Sharp R-4A56 Service Manual

Page 1

R-4A56

SHARP CORPORATION

SER VICE MANU AL

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

MODEL

R-4A56

S8406R4A56PJZ

MICROWAVE OVEN

TABLE OF CONTENTS

Page

CAUTION, MICROWAVE RADIATION ................................................................................................................ 1

WARNING..............................................................................................................................................................1

PRODUCT SPECIFICATIONS............................................................................................................................. 2

GENERAL INFORMATION ................................................................................................................................... 2

APPEARANCE VIEW........................................................................................................................................... 3

OPERATION SEQUENCE ................................................................................................................................... 4

FUNCTION OF IMPORTANT COMPONENTS .................................................................................................... 5

SERVICING .......................................................................................................................................................... 6

TEST PROCEDURE ............................................................................................................................................ 8

TOUCH CONTROL PANEL ................................................................................................................................ 16

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE............................................................... 20

MICROWAVE MEASUREMENT ........................................................................................................................ 26

WIRING DIAGRAM ............................................................................................................................................. 27

PICTORIAL DIAGRAM....................................................................................................................................... 29

CONTROL PANEL CIRCUIT .............................................................................................................................. 31

PRINTED WIRING BOARD ................................................................................................................................ 32

PARTS LIST........................................................................................................................................................ 33

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R-4A56

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R-4A56

SER VICE MANUAL

PRODUCT SPECIFICATIONS

SHARP CORPORATION

OSAKA, JAPAN

TEST PROCEDURE

SERVICING AND TROUBLESHOOTING CHART

FUNCTION OF IMPORTANT COMPONENTS

OPERATING SEQUENCE

APPEARANCE VIEW

MICROWAVE MEASUREMENT

WIRING DIAGRAM

PARTS LIST

TOUCH CONTROL PANEL ASSEMBLY

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE

MICROWAVE OVEN

R-4A56

GENERAL IMPORTANT INFORMATION

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

DO NOT BECOME EXPOSED TO RADIATION FROM THE MICROWAVE GENERATOR OR OTHER PARTS CONDUCTING MICROWAVE ENERGY.

Service engineers should not be exposed to the microwave energy which may radiate from the magnetron or other microwave 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.

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R-4A56

PRODUCT SPECIFICATIONS

GENERAL INFORMATION

WARNING

THIS APPLIANCE MUST BE EARTHED

IMPOTANT

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

GREEN-AND-YELLOW : EARTH BLUE : NEUTRAL BROWN : LIVE

ITEM DESCRIPTION

Power Requirements 240 Volts (for Australia) / 230 - 240 Volts (for New Zealand)

50 Hertz

Single phase, 3 wire earthed Power Consumption 1.4 kW Power Output 900 watts nominal of RF microwave energy (IEC 705)

750 watts (2 litre water load)

Operating fequency 2450 MHz Case Dimensions Width 550 mm

Height 312 mm

Depth 420 mm Cooking Cavity Dimensions Width 381 mm

Height 210 mm

Depth 411 mm Turntable diameter 360mm Control Complement Touch Control System

Clock ( 1:00 - 12:59)

Timer (0 - 99 minutes 99 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

INSTANT ACTION pads

AUTO COOK pad

EASY DEFROST pad

NUMBER pads

SERVE QUANTITY pads

POWER LEVEL pad

MORE, LESS pads

STOP/CLEAR pad

AUTO START/CLOCK pad

INSTANT COOK/START pad Set Weight Approx. 17 kg

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R-4A56

APPEARANCE VIEW

1. Ventilation openings

2. Oven lamp

3. Door hinges

4. Safety door latches

5. See through door

6. Coupling

7. Door open button

8. Touch control panel

9. Digital readout

10.Wave guide cover

11.Access cover for oven lamp replacement

12.Power supply cord

12345 6789

STOP

CLEAR

AUTO START CLOCK

INSTANT COOK

START

MORE( ), LESS( ) PADS Press to increase/decrease the time in one minute increments during cooking or to alter the doneness for the Auto Cook, Instant Action or  Easy Defrost mode.

AUTO START/CLOCK PAD Press to set clock or Auto Start time.

STOP/CLEAR PAD Press to clear during programming. Press once to stop operation of oven during cooking; press twice to cancel cooking programe.

NUMBER PADS Press to enter cookling times, clock time, weight or quantity of food, or to select the Auto cook menus.

EASY DEFROST PAD Press to defrost meat by entering weight only.

Reheat/Pies/Pastries

1 piece

12345

POWER

LEVEL

EASY

DEFROSTLESSMORE

2 X 3 X 4 X

AUTO COOK PAD Press to select Auto Cook mode.

AUTO COOK MENUS

POWER LEVEL PAD Press to select microwave power setting. If not pressed, HIGH is  automatically selected.

2,3,or 4 SERVE QUANTITY PAD To cook two, three, or four serves, press required pad prior to pressing the Instant Action pad.

INSTANT COOK/START PAD Press once to cook for 1 minute at HIGH  or increase by 1 minute multiples each time  this pad is pressed during cooking.  Press to start oven after setting programmes.

INSTANT ACTION PADS Press once to cook or reheat 8 popular menus.

Rice & Pasta

1/2 uup

1 Fresh Vegetables 2 Frozen Vegetables 3 Jacket Potato 4 Roast Lamb 5 Seasoned Roast 6 Desserts

AUTO

COOK

Frozen 

Dinner

1 serve

Reheat

Beverage/Soup

1 cup

Chicken

Pieces

1 serve Bacon

1 serve

Casseroles

1 serve

Fish Fillets

1 serve

TOUCH CONTROL PANEL

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R-4A56

OPERATION SEQUENCE

OFF CONDITION

Closing the door activates all door interlock switches (Upper latch switch, Lower latch switch and Stop switch)

IMPORTANT When the oven door is closed, the monitor switch contacts (COM-NC) must be open. When the microwave oven is plugged in a wall outlet, rated voltage is supplied to the point (A3+A5) in the control unit.

Figure O-1 on page 27

1. The display flashes “88:88”.

2. To set any programs or set the clock, you must first touch the STOP/CLEAR pad.

3. “ : “ appears in the display and the time counts up every minute.

NOTE: When the oven door is opened, the oven lamp

comes on at this time.

MICROWAVE COOKING CONDITION

HIGH COOKING

Enter a desired cooking time with the touching Number pads and start the oven with touching START pad.

Function sequence

Figure O-2 on page 28

CONNECTED COMPONENTS RELAY Oven lamp, Fan motor, Turntable motor RY1 Power transformer RY2

1. Rated voltage is supplied to the primary winding of the power 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 filament and the high voltage (2000 volts) is sent to the voltage doubling circuit, where it is doubled to negative voltage of approximately 4000 volts D.C..

3. The 2450 MHz microwave energy produced in the magnetron generates 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.

4. When the cooking time is up, a signal tone is heard and the relays (RY1+RY2) go back to their home position. The circuits to the oven lamp, power transformer, fan motor and turntable motor are cut off.

5. 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) Upper latch switches COM-NO Closed Open Lower latch switch COM-NO Closed Open Monitor switch COM-NC Open Closed

Stop switch COM-NO Closed Open

The circuits to the power transformer, fan motor and turntable motor are cut off when the upper latch switch, lower latch switch and stop 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 the remaining time.

6. MONITOR SWITCH CIRCUIT The monitor switch is mechanically controlled by oven door, and monitors the operation of the upper and lower latch switches.

6-1 When the oven door is opened during or after the cycle

of a cooking program, the upper latch switch, lower latch switch and stop switch must open their contacts first. After that the contacts (COM-NC) of the monitor switch can be closed.

6-2. When the oven door is closed, the contacts (COM-NC)

of the monitor switch must be opened first, and the contacts (COM-NO) of the stop switch must be closed. After that the contacts of the upper latch switch, lower latch switch and stop switch are closed.

6-3. When the oven door is opened and the contacts of the

upper latch switch and lower latch switch remain closed. The fuse M8A will blow, because the monitor switch is closed and a short circuit is caused.

VARIABLE COOKING

When the microwave oven is preset for variable cooking

power. Rated voltage is supplied to the power transformer intermittently within a 32-second time base through the relay contact which is coupled with the relay (RY2). The following levels of microwave power are given.

SETTING;

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. 50%

Approx. 30%

Approx. 10%

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

to the percentage of microwave power, because approx. 2 seconds are needed for heating up the magnetron filament.

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R-4A56

FUNCTION OF IMPORTANT COMPONENTS

DOOR OPEN MECHANISM

The door can be opened by pushing the door open button on the control panel. When the door open button is pushed, the latch lever is moved upward, operating the latch head. The latch head is moved upward, and released from the latch hook. Now, the door can be opened.

MONITOR SWITCH

UPPER LATCH SWITCH

STOP SWITCH

LOWER LATCH SWITCH

LATCH LEVER PLUNGER

SWICTH

LATCH HEAD

DOOR OPEN BUTTON

LATCH HEAD

LATCH HOOK

DOOR

Figure D-1. Door Open Mechanism

UPPER LATCH SWITCH, LOWER LATCH SWITCH AND STOP SWITCH

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.

MONITOR SWITCH

1. When the oven door is closed, the contacts (COM- NC) must be opened.

2. When the oven door is opened, the contacts (COM- NC) must be closed.

3. If the oven door is opened and the contacts (COM- NO) of the upper and lower latch switches fail to open, the fuse (M8A) blows simultaneously with closing the contacts (COM-NC) of the monitor switch.

CAUTION: BEFORE REPLACING A BLOWN FUSE (M8A)

TEST THE UPPER AND LOWER LATCH SWITCHES, MONITOR SWITCH AND MONITOR RESISTOR FOR PROPER OPERATION. (REFER TO CHAPTER “TEST PROCEDURE”.)

MONITOR RESISTOR (0.8Ω 20W)

The monitor resistor prevents the fuse (M8A) bursting when the fuse blows due to the operation of the monitor switch.

ASYMMETRIC RECTIFIER

The asymmetric rectifier is a solid state device that prevents current flow in both directions. And it prevents the tempera-

ture rise of the power transformer by blowing the fuse (M8A) when the high voltage rectifier is shorted.

The rated peak reverse voltage of D1 of the asymmetric rectifier is 6 KV The rated peak reverse voltage of D2 of the asymmetric rectifier is 1.7 KV. D1 and D2 of the asymmetric rectifier or high voltage rectifier are shorted when the each peak reverse voltage goes beyond the each rated peak reverse voltage. (The process of blowing the fuse M8A.)

1. The high voltage rectifier is shorted by any causes when microwave cooking.

2. The peak reverse voltage of D2 of the rectifier goes beyond the rated peak reverse voltage 1.7 KV in the voltage doubler circuit.

3. D2 of the rectifier is shorted.

4. The large electric currents flow through the high voltage winding of the power transformer.

5. The large electric currents beyond 8A flow through the primary winding of the power transformer.

6. The fuse (M8A) blows by the large electric currents.

7. The power supply to the power transformer is cut off.

THERMAL CUT-OUT 145˚C (OVEN)

The thermal cut-out located on the top of the oven cavity is designed to prevent damage to the oven if the foods in the oven catch fire due to over heating produced by improper setting of cook time or failure of control unit. Under normal operation, the oven thermal cut-out remains closed. However, when abnormally high temperatures are reached within the oven cavity, the oven thermal cut-out will open at 145˚C, causing the oven to shut down. The thermal cut-out will be close its contacts again when its temperature goes down lower than -20˚C.

FUSE (M8A)

1. If the wire harness or electrical components are shortcircuited, this fuse blows to prevent an electric shock or fire hazard.

2. The fuse blows when the asymmetric rectifier, H.V. rectifier, H.V. wire harness, H.V. capacitor, magnetron or secondary winding of power transformer is shorted.

