Traulsen TBC13, Руководство по обслуживанию

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VII. SEQUENCE OF OPERATION
VII. a - REFRIGERATION SYSTEM - HOLD MODE:
1. The controller monitors the air temperature and
senses a need for cooling.
a) The relay that controls the compressor is
energized.
3. The expansion valve monitors the evaporator
superheat and meters the amount of refrigerant
entering the evaporator.
4. The controller senses the air temperature
requirements have been met.
a) De-energizes the relay that controls the
compressor.
5. Unit is cycled by controller.
VII. b - REMOTE REFRIGERATION SYSTEM (TBC1H,
TBC1HR, TBC2H & TBC2HR only):
1. The controller must be in a chill or hold mode.
2. The controller monitors the air temperature and
senses a need for cooling.
a) The relay that controls the solenoid valve is
energized.
1-Solenoid valve is energized and refrigerant
flows to the evaporator.
2-Fans are operating at high speed.
3. The low pressure switch closes with pressure
rise.
a) The compressor motor is energized and
refrigerant is pumped through the system.
4. The expansion valve monitors the evaporator
superheat and meters the amount of refrigerant
entering the evaporator.
5. The controller senses the air temperature
requirements have been met.
a) De-energizes the relay that controls the
solenoid valve.
1-Solenoid valve is de-energized and closes.
Refrigerant flow to the evaporator stops.
2-Fan operation changes to low speed.
6. Compressor continues to run. Low pressure
control opens as pressure drops.
a) Compressor motor de-energized.
7. Unit is cycled by controller.
VII. c - IDLE MODE:
1. Conditions
a) Unit connected to correct voltage.
b) Safety thermostat closed.
2. Door heater energized.
3. Main switch closed - controller energized.
a) Main contactor energized, contacts close.
4. Controller displays main menu.
5. Controller maintains cabinet air temperature at
hold mode temperature.
VII. d - HOLD MODE:
Product will be held automatically at chilled tempera-
ture when all active probes have reached the target
temperature when in
any
mode. If a
“
BY TIME
”
mode
is selected, the unit enters hold mode automatically
after the time has expired.
VII. d - HOLD MODE (cont ’ d):
1. Unit is in IDLE mode.
2. Hold mode is initiated.
NOTE: When the hold mode is initiated, two timers
run. One tracks the time in the hold mode and the
other tracks the time since the last defrost (hold
mode defrosts at a programable interval).
a) The refrigeration system will cycle on the air
temperature of the cabinet.
1-ON at the set-point plus differential.
2-OFF when set-point reached.
b) The hold mode has an automatic defrost
cycle. The operator can program the
interval between defrost cycles to suit their
operational needs.
1-When the defrost cycle is complete and the
unit returns to the hold mode, the
evaporator fans will not operate until the
coil temperature is below 20°F.
3. Hold mode is terminated by pressing the exit key.
NOTE: If the HOLD MODE is terminated by the op-
erator with the defrost cycle in progress, the defrost
mode will continue until completion before going
into idle mode.
VII. e - BY TIME CHILL MODE:
1. Unit is in IDLE mode.
2. Chill type is selected and a cycle time is entered
then start key is pressed.
3. The refrigeration system will cycle on the
blasting air temperature set-point.
a) ON at the set-point plus differential.
b) OFF when set-point is reached.
4. If SPEED has been selected, the refrigeration
system will cycle on the new blasting air
temperature set-point after softchill condition is
met, i.e. 70 percent of time has expired.
5. Chill mode is terminated when time expires.
a) Buzzer sounds until muted.
6. At the end of a chill cycle the unit will enter the
hold mode.
a) If the end of the chill cycle is acknowledged
by pressing the STOP/RESET key, the unit
will enter the idle mode.
VII. f - CHILL OR FREEZE MODE BY TEMP:
1. Unit is in IDLE mode.
2. Chill type is selected and a target temperature is
entered then start key pressed and probe
selected.
3. The refrigeration system will cycle on the
blasting air temperature set-point.
4. Chill mode is terminated when all the product
probes reach the target chill temperature.