsFIG. 1 is a front view of an exemplary circuit protection system according to an embodiment, with the cover omitted for clarity. FIG. 2 is a perspective view of a portion of a circuit protection system according to an embodiment with the insulating barrier and various parts removed for clarity. FIG. 3 is a perspective view of a portion of a circuit protection system according to an alternative embodiment, with the insulating barrier and various parts omitted for clarity. FIG. 4 is an end view of an exemplary circuit protection system according to an embodiment. FIG. 5 is an end view of the embodiment of FIG. 4 in an operating state. FIG. 6 is an end view of an exemplary circuit protection system of FIG. 4 according to an alternative embodiment. FIG. 7 is an end view of the embodiment of FIG. 6 in an operating state. FIG. 8 is a perspective view of an embodiment of the insulating barrier that may be used with the embodiment of FIG. 4. FIG. 9 is a perspective view of an embodiment of the insulating barrier that may be used with the embodiment of FIG. 6.DETAILED DESCRIPTION OF THE INVENTIONExemplary embodiments of circuit protection systems and devices are described herein. These embodiments improve the quenching and control of gases, heat, and pressure exiting a circuit breaker after an arc is generated. These embodiments quench and control the flow of exhaust gases, heat and pressure from a circuit breaker included in the circuit protection system. Extinguishing and controlling the exhaust gases protects the circuit protection system and all other equipment positioned in the equipment housing from the flow of exhaust gases, heat and pressure.Although various embodiments are described herein with reference to an electrical switchboard assembly having one or more pairs of opposing three-pole circuit breakers, other contemplated embodiments are not so limited and may include other electrical power elements and systems such as load centers or similar current distribution devices having electrical switching devices such as single or multipolar circuit switching devices such as contactors, motor starters, motor controllers, and other load controllers.As used herein, the term "ionized" means fully or partially converted to ions and electrically conductive, such as ionized gases generated in response to an electrical fault.As used herein, the term "dual-junction" refers to a configuration of the electrical switching device having a circuit board, such as a pair of spaced-apart circuit breakers having multiple poles each, each of the poles of one of the spaced-apart circuit breakers having a respective opposite pole on the other of the spaced-apart circuit breaker such that each pair of respective opposite poles is electrically connected to an elongate bus bar carrying current of the same electrical phase.FIG. 1 illustrates a movable or deflectable insulative barrier 900 for use with a distribution device such as an electrical panel assembly 101. FIG. 1 illustrates an embodiment having two pairs of circuit breakers 310 a, 310 bmounted in the switchboard 101, with various redundant portions of the switchboard assembly 101 omitted for clarity.In one embodiment, the circuit board assembly 101 includes a support frame 113, main or phase rail conductors 136, 137, 138, and a plurality of corresponding shunt ribbon conductors 436, 437, or 438, and one or more circuit switch mounting bases 144. In various embodiments, the panel assembly 101 also includes a cabinet or housing 111 defining a housing interior portion 112 therein. In one embodiment, the panel assembly 101 includes a first end 101 aand a second opposing end 101 bthat define a first longitudinal axis X 1 extending therebetween.In one embodiment, the support frame 113 includes a pair of elongated spaced side rails 113a and a pair of spaced end rails 113b rigidly connected to the side rails 113a. In one embodiment, the support frame 113 is fixed in engagement with a rear wall 114 of the housing 111.In one embodiment, the housing 111 includes a first end 115 and an opposing second end 116. In various embodiments, the housing 111 includes the rear wall 114 and two opposing end walls 115 a, 116 bdisposed at the first end 115 and second end 116 of the housing 111, respectively, and disposed substantially perpendicular to the rear wall 114. The housing 111 may include two opposing spaced apart side walls 117, 118 extending between the end walls 115a, 116b and disposed substantially perpendicular to the rear wall 114. The housing 111 may further include a panel cover 119 spaced from and substantially parallel to the rear wall 114. In some embodiments, the cover may additionally include an interposer portion 119a configured to functionally prevent inadvertent access to live conductors in the housing 111. In other embodiments, a removable or openable non-intermediate panel portion 119b of the panel cover 119 is provided to allow a user access to other internal parts. Respective openings are formed