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CRR-20 & CRR-40, September 1999
General Description
Model CRR-20SL and CRR-40 units are all-electric, single-
piece, refrigeration units with bottom air supply. Each unit is
designed to cool and heat containers for shipboard or overland
transit. Each unit mounts in the front wall of the container.
CRR-20SL units feature a slimline frame. Fork lift pockets are
provided for installation and removal of the unit.
The frame and bulkhead panels are constructed of alu-
minum and are treated to resist corrosion. A hinged, remov-
able evaporator compartment door provides easy service
access. All operating components except the evaporator coil
can be replaced from the front of the unit.
Each unit is equipped with an 18.3 m (60 ft) power cable
for operation on 460-380V/3 Ph/60-50 Hz power. For opera-
tion on 460-380V/3 Ph/60-50 Hz power, plug the 460-380V
power cable into the proper power supply.
Each unit is equipped with 460-380V/3 Ph/60-50 Hz elec-
tric motors. An automatic phase correction system provides
the proper electrical phase sequence for compressor, condenser
fan and evaporator fan motor operation. The unit power cable
is stored below the control box in the condenser section.
Unit features include a semi-hermetic reciprocating com-
pressor with a liquid injection system; 2-speed evaporator fans;
a fresh air exchange system; and a Thermoguard
®
µ
P-D micro-
processor controller with indicator LEDs. The
µ
P-D controller
controls, monitors and records unit operation using supply air,
return air, evaporator coil, condenser coil, ambient and compres-
sor discharge temperature sensors. For additional unit feature
information, see “CRR Model Features” on pages vi through viii
of the Introduction.
Semi-hermetic Reciprocating Compressor with
Liquid Injection Cooling System
The refrigeration unit includes a semi-hermetic reciprocating
compressor with forced feed lubrication system, ambient com-
pensated internal overload and high temperature protectors,
and a refrigerant injection system.
Dual Speed Evaporator Fans
CRR models are equipped with either 2 or 3 evaporator fans.
All models feature 2-speed motors. The evaporator fans operate
continuously to circulate air inside the container. The fans oper-
ate on high speed for perishable cargo at return air temperatures
of -9.9 C (14.1 F) and above. At return air temperatures of -10 C
(14 F) and below, the evaporator fans operate on low speed for
frozen cargo.
NOTE: If Economy Mode is ON:
• Fresh Loads: Evaporator fans operate on low
speed when container temperature is in-range.
• Frozen Loads: Evaporator fans stop during the
Null mode; controller operates fans on low speed
for 5 minutes every 45 minutes.
Fresh Air Exchange System
The fresh air exchange system removes harmful gases from
containers carrying sensitive perishable commodities. The
fresh air vent is located above the control box. The fresh air
vent is adjustable to accommodate a variety of cargo and
chilled load operating conditions. The fresh air vent should be
tightly closed when carrying frozen cargo.
Thermoguard
®
µµ
P-D Controller
The
µ
P-D controller incorporates refrigeration system compo-
nent control, thermostat, digital thermometer, fault indicator
and data recording capabilities into one self-contained pack-
age. The
µ
P-D controller provides accurate air temperature
control of perishable and frozen cargo.
The controller features a weather tight, corrosion resis-
tance enclosure. Two large alpha-numeric digital displays are
backlit and tilted for easy viewing. Ten control keys provide
quick access to unit operating information and easy comple-
tion of setpoint, manual defrost, pretrip and start-of-trip pro-
gramming.
A
µ
P-D output module is used by the controller to ener-
gize and de-energize various contactors and solenoids. An
2
Unit Description
Содержание CRR-20
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