TRUNK BUS SYSTEM

A trunk bus connector for electrically coupling one or more branch cables to a trunk line may comprise a junction area where one or more stripped portions of the branch cable(s) can be secured against a stripped portion of the trunk line. The trunk bus connector may comprise an overmold substantially encapsulating the junction area and comprising a trunk line pathway to enable the trunk line to pass through the junction area. The overmold may comprise one or more branch entry pathways to enable the branch cable(s) access into the junction area. Each branch entry pathway may be angled with respect to the trunk line pathway such that the branch cable(s) enter into the junction area such that an angle at which each branch cable approaches the trunk line is between approximately 30 and 50 degrees.

FIELD OF THE DISCLOSURE

The present disclosure is related generally to the collection of solar power and efficient transmission of captured solar-generated electricity to one or more inverters for delivery to a power grid, energy storage device, and/or another electric consumer. More particularly, in some embodiments, the present disclosure relates to a trunk bus system that may enable better connection of one or more solar panels to an inverter or other electrical component.

BACKGROUND

Solar panels have long been used to capture energy from the sun and convert the energy into electricity, specifically, direct current (DC) electricity. In many applications, the electricity from a panel or several panels may be delivered to an energy storage device (e.g., battery) or other electrical component that may convert, store, or otherwise use the energy. When the generated electricity is to be provided to an alternating current (AC) system (e.g., electric grid, household, etc.), deliver the electricity collected by solar panel(s) to an inverter that converts the electricity from DC to AC and passes the AC electricity onto the consumer (grid, household, etc.).

One conventional method of installing solar power DC wires is to connect a plurality of conducting (e.g., copper) photovoltaic extender wires from solar strings to a combiner box, and then combine several DC feeder lines from combiner boxes to an inverter. To implement this method, on-site technicians must pull the wires, cut the wires to length, crimp connectors, and connect to the combiner boxes. Another method involves using a thick cable, called a trunk bus or trunk line, to carry electricity collected from multiple solar panels to an inverter, where individual strings of solar panels connect to the trunk bus at designated points.

BRIEF SUMMARY

A trunk bus connector for electrically coupling one or more branch cables to a trunk line may comprise a region of electrical contact where one or more stripped portions of the one or more branch cables can be secured by the connector against a stripped portion of the trunk line to electrically couple the one or more branch cables to the trunk line. The trunk bus connector may comprise an overmold substantially encapsulating the region of electrical contact and comprising a trunk line pathway to enable the trunk line to pass through the region of electrical contact. The overmold may comprise one or more branch entry pathways to enable the one or more branch cables access into the region of electrical contact. Each of the one or more branch entry pathways may be angled with respect to the trunk line pathway such that the branch cable(s) enter into the region of electrical contact such that the one or more branch cables enter into the region of electrical contact to be coupled with the trunk line such that an angle at which each branch cable approaches the trunk line is between approximately 30 and 50 degrees. Embodiments of the trunk bus connector may include a crimp configured to secure the stripped portion(s) of the branch cable(s) and the stripped portion of the trunk line together. The crimp may comprise a substantially tubular body forming a channel through which the stripped portion of the trunk line can pass. The crimp may comprise two semi-cylindrical members that, when mated, form the tubular body, and helical and/or straight grooves for stripped portion(s) of the branch cable(s) may run along the channel to secure the stripped portion(s) of the branch cable(s) in the grooves to the stripped portion of the trunk line in the channel.

According to this disclosure, an example method of electrically coupling one or more branch cables to a trunk line may include stripping a portion of the trunk line and stripping one or more portions of the one or more branch cables to be electrically coupled to the trunk line. The method may further include a connector on the trunk line. The connector may comprise a region of electrical contact where one or more stripped portions of the one or more branch cables can be secured by the connector against a stripped portion of the trunk line to electrically couple the one or more branch cables to the trunk line, and an overmold substantially encapsulating the region of electrical contact, the overmold comprising a trunk line pathway to enable the trunk line to pass through the region of electrical contact and one or more branch entry pathways to enable the one or more branch cables access into the region of electrical contact. Each of the one or more branch entry pathways may be angled with respect to the trunk line pathway such that the one or more branch cables enter into the region of electrical contact to be coupled with the trunk line such that an angle at which each branch cable of the one or more branch cables approaches the trunk line is between approximately 30 and 50 degrees. The method may further comprise placing the one or more stripped portions of the one or more branch cables into the connector, and securing the connector to electrically couple the one or more branch cables to the trunk line.

