Derating

Derating means the inverter is deliberately lowering its output power. It is a normal operating state that can happen now and then, for several different reasons. Derating itself does not harm the inverter. A common cause is temperature: the inverter limits its output when it cannot shed heat, for example because of poor installation conditions or an internal temperature above its derating limits. The inverter can also derate on input current when the PV array delivers more current than the inverter's maximum input. It does this to protect itself from overload. Occasional derating needs no action. If temperature derating happens often, check the heat dissipation and ventilation, and make sure any fans work and are clean. If current derating shows up regularly, an installer should check the system design and how the modules are wired.

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• sentence 5: support check: partial - Normal occasional derating and checking heat dissipation and fans if frequent are stated. 'Ventilation' appears only in the installer section. No explicit 'no action needed' for occasional derating is given. The u33 'No action needed' text is mismatched. -->