3. The fuse also blows when upper and lower latch switches remains closed with the oven door open and when the monitor switch closes.

TEMPERATURE FUSE 150˚C (MG)

This fuse protects the magnetron against overheating. If the temperature goes up higher than 150˚C because the fan motor is interrupted, the air inlet duct is blocked or the ventilation openings are obstructed, the fuse blows and puts the oven out of operation. The defective fuse must be replaced with new rated one.

D2 D1

ASYMMETRIC RECTIFIER

HIGH VOLTAGE RECTIFIER

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R-4A56

TURNTABLE MOTOR

The turntable motor drives the turntable roller assembly to rotate the turntable.

FAN MOTOR

The fan motor drives a blade which draws external cool air. This cool air is directed through the air vanes surrounding the magnetron and cools the magnetron. This air is chan-

nelled through the oven cavity to remove steam and vapours given off from the heating foods. It is then exhausted through the exhausting air vents at the oven cavity.

NOISE FILTER (for New Zealand Model)

The noise filter prevents the radio frequency interference that might flow back in the power circuit.

SERVICING

WARNING TO SERVICE PERSONNEL

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 harness.

REMEMBER TO CHECK 3D

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 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 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.

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 microwave timer for two (2) minutes. Set the power level to HIGH and push the START button. 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 carried out

When troubleshooting the microwave oven, it is helpful to follow the Sequence of Operation in performing the checks. Many of the possible causes of trouble will require that a specific test be performed. These tests are given a procedure letter which will be found in the “Test Procedure “section.

TROUBLESHOOTING GUIDE

IMPORTANT: If the oven becomes inoperative because of

a blown fuse M8A in the upper latch switch

- lower latch switch - monitor switch - monitor resistor circuit, check the upper latch switch, lower latch switch, monitor switch and monitor resistor before replacing the fuse M8A.

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R-4A56

MAGNETRON

POWER TRANSFORMER

H.V. RECTIFIER ASSEMBLY

HIGH VOLTAGE CAPACITOR

UPPER LATCH SWITCH

LOWER LATCH SWITCH

STOP SWITCH

MONITOR SWITCH

NOISE FILTER (FOR N.Z.)

MONITOR RESISTOR

TEMPERATURE FUSE

THERMAL CUT-OUT

FAN MOTOR

TURNTABLE MOTOR

FUSE M8A

TOUCH CONTROL PANEL

RELAY (RY-1, RY-2)

FOIL PATERN ON P.W.B.

POWER SUPPLY CORD

OVEN LAMP OR SOCKET

HIGH OLTAGE WIRE

SHORTED WIRE HARNESS

OPENED WIRE HARNESS

WALL OUTLET

HOME FUSE OR BREAKER

WRONG OPERATION

MISADJUSTMENT SWITCH

BLOCKED COOLING FAN

BLOCKED VENTILATION OPENING

Home fuse blows when power supply cord is plugged into wall outlet.

FUSE M8A blows when power supply cord is plugged into wall outlet.

"88:88" does not appear in display but power supply cord is plugged into wall outlet.

Display does not operate properly when STOP/CLEAR pad is touched.

Oven lamp does not light at door opened. (Display appears.)

Oven does not start when the START pad is touched. (Display appears)

Oven lamp does not light (Display appears.)

Fan motor does not operate. (Display appears.)

Turntable motor assembly does not operate. (Display appears.)

Oven or any electrical parts does not stop when cooking time is 0 or STOP/CLEAR pad is touched.

Oven seems to be operating but little or no heat is produced in oven load. (Microwave power level is set at HIGH)

Oven does not seems to be operating properly when MEDIUM HIGH, MEDIUM, MEDIUM LOW or LOW is set. (Oven operates properly at HIGH and then the STOP/ CLEAR pad is touched the oven stops.)

Oven goes into cook cycle but shuts down before end of cooking cycle.

Oven stops as soon as when the START pad is touched.

OFF CONDITION

PROBLEM

CONDITION

POSSIBLE CAUSE

AND

DEFECTIVE PARTS

TEST PROCEDURE

ON CONDITION

CK = Check / RE = Replace

ABCDEEEEFG H H I I JKMNRERE CK CKCKCK CKCKCK CKCK

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R-4A56

TEST PROCEDURES

PROCEDURE

LETTER

CARRY OUT 3D CHECKS.

Isolate the magnetron from high voltage circuit by removing all leads connected to filament terminal. To test for an open circuit filament use an ohmmeter to make a continuity test between the magnetron

filament terminals, the meter should show a reading of less than 1 ohm. To test for short filament to anode condition, connect ohmmeter between one of the filament terminals

and the case of the magnetron (ground). This test should be indicated an infinite resistance. If a low or zero resistance reading is obtained then the magnetron should be replaced.

MICROWAVE OUTPUT POWER (1 Litre water load)

The following test procedure should be carried out with the microwave oven in a fully assembled condition (outer case fitted). Microwave output power from the magnetron can be measured by way of IEC 705, i.e. it can be measured by using water load how much it can be absorbed by the water load. To measure the microwave output power in the microwave oven, the relation of calorie and watt is used. When P(W) heating works for t(second), approximately P x t/4.187 calorie is generated. On the other hand, if the temperature of the water with V(ml) rises ∆T (°C) during this microwave heating period, the calorie of the water is V x ∆T.

NEVER TOUCH ANY PART IN THE CIRCUIT WITH YOUR HAND OR AN INSULATED TOOL WHILE THE OVEN IS IN OPERATION.

A MAGNETRON TEST

The formula is as follows;

P x t / 4.187 = V x ∆ T P (W) = 4.187 x V x ∆T / t

Our condition for water load is as follows:

Room temperature..............around 20°C Power supply Voltage.........Rated voltage

Water load.........1000 g Initial temperature...........10±2°C Heating time.........47 sec.

P = 90 x ∆T

Measuring condition:

1. Container The water container must be a cylindrical borosilicate glass vessel having a maximum material thickness of 3 mm and an outside diameter of approximately 190 mm.

2. Temperature of the oven and vessel The oven and the empty vessel are at ambient temperature prior to the start the test.

3. Temperature of the water The initial temperature of the water is (10±2)°C.

4. Select the initial and final water temperature so that the maximum difference between the final water temperature and the ambient temperature is 5˚C.

5. Select stirring devices and measuring instruments in order to minimize addition or removal of heat.

6. The graduation of the thermometer must be scaled by 0.1°C at minimum and accurate thermometer.

7. The water load must be (1000±5) g.

8. “t” is measured while the microwave generator is operating at full power. Magnetron filament heatup time is not included.

NOTE: The operation time of the microwave oven is “t + 2” sec. 2 sec. is magnetron filament heat-up time.

Measuring method:

1. Measure the initial temperature of the water before the water is added to the vessel. (Example: The initial temperature T1 = 11°C)

2. Add the 1 litre water to the vessel.

3. Place the load on the centre of the shelf.

4. Operate the microwave oven at HIGH for the temperature of the water rises by a value ∆ T of (10 ± 2)˚C.

5. Stir the water to equalize temperature throughout the vessel.

COMPONENT TEST

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R-4A56

TEST PROCEDURES

PROCEDURE

LETTER

COMPONENT TEST

6. Measure the final water temperature. (Example: The final temperature T2 = 21°C)

7. Calculate the microwave power output P in watts from above formula.

Initial temperature.................................................................................................. T1 = 11°C

Temperature after (47 + 2) = 49sec....................................................................... T2 = 21°C

Temperature difference Cold-Warm .................................................................... ∆T1 = 10°C

Measured output power

The equation is “P = 90 x ∆T”....................................................... P = 90 x 10°C = 900 Watts

JUDGMENT: The measured output power should be at least ± 15 % of the rated output power.

CAUTION: 1°C CORRESPONDS TO 90 WATTS REPEAT MEASUREMENT IF THE POWER IS

INSUFFICIENT.

1000g

T1˚C

T2˚C

Heat up for 49 sec.

MICROWAVE OUTPUT POWER (2 Litre water load)

The following test procedure should be carried out with the microwave oven in a fully assembled condition (with outer case fitted). Microwave output power from the magnetron can be measured by way of substitution, i.e. it can be measured by using a water load how much it can be absorbed by the water load. To measure the microwave output power in the microwave oven, the relation of calorie and watt is used. On the other hand, if the temperature of the water with V(ml) rises ∆T (˚C) during this microwave heating period, the calorie of the water is V x ∆T.

The formula is as follows;

P = 8330 x ∆ T/t

Our condition for water load is as follows:

Room temperature..............23±2˚C Power supply Voltage.........Rated voltage

Water load.........2000 ml Initial temperature...........23±1˚C Heating time .1 min. 51sec.

P = 75 x ∆T

Measuring method: A) The two water containers must be prepared.

The water container must be one (1) litre beaker made of Pyrex glass and its diameter approximately 12cm.

B) Put the one (1) litre water into each beaker (Each beaker has one litre water). The initial temperature

of the water should be 23±1˚C.

C) Mark T1 on the one beaker and mark T2 on the other one. And stir the water and measure the

temperature of water the thermometer and note them. The graduation of the thermometer must be

scaled by 0.1˚C at minimum and an accurate mercury thermometer is recommended. D) Place the two (2) beakers as touching each other in the centre of the oven cavity. E) Set the timer to 1 minutes and 51 seconds, start the oven at 100% power. F) The time must be measured with stopwatch or wristwatch. G) After 1 minutes and 51 seconds, stop the oven by opening the door. H) Put the two (2) beakers out of the oven cavity and measure the temperature of the water by stirring

the water with thermometer and note them.

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TEST PROCEDURES (CONT'D)

B POWER TRANSFORMER TEST

WARNING: High voltages and large currents are present at the secondary winding and filament

winding of the transformer. It is very dangerous to work near this part when the oven is on. NEVER make any voltage measurements of the high-voltage circuits, including the magnetron filament.

CARRY OUT 3D CHECKS.

Disconnect the leads to the primary winding of the power transformer. Disconnect the filament and secondary winding connections from the rest of the HV circuitry. Using an ohmmeter, set on a low range, it is possible to check the continuity of all three windings. The following readings should be obtained:

a. Primary winding ................... approx. 1.54 Ω

b. Secondary winding............... approx. 84.8 Ω

c. Filament winding .................. less than 1Ω

If the reading obtained are not stated as above, then the power transformer is probably faulty and should be replaced.

CARRY OUT 4R CHECKS.

C HIGH VOLTAGE RECTIFIER ASSEMBLY TEST

HIGH VOLTAGE RECTIFIER TEST CARRY OUT 3D CHECKS. Isolate the high voltage rectifier assembly from the HV circuit. The high voltage rectifier can be tested using an ohmmeter set to its highest range. Connect the ohmmeter across the terminal B+C of the high voltage rectifier and note the reading obtained. Reverse the meter leads and note this second reading. The normal resistance is infinite in one direction and more than 100 kΩ in the other direction.

Example

Initial temperature .............................................................................T1 = 23˚C T2 = 24˚C

Temperature after 1 min. 51 sec. ..................................................... T1 = 33˚C T2 = 34˚C

Temperature difference Cold-Warm.............................................. ∆T1 = 10˚C ∆T2 = 10˚C

Mean temperature rise ∆T.........................∆T = (∆T1 ± ∆T2) / 2 = (10˚C+10˚C) / 2 = 10˚C

Measured output power

The equation is P= 75 x ∆T ......................................................... P= 75 x 10˚C =750 Watts

NOTE: The measured output power should be at least ± 15 % of the rated output power.

CAUTION: 1˚C CORRESPONDS TO 75 WATTS. REPEAT MEASUREMENT IF THE POWER IS

INSUFFICIENT.

