Patent Publication Number: US-9425734-B2

Title: Junction cover for photovoltaic panel modules

Description:
This application is a continuation-in-part of application Ser. No. 13/180,955, filed on Jul. 12, 2011 and claims priority from provisional application Ser. No. 61/363,544, filed on Jul. 12, 2010, all of which are hereby incorporated by reference herein in their entirety for all purposes. 
    
    
     FIELD OF INVENTION 
     The present invention relates to a junction cover, a system that includes a junction cover and a method for covering wiring at junctions between electrical junction boxes for photovoltaic panel modules and wiring conduits, wireways and/or raceways. 
     BACKGROUND OF THE INVENTION 
     Photovoltaic (“PV”) panels, also known as solar panels, are well known in the art for converting solar energy into electrical energy. As used herein, the term photovoltaic refers to the generation of a voltage when radiant energy falls on the boundary between dissimilar substances, such as two different semiconductors. As the desirability for clean and efficient energy sources increases, so does the desire to use power sources such as PV panels. 
     When PV panels are installed, the wiring is routed to a junction box on the backside of the module. Positive and negative wires leave the junction box and are connected to the wires of the adjacent modules (also referred to as inter-module wiring). The wiring for all of the PV panels in a system is then connected to the main power line for the site. Since PV panels are typically located on the roofs of structures, the panel wiring is often subject to extreme weathering conditions and abrasion by animals can degrade and damage the wiring&#39;s insulation. Damage to the wiring can require costly service repairs and can keep the affected panels offline until such repairs are made. Best practice would be to protect all inter-module wiring in a conduit. However, this is not a standard today due to the high cost that is involved. Accordingly, there is a need for a cost effective and efficient system to protect the wiring for PV panels. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a junction cover for a photovoltaic (PV) panel module system that includes a PV panel mounting structure, a rail, a PV module with a junction box and wiring extending between the rail and the junction box. 
     In a first embodiment, the junction cover also includes a member extending upwardly from each of the feet to a distal end. Each of the members has a notch near the distal end on the side of the member facing the open end of the nose section, which is adapted to engage the rail. The open end of the nose section, the feet and the members define a channel that is adapted to receive the rail. When the notches engage the rail and the PV panel is attached to the PV panel mounting structure, the junction cover cannot be removed without detaching the PV panel from the mounting structure. The side walls extend from the base section to the feet and define the open end of the nose section and an open end of the base section. Preferably, the side walls extend outwardly from the plate and are arcuately shaped. The first and second side walls can also curve inwardly towards each other as they extend in the direction of the members. The first embodiment of the junction cover can also include a planar section of the plate that extends from the open end of the base section. 
     In a second embodiment, the junction cover also includes a plurality of cover retaining members extending from the interior surface, which are adapted to secure the junction cover to the junction box. Each of the cover retaining members is formed by one or more ribs having a stepped receiving portion for receiving the corners of the junction box to secure the cover to the junction box. Each of the side walls can also have two flexible legs that include the cover retaining members. At least one of the legs can have an aperture adjacent to the ribs. To remove the cover from the junction box, a tool is inserted into one of the apertures to disengage one of the stepped receiving portions from a corner of the junction box. The base section is dimensioned so that the legs can accommodate junction boxes having different dimensions. Each of the feet has a substantially flat bottom that is substantially parallel to the plate of the base section. The feet are inserted between the rail and the PV panel. 
     In a third embodiment, the junction cover for a photovoltaic (PV) panel module system encloses the junction box and the wiring between the mounting rail and the junction box. The junction box includes a lid and a wire housing. The lid has a plurality of sides and is releaseably attached to the junction box. The wire housing includes a top plate having proximal and distal ends, first and second sides and first and second side walls extending downwardly from the first and second sides. The top plate extends from the proximal end connected to a first side of the lid and slopes downwardly to the distal end. The top plate and side walls define an interior and an opening at the distal end. When the lid is attached to the junction box, the wiring extending between the rail and the junction box is within the wire housing. 
     The lid can have a perimetrical side wall extending downwardly and continuously from the plurality of sides, which sealably encloses the junction box. The lid can include one or more attachment means for securing the lid to the junction box; preferably, the lid comprises one or more attachment means on at least two of the plurality of sides. The attachment means can be prongs or latches extending from one or more of the plurality of sides of the lid. The prongs engage apertures in the junction box or the latches engage catches on the junction box. The attachment means can also be clips that extend from one or more of the plurality of sides of the lid. The clips engage recessed areas on the exterior of the junction box to secure the lid to the junction box. 
