Device and method for attaching cables to a solar cell panel

Abstract

A cable holder (2) for a solar cell panel (1), comprises a tubular retention portion (10), an attachment portion (9), and spacer portion (8) The spacer portion (8) extends away from the retention portion (10) in a direction aligned with the open ends of the retention portion (10). A method of attaching cables (6) to a solar cell panel (1), comprises the use of a cable holder (2). A cable (6) is bundled and placed in the retention portion (10), and a first and a second end (5, 7) of the cable (6) extend from opposite open ends of the retention portion (10). The attachment portion (9) is slid onto an edge (3) on a back side of the panel (1). The first extending end (5) of the cable (6) is positioned over the spacer portion (8) to a first connector (4), and the second extending end (7) of the cable (6) is positioned over the edge (3) to a second connector. The cable (6) is lifted a distance from the back side of the solar cell panel (1).

Description

[0001] DEVICE AND METHOD FOR ATTACHING CABLES TO A SOLAR CELL PANEL

[0002] Field of the invention

[0003] The present disclosure relates to a cable holder for a solar cell panel, comprising a tubular retention portion with open ends, an attachment portion, including a fixing device to be fixed to the solar cell panel, at a first end of the retention portion, and a spacer portion, for gripping a cable and keeping it at a distance from the solar cell panel, at a second end of the retention portion.

[0004] The disclosure also relates to method of attaching cables to a solar cell panel, comprising the use of a cable holder.

[0005] Background

[0006] W02020 / 022880 discloses a cable holding device for guiding cables in a solar cell system. The device is configured to be attached to a metal support structure whereon the solar cell panels are mounted. This cable holding device indeed organises and directs cables and keeps them isolated from the support structure whereon the device is attached. However it is quite space consuming, and the cables need to have an ample length, in order to be directed through these cable holding devices.

[0007] There is, in addition to the problem addressed by the above cable holding device, a need to handle the cables that are delivered with the solar cell panels for their interconnection. According to prevailing regulations, these cables must not contact neither the underside of the solar cell panels nor the roof. So far, short lengths of single cables have been held by metal clips close to the edge of the back side of the solar cell panel. Such clips are only able to hold one single cable at a time. If the cable length is excessive, the cable slack may form loops, which could come into contact with either the back side of the solar cell panel or with the roof, either of which is unacceptable.

[0008] Solar cell panels may, however, be installed in many different configurations, both regarding their number as well as their physical arrangement on the roof. It is difficult for the manufacturer to anticipate the length of cable needed for any possible configuration, and an excessive length of cable is often provided. In order to comply with the regulations, the cable often needs shortening, which is time consuming. There is an urgent need for an efficient solution to the problem of complying with the regulations, even in situations where an excessive length of cable is provided.

[0009] Summary

[0010] It is an object of the present invention to solve, or at least mitigate, parts or all of the above-mentioned problems. To this end, there is provided a cable holder with a spacer portion which extends away from the retention portion in a direction aligned with the open ends of the retention portion.

[0011] Hereby electric cables may be conveniently stored in a bundle underneath a solar cell panel. An excessive length of cable may be bundled up and placed in the retention portion. The retention portion not only keeps the cable from contacting the back side of the solar cell panel, but also keeps the cable out of contact with the roof. Only the length of cable needed at either end for reaching the respective connectors may be allowed to extend from the bundle in the retention portion. The spacer portion holds the cable taut and a distance away from the bottom surface of the solar cell panel. By extending away from the retention portion, the spacer portion may be braced between an edge of the solar cell panel and a connector.

[0012] In one embodiment the spacer portion comprises a longitudinal slit for gripping a cable.

[0013] Hereby a cable may be inserted into the slit and held in place, acting as a strain relief. No further length of cable is pulled from the bundle, and the cable needed to reach the connector is kept taut. The cable is prevented from sliding sideways from the connector into the retention portion. If needed two, or more, cables may be inserted and held taut in the slit.

[0014] In some embodiments the longitudinal slit extends centrally in the spacer portion, from its outer end towards the retention portion.

[0015] Hereby the spacer portion forms two similar halves, which may be in contact with the underside of the solar cell panel, while allowing the cable to enter into the retention portion at a narrow angle.