COMPONENT TEST

PROCEDURE

LETTER

1 l 1 l

(T1 C) (T2 C)

1 l 1 l

(T1 C) (T2 C)

Heat up for 1min. 51 sec.

1 litre

1 litre 1 litre

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R-4A56

TEST PROCEDURES (CONT'D)

CARRY OUT

4R CHECKS. ASYMMETRIC RECTIFIER TEST CARRY OUT

3D CHECKS.

Isolate the high voltage rectifier assembly from the HV circuit. The asymmetric can be tested using an ohmmeter set to its highest range across the terminals A+B of the asymmetric rectifier and note the reading obtained. Reverse the meter leads and note this second reading. If an open circuit is indicated in both direction then the asymmetric rectifier is good. If an asymmetric rectifier is shorted in either direction, then the asymmetric rectifier is probably faulty and must be replaced with high voltage rectifier. When the asymmetric rectifier is defective, check whether magnetron, high voltage rectifier, high voltage wire or filament winding of the power transformer is shorted.

CARRY OUT 4R CHECKS. NOTE: FOR MEASUREMENT OF THE RESISTANCE OF THE RECTIFIER, THE BATTERIES OF THE

MEASURING INSTRUMENT MUST HAVE A VOLTAGE AT LEAST 6 VOLTS, BECAUSE OTHERWISE AN INFINITE RESISTANCE MIGHT BE SHOWN IN BOTH DIRECTIONS.

PROCEDURE

LETTER

COMPONENT TEST

D2 D1

ASYMMETRIC RECTIFIER

HIGH VOLTAGE RECTIFIER

D HIGH VOLTAGE CAPACITOR TEST

CARRY OUT 3D CHECKS. A. Isolate the high voltage capacitor from the circuit.

B. Continuity check must be carried out with measuring instrument which is set to the highest resistance

range.

C. A normal capacitor shows continuity for a short time (kick) and then a resistance of about 10MΩ after it has

been charged. D. A short-circuited capacitor shows continuity all the time. E. An open capacitor constantly shows a resistance about 10 MΩ because of its internal 10MΩ resistance. F. When the internal wire is opened in the high voltage capacitor shows an infinite resistance. G. The resistance across all the terminals and the chassis must be infinite when the capacitor is normal. If incorrect reading are obtained, the high voltage capacitor must be replaced.

CARRY OUT

4R CHECKS.

E SWITCH TEST

CARRY OUT 3D CHECKS. Isolate the switch to be tested and using an ohmmeter check between the terminals as described in the

following table.

Table: Terminal Connection of Switch

Plunger Operation COM to NO COM to NC

Released O.C. S.C. Depressed S.C. O.C.

COM; Common terminal, NO; Normally open terminal NC; Normally close terminal S.C.; Short circuit O.C.; Open circuit

If incorrect readings are obtained, make the necessary switch adjustment or replace the switch. CARRY OUT

4R CHECKS.

F NOISE FILTER TEST

CARRY OUT 3D CHECKS. Disconnect the leads from the terminals of the noise

filter. Using an ohmmeter, check between the terminals as described in the following table.

L (min) Cx ± 20% Cy ± 20%

1.0 mH 0.068µF 2200pF

If incorrect readings are obtained, replace the noise filter unit.

CARRY OUT 4R CHECKS.

MEASURING POINT INDICATION OF OHMMETER Between N and L Open circuit Between terminal N and WHITE Short circuit

Between terminal L and RED Short circuit

M8A

RED

WHT

Page 14

R-4A56

PROCEDURE

LETTER

COMPONENT TEST

TEST PROCEDURES (CONT'D)

G MONITOR RESISTOR TEST

CARRY OUT 3D CHECKS. Disconnect the leads from the monitor resist. Using an ohmmeter and set on a low range. Check between

the terminals of the monitor resistor.

The resistance of monitor resistor is approx. 0.8 ohms. If incorrect readings are obtained, replace the monitor resistor. CARRY OUT 4R CHECKS.

H TEMPERATURE FUSE OR THERMAL CUT-OUT TEST

CARRY OUT 3D CHECKS.

Disconnect the leads from the terminals of the temperature fuse or thermal cut-out. Then using an

ohmmeter, make a continuity test across the two terminals as described in the table below.

CARRY OUT 4R CHECKS

.Table: Thermal cut-out Test

Temperature of "ON" condition Temperature of "OFF" condition Indication ofohmmeter

Parts Name (closed circuit) (˚C) (open circuit) (˚C) (When room temperature

is approx. 20˚C) Thermal cut-out 145˚C -20˚C Above 145˚C Closed circuit. Temperature fuse 150˚C This is not resetable type Above 150˚C Closed circuit.

If incorrect readings are obtained, replace the temperature fuse or thermal cut-out. An open circuit temperature fuse 150˚C (MG) indicates that the magnetron has overheated, this may be

due to restricted ventilation, cooling fan failure or a fault condition within the magnetron or HV circuit. An open circuit thermal cut-out 145˚C (OVEN) indicates that the foods in the oven may catch fire, this

may be due to over heating produced by improper setting of the cooking time or failure of the control panel.

CARRY OUT 3D CHECKS.

Disconnect the leads from the motor.

Using an ohmmeter, check the resistance between the two terminals as described in the table below.

I MOTOR WINDING TEST

Table: Resistance of Motor Motors Resistance Fan motor Approximately 295 Ω Turntable motor Approximately 12.5 kΩ

If incorrect readings are obtained, replace the motor. CARRY OUT 4R CHECKS.

LIVE TEST FOR MOTOR WINDINGS

CAUTION: THE FOLLOWING PROCEDURE REQUIRES THE OVEN TO BE CONNECTED TO THE

SUPPLY AND SHOULD ONLY BE USED IF THE RELEVANT “COLD” CHECKS FOR THE MOTOR UNDER TEST ARE INCONCLUSIVE.

1. CARRY OUT 3D CHECKS.

2. Disconnect the leads from the primary of the power transformer. Make sure that the leads remain isolated from other oven components and chassis. (Use insulation tape if necessary.)

3. Connect a voltmeter, set to 250V AC, across the motor terminals. (Refer to the relevant motor test procedure or pictorial diagram for the correct terminal numbers.)

4. Arrange the meter in a position where it can be read during the test. (Do not touch the meter, meter leads or oven circuitry while the oven is active.)

Page 15

R-4A56

TEST PROCEDURES (CONT'D)

PROCEDURE

LETTER

COMPONENT TEST

5. Close the oven door.

6. Set the power level to HIGH and set the relevant timer for about three (3) minutes.

7. Note the reading on the meter and carefully observe the motor under test to see if it is turning.

8. CARRY OUT 3D CHECKS.

9. Remove test meter leads.

10.Reconnect the leads to the primary of the power transformer. If a reading of the line voltage was obtained (step 7) but the motor was not turning then it is faulty and

should be replaced. If the meter indicated that no supply was present then the wiring to the motor should be checked for continuity.

J BLOWN FUSE F M8A

CARRY OUT 3D CHECKS.

1. If the fuse M8A is blown, there could be shorts or ground in electrical parts or wire harness. Check them and replace the defective parts or repair the wire harness.

2. If the fuse M8A is blown when the door is opened, check the upper latch switch, lower latch switch, monitor switch and monitor resistor. If the fuse M8A is blown by incorrect door switching replace the defective switch(s) and the fuse M8A.

3. If the fuse M8A is blown, there could be a short in the asymmetric rectifier or there could be a ground in wire harness. A short in the asymmetric rectifier may have occurred due to short or ground in H.V. rectifier, magnetron, power transformer or H.V. wire. Check them and replace the defective parts or repair the wire harness.

CARRY OUT 4R CHECKS. CAUTION: ONLY REPLACE FUSE M8A WITH THE CORRECT VALUE REPLACEMENT

The touch control panel consists of circuits including semiconductors such as LSI, ICs, etc. Therefore, unlike conventional microwave ovens, proper maintenance cannot be performed with only a voltmeter and ohmmeter. In this service manual, the touch control panel assembly is divided into two units, Control Unit and Key Unit, and troubleshooting by replacement is described according to the symptoms indicated.

1. Key Unit. The following symptoms indicate a defective key unit. Replace the key unit.

a) When touching the pads, a certain pad produces no signal at all. b) When touching a number pad, two figures or more are displayed. c) When touching the pads, sometimes a pad produces no signal.

2. Control Panel The following symptoms indicate a defective control unit. Replacing the control unit.

2-1 In connection with pads.

a) When touching the pads, a certain group of pads do not produce a signal. b) When touching the pads, no pads produce a signal.

2-2 In connection with indicators

a) At a certain digit, all or some segments do not light up. b) At a certain digit, brightness is low. c) Only one indicator does not light. d) The corresponding segments of all digits do not light up; or they continue to light up. e) Wrong figure appears. f) A certain group of indicators do not light up. g) The figure of all digits flicker.

2-3 Other possible troubles caused by defective control unit.

a) Buzzer does not sound or continues to sound. b) Clock does not operate properly. c) Cooking is not possible. d) Proper temperature measurement is not obtained.

K TOUCH CONTROL PANEL ASSEMBLY TEST

Page 16

R-4A56

TEST PROCEDURES (CONT'D)

PROCEDURE

LETTER

COMPONENT TEST

If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the ribbon is making good contact, verify that the door sensing switch(stop switch) operates properly; that is the contacts are closed when the door is closed and open when the door is open. If the door sensing switch(stop switch) is good, disconnect the flat ribbon that connects the key unit to the control unit and make sure the door sensing switch is closed (either close the door or short the stop switch connecter). Use the Key unit matrix indicated on the control panel schematic and place a jumper wire between the pins that correspond to the STOP/CLEAR pad making momentary contact. If the control unit responds by clearing with a beep the key unit is faulty and must be replaced. If the control unit does not respond, it is a faulty and must be replaced. If a specific pad does not respond, the above method may be used (after clearing the control unit) to determine if the control unit or key pad is at fault.

L KEY UNIT TEST

KEY UNIT

STOP

CLEAR

POWER

LEVEL

G-12

G-11

G-10

G-9

G-8

G-7

G-6

G-5

G-4

G-3

G-2

G-1

LESS

234

890

AUTO COOK

AUTO START CLOCK

EASY

DEFROST

Reheat

Beverage

/Soup

INSTANT

COOK START

Rice

Pasta

Frozen Dinner

4 X

3 X 2 X

Bacon

Casseroles

Chicken

Pieces

Reheat

Pie/

Pastries

Fish

Fillets

M RELAY TEST

1. CARRY OUT 3D CHECKS.

2. Disconnect the leads from the primary of the power transformer, Make sure that the leads remain isolated from other oven components and chassis. (Use insulation tape if necessary)

3. Close the door.

4. Reconnect the supply.

5. Check the voltage between Pin Numbers 3 and 5 of 3-pin connector (A) on the control unit with an A.C. voltmeter. The meter should indicated 240 volts, if no cheak oven circuit.

6. RY1 AND RY2 Test These are operated by D.C. voltage. Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking.

DC. voltage indicated ................... Defective relay.

DC. voltage not indicated ................Check diode which is connected to the relay coil. If diode is

good, control unit is defective.

RELAY SYMBOL OPERATIONAL VOLTAGE CONNECTED COMPONENTS

RY1 APPROX. 26.5V D.C. Oven lamp / Turntable motor / Cooling fan motor RY2 APPROX. 25.8V D.C. Power transformer

Page 17

R-4A56

TEST PROCEDURES (CONT'D)

PROCEDURE

LETTER

COMPONENT TEST

N PROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED WIRING BOARD

(PWB) IS OPEN

To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary on the PWB, this foil pattern acts as a fuse. If the foil pattern is open, follow the troubleshooting guide given below for repair.

Problem: POWER ON, indicator does not light up.

