Carrier 30GTN Service And Troubleshooting Manual page 4

It is important when connecting to a CCN communication
bus that a color coding scheme be used for the entire net-
work 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 containing 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 com-
munication bus cable exits from one building and enters an-
other, the shields must be connected to grounds at the light-
ning 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 TB3 of the plug,
the white wire to COM terminal, and the black wire to
the (−) terminal.
4. The RJ14 CCN connector on TB3 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 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.
PIN
STATUS SWITCH CONNECTION
POINT
Oil Pressure, Ckt B J7-1, 2 (MBB)
Oil Pressure, Ckt A J7-3, 4 (MBB)
Remote On/Off TB5-13, 14
Compressor Fault
J5-8, 12 (CXB)
Signal, B3
Compressor Fault
J9-2, 12 (MBB)
Signal, B2
Compressor Fault
J9-8, 12 (MBB)
Signal, B1
Compressor Fault
J5-5, 12 (CXB)
Signal, A4
Compressor Fault
J5-11, 12 (CXB)
Signal, A3
Compressor Fault
J9-5, 12 (MBB)
Signal, A2
Compressor Fault
J9-11, 12 (MBB) CR/CPCS-A1†
Signal, A1
LEGEND
CPCS — Compressor Protection Control System
CR — Control Relay
CXB — Compressor Expansion Board
MBB — Main Base Board
OPS — Oil Pressure Switch, Circuit A or B
*The OPS can also be added as an accessory.
†The CPCS can be added as an accessory.
Table 3 — Status Switches
070
040-060 (50 Hz)
(50 Hz)
040-070 (60 Hz) 245B-315B
080, 230B
Not Used* OPSB
Not Used* OPSA
Not Used Not Used
Not Used Not Used
CR/CPCS-B1† CPCS-B1
Not Used Not Used
Not Used Not Used
Not Used CPCS-A2
CPCS-A1
Table 2 — Thermistor Designations
PIN
THERMISTOR
CONNECTION
NO.
POINT
T1 J8-13,14 (MBB) Cooler Leaving Fluid
T2 J8-11,12 (MBB) Cooler Entering Fluid
T3 J8-21,22 (MBB)
J8-15,16 (MBB) Saturated Condensing
T4
J8-24,25 (MBB) Cooler Suction Temperature,
T5
J8-18,19 (MBB) Cooler Suction Temperature,
T6
J5-11,12 (EXV) Compressor Suction Gas
T7
J5-9,10 (EXV) Compressor Suction Gas
T8
T9 J8-7,8 (MBB)
T10 J8-5,6 (MBB)
LEGEND
EXV — Electronic Expansion Valve
MBB — Main Base Board
090-110, 130 130 (50 Hz)
(60 Hz) 150, 230A-255A
OPSB OPSB OPSB
OPSA OPSA OPSA
Field-Installed Relay Closure
Not Used Not Used Not Used
CPCS-B2 CR-B2 CR-B2
CPCS-B1 CR-B1 CR-B1
Not Used Not Used Not Used
Not Used Not Used CR-A3
CPCS-A2 CR-A2 CR-A2
CPCS-A1 CR-A1 CR-A1
4
THERMISTOR INPUT
Saturated Condensing
Temperature, Ckt A
Temperature, Ckt B
Ckt A (EXV Only)
Ckt B (EXV Only)
Temperature, Ckt A (EXV Only)
Temperature, Ckt B (EXV Only)
Outdoor-Air Temperature Sensor
(Accessory)
Remote Space Temperature
Sensor (Accessory)
170,190,
210, 315A,
270A,290A,330A/B,
390A, 420A/B
360A/B, 390B
OPSB OPSB
OPSA OPSA
CR-B3 CR-B3
CR-B2 CR-B2
CR-B1 CR-B1
Not Used CR-A4
CR-A3 CR-A3
CR-A2 CR-A2
CR-A1 CR-A1