Mounting structure

The mounting structure holds PV modules in place on the ground or on a roof. The mounting group of components covers the structure itself plus its clamps and screws. Mounting system types include clamps, rails along the short or long module sides, backrails, roof-integrated and facade-integrated systems, and delta supports. Its main failure mode is an inappropriate or defective mounting structure. Typical causes are a design that cannot take the site's wind or snow loads, weak anchorage to the ground or roof, and roof strength that was never checked. Wrong material choices also cause failures: corrosive materials in a corrosive environment, too little galvanising, or poor-quality material. So do installation errors, such as missing or non-original parts and screws that are too tight or too loose. Where two different metals touch, for example an aluminium frame on a steel structure, galvanic corrosion often starts around the fastening screws. In humid or coastal areas the two metals need insulation between them. Detection is by visual inspection. Look for cracking, bending, or corrosion of the frame or the mounting holes. A damaged structure can harm the modules and the roof. In the worst case modules or the whole structure come loose, or the roof collapses. Performance losses depend on how much damage the modules take.

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• sentence 1: support check: partial - Passages list Mounting as (structure, clamps and screws) and mention anchorage to ground or roof, but never state that the structure holds modules in place on ground or roof as its function (only implied). -->