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In interests of user-safety the oven should be restored to its original
condition and only parts identical to those specified should be used.

Page

SERVICING ................................................................................................................................................ 1
CAUTION, MICROWAVE RADIATION, WARNING .................................................................................... 1
PRODUCT SPECIFICATIONS ...................................................................................................................  2
OPERATION SEQUENCE ..........................................................................................................................  3
FUNCTION OF IMPORTANT COMPONENTS ..........................................................................................  3
TEST PROCEDURE .................................................................................................................................... 4
TOUCH CONTROL ASSEMBLY ................................................................................................................. 7
WIRING / RE-WIRING WARNING ............................................................................................................. 10
COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE .....................................................  10
MICROWAVE MEASUREMENT.................................................................................................................13
WIRING DIAGRAMS ................................................................................................................................. 14
PARTS LIST .............................................................................................................................................  19
OVEN PARTS ............................................................................................................................................ 21
CONTROL PANEL PARTS/DOOR PARTS ............................................................................................... 22
MISCELLANEOUS/PACKING & ACCESSORIES ..................................................................................... 23

R

E

Quartz Dual Grill

ROAST PORK

AST PORK

ROAST POUL

AST POULTR

TRY

CHICKEN POR

CHICKEN PORTIONS

TIONS

ROAST

AST BEEF / LAMB 

 BEEF / LAMB 

R-753

LESS

LESS

MORE

MORE

DOWN

DOWN

UP

UP

Kg  Lb  Pcs

Kg  Lb  Pcs

Time

Time

POWER LEVEL

POWER LEVEL

STOP

CLEAR

CLEAR

START

START

AUTO MINUTE

AUTO MINUTE

TIMER

TIMER

KITCHEN

KITCHEN

Kg/Lb

Kg/Lb

AUTO START

AUTO START

GRILL

GRILL

DU

DUAL GRILL

AL GRILL

MICROWAVE

MICROWAVE

CLOCK

CLOCK

SOUP

SOUP

KG•LB

TURN

STIR

GRILL MICRO COOK

1

753M -

Microwave ovens contain circuitry capable of producing very high voltage and current.  Contact with the following parts
will result in electrocution.
High voltage capacitor, High voltage transformer, Magnetron, High voltage rectifier assembly, High voltage harness.

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 to HIGH 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.

1) Disconnect the supply.
2) Door opened, and wedged open.
3) Discharge high voltage capacitor.

The high-voltage capacitor remains charged about
60 seconds after the oven has been switched off.
Wait for 60 seconds and then short-circuit the
connection of the high-voltage capacitor (that is,
of the connecting lead of the high-voltage recti-
fier) against the chassis with the use of an insu-
lated 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 primary
of the power transformer. Ensure that these leads
remain isolated 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.

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

Servicing and repair work must be carried out only by
trained service engineers.

All the parts marked "*" on parts list are used at
voltages more than 250V.

Removal of the outer wrap gives access to potentials
above 250V.

All the parts marked "

∆

" on parts list may cause undue

microwave exposure, by themselves, or when they
are damaged, loosened or removed.

Service engineers should not be exposed to the
microwave energy which may radiate from the
magnetron or other microwave generating de-
vices if it is improperly used or connected. All
input and output microwave connections,
waveguides, flanges and gaskets must be se-
cured. Never operate the device without a micro-
wave energy absorbing load attached. Never
look into an open waveguide or antenna while the
device is energized.

Whilst the maximum leakage permitted in BS EN 60335-2-25 is 50Wm

2

 (equivalent to 5mW/cm

2

, it is not normal to detect

any significant leakage, and therefore any detected leakage should be investigated.

THE WIRES IN THIS MAINS LEAD ARE COLOURED IN

ACCORDANCE WITH THE FOLLOWING CODE:
GREEN-AND-YELLOW : EARTH        BLUE : NEUTRAL        BROWN : LIVE

2

753M -

Power Requirements

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

Power Consumption

Microwave cooking   1.55 kW Approx.     7 A
Grill cooking              1.25 kW Approx.   5 A
Dual cooking             2.75 kW Approx. 12 A

Power Output

900W watts nominal of RF microwave energy
(measured by way of IEC 705) Operating frequency of 2450 MHz

Grill Heating Element Power Output

1200W (600W x 2)

Case Dimensions

Width 520mm     Height 305mm including foot     Depth 413mm

Cooking Cavity Dimensions

Width 342mm     Height 207mm                           Depth 368mm

Turntable diameter

325mm

Control Complement

Touch Control System     Clock(1:00-12:59 or 0:00-23:59)
Timer (0-99 minutes 90 seconds)
Microwave Power for Variable Cooking Repetition Rate;

HIGH Full power throughout the cooking time
MEDIUM HIGH approx. 70% of Full Power
MEDIUM approx. 50% of Full Power
MEDIUM LOW approx. 30% of Full Power
LOW ...  approx. 10% of Full Power

FUNCTION KEYS:

AUTO COOK keys

INSTANT COOK keys

AUTO DEFROST key LESS (    )/MORE (    ) keys,

Time keys

MICROWAVE POWER LEVEL key,

GRILL key

DUAL GRILL key, STOP/CLEAR key,

TIMER key

AUTO MINUTE/START key

AUTO START CLOCK key

WEIGHT keys

Set Weight

Approx. 18 kg

3

753M -

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

When the door is opened during a cook cycle, the switches
come to the following condition.

CONDITION

DURING

DOOR OPEN

SWITCH

CONTACT

COOKING

(NO COOKING)

Monitored latch switch

COM-NO

Closed

Open

Monitor switch

COM-NC

Open

Closed

COM-NO

Closed

Open

Stop switch

COM-NO

Closed

Open

When the oven door is opened and the contacts of the
monitored latch switch SW1 remain closed, the fuse F8A
will blow.

LATCH
HEAD

DOOR

LATCH
HOOK

MONITOR
SWITCH
SW2

MONITORED
SWITCH
SW1

STOP
SWITCH
SW3

DOOR OPEN BUTTON

OPEN LEVER

1.  When the oven door is closed, the contacts (COM-

NO) must be closed.

2.  When the oven door is opened, the contacts (COM-

NO) must be opened.

f the oven door is opened and the contacts

(COM-NO) of the monitored latch switch SW1 fail
to open, the fuse F8A blows simultaneously with
closing the contacts (COM-NC) of the monitor
switch SW2.

CAUTION:  BEFORE REPLACING A BLOWN

FUSE F8A TEST THE MONITORED
LATCH SWITCH SW1, MONITOR
SWITCH SW2.

The following levels of microwave power are given.

SETTING

1.  The contact of monitored latch switch SW1 are

closed.

2.  The relay RY1, RY2 and RY3 are energised.
3.  When cooking in dual mode the microwave power is

limited to 70% (via the I.C.).

32 sec. ON

24 sec. ON

18 sec. ON

12 sec. ON

6 sec. ON

8 sec. OFF

14 sec. OFF

20 sec. OFF

26 sec. OFF

HIGH

MEDIUM HIGH

MEDIUM

MEDIUM LOW

LOW

Approx. 70%

Approx 100%

Approx. 50%

Approx. 30%

Approx. 10%