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OPM_SGS_USM_10K_40K_0US_V010.doc
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Operating
Manual
SG Series
10, 20, 30 & 40 kVA
3.2 OPERATION
MODES
3.2.1 Normal operation mode
During normal operation, the
Rectifier
converts input AC power to DC.
The DC power provides input power for the
Inverter
and charging power for the
Battery
.
The
Inverter
converts the DC power to
continuous and regulated AC power, which
supplies the critical load.
The control panel reports the
Battery
charge
status and the expected backup time with the
actual load.
Fig. 3.2.1-1 Block diagram normal operation mode
3.2.2 Utility failure operation
When the
Utility
is no longer within acceptable
tolerances, the
Battery
will provide the DC
power to the
Inverter
.
The
Inverter
will maintain continuous AC
power to the
Load
until the
Battery Voltage
reaches the lower limit of the
Inverter
operation capability.
During the discharge, the LCD screen displays
the estimated time the
Battery
can support the
critical load.
Prior to the
Battery
completely discharging,
the
"
stop operation
"
alarm (shutdown
imminent) warns the operator that the
Battery
is almost discharged and the UPS is about to
shut down.
Fig. 3.2.2-1 Block diagram Utility Failure operation
In case of parallel operation
With a parallel system for power capacity (see Section 3.3)
•
With the
Bypass Utility power available,
a low Battery warning on any unit will cause the
Load to be transferred to Utility (after a selectable time delay).
•
With
Bypass Utility power
not available, a low Battery warning on any unit will start the
“
stop operation
” timer (adjustable).
The Load will shut down at the end of the “
stop operation
” time period.
With a parallel system for redundancy (see Section 3.3)
•
When a Battery low warning occurs on a unit not necessary to support the present load, this
unit will shut down after a timeout period (selectable).
The Load is shared between the other units
•
As the warning occurs on one unit necessary to support the present load, the system starts
the "
stop operation
" timeout (selectable).
The Load will shut down at the end of the “
stop operation
” time period.