53
Fault name
Triggering
condition
Recovery
condition
Corrective measures
AC Over-
frequency
The grid voltage is
higher than 50% of
the rated voltage,
the grid frequency
is higher than the
corresponding
protection value of
level 1~5 for longer
than the over-
frequency
protection set
duration. In off-grid
mode: Enable the
AC over-frequency
function only after
the output voltage
is stable. The
protection is as the
same as that of grid
connection.
In grid-
connected
mode: The
frequency is
lower than
the over-
frequency
recovery
value for
longer than
the set grid
recovery
duration. In
off-grid
mode: The
fault will be
automaticall-
y cleared
30s after
protective
shutdown.
Generally, the machine will
reconnect to the grid when the grid
frequency returns to normal.
1. Measure the actual grid
frequency. If the grid voltage is
higher than the set value, please
contact the power company.
2. Check whether the app protection
parameters are correctly set.
3. If the fault is not caused by the
foregoing reasons and still exists,
please contact SUNGROW.
Islanding
Protection
In grid-connected
mode, LVRT is not
enabled, and the
AC voltage is lower
than 55V for
500ms; LVRT is
enabled, and the
AC voltage is lower
than 200V for
longer than the
maximum LVRT set
duration.
The AC
voltage is
higher than
220 V for
10s.
1. Check whether the grid power
supply is normal.
2. Check whether the AC cable is
firmly in place.
3. Check whether the AC cable is
connected to the correct terminal.
4. Check whether the AC circuit
breaker is connected.
5. If the fault is not caused by the
foregoing reasons and still exists,
please contact SUNGROW.
Operation & Maintenance Instruction
