Powerware 5075 kVA - Manual (Page 48)

40 Powerware BPIII Harsh Environment UPS 50--75 kV Installation and Operation
164291261 Rev. F 111503
Looking Inside the UPS
The Powerware BPIII HE is a continuous duty, solid-state UPS that supports the
following equipment: process control, data processing, and
telecommunications/PBX. The Powerware BPIII HE maintains power to the critical
loads during commercial electrical power brownout, blackout, overvoltage,
undervoltage, and out-of-tolerance frequency conditions.
In this manual, the power required by your equipment is called the critical load. The
UPS supplies the critical load with conditioned power that is synchronized with your
utility power. Figure 17 shows the main elements of the UPS.
OUTPUT
DIGITAL
BYPASS
AC INPUT TO AC OUTPUT
INPUT
RECTIFIER/ INVERTER
FILTER
CONTACTOR
METERING
CONTACTOR
RECTIFIER/ TO CRITICAL
CHARGER
STATIC
SWITCH
CHARGER
UPS CABINET
LOAD
TRANSFORMER
OUTPUT
POWER PROCESSING UNIT
DC/DC
CONVERTER
DC INPUT
INPUT
ISOLATION
TRANSFORMER
INPUT
BYPASS
BREAKER
(BIB)
AC INPUT
TO BYPASS
ISOLATION
MAINTENANCE
SWITCH
(MIS)
BYPASS
MAINTENANCE
BREAKER
(MBP)
Figure 17. Main Elements of the UPS System
If utility power is interrupted or falls outside the parameters specified in the Product
Specifications section of Chapter 16, the UPS uses a backup supply to sustain
power to the critical load for a specified period of time or until the utility power
returns. For extended power outages, the backup supply 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 operation of the UPS system is described in greater detail in the following
paragraphs. The Product Specifications section of Chapter 16 outlines the storage
and operating specifications for the UPS.