Fire Enclosure

Abstract

An apparatus for enclosure of a direct current connection of a photovoltaic solar panel is provided, the apparatus comprising a housing having at least two parts configured to form a chamber for enclosing a pair of mating DC connectors with an air gap when coupled together, the housing comprising at least one support structure for positioning the DC connectors in a central portion of the chamber.

Description

[Technical field]

[0001] The following relates to methods, devices and systems relating to DC connectors. [Background technology]

[0002] The deployment of photovoltaic (PV) systems has experienced rapid growth in recent years due to the high demand for renewable energy and the rapid cost reduction of the technology.

[0003] Photovoltaic modules convert solar energy into DC power, which can be used directly or converted to AC for downstream consumption. Often, multiple PV modules are electrically connected in series or parallel via DC connectors (direct current connectors). For example, MC4 connectors are single-contact electrical connectors commonly used to connect solar panels.

[0004] Arcing is a potential problem in DC connectors. The term "arcing" refers to the flow of electrical current through a hot plasma caused by a potential difference across the air gap. Many research projects have concluded that the risk of PV fires is due to improperly manufactured or poorly connected connectors, such as connecting connectors from different manufacturers or improperly installing connectors. As connections deteriorate, the risk of arcing increases over time. High temperatures from arcing can cause fires near the DC connector.

[0005] DC connectors used in solar PV systems are therefore designed to minimise the risk of arcing, through rigorous conductor design and the associated ingress protection (IP rating) against the ingress of dust and water (typically IP68 rating or lower).

[0006] Several mechanisms have been developed to minimize the risk of fire due to arcing.

[0007] As a first example, several industry regulatory provisions have been introduced in various jurisdictions to minimize the risk of fire. It is common in the industry to promote robust installation training programs and to prohibit the use of incompatible connectors from different manufacturers. Neither approach has eradicated the problem, as evidence of PV fires caused by DC arcing continues to occur. As a result, certain regions have mandated arc fault detection for photovoltaic systems, and all PV systems with a maximum voltage above 80 volts are protected by DC arc fault circuit interrupters. This measure results in false and unnecessary shutdowns and does not necessarily detect all faults, such as slowly developing arcing.

[0008] Another approach is to enclose the DC connector in a protective enclosure, which, in the event of a DC arcing fault, can limit the spread of fire to the connector itself and prevent further damage to the surrounding elements.

[0009] For example, in Patent Document 1 (China Utility Model Specification No. 201699384), Liu and Wang proposed a solution of creating a shell in which the DC connector is placed and filling the shell with fine sand to prevent the spread of fire.

[0010] Similarly, in Patent Document 2 (CN 105811163), Cai et al. proposed to place a DC connector in a receiving cavity and seal it with a fire-resistant filler.

[0011] However, these solutions to encapsulate DC connectors can have adverse effects in the event of a thermal event, where the connector integrity is compromised due to material incompatibility or increased operating temperatures. As a specific example, some fillers can adversely affect the DC connector materials and accelerate their degradation. The laborious process of encapsulation is also not practical in real-world installations.

[0012] Other approaches have been considered to provide special cavity shapes to minimize arcing. For example, in Patent Document 3 (China Utility Model No. 208738495), Jiang et al. placed a DC connector in an open-ended ceramic protective tube and fixed the cable with metal pins that extend through both ends of the tube. Although the tube may be able to withstand arcing temperatures, it is questionable how a fire can be contained inside the open-ended tube. Furthermore, the open-ended tube may provide a water passage into the connector, increasing the risk of arcing.

[0013] As an example of a different approach, new cable connection mechanisms have been developed. For example, in Patent Document 4 (China Utility Model No. 209747847), Liu and Wen devised a new cable connection method that utilizes a fire-resistant heat-shrinkable sleeve to protect the cable and crimps two cables together and secures them with a pin. In Patent Document 5 (JP 2020-137367 A), Miyamoto et al. propose a similar design concept that uses heat-resistant tape to prevent the spread of fire. Both solutions differ from the typical standard DC connectors currently attached to solar panels, a feature that has contributed to the widespread acceptance of solar installations.

