7.3.1 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 connect 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 7.6).
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
2
) 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.
Figure 7.9
Indoor unit 1
Display Board
A
B
C
D
A
B
C
D
Wired Controller 1
7.4 Handling the Electrical Wiring Connection Points
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 7.10).
Use the connecting wires (accessory 8) 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.
1
Main Board
SW5 SW4 SW3 SW2 SW1
ENC1
SW6 SW7
Figure 7.8
Master wired controller
Slave wired controller
X1 X2
Indoor unit 1
Wired Controller 2
X1
X2
D1
D2
Wired Controller 1
X2
X1
D1
D2
Indoor unit 2
X1 X2
Indoor unit n(n<=16)
D1
D2
D1
D2
D1
D2
Only the last indoor unit requires adding the
build-out resistor at P and Q.
(open)
Indoor and
outdoor units
Communication
wire
(P Q E)
Connecting the shielded
layer of the shielded wire
(P Q E)
(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
Build-out
resistor
36
Figure 7.6
7.3.2 Communication wiring between the indoor unit and wired controller
Figure 7.7
X1 X2
Indoor unit 1
Wired Controller 2
X1
X2
Wired Controller 1
X1
X2
2) For a unidirectional communication mode:
Use 1 wired controller to control 1 indoor unit (see Figure 7.9).
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 7.7);
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 7.8);
For the specific connection method, refer to the instructions in the
corresponding wired controller manual to carry out the wiring and
connections.
Caution
$
Figure 7.10
CN15
XS4 XP4
CN17
Display
CN9
To outdoor/indoor
units comm. bus
To wired
controller
P Q E
X1 X2
Yellow
Gray
Black
White
Blue
XT2
To wired
controller
comm. bus
D1 D2
Wired
controller
A
B
C
D
KJR-29B1/BK-E (CL92869)
KJR-86C-E (CL92870)
WDC-120GWK (CL97810)
WDC-86E/KD (CL97811)
KJR-29B1/BK-E (CL92869)
KJR-86C-E (CL92870)
WDC-120GWK (CL97810)
WDC-120GWK (CL97810)
Master wired controller
WDC-120GWK (CL97810)
WDC-86E/KD (CL97811)
Slave wired controller
WDC-120GWK (CL97810)
WDC-86E/KD (CL97811)