According to this disclosure, an example crimp for electrically coupling one or more branch cables to a trunk line may comprise a substantially tubular body configured to secure one or more stripped portions of the one or more branch cables and the stripped portion of the trunk line together. The tubular body may form a channel through which the stripped portion of the trunk line can pass. Further, the crimp may comprise two semi-cylindrical members that, when mated, form the tubular body. The tubular body may further comprise one or more grooves alongside the channel for the stripped portions of the one or more branch cables. The one or more grooves may be configured to secure the one or more stripped portions of the one or more branch cables against the stripped portion of the trunk line in the channel.

DETAILED DESCRIPTION

As noted, one conventional method of installing solar power DC wires is to connect a plurality of conducting (e.g., copper) photovoltaic extender wires from solar strings to a combiner box, and then combine several DC feeder lines from combiner boxes to an inverter. To implement this method, on-site technicians must pull the wires, cut the wires to length, crimp connectors, and connect to the combiner boxes. This process is very labor-intensive and time-consuming, and the quality of work is very low and inconsistent. Additionally, existing wiring harnesses used to make the connections are labor intensive and yield failed and broken connections that often require rework.

Further complicating matters, more recently, many solar module manufacturers are launching high-wattage power solar panels. Such panels have lower voltage at maximum power (Vmp) but higher short circuit current (Isc). Using existing wiring harnesses and methods, #6AWG copper PV wire, for example, will be required, substantially increasing costs and adding to the Capex value of the solar installation. In addition, due to exposure to severe weather at most sites, combiner boxes installed on-site often malfunction, requiring additional intensive maintenance. Furthermore, to better take advantage of the land, most sites try to go with higher numbers of trackers in a row. However, solar sites are currently limited to 3 or 4 trackers due to DC loss requirements.

Previously, certain trunk busses have been utilized that employ a parallel structure. Disadvantageously, in previous designs, the branch cable (smaller wire) must be bent at least twice: one (approx.) 90-degree bend to move the branch cable conductor down to the trunk line (larger wire) and a second (approx.) 90-degree bend to align the branch cable with the trunk line to facilitate electrical contact between the two. These multiple abrupt bends can lead to wire breaks, complicate installation, and add costs to installation, among other problems.

Embodiments herein address these and other issues by providing a trunk bus system that may be used to electrically connect solar panels and inverters (or other receivers of solar-generated electricity or other electricity) without the need for combiner boxes or the associated combiner box maintenance and installation. By way of just one example, a trunk bus feeder/trunk may be made using 2 kV aluminum photovoltaic wire and may range in sizes from 4/0 to 1000 MCM, but larger or smaller sizes are also contemplated.

Referring now toFIG.1, a top view of an embodiment of a trunk bus110is presented. In certain embodiments, the trunk bus110may include an undermold layer210(shown inFIG.6), an overmold layer111(which also may be referred to as an “outermold”), a trunk line through port112wherein one or more trunk lines512run through, and one or more branch line entry ports113wherein one or more branch lines511enter the trunk bus.

The branch lines511(smaller lines in the figures) may connect to solar panels, and the trunk line512(e.g., the larger, central cable running through the joint, also known as a feeder cable) may be connected to an inverter or to a disconnect box or other electricity receiving device/component, which may, in some embodiments, include a switch and/or fuse protection. By using the trunk bus system, the usage of copper string wires, for example, may be minimized, and larger-size aluminum wires (sizing according to National Electrical Code (NEC) requirements), which are more cost-efficient than copper string wires, may also be utilized. Further, the need for combiner boxes and combiner boxes installation and maintenance can be eliminated. Since, in some embodiments, the main trunk/feeder size can be as large as 1000 MCM, for example, solar farms may exceed more than 4 or 5 high trackers while maintaining DC loss requirements.

Referring now toFIGS.2,3, and4, a bottom, side, and end view of an embodiment of the trunk bus110is presented, respectively. Notably, each view includes an overmold layer111, a trunk line through port112wherein one or more trunk lines512run through, and one or more branch line entry ports113wherein one or more branch lines511enter the trunk bus110.

FIG.5AandFIG.5Bboth display exemplary dimensions of the overmold111of the embodiment of the trunk bus110device shown inFIGS.1-4.

