![background image](http://html1.mh-extra.com/html/carrier/transicold-x4-7300/transicold-x4-7300_operation-and-service-manual_2564193035.webp)
62-11637
2–10
2.4.3
Compressor Suction Modulation Valve
(CSMV)
The CSMV opens and closes as required for capacity
control of the refrigeration system cooling cycle. It is
located in the suction line within the evaporator assem-
bly.
2.4.4
Evaporator Switches, Transducers and
Sensors
a. Evaporator Outlet Pressure Transducer (EVOP)
The EVOP is located in the suction line near the evapo-
rator expansion valve. It provides the control system
with evaporator outlet pressure information to be dis-
played, recorded in the DataLink data recorder and
used to determine the required position of the evapora-
tor expansion valve.
b. Evaporator Outlet Temperature Sensor (EVOT)
The EVOT is a thermistor type sensor located on the
suction line near the evaporator expansion valve. It
provides the control system with evaporator outlet tem-
perature information to be displayed, recorded in the
DataLink data recorder and used to determine the
required position of the evaporator expansion valve.
c. Defrost Termination Temperature Sensor (DTT)
The DTT is a thermistor type sensor located on the
center tube sheet of the evaporator coil. It provides the
control system with evaporator temperature informa-
tion to be displayed, recorded in the DataLink data
recorder and used to determine termination of defrost.
d. Return Air Temperature Sensor (RAT)
The RAT is a thermistor type temperature control probe
which provides the control system with information on
the temperature of the air entering the evaporator sec-
tion. The reading is displayed, recorded in the DataLink
data recorder and used to control the refrigeration sys-
tem. It is located on a bracket behind the center of the
return air grille.
e. Supply Air Temperature Sensor (SAT)
The SAT is a thermistor type temperature control probe
which provides the control system with information on
the temperature of the air leaving the evaporator sec-
tion. The reading is displayed, recorded in the DataLink
data recorder and used to control the refrigeration sys-
tem. It is located in the supply air outlet housing.
2.5
SYSTEM OPERATING CONTROLS AND COM-
PONENTS
Temperature control is provided by the Carrier Transi-
cold APX
TM
control system. Once the system is set at
the desired temperature, the unit will operate automati-
cally to maintain the desired temperature within very
close limits.
2.5.1
Multiple Languages
Messages in the MessageCenter can be displayed in
English or Spanish. Refer to
for more
information on language selection.
2.5.2
Automatic Start-Stop
Standard equipment includes an auto start-stop fea-
ture. This feature provides automatic cycling of the die-
sel engine, which in turn offers an energy efficient
alternative to continuous operation of the engine with
control of temperature accomplished by alternate cool-
ing and heating of the supply air (evaporator outlet air).
2.5.3
Special Features
The following additional special features are incorpo-
rated into the Carrier Transicold APX control system:
• An easy to read LCD display MessageCenter
which clearly displays all required information.
• Unit Data and Advanced User selectable Func-
tional Parameters.
• Programmable Maintenance Hour Meters
• Bright LED Alarm Light.
• Fully Automated Pretrip.
• Automated control system Self-test.
• DataLink data recorder (uses System date and
time).
• Trip Start to record date/time of trip in DataLink
data recorder memory.
• USB communication for downloading data,
upgrading operational software, and Configura-
tion set up.
• Automatic Engine Starting.
• Functional Parameter locks.
• Alarms are stored in control system memory for
future reference.
2.5.4
Component Description And Location
The APX control systems is an automotive style,
decentralized, modular system with CAN bus (Con-
trolled Area Network) connectivity. Hardware associ-
ated with the system includes the power control
module (PCM - item 27,
), main micropro-
cessor module (MM - item 28), stepper valve module
(SVM - item 10). engine control unit (ENCU
−
Item 15)
and display module (DM - item 11).
NOTICE
Under no circumstances should anyone
attempt to repair sealed module internal
components. Should a problem develop
with these components, contact your
nearest Carrier Transicold dealer for
replacement.
Summary of Contents for Transicold X4 7300
Page 21: ...62 11637 1 6 1 3 SAFETY DECALS ...
Page 22: ...1 7 62 11637 62 03958 ...
Page 23: ...62 11637 1 8 ...
Page 24: ...1 9 62 11637 ...
Page 119: ...62 11637 SECTION 6 MESSAGECENTER PARAGRAPH NUMBER Page 6 1 MESSAGECENTER MESSAGES 6 1 ...
Page 278: ......