Delta Ultron DPM Series, User Manual

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3 Operation Modes
3.2.6 On-Line Mode_ Dual Input_ Parallel Units
In On-Line mode (parallel), the total loads will be equally shared by 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
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by bypass power. During On-Line mode (parallel), each UPS’s tri-color LED illuminates
green and each UPS’s LCD shows the text '
AC ' in the lower right corner. Please refer to
Figure 3-18 for the path of electrical power through the parallel UPSs in On-Line mode.
MAIN
Power Module 1
Power Module 2
Power Module...
Q1
Inverter
Converter
Rectifier
Static Switch
Q5
(ON)
Q4
MAIN
Power Module 1
Power Module 2
Power Module...
Q1
Q2
Q2
Inverter
Converter
Rectifier
Static Switch
Q5
(ON)
Q4
UPS 1
UPS 2
LOAD
BYPA.
Q3
BYPA.
Q3
Static Switch
(OFF)
Static Switch
(OFF)
(Figure 3-18: On-Line Mode Diagram_ Dual Input Parallel Units)