Powerware 9330 Installation & Operation Manual page 82

CONTACTOR
AC INPUT TO
RECTIFIER/
CHARGER
INPUT
BREAKER
CB1
INPUT
FILTER
AC INPUT TO
BYPASS
UPS CABINET
If utility power is interrupted or falls outside the parameters specified in Chapter 15,
"Product Specifications," the UPS uses a backup battery supply to maintain power
to the critical load for a specified period of time or until the utility power returns.
For extended power outages, the UPS allows you to either transfer to an alternative
power system (such as a generator) or shut down your critical load in an orderly
manner.
The emergency bypass consist of a continuous duty static switch, and backfeed
protection contactor (K5). The backfeed protection contactor is located in series
with the static switch. For manual transfers to bypass, the static switch is also
used. The static switch is armed and ready during both types of transfers.
A wraparound Maintenance Bypass switch provides a means of isolating the UPS
Power Processsing Unit (PPU) for servicing, while still suppling power to the critical
load.
The operation of the UPS system is described in greater detail in the following
paragraphs.
7--2
BATTERY
BREAKER
CB2
BATTERY
CHARGER
INPUT
K1
RECTIFIER
DIGITAL
METERING
MAINTENANCE
BYPASS SWITCH
STATIC
SWITCH
BACKFEED
PROTECTION
CONTACTOR
K5
Figure 7 ---1. Main Elements of the UPS System
BATTERY
BATTERY
SWITCHES
DC- -DC BOOST INVERTER
CONVERTER
POWER PROCESSING UNIT
Powerware 9330 (10 kVA- -40 kVA) Installation and Operation
OUTPUT
CONTACTOR
K3
OUTPUT
FILTER
AC OUTPUT
TO CRITICAL
LOAD
164201300 Rev. N 013004