Thermo King CRR-40 119, Руководство пользователя

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Operating Instructions
47
• Compressor Discharge Temperature
Control (Chill Mode Only):
A. Liquid injection is activated at compressor
discharge temperatures between 115 C and
125 C (239 F and 257 F). The controller
pulses the liquid injection valve open and
closed on a 1 minute duty cycle. For example,
the valve may be energized for 15 seconds and
de-energized for 45 seconds. Number of
seconds the valve is energized is based on the
discharge temperature and the KVQ valve
setting.
B. Liquid injection is activated when the KVQ
Setting less than 5 C (8.9 F) below the return
air temperature. The controller energizes
liquid injection valve for 6 seconds every 60
seconds regardless of the discharge
temperature.
5. HIGH PRESSURE CUTOUT (HPCO)
SWITCH. If the compressor discharge
pressure rises above 2240 +/- 70 kPa, 22.4 +/-
0.7 bar, 325 +/- 10 psig, the high pressure
cutout opens to interrupt the ground circuit to
the compressor contactor:
• Compressor STOPS immediately.
• Evaporator and condenser fans continue
normal operation. Controller determines that a
high pressure cutout switch is open when the
unit current draw decreases by 7 amps for
more than 3 seconds.
• The controller LCD display shows a High
Pressure Cutout message in the Misc.
Functions Status Menu: “High Pressure
Cutout Check Condenser Probe” or “High
Pressure Cutout Check Condenser Fan”.
• After 1 minute, the controller energizes the
compressor contactor so the compressor will
restart when the over-load condition is
corrected (switch resets) if power is available.
The high pressure switch resets (closes) when
the pressure drops to 1590 +/- 70 kPa, 15.9 +/-
0.7 bar, 230 +/- 10 psig.
• If the switch remains open for 5 minutes,
controller also activates Alarm LED and
records Alarm 37, Total Power Consumption
Too Low.
6. FUSIBLE PLUG FOR HIGH PRESSURE
RELIEF. A fusible plug is installed in the
water-cooled condenser-receiver tank to avoid
excessive pressure build-up within the
refrigeration system from extraordinary and
unforeseen circumstances. The plug blows
when the plug temperature reaches 100 C (212
F). The plug is located so that refrigerant
pressure expelled from the valve would be
directed away from anyone servicing the unit.
The plug is non-repairable and requires no
adjustment. If the plug blows, recover the
remaining refrigerant charge and replace the
fusible plug.
7. OVERLOAD PROTECTION. The condenser
fan motor, evaporator fan motors and
compressor motors include internal overload
protection with automatic reset.
8. PHASE SEQUENCE SELECTION. When
the On/Off switch is turned ON, phase sensors
on the main relay board determine the
incoming power phase to ensure proper
condenser and evaporator fan rotation.
Pretrip Inspection
Visual Inspection
The following inspections should be made before
the container is loaded:
1. Visually check the unit for physical damage.
2. Check the electrical connections in the unit
control box, making sure they are fastened
securely.
3. Check the conditions of wires and terminals.
Repair or replace if necessary.
4. Check the refrigeration system for leaks.
Inspect for evidence of oil leaks at all joints
and connections.
5. Check the condenser and evaporator coils.
Clean if necessary. Use an air or water spray
jet directed against the coil from the air
discharge side. Also inspect the condenser fan
grille for damage. If the grille is damaged or
missing, abnormally high head pressure may
result. Repair or replace the grille if necessary.