[0014] While all of these solutions attempt to solve the same problem by containing the spread of fire, these inventions increase the risk of arcing in the first place by providing insufficient airflow to the connector and / or by allowing water to easily accumulate around the connector. The problem is exacerbated by increased operating temperatures and the risk of water ingress, increasing the likelihood of failure leading to arcing. [Prior art documents] [Patent documents]

[0015] [Patent Document 1] China Utility Model No. 201699384 [Patent Document 2] China Patent Application Publication No. 105811163 [Patent Document 3] China Utility Model No. 208738495 [Patent Document 4] China Utility Model No. 209747847 [Patent Document 5] JP 2020-137367 A Summary of the Invention

[0016] The present invention is defined by the accompanying independent claims, with particular more particular aspects being defined by the dependent claims.

[0017] According to a first aspect, there is provided an apparatus for enclosure of a DC connection of a photovoltaic solar panel, the apparatus comprising a housing having at least two parts configured to form a chamber for enclosing a pair of mating DC connectors with an air gap when coupled together, the housing comprising at least one support structure for positioning the DC connectors in a central portion of the chamber.

[0018] The at least one support structure may be configured to contact at least one cable connected to one of the DC connectors to suspend the DC connectors in a central region of the chamber.

[0019] The at least one support structure may be configured to restrict lateral movement of the DC connector in at least one direction.

[0020] The housing may include an inner surface facing the chamber, the inner surface being at least partially coated with an expandable material.

[0021] The device may include at least one first port for expelling water from the housing.

[0022] The apparatus may include at least one second port for the flow of air into and out of the chamber.

[0023] The at least one first port and / or the at least one second port may provide access points for a labyrinth of passageways for water egress, air ingress, and / or air egress.

[0024] The at least one first port and / or the at least one second port may be located at a distal end of at least a portion of the housing.

[0025] The at least one first port and / or the at least one second port may comprise an interior surface at least partially coated with an expandable material.

[0026] The housing may include upper and lower portions that engage with each other to surround the DC connector.

[0027] The housing may include a tubular portion having two open ends and two end caps configured to cover the open ends of the tubular portion.

[0028] The housing may comprise a dielectric material.

[0029] The housing may have at least one exterior surface configured to direct water toward an edge of the housing.

[0030] According to a second aspect, there is provided an assembly comprising any of the devices of the first aspect, the assembly comprising an outer housing configured to receive the device within an internal cavity defined by an inner surface of the outer housing.

[0031] The outer housing may be configured to cover at least one port on the device.

[0032] The inner surface of the outer housing may be at least partially coated with an expandable material.

[0033] The outer housing may include a bracket configured for attachment to a support structure.

[0034] The assembly may further comprise at least one split grommet configured to be disposed within the outer housing for receiving a DC cable connected to at least one of the DC connectors.

[0035] The outer housing may be configured to hold the at least two parts of the housing together.

[0036] The outer housing may have at least one exterior surface configured to direct water to an edge of the outer housing.

[0037] The assembly may further comprise a DC connector having a rating established by a manufacturer of the DC connector, and the size of the gap may be selected to enable the DC connector to operate at or below the rating.

[0038] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claims, nor is it intended to be used to limit the scope of the claimed subject matter. Nor is the claimed subject matter limited to implementations that solve some or all of the disadvantages discussed in the Background Description. [Brief description of the drawings]

[0039] The embodiments will now be described in more detail, by way of example only, with reference to the following embodiments and the accompanying drawings.