in the intermediate plate 119a to allow the operating knobs 102 of the circuit breakers to extend therethrough. In some embodiments, an openable door (not shown) is arranged to cover the power switches corresponding to toggles in a first closed position and to provide access thereto in a second open position.In one embodiment, the main or phase bus conductors 136, 137, 138 are arranged as a plurality of spaced apart, substantially parallel elongated, substantially flat bus bars. For example, the first, second, and third elongated bus bars 136, 137, 138 are connected to and electrically isolated from the support frame 113 in the housing interior portion 112. Each phase conductor 136, 137, 138 is connected to a corresponding terminal 139 or other suitable connector for receiving incoming current, such as from an electrical cable.At least one respective branch ribbon conductor 436, 437 or 438 is operatively connected to a respective main bus or phase conductor 136, 137, 138. In one embodiment, the bus bars 136, 137, 138 and the branch ribbon conductors 436, 437, 438 may be rigidly connected by a fastener 439, such as a screw or rivet. For example, each main bus bar(s) or phase conductor 136, 137, 138 may be provided with a plurality of longitudinally spaced apertures 434 defined therethrough and dimensioned to receive the fastener 439. Likewise, the shunt ribbon conductors 436, 437, and 438 may also have an opening defined therethrough and defined to receive the fastener 439.A neutral arrangement 140 may also be included as part of the circuit board arrangement 101. In one embodiment, the neutral assembly 140 includes spaced parallel conductive rails 144 having a plurality of suitable terminals and screws. The neutral assembly 141 is fixed to a support frame 113. In one embodiment, the neutral assembly is disposed on the support frame 113 along its opposite longitudinal edges and a conductive element 142 extends between and electrically connects portions of the neutral assembly 140.In various embodiments, the switchboard assembly 101 also includes one or more insulative struts 118, such as an upper strut 18 aand a lower strut 18 bto prevent movement of the phase bus bars 136, 137, 138 during a fault condition. In one embodiment, the insulative struts (18) are formed of an insulative thermoplastic material such as Noryl and are rigidly attached to and bridge the phase bus bars 138, 137, 18. The struts 18 may also be rigidly attached to the side rails 113a, 113b.In one embodiment, one or more power switch mounting bases 144 are configured to align, support, and position a first power switch 310 aand a second power switch 310 bas a corresponding pair of power switches 310 a310 a, 310 bto be operatively connected to the phase bus bars 136, 137. The mounting base 114 may be formed of an insulating thermoplastic material, such as Noryl, and may be rigidly attached to and bridge the side rails 113a.In one embodiment, the circuit breaker mounting base 144 includes a plurality of upstanding elongated parallel divider walls 149 formed integrally therewith. The divider walls 149 define branch belt compartments 147 spaced along the longitudinal axis X1 of the panel assembly 101. In one embodiment, a respective one of the shunt band conductors 436, 437, or 438 is disposed in each shunt band compartment 147 and is configured to be electrically connected to a respective pole of at least one power switch of the respective pair of power switches 310 a310 a, 310 b. In one embodiment, to enable electrical connection of the shunt ribbon conductors 436, 437, or 438 to both the corresponding main bus conductor 136, 137, 138 and the pole of the corresponding circuit breakers 310 a310 a, 310 b, each shunt ribbon compartment 147 includes a corresponding mounting base shunt ribbon opening 148 defined, dimensioned, and arranged therethrough to enable functional placement of a corresponding one of the corresponding shunt ribbon connectors 436, 437, or 438 therethrough. The divider walls 149 also separate the poles of adjacent circuit breakers 310a310a, 310b and thereby prevent inadvertent bridging between different electrical potential shunt band conductors 436, 437 or 438.In some embodiments, to isolate the portions of the shunt ribbon conductors 436, 437, 438 disposed in the shunt ribbon compartments 147 that are not to be operatively connected to a pole of a power switch 310 a310 a, 310 b, a shunt ribbon cover 161 is operatively disposed between the shunt ribbon conductors and at least one of the power switches 310 a310 a, 310 b. A respective shunt band cover aperture 150 is defined therethrough and is sized and arranged to allow for functional placement of a portion of a respective one of the respective shunt band conductors 436, 437 or 438 and thereby make it easily connectable to a respective pole of a circuit breaker 310a310a, 310b. In an embodiment, the branch tape cover 161 is formed from a plate of an insulating material such as Noryl.In one embodiment, the