Those skilled in the art will appreciate that embodiments of a trunk bus as provided in this disclosure can eliminate several disadvantages with the parallel connectors commonly found in the prior art. As illustrated inFIG.6, for example, the junction zone510within the trunk bus connector may provide for entry of the branch cable511at an angle513, rather than parallel to the trunk line512, for example, approximately 45 degrees (though other angles are contemplated). One advantage is the elimination of multiple 90-degree bends necessitated by connectors of the prior art. Instead, the branch cable511requires only a single, substantially less than 90-degree bend, thereby eliminating stress on the branch cable511, reducing the number of wire breaks during installation, and simplifying installation overall. The inclined or angled approach shown for example inFIG.6also allows for a greater bending radius of the branch cable511overall, which further protects the branch cable511and reduces installation issues and breaks. Additionally, the inclined or angled approach shown for example inFIG.6further allows for the branch cables511to be shorter, further reducing installation and material costs. Utilizing only a single bend, the branch cable511may approach and lay flat against the trunk line512to be electrically coupled in the area within the undermold210.

FIGS.7A-7Fillustrate certain embodiments of undermold210and branch line511arrangements. Modifications to the overmold111(not shown inFIGS.7A-F) and undermold210allow for the preferred, inclined installation approach taught by this disclosure. In certain embodiments, the undermold210may be manufactured with various dimensions so that multiple different size branch cables511may be accommodated, while still only necessitating a single bend in the branch cables511. In certain other embodiments, the overmold may include multiple branch line entry ports so as to accommodate the coupling of one or more branch cables511to a single trunk line512, thereby resulting in reduced cost, increased efficiency, and easier installation and maintenance of the trunk bus system when utilized in solar electricity generation arrays. It should be noted that there are numerous examples of the number and arrangement of trunk lines511that may enter the undermold210depending on the specific need within the electricity generation array, some of which may not be present inFIG.7A-7Fbut are nonetheless inherently present in the design and this disclosure.

Referring now toFIG.8A-8D, side, bottom, backside, and end views of an embodiment of an undermold210with exemplary dimensions are presented. It should be noted that other examples of the undermold210may also be contemplated to accommodate the potential arrangements of branch cables511displayed and contemplated inFIG.7A-7F.

FIG.9is an illustration that presents an exemplary location of trunk bus devices110disclosed herein, shown relative to the overall architecture of a solar farm910or electricity generation array as they might be installed and used in the field. Those skilled in the art will appreciate that an exemplary trunk bus device110is illustrated with multiple branch cables511extending to multiple solar panels911. Advantageously, the inclined branch cable installation enables case of installation, and better protects the branch cables by allowing for fewer bends of the conductor metal in the connector, and increase bend radius of the branch cable, among other things. Also present inFIG.9is an electrical disconnect box912and an inverter913, both of which are commonly found electrical components necessary for solar array operation.

FIGS.10and11are illustrations of closer views of the portion ofFIG.9designated as Detail A. This portion is of particular interest because it illustrates an exemplary instance of how the presently disclosed trunk bus device110may be arranged for use in a solar array. Particular attention should be directed at how numerous branch lines511may feed into the trunk bus device110, and that multiple trunk bus devices110may be located on a trunk line512. This broader implementation of the presently disclosed trunk bus devices110allows the electrical current produced by multiple solar panels to be consolidated into a single trunk line512before being transferred for further processing.

As noted previously (e.g. inFIGS.7A-7F), different embodiments may accommodate various configurations for coupling one or more branch cables511to a trunk line512. Further, a single type of bus connector may be capable of accommodating different configurations.

FIG.12is an illustration of an example trunk bus connector1200capable of accommodating different configurations of branch cables, depending on desired functionality. In this example, the trunk bus connector1200includes and overmold111with four branch cable ports113-A,113-B,113-C, and113-D (also referred to herein as branch entry pathways or entry ports), enabling up to four branch cables511to couple with a trunk line512in a junction area, or region of electrical contact, substantially encapsulated by the trunk bus connector's overmold111. As previously discussed, portions of the branch cables511and trunk line512within the trunk bus connector1200may be stripped (of the insulator material) to allow electrical coupling of the branch cables511and trunk line512in a junction area substantially encapsulated by the overmold111.

The material(s) with which the overmold111is made may vary, depending on desired functionality. These materials may comprise UV-and weather-resistant materials be selected to help protect the electrical connection(s) from moisture intrusion and corrosion. According to some embodiments these materials may include polyvinyl chloride (PVC), nylon, polycarbonate, silicone rubber, other weatherproof plastics, and/or the like. Materials may be selected, for example, to have a flammability rating of V-1 or above, an outdoor suitability rating of f1, a hot-wire ignition (HWI) rating of 4 or less, a high amp arc ignition (HAI) rating of 3 or less, a relative thermal index (RTI) of 90° C. or more, and a comparative tracking index (CTI) of 2 or less. Santoprene® thermoplastic vulcanizate (TPV), a material produced by Celanese International Corp. of Florence, Kentucky (USA), is one such material.