[0040] [Figure 1A] A diagram of a first configuration example is shown. [Figure 1B] A diagram of a first configuration example is shown. [Figure 1C] A diagram of a first configuration example is shown. [Figure 2A] A diagram of a second configuration example is shown. [Figure 2B] A diagram of a second configuration example is shown. [Figure 2C] A diagram of a second configuration example is shown. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0041] The following configuration aims to address at least one of the above-mentioned problems. In particular, the following configuration relates to providing an enclosure for containing a fire resulting from an arc discharge at a DC connector and preventing the resulting spread of the fire to surrounding materials. This applies in particular to an enclosure for suppressing an arc discharge in a photovoltaic power generation system and preventing the spread of the fire to, for example, a roof-like element or an adjacent photovoltaic power generation system. The system disclosed in this embodiment also aims to allow the DC connector to operate under normal operating conditions without increasing the risk of arc discharge.

[0042] These challenges may be addressed by an apparatus that encloses mating DC connectors in a fire-resistant enclosure while maintaining sufficient air gap around the DC connectors, as described further below. The apparatus may be provided with vent openings to facilitate air flow to keep the connectors below a maximum operating temperature defined by the manufacturer. Such an enclosure may help prevent the spread of fire from the inside out, inhibit water ingress into the enclosed space, and / or allow water to drain if moisture accumulates within the enclosure.

[0043] The enclosure provided in this embodiment is described with respect to an inner housing, as further shown below. In addition to the inner housing, an outer housing is disclosed below that may provide further technical advantages when assembled with the inner housing. The inner and outer housings are generally described before more specific examples are described in connection with Figures 1A-2C.

[0044] Generally, hereinafter, an inner housing is disclosed that defines an air chamber (cavity) in which the mating DC connectors (a pair of DC connectors that are mated with each other) can be placed. The defined chamber can surround the mating DC connectors. In other words, the defined chamber can surround the mating DC connectors simultaneously on all sides of the DC connectors. This means that there are no open ends of the inner housing.

[0045] In the case where at least one support member is provided as a support structure proximal to the DC connector (see below), the gap may be at least x millimeters around the bar of the mating DC connector, where x is determined based on the amount of heat expected to be output from the DC connector during operation and / or the number of vents (ports) provided in the inner housing. In other words, in some configurations, no part of the inner housing is within x millimeters of the mating DC connector. In other configurations, the part of the inner housing within x millimeters of the mating DC connector may be at least one support member for positioning the DC connector in a central region of the chamber and / or for restricting lateral movement of the DC connector within the chamber. In a particular example, x may be 5 millimeters.

[0046] The inner housing may be provided with at least one support member that helps position the mating DC connector in a central region of the chamber (especially in a longitudinal direction within the chamber). The at least one support member may restrain lateral movement of the DC connector within the chamber. The at least one support member may assist in positioning the mating DC connector by contacting at least one of the cables associated with the mating DC connector. The at least one support member may be located at a distal end of the housing (i.e., away from the central region). The at least one support member may be located proximal to the central region. If there are multiple support members, they may be located both proximal and distal to the central region.

[0047] The inner housing is configured such that there is at least one port for fluid flow. The port may be formed as a result of the configuration of the edges of the connecting portion proximal to where the portions of the inner housing engage. Additionally or alternatively, the port may be configured as a hole or channel extending through the inner housing.

[0048] These ports may allow water to exit the inner housing (in the event of water ingress) or provide ventilation to aid in heat dissipation via airflow through the ports. The ports may have an inner surface through which fluids flow in and out of the inner housing, the inner surface being at least partially coated with an intumescent material. Under heating (e.g., if there is a fire in the enclosure), the intumescent material may expand to plug the port, thereby restricting airflow and thus aiding in fire extinguishing. For a similar effect, an area of ​​the inner housing proximal to the port may be at least partially coated with an intumescent material.

[0049] The port may be defined by a multi-part connection geometry (e.g., a port is formed where separate parts of the inner housing meet) and / or by holes located in the parts themselves. The port may be located within the inner housing at at least one distal end. In other words, if the mating DC connector is located in a central region of the chamber, the port may be located relatively far from this central region.

