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RT33020/25/30KE User Manual
Chapter 1 Product Introduction
Main Input
Manual Bypass
Battery
Bypass
Input
Output
Switch
Rectifier/
Discharger
Inverter
Charger
Load
Fig.1-5 Maintenance mode operation diagram
Danger
During Maintenance mode, dangerous voltages are present on the terminal of input, output
and neutral, even with all the modules and the LCD turned off.
1.2.5 ECO Mode
To improve system efficiency, UPS rack system works in Bypass mode at normal time,
and inverter is standby. When the utility fails, the UPS transfers to Battery Mode and the
inverter provide powers to the loads.
Rectifier
AC/DC
Inverter
DC/AC
Charger
DC/DC
Bypass Input
Battery
Load
Static Switch
Main Input
Fig.1-6 ECO Mode operation diagram
Note
There is a short interruption time (less than 10ms) when transfer from ECO mode to battery
mode, it must be sure that the interruption has no effect on loads.
1.2.6 Auto-restart Mode
The battery may become exhausted following an extended AC mains failure. The
inverter shuts down when the battery reaches the End of Discharge Voltage (EOD). The
UPS may be programmed to “System Auto Start Mode after EOD”. The system starts
after a delay time when the AC main recovers. The mode and the delay time are
programmed by the commissioning engineer.
1.2.7 Frequency Converter Mode
By setting the UPS to Frequency Converter mode, the UPS could present a stable
