©2005 McQuay International
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8 Wiring connection
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1 Electrical wiring connection:
Digital scroll product electrical circuit have strong power circuit and weak power circuit;
Power of indoor and outdoor units must be supplied simultaneously;
Cable of power and cable of communication shall be designed in parallel, and maintain more than 20cm between the two cables;
Cable of communication shall be screened, to avoid the interference of strong signal;total length of signal wires should be less than 1000m;
Signal wires has 2 poles of A and B, the same pole must be in one connection (A can not be connected with B);
Screened layer of signal wires should be connected with master unit until it is earthed;
Each circuit shall has its own independent fuse or air switch;
Outdoor units use 3 phase power supply cable, indoor units use 1 phase power supply cable;
Wiring diagram is shown in units;
8
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2 Wiring of communication specification:
As shown as below
：
A
：
conducting wiring
（
copper, intersection surface is more than 0.5mm
2
or 20AWG
）
B
：
Insulation material
C
：
Screen layer(efficiency shall be higher than 95%)
D
：
outside layer protector(PVC)
Note:
For wiring cable, refer to UL2547 and UL2791 standard;
8. 3 Electrical connection
8.3.1 For single outdoor units
W irin g c a b le
Fuse
Switch
Electrical connection for single outdoor unit <1>(FOR MDS080
～
240BR)
Two-core cable
(power circuit)
Two-core cable
(power circuit)
Switch
Fuse
Fuse
Switch
L1
Switch
Fuse
L2
L1
L3 N
Power
N
L2 L3
Indoor unit
Outdoor unit
