Liebert UPS System - Manual (Page 36)

Chapter 3 Electrical Assemble
30
2.Connection of serial connection cables
The monitoring board ULW2L61U2 is shown in Figure 3-8, where the locations of
RS232, RS485 and input and output contacts are marked. The user can connect
the cables with reference to this board.
communication cable RS485-
communication cable RS485+
D
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.A
fo
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. f
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or
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ve
rt er
p
ow
er
C
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. f
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or
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or
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te
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m
e rg
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m
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r em
er
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nt
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or
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om
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m
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on
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or
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or
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ad
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. f
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lo
ad
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lo
a d
N
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. f
or
g
e ne
ra
to
r p ow
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C
.C
. f
o
r ge
ne
ra
to
r
po
w
er
N
.O
. f
o
r ge
ne
ra
to
r
p ow
e r
Fig. 3-8 Monitoring Board ULW2L61U2
The length of the serial communication cables is different according to actual
conditions. The cables are not supplied with the UPS.
The communication modes of RS232, RS485, modem and SNMP can be used
together, but only one mode can be used at any time.
1) RS232 Connection
The J20 is the RS232 communication port. One end of the communication cables
should be connected to J20 and the other end should be connected to background
monitoring equipment. The meaning of each pin is shown in Figure 3-9.
Pin 2：receiving Pin 3：Transmitting Pin 5：Ground Other pins：Void
Fig. 3-9 RS232 Serial Port