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Electronic Control Information
WARMING DRAWER WWD30
GENERAL INFORMATION:
Electronic control will provide temperature control in the warming drawer as determined and set by user. Up and
down arrow keys are provided to increase and decrease, respectively, the temperature of the drawer and operation
time. Temperature control range of the warming drawer main board control will be 80ºF to 200ºF (26.7ºC to 93.3ºC).
Amplitude of this temperature control will be ± 5ºF. When the control sees a temperature at the thermistor 5ºF above
setpoint, control will open the element relay. Once the control sees a thermistor temperature of 5ºF below setpoint,
the relay will close allowing element to cycle on.
Power/Relay Board
Circulation Fan
Element
Display Board/
Keypad
Flex Cable
(Inner ceiling)
(Network Cable)
Electronic Control Board
(Behind Front Panel)
Door Switch
(Bottom of Drawer Front)
Display
Beeper
CONTROL (all low
temp components)
Keypad
Communications
Thermistor
POWER BOARD
AC Fan
Element
(850W)
Flex Cable
Door Input
DLB
(CB/CE Model only)
Figure 3-1. Component Location Top View.
Figure 3-2. Electronic Control System Diagram.
TIMER
PROOF
LOW
PRESETS
HIGH
MED
TEMP
POWER
ON/OFF
PROOF
F
TEMP
TEMP
TEMP
ON
TIMER
LCD Display
Power On/Off
Temperature
Controls
Preset Controls
Timer Controls
Figure 3-3. Keyboard Layout.