NOTE: At the time of these repairs, make a visual

inspection of the varistor for burning damage and examine the transformer with tester for the presence of layer short-circuit (check primary coil resistance). If any abnormal condition is detected, replace the defective parts.

CARRY OUT 4R CHECKS.

RY2

US:RED,CD:GRY GE:BLK,AS:BRN

D32

(TAB1) (COM.)

(TAB2)

(H.V.)

(J1)

VRS1

D31

(H.V.)

POWER

O.L.,F.M.,T.T.M.,

CN–A

RY1

5731

STEPS OCCURANCE CAUSE OR CORRECTION

1 The rated voltage is not applied to POWER Check supply voltage and oven main unit.

terminal of CPU connector (CN-A).

2 The rated voltage is applied to primary side Low voltage transformer or secondary circuit defective.

of low voltage transformer. Check and repair.

3 Only pattern at "a" is broken. *Insert jumper wire J1 and solder.

(CARRY OUT

3D CHECKS BEFORE REPAIR)

4 Pattern at "a" and "b" are broken. *Insert the coil RCILF2003YAZZ between "c" and "d".

(CARRY OUT 3D CHECKS BEFORE REPAIR)

Page 18

R-4A56

TOUCH CONTROL PANEL ASSEMBLY

OUTLINE OF TOIUCH CONTROL PANEL

3) Synchronizing Signal Circuit

This power source synchronizing signal is available in order to compose a basic standard time in the clock circuit. It accompanies a very small error because it works on commercial frequency.

4) ACL Circuit

A circuit to generate a signals which resets the LSI to the initial state when power is supplied.

5) Buzzer Circuit

The buzzer is responsive to signals from the LSI to emit noticing sounds (key touch sound and completion sound).

6) Door Sensing Switch

A switch to “tell” the LSI if the door is open or closed.

7) Relay Circuit

To drive the magnetron, fan motor, turntable motor and light the oven lamp.

8) Indicator Circuit

Indicator element is a Fluorescent Display. Basically, a Fluorescent Display is triode having a cathode, a grid and an anode. Usually, the cathode of a Fluorescent Display is directly heated and the filament serves as cathode. The Fluorescent Display has 6-digits, 13-segments are used for displaying figures.

The touch control section consists of the following unit as shown in the touch control panel circuit.

(1) Key Unit (2) Control Unit

The principal functions of these units and the signals communicated among them are explained below.

Key Unit

The key unit is composed of a matrix, signals generated in the LSI are sent to the key unit through R00-R03,R10-R13. When a key pad is touched, a signal is completed through the key unit and passed back to the LSI through R23,R30R32 to perform the function that was requested.

Control Unit

Control unit consists of LSI, power source circuit, synchronizing signal circuit, ACL circuit, buzzer circuit and indicator circuit.

1) LSI

This LSI controls the key strobe signal, relay driving signal for oven function and indicator signal.

2) Power Source Circuit

This circuit generates voltages necessary in the control unit.

Symbol Voltage Application VC -5V LSI(IC1) VP -29V Fluorescent display tube : Grid

and anode voltage

VF1 3Vac Filament of fluorescent display

tube

VF2 (VF1 to VF2 voltage)

Page 19

R-4A56

DESCRIPTION OF LSI

LSI(IZA430DR)

The I/O signal of the LSI(IZA430DR) is detailed in the following table.

Pin No. Signal I/O Description

1 D10 OUT Digit selection signal.

Refer to the touch control panel circuit about the relation between signals and digits. Normally, one pulse is output in every synchronized signal period, and input to the grid of the fluorescent display.

2 D11 OUT Segment data signals.

Refer to the touch control panel circuit for the relationship between signals and indicators. Normally, one pulse is output in every synchronized signal period, and input to the anode of the fluorescent display.

3 TG1 OUT Signal to sound buzzer.

A: key touch sound (0.12sec.). B: Completion sound (2.4sec.).

4 Vdisp IN Anode (segment) of Fluorescent Display illumination voltage:-29V.

Vp voltage of power source circuit input.

5R00OUT Segment data signal.

Signal similar to D11.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R23,R30-R32 terminal while one of G1 line keys on key matrix is touched.

6R01OUT Segment data signal.

Signal similar to D11.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R23,R30-R32 terminal while one of G2 line keys on key matrix is touched.

7R02OUT Segment data signal.

Signal similar to D11.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R23,R30-R32 terminal while one of G3 line keys on key matrix is touched.

8R03OUT Segment data signal.

Signal similar to D11.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R23,R30-R32 terminal while one of G4 line keys on key matrix is touched.

9R10OUT Segment data signal.

Signal similar to D11.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R23,R30-R32 terminal while one of G5 line keys on key matrix is touched.

10 R11 OUT Segment data signal.

Signal similar to D11.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R23,R30-R32 terminal while one of G6 line keys on key matrix is touched.

11 R12 OUT Segment data signal.

Signal similar to D11.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R23,R30-R32 terminal while one of G7 line keys on key matrix is touched.

12 R13 OUT Segment data signal.

Signal similar to D11.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R23,R30-R32 terminal while one of G8 line keys on key matrix is touched.

13-15 R20-R22 OUT Segment data signal.

Signal similar to D11.

Page 20

R-4A56

Pin No. Signal I/O Description

16 R23 IN Signal coming from touch key.

When either one of G9 line keys on key matrix is touched, a corresponding signal out of R00-R03, R10-R13 will be input into R23. When no key is touched, the signal is held at "L" level.

17 R30 IN Signal coming from touch key.

When either one of G10 line keys on key matrix is touched, a corresponding signal will be input into R30.

18 R31 IN Signal coming from touch key.

When either one of G11 line keys on key matrix is touched, a corresponding signal will be input into R31.

19 R32 IN Signal coming from touch key.

When either one of G12 line keys on key matrix is touched, a corresponding signal will be input into R32.

20 INT1 IN Signal synchronized with commercial source frequency(50Hz).

This is basic timing for time processing of LSI.

21 GND IN Power source voltage : -5V.

VC voltage of power source circuit input. 22 AVCC IN Connected to GND. 23-24 AN0-AN1 IN Connected to VC. 25 AN2 IN Terminal to used. 26 AN3 IN Input signal which communicates the door open/close information to LSI..

Door closed; "H" level signal.

Door opened; "L" level signal. 27 AVSS IN Connected to VC. 28 RESET IN Auto clear terminal.

Signal is input to reset the LSI to the initial state when power is supplied. Temporarily

set to “H” level the moment power is supplied, at this time the LSI is set. Thereafter

set at “L” level. 29 TEST IN Connected to GND. 30 OSC1 IN Internal clock oscillation frequency input setting.

The internal clock frequency is set by inserting the ceramic filter oscillation circuit with

respect to OSC1 terminal. 31 OSC2 OUT Internal clock oscillation frequency control output.

Output to control oscillation input of OSC2. 32 VCC IN Power source voltage input terminal.

Connected to GND. 33 D0 OUT Terminal to used. 34 D1 OUT Magnetron High-voltage circuit driving signal.

To turn on and off the cook relay). In HIGH operation, the signals holds “H” level during

microwave cooking and “L” level while not cooking. In other cooking modes (MED

HIGH,MED,MED LOW,LOW) the signal turns to “H” level and “L” level in repetition

according to the power level. 35 D2 OUT Terminal not used. 36 D3 OUT Oven lamp, turntable motor and cooling fan motor driving signal. (Square

Waveform : 45Hz)

To turn on and off the control relay. The pulse signal (45Hz) is delivered to the control

relay driving circuit and cook relay control circuit. 37 D4 OUT Segment data signal.

Signal similar to D11. 38-42 D5-D9 OUT Digit selection signal.

Signal similar to D10.

Page 21

R-4A56

SERVICING

1. Precautions for Handling Electronic Components

This unit uses CMOS LSI in the integral part of the circuits. When handling these parts, the following precautions should be strictly followed. CMOS LSI have extremely high impedance at its input and output terminals. For this reason, it is easily influenced by the surrounding high voltage power source, static electricity charge in clothes, etc, and sometimes it is not fully protected by the built-in protection circuit. In order to protect CMOS LSI.

1) When storing and transporting, thoroughly wrap them in aluminium foil. Also wrap all PW boards containing them in aluminium foil.

2) When soldering, ground the technician as shown in the figure and use grounded soldering iron and work table.

2. Shapes of Electronic Components

3. Servicing of Touch Control Panel

We describe the procedures to permit servicing of the touch control panel of the microwave oven and the precautions you must take when doing so. To perform the servicing, power to the touch control panel is available either from the power line of the oven itself or from an external power source.

(1)Servicing the touch control panel with power supply

from the oven proper: CAUTION: THE HIGH VOLTAGE TRANSFORMER OF THE MICROWAVE OVEN IS STILL ALIVE TO GIVE YOU DANGER DURING SERVICING:

Therefore, when checking the performance of the touch control panel, put the outer cabinet on the oven to avoid touching the high voltage transformer, or unplug the primary terminal (connector) of the high voltage transformer to turn it off; the end of such connector must be insulated with an insulating tape. After servicing, be sure to replace the leads to their original locations.

A. On some models, the power supply cord between the

touch control panel and the oven itself is so short that the two can’t be separated. For those models, check and

approx. 1M ohm

repair all the controls (sensor-related ones included) of the touch control panel while keeping it connected to the oven.

B. On some models, the power supply cord between the

touch control panel and the oven proper is long enough that they may be separated from each other. For those models, therefore, it is possible to check and repair the controls of the touch control panel while keeping it apart from the oven proper; in this case you must short both ends of the door sensing switch (on PWB) of the touch control panel with a jumper, which brings about an operational state that is equivalent to the oven door being closed. As for the sensor-related controls of the touch control panel, checking them is possible if dummy resistor(s) with resistance equal to that of the controls are used.

(2) Servicing the touch control panel with power supply

from an external power source:

Disconnect the touch control panel completely from the oven proper,and short both ends of the door sensing switch (on PWB) of the touch control panel,which brings about an operational state that is equivalent to the oven door being closed. Connect an external power source to the power input terminal of the touch control panel, then it is possible to check and repair the controls of the touch control panel it is also possible to check the sensorrelated controls of the touch control panel by using the dummy resistor(s).

4. Servicing Tools

Tools required to service the touch control panel assembly.

1) Soldering iron: 30W (It is recommended to use a soldering iron with a grounding terminal.)

2) Oscilloscope: Single beam, frequency range: DC-10MHz type or more advanced model.

3) Others: Hand tools

5. Other Precautions

1) Before turning on the power source of the control unit, remove the aluminium foil applied for preventing static electricity.

2) Connect the connector of the key unit to the control unit being sure that the lead wires are not twisted.

3) After aluminium foil is removed, be careful that abnormal voltage due to static electricity etc. is not applied to the input or output terminals.

4) Attach connectors, electrolytic capacitors, etc. to PWB, making sure that all connections are tight.

5) Be sure to use specified components where high precision is required.

Transistor DTA114ES DTA143ES DTC143ES DTD143ES

Page 22

R-4A56

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE

WARNING: Avoid possible exposure to microwave energy. Please follow the instructions below before

operating the oven.

1. Door does not close firmly.

2. Door hinge, support or latch hook is damaged.

3. The door gasket or seal or damaged.

4. The door is bent or warped.

5. There are defective parts in the door interlock system.

6. There are defective parts in the microwave generating and transmission assembly.

7. There is visible damage to the oven.

Do not operate the oven:

1. Without the RF gasket (Magnetron).

2. If the wave guide or oven cavity are not intact.

3. If the door is not closed.

4. If the outer case (cabinet) is not fitted.

1. Disconnect the oven from the power supply.

2. Make sure that a definite” click” can be heard when the microwave oven door is unlatched. (Hold the door in a closed position with one hand, then push the door open button with the other, this causes the latch leads to rise, it is then possible to hear a “click’ as the door switches operate.)

