Understanding Ups Operation; Figure 7-1. Main Elements Of The Ups System - Eaton POWERWARE 9315 Installation And Operation Manual

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

Understanding UPS Operation

The Powerware 9315 is a continuous duty, solid-state UPS that supports the
following equipment: process control, data processing, telecommunications/PBX,
research, and medical. The Powerware 9315 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 7-1 shows the main elements of the UPS system.
Input/Rectifier
Input
Transformer
Input
Breaker
Rectifier/
CB1
Charger
Input
Filter
Module Bypass Cabinet (MBC)
The emergency bypass consists of a static switch, a wraparound bypass breaker
(CB4) and a Backfeed Protection Breaker (FBP). The FBP is located in series with the
static switch and opens so that the UPS cannot backfeed the bypass source.
For manual transfers to bypass, the static switch is not used. During the transfer, CB4
is closed and verified and then inverter output breaker CB3 is opened. For transfers of
the load from bypass to the UPS, CB3 is closed and verified and then CB4 is opened.
The static switch is armed and ready during both types of transfers.
®
9315 UPS (500–750 kVA) Installation and Operation Manual
Battery
Breaker
CB2
F30
F31
Inverter
Power
Processing Unit
Digital
Metering
Static
Switch
Backfeed
Protection
Breaker FBP
Bypass
Breaker
CB4

Figure 7-1. Main Elements of the UPS System

S
164201691 Rev 1 www.powerware.com
Battery String
Output/Inverter
Output
Transformer
AC Output
to Critical
Output Load
Breaker
CB3
Input
Filter
7-1