Squared cracks between cells

This signature is a pattern of backsheet cracks that runs beneath the gaps between cells, so the cracks form squares around the cells. It is a form of backsheet cracking, where damage to the backsheet can be seen as a crack, burst or scratch. The squared pattern can be seen on an affected module from both the front and the rear side. The cause is given as thermo-mechanical stress acting together with photo-oxidative degradation of the backsheet. Do not confuse it with longitudinal cracks under the busbars, or with a crack under a hot cell caused by high temperature. Backsheet cracks can be very deep and can go into the whole backsheet stack, so check how far the cracking reaches.

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• sentence 5: support check: partial - The figure lists the other crack types (longitudinal under busbars, hot-cell/temperature-induced) as distinct types, but nothing explicitly warns against confusing them.
• sentence 6: support check: partial - The passage says cracks can be very deep and affect the backsheet stack, but it does not say to check how far the cracking reaches. -->