[0016] In some embodiments the tubular retention portion comprises a longitudinal, sealable opening.

[0017] Hereby the insertion or adjustment of a cable bundle may be simplified. The retention portion, although having having open ends, may also be openable in a direction from one open end to the other. The bundle may be accessible e. g. for adjustment when one, or both, of its ends are fixed at a respective connector. This may ensure that the cable is tightened as much as possible, before the solar cell panel is installed. In an additional embodiment, the retention portion is openable and resealable along more than on single line. For example, a part of the retention portion may be fully detachable, like a lid, which may be screwed, snapped, or otherwise resealable.

[0018] In some embodiments the fixing device in the attachment portion comprises a recess.

[0019] Hereby the attachment portion may grip around a thin edge at the back of the solar cell panel.

[0020] In a further embodiment, the recess has a zig-zag shaped section.

[0021] Hereby the grip of the recess on the thin edge may be improved. Also, the recess is adapted to grip a variety of edges with different thicknesses, since the zig- zag-shaped, inner walls of the recess are deformable, with at least one, but preferably several, contact points on either side of the thin edge.

[0022] In still further embodiments, the retention portion comprises a pull handle, which is arranged transversally to the recess in the attachment portion.

[0023] Hereby the cable holder may conveniently be pulled by hand into its desired position with the thin edge of the solar cell panel extending well into the recess. Also, holding the handle of the cable holder during installation may ensure that the cable holder remains in its position when the extending lengths of cable are pulled towards their respective connectors.

[0024] According to a second aspect, parts or all of the above-mentioned problems are solved, or at least mitigated, by a method wherein a cable is bundled and placed in the retention portion, a first and a second end of the cable extend from opposite open ends of the retention portion, the attachment portion is slid onto an edge on a back side of the solar cell panel, and the first extending end of the cable is positioned over the spacer portion to a first connector, and the second extending end of the cable is positioned over the edge to a second connector, lifting the cable a distance from the surface of the back side of the solar cell panel.

[0025] Hereby a cable may be attached to the underside of a solar cell panel without contact with the underside of the panel and without having to cut the cable in order to shorten it. Standard length cables may be used for a large variety of installations, and with the method, the cables may quickly be adapted to the length needed, and the excess may be stored in the holder. In a further embodiment a forward end of the spacer portion is positioned over a part of the first connector.

[0026] Hereby the cable holder is placed in a position wherein it is braced between the edge of the solar cell panel and the first connector. Due to this, and with the aid of the elasticity of the material in the cable holder, the tension from the cable holder may keep the cable taut and out of contact with the underside of the solar cell panel.

[0027] In further embodiments the first extending end of the cable is arranged in a cable slit.

[0028] Hereby the cable may extend through the slit at an acute angle to the spacer portion wherein the slit is arranged. The cable does not have to be bent to pass from one side of the spacer portion to the other. Rather it may be kept straight, which will facilitate keeping the cable as taut as possible.

[0029] It is noted that embodiments of the invention may be embodied by all possible combinations of features recited in the claims. Further, it will be appreciated that the various embodiments described for the device are all combinable with the method as defined in accordance with the second aspect of the present invention, and vice versa.

[0030] Brief description of the drawings

[0031] The above, as well as additional objects, features and advantages of the present invention, will be better understood through the following illustrative and nonlimiting detailed description of preferred embodiments of the present invention, with reference to the appended drawings, where the same reference numerals will be used for similar elements, wherein:

[0032] Fig. 1 is a diagrammatic view in perspective of a solar cell panel with two cable holders according to the disclosure;

[0033] Fig. 2 is a perspective view of a cable holder according to the disclosure;

[0034] Fig. 3 is a view from the side of the cable holder in Fig. 2; and

[0035] Fig. 4 is a view from the side of the solar cell panel and cable holders of Fig. 1 .

