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R-959(SL)M-AA

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R959(SL)MA

Microwave ovens contain circuitry capable of producing very high voltage and current, contact with any part of the high voltage circuit will result in
electrocution. High voltage capacitor, Power transformer, Magnetron, High voltage rectifier assembly, High voltage fuse, High voltage harness.

REMEMBER TO CHECK 3D

1) Disconnect the supply.

2) Door opened, and wedged open.

3) Discharge the high voltage capacitor.

WARNING: AGAINST THE CHARGE OF THE HIGH-VOLTAGE

CAPACITOR

The high-voltage capacitor remains charged about 60 sec-
onds after the oven has been switched off. Wait for 60 sec-
onds and then short-circuit the connection of the high-
voltage capacitor (that is, of the connecting lead of the
high-voltage rectifier) against the chassis with the use of
an insulated screwdriver. 

Sharp recommend that wherever possible fault-finding is carried out
with the supply disconnected. It may, in some cases, be necessary to
connect the supply after the outer case has been removed, in this
event carry out 3D checks and then disconnect the leads to the pri-
mary of the power transformer. Ensure that these leads remain iso-
lated from other components and the oven chassis. (Use insulation
tape if necessary.) When the testing is completed, carry out 3D checks
and reconnect the leads to the primary of the power transformer.

REMEMBER TO CHECK 4R

1) Reconnect all leads removed from components during testing.

2) Replace the outer case (cabinet).

3) Reconnect the supply.

4) Run the oven. Check all functions.

Microwave ovens should not be run empty. To test for the presence of
microwave energy within a cavity, place a cup of cold water on the
oven turntable, close the door and set the power level to HIGH
(100%). And set the microwave timer for two (2) minutes. When the
two minutes has elapsed (timer at zero) carefully check that the water
is now hot. If the water remains cold, carry out 3D checks and re-
examine the connections to the component being tested. 

When all service work is completed and the oven is fully assembled, the microwave power output should be checked and microwave leakage test
should be carried out.

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R959(SL)MA

Power Requirements

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

Power Consumption

Microwave cooking  1.55 kW   Approx   6.7A
Convection cooking 2.85 kW   Approx 11.9A 
Grill cooking             2.85 kW   Approx 11.9A 
Dual  cooking    Micro and Grill ----------------2.95kW    Approx 12.6A 
                            Micro and Convection ----- 2.95kW   Approx. 12.6A
Off Mode (Energy Save Mode) ---------------- Less than 0.5W 

Power Output

900 watts nominal of RF microwave energy (IEC60705 Test Procedure)
Operating frequency 2450 MHz

Grill heating element Power 
Output

1400W

Convection heating element 
Power Output

1400W

Outer Case Dimensions

Width  550 mm        
Height 368 mm including foot
Depth  537 mm          NOTE: The Depth does not include the door opening handle. 

Cooking Cavity Dimensions

Width  375 mm          NOTE: Internal capacity is calculated by measuring maximum width, depth and height.
Height 272 mm                     Actual capacity for holding food is less.
Depth  395 mm

Turntable diameter

362 mm

Control Complement

Touch Control System
Timer (0 - 99 minutes 90 sec.)
Microwave Power for Variable Cooking
    Repetition Rate;
   100% HIGH ...................................................... Full power throughout the cooking time
     70% MEDIUM HIGH ...................................... approx. 70% of FULL Power
     50% MEDIUM  ............................................... approx. 50% of FULL Power
     30% MEDIUM LOW  ......................................approx. 30% of FULL Power
     10%  LOW .......................................................approx. 10% of FULL Power
       0%  LOW ...................................................... 0% of FULL Power
Convection temperature control range:
     250

°C, 230°C, 220°C, 200°C, 190°C, 180°C, 160°C, 130°C, 100°C and 40°C

TIME keys
EXPRESS COOK keys
EXPRESS DEFROST keys
AUTO COOK key
LESS/MORE keys
CONVECTION key
COMBI key
AUTO MINUTE key
START key
STOP/CLEAR key
KITCHEN TIMER key
MICRO. POWER key
GRILL key
WEIGHT keys

Net Weight

Approx. 23 kg

As part of our policy of continuous improvement, we reserve the right to alter design and specifications without notice.

R-959(SL)M-AA

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R959(SL)MA

OVEN

1. Grill heating element

2. Oven lamp

3. Control panel

4. Shelf runners

5. Waveguide cover

6. Oven cavity

7. Coupling

8. Door seals and sealing surfaces

9. Door opening handle

10.Air-vent openings

11.Outer cabinet

12.Power cord

13.Turntable

14.Turntable support        15.High Rack      16.Low Rack        17.Square shelves (x2)

TOUCH CONTROL PANEL

DIGITAL DISPLAY AND INDICATORS:

1. GRILL

2.COOK

3. CONVECTION

4. MICROWAVE

KEYS:

5. TIME

6. GRILL

7. CONBI

8. EXPRESS COOK

9. EXPRESS DEFROST

10.AUTO COOK

11. LESS/MORE

12. AUTO MINUTE

13. START

14. STOP/CLEAR

15. KITCHEN TIMER

16. WEIGHT

17. CONV.(

°C)

18. MICRO. POWER

15

3

2

1

4

12

11

10

13

8

9

14

16

7

6

5

17

R-959(SL)M-AA

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R959(SL)MA

Closing the door activates the monitored latch switch and the stop
switch.