As described in more detail below, depending on a desired configuration, branch cables511may form terminal connections and/or through connections with the trunk line512. As described herein, a “terminal” connection may be formed when a branch cable511ends inside the trunk bus connector1200. An example of this is illustrated inFIG.6, described above. InFIG.12, the trunk bus connector1200may have up to four terminal connections. That is, each branch cable511entering a respective branch cable port113-A,113-B,113-C, or113-D may comprise a separate branch cable that is electrically coupled with the trunk line512and terminates inside the trunk bus connector1200.

Additionally, or alternatively, branch cables511may represent “through” connections, where a single branch cable511enters one branch cable port113and exits another. For example, a branch cable511may enter the trunk bus connector1200at branch cable port113-A and exit the trunk bus connector1200at branch cable port113-D. This type of through connection, in which the branch cable511enters a trunk bus connector1200on one side of the trunk line512and exits the trunk bus connector1200on the other side of the trunk line512, is referred to herein as a “crossover” through connection. A branch cable511entering branch cable port113-C and exiting the trunk bus connector1200at branch cable port113-B also represents a crossover through connection. In another example, a branch cable511may enter the trunk bus connector1200at branch cable port113-A and exit the trunk bus connector1200at branch cable port113-B. This type of through connection, in which the branch cable511enters a trunk bus connector1200on one side of the trunk line512and exits the trunk bus connector1200on the same side of the trunk line512, is referred to herein as a “same-side” through connection. As described below with respect toFIGS.13A-15B, trunk bus connectors (e.g., trunk bus connectors110or1200) with overmolds111having different numbers of branch cable port113can accommodate various types of configurations.

FIGS.13A-13Fillustrate a set of configurations in which an overmold111of a trunk bus connector1200has four branch cable ports113-A,113-B,113-C, and113-D. (FIG.13Aincludes various labels that are omitted inFIGS.13B-13F, to avoid clutter, but which are applicable to corresponding features.) It can be noted that the trunk bus connector1200may also include an undermold and/or crimp, neither of which are illustrated inFIGS.13B-13F. According to some embodiments, some undermolds and/or crimps may be designed to support particular configurations. Additionally, or alternatively, undermolds and/or crimps may be designed to support multiple configurations. Additional details regarding such designs are provided hereafter. Additionally labeled inFIGS.13A-13Fare junction areas1305, also referred to herein as regions of electrical contact, in which stripped portions (exposed conductors) of branch cables1330lay against a stripped portion of the trunk line1340to electrically couple the branch cables511to the trunk line512. Various types of connections are identified with dashed lines, where crossover through connections are labeled1320-COT, same-side through connections are labeled1320-SST, and terminal connections are labeled1320-T. Finally, it can be noted thatFIGS.13A-13Fare provided as examples and may not represent all configurations in which an overmold111of a trunk bus connector1200has four branch cable ports113-A,113-B,113-C, and113-D.

As illustrated, configurations may include a combination of through and terminal connections.FIG.13Aillustrates a configuration in which two branch cables511form crossover through connections1310-COT with the trunk line512.FIG.13Billustrates a configuration in which two branch cables511form same-side connections1310-SST with the trunk line512.FIG.13Cillustrates a configuration in which three branch cables511form two terminal connections1310-T and one crossover through connection1310-COT.FIG.13Dillustrates a configuration in which three branch cables511form two terminal connections1310-T and one same-side through connection1310-SST.FIG.13Eillustrates a configuration with four branch cables511and four terminal connections1310-T with trunk line512. Finally,FIG.13F, which also shows a configuration in which four branch cables511form four terminal connections1310-T with trunk line512, is provided to illustrate an example of alternative terminal connections which differ from the terminal connections1310-T ofFIGS.13B-13E. Specifically, rather than a terminal connection1310-T in which a portion of the branch cable511runs parallel to the trunk line512, the configuration inFIG.13F(and other configurations not illustrated) may include one or more terminal connections1310-T in which a portion of the branch cable511runs helically around at least a portion of the trunk line512. (Additional details regarding how such helical connections may be formed are provided below.)

FIGS.14A-14Cillustrate a set of configurations that extend aspects of the examples illustrated inFIGS.13A-13Fto a trunk bus connector1400having an overmold111with three branch cable ports. Similar toFIGS.13A-13Fthe trunk bus connector1400may include an undermold and/or crimp, neither of which are illustrated inFIGS.14A-14C. Further, it can be noted thatFIGS.14A-14Care provided as examples and may not represent all configurations in which an overmold111of a trunk bus connector1400has three branch cable ports.