     The side walls can be triangularly shaped and substantially parallel. The side walls can also extend inwardly towards one another between the proximal and distal ends. Each of the first and second side walls of the wire housing has a first height at the proximal end and a second height at the distal end. Preferably, the first height is at least twice as high as the second height. Preferably, the side walls of the wire housing extend below the perimetrical side wall of the lid. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The preferred embodiments of the junction cover for PV panels of the present invention, as well as other objects, features and advantages of this invention, will be apparent from the accompanying drawings wherein: 
         FIG. 1  shows a perspective view of a first embodiment of the junction cover for a photovoltaic (PV) panel module. 
         FIG. 2  shows a side view of the first embodiment of the junction cover for a photovoltaic (PV) panel module of  FIG. 1 . 
         FIG. 3  shows a top, exterior view of the first embodiment of the junction cover for a photovoltaic (PV) panel module of  FIG. 1 . 
         FIG. 4  shows an end view of the first embodiment of the junction cover for a photovoltaic (PV) panel module of  FIG. 1 . 
         FIG. 5  shows a bottom, interior view of the first embodiment of the junction cover for a photovoltaic (PV) panel module of  FIG. 1 . 
         FIG. 6  shows a mounting system for photovoltaic (PV) panels with a plurality of the first embodiment of the junction cover of  FIG. 1  secured to the rail. 
         FIG. 7  shows a bottom perspective view of a PV panel with the junction boxes being connected to the inter-module wiring. 
         FIG. 8  shows a perspective bottom view of a PV panel with a plurality of junction boxes connected to the inter-module wiring. 
         FIG. 9  is a side view of a junction box connected to the inter-module wiring. 
         FIG. 10  shows a top perspective view of the first embodiment of the junction cover installed on the rail for the inter-module wiring. 
         FIG. 11  shows a top perspective view of a PV panel being installed onto a rail with a junction cover. 
         FIG. 12  is a bottom perspective exploded view showing a PV panel with a junction box being attached to a rail with the first embodiment of the junction cover. 
         FIG. 13  is a side view showing the first embodiment of the junction cover being installed on a rail and a PV panel with a junction box being positioned on the rail. 
         FIG. 14  a side view of the first embodiment of the junction cover shown in  FIG. 13  installed on the rail and housing the connection with the junction box on the PV panel. 
         FIG. 15  is a top view of a second embodiment of the junction cover of the present invention. 
         FIG. 16  is a side sectional view of the second embodiment of the junction cover shown in  FIG. 15  taken across section A-A. 
         FIG. 17  is a cross-sectional interior view of the second embodiment of the junction cover of  FIG. 16  taken across section B-B. 
         FIG. 18  is a detailed view of one of the corners of the second embodiment of the junction cover of  FIG. 17  taken across section C-C. 
         FIG. 19  is a bottom perspective view of the second embodiment of the junction cover being installed over a junction box attached to a PV panel. 
         FIG. 20  is a bottom perspective view of the second embodiment of the junction cover shown in  FIG. 19  installed over the junction box attached to the PV panel. 
         FIG. 21  is a side view of the second embodiment of the junction cover shown in  FIG. 19  installed over the junction box attached to the PV panel. 
         FIG. 22  is a top perspective view of a third embodiment of the junction cover of the present invention. 
         FIG. 23  is a bottom perspective view of the third embodiment of the junction cover shown in  FIG. 22 . 
         FIG. 24  is a perspective view of the third embodiment of the junction cover shown in  FIG. 22  prior to installation on a junction box on the back side of a PV panel. 
         FIG. 25  is an enlarged perspective view of the third embodiment of the junction cover shown in  FIG. 24 . 
         FIG. 26  is a perspective view of the third embodiment of the junction cover shown in  FIG. 22  installed on a junction box on the back side of a PV panel. 
         FIG. 27  is an enlarged perspective view of the third embodiment of the junction cover shown in  FIG. 26 . 
         FIG. 28  is a side view of the third embodiment of the junction cover shown in  FIG. 26 . 
     
    
    
     DETAILED DESCRIPTION 
     The present invention relates to junction covers that are used to protect the wires connecting the junction box on a PV panel to the inter-module wiring housed in the PV panel rail mounting system. The junction cover provides a cost effective conduit for the wire to travel between the junction box and the rail mounting system. The junction cover also provides weather and rodent protection for the inter-module wiring. The dimensions of the junction cover can be varied to accommodate different types and shapes of junction boxes on the PV panels as well as different rail profiles. 
