Electrical overstress

Electrical overstress means electrical loads on PV equipment such as current, bias across the cell junction, system voltage and electrical discharge. Accelerated module tests apply these at levels above what modules see in the field. Inside a junction box, bad contacts or corrosion raise the internal resistance, so the box heats up. In the worst case, junction box failure leads to interconnection failure, with module or cell strings shorted or opened, to arcing inside the box, or to loss of insulation. A failed bypass diode can give off enough heat to deform or burn the junction box. A defective or detached junction box raises the risk of electrical arcing and fire. Its contacts can also break and leave live parts exposed to people. On the AC side, high grid or wiring resistance can push the voltage past the inverter's overvoltage limit. The inverter then disconnects and reconnects again and again. Lightning is a major hazard because the metal structures on a solar farm make strikes more likely during electrical storms. The site must be cleared while a storm lasts. To reduce exposure, install grounding cables that send irregular currents to protective ground, and connect only to circuits with the specified overcurrent protection to lower the fire risk.

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• sentence 1: support check: partial - Passage lists electrical discharge, and current, junction bias, system voltage (as indirect light-related factors) as stressors applied at higher-than-field levels, but doesn't define 'electrical overstress' and says the current/bias/voltage are indirect results of light.
• sentence 8: support check: partial - Both facts are in the passages, but they are unrelated: grounding cables are not said to reduce exposure, and the fire-risk advice is a separate instruction (100 A branch-circuit protection) rather than a combined recommendation. -->