[0050] The inner housing may be formed of at least one material for inhibiting the spread of fire. For example, the inner housing may be made of at least one material capable of withstanding high temperatures resulting from a fire in the enclosure and corresponding thermal shock. In other words, the material of the inner housing may be selected to ensure that the inner housing is not prone to cracking after thermal shock from a fire in the enclosure. As used herein, this property of not burning when exposed to such fire shall be referred to as fire resistant, non-combustible, etc. This is further described below in connection with ceramic materials.

[0051] The inner housing may be provided from a dielectric material to minimize the possibility of continuing arcing through the inner housing in the event that the connector body burns off.

[0052] Below, an outer housing that covers at least a portion of the inner housing is also described. In other words, the outer housing may have at least one inner surface that receives the outer surface of the inner housing. The outer housing can hold together at least two parts of the inner housing. This avoids the need for an additional connection mechanism between these parts of the inner housing (although in some cases, an additional connection mechanism may be provided).

[0053] The outer housing may be configured to cover at least the ports of the inner housing to prevent water ingress and flame escape.

[0054] The outer housing may include ports for similar purposes as the ports on the inner housing. The ports on the outer housing may not be aligned with the ports on the inner housing. Having ports that are not aligned with one another creates a labyrinth of paths for fluid ingress and / or egress and helps to limit water ingress and flame egress. The ports on the inner housing and the ports on the outer housing may be configured to maintain the temperature surrounding the mating DC connectors within the manufacturer's ratings for those DC connectors.

[0055] At least a portion of the interior surface of at least one of the inner and outer housings may be coated with an intumescent material that may be selected to expand at flame temperatures that may be caused by arcing, thereby assisting in extinguishing the fire and shutting off the port and limiting the risk of flame escape in the event of arcing.

[0056] The outer housing may further include a sealing device, such as a gasket or grommet, that helps to inhibit water ingress into the outer housing where the DC cable of the mating DC connector enters the outer housing and to prevent flame escape.

[0057] 1A-2C illustrate particular implementations in which the techniques described herein may be implemented.

[0058] Figures 1A-1C show various views of the same embodiment of the device and assembly, with Figure 1B showing an exploded view of the assembly and Figure 1C showing a perspective view of the assembly.

[0059] 1A-1C show that a first cable 9A and a second cable 9B are connected to each other via corresponding DC connectors 8A, 8B. The DC connectors 8A, 8B are surrounded by an air gap. This air gap may be at least 5 mm (5 mm or more). The first cable 9A and the second cable 9B are supported at their respective ends by inner housings 1, 2 that surround the DC connectors 8A, 8B. In this embodiment, the inner housings 1, 2 comprise two separate parts for ease of assembly (as described below). The first cable 9A and the second cable 9B are also supported at their respective ends by additional supports 3A, 3B that are connected to the inner housings 1, 2 (e.g., the lower part 2).

[0060] Furthermore, the first cable 9A and the second cable 9B are supported in a central position by corresponding retention devices 7A, 7B (e.g., grommets or gaskets) in the outer housing 5, 6 that surrounds (contains) the inner housing 1, 2. The retention devices 7A, 7B may also provide a sealing function by inhibiting water ingress and flame escape at the location where the first cable 9A and the second cable 9B enter the outer housing. The inner housing also includes holes 4A, 4B that allow water egress and air ingress. Note that not all of these holes 4A, 4B are shown. Furthermore, the holes 4A, 4B may be configured to extend in a complex manner (maze-like) to the outer surface of the outer housing 5, 6 to inhibit water ingress and flame escape. The outer housing 5, 6 may be attached to a bracket 17 for fixing to a roof-like structure 11 (or any structure 11 for a PV system) via fasteners 10. The structure 11 may for example be a plank of wood or a support rail which may be made of a metal such as steel or aluminium.

[0061] During assembly, the DC connectors 8A, 8B are connected together before being placed on either of the inner housing parts 1, 2. The other inner housing part 1, 2 is then connected to form a cavity containing the DC connectors 8A, 8B. The outer housing parts 5, 6 are connected together over the inner housings 1, 2 to completely surround (contain) the inner housings 1, 2. The end plates of the outer housings 5, 6 may be provided with at least one slot to allow the first cable 9A and the second cable 9B to slide into position when the outer housing parts 5, 6 are joined together. The outer housings 5, 6 are then attached to a structure 11 via a bracket 17 and fasteners 10. The bracket 17 may be integral with at least a portion of the outer housings 5, 6 or may be separate from the outer housings 5, 6.