circuit breaker mounting base 144 is arranged and configured to functionally support at least one pair of conventional circuit breakers 310 a310 a, 310 bin a spaced apart orientation in the housing interior portion 112. When operatively supported on the insulating base 144, the power switches 310 a, 310 bare arranged to define a space 401 therebetween, the space 401 having a second longitudinal axis X 2 extending substantially parallel to the first longitudinal axis X 1.In the embodiments illustrated in FIGS. 1-4, the circuit breakers 310 a, 310 bare conventional three-pole circuit breakers, each having multiple poles, for example, a first, second and third pole 321 a, 322 a, 323 aof a three-pole circuit breaker 310 aand a first, second and third pole 321 b, 322 b, 323 bof a three-pole circuit breaker 310 b. As shown, each one of the poles 321 a, 322 a, 323 aof the circuit breaker 310 has a corresponding opposite one of the poles 321 b, 322 b, 323 bon the opposite circuit breaker 310 b. The first circuit breaker 310a of the pair of circuit breakers 310a, 310b includes a housing 330a having a first end surface 331a defining at least one outlet opening, such as an outlet opening 341a, thereon. The second circuit breaker 310 bof the pair of circuit breakers 310 a, 310 bincludes a housing 330 bhaving a second end surface 331 bdefining at least one second outlet opening, such as an outlet opening 341 b, thereon.The outlet openings 341 a, 341 bare arranged and configured to emit ionized gases, shown as arrow 65, from the interior of the circuit breakers 310 a, 310 b,for example in the event of an electrical fault. In the embodiment illustrated in FIG. 4, the first end face 331a defines a plurality of outlet ports, such as exit ports 341a, 342a, 343a thereon, for their respective poles 321a, 322a, 323a; and the second end face 331b defines a plurality of outlet ports, such as exit ports 341b, 342b, 343b thereon, for their respective poles 321b, 322b, 323b. The discharge openings 341 a, 342 a, 343 a, 341 b, 342 b, 343 bare arranged and configured to discharge ionized gases 65 from the interior of the circuit breakers.The insulating barrier 900 is sized and configured to be operatively disposed in the space 401 and to define a first space region 931 having a first cross-sectional area therein and having a third longitudinal axis X 3. The first clearance region 931 is disposed immediately adjacent the first circuit breaker 310 aof the pair of circuit breakers 310 a, 310 band in flow communication with the exhaust outlet ports 341A, 342A, 343A of the first circuit breaker 310 a. Additionally, the insulating barrier 900 is further dimensioned and configured to be operatively disposed in the gap 401 to define a second clearance region 932 having a second cross-sectional area therein proximate the second power switch 310 bof the pair of power switches 310 a, 310 band having a fourth longitudinal axis X 4 therein. The second clearance area 932 is disposed immediately adjacent the second circuit breaker 310 bof the pair of circuit breakers 310 a, 310 band is disposed in flow communication with the exhaust outlet ports 341 b, 342 b, 343 bof the second circuit breaker 310 a. In one embodiment, the third and fourth longitudinal axes X 3, X 4 extend substantially parallel to the first longitudinal axis X 1. For example, in one embodiment, the third and fourth longitudinal axes X 3, X 4 of the first and second clearance regions 931, 932 are arranged to extend between the first end 101 aand the opposing second end 101 bof the panel assembly 101.Further, the insulating barrier 900 is arranged to be operatively connected in fluid communication with the exhaust outlet ports 341 a, 342 a, 343 a, 341 a, 342 bof the power switch 310 a, 310 b. For example, the insulating barrier 900 may be disposed immediately at the first and second end surfaces 331 a, 331 bof the first and second power switches 310 a, 310 b.In an exemplary embodiment, as shown in FIGS. 4, 8, and 9, the insulating barrier 900 may be formed with a first cantilevered wall member 911 defining first and second opposing wall surface portions 912, 913 having a first basal end 911 aand a first distal end 911 b.For example, in one embodiment, as shown in FIG. 4, the first wall surface portion 912 of the first cantilevered wall member 911 is disposed opposite the circuit breaker face 311 aand in operable flow communication with corresponding exhaust outlet openings 341 a, 342 a, 343 a. Similarly, the second wall surface portion 913 of the first cantilevered wall member 911 is disposed opposite the second circuit breaker end surface 311 band in operable flow communication with corresponding exhaust outlet ports 341B, 342B, 343B. The first cantilevered wall member 911 is further configured to be movable in response to an increase in the pressure in the respective first and second clearance portions 931, 932 resulting from the presence of ionized gases 65 as they exit at least one power switch of the