As illustrated, configurations may include a combination of through and terminal connections.FIG.14Aillustrates a configuration in which two branch cables511form a crossover through connection1310-COT and a terminal connection1310-T with the trunk line512.FIG.14Billustrates a configuration in which two branch cables511form a same-side through connection1310-SST and a terminal connection1310-T with the trunk line512.FIG.14Cillustrates a configuration in which three branch cables511form three terminal connections1310-T with the trunk line512.

FIGS.15A-15Dillustrate a set of configurations that extend aspects of the examples illustrated inFIGS.13A-14Cto two types of trunk bus connectors1500and1510having an overmold111with two branch cable ports. In particular,FIGS.15A and15Billustrate a trunk bus connector1500of a first type in which the overmold111has two branch cable ports on the same side of the trunk line512(similar to embodiment illustrated inFIG.1).FIGS.15C and15Dillustrate a trunk bus connector1510of a second type in which the overmold111has two branch cable ports on opposite sides of the trunk line512. Similar toFIGS.13A-14Cthe trunk bus connectors1500and1510may include an undermold and/or crimp, neither of which are illustrated inFIGS.15A-15D. Further, it can be noted thatFIGS.15A-15Dare provided as examples and may not represent all configurations in which an overmold111of a trunk bus connectors1500and1510have two branch cable ports.

As illustrated, configurations may include a combination of through and terminal connections.FIG.15Aillustrates a configuration in which two branch cables511form terminal connections1310-T with the trunk line512.FIG.15Billustrates a configuration in which a single branch cable511forms a same-side through connection1310-SST.FIG.15Cillustrates a configuration in which a single branch cable511forms a crossover through connection1310-COT with the trunk line512.FIG.15D illustrates a configuration in which two branch cables511form terminal connections1310-T with the trunk line512.

As noted above, a trunk bus connector may include an undermold and/or crimp, which may be encapsulated by the open mobile. Returning toFIG.12, for example, trunk bus connector1200may encapsulate an undermold and/or crimp configured to secure the connections between the branch cables511and trunk line512.FIGS.16-20, described below, illustrate examples of an undermold and/or crimp that may be used with a trunk bus connector1200having an overmold111with four branch cable ports. It can be noted, however, that the principles described below can be applied to trunk bus connectors having a different number of branch cable ports, such as trunk bus connectors1400,1500, and1510, illustrated inFIGS.14A-15D.

FIG.16is an illustration of an undermold210of the example trunk bus connector1200ofFIG.12. The material(s) with which the undermold210is made may vary, depending on desired functionality. Because the undermold210is substantially encapsulated by the overmold111, the materials of the undermold210need not necessarily be UV-or weather-resistant. Materials be selected to help secure branch cables511to trunk line512. According to some embodiments, these materials may include materials that have a flammability rating of V-1 or above. Again, Santoprene® TPV is one such material.

FIGS.17A and17Bare illustrations of a crimp1700of the example trunk bus connector1200ofFIG.12(after crimping has taken place). Note that the illustration inFIG.17Ashows a view similar toFIG.12(e.g., a top (plan) view), and the illustration inFIG.17Bshows a rotated view (e.g., a front view). In some embodiments, the crimp1700may be substantially encapsulated by the undermold210ofFIG.16. Additionally or alternatively, as noted, the crimp1700may be substantially encapsulated by the overmold111without the use of an undermold. The crimp1700may be made of a conductive material (such as aluminum, copper, or steel) that holds its shape when a crimping force is applied to press and secure stripped portions of the branch cables511to the trunk line512. As previously noted, the crimp1700may be designed to accommodate one or more different configurations, such as the configurations illustrated inFIGS.13A-13F. Additional details regarding one such design are provided below. (The design discussed below comprises a smaller c-crimp coupled with a larger c-crimp. Seams1710illustrated inFIG.17Bshow the boundaries of these two pieces after crimping.)

