MGE UPS Systems 40-75KVA - Manual (Page 14)

Galaxy 4000
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1.2 Major Components
Rectifier Converts AC input voltage to DC voltage. The rectifier uses IGBT (Insulated G a t e
Bipolar Transistor) power transistors and a Pulse Width Modulated (PWM)
technique to provide input power factor correction and to minimize any harmonic
reflected onto the input power lines.
Inverter Converts DC voltage from the rectifier or from the batteries into AC output voltage
to maintain the attached load. This module uses the IGBT technology to provide
digital power quality.
Static Switch Automatically supplies the attached load from the bypass source when the inverter
is off.
Battery System Stores energy for utilization by the inverter and attached load in the event that utility
AC power is lost or is of unacceptable quality.
1.3 Single Line Diagram
During normal operation, the utility power (Main input) is supplied to the UPS rectifier. The rectifier converts the AC
power to DC that is supplied to the inverter. The inverter converts the DC voltage to three-phase regulated AC
voltage, which is supplied to the attached load.
During power failure conditions, the inverter is supplied by the stored energy in the battery system, and the load is
powered continuously with no interruption.
The Galaxy 4000 UPS is designed for internal operation of 208VAC input and output. External batteries, and an
output distribution panel may be contained in auxiliary cabinets similar in design to the Galaxy 4000 cabinet.
Batteries or external maintenance bypass circuit breakers may also be contained in third party cabinets or wall
mounted units.
Figure 1-2: Galaxy 4000 UPS System – Single Line Diagram.
Introduction
BYPASS
INPUT
TB3
A
B
C
A
B
C
N
G
INPUT
STATIC
SWITCH
INPUT
FUSES Q1
Q4S
BATTERY
STATIC SWITCH
BATTERY
CHARGER
KB (OPTIONAL)
CONTROL CONNECTIONS
(SEE UPS INSTALLATION DWG)
TB4
REPO ON MBS
SUPPLIED BY MGE &
CON NECTED BY CUSTOMER
(ADJACENT VERSION)
SUPPLIED & CONNECTED
BY CUSTOMER
(STAND ALONE VERSION)
TO
CRITICAL
LOAD
OUTPUT
TB2
Q3BP (OPTIONAL)
7 8 9 10
A
B
C
N
G
Q5N
PFC
BOOST
RECTIFIER INVERTER
OUTPUT
STATIC
SWITCH
BYPASS
STATIC
SWITCH
UPS
MAIN
INPUT
TB1
OPTIONAL
BYPASS
INPUT
208YVAC
MAIN
INPUT
208YVAC
KA
DISTRIBUTION
BATTERY
42 POLE
PANELBOARD
OUTPUT
CB
(OPTIONAL)
SUPPLIED BY MGE &
CONNECTED BY CUSTOMER
CB1 CB1
TB4
CB1 CB1