1. The control unit is not energized. The display shows nothing (Fig.

O-1 (a)).

2. Open the door. The contacts (COM-NC) of the monitored latch

switch are closed and the control unit is energized. Then contacts
of relays RY1 and RY5 are closed, and the oven lamp will light and
the display will show “  . 0” . (Fig. O-1(b)).

3. Close the door. The contacts (COM-NC) of the monitored latch

switch are opened and the contacts of relay RY1 are opened and
the oven lamp will be turned off. The display will show " . 0". (Fig.
O-1(c)).

NOTE: Energy save mode

1) If the oven has not been used for more than 3 minutes, the

contacts of the relay RY5 will be opened and the control
unit will be not energized. Open and close the door, the
control unit will resume.

Enter a desired cooking time by touching the TIME keys and start the
oven by touching START key.

                           Figure O-2 on page 14-1

1. The line voltage is supplied to the primary winding of the high volt-

age transformer. The voltage is converted to about 3.3 volts A.C.
output on the filament winding and high voltage of approximately
2000 volts A.C. on the secondary winding.

2. The filament winding voltage (3.3 volts) heats the magnetron fila-

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..

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

erates a wavelength 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.

4. When the cooking time is up, a signal tone is heard and the relays

RY1 + RY2 + RY6 go back to their home position. 

The circuits to the oven lamp, high voltage transformer, fan motor
and turntable motor are cut off.

5. When the oven door is opened during a cooking cycle, the switches

come to the following condition.

The circuit to the high voltage transformer is cut off when the contacts
of relay RY2, and the contacts (COM-NO) of the monitored latch
switch and monitor switch are made open. The circuit to the fan motor
is cut off when the relay RY6 is made open. The circuit to the turntable
motor is cut off when the contacts (COM-NO) of the monitored latch
switch are made open. The oven lamp remains on even if the oven
door is opened after the cooking cycle has been interrupted, because
the relay RY1 stays closed. Shown in the display is remaining time.

6. MONITOR SWITCH CIRCUIT

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

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

cooking program, the monitored latch switch and stop switch
must open their contacts (COM-NO) first. And the contacts
(COM-NC) of the monitored latch switch are made closed. After
that the contacts (COM-NC) of the monitor switch can be closed
and the contacts (COM-NO) of monitor switch are made open.

2) When the oven door is closed, the contacts (COMNC) of the

monitor switch must be opened and the contacts (COM-NO) of
monitor switch must be closed. After that the contacts (COM-
NO) of the monitored latch switch and the stop switch are made
closed. And the contacts (COM-NC) of the monitored latch
switch are made open.

3) 6-3. When the oven door is opened and the contacts (COM-NO)

of the monitored latch switch remain closed, the fuse F8A will
blow. Because the relay RY1 and monitor switch are closed and
a short circuit is caused.

When the microwave oven is preset for variable cooking power, the
line voltage is supplied to the high voltage transformer intermittently
within a 32-second time base through the relay contact which is cou-
pled with the current-limiting relay RY2. The following levels of micro-
wave power are given.

SETTING;

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

percentage of microwave power, because approx. 3 seconds
are needed for heating up the magnetron filament.

CONNECTED COMPONENTS

RELAY

Oven lamp, Turntable motor 

RY1

High voltage transformer 

RY2

6

Y

R

 ,

r

o

t

o

m

 

n

a

F

          CONDITION

SWITCH CONTACT 

DURING

COOKING

DOOR OPEN 

(NO COOKING)

Monitored latch 
switch 

COM-NO
COM-NC 

Closed

Opened

Opened

Closed

Stop switch   

COM-NO 

Closed 

Opened

Monitor switch        

COM-NO
COM-NC 

Closed

Opened   

Opened

Closed

100% (HIGH)

32 sec. ON

70% (MEDIUM

HIGH)

Approx. 70%

100%

24 sec. ON

8 sec. OFF

14 sec. OFF

20 sec. OFF

26 sec. OFF

%

0

5

.

x

o

r

p

p

A

)

M

U

I

D

E

M

(

%

0

5

18 sec. ON

30% (MEDIUM

LOW)

Approx. 30%

12 sec. ON

%

0

1

.

x

o

r

p

p

A

)

W

O

L

(

%

0

1

6 sec. ON