Delta DPS-400K - Page 61

5-15
5
Installation and Wiring
WARNING:
1. When UPSs are paralleled, the length of each unit’s input cables plus
output cables must be the same. This ensures that the parallel UPSs can
equally share the critical loads in bypass mode.
2. Only UPSs with the same capacity, voltage and frequency can be paralleled;
otherwise, parallel functions will fail.
(Figure 5-14: Parallel Units Single Input Wiring Diagram)
UPS 1
UPS 2
UPS 8
I/P
LOAD
Main Input
Main Input
Main Input
Output
Output
Output
Parallel Port
Parallel Port
Parallel Port
Parallel Port
Parallel Cable
3Ø4W 3Ø4W
Parallel Cable
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Dual Input (Parallel Units)
When there are two AC power sources, parallel units’ wiring procedures are as follows.
1
Follow 6LQJOH,QSXW'XDO,QSXW0RGL¿FDWLRQ to modify the parallel UPSs
into dual input.
2
Follow the procedures
1
~
6
stated in the section of Single Input (Single
Unit).