pair of power switches 310 a, 310 b. In addition, the first cantilevered wall member 911 is configured for deflection in a direction away from the ionized gases 65 as they exit at least one power switch 310 a, 310 bof the pair of power switches 310 a, 310 b, resulting in an increase in the cross-sectional area of the corresponding first and second clearance portions 931, 932. In one embodiment, and as shown in FIGS. 5 and 7, an increase in the cross-sectional area of one of the respective first and second clearance portions 931, 932 results in a decrease in the other of the first and second clearance portions 931, 932.For example, in one embodiment, as shown in FIGS. 5 and 8, the first cantilevered wall member 911 includes at least one first flexible cross member 951, such as at least one pleat or pleat disposed thereon. In further embodiments, the flexible cross member 951 may comprise a resilient member. In still further embodiments, the at least one first flexible cross member 951 may include a plurality of fold lines arranged to enable an insulating barrier function as described herein.Referring to FIG. 5, the first flexible cross member 951 is arranged to deflect in a first direction away from ionized gases 65 exiting at least one power switch of the pair of power switches 310a, 310b, thereby allowing first deflection of the first cantilevered wall member 911 in the direction away from ionized gases 65 exiting at least one power switch of the pair of power switches 310a, 310b, thereby increasing the cross-sectional area of the corresponding first and second clearance portions 931, 932. Additionally, in further embodiments, the first flexible cross member 951 is further configured to subsequently deflect in a second direction, thereby allowing a second deflection in the second direction of the first cantilevered wall member 911 in response to a pressure reduction in the corresponding first or second clearance portion 931, 932 when the leaked ionized gases 65 have spread. In one embodiment, the second direction is opposite the first direction.In one embodiment, the first basal end 911 aof the first cantilever wall member 911 is disposed immediately at the grounded switchboard 119 a, and the first distal end 911 bis disposed immediately at the insulating base 144.For example, in one embodiment, the insulating barrier 900 may additionally include at least a first outer wall member 941 and a second outer wall member 942. Each of the first and second outer wall members 941, 942 is disposed substantially perpendicular to the cantilevered wall member 911. In an embodiment, the first outer wall element 941 is connected to the first basal end 911 aof the cantilevered wall element 911 and the second outer wall element 942 is connected to the first distal end 911 bof the cantilevered wall element 911. In some embodiments, the second outer wall member 942 includes support means 935 (not shown), such as slots defined therethrough. For example, the support means (not shown) may be configured to cooperate with the divider walls 149 to position the insulative barrier 900 and prevent undesired movement.In further embodiments, the insulating barrier 900 may alternatively be additionally formed with a second cantilevered wall member 921 defining two opposing wall surface portions 922, 923 having a second basal end 921 aand a second distal end 921 b. The first and second cantilever wall members 911, 921 are arranged to overlap at least a portion of the respective distal ends 911 band 921 b. In one embodiment, each of the first and second cantilevered wall members 911, 921 is disposed immediately and substantially opposite the end faces 331 a, 331B of the first and second circuit breakers and is fluidly connected to at least one of the exhaust outlet ports 341 a, 342 a, 343 a, 341 b, 342 b, 343 bof at least one circuit breaker 310 a, 310 b.For example, in one embodiment, as shown in FIGS. 6 and 9, the first wall surface portion 912 of the first cantilevered wall member 911 is disposed opposite the first circuit breaker end surface 331 aand is disposed in operative flow communication with corresponding exhaust outlet openings 341 a, 342 a, 343 a. Likewise, the first wall surface portion 912 of the second cantilevered wall element 921 is additionally disposed opposite the end surface 331 aof the first circuit breaker and is disposed in operative flow communication with corresponding exhaust outlet openings 341 a, 342 a, 343 a. Each of the first and second cantilevered wall members 911, 921 is further configured to be movable in response to an increase in pressure resulting from the presence of ionized gases 65 as they exit the circuit breaker 310 a. For example, each of the first and second cantilevered wall members 911, 921 may be further arranged to allow a first deflection away from the ionized gases 65 from at least one power switch of the power switches 310 a, 310 bto thereby increase the cross-sectional area of the corresponding first and second