DC bus overvoltage

DC bus overvoltage is an inverter alarm. It is raised when the inverter detects too high a DC voltage on its internal bus, and some inverters show it as OV-BUS. The bus voltage is the voltage between the positive and negative poles on the DC side of the inverter. Do not confuse it with the OV-DC alarm. OV-DC means the DC input voltage itself is high, and that usually points to string configuration. Start by measuring the DC and AC voltages and comparing them with the voltages shown on the inverter display. If the measured voltages look normal, the likely cause is inside the inverter. Possible causes are internal damage or a wire that came loose during shipping. The manufacturer's fix for this alarm is to replace the inverter.

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• sentence 5: support check: partial - Internal damage and a wire loose during shipping are listed, but the passages don't say they apply when measured voltages look normal.
• sentence 6: support check: partial - Replace Inverter is listed in the solution, but it is one item after testing, not stated as the sole manufacturer fix. -->