Emerson GXT3 Power Supply User Manual


 
Product Description
9
Battery Charger
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.
DC-to-DC Converter
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.
Battery
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.
Dynamic Bypass
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.
1.5 Operating Mode
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
Indicators.
1.5.1 Utility (AC) Mode
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.
1.5.2 Manual Bypass Mode
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.
NOTICE
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.