clearance portions 931, 932. In one embodiment, the increase in cross-sectional area of one of the respective first and second clearance portions 931, 932 results in a decrease in the other of the first and second clearance portions 931, 932.For example, in one embodiment, each of the first and second cantilevered wall members 911, 921 is arranged to cooperatively allow a first deflection in a first direction away from the ionized gases 65 exiting the first power switch 310 aof the pair of power switches 310 a, 310 b, thereby resulting in an increase in the cross-sectional area of the first clearance portion.Additionally, in further embodiments, in one embodiment, each of the first and second cantilevered wall members 911, 921 may be further configured to subsequently allow a second deflection in the second direction of the first cantilevered wall member 911 in response to a pressure reduction in the corresponding first or second clearance portion 931, 932 when the leaked ionized gases 65 have spread. In one embodiment, the second direction is opposite the first direction.In one embodiment, the first basal end 911 aof the first cantilevered wall member 911 is disposed directly at the panel intermediate plate 119 aand the second basal end 921 aof the second cantilevered wall member 921 is disposed directly at the insulating base.For example, in such an embodiment, the insulating barrier 900 may additionally include at least one of the first outer wall member 941 and the second outer wall member 942. Each of the first and second outer wall members 941, 942 may be disposed substantially perpendicular to the first and second cantilevered wall members 911, 912. In an embodiment, the first outer wall element 941 is connected to the first basal end 911 aof the cantilevered wall element 911 and the second outer wall element 942 is connected to the first basal end 912 aof the second cantilevered wall element 912. In some embodiments, the second outer wall member 942 additionally includes support means 935 (not shown), such as slots defined therethrough. For example, the support means 935 (not shown) may be configured to cooperate with the divider walls 119 to position the insulative barrier 900 and prevent its undesired movement.In an exemplary embodiment, the second wall surface portion 913 of the first cantilevered wall member 911 is disposed opposite the circuit breaker face 331 band is disposed in operative flow communication with corresponding exhaust outlet openings 341 b, 342 b, 342 b. Likewise, the second wall surface section 923 of the second cantilevered wall element 321 is additionally arranged opposite the end surface 331 bof the second circuit breaker and is arranged in flow communication with corresponding exhaust outlet openings 341 b, 342 b, 342 b. Each of the first and second cantilevered wall members 911, 921 is further configured to be movable in response to an increase in pressure resulting from the presence of ionized gases 65 as they exit the circuit breaker 310 a. In addition, each of the first and second cantilevered wall members 911, 921 is further configured to deflect in a direction away from the ionized gases 65 as they exit the power switch 310 a, resulting in an increase in the cross-sectional area of the second clearance portion 932.In such an embodiment, as shown in FIGS. 4 and 9, the first basal end 911 aof the first cantilever wall member 911 is disposed directly at the intermediate plate 119 aof the switchboard, and the second basal end 912 aof the second cantilever wall member 912 is disposed directly at the insulating base 144.For example, in one embodiment, the insulating barrier 200 may additionally include at least one of a first outer wall member 941 and a second outer wall member 942. Each of the first and second outer wall members 941, 942 may be disposed substantially perpendicular to the cantilevered wall member 911. For example, in one embodiment, the first and second outer wall elements 941, 942 are arranged substantially parallel to one another. In an exemplary embodiment, the first outer wall member 941 is hingedly connected to the first basal end 911 aof the cantilevered wall member 911 and the second outer wall member 942 is hingedly connected to the second basal end 921 aof the cantilevered wall member 921.In some embodiments, the second outer wall member 942 additionally includes one or more support features 935 (not shown), such as a plurality of slots defined therethrough. For example, the support means (not shown) may be configured to cooperate with the divider walls 149 to position the insulative barrier 900 and prevent undesired movement.In an embodiment, the first basal end 911 aof the first cantilevered wall element 911 is disposed proximate the panel intermediate plate 119 aand the second basal end 921 aof the second cantilevered wall element 921 is disposed proximate the insulating base 144, wherein the first and second distal ends 911 b, 921 bare at least partially overlapping