Abnormal external conditions trigger the protection for the DC circuit inside the SUN2000. The possible causes are as follows:
|Cause ID 3: Major|
The SUN2000 input is disconnected accidentally, or the PV string output power changes sharply because the PV string is shielded from sunlight.
|Cause ID 10: Major|
The three phases of the power grid are seriously unbalanced, which triggers the protection for the internal control circuit of the SUN2000.
|Cause ID 11: Major|
The grid voltage changes sharply and the SUN2000 input power fails to discharge in a short time, which increases the internal voltage and triggers overvoltage protection.
|Cause ID 12/15: Major|
An unrecoverable fault occurs on a circuit inside the SUN2000.
|Turn off the AC output switch and DC input switch. Then turn on the AC output switch and DC input switch after 5 minutes. If the fault persists, contact Huawei technical support.|