3. Visually check the door and cavity face plate for damage (dents, cracks, signs of arcing etc.).

Carry out any remedial work that is necessary before operating the oven. Do not operate the oven if any of the following conditions exist;

Please refer to ‘OVEN PARTS, CABINET PARTS, DOOR PARTS’, when carrying out any of the following removal procedures:

1. CARRY OUT 3D CHECKS.

2. Remove the fan motor assembly from the oven referring to “FAN MOTOR REPLACEMENT”.

3. Disconnect the filament lead of the power transformer from high voltage capacitor.

4. Disconnect the filament lead of the power transformer from the magnetron.

OUTER CASE REMOVAL

To remove the outer case, proceed as follows.

1. Disconnect oven from power supply.

2. Open the oven door and wedge it open.

3. Remove the screws from rear and along the side edge of case.

4. Slide the entire case back about 1 inch (3 cm) to free it from retaining clips on the cavity face plate.

5. Lift the entire case from the oven.

6. Discharge the H.V. capacitor before carrying out any further work.

7. Do not operate the oven with the outer case removed.

N.B.; Step 1,2 and 6 from the basis of the 3D checks. CAUTION: DISCHARGE HIGH VOLTAGE CAPACITOR

BEFORE TOUCHING ANY OVEN COMPONENTS OR WIRING.

POWER TRANSFORMER REMOVAL

5. Disconnect the high voltage wire of H.V. rectifier assembly from the power transformer.

6. Remove the one (1) screw from under side and two (2) screws from upper side holding the transformer to bottom plate.

7. Remove the transformer.

HIGH VOLTAGE COMPONENTS REMOVAL

(High Voltage Capacitor and High Voltage Rectifier Assembly)

from the high voltage capacitor.

7. Disconnect high voltage wire A and terminals of high voltage rectifier assembly from high voltage capacitor.

8. Now high voltage rectifier assembly and capacitor should be free.

CAUTION: WHEN REPLACING HIGH VOLTAGE RECTI-

FIER ASSEMBLY, ENSURE THAT THE CATHODE (EARTH) CONNECTION IS SECURELY FIXED TO THE CAPACITOR HOLDER WITH AN EARTHING SCREW.

To remove the components, proceed as follows.

1. CARRY OUT 3D CHECKS.

2. Disconnect the high voltage wire A from the magnetron.

3. Disconnect the filament lead (shorter one) of the power transformer.

4. Disconnect the high voltage wire of the H.V. rectifier assembly from the high voltage capacitor.

5. Remove one (1) screw holding capacitor holder to the oven cavity.

6. Remove one (1) screw holding earth side terminal of high voltage rectifier assembly, and remove capacitor holder

1. CARRY OUT 3D CHECKS.

2. Disconnect the H.V. wire A and filament lead (longer

MAGNETRON REMOVAL

one) of the transformer from the magnetron.

3. Release the main harness from the tabs of the air duct.

Page 23

R-4A56

REMOVAL

1. CARRY OUT 3D CHECKS.

2. Disconnect the wire leads from the fan motor.

3. Disconnect the H.V. wire A and the filament lead (longer one) of the power transformer from the magnetron.

4. Release the H.V. wire A and filament lead from the holes in the fan duct.

5. Remove the snap band of the wire leads connected to the oven lamp from the hole of the oven cavity.

6. Remove the one (1) screw holding the magnetron air guide to the oven cavity and remove the magnetron air guide.

7. Release the tabs of the fan duct from the holes in the bottom plate and the back plate of the oven cavity.

8. Release the main wire harness from the hole in the fan duct.

9. Now, the fan motor assembly is free.

10.Remove the fan blade from the fan motor shaft according the following procedure.

1) Hold the edge of the rotor of the fan motor by using a pair of groove joint pliers.

4. Remove the air duct from the oven cavity.

5. Carefully remove four (4) screws holding magnetron to waveguide, when removing the screws holding the magnetron to prevent it fro falling.

6. Remove the magnetron from the waveguide with care so the magnetron antenna should not hit by any metal object around the antenna

7. Remove the magnetron cushion from the magnetron. CAUTION: WHEN REPLACING THE MAGNETRON, BE

SURE THE R.F. GASKET IS IN PLACE AND THE MAGNETRON MOUNTING SCREWS ARE TIGHTENED SECURELY.

OVEN LAMP AND LAMP SOCKET REMOVAL

1. CARRY OUT 3D CHECKS.

2. Remove the snap of the wire tie holding the wire leads to the oven lamp from the hole of the oven cavity.

3. Remove the one (1) screw holding the magnetron air guide to the oven cavity.

4. Lift up the tab holding the oven lamp socket.

5. Remove the oven lamp socket.

6. Pull the wire leads from the oven lamp socket by pushing the terminal hole of the oven lamp socket with the flat type small screw driver.

7. Now, the oven lamp socket is free.

Oven lamp socket

Terminal

Wire lead

Flat type small  screw driver

Terminal hole

Figure C-1 Oven lamp socket

5. Remove the two (2) screws holding the turntable motor to oven cavity bottom side and remove the turntable motor.

6. Turntable motor is now free. At this time, o-ring and washer is removed. Do not loose them.

TURNTABLE MOTOR REMOVAL

1. Disconnect the oven from power supply.

2. Remove the turntable and roller stay from the oven cavity.

3. Remove the one (1) screw holding the turntable motor cover to the bottom plate and remove the cover.

4. Disconnect the wire leads from turntable motor.

TURNTABLE COUPLING REMOVAL

1. Remove the turntable motor, refer to “Turntable Motor Removal”.

2. At the time turntable coupling will be free.

TURNTABLE COUPLING

BOTTOM  OVEN CAVITY

T.T. MOTOR ANGLE

Figure C-2. Turntable Coupling

FAN MOTOR REPLACEMENT

CAUTION: * Make sure that any pieces do not enter the gap

between the rotor and the stator of the fan motor. Because the rotor is easy to be shaven by pliers and metal pieces may be produced.

* Do not touch the pliers to the coil of the fan motor

because the coil may be cut or injured.

* Do not transform the bracket by touching with the

pliers.

2) Remove the fan blade assembly from the shaft of the fan motor by pulling fan retainer clip and rotating the fan blade with your hand.

3) Now, the fan blade will be free.

CAUTION: * Do not use this removed fan blade again. Because

the hole (for shaft) of it may become bigger than a standard one.

11.Remove the two (2) screws and nuts holding the fan motor to the fan duct.

12.Now, the fan motor is free.

Page 24

R-4A56

3) Install the fan blade to the shaft of fan motor by pushing the fan blade with a small, light weight, ball peen hammer or rubber mallet.

CAUTION: * Do not hit the fan blade strongly when installed

because the bracket may be transformed.

* Make sure that the fan blade rotates smooth after

installed.

* Make sure that the axis of the shaft is not slanted.

3. Re-install the main wire leads into the hole in the fan duct.

4. Re-install the fan duct to the oven cavity.

5. Re-install the magnetron air guide to the oven cavity with one (1) screw.

6. Re-install the snap band of the wire leads to the oven lamp to the hole of the oven cavity.

7. Re-install the H.V. wire A and filament lead into the holes in the fan duct and then re-connect them to the magnetron, referring to the pictorial diagram.

8. Re-connect the wire leads to the fan motor, referring to the pictorial diagram.

INSTALLATION

1. Install the fan motor to the fan duct with the two (2) screws and nuts.

2. Install the fan blade to the fan motor shaft according the following procedure.

1) Hold the centre of the bracket which supports the shaft of the fan motor on the flat table.

2) Apply the screw lock tight into the hole (for shaft) of the fan blade.

Coil

Gap

Rotor

Bracket

Stator

Groove joint pliers

Rear view

Shaft

Axis

Stator

These are the position where should be pinched with pliers

Rotor

Side view

POSITIVE LOCK® CONNECTOR REMOVAL

1. Pushing the lever of positive lock® connector.

2. Pull down the connector from the terminal.

3. Now, the connector is free.

Note: If the positive lock® has a insulation sleeve, first

remove it. If you do not so, you can not push the lever of positive lock®.

CAUTION: THE POSITIVE LOCK® TERMINAL CAN NOT

BE DISCONNECTED BY ONLY PULLING. BECAUSE ONCE YOU (SERVICE PERSONAL) HAVE CONNECTED THE POSITIVE LOCK® CONNECTOR TO THE TERMINAL, THE POSITIVE LOCK® CONNECTOR HAS BEEN LOCKED.

Terminal

Push

Pull down

Lever

Positive lock® connector

Figure C-3. Positive lock® connector

1. CARRY OUT 3D CHECKS.

2. Disconnect the main harness and low voltage harness from the control panel.

3. Remove the single (1) screw holding the control panel to the oven cavity.

4. Lift up the control panel assembly and pull it forward. Now, the control panel assembly is free.

NOTE: 1. Before attaching a new key unit, remove remaining

CONTROL PANEL ASSEMBLY REMOVAL

adhesive on the control panel frame surfaces completely with alcohol and so on.

2. When attaching the key unit to the control panel frame, adjust the upper edge and right edge of the key unit to the correct position of control panel frame.

3. Stick the key unit firmly to the control panel frame by rubbing with soft cloth not to scratch.

POWER SUPPLY CORD REPLACEMENT (for Australia Model)

Removal

1. CARRY OUT 3D CHECKS.

2. Disconnect the brown wire of the power supply cord from

the fuse holder.

3. Remove the connector CE-230 by cutting the connected wire leads to it.

Shaft

Table

Center of bracket

Page 25

R-4A56

4. Remove the single (1) screw holding the green/yellow wire of the power supply cord to the oven cavity.

5. Remove the single (1) screw holding the cord anchorage to the oven cavity.

6. Remove the power supply cord from the oven.

Re-install

1. Insert the power supply cord into the cord anchorages.

2. Connect the brown wire of the power supply cord to the fuse holder.

3. Install the green/yellow wire of the power supply cord to the oven cavity with the single (1) screw tightly.

4. Make sure that the blue wire and the white wire are stripped for 15mm length.

5. Wind the conductors of Blue and White wires each other.

6. Insert the stripped wire leads into the connector CE-230.

15 mm

Connector CE-230

Blue wire lead of  power supply cord

Wire lead of the  main wire harness

7. Clamp the connector CE-230 with the correct tool tightly.

Cord anchorage

Main harness

Brown wire

White wire

Green/yelow wire

Blue wire

Power supply cord

Connector CE230

Figure C-4. Power Supply Cord Replacement

1. CARRY OUT 3D CHECKS.

2. Remove the air duct from the oven cavity.

3. Disconnect the main wire harness and switch harness from the control panel.

4. Disconnect the leads from all switches.

5. Remove the two (2) screws holding the latch hook to the oven cavity.

6. Remove the latch hook.

7. Push the retaining tab slightly and remove the switch.

UPPER LATCH SWITCH, LOWER LATCH SWITCH, STOP SWITCH AND MONITOR SWITCH REMOVAL

Tab

Lower latch switch

Tab

Stop switch

Upper latch switch

Monitor switch

Figure C-6. Switches

5. CARRY OUT 4R CHECKS. Note: Step 5 above is important, and it must be done after

replacing power supply cord.

Power supply cord

Cord anchorage

Screw

Blue wire

Cord connector

Noise filter

Main wire harness

Brown wire

Green / Yellow wire

Earth angle

Figure C-5. Power Supply Cord Replacement

Removal

1. CARRY OUT 3D CHECKS.

2. Loosen the two (2) screws holding the brown and blue wires of the power supply cord to the cord connector on the noise filter.