and substantially parallel to each other. In further embodiments, the insulating barrier 120 may be formed with any number of cantilevered wall elements and have any number of cross-sectional arrangements operatively disposed in the gap 410 and defining at least the first and second clearance regions 931, 932 therebetween, and that enable the insulating barrier 900 to function as described herein.The insulating barrier 900 is configured to deflect in response to heat and pressure in ionized exhaust gases exiting the first and second collection spaces 931, 932, thereby increasing the size of one of the clearance areas 931, 932 and, in some embodiments, simultaneously decreasing the size of the other clearance area 931, 932. Ionized exhaust gases 65 are thereby directed away from both the live and grounded conductive portions in the circuit board 101. Once they have leaked into the one of the first and second clearance areas 931, 932, the exhaust gases 65 circulate in the corresponding clearance areas 931, 932 and are guided along one of the third and fourth longitudinal axes X 3, X 4 to displace them away from the high pressure and toward the low pressure portions of the concerned clearance area 931, 932. Contact of the ionized exhaust gases 65 with a live or grounded conductor is thereby prevented.In some embodiments, the insulating barrier 900 may be made of any suitable electrically insulating material, such as a flame resistant flexible polypropylene plate. In other embodiments, the insulating barrier 900 may be made of any suitable conductive insulating material.In one embodiment, the insulating barrier 900 may be advantageously formed from a one-piece plate of a suitable material. For example, such a one-piece panel may be folded or otherwise bent to place the insulating barrier 900. To enable the formation of the barrier 900 from a one-piece sheet, the sheet may have creases or perforations formed thereon to guide the folding of the film to form the barrier 900.In still other embodiments, multiple insulating plates may be used to form the insulating barrier 900, which has any number of configurations that enable the insulating barrier to function as described herein.In some embodiments, one or more support means (not shown), such as slots, are provided on the insulating barrier 900. For example, the support means may be configured to cooperate with the divider walls 149 to prevent undesired movement of the insulating barrier 120. In still further embodiments, as shown in FIG. 5, the grounded front of the panel 119 amay be operatively arranged to provide a holding force with respect to the insulating barrier 900 to maintain the insulating barrier 900 in the operative position within the gap 401.The order of execution or execution of the operations in the embodiments of the invention illustrated and described herein is not important unless otherwise indicated. That is, the operations may be performed in any order unless otherwise specified, and embodiments of the invention may include additional or fewer operations than those disclosed herein. For example, it is contemplated that execution or performance of a particular operation, before, simultaneously, or after another operation is within the scope of aspects of the invention.When introducing elements from aspects of the invention of the present invention or its embodiments, the articles "a, an", "the", and "said, said" are intended to mean that one or more of the elements may be present. The terms "comprising", "containing" and "having" are intended to be inclusive and have the meaning that additional elements other than the listed elements may be present.This specification uses examples to disclose the invention, including the best mode thereof, and also to enable any person skilled in the art to make and use the invention. Such further examples are intended to be included within the scope of the invention, provided they have structural elements that do not differ from the wording of the claims, or if they include equivalent structural elements with insubstantial changes from the wording of the claims.An electrical switching device for accommodating a pair of opposing circuit breakers is described, each circuit breaker of the pair of opposing circuit breakers including an opposing face having an exhaust outlet disposed therein. The electrical switching device includes a switchboard for operatively supporting the pair of opposing power switches to define a space therebetween and an insulative barrier to be operatively disposed within the space. The insulating barrier includes a first cantilevered wall member that is positionable to define a first clearance area having a first cross-sectional area and a second clearance area having a second cross-sectional area. The insulating barrier functions to deflect in a first direction to thereby increase one of the first and second cross-sectional areas in response to ionized gases exiting a power switch of the pair of power switches.

