Sungrow SG1250UD - Alarm Information

Operation Manual 10. Troubleshooting
59
Alarm
LVRT Run
Possible
reason
When the grid voltage is below the min. LVRT normal voltage and the LVRT
function is enabled, this alarm information will be displayed
Measure
The short-time LVRT run alarm will be removed automatically when the grid
returns normal if this alarm is caused by grid fault. If this is a long-time LVRT run
caused by on-site low grid voltage, it is recommended to adjust the transformer
tapping voltage to increase the power yields.
Remark
During LVRT run, the active and reactive power follows the related LVRT
standard and does not follow the background dispatch.
Alarm
CT-Unbalanced
Possible
reason
Current transformer (CT) on the inverter control cabinet is abnormal
Measure
Check and service the CT on the measuring board when inverter is voltage-free
Remark
-
Alarm
RISO-flt
Possible
reason
Inverter DC side insulation resistance is lower than the set value.
Measure
Check the PV panel insulation to the ground when the inverter is voltage-free
Remark
Only alarm display. The inverter can operate normally.
Alarm
Fan-flt
Possible
reason
Functionality of the device internal cooling fan abnormal
Measure
Check the fan when inverter is voltage-free
Remark
-
Alarm
Branch breaker flt
Possible
reason
Circuit breaker of the branch on the DC side is abnormal and this branch cannot
work normally
Measure
Check the abnormal circuit breaker when inverter is voltage-free
Remark
Before device stops, the non-abnormal branches can work normally and inverter
can operate in grid-connection normally
Alarm
DC Sensor-err
Possible
reason
Inverter DC sensor abnormal
Measure
Check and service the DC sensor when inverter is voltage-free
Remark
-
Alarm
Anti-PID power flt
Possible
reason
After the anti-PID function is enabled, the panel positive resistance to the ground
is low due to customer's reason; or the power supply of the PID function module
is abnormal
Measure
Check the PID power supply when inverter is voltage-free
Remark