123
ACCESSORY NAVIGATOR™ DISPLAY — The accesso-
ry handheld Navigator display can be used with the 48/50Z
series units. See Fig. 32. The Navigator display operates the
same way as the scrolling marquee device. The RCB and ECB
boards contain a second LEN port than can be used with the
handheld Navigator display.
CONTROL MODULE COMMUNICATIONS
Red LED — Proper operation of the control boards can be
visually checked by looking at the red status LEDs as shown
on Fig. 26-29. When operating correctly, the red status LEDs
should blink 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. Also, be sure that the main
base board is supplied with the current software and that all
boards are configured on. If necessary, reload current software.
If the problem still persists, a board may need to be replaced. A
board LED that is lit continuously or blinking at a rate of once
per second or faster indicates that the board should be replaced.
Green LED — The boards also have a green LED, which is
the indicator of the operation of the LEN communications,
which is used for communications between the boards. On the
MBB board the Local Equipment Network (LEN) LED should
always be blinking whenever power is on. All other boards
have a LEN LED that will blink whenever power is on and
there is communication occurring. If LEN LED is not blinking,
check LEN connections for potential communication errors (J3
and J4 connectors). A 3-wire sensor bus accomplishes commu-
nication between modules. These 3 wires run in parallel from
module to module.
Yellow LED — The MBB has one yellow LED. The Carrier
Comfort Network® (CCN) LED will blink during times of
network communication. The other boards do not have a CCN
communications port.
CARRIER COMFORT NETWORK INTERFACE — The
48/50Z Series units can be connected to the CCN if desired.
See Fig. 33. The communication bus wiring is a shielded,
3-conductor cable with drain wire and is field supplied and in-
stalled. See the Installation Instructions for wiring information.
The system elements are connected to the communication
bus in a daisy chain arrangement. The positive pin of each
system element communication connector must be wired to the
positive pins of the system elements on either side of it. This is
also required for the negative and signal ground pins of each
system element. Wiring connections for CCN should be made
at the COMM board. See Fig. 16. Consult the CCN Contrac-
tor’s Manual for further information.
NOTE: Conductors and drain wire must be 20-AWG
(American 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 tempera-
ture range of –20 C to 60 C is required.
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 the COMM
board, the white wire to COM terminal on the COMM
board, and the black wire to the (–) terminal on the
COMM board.
4. The RJ14 CCN connector on the COMM board can also
be used, but is only intended for temporary connection
(for example, a laptop computer running Service Tool).
5. Restore power to unit.
IMPORTANT: A shorted CCN bus cable will prevent
some routines from running and may prevent the unit
from starting. 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.
Run Status
Service Test
Temperatures
Pressures
Setpoints
Inputs
Outputs
Configuration
Time Clock
Operating Modes
Alarms
ENTER
ESC
MODE
Alarm Status
TIME
EWT
LWT
SETP
12.58
54.6F
44.1 F
44.0F
NAVIGATOR
ComfortLink
Fig. 32 — Accessory Navigator Display