Claims

An electrical switching device comprising a pair of opposing circuit breakers (310a, 310b), each circuit breaker (310a, 310b) of said pair of opposing circuit breakers (310a, 310b) including an opposing face (331a, 311b) having an exhaust outlet disposed therein, said switching device comprising: a circuit board configured to functionally support said pair of opposing circuit breakers (310a, 310b) to define a space (401) therebetween; an insulating barrier (900) configured for functional placement in said space (401) and having a first cantilevered wall member (911) disposed to define a first clearance region (931) having a first cross-sectional area and a second clearance region (932) having a second cross-sectional area; and wherein the insulating barrier (900) functions to deflect in a first direction to thereby increase a first or second cross-sectional area in response to an ionized gases (65) exiting a power switch (310a, 310b) of the pair of power switches (310a, 310b).The electrical switching device of claim 1, wherein the insulating barrier (900) further functions to simultaneously decrease the other of the first and second cross-sectional areas in response to the ionized gases (65) exiting a power switch (310a, 310b) of the pair of power switches (310a, 310b).Electrical switching device according to claim 1, wherein the insulating barrier (900) further comprises holding means (935) configured to hold the insulating barrier (900) in the intermediate space (401) in the operating position.The electrical switching device of claim 1, wherein the insulating barrier (900) further comprises a first outer wall member (941) and a second outer wall member (942); and wherein the first cantilevered wall member (911) is substantially perpendicularly connected to and interposed between the first and second outer wall members (941, 942).The electrical switching device of claim 1, wherein the first cantilevered wall member (911) further comprises a first flexible cross member (951) configured to deflect in the first direction in response to an egress of ionized gases (65) from a power switch (310a, 310b) of the pair of power switches (310a, 310b).The electrical switching device of claim 5, wherein the flexible cross member is one of a pleat, a buckle, or a resilient member.The electrical switching device of claim 5, wherein the first flexible cross member (951) is further configured to subsequently allow a second deflection in a second direction of the first cantilevered wall member (311).The electrical switching device of claim 1, wherein the insulating barrier (900) further comprises a second cantilevered wall element (921) that cooperates with the first cantilevered wall element (911) to define the first clearance area (931) and the second clearance area (932).The electrical switching device of claim 8, wherein the first and second cantilevered wall members (911, 921) are each configured to cooperatively deflect in a first direction to thereby increase one of the first and second cross-sectional areas in response to the ionized gases (65) exiting a circuit breaker (310a, 310b) of the pair of circuit breakers (310a, 310b).An electrical protection system having a pair of circuit breakers (310a, 310b) comprising: a housing (111) for receiving the pair of circuit breakers (310a, 310b); the housing (111) being configured to functionally support the pair of circuit breakers (310a, 310b) to define a space (401) therebetween; an insulating barrier (900) configured for functional placement within the space (401) comprising a first cantilevered wall member (911) disposed to define a first space region (931) having a first cross-sectional area and a second space region (932) having a second cross-sectional area; wherein the insulating barrier (900) functions to deflect in a first direction to thereby increase a first or second cross-sectional area in response to an ionized gases (65) exiting a power switch (310a, 310b) of the pair of power switches (310a, 310b).

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