     In the first embodiment, one end of the junction cover is attached to the rail mounting system and the second end extends over the junction box when the PV panel is attached to the rail mounting system. In the second embodiment, one end of the junction cover is attached to the junction box and the second end extends under the rail system. The junction covers are designed so that they can be easily repositioned to accommodate the locations of the junction boxes and the wiring termination points on the rail mounting system. In the third embodiment, the junction cover includes a lid that fits over and seals the top of the junction box and a wire housing that extends from one side of the lid to the rail system to protect the wiring from damage. The wire housing slopes downwardly from the lid so that the distal end is adjacent to the rail. 
     A mounting system for installing photovoltaic (PV) panels to a structure, such as a roof, includes a rail for attaching the panels and housing the inter-module wiring, a junction box on each panel and wires connecting the junction boxes and the inter-module wiring housed in the rail. The mounting system allows an array of PV panels made up of a plurality of panels to be mounted in various configurations and the electricity generated by the PV panels to be collected. The mounting system can also include brackets for attaching the rails to the structure. 
     The PV panel modules typically include a module junction box disposed on the underside of the panel. The junction box provides a termination point for the individual photovoltaic cells which make up the PV panel and allows the electricity generated by the PV panel to be collected. The junction boxes can include box connectors for connecting the panel modules together. The panel modules may be electrically connected in series and/or parallel in order to achieve a desired output voltage and/or current. The electricity generated can then be connected to the electrical service of the residence, building or property for use by the property owner or resident. 
     The panel modules are attached to the rail mounting system so that the junction boxes are adjacent to one of a plurality of electrical connection stations on the rail. In order to electrically interconnect the panel modules, at least one electrical connection stations is provided for each PV panel. Each connection station includes electrical module connectors which connect to the junction box connector on the panel modules. The module connectors can be flexible wiring connectors and/or rigid connectors. The connections between the junction boxes and the module connectors allow the panel modules to be easily connected and disconnected (e.g., plugged and unplugged). This facilitates installation and/or disassembly of the panel mounting system. 
     Wiring from the module connectors can run along the length of the rail system to a termination point and can be factory-installed in the rail or the module connectors can be placed within the rail system when the module is installed. If the wire is preinstalled within the rail, an installer would need only to connect the junction box to the module connectors to make the electrical connection for the panel modules. If not, the installer can make the connection to the adjacent module during the installation. In order to provide a protected path for the wiring, a wireway can be provided as part of the rail and can include the connection stations. The wireway can be a generally C-shaped member so that, when it is connected to the rail, it forms an enclosed conduit or partially open raceway. The wireway can be formed of metal, plastic, or other material, such as a carbon composite, and designed so that it clips onto the rail. If the wireway is not integral to the rail system, an outer surface of the rail can include an outwardly extending ridge and a bottom surface with a downwardly projecting rim to facilitate the attachment of the wireway. The wireway can include a hook-shaped lip extending along one end which engages the rim. The other end of the wireway slips over the ridge and secures the wireway to the rail. It is within the contemplation of the present invention that the wireway may be attached to the rail in a number of ways including by the use of fasteners, such as screws and/or bolts. 
     In some embodiments, an array of panel modules can be electrically connected using a common ground or reference line. The power line can be divided into segments to connect the positive terminal of a panel module to the negative terminal of another panel module. As such, an array of panel modules can be electrically connected in a cascading manner where the outputs (positive terminals) of a panel module serve as inputs (negative terminal(s)) for the next panel module in the array. 
     The junction covers can be used to cover wiring at a PV module junction box between the junction box and the rail and/or a wire way of a rail of a PV panel mounting system. Embodiments of the junction covers can be used as part of a PV panel mounting system, such as that described herein and/or in U.S. patent application Ser. No. 12/743,476, filed on Mar. 12, 2010, which is incorporated by reference herein in its entirety. Embodiments of the junction covers can also be used with framed modules, frameless modules, as well as other standard and nonstandard PV modules. Different embodiments of the junction covers can be configured to accommodate different sized and shaped junction boxes and different distances between the junction boxes on PV modules and the rails and/or wire ways of the PV mounting system. 
