LG ACP IV Install/Owner’s Manual page 9

Check points during the ACP
IV installation
• The number of PI485 connected to one RS-
485 communication line
ACP IV provides 4 RS-485 ports for indoor
unit connection. (CH 1~4)
Up to 16 PI485 for outdoor unit can be con-
nected to one RS-485 port, and up to 31
PI485 for SINGLE/ERV can be connected.
• The number of the indoor units that can be
connected to one ACP IV.
One ACP IV can be connected up to 256
indoor units. With ACS I/O interlocking, you
can connect 128 indoor units and 16 I/O
modules. And with chiller interlocking, you
can connect 128 indoor units and 10 chiller
units. To one RS-485 port, all of 256 indoor
units, which is the maximum number that
can be connected to the ACP IV, may be
connected. But, to improve the communica-
tion performance of RS-485, it is recom-
mended to be divided and connected to 4
ports.
The maximum quantity of connected indoor
unit is different depending on the quantity of
connected I/O modules.
Please refer to following information related
to product connection quantity.
Quantity of
Device
256
128
* Devices: Indoor units, ERV, DI/DOs,
DOKITs, AWHPs, AHUs
• RS-485 communication cable connection
There is a polarity in RS-485 communication
cable connection, so be careful not to
reverse the connection of the two cables.
Do not let the length of RS-485 communica-
tion cable exceed total of 1 km.
RS-485 communication cable must be con-
nected with BUS type.
• IP address of the ACP IV
IP address of the ACP IV, address of
Gateway, and Net mask must be requested
to the person in charge of the network of
the corresponding site.
!
RS-485 Connection of the ERV equipment
To connect ERV equipment, it is recom-
mended to use the ports other than RS-
485 communication ports which are con-
nected to air conditioners.
16
Quantity of I/O
Module
INSTALLING ACP IV
CAUTION
Quantity of
I/O Module
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
9
Quantity of
Device
256
248
240
232
224
216
208
200
192
184
176
168
160
152
144
136
128