Delta Modulon DPH series - Online Mode_ Single Input_ Parallel Units

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Operation Modes
3.1.9 Online Mode_ Single Input_ Parallel Units
In online mode (parallel), the total loads will be equally shared by the parallel UPSs. If one
of the parallel units fails and its load is less than the total capacity of the remaining parallel
units, the failing UPS’s output will be switched off and its load will be equally shared by
the remaining parallel units. If the failing UPS’s load is larger than the total capacity of the
remaining parallel units, all UPSs’ inverters will turn off and the total loads will be supplied
by bypass power. During online mode, each UPS’s tri-color LED illuminates green and each
UPS’s LCD shows the text ‘On-Line’ in the upper right corner. Please refer to Figure 3-11 for
the path of electrical power through the parallel UPSs in online mode.
MAIN
LOAD
MAIN
1
2
Q1 Q0 Q4
Q3
UPS
Q1 Q0 Q4
Q3
UPS
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Q5
Q5
Delta or non-Delta External Maintenance Bypass Cabinet
Batteries
Rectifier Inverter
Static Switch
Delta or non-Delta External Maintenance Bypass Cabinet
Batteries
Rectifier Inverter
Static Switch
(Figure 3-11: Online Mode Diagram_ Single Input Parallel Units)