Normal Mode - Powerware 9330 Installation And Operation Manual

6.2.1

Normal Mode

Figure 6---2 shows the path of electrical power through the UPS system when the
UPS is operating in Normal mode.
MAINTENANCE
BYPASS SWITCH
CB1 K1
Breakers Contactors
Figure 6 ---2. Path of Current Through the UPS in Normal Mode
During normal UPS operation, power for the system is derived from a utility input
source through the input breaker CB1 and contactor K1. "Normal" appears on the
front panel and indicates the incoming power is within voltage and frequency
acceptance windows. Three phase AC input power is converted to DC using a
full---wave, six---pulse, solid---state rectifier block which supplies unregulated DC
voltage to a boost converter which in turn supplies a higher and regulated DC
voltage to the inverter. The battery is not charged directly from the unregulated
rectifier. Instead, a separate battery charger is used to maintain the proper charge
level on the battery during normal operation.
6--4
NORMAL MODE
STATIC
K5
SWITCH
RECTIFIER
CHARGER
Closed
Open
BATTERY
BOOST
CONVERTER
K2
CB2
Powerware 9330 (10 kVA- -40 kVA) Installation and Operation
INVERTER
K3
MAINTENANCE
BYPASS SWITCH
Main Power Flow
Trickle Current
Energized
De- -Energized
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