Clear line along cell crack

On a visual inspection, this signature looks like a lighter, clear line along a cell crack. The surrounding encapsulant has turned yellow or brown. Photobleaching works against encapsulant yellowing. It happens along cell cracks and along the borders of the cells. Small cell cracks usually can't be seen by eye, but the bleached line makes them visible. Encapsulant browning takes several years to develop, so expect this contrast on aged modules. Don't mistake it for snail tracks. Those are discolored silver paste on the cell gridlines, which also follows cracks. To confirm the crack underneath, use electroluminescence or UV fluorescence imaging. In an EL image, cracks show as dark lines. The failure modes behind this signature are cell cracks combined with encapsulant discoloration. Delamination along the same crack may also show up as small bubbles.

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• sentence 1: support check: partial - Passages say photobleaching occurs along cracks, makes the crack visible, and EVA is browned, but a 'lighter, clear line' look is only implied by 'bleaching'.
• sentence 4: support check: partial - Passage says browning takes several years to appear, but 'expect this contrast on aged modules' is an inference.
• sentence 7: support check: partial - Cell cracks, encapsulant discoloration and delamination as small bubbles along cracks are stated, but the 'failure modes behind this signature' framing and the bubble detail are only loosely tied to the signature. -->