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3 Operation
Vertiv™ | Liebert® PSI5 120V Input / 120V Output & 208V lnput / 208V Output Installer/User Guide
3 Operation
3.1 Modes of Operation
3.1.1 Off Mode
The UPS input is plugged into a stable, nominal source, but the outlets are turned off. The internal batteries
are charging.
3.1.2 On/Normal Mode
The UPS input is plugged into a stable, nominal source, and the outlets are turned on. The internal
batteries are charging.
3.1.3 On/Automatic Voltage Regulation (AVR)/Boost Mode
The UPS input is plugged in, but the voltage source is abnormally low (brown-out). The UPS automatically
corrects the low voltage and allows the outlets to be on with the normal, expected voltage. The internal
batteries are charging.
3.1.4 On/Automatic Voltage Regulation (AVR)/Buck Mode
The UPS input is plugged in, but the voltage source is abnormally high. The UPS automatically corrects the
high voltage and allows the outlets to be on with the normal, expected voltage. The internal batteries are
charging.
3.1.5 On/Battery Mode
The UPS input is not plugged in or the voltage source has become extremely low or high and unusable.
The UPS automatically switches to the internal battery to provide normal, usable voltage to the outlets.
3.1.6 Fault Mode
An error or fault condition has occurred. The outlets are shut off.
3.1.7 Battery Self-Test Mode
The UPS enters a cycle of approximately 10 seconds during which it tests the internal battery. The outlets
are still temporarily powered by the internal battery. Self-test mode occurs at the following instances:
•
At startup when turning the UPS on.
•
Automatically every 8 weeks as a self-check.
•
Manually by pressing and holding the ON/Mute button for 3 seconds when the unit is on.