Module frame

The module frame is the edge structure around a crystalline silicon PV module, and it is the part that clamps hold onto the mounting structure. Frames are often aluminium, so a frame fixed on a steel structure can suffer galvanic corrosion, often around the fastening screws, especially in humid or coastal areas. In those areas the two metals should be insulated from each other. Frame defects recorded in field inspections include corrosion, separated frame joints, cracking, bending, scratches, misalignment and discoloration. Adhesive or tape problems also appear, such as oozed-out or missing adhesive. The frame seal can also fail: it may look degraded, be squeezed out, show signs of moisture getting in, or delaminate. Bad module clamping can leave the module poorly fastened or let the clamp damage the frame. An inappropriate or defective mounting structure can damage the frame or the modules mounted on it. A loose frame is one of the main failures reported early in a module's working life. Frame breakage is treated as its own failure type. At module level, leakage current paths formed between the encapsulant, the glass and the frame are among the strongest factors behind potential induced degradation. Clamping and mounting damage to the frame is found by visual inspection.

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• sentence 1: support check: partial - Passages mention frame defects and clamps damaging/fastening the module or frame, but never define the frame as the edge structure of a c-Si module that clamps hold onto the mounting structure.
• sentence 3: support check: partial - Corrosion, joint separation, cracking, bending, scratches, misalignment, discoloration and adhesive/tape issues are listed across passages, but they are options in documentation, not stated as 'recorded in field inspections' exactly; mostly covered though.
• sentence 6: support check: partial - Loose frame is listed among the most important failures at start of working life, and frame breakage appears as a separate section heading, but the 'treated as own failure type' rests only on a table-of-contents line. -->