     The junction covers of the present invention will now be described in terms of the drawings.  FIGS. 1-14  show a first embodiment of the junction cover  10  and  FIGS. 1-5  show the junction cover  10  having a base section  12  formed by a plate  14  with first and second side walls  16 ,  18  extending downwardly therefrom to a pair of edges  20 ,  22  to define an interior  24  with an interior surface  26 . The junction cover  10  also includes a nose section  28  extending from the base section  12  to an open end  30 . The nose section  28  has a top wall  32 , two sides  34 ,  36  formed by the side walls  16 ,  18  of the base section  12  and an open side  38  opposite the top wall  32 . A pair of feet  40 ,  42  extends from either side of the open end  30  of the nose section  28 . The feet  40 ,  42  engage the rail  84  ( FIGS. 10 and 14 ) to secure the junction cover  10  in place. A member  44 ,  46  extends upwardly from each of the feet  40 ,  42  to a distal end  48 ,  50 . The members  44 ,  46  have notches  52 ,  54  near the distal ends  48 ,  50  on the side  56 ,  58  of the members  44 ,  46  facing the open end  30  of the nose section  28 . 
     The side walls  16 ,  18  extend from the base section  12  to the feet  40 ,  42  and define the open end  30  of the nose section  28  and an open end  60  of the base section  12 . The open end  30  of the nose section  28 , the feet  40 ,  42  and the members  44 ,  46  define a channel  62  (see  FIG. 2 ) that is adapted to engagingly receive the rail  84  ( FIG. 14 ). The base section  12  can also include a planar section  64  of the plate  14  that extends from the open end  60  of the base section  12 . In addition, the base section  12  and/or the nose section  28  can have a plurality of apertures  66  to provide ventilation and prevent water from collecting in the cover  10 . 
       FIGS. 6-14  show a photovoltaic (PV) panel module system  80  that includes a PV panel mounting structure  82  with a rail  84  and a PV module  86 . A junction box  88  is attached to the rear surface  90  of the PV panel  86  (opposite the surface disposed towards the sun) and wiring  92  extends between the rail  84  and the junction box  88 . As shown in  FIG. 6 , the PV panel module system  80  is typically attached to a structure  94 , such as the roof of a building. The PV panel mounting structure  82  is used to support one or more PV modules  86 . The junction boxes  88  on the rear of the PV modules  86  are electrically connected to the inter-module wiring  96  housed in the rail  84  via an electrical connection station  98  on the rail  84 . Generally, one electrical connection station  98  is provided for each PV module  86 . 
       FIG. 6  shows how the junction covers  10  are attached to the rail  84  in locations corresponding to the junction boxes  88  on the PV modules  86 .  FIG. 7  shows the wiring  92  from the junction boxes  88  being connected to the electrical connection stations  98  on the rail  84 .  FIG. 8  shows a bottom view of the PV panel module system  80  after the PV modules  86  have been attached to the panel mounting structure  82 .  FIG. 9  shows a side view of the connection between the junction box  88  and the electrical connection station  98 . This figure illustrates how the wiring  92  between the junction box  88  and the electrical connection station  98  is exposed.  FIG. 10  shows a cover  10  attached to a rail  84  prior to the installation of the PV panel  86  on the PV panel mounting structure  82  and  FIG. 11  shows the PV panel  86  being placed onto the cover  10  and the mounting structure  82 . 
       FIG. 12  shows a bottom exploded view of a PV panel  86  with a junction box  88  being positioned on the mounting structure  82  so that the cover  10 , which is already installed on the rail  84 , receives the junction box  88  and the wiring  92 . The installation of the PV panel  86  is shown in more detail in  FIGS. 13 and 14 . When the rail  84  is positioned in the channel  62  and the notches  52 ,  54  ( FIG. 1 ) engage the rail  84 , the PV panel  86  is securely attached to the PV panel mounting structure  82  (as shown in  FIG. 14 ) and the junction cover  10  cannot be removed without detaching the PV panel  86  from the mounting structure  82 . 
       FIGS. 15-21  show a second embodiment of the junction cover  110  and  FIGS. 15-18  show the junction cover  110  having a base section  112  formed by a plate  114  with first and second side walls  116 ,  118  extending downwardly therefrom to a pair of edges  120 ,  122  to define an interior  124  with an interior surface  126 . The junction cover  110  also includes a nose section  128  extending from the base section  112  to an open end  130 . The nose section  128  has a top wall  132 , two sides  134 ,  136  formed by the side walls  116 ,  118  of the base section  112  and an open side  138  opposite the top wall  132 . A pair of feet  140 ,  142  extends from either side of the open end  130  of the nose section  128 . The feet  140 ,  142  engage the rail  184  ( FIGS. 19 and 21 ) to secure the junction cover  110  in place. 
