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User Manual 10H52188UM60 - Rev. 2 - 09/2012
Parallel UPS Installation And Commissioning
Liebert NXC
4.3.2
Connecting Parallel Cables
In case of parallel system the optional cable is supplied. The parallel cables form a ring connection through the parallel ports
on the UPS rear panel. The cable connection schematic diagram of 3 + 1 parallel system is shown in Figure 4-2. The first port
on the left is DB9 male port (needle shape), and the second port on the left is DB9 female port (hole shape).
UPS 1
bC
mC
bB
mB
bA
mA
bN
mN
oN oN oA oB oC
PE PE
UPS 2
bC
mC
bB
mB
bA
mA
bN
mN
oN oN oA oB oC
PE PE
UPS 3
bC
mC
bB
mB
bA
mA
bN
mN
oN oN oA oB oC
PE PE
UPS 4
bC
mC
bB
mB
bA
mA
bN
mN
oN oN oA oB oC
PE PE
DB9 male port
DB9 female port
Figure 4-2 Cable connection schematic diagram of 3 + 1 parallel system
Note
1. The Emerson parallel cables must be used for the parallel system.
2. The parallel communication fault occurs when carrying out the parallel commissioning, check whether the connection of the parallel
cables is correct, and whether the pin1~ pin9 are connected.
Setting parallel addresses
The parallel addresses for all UPS in parallel system should be set. The parallel addresses can be set through the DIP switch on
the UPS front panel (see Figure 1-2). Remove the DIP switch cover, and set the DIP switch according to Table 4-1.
Table 4-1 DIP switch settings
Parallel addresses
Parallel 1#
Parallel 2#
Parallel 3#
Parallel 4#
DIP switch position
ON
1
2
3
4
5
OFF
ON
1
2
3
4
5
OFF
ON
1
2
3
4
5
OFF
ON
1
2
3
4
5
OFF