[0062] Figures 2A-2C show another embodiment of an apparatus and assembly according to the techniques described herein, with Figure 2B showing an exploded view of the assembly and Figure 2C showing a perspective view of the assembly.

[0063] 1A-1C, which shows an inner housing 1,2 made of two parts, an upper part 1 and a lower part 2, Fig. 2 shows an embodiment with an inner housing having a tubular part 12 and two end caps 13. The end caps 13 serve to cover the ends of the tubular part 12 and thereby prevent flames from escaping from the ends of the tubular part 12.

[0064] 2A-2C show that a first cable 9A and a second cable 9B are connected to each other via corresponding DC connectors 8A, 8B. The DC connectors 8A, 8B are surrounded by an air gap. This air gap may be at least 5 mm (5 mm or more). The first cable 9A and the second cable 9B are supported at their respective ends by end caps 13A, 13B. The end caps 13A, 13B contact a part of the first cable 9A or the second cable 9B at their support parts (support structures) 14A, 14B, but do not surround the DC connectors 8A, 8B. A tubular part 12 (which may be made of a non-combustible / fire-resistant material) contacts both end caps 13A, 13B at their respective ends of the tubular shape. The tubular part 12 radially surrounds the DC connectors 8A, 8B in use.

[0065] Furthermore, the first cable 9A and the second cable 9B are supported in a central position by corresponding retention devices 7A, 7B (e.g., grommets or gaskets) in the outer housing 16 that surrounds the tubular portion 12 and the end caps 13A, 13B. The retention devices 7A, 7B may also function as sealing devices that help inhibit water ingress into the outer housing 16. The tubular portion 12 and / or the end caps 13A, 13B also include at least one hole 15 (or are configured to provide at least one exit port) that allows water to escape and air to enter. It is noted that not all of these holes 15 are shown. Furthermore, the holes (ports) 15 may be configured to extend in a labyrinth-like manner to the outer surface of the outer housing 16 to inhibit water ingress and flame escape. The outer housing 16 may be attached via fasteners 10 to brackets 17 for fastening to a roof-like structure 11 (or any structure 11 for a PV system). The structure 11 may be, for example, a wooden plank or a support rail which may be made of a metal such as steel or aluminum.

[0066] During assembly, at least one of the first cable 9A and the second cable 9B may be slid into the corresponding end cap 13A, 13B and passed through the tubular portion 12 such that the corresponding DC connector 8A, 8B emerges from the other end of the tubular portion 12. The DC connectors 8A, 8B may then be mated (connected) to one another before being repositioned into the central interior region of the tubular portion 12. The remaining end cap 13A, 13B may then be slid over the remaining one of the first cable 9A and the second cable 9B and attached to the other end of the tubular portion 12.

[0067] The inner housing (tubular portion 12 and end caps 13A, 13B) is then placed within the outer housing 16 such that the outer housing 16 partially surrounds the inner housing. The end plates of the outer housing 16 may include at least one slot to allow the first and second cables 9A, 9B to slide into place as they are inserted into the outer housing 16. The outer housing 16 is then attached to the structure 11 via bracket 17 and fasteners 10. The bracket 17 may be integral with at least a portion of the outer housing 16 or may be separate from the outer housing 16.

[0068] The following describes features (configurations) that apply to both of the above-mentioned embodiments. The features described below are also applicable to other configurations of the inner housing and the outer housing (e.g., rectangular parallelepiped configurations). In other words, the following disclosure is not limited to these two embodiments, but is merely a description using a specific example.