     The base section  112  can also have four flexible legs  144 ,  146 ,  148 ,  150  extending from the side walls  116 ,  118 . The legs  144 ,  146 ,  148 ,  150  can further define the interior  124  and form part of the interior surface  126 . One or more ribs  152  having a stepped receiving portion  154  ( FIG. 18 ) extend(s) from the interior surface  126  of the flexible legs  144 ,  146 ,  148 ,  150 . The stepped receiving portions  154  receive the corners of the junction box  188  to secure the junction cover  110  to the junction box  188 . Two of the legs  144 ,  146  have an aperture  156  adjacent to the one or more ribs  152 , and a tool (not shown) can be inserted into at least one of the apertures  156  to remove the junction cover  110  from the junction box  188 . The base section  112  and/or the nose section  128  can also have a plurality of apertures  166  to provide ventilation and prevent water from collecting in the cover  110 . 
       FIGS. 19-21  show the second embodiment of the junction cover  110  being used with a photovoltaic (PV) panel module system substantially the same as the one shown in  FIGS. 6-14 .  FIG. 19  shows a junction box  188  mounted on the rear surface  190  of a PV panel  186  (opposite the surface disposed towards the sun) and wiring  192  connecting the rail  184  and the junction box  188 . The rail  184  is part of the PV panel mounting structure  182  for the PV panel module system. 
       FIG. 19  shows the junction cover  110  being placed over a junction box  188  that is attached to a PV panel  186  so that the ribs  152  ( FIG. 17 ) engage the corners of the junction box  188  to secure the junction cover  110  to the junction box  188 .  FIG. 20  shows the junction cover  110  after it is installed on the junction box  188  with the feet  140 ,  142  of the junction cover  110  positioned between the rail  184  and the PV panel  188 .  FIG. 21  shows how the junction cover  110  covers the junction box  188  and the wiring  192  ( FIG. 19 ) connecting the junction box  188  to the rail  184 . The rail  184  is part of the mounting structure  182 , which is used to attach the PV module  186  to a structure  194 . 
     The third embodiment of the junction cover  210  is shown in  FIGS. 22-28 .  FIGS. 22 and 23  show a top perspective view and a bottom perspective view, respectively, of the junction cover  210 , which includes a lid  212  and wire housing  214 . The wire housing  214  is formed by two side walls  216 ,  218  that extend downwardly from a top plate  220 . The proximal end  222  of the top plate  220  is connected to the lid  212  and the top plate  220  slopes downwardly and away from the lid  212  to a distal end  224  to define an interior space  226  beneath the top plate  220  and between the side walls  216 ,  218 . Because the top plate  220  slopes downwardly from the lid  212 , the side walls  216 ,  218  have a greater height at the proximal end  222  than at the distal end  224  of the wire housing  214 . 
     The lid  212  has a base plate  230  and a perimetrical side wall  232  that extends downwardly, and preferably continuously, around the base plate  230 . The perimetrical side wall  232  has one or more fastening means, such as the latches  234  shown in  FIGS. 22 and 23 , for securing the lid  230  to a junction box  288  (see  FIG. 25 ). The latches  234  engage catches  294  on the exterior wall of the junction box  288  and, after the latches  234  are secured in the catches  294 , the junction cover  210  is securely and releasably attached to the junction box  288 . 
       FIG. 24  shows the back side of a PV panel  286  attached to a pair of mounting rails  284 . A junction box  288  is mounted next to one of the rails  284  and the junction cover  210  is placed over the junction box  288 .  FIG. 25  shows the rail  284 , junction box and junction cover  210  in  FIG. 24  in more detail. In particular,  FIG. 25  shows how the latches  234  on the lid  212  of the junction cover  210  align with the catches  294  on the junction box  288 .  FIG. 25  also shows the wires or cables  292  for the electrical circuits in the PV panel  286  that are connected between the rail  284  and the junction box  288 . 
       FIGS. 26 and 27  show the junction cover  210  after it is installed on the junction box  288  mounted on the back of a PV panel  286 . After the latches  234  are locked onto the catches  294 , the junction cover  210  is secured to the junction box  288  and the wires or cables  292  (see  FIG. 25 ) are enclosed by the wire housing  214  and protected from damage. The shape of the lid  210  can vary to fit the dimensions of the junction box  288 .  FIG. 28  is a side view of the PV panel  286 , mounting rails  284  and the junction cover  210  shown in  FIGS. 26 and 27 . The distal end  224  of the wire housing  214  (see  FIG. 22 ) extends under the mounting rail  28  so that the wires/cables  292  (see  FIG. 25 ) are protected between the rail  284  and the junction box  288 . 
     Having described the preferred embodiments herein, it should now be appreciated that variations may be made thereto without departing from the contemplated scope of the invention. Accordingly, the preferred embodiments described herein are deemed illustrative rather than limiting the true scope of the invention being set forth in the claims appended hereto.