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Electronic Control System
Wine Storage
Wine Storage
(400-
(400-
2
2
)
)
Series
Series
3-2
#3758410 - Revision C - May, 2014
Term/Component
Definition / Description
Control Board …………………………..The printed-circuit board (PC Board) containing the microprocessor, relays
and electrical connections for monitoring and controlling functions and opera-
tions of the unit.
Microprocessor ……………………...... An electrical component on the control board which receives electrical signals
from other components, processes that information, then sends an electrical
signal to the relays on the board to open or close, and other electronic com-
ponents in the unit to switch on or off.
Relay …………………………………… Electrical components on the control board which switch other components in
the unit ON and OFF when instructed to do so by the microprocessor.
LED (Light Emitting Diode) ………...... A small electronic “tube” that lights-up when power is supplied to it. In the
control panel assembly, LED’s are arranged to show values (numbers).
LED’s are also used as back-lighting for the indicators in the control panel.
Control Panel Assembly ……………… The information input and read-out area of the electronic control system,
located between the two wine storage compartments.
NOTE:
The model
427R-2 also has a control panel assembly at top front of the top refrigerator
drawer assembly.
Membrane Switch …………...……….. An integral part of the control panel assembly, which consists of the function
keys used for all input functions to the electronic control system.
Keys (Function Keys) ………………… The buttons on the Membrane switch used for input functions. (The keys are:
UNIT ON/OFF, LIGHTS ON/OFF, ALARM ON/OFF, COLDER, WARMER)
Indicators ………………….....………... The words and numbers that are displayed at the control panel. (Example:
Temperature displays, temperature alarm bell, “SERVICE”, and error codes.)
Set-Point ……………………………….. The desired compartment temperature, established by pressing the COLDER
or WARMER keys.
High Offset (Cut-in)………………….....During normal operation of a wine storage unit, it is the maximum evaporator
temperature the electronic control system will allow before calling for cooling.
Low Offset (Cut-out)…………………... During normal operation of a wine storage unit, it is the minimum compart-
ment air temperature the electronic control system will allow before interrupt-
ing cooling.
Offset Temperature Range …………... The difference between the low offset and the high offset.
Thermistor (Temperature Sensor) ….. A resistor with which resistance changes as temperatures around it change.
For electronic control system purposes, the microprocessor measures this
resistance and displays it as a temperature reading at the control panel.
Display Units of Measure……………...Temperatures displayed at the control panel may be in fahrenheit (°F), or cel-
sius (°C), units of measure. Switching from one to the other display units of
measure is accomplished through a series of key strokes.
Error Codes .…………………………... The code numbers accompanied by the letters “EC” that appear in the control
panel display windows during diagnostic mode if the unit experienced specific
problems related to electrical signals supplied by electrical components.
Electrical “Pulse”.................................. A non-constant supply of voltage, or electrical signal, the duration of which is
often measured in milliseconds.
Electrical Polarity..................................The positive ( + ) and negative ( - ) sides of the alternating current sinewave.
WINE STORAGE ELECTRONIC CONTROL TERMINOLOGY & COMPONENT DESCRIPTIONS
The electronic control system monitors, regulates and controls a variety of functions; it also displays temperatures,
possible problems with the appliance and the temperature alarm bell status.
The table below defines some basic electronic control terminology. An understanding of this information is needed
in order to comprehend the operations and functions of the electronic control system.
