Emerson Liebert NX 480V - Manual (Page 35)

Options
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Figure 15 Load Bus Synchronization cable connection with multi-module systems
The LBS function is activated with configuration software; when the LBS takes effect, the graphic
LCD will display “LBS active.”
4.2 Configuring Parallel System Operation
4.2.1 General
The Liebert NX uses intelligent and reliable decentralized technology to achieve parallel operation of
two or more modules.
The parallel system is used to:
• Increase the reliability of the system to ensure adequate power supply to the critical load con-
nected.
• Increase serviceability and allow the execution of maintenance operations and repairs without
affecting the ordinary operating conditions of the system (depending on the redundancy level).
4.2.2 Features of Parallel System
• The controls for parallel UPS module operation are standard in the Liebert NX, and the configu-
ration can be set up by changing the settings in configuration software.
• It is easy to install the parallel cables in a ring, providing high reliability and redundancy. And
the intelligent paralleling logic provides the user with maximum flexibility. For example, shut-
ting down or starting up the UPS modules in the parallel system can be done in any sequence. If
an overload transfer occurs, the whole system can recover automatically from bypass mode after
the overload is cleared.
• The total load of the parallel system can be queried from each module’s liquid crystal display
screen.
UPS
X1-1 X1-2
X2-2 X2-1
Parallel Board
X4
X3 P5
P3
P4
P1 P2
X1-1 X1-2
X2-2 X2-1
Parallel Board
X4
X3 P5
P3
P4
P1 P2
8
X1-1 X1-2
X2-2 X2-1
Parallel Board
X4
X3 P5
P3
P4
P
1
P2
X1-1 X1-2
X2-2 X2-1
Parallel Board
X4
X3 P5
P3
P4
P
1
P2
8
UPS
B
Parallel System I Parallel System II
DBS Cable
A