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T-334
4--1
SECTION 4
OPERATION
4.1 INSPECTION (Before Starting)
WARNING
Beware of unannounced starting of the
evaporator and condenser fans. The unit
may cycle the fans and compressor unex-
pectedly as control requirements dictate.
a. If container is empty, check inside for the following:
1. Check channels or “T” bar floor for cleanliness.
Channels must be free of debris for proper air cir-
culation.
2. Check container panels, insulation and door seals
for damage. Effect permanent or temporary repairs.
3. Visually check evaporator fan motor mounting bolts
for proper securement (refer to paragraph 6.15).
4. Check for dirt or grease on evaporator fans or fan
deck and clean if necessary.
5. Check evaporator coil for cleanliness or obstruc-
tions. Wash with fresh water.
6. Check defrost drain pans and drain lines for obstruc-
tions and clear if necessary. Wash with fresh water.
7. Check panels on refrigeration unit for loose bolts and
condition of panels. Make sure TIR devices are in
place on access panels.
b. Check condenser coil for cleanliness. Wash with
fresh water.
c. Open control box door. Check for loose electrical con-
nections or hardware.
d. Check color of moisture-liquid indicator.
e. Check oil level in compressor sight glass.
4.2 CONNECT POWER
WARNING
Do not attempt to remove power plug(s) be-
fore turning OFF start-stop switch (ST), unit
circuit breaker(s) and external power
source.
WARNING
Make sure the power plugs are clean and
dry before connecting to power receptacle.
4.2.1 Connection To 380/460 VAC Power
1. Make sure start-stop switch (ST, on control panel)
and circuit breaker (CB-1, in the control box) are in
position “0” (OFF).
2. Plug the 460 VAC (yellow) cable into a de-energized
380/460 VAC, 3-phase power source. Energize the
power source. Place circuit breaker (CB-1) in position
“I” (ON). Close and secure control box door.
4.2.2 Connection To 190/230 VAC Power
An autotransformer (Figure 4--1) is required to allow
operation on nominal 230 volt power. It is fitted with a
230 VAC cable and a receptacle to accept the standard
460 VAC power plug. The 230 volt cable is black in color
while the 460 volt cable is yellow. The transformer may
also be equipped with a circuit breaker (CB-2). The
transformer is a step up transformer that will provide
380/460 VAC, 3-phase, 50/60 Hz power to the unit when
the 230 VAC power cable is connected to a 190/230
VAC, 3-phase power source.
1. Make sure that the start-stop switch (ST, on control
panel) and circuit breakers CB-1 (in the control box
and CB-2 (on the transformer) are in position “0”
(OFF). Plug in and lock the 460 VAC power plug at the
receptacle on the transformer.
2. Plug the 230 VAC (black) cable into a de-energized
190/230 VAC, 3-phase power source. Energize the
power source. Set circuit breakers CB-1 and CB-2 to
position “I” (ON). Close and secure control box door.
3
1
2
1. Dual Voltage Modular Autotransformer
2. Circuit Breaker (CB-2) 230-Volt
3. 460 VAC Power Receptacle
Figure 4--1 Autotransformer
4.3 ADJUST FRESH AIR MAKEUP VENT
The purpose of the fresh air makeup vent is to provide
ventilation for commodities that require fresh air
circulation. The vent
must be closed
when transporting
frozen foods.
Air exchange depends on static pressure differential,
which will vary depending on the container and how the
container is loaded.
Units may be equipped with a vent position sensor
(VPS). The VPS determines the position of the fresh air
vent and sends data to the controller display.
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