Event 4021
Qualified person
Event message:
Reverse currents or input X polarity reversed
Check generator
Explanation:
The displayed input is in reverse polarity or reverse current has been detected in the input.
Corrective measures:
Check the correct polarity of the connected PV modules.
Ensure correct design and circuitry of the PV array.
If solar irradiation is sufficient, check whether the same voltage is present at the DC inputs.
Ensure that no PV module is defective.