12
6.3 Communication Wiring
  Use only shielded wires for the communication wiring. Any other 
type of wires may produce a signal interference that will cause the 
units to malfunction.
  Do not carry out electrical works like welding with the power on.
 
  Do not bind the refrigerant piping, power cords and communication 
wiring together. When the power  cord and communication wiring 
are parallel, the distance between the two lines must be 300 mm or 
more in order to prevent signal source interference.
  Communication wiring must not form a closed loop.
6.3.1 Communication wiring between the indoor and outdoor units
  The indoor and outdoor units communicate via the RS485 serial port.
  The communication wiring between the indoor and outdoor units should 
    be connected one unit after another in a daisy chain from the outdoor 
    unit to the final indoor unit.And  the  shielded  layer  must  be  properly 
grounded, and a build-out resistor must be added to the last indoor unit 
to enhance the stability of the communication system (see Figure 6.6).
  Incorrect wiring such as a star connection or a closed ring will cause 
instability of the communication system and system control anomalies.
  Use a three core shielded wire (greater than or equal to 0.75 mm
) 
for the communication wiring between the indoor and outdoor units. 
Make sure the wiring is connected correctly. The connecting lead for 
this communication wire must come from the master outdoor unit.
X1
X2
CN18
SW1 SW2 SW3 SW4
SW5
SW6
SW7
ENC1
POWER_S
CN15(
WHITE
)
To wired controller
comm. bus
Indoor Main Control Board
Wired 
controller
S6X
P6X
Display Board
CN9
To wired
controller
comm.bus 
D1  D2 
Indoor unit 1
Display board
A
B
C
D
A
B
C
D
Wired controller 1
X1 X2
Indoor unit 1
Wired controller 2
X2 X1 D2 D1
Wired controller 1
X2 X1
D2 D1
X1 X2
Indoor unit 2
X1 X2
Indoor unit n(n<=16)
D1
D2
D1
D2
D1
D2
X1 X2
Indoor unit 1
Wired controller 2
X1 X2
Wired controller 1
X1 X2
(P Q E)
(P Q E)
6.4 Handling the Electrical Wiring Connection Points
Only the last indoor unit requires adding 
the build-out resistor at P and Q.
(open)
Indoor and 
outdoor units 
Communication wire
Connecting the shielded 
layer of the shielded wire
(Connect the shielded end of the shielded wire to the 
electronic controller box sheet metal "      " here)
Signalling line 
between outdoor units
Outdoor 
unit
P
Q
Figure 6.6
  The X1/X2, D1/D2 ports on the sides of the main control board 
and the unidirectional communication port (display board side) are 
for different types of wired controllers (see Figure 6.10).
  Use the connecting wires (accessory 15) to connect the D1/D2 ports.
  Once  the  wiring  and  connections  are  done,  use  tie  straps  to 
secure the wiring properly so that the connection joint cannot be 
pulled  apart  by  external  force.  The  connection  wiring  must  be 
straight out so that the cover of the electrical box is level and can 
be closed tightly.
  Use  professional  insulation  and  sealing  materials  to  seal  and 
protect  the  perforated  wires.  Poor  sealing  may  lead  to 
condensation,  and  entry of  small  animals  and  insects  that  may 
cause short circuits in parts of the electrical system, causing the 
system to fail.
6.3.2 Communication wiring between the indoor unit and wired 
controller
Figure 6.7
Figure 6.8
2) For a unidirectional communication mode:
Use 1 wired controller to control 1 indoor unit (see Figure 6.9).
Figure 6.9
Figure 6.10
Master wired controller Slave wired controller
rellortnoc deriw evalSrellortnoc deriw retsaM
The wired controller and the indoor unit can be connected in different 
manners, depending on the forms of communication.
1) For a bidirectional communication mode:
Use 1 wired controller to control 1 indoor unit or 2 wired controllers 
 (one master and one slave controller) to control 1 indoor unit  
 (see Figure 6.7);
Use 1 wired controller to control multiple indoor units or 2 wired  
controllers (one master and one slave controller) to control 
multiple indoor units (see Figure 6.8);
Build-out 
resistor
2
A
B
C
D
For the specific connection method, refer to the instructions in the 
corresponding wired controller manual to carry out the wiring and 
connections.
Caution
• 
  All  shielded  wiring  in  the  network  are  interconnected,  and  will 
eventually connect to earth at the same point        . 
 "      "