[0069] In either of the two embodiments, support of the cable at both ends of the DC connector prevents contact between the connector itself and the material of the enclosure. This support also acts as a cable restraint to ensure the connector is held in a central position for maximum fire protection and ventilation. Additionally, this arrangement reduces the risk of contact with incompatible materials that could impair the life of the connector. The DC connector may be an MC4 connector (multiple contact), or similar.

[0070] Both the embodiments of Figures 1 and 2 provide support features (support structures) 3, 14 that may be integral parts of the inner housing. These support features 3, 14 are separate from the support that may be provided by the outer housing through clearance for the cables 9A, 9B (including any grommets). The support features 3, 14 may be located in a position that ensures a clearance of 5 mm or more (at least 5 mm) around the DC connector. The support features 3, 14 may be configured to prevent lateral movement of the connector within the inner housing. For example, the support features 3 may be manufactured to nearly abut (close to) the edges of the DC connectors 8A, 8B.

[0071] The inner housing (1, 2, 12, 13) may be made of a ceramic material that can withstand high temperatures and the corresponding thermal shock. This objective may be achieved with a wall thickness of 10 mm. The ceramic material may be selected so that the device does not crack after thermal shock. The selected ceramic material has dielectric properties that prevent circuit continuity in the event that arc damage destroys the connector and contacts the device.

[0072] The inner housing of Figures 1 and 2 above may be manufactured from materials such as alumina cement or calcium aluminate. More specifically, the inner housing of Figure 1 may be made by casting from a refractory material. Furthermore, the tubular portion 12 of Figures 2A-2C may be manufactured from a refractory material by extrusion, and the two end caps may be manufactured from a dense machinable ceramic by casting or machining. However, the manufacturing methods of the components are not limited thereto.

[0073] The inner housing may be configured to maintain a temperature below 105 degrees when 39 amps of current is flowing through the connector and ambient conditions are 85 degrees. This may be accomplished by a tradeoff between the air gap surrounding the DC connector and the number and size of vent and / or drain ports in the inner housing. In other words, the inner housing may be configured to maintain a temperature within the cavity below the rated maximum operating temperature of the DC connector at the rated current and ambient temperature of the DC connector.

[0074] At least one exterior surface of the inner and / or outer housing may be shaped to repel water and prevent water from entering the chamber (cavity) defined by the housing. This may be done, for example, as a result of contouring the at least one exterior surface to direct water incident on the at least one exterior surface to an edge of the at least one exterior surface. In this context, an edge is a location where water may leave the outer and / or inner housing under the influence of gravity.

[0075] Generally, the enclosure is provided with sufficient drainage holes (drain ports) 4, 15 to allow gravity to drain any moisture that may accumulate within the enclosure regardless of the orientation of the enclosure. The drainage holes 4, 15 may be radially positioned at the ends of the enclosure, farthest from the location where arcing is most likely to occur in the center of the cavity formed by the inner housing.

[0076] The outer housing 5, 6, 16 may hold all of the components of the inner housing together by forming an internal cavity that can accommodate the DC connectors 8A, 8B. The outer housing may overlap at least some of the drain and vent holes of the inner housing, creating a labyrinth of passageways that may allow water and air movement from within the enclosure to prevent flame escape while facilitating ventilation to ensure the DC connectors remain dry.

[0077] The outer housing described with respect to Figures 1A-1C can also be used as the outer housing in the system of Figures 2A-2C, and vice versa.

[0078] A coating of intumescent material (i.e., a material that expands to a larger volume when heated) may be applied to the inside surface of the outer housing to close the vent and drain holes in the event of arcing.

[0079] In both of the above two embodiments, the outer housing is provided with a number of retention devices 7. These retention devices 7 may prevent the cables from rubbing and provide a better seal around the cable entry than if no retention devices 7 were provided. These retention devices 7 may be made from Ethylene Propylene Diene Monomer (EPDM) rubber. These retention devices 7 (sealing gaskets) may be split gaskets that allow the cable to be inserted even if the cable already has a connector on its end.

