Huawei SUN2000 Series User Manual page 114

SUN2000-(8KTL-20KTL)-M2
User Manual
E
Locating Insulation Resistance Faults
If the ground resistance of a PV string connected to a solar inverter is too low, the
solar inverter generates a Low Insulation Resistance alarm.
The possible causes are as follows:
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To locate the fault, connect each PV strings to a solar inverter, power on and
check the solar inverter, and locate the fault based on the alarm information
reported by the FusionSolar app. If a system is not configured with any optimizer,
skip the corresponding operations. Perform the following steps to locate an
insulation resistance fault.
If two or more ground insulation faults occur in a single PV string, the following
method cannot locate the fault. You need to check the PV modules one by one.
Step 1 The AC power supply is connected, and set the DC switch at the bottom of the
solar inverter to OFF. If the solar inverter connects to batteries, wait for 1 minute,
and turn off the the battery switch and then the auxiliary power switch of the
battery.
Step 2 Connect each PV string to the solar inverter and set the DC switch to ON. If the
solar inverter status is Shutdown: Command, choose Device Commissioning >
Maintenance > Inverter ON/OFF on the app and send a startup command.
Step 3 Log in to the FusionSolar app and choose My > Device Commissioning. On the
Device Commissioning screen, connect and log in to the solar inverter, and access
the Alarm management screen. Check whether the Low Insulation Resistance
alarm is reported.
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Issue 01 (2020-07-02)
A short circuit occurs between the PV array and the ground.
The ambient air of the PV array is damp and the insulation between the PV
array and the ground is poor.
NO TICE
If the Low Insulation Resistance alarm is not reported one minute after the
DC is supplied, choose Device Commissioning > Maintenance > Inverter
ON/OFF on the app and send a shutdown command. Set the DC switch to
OFF and go to Step 2
check.
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E Locating Insulation Resistance Faults
to connect another PV string to the solar inverter for a
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