[0036] All the figures are schematic, not necessarily to scale, and generally only show parts which are necessary in order to elucidate the embodiments, wherein other parts may be omitted. Detailed description of the exemplary embodiments

[0037] Fig. 1 illustrates a bottom side of a solar cell panel 1 , with two cable holders 2 mounted thereon. Each cable holder 2 is braced between a surrounding edge 3 of the solar cell panel 1 and a connector 4, to which a first end 5 of a cable 6 is connected. A second end 7 of the cable 6 extends from the opposite end of the cable holder 2. Although the illustration shows two cable holders 2, situations where only one single cable holder is used is conceivable, as well as situations wherein three or more cable holders are arranged on the same panel.

[0038] A spacer portion 8 of each cable holder 2 is positioned on top of the connector 4. The opposite end of the cable holder 2 is formed as an attachment portion 9, which is fixed to the edge 3 of the panel 1 . Since the spacer portion 8 and the attachment portion 9 are unaligned, the cable holder 2 may be braced between the edge 3 of the panel 1 and the connector 4. The connector 4 is in many cases a junction box provided on most types of solar cell panels 1 . Solar cells may be interconnected or connected to external equipment. A bracing effect may be enhanced by the elasticity of the material, typically plastic, in the cable holder 2. In some embodiments, however, the material may be metal. Also, there may be a height difference between the edge 3 of the panel 1 and the connector or junction box 4, further boosting a bracing effect. Despite this, there may also be embodiments wherein the attachment via the attachment portion alone is sufficient for keeping the cable holder 2 in a position where the cables 6 are kept away from both the back side of the panel 1 and from the surface of the roof.

[0039] Between the spacer portion 8 and the attachment portion 9 of each cable holder 2, there is a tubular retention portion 10 with open ends directed towards the spacer portion 8 and the attachment portion 9, respectively. The retention portion 10 may be basket-like, with one or more openings 11 , as seen in the drawings, but in some embodiments, the surrounding wall of the tubular retention portion 10 may be solid. A cable bundle 12 may be contained in the retention portion 10. The length of the cable in the bundle 12 may vary, depending on the length of the first and second cable ends 5, 7, and of the total length of the cable. In some cases, more than one cable 6 may be held in the bundle 12 in the retention portion 10.

[0040] Fig. 2 illustrates the cable holder 2 only, without a cable arranged therein. The central retention portion 10 comprises a storage space for the cable bundle 12. In some embodiments, the retention portion 10 may be openable along a longitudinal, resealable slit, in order to increase the accessibility of the storage space, but in the illustrated embodiment the cable bundle 12 is inserted from either one of the open ends of the retention portion 10.

[0041] The spacer portion 8, extending from one end of the retention portion 10, serves to separate the cable 6 from the bottom side of the solar cell panel 1 and to guide the cable 6 from the connector or junction box 4 into the retention portion 10. A central, longitudinal slit 13 is arranged in the spacer portion 8. The cable 6 may extend through the slit 13 at an acute angle to the spacer portion 8. Thereby the first end 5 of the cable 6 may be kept as taut as possible, and it does not have to bend unnecessarily to pass from one side of the spacer portion 8 to the other. Another advantage is that the slit 13 may accommodate cables 6 coming from locations at different distances from the edge 3 of the panel 1 . The cable holder 2 may hereby be useful at a large variety of solar cell panels 1 . The risk of the cable 6 coming into contact with the bottom side of the solar cell panel 1 is hence eliminated. Also, the slit 13 may accommodate two or more different cables 6 if needed.

[0042] The spacer portion 8 forms two symmetrically arranged parts 14 on either side of the central slit 13. The lower side (as seen in Fig. 2) of the spacer portion 8 may primarily contact the connector or junction box 4 in order to be braced against it. Possibly the spacer portion 8, or any other part of the cable holder 2 contacts the bottom side of the solar cell panel 1 , but the cable 6 inside the cable holder 2 is lifted away from, and isolated from, contact with the panel 1 .

[0043] A part of the attachment portion 9 may be seen through one of the openings 11 in the retention portion 10 in Fig. 2. A clearer view of the attachment portion is seen in Fig. 3. The attachment portion 9 is preferably provided with a recess 15 with an outwards open end. A thin rim on the edge 3 of the solar cell panel 1 may enter the recess 15, such that the recess forms a fixing grip with the rim. The inner sides of the recess 15 preferably has a zig-zag shape, which may be more or less flattened out, depending on the thickness of the rim. Hereby a secure fixing, with contact points on both inner sides of the recess 15 with the rim is ensured. In some other, not illustrated, embodiments the attachment portion 9 may include other types of fixing elements, such as grooves, barbs, hooks, clasps, adhesives, magnets, etc.

