Electrical installation

Abstract

Electrical installation with a plurality of photovoltaic modules (1) arranged on a roof via a supporting structure (2) and connected to electrical cables (3) laid in a cable duct (4, 14) with metallic wire rods, wherein the cable duct (4, 14) is supported on at least one support element (20), characterized in that the support element (20) has a plurality of retaining means (23) for fixing a cable duct (4, 14) and different cable ducts (4, 14) can be fixed to the support element (20) via the retaining means (23).

Description

[0001] The present invention relates to an electrical installation comprising a plurality of photovoltaic modules arranged on a roof via a supporting structure and connected to electrical cables laid in a cable duct with metallic wire rods, wherein the cable duct is supported on at least one support element.

[0002] For example, support structures according to EP 2 525 165 A1 are known for mounting photovoltaic modules on roofs. These support structures allow large-area installations of photovoltaic modules on flat roofs. This type of installation has proven to be efficient, but the electrical cables in such an electrical installation must not be laid loosely, as they could be damaged by weather influences or animals. Furthermore, the waterproofing of the roof must be ensured.

[0003] It is therefore an object of the present invention to provide an electrical installation with a plurality of photovoltaic modules, which enables efficient mounting of the electrical cables in the electrical installation and ensures a protected arrangement of the electrical cables.

[0004] This problem is solved by an electrical installation having the features of claim 1.

[0005] The electrical installation according to the invention comprises a plurality of photovoltaic modules arranged on a roof via a supporting structure and connected to electrical cables arranged in a cable duct with metallic wire rods. The cable duct is supported on at least one support element having a plurality of holding means for securing the cable duct, and different cable ducts can be secured to the support element via the holding means. This allows the support elements to be laid on the roof during assembly, and it can then be determined which cable duct is secured to the support elements. The support elements can be used to secure different cable ducts that have different cross-sections for accommodating electrical cables, which enables effective laying of the electrical cables on a roof with a solar system.Especially on large roof areas, many photovoltaic modules can be effectively connected as part of the electrical installation, with the electrical cables being protected in the respective cable duct.

[0006] Preferably, cable ducts of different widths can be attached to the support element. The cable ducts can each form a groove-shaped receptacle, the width of which can vary, for example, between 5 cm and 30 cm, in particular between 10 cm and 20 cm. This allows different electrical installations to be created on the roof using the same support elements.

[0007] Each support element preferably has upwardly projecting projections, for example cuboid or wedge-shaped projections, on each of which holding means are provided. This allows the cable duct to be mounted higher than a roof, for example at a height between 1 cm and 8 cm, in particular 2 cm and 6 cm. This protects the electrical cables against moisture damage. The projections on the respective support element can have different heights. This also allows the cable ducts to be mounted at different heights, with narrow cable ducts preferably being mounted lower on the support element than wide cable ducts, so that central projections have a lower height than outer projections. Alternatively, the projections can also have the same height.

[0008] In the longitudinal direction of the cable duct, at least two projections are preferably provided on the support element, to which the cable duct is held. The cable duct can, for example, be secured to four different projections by means of holding means. Perpendicular to the longitudinal direction of the cable duct, each support element preferably comprises at least three projections, optionally four or more projections, in order to be able to secure cable ducts of different widths to the support element.

[0009] For efficient fastening, the retaining means can have two upwardly projecting locking ribs, by means of which a wire rod of a cable duct can be secured. The locking ribs can have inwardly projecting locking projections to lock a wire rod of a cable duct into place. The wire rod can be displaceable in its longitudinal direction relative to the retaining means. The wire of the wire rod can have a circular cross-section, but wires with a rectangular or square cross-section can also be used optionally.

[0010] The distance between adjacent wire rods on the cable duct can be less than 5 cm perpendicular to the longitudinal direction. Furthermore, the cable duct can be closed with a cover, for example, a cover grid, to secure the interior of the cable duct. For easy attachment of the cable duct to the support elements, the bottom-side wire rods, which extend in the longitudinal direction of the cable duct, can be fixed to the retaining means, so that the position of the support elements can be varied in the longitudinal direction of the cable duct; in particular, the cable duct can be displaced to a certain extent in the longitudinal direction.

