Emerson Liebert GXT3 Series, User Manual

Troubleshooting

33

When reporting a UPS issue to Emerson, include the UPS model and serial number. These are on the 

top panel of the Liebert GXT3.

Fault and Bypass indicators and 

diagnostic B indicator are 

illuminated

UPS internal DC bus overvoltage

UPS requires service. Contact your local dealer, 

Emerson representative or Emerson Channel 

Support.

Fault and Bypass indicators and 

diagnostic C indicator are 

illuminated

UPS DC/DC fault

UPS requires service. Contact your local dealer, 

Emerson representative or Emerson Channel 

Support

Fault indicator and diagnostic D 

indicator are illuminated

UPS PFC (Power Factor Correction 

Circuit) fault

UPS requires service. Contact your local dealer, 

Emerson representative or the Emerson 

Channel Support

Fault and Bypass indicators and 

diagnostic E indicator are 

illuminated

UPS inverter fault

UPS requires service. Contact your local dealer, 

Emerson representative or Emerson Channel 

Support

Fault indicator and diagnostic A 

and C indicators are illuminated

UPS failed the battery test

Replace batteries. Contact your local dealer, 

Emerson representative or Emerson Channel 

Support

Fault and Bypass indicators and 

diagnostic C and E indicators 

are illuminated

UPS shut down by a command from 

the communications port(s)

Your UPS has received a signal or command 

from the attached computer. If this was 

inadvertent, ensure the communication cable 

used is correct for your system. For assistance, 

contact your local dealer, Emerson 

representative or Emerson Channel Support

Fault indicator and diagnostic A 

and B indicators are illuminated

UPS Failure (Includes Dual Fan 

failure, single fan failure under certain 

condition and Battery Charger 

Failure) and continuous alarm

Ensure fan is not blocked up. If the fault is not 

removed, contact your local dealer, Emerson 

representative or Emerson Channel Support

AC input indicator is flashing

UPS detected a line-to-neutral 

reversal or a loss of proper grounding 

for UPS; continuous horn and UPS 

cannot start up in standby status. 

This is active only when power is first 

applied to the input. Once the UPS is 

running, the AC input indictor will 

flash, unless the input wiring is 

correctly changed

Contact a qualified electrician to verify site wiring

Battery indicator is flashing

Battery source is not available; 

continuous horn

Check battery connections, completely power 

down and restart UPS.

NOTE: If the battery circuit opens while the UPS 

is running, it will be detected when the next 

battery test is performed

Bypass indicator is flashing

Because the voltage or frequency is 

outside acceptable limits, the bypass 

is disabled

The AC input powers the PFC input and serves 

as the bypass source. If the AC is present but 

the voltage or frequency exceeds the acceptable 

range for safe operation with a load, the bypass 

will be disabled and this indicator will flash, 

indicating that the bypass is unavailable

Table 9

 Troubleshooting

 (continued)

Problem

Cause

Solution