[0044] In use, the installer of the solar cell panels 1 bundles the cable 6 tightly, and may secure the bundle 12 with a strap, before placing it in the retention portion 10 of the cable holder 2. The first end 5 of the cable is attached to the connector 4. Then the first end 5 of the cable 6 is inserted into the slit 13 of the spacer portion 8, and the length of the first end 5 may be adjusted as necessary. The spacer portion 8 is braced on the connector 4 and the attachment portion 9 is fixed to the edge 3 of the panel 1 . In order to fix the attachment portion 9 to the edge 3 of the panel 1 , the installer may use one of the openings 11 of the retention portion 10 as a handle and pull the cable holder 2 towards the edge 3, such that a rim thereof may enter the recess 15. The first end 5 of the cable 6 now extends tightly through the slit 13 and the second end 7 of the cable 6 extends over the attachment portion 9. Any excess of the cable 6 is contained in the bundle 12 in the retention portion 10.

[0045] In Fig. 4, the solar cell panel 1 and two cable holders 2 mounted thereon are seen from the side. The cable holders 2 have each been braced between a respective connector 4 (see Fig. 1 ), from which the first end 5 of the cable 6 extends, and the edge 3 of the panel 1 . The second end 7 extends away from the cable bundle 12 in the cable holder 2 and may be connected to other connector on other equipment as necessary. The cable ends 7 extending outside of the cable holders 2 may be kept taut as there is no excessive length of cable. In effect, the cable 6 has been shortened, without the troublesome and time-consuming task of cutting the cable 6 and reassembling any electrical connectors thereon.

[0046] The invention has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended patent claims.

[0047] In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality.

Claims

Claims1 . Cable holder (2) for a solar cell panel (1 ), comprising a tubular retention portion (10) with open ends, an attachment portion (9), including a fixing device (15) to be fixed to the solar cell panel (1 ), at a first end of the retention portion (10), and a spacer portion (8), for gripping a cable (6) and keeping it at a distance from the solar cell panel (1 ), at a second end of the retention portion (10), wherein the spacer portion (8) extends away from the retention portion (10) in a direction aligned with the open ends of the retention portion (10).

2. Cable holder (2) according to claim 1 , wherein the spacer portion (8) comprises a longitudinal slit (13) for gripping a cable (6).

3. Cable holder (2) according to claim 1 or claim 2, wherein the longitudinal slit (13) extends centrally in the spacer portion (8), from its outer end towards the retention portion (10).

4. Cable holder (2) according to any of the preceding claims, wherein the tubular retention portion (10) comprises a longitudinal, sealable opening.

5. Cable holder (2) according to any of the preceding claims, wherein the fixing device in the attachment portion (9) comprises a recess (15).

6. Cable holder (2) according to claim 5, wherein the recess (15) has a zig-zag shaped section.

7. Cable holder (2) according to 5 or claim 6, wherein the retention portion (10) comprises a pull handle (11 ), which is arranged transversally to the recess (15) in the attachment portion (10.

8. Method of attaching cables (6) to a solar cell panel (1 ), comprising the use of a cable holder (2) according to any of claims 1 to 7, wherein a cable (6) is bundled and placed in the retention portion (10), a first and a second end (5, 7) of the cable (6) extend from opposite open ends of the retention portion (10), the attachment portion (9) is slid onto an edge (3) on a back side of the solar cell panel (1 ), and the first extending end (5) of the cable (6) is positioned over the spacer portion (8) to a first connector (4), and the second extending end (7) of the cable (6) is positioned over the edge (3) to a second connector, lifting the cable (6) a distance from the surface of the back side of the solar cell panel (1 ).

9. Method according to claim 8, wherein a forward end of the spacer portion (8) is positioned over a part of the first connector (4).

10. Method according to claim 8 or claim 9, further comprising the use of a cable holder (2) according to claim 2, wherein the first extending end (5) of the cable (2) is arranged in the cable slit (13).

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