High leakage current

High leakage current usually shows up as an inverter protection fault, such as Sungrow fault 12 or a GFCI error that means system leakage current is too high. Weak sunlight or a damp environment can trigger this fault, and the inverter normally reconnects to the grid once conditions improve. If the fault appears in normal conditions, first check that the AC and DC cables are well insulated, and contact the manufacturer if the fault continues. Poor insulation in a module lets current leak to the frame. That costs no power until the inverter faults, but anyone touching uninsulated parts of the string or frame can get an electric shock. High voltage between modules and ground can also drive the leakage current behind potential induced degradation, which cuts string and module power substantially. In some cases it comes with corrosion and delamination. System voltage, inverter topology, array polarity at night and the grounding concept all affect how much leakage current flows. To tell potential induced degradation apart from a plain insulation fault, look for its signatures with electroluminescence imaging, thermography, IV tracing and Voc checks.

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• sentence 1: support check: partial - Passages show Sungrow 12 and GFCI.Err as leakage faults, but nothing says high leakage 'usually' shows up as an inverter protection fault.
• sentence 7: support check: partial - The detection methods (EL, thermography, IV tracing, Voc) are listed to confirm PID and separate it from other module defects, but 'plain insulation fault' is not specifically mentioned. -->