SUN2000-(3.8KTL-11.4KTL)-USL0 
User Manual 
7 Operations on the Local FusionHome App 
Huawei Proprietary and Confidential                                     
Copyright © Huawei Technologies Co., Ltd. 
The optimizer needs to be 
unlocked before inverter 
replacement. 
The SUN2000 monitors PV 
strings at night. If 
Night-time hibernation is 
set to Enable, the 
monitoring function of the 
SUN2000 will hibernate at 
night, reducing power 
consumption.   
Set the TCP heartbeat 
interval between the 
management system and the 
inverter. If it is set to 65535, 
there is no heartbeat. If it is 
set to 0, the heartbeat 
interval is 3 minutes by 
default. 
This parameter is mainly 
used in upgrade scenarios at 
night when there is no 
power output from the PV 
strings or the dawn or dusk 
when output is unstable. 
When the grid voltage is 
abnormally low for a short 
time, the SUN2000 cannot 
disconnect from the power 
grid immediately and has to 
work for some time. This is 
called low voltage 
ride-through (LVRT). 
Threshold for triggering 
LVRT (V) 
Specifies the threshold for 
triggering LVRT. 
LVRT undervoltage 
protection shield 
Enables or disables the 
undervoltage protection 
shield during LVRT. 
LVRT reactive power comp 
factor 
During LVRT, the 
SUN2000 needs to generate 
reactive power to support 
the power grid. This 
parameter specifies the 
reactive power generated by 
the SUN2000.