Liebert UPS System user manual No.1 Fault description Reason Actions to be taken

Chapter 7

Troubleshooting

No.1

Fault description

Reason

Actions to be taken

Bypass voltage or frequency is out

15

Bypass

of normal range and inverter output

Check the bypass voltage and frequency

unsynchronized

is not synchronized with the bypass

output.

Bypass

voltage

or

frequency

16

Bypass ratings exceed

exceeds the normal range and the

Check the bypass voltage and frequency

the normal range

bypass will not power the load

anymore.

17

Bypass SCR fails

Bypass SCR is damaged

Notify the service dept for repairing

Bypass over current

If the over current time exceeds the

Check the load, if it is normal, then restart

18

timeout

limit, the UPS may shut down the

the UPS

bypass and the inverter.

Shutdown due to

When the overload delay time is due

Repair the bypass and reduce the load,

19

in inverter mode, if at this time the

and then restart the UPS. Note: Don’t let

bypass fault

bypass has fault, then the inverter is

the UPS in over load state for a long time.

shutdown.

The battery life is reduced due to

Notify the service dept for replacing the

20

Battery

needs to

be

aging, which may endanger the

battery and set the battery model and

replaced

normal operation of UPS. Warn the

parameters through software.

user that the battery is abnormal and

needs to be replaced.

21

No battery

Batteries are not connected.

Check

the

battery

and

the wiring of

batteries

The battery discharges to pre-alarm

22

Pre-alarm for end of

point (the battery capacity is

Shut down the load in time

battery discharging

inadequate), the system may shut

down after a few minutes

23

battery over

battery temperature is too high

Check

the

battery

temperature and

temperature

ventilation

24

Battery

contactor

is

Battery contactor fails

Notify the service dept for repairing

abnormal

25

battery

self-test

is

The battery condition for self-test is

Start the self test after the conditions can

disabled

not satisfied

meet the requirements

26

Battery

is connected

Battery is connected reverse

Notify the UPS service engineer to

reverse

connect the battery again

27

Bypass phase rotation

Bypass phase rotation is reverse

Notify the UPS service engineer to

is reverse

change the bypass phase rotation

28

Rectifier fails

Rectifier

is abnormal

and has

Notify the service dept for repairing

serious fault

29

Rectifier heatsink over

Rectifier heatsink temperature is too

The UPS

can recover

automatically.

temperature

high

Check the environment and ventilation

84