Emerson 208V Manuel D’Utilisation

The battery charger utilizes energy from the utility power and precisely regulates it to continuously 

float charge the batteries. The batteries are being charged whenever the Liebert

®

 GXT3

™

 is plugged 

in, even when the UPS is not turned On.

The DC-to-DC converter raises the DC voltage from the battery to the optimum operating voltage for 

the inverter. This allows the inverter to operate continuously at its optimum efficiency and voltage, 

thus increasing reliability.

The Liebert GXT3 uses valve-regulated, nonspillable, lead acid batteries. To maintain battery design 

life, operate the Liebert GXT3 in an ambient temperature of 32°F to 77°F (0°C to 25°C).
Optional external battery cabinets are available to extend battery run times.

The Liebert GXT3 provides an alternate path for utility power to the connected loads in the unlikely 

event of a UPS malfunction. Should the Liebert GXT3 have an overload, overtemperature or UPS 

failure condition, the UPS automatically transfers the connected loads to bypass.

The UPS operation modes include: Utility (AC) mode, bypass mode, battery mode, battery recharge 

mode and frequency converter mode.
For the descriptions of indicators and control buttons in this section, refer to 3.0 - Controls and 

During Utility (AC) Mode, utility power provides energy to the Liebert GXT3. The filters, PFC circuit 

and the inverter process this power to provide computer-grade power to connected loads. Meanwhile, 

the UPS maintains the batteries in a fully charged state.

Manual Bypass Mode occurs when the Standby/Manual bypass button is pressed and held for about 

2 seconds while the Liebert GXT3 is in Utility (AC) Mode. Bypass operation is indicated by an audible 

alarm and illuminated amber bypass indicator (If other indicators are illuminated, refer to 7.0 - 

Troubleshooting). During manual bypass mode, utility power bypasses the inverter and provides 

energy to the connected load.

Turning Off the UPS in bypass mode will result in loss of output power and dropped loads.

NOTE
The bypass power path does not protect the connected loads from disturbances on the utility.