3. Loosen the single (1) screw holding the earth angle and earth wire of power supply cord.

4. Remove the single (1) screw holding the cord anchorages to the oven cavity.

5. Remove the power supply cord.

Re-install

1. Insert the power supply cord into the cord anchorages.

2. Insert the brown and blue wires of power supply cord into the terminals of cord connector, referring to pictorial diagram. And tighten the screws.

3. Insert the earth wire of power supply cord into the earth angle, and tighten the screw holding the earth angle.

4. Tighten the single (1) screw holding the cord anchorages.

POWER SUPPLY CORD REPLACEMENT (for New Zealand Model)

Page 26

R-4A56

UPPER LATCH SWITCH, LOWER LATCH SWITCH, STOP SWITCH AND MONITOR SWITCH ADJUSTMENT

If the lower latch switch, stop switch, upper latch switch and monitor switch do not operate properly due to a misadjustment, the following adjustment should be made.

1. CARRY OUT 3D CHECKS.

2. Loosen the two (2) screws holding the latch hook to the oven cavity front flange.

3. With door closed, adjust the latch hook by moving it back and forward, or up and down. In and out play of the door allowed by the latch hook should be less than 0.5 mm. The horizontal position of the latch hook should be placed where the stop switch and monitor switch have activated with the door closed. The vertical position of the latch hook should be placed where the lower latch switch and upper latch switch have activated with the door closed.

4. Secure the screws with washers firmly.

5. Make sure of the upper latch switch, stop switch, lower latch switch and monitor switch operation. If those switches have not activated with the door closed, two (2) screws holding latch hook to oven cavity front flange and adjust the latch hook position.

After adjustment, make sure of following:

1. In and out play of door remains less than 0.5 mm when latched position. First check latch hook position, pushing and pulling the door toward the oven face. The results (plays of the door) should be less than 0.5mm.

2. The upper latch switch and lower latch switch interrupt the circuit before the door can be opened.

3. The monitor switch contacts close when the door is opened.

4. The stop switch contacts open when the door is opened.

5. Reinstall outer case and check for microwave leakage around the door with an approved microwave survey meter. (Refer to Microwave Measurement Procedure.)

MONITOR SWITCH

UPPER LATCH SWITCH

STOP SWITCH

LOWER LATCH SWITCH

LATCH LEVER PLUNGER

SWICTH

LATCH HEAD

DOOR OPEN BUTTON

LATCH HEAD

LATCH HOOK

DOOR

Figure C-7 Latch Switches Adjustment

DOOR REPLACEMENT AND ADJUSTMENT

1. Adjust door latch heads at a position where they smoothly catch the latch hook through the latch holes. Refer to latch switch adjustments.

2. Deviation of the door alignment from horizontal line of cavity face. The plate is to be less than 1.0mm.

3. The door is positioned with its face depressed toward the cavity face plate.

4. Reinstall outer case and check for microwave leakage around the door with an approved microwave survey meter. (Refer to Microwave Measure ment Procedure.)

LATCH HEADS

LOWER OVEN HINGE

DOOR ASSEMBLY

UPPER OVEN HINGE

OUTER CASE CABINET

RE-INSTALL

Figure C-8. Door Assembly Replacement and Adjustment

DOOR REPLACEMENT

1. CARRY OUT 3D CHECKS.

2. Remove two (2) screws holding the lower oven hinge to the oven cavity. The lower oven hinge is now free.

3. Release the door assembly from the upper oven hinge.

4. Remove door assembly.

5. Door assembly is now free.

6. Re-install upper oven hinge to the new door assembly.

7. On re-installing new door assembly, secure the lower oven hinges with the two (2) mounting screws to the oven cavity. Make sure the door is parallel with bottom line of the oven face plate and the latch heads pass through the latch holes correctly.

8. CARRY OUT 4R CHECKS.

Note: After any service to the door, an approved microwave

survey meter should be used to assure compliance with proper microwave radiation standards. (Refer to Microwave Measurement Procedure.)

DOOR ADJUSTMENT

When removing and/or loosening hinges such as in door

replacement, the following adjustment criteria are taken. Door is adjusted to meet the following three conditions by keeping screws of hinge loose.

Page 27

R-4A56

CHOKE COVER REMOVAL

1. Insert an iron plate (thickness of about 0.5mm) or flat type screw driver to the gap between the choke cover and door panel as shown in the figure to free the engaging part.

2. Lift up the choke cover, now cover is free.

FLAT TYPE SCREW-DRIVER

PROTECT BY TAPE

FLAT TYPE SCREW-DRIVER

CHOKE COVER

DOOR PANEL

DOOR PARTS REMOVAL

Remove the door assembly, referring to from item 1 through item 5 of “DOOR REPLACEMENT”.

1. Place the door assembly on a soft cloth with latch heads facing up.

2. Remove the choke cover, referring to “CHOKE COVER REMOVAL”.

LATCH HEAD REMOVAL

3. Lift up the latch head towards the direction that the arrow shows in the figure C-9, and release the latch head from the holes in the door panel.

4. Release the latch spring with the latch head from the tabs of the door panel.

5. Release the latch spring from the latch head.

6. Now, the latch head is free.

LATCH HEAD RE-INSTALL

1. Pick up the latch spring and catch the one ring of the latch spring on the tab of the door panel as shown in Figure C-

2. Catch the other ring of the latch spring on the tab of the latch head.

3. Install the latch head to the holes in the door panel.

Tab of the latch head

Ring

Latch spring

Ring

Tab of the door panel

Door Panel

Latch head

Figure C-9. Latch head removal and re-install

DOOR FRAME REMOVAL

Remove the door assembly, refer to “DOOR REPLACEMENT”

1. Place the door assembly on a soft cloth with facing up.

2. Tear the door screen from the door frame.

3. Remove the two (2) screws holding the door frame to the door panel assembly.

4. Release the nine (9) tabs of the door frame from the door panel.

5. Release the door frame from the door assembly, now the door frame is free.

Note: We recommend to replace the door assembly when

the door frame or the door panel is replaced. Because it is little difficult to remove the door frame from the door panel.

SEALER FILM

Removal

1. Tear the sealer film from the door panel.

2. Now, the sealer film is free.

Installation

1. Put the adhesive tape on the backing film of the sealer film.

2. Tear the backing film by pulling the adhesive tape.

3. Put the pasted side of the sealer film on the door panel.

Sealer film

Backing film

Adhesive tape

Sealer Film

Page 28

R-4A56

MICROWAVE MEASUREMENT

After adjustment of door latch switches, monitor switch and door are completed individually or collectively, the following leakage test must be performed with a survey instrument and it must be confirmed that the result meets the requirements of the performance standard for microwave oven.

REQUIREMENT

The safety switch must prevent microwave radiation emission in excess of 5mW/cm2 at any point 5cm or more from external surface of the oven.

PREPARATION FOR TESTING:

Before beginning the actual test for leakage, proceed as follows;

1. Make sure that the test instrument is operating normally as specified in its instruction booklet. Important: Survey instruments that comply with the requirement for instrumentations as prescribed by the performance

standard for microwave ovens must be used for testing. Recommended instruments are: NARDA 8100 NARDA 8200 HOLADAY HI 1500 SIMPSON 380M

2. Place the oven tray into the oven cavity.

3. Place the load of 275 ± 15ml of water initially at 20 ± 5˚C in the centre of the oven tray. The water container should be a low form of 600 ml beaker with inside diameter of approx. 8.5cm and made of an electrically non-conductive material such as glass or plastic. The placing of this standard load in the oven is important not only to protect the oven, but also to insure that any leakage is measured accurately.

4. Close the door and turn the oven ON with the timer set for several minutes. If the water begins to boil before the survey is completed, replace it with 275ml of cool water.

5. Move the probe slowly (not faster that 2.5cm/sec.) along the gap.

6. The microwave radiation emission should be measured at any point of 5cm or more from the external surface of the oven.

mW cm

Microwave leakage measurement at 5 cm distance

SHARP

Page 29

R-4A56

SCHEMATIC

NOTE: CONDITION OF OVEN

1.DOOR CLOSED

2.CLOCK APPEARS ON DISPLAY

Figure O-1. Oven Schematic-OFF Condition (for Australia)

Figure O-1. Oven Schematic-OFF Condition (for New Zealand)

POWER TRANSFORMER

MAGNETRON

H.V. RECTIFIER

ASYMMETRIC

RECTIFIER

CAPACITOR

1.13µF

AC2100V

TURNTABLE MOTOR

FAN MOTOR

OVEN LAMP

STOP

SWITCH

MONITOR SWITCH

CONTROL

UNIT

THERMAL

CUT-OUT



UPPER

LATCH

SWITCH

EARTH

BLU

BRN

240V~50Hz

TTM

N.O.

RY-1

G-Y

COM.

FUSE

M8A

TEMP.

FUSE

RY-2

LOWER

LATCH

SWITCH

MONITOR

RESISTOR

0.8/20W

LIVE

NEUTRAL

BLU/18 BRN/18

G-Y/18

EARTH

/AC250V

FUSE

M8A

NOISE SUPPRESSION COIL

N L

0.0022µ/250V

THERMAL

CUT-OUT

LATCH

SWITCH

LATCH

SWITCH

STOP

SWITCH

OVEN LAMP

FAN MOTOR

TURNTABLE MOTOR

POWER

TRANSFORMER

MAGNETRON

ASYMMETRIC

RECTIFIER

CAPACITOR

AC2100V

230-240V~50Hz

1.13

0.0022µ/250V

TEMP.

FUSE

A1 B2

A3 A5

COM.

RY1

RY2

CONTROL

UNIT

MONITOR SWITCH

MONITOR

RESISTOR

0.8/20W

H.V. RECTIFIER

TTM

N.O.

LOWER

0.068µ

UPPER

Page 30

R-4A56

SCHEMATIC

NOTE: CONDITION OF OVEN

1. DOOR CLOSED

2. COOKING TIME PROGRAMMED

3. START KEY TOUCHED

Figure O-2. Oven Schematic-Cooking Condition (for Australia)

Figure O-2. Oven Schematic-Cooking Condition (for New Zealand)

BLU/18 BRN/18

G-Y/18

EARTH

/AC250V

FUSE

M8A

NOISE SUPPRESSION COIL

N L

0.0022µ/250V

THERMAL

CUT-OUT

LATCH

SWITCH

LATCH

SWITCH

STOP

SWITCH

OVEN LAMP

FAN MOTOR

TURNTABLE MOTOR

POWER

TRANSFORMER

MAGNETRON

ASYMMETRIC

RECTIFIER

CAPACITOR

AC2100V

230-240V~50Hz

1.13

0.0022µ/250V

TEMP.

FUSE

A1 B2

A3 A5

COM.

RY1

RY2

CONTROL

UNIT

MONITOR SWITCH

MONITOR

RESISTOR

0.8/20W

H.V. RECTIFIER

TTM

N.O.

0.068µ

LOWER

UPPER

POWER TRANSFORMER

MAGNETRON

H.V. RECTIFIER

ASYMMETRIC

RECTIFIER

CAPACITOR

1.13µF

AC2100V

TURNTABLE MOTOR

FAN MOTOR

OVEN LAMP

STOP

SWITCH

MONITOR SWITCH

CONTROL

UNIT

THERMAL

CUT-OUT



UPPER

LATCH

SWITCH

EARTH

BLU

BRN

240V~50Hz

TTM

N.O.

RY-1

G-Y

COM.

FUSE

M8A

TEMP.

FUSE

RY-2

LOWER

LATCH

SWITCH

MONITOR

RESISTOR

0.8/20W

LIVE

NEUTRAL

Page 31

R-4A56

Figure S-1. Pictorial Diagram (for Australia)

ORG

WHT

RED

ORG

BLU

WHT

HIGH VOLTAGE COMPONENTS

MG: MAGNETRON

TRANSFORMER

T: POWER

TEMP. FUSE

150

UPPER LATCH

SWITCH

STOP SWITCH

LOWER LATCH

SWITCH

TURNTABLE

MOTOR

COM.

