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Fig. 12 — Typical Communication Wiring of Heat Recovery System
LEGEND
AWG
—
American Wire Gage
IDU
—
Indoor Unit
MDC
—
Multiport Distribution Controller
P Q
X Y
Main MDC
X Y
MDC
outdoor unit
Centralized controller
HA HB
P Q
P Q
P Q
P Q
P Q
P Q
Wired controller
HA HB
indoor
To No.1
To No.2
indoor
To No.3
indoor
To No.4
indoor
indoor
To No.1
To No.2
indoor
To outdoor
To Sub.MDC
To outdoor
Indoor unit 1#
L1
L2
L3
L3
L3
L3
L4
L5
L6
L7
L8
L9
L10
1
1
L
Indoor unit 2#
Indoor unit 3#
Indoor unit 4#
Indoor unit 5#
Indoor unit 6#
HA
HB
HA
HB
HA
HB
HA
HB
HA
HB
HA
HB
Touch screen
wired controller
Note: 24v DC Power
Note: Power from IDU
Maximum wiring length
L1+L2 </= 3937 ft. 16 AWG, 2-Core Stranded Shield
L3 </= 3937 ft. 16 AWG, 2-Core Stranded Shield
L4
L4 </= 3937 ft. 16 AWG, 2-Core Stranded Shield
L5 </= 3937 ft. 16 AWG, 2-Core Stranded Shield
L6+L7+L8+L9 </= 820 ft. 16-20 AWG, 2-Core Stranded Shield
L10+L11 </= 820 ft. 16-20 AWG, 2-Core Stranded Shield
11