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11
WIRING THE COMMUNICATION TERMINAL
BLOCK — Figure 17 is the communication port diagram for
the outdoor unit.
Fig. 17 —Outdoor Unit Communication Port
Diagram
COMMUNICATION CABLE — The type of
communication cable used is a 2-core stranded shielded cable.
The diameter of the wire should be AWG 18. The maximum
wire length should be less than or equal to 3,937 feet between
outdoor and indoor units and less than or equal to 820 feet
between the wired controller and indoor units. Communication
wires are sold separately but can be obtained through Carrier.
Figure 18 below shows a typical communication wire from
Carrier.
Fig. 18 —Typical Communication Wire
CONTROL CONNECTIONS — Control power comes from
the control board in the outdoor unit and does NOT require a
separate source.
Use of 2-core stranded shielded cable is required. Shield is
used to protect the signal from interference. The control wire
between outdoor and indoor units is bus type. See Fig. 19 for
communication wiring.
COMMUNICATION WIRING — Communication
wire
must be wired as shown in Fig. 8 and 19. Do not route
communication wire with high voltage power wire or allow it
to come in contact with non-insulated piping and sharp edges.
LEGEND
K1, K2
Reserved
O, A
To pulse meter
X, Y
To indoor unit centralized controller
P, Q
To indoor units communication bus
H1, H2
Reserved
IMPORTANT: Wiring for communication shall be 2
inches. or more apart from power source wiring to avoid
electric noise. Do not insert control/communication and
power source wire in the same conduit.
Pay attention to the polarity of communication wire.