MONITOR

RESISTOR

WHT

BLU

WHT

TTM:

SW2:

SW4:

SW1:

TF1:

°C(MG)

OVEN LAMP

OL:

RED

WHT

RED

WHT

RED

WHT

REDRED

MONITOR

SWITCH

COM.

SW3:

WHT

RED

54321

GRN

RED

BRN

ORG

WHT

RED

CONTROL PANEL

CN-B

RY2

COM.

CN-A

135

CN-B

RY2

CN-A

RY2

COM.

THERMAL

CUT-OUT

TC:

145°C(OVEN)

FAN MOTOR

FM:

HIGH VOLTAGE WIRE A

HIGH VOLTAGE

CAPACITOR

ASYMMETRIC

RECTIFIER

H.V.RECTIFIER

NOTE: The marked " "

connector is the

positive lock

connector.

POWER SUPPLY

CORD

WHT

CONNECTOR

CE-230

EARTH

NEUTRAL

WHT

W

H

RED

CONNECTOR

CE-230

B

L

B

R

LIVE

FUSE M8A

Page 32

R-4A56

Figure S-1. Pictorial Diagram (for New Zealand)

ORG

WHT

RED

ORG

BLU

WHT

HIGH VOLTAGE COMPONENTS

MG: MAGNETRON

TRANSFORMER

T: POWER

TEMP. FUSE

150

UPPER LATCH

SWITCH

STOP SWITCH

LOWER LATCH

SWITCH

TURNTABLE

MOTOR

COM.

MONITOR

RESISTOR

WHT

BLU

WHT

TTM:

SW2:

SW4:

SW1:

TF1:

°C(MG)

OVEN LAMPOL:

RED

WHT

RED

WHT

RED

WHT

REDRED

MONITOR

SWITCH

COM.

SW3:

WHT

RED

54321

GRN

RED

BRN

ORG

WHT

RED

CONTROL PANEL

CN-B

RY2

COM.

CN-A

135

CN-B

RY2

CN-A

RY2

COM.

THERMAL

CUT-OUT

TC:

145°C(OVEN)

FAN MOTORFM:

HIGH VOLTAGE WIRE A

HIGH VOLTAGE

CAPACITOR

ASYMMETRIC

RECTIFIER

H.V.RECTIFIER

NOTE: The marked " "

connector is the

positive lock

connector.

POWER SUPPLY

CORD

WHT

CONNECTOR

CE-230

EARTH

NEUTRAL

WHT

LIVE

231

NOISE

FILTER

RED WHT

Page 33

R-4A56

Figure S-2. Contrl Panel Circuit

AC240V

50Hz

TURNTABLE

MOTOR

FAN MOTOR

OVEN LAMP

POWER

TRANSFORMER

A-3

A-5

A-1

COM

N.O

B-1 B-2

VRS1

RY1

RY2

D31

D32

C1 0.1µF/50V



D1~D4:11ES1

C2 470µF/35V



R1

4.3K

1/2W

R2

1K 1/2W

R3

1.2K 1/2W

C3 3.3µF/50V



C12 0.01µF/50V



R21

3.3K

C4 47µF/16V



ZD2

HZ

5C2

SP20



R4

470

ZD3

HZ

5A2

C5 

10µF/16V



R20 1K

D20

C30

0.1µF/50V

R31

470

Q10

DTA143ES

R10

15K

C11

C10 0.01µF/50V



Q30

DTA114ES

Q31

DTD143ES

C31

4.7µF/35V

Q1

DTC143ES

R5

15K

VC:-5V

abcdefghijk

2526 23 22 212019 18 17 16 15 14 13 12

12456789

(J6)

101520

4030 3525

IC-1 IZA430DR

RESET

AN0

AN1

AN2

AN3

AVSS

TEST

OSC1

OSC2

VCC

GND

INT1

Vdisp

TG1

D11

D10

R100 1M

CF100 CST4.00MGW

C80 330pF x 4 R80 100K x 4

R67

D41 D40

R40

100

C40

R30

15K

Q32

DTD143ES

R41

5.1K

DOOR SENSING SWITCH

R69

R68

R71

R70

3.3K x 4

AVCC

(J7) (J5)

(J4)

3.3K x 8

D67

G-10

G-11

G-12

G-7

R66

D66

R65

D65

R64

D64

R63

D63

R62

D62

R61

D61

G-6 G-5 G-4 G-3 G-2

R60

D60

G-1

09876

5321

G-8

G-9

AUTO

COOK

EASY

DEFROST

LESS

Casseroles

Reheat

Beverage

/Soup

Chicken

Pieces

POWER

LEVEL

Rice

&

Pasta

AUTO

START

CLOCK

INSTANT

COOK

START

Reheat

Pie/

Pastries

Fish

Fillets

STOP

CLEAR

Frozen

Dinner

Bacon

KEY UNIT

(J1)

ZD1

HZ

6A3

VF2 (VF1 to VF2 3Vac)

VF1

CONTROL UNIT

FLUORESCENT DISPLAY TUBE

NOTE: IF NOT SPECIFIED, 1/4W±5%

IF NOT SPECIFIED, 1SS270A

IF NOT SPECIFIED, 0.01µF/16V

Figure S - 2 . Control Panel Circuit

VP:-29V

AUTO

REHEAT

DEFROST

COOK

LOW M•LOW MED M•HIGH HIGH

Page 34

R-4A56

Figure S-3. Printed Wiring Board

R60 R61 R62 R63 R64 R65 R66 R67

D60 D61 D62 D63 D64 D65 D66 D67

R68 R69 R70 R71

R10

R80

R68

(R90) (R91)

1 2 3 4

5

CF100

R100

R5 (C9)

R4

C5

ZD3

B

C6

E

Q1

7

(J12 R12)

16

R30

C7

C4

(J7)

(J5)

(J4) (J6)

–

+

E C

(J10)

(R51)

C50)

(R52)

(R50)

ZD2

R41

VC

–

+

(C31)

SP20

D20

R20

R21

CN–G

1 12

1 5 10 15 21

42 35 30 25 22

B (Q50)

8

VP

R2

ZD1

C11

B

Q10

C10

VF1

R1

(C8)

E

C1

–

C2

+

– 

(J2)

(J3)

+

C3

Q30

B

+

E

–

+

C30

R31

BC

12

E

BC

(Q33)

9 R3 10

GND

+

–

R40

C40

E

(J11)

Q32

D40

(J33 R33)

13

VF2

TEMP.

DOOR

SW.

D41

4 3 2 1

(D33)

(J34 R34)

RED BLK

(TAB4) (TAB3)

14

D2

D1

D4

15

D3

B C E

Q31

(J32 R32)

(VRS2)

(RY3

RY2

S2

S1

P

6 5 4 3

2 1

US:BLK,CD:WHT

GE:RED,AS:ORG

US:RED,CD:GRY GE:BLK,AS:BRN

D32

(TAB1) (COM.)

(TAB2)

(H.V.)

(J1)

17

VRS1

T1

D31

C12

(H.V.)

POWER

O.L.,F.M.,T.T.M.,

CN–A

RY1

5 731

26

6

IC 1

CN–B

C31

–

DIPPING

F

,

Page 35

R-4A56

PARTS LIST

Note: The parts marked "∆" may cause undue microwave exposure.

The parts marked "*" are used in voltage more than 250V.

REF. NO. PART NO. DESCRIPTION Q'TY CODE

* *

∆

ELECTRICAL PARTS

1- 1 QFS-TA014WRE0 Temp. fuse 150˚C (MG) 1 AG 1- 2 FPWBFA221WRK0 Noise filter (for New Zealand) 1 AX 1- 3 QSW-MA111WRE0 Monitor switch (V-16G-2C25(R)) 1 AK 1- 4 QSW-MA110WRE0 Upper latch switch (V-16G-3C25(R)) 1 AK 1- 5 RTHM-A075WRE0 Thermal cut-out 145˚C (OVEN) 1 AN 1- 6 QACCAA038WRE0 Power supply cord (for Australia) 1 AX 1- 6 QACCAA039WRE0 Power supply cord (for New Zealand) 1 AX 1- 7 FH-DZA063WRK0 H.V. rectifier assembly 1 AX 1- 8 RC-QZA075WRE0 High Voltage capacitor 1 AU 1- 9 QSOCLA011WRE0 Oven lamp socket 1 AH 1-10 RLMPTA029WRE0 Oven lamp 1 AL 1-11 QFS-CA010WRE0 Fuse M8A 1 AE 1-12 RMOTEA303WRE0 Fan motor 1 AX 1-13 RTRN-A430WRE0 Power transformer 1 BQ 1-14 RV-MZA089WRE0 Magnetron 1 BF 1-15 RMOTDA133WRE0 Turntable motor 1 BE 1-16 RR-WZA003WRE0 Monitor resistor 0.8 ohm 20W 1 AG 1-17 QSW-MA110WRE0 Lower latch switch (V-16G-3C25(R)) 1 AK 1-18 QSW-MA110WRE0 Stop switch (V-16G-3C25(R)) 1 AK 1-19 QFSHDA002WRE0 Fuse holder 1 AF

CABINET PARTS

2- 1 FHNG-A172WRT0 Lower oven hinge 1 AM 2- 2 GCABUA415WRP0 Outer case cabinet (until Serial No. 9409xxxxx) 1 BE 2- 2 GCABUA310WRP0 Outer case cabinet (until Serial No. 9410xxxxx) 1 BF 2- 3 MHNG-A280WRT0 Upper oven hinge 1 AM 2- 4 PCOVPA249WRP0 Turntable motor cover 1 AK 2- 5 PCAPHA015WRE0 Cabinet cap 2 AD 2- 6 GLEGPA023WRE0 Foot 4 AC

CONTROL PANEL PARTS

3- 1 CPWBFA498WRK0 Control unit (New zealand only) 1 BF 3- 1A QCNCMA234DRE0 3-pin connector(A) 1 AC 3- 1B QCNCMA275DRE0 2-pin connector(B) 1 AB 3- 1C QCNCWA030DRE0 12-pin connector(G) 1 AF 3- 1D RV-KXA037DRE0 Fluorescent display tube 1 AU C1 RC-KZA087DRE0 Capacitor 0.1µF 50V 1 AB C2 VCEAB31VW477M Capacitor 470µF 35V 1 AC C3 VCEAB31HW335M Capacitor 3.3µF 50V 1 AA C4 VCEAB31CW476M Capacitor 47µF 16V 1 AA C5 VCEAB31CW106M Capacitor 10µF 16V 1 AA C6-7 VCKYD11CY103N Capacitor 0.01µF 16V 2 AH C10 VCTYF31HF103Z Capacitor 0.01µF 50V 1 AB C11 VCKYD11CY103N Capacitor 0.01µF 16V 1 AH C12 VCTYF31HF103Z Capacitor 0.01µF 50V 1 AB C30 VCEAB31HW104M Capacitor 0.1µF 50V 1 AM C31 VCEAB31VW475M Capacitor 4.7µF 35V 1 AA C40 VCKYD11CY103N Capacitor 0.01µF 16V 1 AH C80 RMPTEA009DRE0 Capacitor array B5RCO122-33N (330pF x 4) 1 AE CF100 RCRS-A012DRE0 Ceramic resonator (CST4.00MGW) 1 AD D1-4 VHD11ES1///-1 Diode (11ES1) 4 AB D20 VHD1SS270A/-1 Diode (1SS270A) 1 AA D31-32 VHD1SS270A/-1 Diode (1SS270A) 2 AA D40-41 VHD1SS270A/-1 Diode (1SS270A) 2 AA D60-67 VHD1SS270A/-1 Diode (1SS270A) 8 AA IC1 RH-IZA430DRE0 LSI 1 AR Q1 VSDTC143ES/-3 Transistor (DTC143ES) 1 AB Q10 VSDTA143ES/-3 Transistor (DTA143ES) 1 AB Q30 VSDTA114ES/-3 Transistor (DTA114ES) 1 AB Q31-32 VSDTD143ES/-3 Transistor (DTD143ES) 2 AC R1 VRD-B12HF432J Resistor 4.3k ohm 1/2W 1 AH R2 VRD-B12HF102J Resistor 1.0k ohm 1/2W 1 AA R3 VRD-B12HF122J Resistor 1.2k ohm 1/2W 1 AA R4 VRD-B12EF471J Resistor 470 ohm 1/4W 1 AA R5 VRD-B12EF153J Resistor 15k ohm 1/4W 1 AA R10 VRD-B12EF153J Resistor 15k ohm 1/4W 1 AA R20 VRD-B12EF102J Resistor 1.0k ohm 1/4W 1 AA R21 VRD-B12EF332J Resistor 3.3k ohm 1/4W 1 AA R30 VRD-B12EF153J Resistor 15k ohm 1/4W 1 AA

Page 36

R-4A56

Note: The parts marked "∆" may cause undue microwave exposure.

