Fastening of a support rail for a PV module to a trapezoidal sheet

1. A fastening of a support rail for a photovoltaic module to a trapezoidal rib of a trapezoidal sheet, wherein the support rail comprises an undercut groove with a groove opening arranged on a bottom side of the support rail, the trapezoidal rib comprises an upper side and a slanted side, and the support rail is configured to be positioned transversely to the trapezoidal rib, the fastening comprising:

at least one retaining element comprising:

a fastening section configured to be fastened to the slanted side of the trapezoidal rib, and

an engaging extension non-detachably arranged on the fastening section, the engaging extension being configured to engage the undercut groove in an engaging position,

wherein,

the engaging extension is configured to be insertable through the groove opening into the undercut groove of the support rail in a loose position that is rotated relative to the engaging position,

the bottom side of the support rail in the engaging position is in direct contact with and is held down against the upper side of the trapezoidal rib by the engaging extension, and

each of the at least one retaining element is arranged on a single slanted side of the trapezoidal rib.

2. The fastening as recited in claim 1 , wherein the engaging extension comprises two protrusions arranged in opposing outward directions, the undercut groove is undercut on both sides, and the engaging extension is configured to engage the undercut groove on both sides via the two protrusions.

3. The fastening as recited in claim 1 , wherein the engaging extension and the fastening section are at least one of integrally connected to each other and consist of a one-part unit from a piece comprising a sheet metal or a plastic.

4. The fastening as recited in claim 1 , wherein the engaging extension and the fastening section are formed in a coplanar manner.

5. The fastening as recited in claim 1 , wherein the engaging extension is formed at an angle to the fastening section so that the engaging extension is steeper than the slanted side of the trapezoidal rib.

6. The fastening as recited in claim 1 , wherein the fastening section is configured to be fastened to the slanted side of the trapezoidal rib by screws or rivets.

7. The fastening as recited in claim 1 , wherein the fastening section comprises at least one protrusion on the trapezoidal rib extending beyond a side of the support rail.

8. The fastening as recited in claim 1 , further comprising a spacer comprising at least one of an elastic material and a plastic material, the spacer being arranged between the fastening section and the slanted side of the trapezoidal rib.

9. The fastening as recited in claim 8 , wherein the spacer is fastened to the fastening section in a prefabricated manner.

10. The fastening as recited in claim 8 , wherein the spacer comprises an extension arranged between the upper side of the trapezoidal rib and the support rail.

11. The fastening as recited in claim 1 , wherein the trapezoidal sheet includes at least one additional trapezoidal rib comprising an upper side, the fastening further comprises at least one additional retaining element, the support rail crosses the trapezoidal rib and the at least one additional trapezoidal rib, and the at least one additional retaining element is configured to hold the support rail down against the upper side of the at least one additional trapezoidal rib.

12. The fastening as recited in claim 11 , wherein the support rail crosses exactly two or three trapezoidal ribs, and exactly one additional retaining element is provided which is configured to hold the support rail down against the upper side of exactly one other of the two or three trapezoidal ribs.

13. The fastening as recited in claim 12 , wherein the two or three trapezoidal ribs comprise two outer slanted sides, and the retaining elements are fastened to the two outer slanted sides.

14. The fastening as recited in claim 1 , wherein the support rail comprises a second undercut groove configured to attach the photovoltaic module.

15. An arrangement comprising:

at least two support rails, each of the at least two support rails comprising at least two of the fastenings as recited in claim 1 ; and

a photovoltaic module;

wherein the photovoltaic module is attached to the at least two support rails comprising the at least two fastenings.