18 Chapter 2 Installation
Liebert ITA 16kVA/20kVA User Manual
Note
1. It is prohibited to reverse the positive pole and negative pole of the battery.
2. Before replacing the battery module and connecting the battery cables, ensure that the UPS system is in maintenance mode.
3. The length of the battery cable option is 1.5m. If you need more length cables, please consult the dealer. It is recommended that
the battery cable be shorter than 3m. Otherwise, the UPS cannot operate normally.
2.7 Connecting Communication Cables
Communication cables include: dry contact communication cable, USB communication cable and SNMP card
communication cable.
All the communication cables are the dual insulation cables which must be separated from the power cables for
wiring. When the longest connection distance ranges from 25m to 50m, the CSA should be rangeed from 0.5mm
2
to
1.5mm
2
.
2.7.1 Connecting Dry Contact Communication Cable
The UPS provides five dry contact ports, see Figure 1-2 for specific positions. The silk screens of the five dry contact
ports are 1, 2, 3, 4, 5. The pin distribution for each dry contact port is shown in Figure 2-16, and the port description is
shown in Table 2-3.
SAL
AR
M
GN
D
On_b
atter
y
GN
D
On
_bap
as
s
GN
D
E
po_N
C
+1
2
V
+12V
Ep
o
_
IN
+1
2
V
BF
P_
o
BF
P_
c
BF
P_
s
Dry contact port 1 Dry contact port 2
Dry contact port 3
Dry contact port 4
Dry contact port 5
Figure 2-16 Pin distribution of dry contact ports
Table 2-3 Description of the dry contact ports
Silk
screen
Port name
Pin NO.
Pin name
Meaning
1.1
S_ALARM
The signal level is 12V, when the system alarms
1
Output port of alarm
1.2 GND
GND
2.1 ON_BATTERY
The signal level is 12V, when the system runs in battery
inversion mode
2
Output port of battery
status
2.2 GND
GND
3.1
ON_BYPASS
The level is 12V, when the system runs in bypass mode
3
Output port of bypass
status
3.2 GND
GND
4.1
EPO_NC
EPO activated, when opened to 4.2
4.2
+12V
EPO activated, when opened to 4.1
4.3
+12V
EPO activated, when shorted to 4.4
4
Input port of remote
EPO *
4.4
EPO_IN
EPO activated, when shorted to 4.3
5.1 BFP_O
Bypass reflected protection relay (normally open), the bypass
SCR will close when short circuit appears
5.2
BFP_S
The middle point of the bypass reflected protection relay
5
Output port of bypass
reflected
5.3 BFP_C
Bypass reflected protection relay (normally open), the bypass
SCR will open when short circuit appears
Note*: Pin1 and pin2, or pin3 and pin4 of the dry contact port 4 reserves the corresponding terminals for configuring the EPO
function. The external EPO device also needs the shielded cable to connect to the normally open/close remote EPO switch
between the two terminals. If not necessary, you should disconnect pin3 and pin4 of the dry contact port 4, or short pin1 and pin2
of the dry contact port 4. Pin1 and pin2 of the dry contact port 4 have been shorted before delivery
