Thermo King KD-II SR, Руководство пользователя

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Unit Description (Rev. 04/03)
9
2. FUSE LINK WIRE. The fuse link is located between
the unit harness and the battery. At a current draw of
approximately 50 to 55 amperes, the fusible link will
melt and cut all power to the unit controls.
3. HIGH PRESSURE CUTOUT. The high pressure
cutout is a pressure sensitive switch that is located in
the compressor discharge manifold. If the discharge
pressure rises above 470 psig (3241 kPa) for R-404A
systems or 325 psig (2088 kPa) for R-134a systems.
On SR models, the HPCO switch opens the HPCO
input to the microprocessor interface board. The con-
troller stops the unit and then records an alarm.
4. HIGH PRESSURE RELIEF VALVE. The high pres-
sure relief valve is designed to relieve excess pressure
within the refrigeration system. The valve is a spring-
loaded piston that lifts off its seat when refrigerant
pressure exceeds 500 psig (3447 kPa). The valve will
reseat when the pressure drops to 400 psig (2758 kPa).
The valve could possibly leak refrigerant after it has
relieved excess pressure. Tapping the valve lightly may
help the valve reseat and SEAL PROPERLY. The valve
is non-repairable and requires no adjustment. If the
valve fails to reseat properly, remove the refrigerant
charge and unscrew and replace the valve.
The high pressure relief valve is located on a high pres-
sure line near the condenser. Its location is such that
when the pressure is expelled from the valve, it would
be directed away from anyone servicing the unit.
5. LOW OIL LEVEL SWITCH. The low oil level
switch closes if the oil drops below a certain level. If it
stays closed for a specified time, the microprocessor
will shut the unit down and record alarm code 66.
6. PREHEAT BUZZER. The preheat buzzer sounds
when the CYCLE-SENTRY system energizes the glow
plugs.
7. OIL PRESSURE SENSOR. The oil pressure switch
closes when oil pressure is too low.
On SR models an oil pressure sensor provides an OPS
input to the microprocessor interface board. If the oil
pressure remains too low, the controller stops the unit
and records an alarm.
8. WATER TEMPERATURE SWITCH. The water
temperature switch closes when the engine coolant
temperature is too high.
On SR models, the water temperature switch provides a
WTS input to the microprocessor interface board. If the
engine coolant temperature is too high, the controller
stops the unit and records an alarm.
9. OVERLOAD RELAY (Models 25 and 50). An over-
load relay protects the standby electric motor. The over-
load relay opens to stop the electric motor if the motor
overloads (e.g., low line voltage or improper power
supply) while the unit is on electric standby operation.
On SR models an auxiliary contact signals the µP-T
controller that the overload relay has tripped. The con-
troller then generates an alarm. When the alarm is
cleared, the controller sends a 1 second pulse to the
reset solenoid to reset the overload relay.
10. EVAPORATOR COIL SENSOR. Evaporator high
temperature protection is provided by the µP-T control-
ler using an evaporator coil sensor. If the evaporator
temperature becomes excessive, the controller records
an alarm and may stop the unit.
11. PREHEAT INDICATOR BUZZER. The preheat
indicator buzzer is energized whenever the GLOW
PLUGS are energized on units equipped with CYCLE-
SENTRY.
WARNING: On CYCLE-SENTRY Auto Start-
Stop operation, the glow plugs do not always
preheat before the engine starts.