GE Industrial Solutions SG Series 10 – 20 – 30 – 40 kVA Operating Manual - Manual (Page 12)

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OPM_SGS_USM_10K_40K_0US_V030.doc 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.