[0011] In a further embodiment, the support element can be made of conductive plastic, an insulating plastic, or a composite material. Optionally, the support element can provide a certain degree of protection against lightning strikes. Furthermore, a UV-resistant plastic that can withstand the effects of weather can be used.

[0012] Each support element can have connecting means on opposite sides by means of which adjacent support elements can be secured to one another. For example, a web can protrude on a first side and another web can protrude on an opposite second side, on which connecting means for a positive connection of adjacent support elements are formed. This also allows several cable ducts to be held side by side using two of the multiple support elements.

[0013] Each support element is preferably placed loosely on the roof with a lower support surface, so that the roof membrane remains undamaged. The weight of the cable duct and electrical wires secures the support elements against lifting.

[0014] The invention will be explained in more detail below using an exemplary embodiment with reference to the accompanying drawings. They show: Fig. 1 a perspective schematic view of an electrical installation according to the invention, and Fig. 2A and Fig. 2B two views of two support elements with different cable ducts.

[0015] An electrical installation comprises a plurality of schematically illustrated photovoltaic modules 1 arranged on a supporting structure 2 on a roof. Such photovoltaic modules 1 can be arranged, for example, on the flat roofs of industrial buildings and are connected to inverters and other components via electrical cables 3.

[0016] For laying the electrical cables 3 connected to the photovoltaic modules, cable ducts 4 and 14 are provided, forming a groove-shaped receptacle for electrical cables 3. Both cable ducts 4 and 14 are supported on a support element 20 that is loosely placed on the roof. Each cable duct 4 and 14 serves to accommodate a plurality of electrical cables 3, with the width of cable duct 4 being greater than the width of cable duct 14.

[0017] The cable duct 4 comprises base wire rods 5 that extend perpendicular to the longitudinal direction of the cable duct 4 and are integrally formed with two lateral wire rods 6 that extend vertically upward, forming a channel-shaped receptacle for the electrical cables 3. A plurality of such base wire rods 5 and lateral wire rods 6 are provided along the length of the cable duct 4, depending on the length of the cable duct 4, which can be laid, for example, in lengths between 50 cm and 5 m, in particular 1 m to 3 m. The bottom wire rods 5 and side wire rods 6 are connected to each other via wire rods 7 and 8 running in the longitudinal direction of the cable duct 4, wherein the wire rods 7 are fixed to the side wire rods 6 and the wire rods 8 are fixed to the bottom wire rods 5. The cable duct 4 can thus be made exclusively from the wire rods 5, 6, 7 and 8 and has a lattice-shaped structure.

[0018] The cable duct 14 is narrower than the cable duct 4 and therefore comprises shorter base wire rods 15, which are integrally connected at opposite ends to upwardly projecting lateral wire rods 16. The base wire rods 15 are connected to wire rods 18 running in the longitudinal direction of the cable duct 14, and the lateral wire rods 16 are connected to wire rods 17 running in the longitudinal direction, so that the cable duct 14 also has a lattice-like structure. The wire rods are shown here with a rectangular cross-section, but can also be round, in particular circular.

[0019] A plastic support element 20 is arranged beneath each cable duct 4 and 14 and is placed loosely on the roof. Each support element 20 comprises upwardly projecting projections 21 and 22, on the upper side of which holding means 23 in the form of locking webs are formed. The locking webs can fix one of the longitudinally extending bottom-side wire rods 8 or 18. The projections 21 and 22 have different heights, with the two middle projections 21 protruding, for example, between 15 and 40 mm relative to a lower support surface, while the higher lateral projections 22 protrude, for example, between 25 mm and 50 mm upwards. Two projections 21 or 22 are provided in each case in the longitudinal direction of the cable ducts 4 and 14, so that each bottom-side wire rod 8 or 18 is fixed to two spaced-apart projections 21 or 22 of the support element 20.