In addition or as an alternative to using an overmold, undermold, or both to protect and insulate electrical connections of a trunk bus system as described above, some embodiments may use one or more temperature-activated sealing members, such as a heat shrink tube (HST). In some embodiments, an HST may comprise a thermoplastic member, generally tubular or cylindrical, although variations in shape may be implemented for specific applications. When placed over and underlying structure such as a stripped portion of a wire or cable (and optionally overlapping with an un-stripped portion), applied heat may cause the outer layer of the HST to shrink and conform to an outer shape of the stripped (and optionally un-stripped) portion(s) of the wire or cable. Because of this tight encapsulation of the underlying wire or cable, an HST may provide a hermetic seal that prevents undesirable elements such as moisture, dust, and air from coming into contact with the encapsulated portion(s) of the wire or cable. HSTs may also help provide electrical insulation for stripped portions of the wire or cable encapsulated therewith. As such, HSTs may be used at various locations in a trunk bus system, including at locations where portions of branch cables and/or a trunk line are stripped and crimped (e.g., as illustrated inFIGS.17A and17B). It can be noted that HSTs are not necessarily limited to encapsulating wire or cable, but may be configured to encapsulate other structures, including, for example, all or a portion of a (e.g., crimp1700). HSTs may be manufactured from a variety of thermoplastic materials, such as polyolefins (e.g., polyethylene (PE) and polypropylene (PP)), fluoropolymers (e.g., polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), and polyvinylidene fluoride (PVDF)), polyvinyl chloride (PVC), or the like. Further, an HST may be selected based on specific constraints, such as physical dimensions, fire-retardation rating, electrical resistance, physical dimensions shrinkage range, and/or other parameters.

Depending on desired functionality, HSTs may have a variety of features. In some embodiments, for example, an HST may comprise a temperature-activated adhesive lining an interior surface, causing the HST to adhere to a wire or cable when it shrinks, and helping ensure a seal is formed between the HST and wire or cable. In some embodiments, the temperature-activated adhesive may not be included with the HST, but may be applied prior to use. Some HSTs may comprise “two-segment” HSTs, where a first HST member covers one underlying structure (e.g., wire or cable), and a second HST member covers another underlying structure that may have different physical dimensions (e.g., a thicker wire, crimp, etc.). The first and second HST members overlap such that, after shrinking, the first and second HST members encapsulate the underlying structures and also overlap such that one HST member is partially encapsulated by the other, thereby creating a continuous seal over all underlying structures. Some HSTs may be made of a pliable material that helps form a seal between a structure encapsulated by the HST, and another structure at least partially encapsulating the HST. For example, according to some embodiments, HSTs may be used to encapsulate stripped and un-stripped portions of branch cables511to form a primary seal against the insulated (un-stripped) portions of the branch cables511. The HSTs may also provide a more pliable surface (e.g., compared with the insulator of the uninsulated portions) against which an inner mold210can form a secondary seal. Thus, in such embodiments, HSTs not only may be used to provide a seal directly over exposed wires it (and/or other conductive surfaces), but also help facilitate a seal of encapsulated portions of a trunk bus system by an inner mold210.

FIGS.18A and18Bare illustrations of a configuration with two branch cables511and a trunk line512, prior to crimping. These figures may correspond with the configuration shown inFIG.13Aand are similarly labeled. Specifically, stripped portions of the branch cables1330form a crossover through connection1310with a stripped portion of the trunk line1340.FIG.18Aprovides an overhead view andFIG.18Bprovides a perspective view. As shown by the arrows1800inFIG.18B, the stripped portions of the two branch cables1330following a helical route around the circumference of the stripped portion of the trunk line1340. As described in more detail below, a crimp may be designed to ensure the stripped portions of the two branch cables1330are secured to the stripped portion of the trunk line1340in this manner.

FIGS.19A and19Bare illustrations of a crimp1700, according to an embodiment. For convention in this disclosure, a first end and a second end of the crimp1700have been labeled. It can be noted that other view or orientation descriptors are used below however these are also used for convention. The crimp1700may be used as needed in any suitable orientation.

As indicated,FIG.19Aincludes an overhead view and a cross-section view of the crimp1700, according to an embodiment, which may be used with the trunk bus connector1200described above. As indicated, the overhead view illustrates an A-A section of the crimp1700corresponding to the cross-sectional view.

According to this embodiment, the crimp1700has a tubular body with sidewalls1905forming a channel extending from the first end to the second and through which a stripped portion of a trunk line can run. (Arrow1906indicates a pathway through the channel.) As further illustrated, an inner surface1907of the crimp surrounding the channel may include one or more grooves1910, which run alongside the channel (e.g., in the direction of arrow1906) in a helical pattern. Stripped portions of branch cables may run through these grooves1910, which can help secure the stripped portions of the branch cables to the stripped portion of the trunk line in the manner illustrated inFIGS.18A and18B. The grooves1910illustrated inFIG.19Arepresents portions of two separate grooves, each extending from the first end to the second end of the crimp1700. Additional details our shown inFIG.19B, described below. (It is noted that because the cross-section of the crimp1700shown inFIG.19Ais not perpendicular to grooves1910, the “diameter” of grooves1910represented by arrows1914may represent an approximation of the true diameter of grooves1910. The discussion below referring to diameter1914is intended to refer the true diameter of the grooves1910.)

