Powerware 9150 - Manual (Page 46)

Operation
42 Powerware ® 9150 User’s Guide
:
www.powerware.com
The Powerware 9150 can operate in Normal, Bypass, or Battery Mode.
The UPS automatically switches between these modes as required, and
the UPS front panel indicates the current mode of operation.
Normal Mode
When the UPS is in Normal Mode, the UPS ON and LINE ON indicators
illuminate. The LOAD indicator(s) display percentage of UPS load
capacity being used by the protected equipment.
Bypass Mode
The UPS switches to Bypass Mode in the event of an overload condition,
overtemp condition, or UPS failure. When the unit switches to Bypass, a
monotone alarm sounds and the BYPASSED indicator illuminates,
indicating that the load is powered by utility power. However, utility
power continues to be passively filtered by the UPS.
Battery Mode
Battery Mode is automatically initiated if a utility failure occurs or if
utility power does not meet preset parameters. The UPS switches to
battery (DC) power, providing power to support the load.
When the unit switches to Battery Mode, an alarm beeps for five seconds
and the ON BATTERY indicator illuminates, indicating a power outage.
The UPS remains in Battery Mode until the utility power returns or until
the battery can no longer support the inverter operation.
When the battery can no longer support inverter operation, an audible
alarm indicates that approximately five minutes of backup time remains.
The time remaining is variable and depends upon battery capacity and
loading on the unit. If a power failure outlasts the backup time, the UPS
shuts down in order to prevent a total discharge of the battery. When
utility is restored, the UPS starts automatically, providing power to the
critical load and charging the battery bank.