38
After the last indoor unit, the communication wiring should not route back to the outdoor unit as this will form a
closed loop.
In the last indoor unit, connect a resistor of 120 ohms between the P and Q terminals.
Do not bind the communication line, refrigerant piping and power cable together.
When the power cable and communication line are laid in parallel, the distance between the two lines must be 5cm
or more to prevent signal source interference.
All IDUs in a system must be powered through a power supply so that they can be powered on or off at the same
time.
All communication lines of the IDUs and ODU must be connected in a series, use the shielded wire, and the shield
layer must be grounded.
Separate power supply for the indoor units and refrigerant shut-off device.
Applicable standards: EN 55014-1 and EN 55014-2. The communication line must be shielded wire.
Figure 6-6
Figure 6-7
HyperLink (M1 M2) communication
Keep the power on/off for all IDUs.
Do not connect the HyperLink (M1 M2) communication line to the PQ or D1D2 communication line.
Arbitrary topology wiring.
Separate power supply for the indoor units and refrigerant shut-off device.
Applicable standards: EN 55014-1 and EN 55014-2. The communication line must be shielded wire.
CAUTION
CAUTION
L1+La+Ln≤2000m,
Communication wiring 2*0.75mm
2
Communication wire
Power wire
M1 M2
ODU
Refrigerant shut-off
Device
···
L1
L2
La
M1 M2 L N
Ln
Distribution box
Distribution box
Circuit breaker
N L
Circuit breaker
N L
n# IDU
M1
M2 L N
(n-1)# IDU
M1 M2 L N
1# IDU
M1 M2 L N
RS-485(P Q) communication
Power wire
Communication wire
L1+La+Ln≤1200m
,
Communication wiring 2*0.75mm
2
Resister
P
Q
ODU
Refrigerant shut-off
Device
···
L1
L2
La
P
Q L N
Ln
Distribution box
Distribution box
Circuit breaker
N L
Circuit breaker
N L
n# IDU
P
Q L N
(n-1)# IDU
P
Q L N
1# IDU
P
Q L N