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Depth  368 mm

R-291(K)M

3 – 1

R218L(W)

Power Requirements

230 - 240 Volts 
50 Hertz
Single phase, 3 wire earthed

Power Consumption

  1.22 kW 

Power Output

800 watts nominal of RF microwave energy (measured by method of IEC 60705)
Operating frequency 2450 MHz

Outside Dimensions

Width  460 mm
Height 275 mm including foot

Cooking Cavity Dimensions

Width  319 mm     

Height 211 mm                

Depth  336 mm

Turntable diameter

  272 mm

Control Complement

Timer (0 - 30 minutes)
Microwave Power for Variable Cooking
    Repetition Rate;
   HIGH ................................................................ 800 W
   MEDIUM HIGH ............................................. 700 W
   MEDIUM  ........................................................ 500 W
   LOW ................................................................. 200 W

Set Weight (Approx.)

   12 kg

R-291(K)M

4 – 1

1. Ventilation 

openings

2.   Oven lamp
3.   Door hinges
4.   Door safety latches
5.   See through door
6.   Door seals sealing surfaces
7.   Coupling
8.   Control panel
9.   Waveguide cover
10.  Power supply cord
11.  Turntable
12.  Roller stay
13.  Outer case cabinet
14.  Door opening handle

11

12

1

10

13

2

7

3

8

14

4

4

5

6

9

Defrost Pad
Press to select the
Defrost menu.

Power Level Pad
Press to select microwave
power setting.

Time Pads
Press to enter cooking
time.

START / Sensor Reheat Pad
• Press to start oven after

setting programmes.

• Press to start Sensor

Reheat operation.

Beverages Pad
Press to select
Beverages menu

Stop Pad
• Press to clear during

programming.

• Press to stop operation

of oven during cooking.

Less/More Time Pads
Press to alter the
cooking result for automatic
operations.

R-291(K)M

5 – 1

R218L(W)

1. When the timer knob is at “0”, the oven is OFF condition.

2. Closing the oven door activates the monitored latch switch and the

latch switch.

IMPORTANT

When the oven door is closed, the contacts (COM-NC) of the monitor
switch must be open.

When the microwave oven is plugged in a wall outlet, rated voltage is
supplied to the fuse holder assembly.

                                            Figure O-1 on page 12-1 

Set the cooking control to HIGH and then set the timer.

Function sequence 

                           

1. Following components are energized.

High voltage capacitor   High voltage fuse

Turntable motor         Timer motor         Fan motor

2. Rated voltage is supplied to the primary winding of the high voltage

transformer. The voltage is converted to about 3.3 volts A.C. output

volts A.C. on the secondary winding.

ment and the high voltage (2000 volts) is sent to the voltage dou-
bling circuit, where it is doubled to negative voltage of
approximately 4000 volts D.C..

4. The 2450 MHz microwave energy produced in the magnetron gen-

erates a wave length of 12.24 cm. This energy is channelled
through the waveguide (transport channel) into the oven cavity,
where the food is placed to be cooked.

5. When the cooking time is up, the timer returns to “0”, the bell rings

and the contacts of the timer switch are opened. The following

High voltage capacitor     High voltage fuse

Turntable motor         Timer motor          Fan motor

Magnetron               Oven lamp

6. When the oven door is opened during a cook cycle, the switches

come to the following position and they are common to the other
cooking conditions too.

The circuits to the high voltage transformer, turntable motor, timer

contacts (COM-NO) of the monitored latch switch and latch switch
are made open.

The timer stops to indicate how much cooking time remains. 

7. MONITOR SWITCH CIRCUIT

The monitor switch is mechanically controlled by oven door, and
monitors the operation of the monitored latch switch and the relay
RY1.

1) When the oven door is opened during or after the cycle of a

cooking program, the monitored latch switch and latch switch

(COM-NC) of the monitor switch can be closed.

2) When the oven door is closed, the contacts (COM-NC) of the

(COM-NO) of the monitored latch switch and the latch switch
are closed.

3) When the oven door is opened and the contacts (COM-NO) of

the monitored latch switch and contacts of the timer switch and
the contact of the relay RY1 remain closed, the fuse T6.3A will
blow, because the monitor switch  is closed and a short circuit is
caused.

When the microwave oven is preset  for variable cooking power, rated
voltage is supplied to the high voltage  transformer intermittently within
a 32-second time base through the relay contact which is coupled with
the current-limiting relay. The following levels of microwave power are
given.

SETTING;

NOTE: The ON/OFF time ratio does not exactly correspond to the

percentage of microwave power, because approx. 3 seconds

CONNECTED COMPONENTS

RELAY

High voltage transforme                                     RY1

          CONDITION

SWITCH CONTACT 

DURING 

COOKING

DOOR OPEN 

(NO COOKING)

Monitored latch 
switch 

COM-NO          Closed 

Open

Latch switch               COM-NO          Closed 

Open

Monitor switch             COM-NC           Open               Closed

HIGH

32 sec. ON

MEDIUM HIGH

700 W

800 W

29 sec. ON

3 sec. OFF

4 sec. OFF

500 W

M

U

I

D

E

M

21 sec. ON

200 W

W

O

L

6 sec. ON

10 sec. OFF

6 sec. ON

10 sec. OFF

5 – 2

1. 1.Operate the oven in sensor cooking mode by referring to the

operation manual.

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 inverter unit
is not turned on.

3. After about 16 seconds, the cook relay (RY-2) is energized. The

inverter unit 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 dis-

play 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 inverter unit,
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. The fan motor will operate for one minute after cooking.

R-291(K)M

Using the SENSOR function, the food is cooked 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 according to the menu, supplemen-
tary cooking is started. The time of supplementary cooking is deter-
mined by experiment with each food category and inputted into the
LSI.

An example of how sensor works: (JACKET POTATOES)

1. Potatoes at room temperature. Vapor is emitted very slowly.

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

smell the aroma as it cooks.;

3. Sensor detects moisture and humidity and calculates cooking time

and variable power.

MICROWAVE

MICROWAVE

HUMIDITY SENSOR