Carrier TRANSICOLD INTEGRA 30S, Руководство по эксплуатации и обслуживанию

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4-1 62-10848
SECTION 4
Temperature Control
4.1 Sequence of Operation
General operation sequences for cooling, null, and
heating are provided in the following paragraphs. The
microprocessor automatically selects the mode neces-
sary to maintain refrigerated compartment temperature
at set point.
4.1.1 Perishable Mode
The unit operates in the perishable mode with set
points above 10°F (-12°C)
a. With return air temperature above set point and
decreasing, the unit will be cooling with the com-
pressor and evaporator fans operating. (See
Section 2.8.1 for a description of the refrigera-
tion circuit during cooling) The condenser fan
will operate for the first three minutes after start
up then operate under the control of the con-
denser pressure control switch (HP2). The
green unit operating LED will operate in accor-
dance with
Figure 3.2 or Figure 3.3 .
b. If discharge temperature increases to the set
point of the quench thermostat (BPT), the ther-
mostat will close, energizing the quench valve
(BPV). This will allow liquid into the suction line
in order to cool compressor. Once the discharge
temperature decreases to the certainty of the
PPT, the thermostat will open, DE-energizing
the PP.
c. Once temperature decreases to the certainty,
the unit will enter the null mode. If the continu-
ous air flow parameter is set to ON, the evapo-
rator fans will continue to operate with all other
components OFF. If the continuous air flow
parameter is OFF, the evaporator fans and all
other components will be OFF. A 5 minute delay
is required before restart is allowed.
d. If temperature increases during the null mode,
the unit will restart in cooling.
e. If temperature continues to decrease, the unit
will enter the heating mode with the compressor
and evaporator fans operating and the hot gas
solenoid valve (HGS1) energized (open). The
condenser fan and condenser pressure control
valve (HGS2) will operate under the control of
the condenser pressure switch (HP2). If the
engine coolant or electric heat option is
installed, the optional heaters will also be ener-
gized. (See
Figure 2.8.2 for a description of the
refrigeration circuit during heat and defrost.)
Figure 4.1 Operating Sequence - Perishable Mode
4.1.2 Frozen Mode
The unit operates in the frozen mode with set points at
or below 10°F (-12°C). Operation in the frozen mode is
the same as in the perishable mode except no heating
takes place.
Figure 4.2 Operating Sequence - Frozen Mode
+ 1.8
_
F (+ 1
_
C)
or + 3.6
_
F (+ 2
_
C )
or + 5.4
_
F (+ 3
_
C )
SETPOINT
-- 1.8
_
F (-- 1
_
C)
or -- 3.6
_
F (-- 2
_
C)
or -- 5.4
_
F (-- 3
_
C)
(setting)
COOL
UNIT STOPPED
HEAT
+ 1.8
_
F (+ 1
_
C )
or + 3.6
_
F (+ 2
_
C )
or + 5.4
_
F (+ 3
_
C )
SETPOINT
-- 1.8
_
F (-- 1
_
C)
or -- 3.6
_
F (-- 2
_
C)
or -- 5.4
_
F (-- 3
_
C)
(setting)
COOL
UNIT STOPPED