7
R-330BK
R-330BW
Figure O-1. Oven Schematic-Off Condition
SCHEMATIC
NOTE: CONDITION OF OVEN
1.
DOOR CLOSED
2.
CLOCK APPEARS ON DISPLAY
enough steam from the food, it relays the information to its
microprocessor which will calculate the remaining cooking
time and power level needed for best results. When the food
is cooked, water vapor is developed. The sensor “senses”
the vapor and its resistance increases gradually. When the
resistance reaches the value set according to the menu,
supplementary cooking is started.
The time of supplementary cooking is determined by experi-
ment with each food category and inputted into the LSI.
An example of how sensor works: (POTATOES)
1. Potates at room temperature. Vapor is emitted very
slowly.
MICROWAVE
2. Heat Potates. Moisture and humidity is emitted rapidly.
You can smell the aroma as it cooks.
MICROWAVE
AH SENSOR
3. Sensor detects moisture and humidity and calculates
cooking time and variable power.
Cooking Sequence.
1. Touch one of the SENSOR pads and then touch the
START pad.
NOTE: The oven should not be operated on SENSOR
immediately after plugging in the unit. Wait two
minutes before cooking on SENSOR.
2. The coil of shut-off relay (RY-1) is energized, the turntable
motor, oven lamp and cooling fan motor are turned on,
but the power transformer is not turned on.
3. After about 16 seconds, the cook relay (RY-2) is
energized. The power transformer is turned on,
microwave energy is produced and first stage is started.
The 16 seconds is the cooling time required to remove
any vapor from the oven cavity and sensor.
NOTE: During this first stage, do not open the door or touch
STOP/CLEAR pad.
4. When the sensor detects the vapor emitted from the
food, the display switches over to the remaining cooking
time and the timer counts down to zero.
At this time, the door may be opened to stir, turn, or
season food.
5. When the timer reaches zero, an audible signal sounds.
The shut-off relay and cook relay are de-energized and
the power transformer, oven lamp, etc. are turned off.
6. Opening the door or touching the STOP/CLEAR pad, the
time of day will reappear on the display and the oven will
revert to an OFF condition.
120V AC
60 Hz
OVEN
LAMP
TURN-
TABLE
MOTOR
FAN
MOTOR
POWER
TRANSFORMER
CAPACITOR 1.0
µ
F
AC 2300V
MONITOR
SWITCH
RECTIFIER
MAGNETRON
SECONDARY
INTERLOCK
SWITCH
TTM
OL
FM
MONITOR
FUSE 20A
A1
A2
COM.
COM.
N.O.
N.O.
DOOR
SENSING
SWITCH
(RY-1)
(RY-2)
CONTROL UNIT
PRIMARY
INTERLOCK
RELAY
THERMAL
CUT-OUT (OVEN)
THERMAL
CUT-OUT (MG.)
SH-B
SH-A
GRN
F3
F1
F2
AH SENSOR