Inverter shutdown

An inverter shutdown means the inverter stops converting power and feeding the grid. In the fault state it also opens its AC relay and displays the fault information. Inverters shut down on their own when PV voltage and power fall below the set values, when the AC grid fails, or when the ambient temperature is outside its normal range. Before treating a shutdown as a defect, rule out intended stops. These include a manual OFF or shutdown command from the display or app, a triggered Rapid Shutdown, and a power limit set to zero. Loss of electrical insulation is a likely cause when the shutdown happens after rain or with morning dew and the inverter logs a low insulation or ground fault. After an insulation or grounding fault, the installer has to correct the fault before the inverter will produce power again. The fault can be confirmed by measuring the insulation resistance under dry or wet conditions. Inverter overheating is more likely when the ambient temperature is high, a fan is blocked, or there is not enough airflow around the inverter. Inverter temperature readings help pick out this cause. When an inverter has stopped operating completely, restart it first. Then check components and connections with IR thermography and Voc measurements, replace defective or abnormally hot parts, and update the software.

<!-- review notes

• sentence 3: support check: partial - Manual shutdown and Rapid Shutdown are covered, and a switch for stopping at 0% power limit exists, but the passages do not state the advice to rule out these intended stops before treating a shutdown as a defect.
• sentence 7: support check: partial - The passage lists restart, IRT/VOC checks, replacing defective or abnormally hot parts and software update, but does not state the ordering (restart first, then check) as a sequence. -->