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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 ................................................................................................................. INSIDE FRONT COVER
CAUTION, MICROWAVE RADIATION .............................................................................................................  1
WARNING .......................................................................................................................................................... 1
PRODUCT SPECIFICATIONS .........................................................................................................................  2
GENERAL INFORMATION ................................................................................................................................ 2
APPEARANCE VIEW .......................................................................................................................................  3
OPERATION SEQUENCE ................................................................................................................................  4
FUNCTION OF IMPORTANT COMPONENTS ................................................................................................  5
TROUBLESHOOTING GUIDE .......................................................................................................................... 6
TEST PROCEDURE .........................................................................................................................................  7
TOUCH CONTROL PANEL ASSEMBLY ........................................................................................................ 13
COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE ...........................................................  20
MICROWAVE MEASUREMENT ....................................................................................................................  25
WIRING DIAGRAM .........................................................................................................................................  26
PICTORIAL DIAGRAM ...................................................................................................................................  27
CONTROL PANEL CIRCUIT ........................................................................................................................... 28
PRINTED WIRING BOARD ............................................................................................................................. 29
PARTS LIST ...................................................................................................................................................  30

1000W/ R-21AT

DEF

ON

NO. X2 CHECK

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

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

WARNING: AGAINST THE CHARGE OF THE 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 rectifier) against the chassis using a screwdriver with an insulated handle.

Sharp recommend that wherever possible fault-finding is carried out with the supply disconnected. In some
cases, it may be necessary to connect the supply with the cover removed to carry out fault investigation in the
circuitry. In such cases, the high voltage circuit should be disabled as described below to reduce the hazards:-

Carry out 3D checks (see above)
Disconnect the supply leads from the high voltage transformer, making a note of the polarity. Insulate the
connectors, ensuring they are positioned away from the transformer and fastened there.
Connect any relevant test equipment e.g. voltmeter.
Reconnect the oven to the supply, then close the door.
Note the results of the test, taking care to keep clear of the operational oven.
Carry out 3D checks (see above).
Reconnect the leads to the transformer. Take care to observe correct polarity.
Carry out 4R checks (see below).

Microwave ovens should not be used without load. To test for the presence of microwave energy within a
cavity, place a cup of cold water on the ceramic shelf, close the door and set the microwave timer for one (1)
minute, set the power level to HIGH (100%) and push the start key. When the one (1) minute has elapsed
(timer at zero) carefully check that the water is now hot.

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.

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.

IMPORTANT: If the oven becomes inoperative because of a blown fuse M10A Fuse, check the monitored 1st.

interlock switch and monitor switch before replacing the fuse M10A.

Before carrying out any work; carry out 3D checks.
1) Disconnect the power supply.
2) Open the door and wedge open.
3) Discharge the high voltage capacitor.

1) Wires must not touch:

a) High voltage parts:
b) Parts that become hot.
c) Sharp edges
d) Movable parts

2) Positive lock connectors are fitted correctly.
3) Wires are connected correctly as per pictorial dia-

gram.

4) Now wire leads are trapped by the outer wrap.

1

This Manual has been prepared to provide Sharp Corp. Service
engineers with Operation and Service Information.

It is recommended that service engineers carefully study the entire text
of this manual, so they will be qualified to render satisfactory customer
service.

CAUTION

MICROWAVE RADIATION

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

WARNING

Never operate the oven until the following points are ensured.
(A) The door is tightly closed.
(B) The door brackets and hinges are not defective.
(C) The door packing is not damaged.
(D) The door is not deformed or warped.
(E) There is not any other visible damage with the oven.

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.

PRODUCT SPECIFICATIONS

GENERAL INFORMATION

APPEARANCE VIEW

OPERATING SEQUENCE

FUNCTION OF IMPORTANT
COMPONENTS

SERVICING AND
TROUBLESHOOTING GUIDE

TEST PROCEDURE

TOUCH CONTROL PANEL

COMPONENT REPLACEMENT
AND ADJUSTMENT PROCEDURE

MICROWAVE MEASUREMENT

WIRING DIAGRAM

PARTS LIST

2

THE WIRES IN THIS MAINS LEAD ARE COLOURED IN ACCORDANCE WITH THE FOLLOWING CODE:

GREEN-AND-YELLOW

: EARTH

BLUE

: NEUTRAL

BROWN

: LIVE

Power Requirements

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

Power Output

1000 W nominal of RF microwave energy (measured by method of IEC 705)
Operating frequency 2450 MHz

Case Dimensions

Width

520 mm

Height

309 mm including foot

Depth

406 mm

Cooking Cavity Dimensions

Width

351 mm

Height

211 mm

Depth

372 mm

Control Complement

Touch Control System
Timer (0 - 99 minutes and 99 seconds)
Microwave Power for Variable Cooking

 Repetition Rate;

P-HI ........................................... Full power throughout the cooking time

P-90 ............................................................. approx. 90% of Full Power
P-80 ............................................................. approx. 80% of Full Power
P-70 ............................................................. approx. 70% of Full Power
P-60 ............................................................. approx. 60% of Full Power
P-50 ............................................................. approx. 50% of Full Power
P-40 ............................................................. approx. 40% of Full Power
P-30 ............................................................. approx. 30% of Full Power
P-20 ............................................................. approx. 20% of Full Power
P-10 ............................................................. approx. 10% of Full Power
P-0 ............................................. No power throughout the cooking time

DOUBLE QUANTITY pad
EXPRESS DEFROST pad
Number pads
SELECT TIME pad
STOP/CLEAR pad
SELECT POWER pad
START pad
SET pad
CHECK pad
SIGNAL pad

Set Weight

Approx. 18 kg