R-4G75M (serv.man7). Complete - Sharp Home Appliance Service Manual (repair manual). Page 7

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In this condition the food is cooked by both microwave
energy and grill heating elements energy simultaneously.
1. The relay RY1, RY2 and RY3 are energized.
2. The numbers of the digital readout start the count down

to zero.

3. Then following components are energized.

Power transformer

Grill heating elements

Magnetron

Turntable motor

H.V. capacitor

Fan motor

H.V. rectifier

Oven lamp

4. Now, the food is cooked by microwave and grill heating

elements energy simultaneously.

5. Upon completion of selected cooking time, audible signal

sounds and contacts of relays are opened, then the
activated components as item 3 are de-energized.

AUTO DEFROST automatically works out the correct micro-
wave power and time for defrosting. What should be done is
to chose menu and to enter the weight of food with the weight
entry touch pad. Once the oven starts, it will cook according
to the special cooking sequence.

Keep on touching the AUTO COOK pad until the desired
cooking programme appears in the display. Then using the
WEIGHT ENTRY pad, enter the weight and touch the
START pad. The cooking modes and cooking time are
automatically computed and selected based on the pro-
grammes.

Using the INSTANT COOK function, the foods are cooked or
defrosted without figuring time, power level or quantity.
When the oven senses 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 ac-
cording 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: (BOILED POTATOES)

3. Sensor detects moisture and humidity and calculates

cooking time and variable power.

Cooking Sequence.
1. Touch INSTANT COOK pad.
NOTE:

The oven should not be operated on INSTANT

COOK immediately after plugging in the unit. Wait five
minutes before cooking on INSTANT COOK.

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 food, turn it or

season, etc.

!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.

1. Potatoes at room temperature. Vapor is emitted very

slowly.

MICROWAVE

MICROWAVE

AH SENSOR

2. Heat potatoes. Moisture and humidity is emitted rapidly.

You can smell the aroma as it cooks.