[0080] The DC connectors 8A, 8B and cables 9A, 9B may be standard components commonly used in the photovoltaic (PV) industry. For example, in current specifications, the DC connectors 8A, 8B and cables 9A, 9B may have a maximum operating temperature in accordance with the required electrical standards (i.e., IEC 60512-5-1 and IEC 62852) and may be 4 mm 2 The maximum operating temperature for this DC cable is 105°C with a current load of 39 amps and an ambient temperature of 85°C. The actual connectors, cables, and configurations may be selected to comply with the particular electrical standards applicable to the installed system.

[0081] Above, some specific examples of how the present invention may be implemented are provided, with more general principles illustrated with respect to the specific embodiments of Figures 1A-2C. However, the present invention is not limited thereto. Below, a general disclosure of an inner housing, an outer housing, and an assembly including these two housing arrangements is provided, with the inner housing also referred to simply as "housing". The features described above in relation to the specific embodiments may also form part of the more general disclosure below.

[0082] In a first aspect, an apparatus for enclosure of a DC connection of a photovoltaic solar panel is provided, the apparatus comprising an inner housing having at least two parts that, when coupled together, form a chamber for surrounding a mating DC connector with an air gap.

[0083] The housing includes at least one support structure for locating a DC connector in a central portion of the chamber.

[0084] The at least one support structure is configured to contact at least one cable connected to one of the DC connectors to suspend the DC connector in the central region of the chamber. The at least one support structure is configured to restrict lateral movement of the DC connector in at least one direction. The at least one support structure may restrict lateral movement of the DC connector by contacting the at least one cable. Restricting movement of the DC connector helps to hold the DC connector within an air gap sufficient for the DC connector to operate at or below the manufacturer's rating. If the DC connector has different manufacturer's ratings, the most restrictive rating applies.

[0085] The housing includes an inner surface facing the chamber, which may be at least partially coated with an expandable material, which may be disposed near (proximal to) at least one port (described further below).

[0086] The apparatus may include at least one first port for draining water from the fire-resistant housing. The apparatus may include at least one second port for air flow into and out of the chamber. The at least one first port and / or the at least one second port may be provided by a mating arrangement of parts of the housing. The at least one first port and / or the at least one second port may be formed by a channel extending through the housing.

[0087] The at least one first port and / or the at least one second port may provide access points for a labyrinth of passageways for water egress, air ingress, and / or air egress. The at least one first port and / or the at least one second port may be disposed at a distal end of at least a portion of the housing. The at least one first port and / or the at least one second port may each comprise an inner surface, and at least one inner surface may be partially coated with an expandable material.

[0088] The housing may include upper and lower portions that mate (engage) with one another to surround the mating DC connector, for example as described with reference to Figures 1A-1C.

[0089] The housing may comprise a tubular portion having two open ends and two end caps configured to cover the open ends of the tubular portion, for example as described with reference to Figures 2A-2C.

[0090] The housing may include a dielectric material. The dielectric material may be a ceramic material. The dielectric material may be selected to be less susceptible to cracking due to thermal shock from a fire occurring within the enclosure. The use of a dielectric material prevents electrical continuity through the housing even if the body of the DC connector burns.

[0091] The housing may have at least one exterior surface configured to direct water to an edge of the housing. In other words, the housing may be configured to repel water that falls onto it. This may be accomplished by contouring the exterior surface of the housing in any of a number of ways.

[0092] The housing (inner housing) described above may be provided in an assembly that also includes an outer housing. In this case, the outer housing is configured to receive the device in an internal cavity defined by an inner surface of the outer housing. The outer housing may be configured to hold together at least two parts (components) of the housing (inner housing). In other words, the outer housing may be configured to act as a retention mechanism for holding together the parts (components) of the housing (inner housing).

[0093] The outer housing may be configured to cover at least one port provided on the device. The outer housing may be provided with at least one channel extending therethrough, which may provide at least one third port. The location of the third port may be selected such that the first, second and third ports are not aligned or are only partially aligned (i.e., the ports are not fully aligned) when the outer housing is assembled with the housing (inner housing), as described above. This helps to prevent water ingress and flame escape.

