Guide Specification – 3-Phase Static Uninterruptible Power Supply
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2.3
System Operation:
The UPS shall operate as a fully automatic on-line system in the following modes:
2.3.1
Normal
IGBT Rectifier converts AC input power to DC power for the inverter and for charging the
batteries. The IGBT inverter supplies clean and stable AC power continuously to the critical
load. The UPS Inverter output shall be synchronized with the bypass AC source when the
bypass source is within the AC input voltage and frequency specifications.
2.3.2
Loss of Main Power
When Main Power is lost, the battery option shall automatically back up the inverter so there
is no interruption of AC power to the critical load.
2.3.3
Return of Main Power
The system shall recover to the operating mode in Item 1 and shall cause no disturbance to
the critical load while simultaneously recharging the backup battery.
2.3.4
Transfer to Bypass AC source
If the UPS becomes overloaded, or an internal fault is detected, the UPS controls shall
automatically transfer the critical load from the inverter output to the bypass AC source
without interruption. When the overload or internal warning condition is removed, after a
preset “hold” period the UPS will automatically re-transfer the critical load from the bypass
to the inverter output without interruption of power to the critical load.
2.3.5
Maintenance Bypass
An optional manual make-before-break maintenance bypass panel may be provided to
electrically isolate the UPS for maintenance or test without affecting load operation.
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GENERAL CONDITIONS FOR INSTALLATION
3.1
Required Output Capacity:
The UPS will be available in the following output capacities: 80, 100, 160, and 225 kVA (72, 90,
144, and 202.5 kW). Each unit shall be capable of being operated either independently or
connected in parallel for a total of up to four like-capacity units.
3.2
UPS Environment:
3.2.1
Standard Environmental Parameters
Operating Temperature
: 32° to 104°F (0° to 40°C)
Operating Humidity
: 5 - 90% (Non-condensing)
Altitude
: 7380 ft. (2250 m) (without derating)
3.2.2
Discharge Heat from UPS at full load.
80 kVA
: 11,307 Btu/Hr
100 kVA
: 14,133 Btu/Hr
160 kVA
: 19,408 Btu/Hr
225 kVA
: 27,292 Btu/Hr
