Huawei SUN2000 Series User Manual page 98

SUN2000-(29.9KTL, 33KTL-A, 36KTL, 42KTL)
User Manual
Alarm ID Alarm
Name
305 Abnormal
Grid
Frequency
313 Low
Insulation
Resistance
Issue 11 (2019-06-08)
Alarm Possible Cause
Severity
Major  Cause ID = 2
The actual grid frequency is
higher than the standard
requirement for the local
power grid.
 Cause ID = 4
The actual grid frequency is
lower than the standard
requirement for the local
power grid.
 Cause ID = 5
The actual change rate of
the grid frequency does not
meet the standard
requirement for the local
power grid.
Major Cause ID = 1
 A short circuit occurs
between the PV string and
the PGND cable.
 The PV string is installed in
a moist environment for a
long time.
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Suggestion
Cause ID = 2/4
1. If the alarm occurs accidentally,
the power grid may be abnormal
temporarily. The SUN2000
automatically recovers after
detecting that the power grid
becomes normal.
2. If the alarm occurs frequently,
check whether the grid frequency
is within the acceptable range. If
no, contact the local power
operator. If yes, log in to the
SUN2000 app, SmartLogger, or
NMS to modify the grid
overfrequency and
underfrequency protection
thresholds with the consent of the
local power operator.
Cause ID = 5
1. If the alarm occurs accidentally,
the power grid may be abnormal
temporarily. The SUN2000
automatically recovers after
detecting that the power grid
becomes normal.
2. If the alarm occurs frequently,
check whether the grid frequency
is within the acceptable range. If
no, contact the local power
operator.
1. Check the impedance between
the PV string and the PGND
cable. If a short circuit occurs,
rectify the fault.
2. If you are sure that the impedance
is less than the default value in a
cloudy or rainy environment, log
in to the SUN2000 app,
SmartLogger, or NMS and set
Insulation resistance
protection.
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