Comfortlink Control Boards; Ccn Wiring Diagram - Carrier 38APS025 Manual

NOTE: Conductors and drain wire must be 20 AWG (Ameri-
can Wire Gage) minimum stranded, tinned copper. Individual
conductors 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 –4 F
to 140 F (–20 C to 60 C) is required. Wire manufactured by
Alpha (2413 or 5463), American (A22503), Belden (8772), or
Columbia (02525) meets these requirements.
It is important when connecting to a CCN communication
bus that a color coding scheme be used for the entire network
to simplify the installation. It is recommended that red be used
for the signal positive, black for the signal negative, and white
for the signal ground. Use a similar scheme for cables contain-
ing different colored wires.
At each system element, the shields of its communication
bus cables must be tied together. If the communication bus is
entirely within one building, the resulting continuous shield
must be connected to a ground at one point only. If the commu-
nication bus cable exits from one building and enters another,
the shields must be connected to grounds at the lightning
suppressor in each building where the cable enters or exits the
building (one point per building only). To connect the unit to
the network:
1. Turn off power to the control box.
2. Cut the CCN wire and strip the ends of the red (+), white
(ground), and black (–) conductors. (Substitute appropri-
ate colors for different colored cables.)
3. Connect the red wire to (+) terminal on LVT of the plug,
the white wire to COM terminal, and the black wire to the
(–) terminal.
4. The RJ14 CCN connector on LVT can also be used, but is
only intended for temporary connection (for example, a
laptop computer running Service Tool).
IMPORTANT: A shorted CCN bus cable will prevent some
routines from running and may prevent the unit from start-
ing. If abnormal conditions occur, unplug the connector. If
conditions return to normal, check the CCN connector and
cable. Run new cable if necessary. A short in one section of
the bus can cause problems with all system elements on the
bus.
*Registered trademark of Dupont.
Fig. 18 — CCN Wiring Diagram

ComfortLink Control Boards

CONTROL BOARD COMMUNICATION
ComfortLink control boards are communicating controls on
the Local Equipment Network (LEN). Several light-emitting
diodes (LEDs) indicate status of the board communciations.
Red LED — Proper operation of the control boards can be
visually checked by looking at the red status LEDs. During ini-
tial power-up the LED will signal a
followed by a pause. This indicates that the processor is boot-
ing. If this pattern repeats, it is an indication that the control
board is in a continuous reboot loop and the board should be re-
placed. When operating correctly, the red status LEDs should
be blinking in unison at a rate of once every 2 seconds. If the
red LEDs are not blinking in unison, verify that correct power
is being supplied to all modules. Be sure that the main control
is supplied with the current software. If necessary, reload cur-
rent software. If the problem still persists, replace the control
board. A red LED that is lit continuously or blinking at a rate of
once per second or faster indicates that the control board
should be replaced.
Green LED — The MBB has one green LED. The Local
Equipment Network (LEN) LED should always be blinking
whenever power is on. All other boards, except the scrolling
marquee and Navigator, have a LEN LED which should be
blinking whenever power is on and the device is communciat-
ing. If a particular board is installed but not required, it will not
be communicating. An AUX1 board without the digital com-
pressor or Motormaster options enabled is an example. Check
LEN connections for potential communication errors at the
board J3 and/or J4 connectors. Communication between mod-
ules is accomplished by a 3-wire sensor bus. These 3 wires run
in parallel from module to module. The J4 connector on the
MBB provides both power and communication directly to the
marquee display only.
Yellow LED — The Main Base Board has one yellow LED.
The Carrier Comfort Network
times of network communication.
MAIN BASE BOARD (MBB) — See Fig. 19. The MBB is
the heart of the ComfortLink control system. It contains the
major portion of operating software and controls the operation
of the machine. The MBB continuously monitors input/output
channel information received from its inputs and from all other
modules. The MBB receives inputs from the discharge and
suction pressure transducers, current sensor boards (CSB) and
thermistors. The MBB also receives the discrete inputs from
23
/ -second blink 3 times,
1
2
(CCN) LED will blink during
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