Huawei Proprietary and Confidential                                     
Copyright © Huawei Technologies Co., Ltd. 
 
Electrical 
Grounding 
Fault 
 
The neutral wire or PGND 
cable is not connected to 
the SUN2000. 
 
The isolation transformer is 
not connected to the 
SUN2000 at the output side 
when the PV strings are 
grounded. 
a.  Check that the neutral wire and 
PGND cable are properly 
connected. 
b.  Check that an isolation 
transformer is connected to the 
SUN2000 at the output side when 
the PV strings are grounded. 
An unrecoverable fault has 
occurred on a circuit inside the 
SUN2000. 
Flip the DC SWITCH on the 
SUN2000 to OFF, wait 5 minutes, 
and flip the DC SWITCH to ON. 
Check whether the fault is rectified. 
If the fault persists, contact Huawei 
technical support. 
Internal 
Communic
ation Fault 
 
The communication circuit 
of the SUN2000 is 
interrupted. 
 
The communication circuit 
is damaged. 
 
The internal 
communication address is 
incorrectly set. 
a.  If the fault is caused by a short 
circuit of the communication 
circuit inside the SUN2000, the 
SUN2000 automatically reverts 
to normal operating status after 
the fault is rectified. 
b.  If the fault persists for a long 
time, contact Huawei technical 
support. 
The version of the software 
loaded during a software 
upgrade is incorrect. 
Check whether a recent software 
upgrade has been performed. If so, 
upgrade the software again to the 
correct version. 
The upgrade is incomplete. 
 
There is insufficient space 
on the flash drive. 
 
The flash drive has bad 
blocks or is faulty. 
a.  Replace the monitoring board. 
b.  If the monitoring board is built 
into the monitoring device, 
replace the monitoring device. 
 
 
If a fault cannot be rectified by the measures listed in Table 8-2, contact Huawei technical support.