Dimensions of the crimp may vary depending on the size of the trunk line and/or branch cable(s). For example, according to some embodiments, the diameter1912of the channel may be 20 mm±0.5 mm. According to some embodiments, the diameter1914of the grooves1910may be 5 mm±0.5 mm. More broadly, according to some embodiments, the diameter of1912may fall within a range of 9 mm to 35 mm, and the diameter of1914may fall within a range of 5 mm to 8 mm. These values may be within a degree of tolerance (e.g., 0.5 mm), to allow for a degree of variability in the manufacturing process. Further, according to some embodiments, the ratio of the diameter of1914to the diameter of1912may range from 1:7 to 5:9, depending on the size of the trunk line and/or branch cable(s). (It will be understood that these sizes and ratios are provided as nonlimiting examples; some embodiments may use sizes and/or ratios other than those explicitly provided herein.) Put generally, the diameters1912and1914may be approximately the diameters of the trunk line and branch cable(s), respectively. This can enable an installer to place the stripped portion of the trunk line in the channel and stripped portions of the branch cables into the grooves1910prior to crimping.

FIG.19Bincludes an end view and interior view of components of the crimp1700, according to an embodiment. As illustrated, the crimp may comprise nested c-crimps comprising a smaller c-crimp1920and a larger c-crimp1930, each comprising a semi-cylindrical member that, when mated with the other, forms the tubular body of the crimp1700. The end view is a view of the smaller c-crimp1920and the larger c-crimp1930from an end (e.g., the first end) of the crimp1700, and the interior view is a view of the interior surface1933of the smaller c-crimp1920and the interior surface1935of the larger c-crimp1930.

As shown by the end view, the smaller c-crimp1920may be mated to the larger c-crimp1930as shown by arrow1940. When mated, each1943of the smaller c-crimp fits into a corresponding groove1945(not to be confused with grooves1910for the branch cables).

The interior view distinguishes the labels of the helical grooves to help illustrate how the grooves of the smaller c-crimp1920and the larger c-crimp1930form two separate helical grooves1910-A and1910-B that extend from the first end to the second end. For example, with respect to groove1910-A, when the smaller c-crimp1920and the larger c-crimp1930are mated, opening1950in the smaller c-crimp1920fits with opening1955of the larger c-crimp1930, forming a single groove1910-A extending from the first end to the second end. The second groove1910-B is formed similarly. (The ends of these grooves1910-A and1910-B from the perspective of the first end are illustrated in the end view inFIG.19B.)

FIGS.20A and20Bare illustrations of a perspective and side view of another embodiment of a crimp1700, respectively. Various components of the crimp1700are labeled to match the corresponding labels inFIGS.19A and19B. Further, the perspective view ofFIG.20Aprovides a clear illustration of how a tubular body of the crimp1700forms a channel2000, through which the stripped portion of the trunk line can pass. The side view of the crimp1700shown inFIG.20Bshows the cylindrical shape of the tubular body. The channel2000may be substantially aligned with a trunk line pathway in the overmold of the trunk bus connector to allow the trunk line to pass through both of the overmold and the crimp1700of the connector. Further, because of the angle of the perspective view inFIG.20, only a single helical groove1910is illustrated, although the crimp1700may include a similar groove (not visible) on the other side of the channel2000.

FIG.20Aalso illustrates a clear path of the groove1910. More specifically, it illustrates how the groove1910runs helically at least partially around a circumference of the channel2000, as illustrated by arrow2005. In this embodiment, the groove1910runs in a helical manner substantially 180° circumferentially around the channel. This groove1910(and another groove, not visible, on the opposite side of the channel2000) may allow a branch cable to make a crossover through connection in the manner described in the embodiments above by enabling one or more branch cables to enter a first end of the tubular body of the crimp1700and exiting a second and of the tubular body opposite to the first end.

It can be noted that there are at least two differences in the embodiment of the crimp1700illustrated inFIGS.20A and20Bfrom the embodiment illustrated inFIGS.19Aand19B. First, the tongue1943(and corresponding groove) in the embodiment illustrated inFIG.20Ahas a curved profile. In the embodiments illustrated inFIGS.19A and19B, the tongue has a substantially straight profile. This illustrates how various embodiments may allow a smaller c-crimp1920to mate with a larger c-crimp1930in different ways. Moreover, other embodiments may have additional or alternative tongue-and-groove profiles and/or other mechanisms to allow the coupling of different portions of the crimp1700. It may further be noted that alternative embodiments of a crimp1700may have a single member that does not involve coupling components or may have more than two coupling components. The number of components and/or the profile of the tongue1943may depend on manufacturing concerns, materials used, and/or other considerations.

