Powerware 9395 UPS 10001100 kVA - Manuel (Page 105)

EATON Powerware ® 9395 UPS (1000–1100 kVA) Installation and Operation Manual S 164201764 Rev 1 www.powerware.com 6−1
Chapter 6
Understanding UPS Operation
6.1 UPS System Overview
The Powerware 9395 UPS is a continuous−duty, solid-state, transformerless (at
480 Vac), three−phase, true online system that provides conditioned and
uninterruptible AC power to the UPS system’s output and critical load.
The basic system consists of a rectifier, battery converter, inverter,
monitoring/operation control panel, integrated communication server, and digital
signal processor (DSP) logic. Figure 6-1 shows the main elements of the UPS system.
Output
Contactor
K3
Battery
Battery
Breaker
Battery
Converter
Input
Contactor
K1
AC Input to
Rectifier/
Charger
AC Input to
Bypass
Backfeed
Protection
Contactor
K5
Power Module
Inverter Rectifier
Digital
Metering
Static
Switch
AC Output
to Critical
Load
UPS Cabinet
Battery
Contactor
K2
Battery System
Input
Breaker
CB1
(optional)
Bypass Breaker (CB4)
Figure 6-1. Main Elements of the UPS System
If utility power is interrupted or falls outside the parameters specified in Chapter 10,
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 consists of a momentary−duty static switch, a wraparound
bypass breaker, and a backfeed protection contactor K5. The bypass breaker is
located in parallel with the static switch. The backfeed protection contactor is located
in series with the static switch. Bypass breaker CB4 is used for manual transfers to
bypass without using the static switch. The static switch is armed and ready during
both types of transfers.
Figure 6Table 6