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Page 45
Wine Storage
Wine Storage
(400-
(400-
2
2
)
)
Series
Series
Electronic Control System
3-29
#3758410 - Revision C - May, 2014
FUNCTIONS OF MODEL 427R-2 REF. SECTION ELECTRONIC CONTROL SYSTEM
The following few pages explain monitoring, regulating and controlling functions of the electronic control system.
Display Zone Temperatures
Temperature signals from the compartment thermistor are monitored by the microprocessor, then displayed on the
LCD. Though the zone air temperature fluctuates, average temperature is displayed (See Figure 3-54).
NOTE:
If zone temperature changes, temperature display will change by one (1) degree per minute.
Figure 3-54. Display Zone Temperatures
UNIT
REFRIGERATOR
ON/OFF
ON/OFF
WARMER
COLDER
Average temperature displayed
Figure 3-55. Signal Trace Schematic (High Voltage) of Lighting System
115 VOLTS
60 CYCLES
HIGH VOLTAGE
L1
STARTING RELAY
COMPRESSOR
COMPRESSOR
PROTECTOR
OVERLOAD
NEUT
3
1
5
6
4
DPDT RELAY
BOARD
MAIN
BLACK
PURPLE
BLUE
WHITE
NEUTRAL WHITE
NEUTRAL WHITE
RED
PURPLE
ORANGE
BLACK
RED
YELLOW
LOWER DRAWER LIGHTS
CONDENSER FAN MOTOR
EVAPORATOR FAN MOTOR
TOP DRAWER LIGHTS
M
M
2000 Ω
MULLION HEATER
NEUTRAL WHITE
M
ORANGE
ORANGE
DOOR SWITCH
DOOR SWITCH
P4
J5
J4
J6
J3
P2
P1
P3
J2
1. 115 Volts sup-
plied to light
system unless
OFF, or in
Sabbath Mode.
2. Switch position monitored for
alarm and fan operation.
Supply Power to the Lighting System
Power is supplied to the lighting system through the control board when the unit is switched ON by pressing the
UNIT ON/OFF key. With a drawer open, the light switch allows power to the lights. (See Figure 3-55).
NOTE:
Power to the lights is monitored by the microprocessor to control the door ajar alarm feature and to help
control the operation of the evaporator fan.
NOTE:
When in Sabbath Mode, the lighting system is disabled. Sabbath Mode will be covered later.