Lightning strike

A lightning strike is an external high-voltage event that PV modules are not designed to survive, so it is treated as force majeure rather than as a module failure. The high voltages from lightning can damage bypass diodes, leaving them either open-circuit or short-circuit; Schottky diodes are especially sensitive to high-voltage discharges. A module hit directly can be mechanically broken, with damaged glass or frame and failed bypass diodes, and both kinds of damage can later cause hot spots and safety problems. A lightning strike can also break mechanically weak cell or connection parts, which can lead to burn marks in the module. PV plants are hit more often than the surrounding land because of their large metal structures and cabling, and sites in regions prone to thunderstorms carry the most exposure. To reduce damage, keep wiring loops small to limit induced voltages, protect long cables with screening or surge protection devices, and install surge arrestors as local codes require. A lightning protection system does not make the site safe for people, so all personnel must leave the plant during a thunderstorm, and weather monitoring helps warn crews in advance.

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• sentence 3: support check: partial - Directly hit modules can be mechanically broken with defective glass/frame and bypass diodes (u1, u17), and both defect types may cause hot spots (u1), but the passages don't say they cause safety problems from the physical breakage specifically, though u1 mentions subsequent safety failures generally.
• sentence 5: support check: partial - PV plants being more likely hit due to metal structures and cabling is stated (u3, u12), and u24 lists lightning strikes in thunderstorm-prone regions, but 'carry the most exposure' is not explicitly stated. -->