Thermo King 098916, Руководство по обслуживанию

Страница: 128 / 196

Electrical Maintenance
127
Testing the Sensors
The controller constantly monitors the left hand
and right hand supply sensors, return sensor and
defrost (evaporator coil) sensor to determine when
to initiate a demand defrost. If a demand defrost is
requested and defrost has occurred within the last
90 minutes, the controller initiates a probe test to
check for a defective sensor.
During a Probe test, the LCD display shows
[PROBE TEST PLEASE WAIT]. The controller
operates the unit on high speed evaporator fans
only for 5 minutes. All sensor temperatures are
then compared:
• Sensors with large temperature differences are
discarded from the control algorithm. The
controller then activates the appropriate Alarm
codes to identify the defective sensor(s).
• If no sensors are found defective, controller
LCD display shows [RUNNING WITH HIGH
SUPPLY DIFFERENCE] message.
Sensor errors recorded during a probe test are
cleared when the next Defrost is initiated or Unit
On/Off switch is turned Off.
NOTE: A manual probe test can be performed
by a technician by selecting “SENSOR CHECK”
from the Manual Test Function menu.
A. Coil Support Brackets
B. Unit Front
C.
Insert Sensor at least 75 mm into coil
between Tube Rows 2 and 3.
Figure 71: MAGNUM 20 Evaporator Coil (Defrost)
Sensor Location
AXA0171
A. Coil Support Bracket
B. Unit Front
C.
Insert Sensor at least 75 mm into coil
between Tube Rows 2 and 3.
Figure 72: MAGNUM and MAGNUM SL Evaporator
Coil (Defrost) Sensor Location
A.
Insert Sensor into condenser coil between
Tube Rows 1 and 2
Figure 73: Condenser Coil Sensor Location
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