A second difference in the embodiment of the crimp1700includes the addition of grooves2010. As illustrated, grooves2010may run substantially parallel to the channel2000, and may be located on opposite sides of the channel2000. This can allow for same-side through and terminal connections as described herein. Moreover, as illustrated, the use of straight grooves2010may be combined with the use of helical grooves1910, as illustrated, such that the ends of the grooves meet at a common point at the end of the crimp1700. The use of both straight and helical grooves in this manner can allow for a single crimp1700design that allows for the various configurations illustrated inFIGS.13A-15D, described above. More specifically, the embodiment of the crimp1700ofFIGS.20A and20Bmay accommodate crossover through connections, same-side through connections, and/or terminal connections of one or more branch cables with a trunk line.

FIG.21is a flowchart of a method of electrically coupling one or more branch cables to a trunk line, according to an embodiment. In some aspects, this method may be seen as using the trunk bus connector1200described herein, including the various configurations illustrated inFIGS.13A-15Dand embodiments of the crimp1700described herein. Accordingly, this method may be performed, for example, by a technician in the field when using the trunk bus connector1200in the deployment and/or maintenance of a solar power system.

At block2105, the functionality comprises stripping a portion of the trunk line. This may be performed with the help of a wire stripping tool, for example. The stripped portion of the trunk line may correspond to the stripped portion of the trunk line1340as described herein with respect toFIGS.13A-13F, for example.

At block2110, the functionality comprises stripping one or more portions of the one or more branch cables to be electrically coupled to the trunk line again, this may be performed with the help of a wire stripping tool, for example. The stripped portion of the trunk line may correspond to the various connections1310(e.g.,1310-COT,1310-SST,1310-T) as described herein with respect toFIGS.13A-15D, for example.

At block2115, the functionality comprises placing a connector on the trunk line, the connector comprising (i) a region of electrical contact where one or more stripped portions of the one or more branch cables can be secured against a stripped portion of the trunk line to electrically couple the one or more branch cables to the trunk line; and (ii) an overmold substantially encapsulating the region of electrical contact, the overmold comprising a trunk line pathway to enable the trunk line to pass through the region of electrical contact and one or more branch entry pathways to enable the one or more branch cables access into the region of electrical contact, wherein each of the one or more branch entry pathways are angled with respect to the trunk line pathway such that the one or more branch cables enter into the region of electrical contact to be coupled with the trunk line such that an angle at which each branch cable of the one or more branch cables approaches the trunk line is between approximately 30 and 50 degrees. As indicated in the above-described embodiments, an overmold (e.g., overmold111) of a trunk bus connector can help ensure electrical conductivity the region of electrical contact, or junction area. In some embodiments, this may be done with the help of an undermold (e.g., undermold layer210) and/or crimp (e.g., crimp1700).

The functionality at block2120comprises placing the one or more stripped portions of the one or more branch cables into the connector. This can be done using a desired configuration, such as one of the configurations shown inFIGS.13A-15D, for example. Further, as noted herein, the overmold (and undermold/crimp, if used) may be designed to accommodate the particular or various configurations.

The functionality at block2125comprises securing the connector to electrically couple the one or more branch cables branch cables to the trunk line. This may include, for example, closing the overmold, closing the undermold (if used), and/or crimping the crimp (if used).

Embodiments of the method illustrated inFIG.21may include one or more additional features, if desired as described in the embodiments herein. For example, according to some embodiments, the crimp may comprise a substantially tubular body forming a channel through which the stripped portion of the trunk line can pass. (See, for example,FIGS.20A and20B.) In such embodiments, the channel may be substantially aligned with the trunk line pathway of the overmold. (Compare the alignment of crimp1700inFIG.17Awith overmold111inFIG.12, for example.) In some embodiments, the crimp may comprise two semi-cylindrical members that, when mated, form the tubular body. An example of this is illustrated inFIG.19B, described above. In such embodiments, a first member of the two semi-cylindrical members may have at least one tongue that fits into a corresponding groove of a second member of the two semi-cylindrical members when the first member is mated with the second member. Additionally or alternatively, the tubular body may further comprise one or more grooves alongside the channel for the stripped portions of the one or more branch cables, the one or more grooves configured to secure the one or more stripped portions of the one or more branch cables against the stripped portion of the trunk line in the channel. Examples of such grooves are shown inFIGS.19A-20B(e.g., grooves1910and2010).