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OPM_SGS_USM_M22_M30_2US_V010.doc
User Manual
SG Series 225 & 300 UL S2
4 DESCRIPTION
4.1 BLOCK DIAGRAM AND MAIN ELEMENTS
Fig. 4.1-1 Block diagram
The
SG Series 225 & 300
system can be divided into the following main elements:
Control System
SG Series 225 & 300
is designed with microprocessor-controlled signal processing circuits.
The interface between the operator and the unit is provided by the monitoring system on the front panel.
This monitoring system consists of an active mimic diagram, a keyboard and a backlit display.
Rectifier
The standard
Rectifier
consists of a 6-pulse SCR-bridge, which converts the three-phase
Utility Voltage
into a controlled and regulated DC-voltage.
This regulated DC-voltage is used to supply power to the
Inverter
, and to provide charging power to the
Battery
.
Inverter
The
Inverter
converts the DC voltage into a three-phase AC-voltage with constant amplitude and
frequency, which is completely independent and isolated from the AC-input voltage.
Automatic Bypass
The
Automatic Bypass
consists of a static semiconductor-switch
(SSM: Static Switch Module)
, used to
provide an uninterrupted transfer of the
Load
from
Inverter to Utility
.
Back-feed Protection
All
SG Series
UPS's are equipped with an automatic system for the protection against voltage back
feeding towards
Utility
, through the
Bypass
(Applied Standard IEC 62040-1).
This protection works automatically by opening
contactor K6
and eventually
K7
, and acts in case of
internal defects of the system, or due to wrong manipulations on the
Manual Bypass Q2 (option)
.
Manual Bypass (option)
The
Manual Bypass
consists of a pair of manual switches
(Q1
and
Q2),
which removes the UPS from the
Load
for maintenance, while still supplying the
Load
with power directly from the
Utility.
Battery
The
Battery
supplies the DC power to the
Inverter
when the
Utility
is out of accepted tolerances.
