The mains switch is ON. The 
LCD does not display 
anything. The system does 
not perform self
The input power supply 
is not connected.
The input voltage 
exceeds the limit.
Check the input power cable connection.
Use a 
multimeter to check that the UPS 
input voltage meets specifications.
The mains is normal, but the 
AC input indicator is off. The 
UPS runs in battery mode.
The mains switch is OFF.
The input power cable is 
not securely connected.
Turn on the mains switch.
Check the input power cable connection.
The UPS does not report 
faults, but has no output 
voltage.
The output power cable 
is not securely 
connected.
Check the output power cable connection.
The UPS does not start after 
you press       . 
is not pressed long 
enough. 
Overload occurs.
Press        for more than 5 seconds until 
you hear a beep sound.
Disconnect all loads, and restart the UPS.
The Mains indicator is off.
The mains voltage or 
frequency exceeds the 
UPS input range.
multimeter to check that the input 
voltage and frequency meet specifications.
The battery discharge time is 
much less than the standard 
time.
Batteries are not fully 
charged.
The battery performance 
deteriorates.
Charge batteries for more than 8 hours 
when the mains is normal. Test the 
discharge time again.
Contact local 
Abnormal noises or smell is 
generated in the UPS 
cabinet.
Shut down the UPS immediately and cut 
off the input power supply. Contact local 
Huawei
The battery indicator is 
blinking yellow. The buzzer 
buzzes 1 second and then 
stops 1 second. The battery 
capacity is insufficient. The 
UPS is shutting down.
The remaining battery 
capacity is insufficient. 
The UPS is shutting 
down, and the loads are 
powering off.
Save load data immediately and power 
off critical loads.
Connect UPS input terminals to the 
backup AC power supply.