Major System Components; General; Unit Sizes And Modular Combinations; Main Base Board (Mbb) - Carrier Air Conditioner Operation And Service Manual

Table 1A — Unit Sizes and Modular Combinations
(30GTN,R)
UNIT NOMINAL
30GTN,R TONS UNIT 30GTN,R
40
040
045 45
050 50
060 60
070 70
080 80
090 90
100 100
110 110
130 125
150 145
170 160
190 180
210 200
230 220
245 230
255 240
270 260
290 280
315 300
330 325
360 350
390 380
420 400
*60 Hz units/50 Hz units.
Table 1B — Unit Sizes and Modular Combinations
(30GUN,R)
UNIT NOMINAL
30GUN,R TONS UNIT 30GUN,R
040 26
045 28
050 34
060 42
070 48
080 55
090 59
100 66
110 72
130 84
150 99
170 110
190 122
210 134
230 154
245 158
255 165
270 176
290 193
315 206
330 219
360 243
390 256
420 268
*60 Hz units/50 Hz units.

MAJOR SYSTEM COMPONENTS

General —
The 30GTN,R and 30GUN,R air-cooled recip-
rocating chillers contain the ComfortLink™ electronic control
system that controls and monitors all operations of the chiller.
The control system is composed of several components as
listed in the sections below. See Fig. 1 for typical control box
drawing. See Fig. 2-4 for control schematics.
Main Base Board (MBB) —
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 thermistors T1-T6,
T9, and T10. See Table 2. The MBB also receives the feedback
SECTION A SECTION B
UNIT 30GTN,R
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
150 080
150 090
150 100
170 100
190 110
210 110
170 170
190 190/170*
210 190
210 210
SECTION A SECTION B
UNIT 30GUN,R
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
150 080
150 090
150 100
170 100
190 110
210 110
170 170
190 190/170*
210 190
210 210
See Fig. 5. The MBB is
inputs from compressors A1, A2, B1 and B2, and other status
switches. See Table 3. The MBB also controls several outputs.
Relay outputs controlled by the MBB are shown in Table 4.
Information is transmitted between modules via a 3-wire com-
munication bus or LEN (Local Equipment Network). The
CCN (Carrier Comfort Network) bus is also supported. Con-
nections to both LEN and CCN buses are made at TB3. See
Fig. 5.
Expansion Valve (EXV) Board —
pansion valve (EXV) board receives inputs from thermistors
T7 and T8. See Table 2. The EXV board communicates with
the MBB and directly controls the expansion valves to main-
tain the correct compressor superheat.
Compressor Expansion Board (CXB) —
CXB is included as standard on sizes 150-210 (60 Hz) and 130
(50 Hz) and associated modular units. The compressor expan-
sion board (CXB) receives the feedback inputs from compres-
sors A3, B3 and A4. See Table 3. The CXB board communi-
cates the status to the MBB and controls the outputs for these
compressors. An additional CXB is required for unit sizes 040-
110, 130 (60 Hz), 230B-315B with additional unloaders.
Scrolling Marquee Display —
pad interface used for accessing chiller information, reading
sensor values, and testing the chiller. The marquee display is a
4-key, 4-character, 16-segment LED (light-emitting diode) dis-
play. Eleven mode LEDs are located on the display as well as
an Alarm Status LED. See Marquee Display Usage section on
page 29 for further details.
Energy Management Module (EMM) —
EMM module is available as a factory-installed option or as a
field-installed accessory. The EMM module receives 4 to
20 mA inputs for the temperature reset, cooling set point reset
and demand limit functions. The EMM module also receives
the switch inputs for the field-installed 2-stage demand limit
and ice done functions. The EMM module communicates the
status of all inputs with the MBB, and the MBB adjusts the
control point, capacity limit, and other functions according to
the inputs received.

Enable/Off/Remote Contact Switch

Enable/Off/Remote Contact switch is a 3-position switch used
to control the chiller. When switched to the Enable position the
chiller is under its own control. Move the switch to the Off po-
sition to shut the chiller down. Move the switch to the Remote
Contact position and a field installed dry contact can be used to
start the chiller. The contacts must be rated for dry circuit appli-
cation capable of handling a 24 vac load. In the Enable and Re-
mote Contact (dry contacts closed) positions, the chiller is al-
lowed to operate and respond to the scheduling configuration,
CCN configuration and set point data. See Fig. 6.
Emergency On/Off Switch —
Off switch should only be used when it is required to shut the
chiller off immediately. Power to the MBB, EMM, CXB, and
marquee display is interrupted when this switch is off and all
outputs from these modules will be turned off. The EXV board
is powered separately, but expansion valves will be closed as a
result of the loss of communication with the MBB. There is no
pumpout cycle when this switch is used. See Fig. 6.
Reset Button —
A reset button is located on the fuse/
circuit breaker panel for unit sizes 130-210 and associated
modules. The reset button must be pressed to reset either
Circuit Ground Fault board in the event of a trip.
Board Addresses —
a 3-position Instance jumper that must be set to '1.' All other
boards have 4-position DIP switches. All switches are set to
'On' for all boards.
3
The electronic ex-
This device is the key-
—
The Emergency On/
The Main Base Board (MBB) has
The
The
The