Understanding Ups Operation; Figure 7-1. Main Elements Of The Ups System - Eaton Powerware 9390 Installation And Operation Manual

Chapter 7
Figure
AC Input to
Rectifier/
Charger
AC Input to
EATON Powerware

Understanding UPS Operation

The Powerware 9390 UPS is a continuous-duty, solid‐state, transformerless (at 208,
380, 400, 414, and 480 Vac), three-phase, true online system that provides
conditioned and uninterruptible AC power to the UPS system's output. The UPS
supports process control, data processing, telecommunications/PBX, research, and
non-patient medical equipment. The Powerware 9390 UPS maintains power to the
critical loads during commercial electrical power brownout, blackout, overvoltage,
undervoltage, and out‐of‐tolerance frequency conditions.
The basic system consists of a rectifier, battery converter, inverter, monitoring/
operation control panel, integrated communication server, and digital signal processor
(DSP) logic.
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 7‐1 shows the main elements of the UPS system.
Input
Contactor
K1
Bypass
If utility power is interrupted or falls outside the parameters specified in Chapter 14,
"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.
®
9390 UPS (20–80 kVA) Installation and Operation Manual
Battery
Battery
Breaker
Battery
Converter
Rectifier
Power Module
Digital
Metering
Static
Switch
Backfeed
Protection
Contactor
K5
UPS Cabinet
Figure 7‐1. Main Elements of the UPS System
S
164201603 Rev 2 www.powerware.com
Output
Contactor
K3
Inverter
AC Output
to Critical
Load
7-1