The parts marked "*" are used in voltage more than 250V.

REF. NO. PART NO. DESCRIPTION Q'TY CODE

∆

∆ ∆

∆

R31 VRD-B12EF471J Resistor 470 ohm 1/4W 1 AA R40 VRD-B12EF101J Resistor 100 ohm 1/4W 1 AA R41 VRD-B12EF512J Resistor 5.1k ohm 1/4W 1 AA R60-71 VRD-B12EF332J Resistor 3.3k ohm 1/4W 12 AA R80 RR-DZA089DRE0 Resistor array (RGLD4X104J) 1 AB R100 VRD-B12EF105J Resistor 1M ohm 1/4W 1 AA RY1 RRLY-A080DRE0 Relay (OJ-SH-124LM) 1 AG RY2 RRLY-A076DRE0 Relay (OMIF-S-124LM) 1 AK SP20 RALM-A014DRE0 Buzzer (PKM22EPT-CA) 1 AG T1 RTRNPA064DRE0 Transformer 1 AS VRS1 RH-VZA010DRE0 Varistor (TNR15G471K) 1 AE ZD1 VHEHZ6A3///-1 Zener diode (HZ6A-3) 1 AC ZD2 VHEHZ5C2///-1 Zener diode (HZ5C-2) 1 AA ZD3 VHEHZ5A2///-1 Zener diode (HZ5A-2) 1 AA 3- 2 FPNLCB101WRK0 Control panel frame with key unit 1 BA 3- 2-1 FUNTKA611WRE0 Key unit 1 AY 3- 3 JBTN-A817WRF0 Open button 1 AK 3- 4 MSPRCA050WRE0 Open button spring 1 AB 3- 5 XEPSD30P10XS0 Screw : Control unit mounting 3 AA

OVEN PARTS

4- 1 LBNDKA038WRP0 Capacitor holder 1 AH 4- 2 LSTPPA069WRF0 Cord anchorage (upper) 1 AE 4- 3 LSTPPA070WRF0 Cord anchorage (lower) 1 AD 4- 4 FDAI-A150WRY0 Bottom plate 1 AY 4- 5 PDUC-A406WRF0 Air duct 1 AK 4- 6 PHOK-A076WRF0 Latch hook 1 AQ 4- 7 PCUSUA237WRP0 Waterproof cushion 1 AF 4- 8 PCUSUA236WRP0 Partition cushion 1 AF 4- 9 FOVN-A210WRT0 Oven cavity 1 BK 4-10 PCUSUA368WRP0 Cushion 1 AK 4-11 MLEVPA166WRF0 Latch lever 1 AE 4-12 FROLPA047WRK0 Roller stay 1 AW 4-13 NTNT-A036WRE0 Turntable 1 AX 4-14 GFTA-A008WRW0 Oven lamp access cover 1 AF 4-15 NCPL-A015WRF0 Turntable coupling 1 AD 4-16 PSPA-A084WRE0 Foot washer 1 AB 4-17 PCOVPA212WRE0 Waveguide cover 1 AF 4-18 PCUSUA157WRP0 Cushion 1 AC 4-19 PCUSUA300WRP0 Cushion 1 AH 4-20 PPACGA096WRE0 O-ring 1 AG 4-21 PFILWA041WRE0 Oven lamp filter 1 AA 4-23 PGIDHA044WRP0 Magnetron air guide 1 AM 4-24 LANGQA167WRM0 Earth angle (for New Zealand) 1 AB 4-25 LANGQA288WRP0 Noise filter angle (for New Zealand) 1 AC 4-26 PCUSGA322WRP0 Cushion 2 AF 4-27 PCUSGA321WRP0 Cushion 1 AH 4-28 PCUSUA278WRP0 MG cushion 1 AF 4-29 PCUSGA339WRP0 Trans. cushion 2 AG 4-30 NFANJA020WRE0 Fan blade 1 AG 4-31 PDUC-A468WRF0 Fan duct 1 AR

DOOR PARTS

5 CDORFA664WRK0 Door assembly, complete. 1 BG 5- 1 FDORFA229WRT0 Door panel 1 BG 5- 2 GCOVHA228WRF0 Choke cover 1 AH 5- 3 LSTPPA090WRF0 Latch head 1 AF 5- 4 MSPRTA114WRE0 Spring 1 AD 5- 5 HPNL-A515WRE0 Door screen 1 AX 5- 6 PSHEPA336WRP0 Sealer film 1 AF 5- 7 GWAKPA238WRF0 Door frame 1 AX

MISCELLANEOUS

6- 1 TCADCA543WRR0 Cook book 1 AZ 6- 2 TINS-A456WRR0 Instruction book 1 AK 6- 3 TCAUHA185WRR0 Microwave caution (for New Zealand) 1 AG 6- 4 PTUBUA004WRE0 Tube 220 1 AK 6- 5 QW-QZA141WRE0 High voltage wire A 1 AH 6- 6 TCAUHA055WRR0 Caution label 1 AF 6- 7 PTUBUA003WRE0 Tube 110 1 AF 6- 8 FW-VZB137WRE0 Main wire harness (for Australia) 1 AY 6- 8 FW-VZB138WRE0 Main wire harness (for New Zealand) 1 AY

Page 37

R-4A56

Note: The parts marked "∆" may cause undue microwave exposure.

The parts marked "*" are used in voltage more than 250V.

REF. NO. PART NO. DESCRIPTION Q'TY CODE

HOW TO ORDER REPLACEMENT PARTS

To have your order filled prompty and correctly, please furnish the following information.

1. MODEL NUMBER 2. REF. NO.

3. PART NO. 4. DESCRIPTION

6- 9 FW-VZB139WRE0 Low voltage harness 1 AM 6-10 TSPCNC034WRR0 Rating label (for Australia) 1 AD 6-10 TSPCNC036WRR0 Rating label (for New Zealand) 1 AC 6-11 TGAN-A079WRR0 Guarantee card (for New Zealand) 1 AF 6-12 LBNDKA049WRE0 Wire tight 1 AB 6-13 LHLDWA010WRE0 Purse lock S (for Australia) 1 AC 6-14 QTANP0020YBE0 Connector CE 230 (for Australia) 1 AA 6-15 TLABSA029WRR0 Fuse label (for Australia) 1 AC

SCREWS, NUTS AND WASHERS

7- 1 XFPSD30P10000 Screw; M3 x 10 zinc plated steel (for Australia) 1 AB 7- 2 XOTSD40P12RV0 Screw; M4 x 12 9 AB 7- 3 XOTSD40P12000 Screw; M4 x 12 7 AA 7- 5 XFTSD40P30000 Screw; M4 x 30 zinc plated steel 1 AA 7- 6 LX-CZ0052WRE0 Special screw; 2 AA 7- 7 LX-EZA036WRE0 Special screw 2 AA 7- 8 XOTSE40P08000 Screw; M4 x 8 4 AB 7- 9 XFPSD30P06000 Screw; M3 x 6 zinc plated steel 1 AA 7-10 XFPSD40P08K00 Screw; M4 x 8 zinc plated steel (for Australia) 2 AA 7-10 XFPSD40P08K00 Screw; M4 x 8 zinc plated steel (for New Zealand) 3 AA 7-11 XFPSD40P08000 Screw; M4 x 8 zinc plated steel 6 AA 7-12 XHTSD40P08RV0 Screw; M4 x 8 zinc plated steel (for Australia) 5 AA 7-12 XHTSD40P08RV0 Screw; M4 x 8 zinc plated steel (for New Zealand) 6 AA 7-13 LX-WZA004WRE0 Washer; 1 AA 7-14 XBTSD40P08RV0 Screw; M4 x 8 1 AA 7-18 XWHNZ40-05080 Washer; 1 AA 7-20 XBTUW40P08000 Screw; M4 x 8 1 AA 7-21 XCPSD30P08X00 Screw; M3 x 8 2 AA 7-22 XBPSD40P25000 Screw; M4 x 25 2 AA 7-23 XNESD40-32000 Nut; 2 AA 7-24 XWVSD40-05000 Washer; 1 AA 7-25 XFTSD40P10000 Screw; M4 x 10 1 AA

Page 38

R-4A56

OVEN AND CABINET PARTS

6-3

7-24

4-17

7-20

4-15

4-21

7-3

7-25

7-13

4-20

1-15

7-11

4-11

7-18

7-3

7-2

2-1

2-4

7-12

7-3

2-6

7-2

4-18

1-9

6-9

7-10

1-16

1-13

7-7

4-10

4-6

1-17

1-18

1-4

1-3

4-5

4-2

1-10

7-22

1-12

4-31

7-23

4-30

1-7

7-12

4-23

1-8

4-1

1-14

4-28

7-8

4-13

4-12

2-3

7-2

x 2

4-19

6-6

1-5

4-7

1-1

7-9

7-8

2-5

7-3

4-9

7-5

1-6

4-3

4-14

7-12

7-14

7-11

7-6

7-12

4-29

2-2

4-8

7-10

4-24

7-10

4-25

1-2

1-11

7-12

7-3

4-26

4-27

7-2

2-5

for New 

Zealand

1-11

7-1

1-19

for 

Australia

4-4

4-16

6-15

Page 39

R-4A56

CONTROL PANEL PARTS

DOOR PARTS

3-2

3-2-1

3-3

3-4

3-1

3-5

6-10

5-4

5-3

5-2

5-1

5-6

5-5

7-21

5-7

Page 40

R-4A56

'94SHARP CORP. (07K0.820E) Printed in Australia

MISCELLANEOUS

110 mm

220 mm

6-5

6-9

Actual wire harness may be different than illustration.

6-8

240 mm

6-12

6-4

6-7

6-14

6-13

PACKING AND ACCESSORIES

TRAY HOLDER *(SPADFA208WRE0)

TURNTABLE TRAY

INSTRUCTION BOOK

COOK BOOK

ROLLER STAY

TRAY PAD *(SPADFA207WRE0)

DOOR PROTECTOR *(SPADPA178WRE0)

DOOR PAD *(SPADFA061WRE0)

CABINET COVER (R-4X55B) *(SPAKHA003WRE0)

TOP PAD *(SPADBA524WRE0)

PLASTIC BAG *(SSAKHA032WRE0)

PACKING ADD KIT *(CPADBA113WRK0)

PACKING CASE SPAKCC388WRE0 (Australia)

SPAKCC390WRE0 (New Zealand)

* Not replacement Items.