3Com Powerware Uninterruptible Power System Prestige Series - Manual (Page 54)

UPS Operation
48 Powerware ® Prestige Series Installation and Operator’s Manual for IBM Applications (3000 VA) Uncontrolled Copy
Operating Modes
After you install and apply power to the UPS, the UPS filters and
regulates incoming AC power, eliminating noise and voltage spikes, and
provides consistent power to your equipment (see Figure 12). While
power is applied to the UPS, the maintenance-free battery is
automatically kept in a fully-charged condition.
UPS Load
Outlet
Battery
Battery Cabinets
Utility
Power
Surge
Suppression
EMI/RFI Filters
Rectifier Inverter
Bypass Line
Battery Battery
Battery
Charger
Figure 12. UPS Block Diagram
Normal Mode
During Normal mode, the

indicator illuminates and the front panel
displays the percentage of UPS load capacity being used by the protected
equipment (see Figure 13).
LOAD OFF LOAD ON LOAD ON LOAD ON LOAD ON
APPROX.
81-100%
LOAD
APPROX.
61-80%
LOAD
APPROX.
41-60%
LOAD
APPROX.
0-40%
LOAD
NORMAL
UTILITY
OVERLOAD
SITE FAULT
OVERTEMP
BATTERY
SELF TEST
Figure 13. Normal Operation Indicators