Connect Accessories; Connect The Ccn Communication Bus; Communication Bus Wire Specifications; Connection To The Communication Bus - Carrier 42C Installation And Start-Up Instructions Manual

Connect Accessories —
tion instructions for installation procedures. Fan coil controller
wiring is shown for the following accessories:
• Linkage Thermostat (Fig. 16)
• Condensate Pump Switch (Fig. 17)
• Two-Position Minimum Outdoor Air Damper (Fig. 18)
• Remote Occupancy (Fig. 19)
Connect the CCN Communication Bus —
coil controllers connect to the bus in a daisy chain arrangement.
The fan coil controller may be installed on a primary CCN bus
or on a secondary bus from the primary CCN bus. Connecting to
a secondary bus is recommended.
At any baud (9600, 19200, 38400 baud), the number of con-
trollers is limited to 239 zones maximum. When Carrier link-
age thermostats are used on the same bus as fan coil units, no
more than 128 fan coils and 12 linkage thermostats may be on
the same bus. Bus length may not exceed 4000 ft, with no more
than 60 total devices on any 1000-ft section. Optically isolated
RS-485 repeaters are required every 1000 ft.
NOTE: Carrier linkage thermostats operate at 9600 band.
The first fan coil controller in a network connects directly to
the bridge and the others are wired sequentially in a daisy chain
fashion. Refer to Fig. 20 for an illustration of CCN Communi-
cation Bus wiring.
The CCN Communication Bus may also connect to the fan
coil controller space temperature sensor. Refer to the Install
Sensors section for sensor wiring instructions.
COMMUNICATION BUS WIRE SPECIFICATIONS —
The Carrier Comfort Network (CCN) Communication Bus
wiring is field-supplied and field-installed. It consists of
shielded three-conductor cable with drain (ground) wire. The
cable selected must be identical to the CCN Communication
Bus wire used for the entire network. See Table 3 for recom-
mended cable.
Table 3 — Recommended Cables
MANUFACTURER
Alpha
American
Belden
Columbia
NOTE: Conductors and drain wire must be at least 20 AWG
(American Wire Gage), stranded, and tinned copper. Individual con-
ductors must be insulated with PVC, PVC/nylon, vinyl, Teflon, or
polyethylene. An aluminum/polyester 100% foil shield and an outer
jacket of PVC, PVC/nylon, chrome vinyl, or Teflon with a minimum
operating temperature range of –20 C to 60 C is required.
Refer to accessory installa-
The fan
CABLE PART NO.
2413 or 5463
A22503
8772
02525

CONNECTION TO THE COMMUNICATION BUS

1. Strip the ends of the red, green/white, and black conduc-
tors of the communication bus cable.
2. Connect one end of the communication bus cable to the
bridge communication port labeled COMM2 (if connect-
ing on a secondary bus).
When connecting the communication bus cable, a color
code system for the entire network is recommended to
simplify installation and checkout. See Table 4 for the
recommended color code.
Table 4 — Color Code Recommendations
SIGNAL TYPE
+
Ground
–
3. Connect the other end of the communication bus cable to
the terminal block labeled CCN in the fan coil controller
of the first air terminal. Following the color code in
Table 4, connect the Red (+) wire to Terminal 1. Connect
the Green/White (ground) wire to Terminal 2. Connect
the Black (–) wire to Terminal 3.
4. Connect additional fan coil controllers in a daisy chain
fashion, following the color coded wiring scheme in
Table 4. Refer to Fig. 20.
NOTE: The communication bus drain wires (shield) must be
tied together at each fan coil controller. If the communication
bus is entirely within one building, the resulting continuous
shield must be connected to ground at only one single point. If
the communication bus cable exits from one building and
enters another building, connect the shields to ground at a
lightning suppressor in each building where the cable enters or
exits (one point only).
13
CCN BUS WIRE PLUG PIN
COLOR NUMBER
Red 1
Green/White 2
Black 3