Royal Vendors RVV 700, Руководство по эксплуатации и обслуживанию

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RVV 700 Standard Programming Service and Parts Manual
SECTION 2: Vender Component Explanation
Refrigeration System
The vender’s refrigeration system is responsible for the
cooling of the cabinet and the products loaded within it.
The refrigeration system comes as a completely sealed unit
and should never be cut or tapped into, or the warranty
will be voided.
OPERATION REQUIREMENTS
The refrigeration system requires 115 volts AC from
the main wiring harness for it to operate. The main
wiring harness will get its voltage for the unit from the
refrigeration relay.
COOLING SOFTWARE FEATURES
The RVV 700 controller software includes the following
refrigeration modes and features:
• Normal and Pull Down Modes: During Pull Down
mode, the evaporator fan is always in high speed
during ON and OFF compressor cycles. In normal
mode the evaporator fan is: high speed when
compressor is ON, until cut-out temperature is
reached; low speed when the compressor if OFF,
until cut-in temperature is reached; high speed and
compressor OFF for four-minutes delay after cut-in
temperature is reached; then return to high speed
with compressor ON. After a power failure or when
the door is closed, the system starts in Pull Down
Mode and a 60-minute timer starts. If Normal Mode
compressor cut-out temperature is reached within this
60 minutes, the system reverts to Normal Mode; if
not it will stay in Pull Down Mode. When the system
running in Pull Down Mode reaches the Pull Down
Mode compressor cut-out temperature, the system
will continue to operate in Pull Down Mode for 50
compressor cycles, then revert to Normal Mode. Only
the machine set point is adjustable by the customer.
Normal and Pull Down cut-ins and cut-outs are offsets
from the set point and factory set.
• Defrost Mode: In Pull Down Mode, there is a one-
time 15-minute defrost l4 hours after start of Pull
Down Mode. In Normal Mode, there is a four-minute
delay for the compressor to start when Normal Mode
cut-in temperature is reached. During this four-minute
delay, the fan runs at high speed.
If the unit is already in the defrost mode when the
door is opened, the defrost function will continue after
the door is closed. Because of that, the compressor
may not restart for as much as 30 minutes after the
door is closed.
• Door Switch Inactivation Mode: If the door switch
does not activate, the fluorescent lights will stay off
and the refrigeration unit will not run until 30 minutes
have passed. After 30 minutes, the controller will
assume that the switch may be defective and will then
start the cooling process. In this mode, the evaporator
fan will cycle with the refrigeration unit (similar to
Normal Mode, but without the counter).
• Compressor Motor Save Mode: If the controller
calls for cooling continuously for 24 hours, the
vender will go into a defrost mode for one hour. If
the refrigeration unit still does not cycle after an
additional eight hours, a no pull-down error will be
displayed. Note: This no pull-down error is not
self-clearing; it must be cleared manually through the
service menu or through DEX.
REFRIGERATION COMPONENTS
The refrigeration system is a sealed system. Described in
this section are explanations of the refrigeration system’s
major components.
Capillary Tube - The capillary tube is located in the
refrigerant line, between the condenser and evaporator
coils. The small diameter tube is used as a metering
device to control the flow of liquid refrigerant to the
evaporator coil. This creates low pressure causing the
refrigerant to vaporize and absorb heat as it passes through
the evaporator coil.
Compressor - The compressor is a hermetically-sealed
unit located beneath (outside) the cooling compartment.
The compressor is a pump, driven by the compressor
motor which draws low-pressure vapor (refrigerant) from
the evaporator coil, compresses it, and forces it into the
condenser under high pressure. The motor is started and
controlled by the refrigeration relay.
Condenser - The condenser is located beneath (outside) the
cooling compartment next to the compressor. It can be seen
from the front with the door open. The condenser removes
heat from the high-pressure vapor discharged from the
compressor and condenses it to a high-pressure liquid. The
condenser and evaporator coils have aluminum fins attached
to effectively increase heat exchange surfaces.
Starting Relay - The starting relay is mounted on the side
of the compressor housing. The compressor motor has
two windings (start winding and run winding). To give the
motor torque when it first starts, the starting relay switches