[0020] Each support element 20 comprises connecting means on opposite sides to enable adjacent support elements 20 to be fixed to one another. On one side of the support element 20, connecting means 24 are formed in the form of tabs or webs with openings, while on the opposite side, connecting means 25 are formed in the form of webs or tabs with a projection, which projection can engage the opening of an adjacent support element.

[0021] In the Fig. 2A and Fig.2B, the two support elements 20 are each shown with the cable duct 4 or 14. It can be seen that the cable duct 14 has a smaller width of L1, for example, between 5 cm and 15 cm, while the wider cable duct 4 has a width of L2 of, for example, 15 cm to 25 cm. The cable duct 14 is fixed to the holding means 23 at the two central projections 21, wherein the holding means 23 each fix, for example, by clamping, a wire rod 8 extending in the longitudinal direction at the bottom.

[0022] The wider cable duct 4 is arranged somewhat higher and supported on the two projections 22, on which holding means 23 are also provided for fixing a wire rod 8 running in the longitudinal direction.

[0023] In the illustrated embodiment, the cable ducts 4 and 14 are shown as only a short length. However, in the electrical installation according to the invention, they are designed to be longer. Several support elements 20 can be used for support in the longitudinal direction of a cable duct 4 or 14.

[0024] In the illustrated embodiment, each support element 20 serves to secure two different cable ducts 4 and 14. It is, of course, also possible to secure more than two cable ducts 4 or 14 to the respective support element 20. Furthermore, the type of retaining means 23 or the number and geometry of the projections 21 and 22 can be changed. List of reference symbols 1 photovoltaic module 2 Supporting structure 3 Electrical cable 4 cable duct 5 wire rod 6 wire rod 7 wire rod 8 wire rod 14 cable duct 15 wire rod 16 wire rod 17 Wire rod 18 wire rod 20 support element 21 lead 22 lead 23 Holding devices 24 lanyards 25 lanyards L1 Width L2 Width QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 2 525 165 A1

[0002]

Claims

[1] Electrical installation with a plurality of photovoltaic modules (1) arranged on a roof via a supporting structure (2) and connected to electrical cables (3) laid in a cable duct (4, 14) with metallic wire rods, the cable duct (4, 14) being supported on at least one support element (20), characterized by that the support element (20) has a plurality of holding means (23) for fixing a cable duct (4, 14) and different cable ducts (4, 14) can be fixed to the support element (20) via the holding means (23). [2] Electrical installation according to claim 1, characterized by that cable ducts (4, 14) with different widths can be fixed to the support element (20). [3] Electrical installation according to claim 1 or 2, characterized by that the support element (20) has upwardly projecting projections (21, 22) on each of which holding means (23) are provided. [4] Electrical installation according to claim 3 characterized by that the projections (21, 22) have a different height. [5] Electrical installation according to claim 3 or 4, characterized by that in the longitudinal direction of the cable duct (4, 14) at least two projections (21, 22) are formed on the support element (20). [6] Electrical installation according to one of claims 3 to 5, characterized by that at least three projections (21, 22) are formed on the support element (20) perpendicular to the longitudinal direction of the cable duct (4, 14). [7] Electrical installation according to one of the preceding claims, characterized by that the holding means (23) have two upwardly projecting locking webs by means of which a wire rod (8, 18) of a cable duct (4, 14) can be fixed. [8] Electrical installation according to one of the preceding claims, characterized bythat the cable duct (4, 14) has, on the bottom side, perpendicular to a longitudinal direction, a plurality of wire rods (5, 15) and upwardly projecting lateral wire rods (6, 16), to which wire rods (7, 8, 17, 18) running in the longitudinal direction of the cable duct (4, 14) are fixed. [9] Electrical installation according to one of the preceding claims, characterized by that the support element (20) is made of a conductive plastic. [10] Electrical installation according to one of the preceding claims, characterized by that each support element (20) has connecting means (24, 25) on opposite sides, by means of which adjacent support elements (20) can be fixed to one another. [11] Electrical installation according to one of the preceding claims, characterized by that the support element (20) rests loosely on the roof with a support surface.

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