[0094] At least a portion of the inner surface of the outer housing may be at least partially coated with an expandable material that may be proximate to at least one port (e.g., the first port and / or the second port) provided by the device and / or that may be proximate to a third port.

[0095] The outer housing may include a bracket configured for attachment to a support structure.

[0096] The assembly may include at least one split grommet configured to be disposed within the outer housing to receive a DC cable (direct current cable) connected to at least one of the mating DC connectors.

[0097] The outer housing has at least one exterior surface configured to direct water to an edge of the outer housing. In other words, the outer housing may be configured to repel water that falls onto it. This may be accomplished by contouring the exterior surface of the housing in any of a number of ways.

[0098] The assembly may further include a mating DC connector. The DC connector may be associated with a respective manufacturer's rating. The size of the air gap may be configured to allow the DC connector to operate at or below the most restrictive of said ratings. The air gap may be 5 mm or greater (at least 5 mm).

[0099] Although the subject matter of the present invention has been described in language specific to structural features and / or methodological acts, the subject matter defined in the appended claims should not necessarily be limited to those specific features or acts. Rather, the specific features and acts are disclosed as example forms of implementing the claims.

Claims

1. An apparatus for an enclosure of a DC connection of a solar panel for solar power generation, comprising a housing having at least two parts, wherein the at least two parts are configured to form a chamber surrounding a pair of mating type DC connectors by a gap when coupled to each other, the housing comprising at least one support structure for disposing the DC connectors at a central portion of the chamber, Apparatus.

2. The at least one support structure is configured to contact at least one cable connected to one of the DC connectors so as to float the DC connector in the air in a central region of the chamber, The apparatus according to claim 1.

3. The at least one support structure is configured to restrict lateral movement of the DC connector in at least one direction, The apparatus according to claim 2.

4. The housing has an inner surface facing the chamber, the inner surface being at least partially coated with an expandable material, The apparatus according to claim 1.

5. Comprising at least one first port for discharging water from the housing, The apparatus according to claim 1.

6. Comprising at least one second port for a flow of air entering and exiting the chamber, The apparatus according to claim 5.

7. The at least one first port and / or the at least one second port provide access positions for a complexly intertwined passage for water outlet, air inlet, and / or air outlet, The apparatus according to claim 6.

8. The at least one first port and / or the at least one second port are located at a distal end of at least a part of the housing, The apparatus according to claim 6.

9. The at least one first port and / or the at least one second port have an inner surface at least partially coated with an expandable material, The apparatus according to claim 6.

10. The housing comprises an upper part and a lower part that engage with each other to surround the DC connectors, The apparatus according to claim 1.

11. The housing comprises a tubular part having two open ends and two end caps configured to cover the open ends of the tubular part, The apparatus according to claim 1.

12. The housing includes a dielectric material, The device according to claim 1.

13. The housing has at least one outer surface configured to direct water toward an edge of the housing, The device according to claim 1.

14. An assembly comprising the device according to any one of claims 1 to 13 and an outer housing, The outer housing is configured to receive the device within an internal cavity defined by an inner surface of the outer housing. Assembly.

15. The outer housing is configured to cover at least one port provided in the device, The assembly according to claim 14.

16. The inner surface of the outer housing is at least partially coated with an expandable material, The assembly according to claim 14.

17. The outer housing includes a bracket configured to be attachable to a support structure, The assembly according to claim 14.

18. The outer housing further includes at least one split grommet configured to be disposed within the outer housing for receiving a DC cable connected to at least one of the DC connectors, The assembly according to claim 14.

19. The outer housing is configured to hold the at least two parts of the housing together, The assembly according to claim 14.

20. The outer housing has at least one outer surface configured to direct water toward an edge of the outer housing, The assembly according to claim 14.

21. The assembly further includes a pair of mating DC connectors having ratings defined by a manufacturer, The size of the gap is selected such that the DC connector is operable below the rating. The assembly according to claim 14.

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