Sharp R-3C57 Service Manual

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R-3C57

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-3C57

S7501R3C57PJZ

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 .......................................................................................................................................................... 7

TEST PROCEDURE ............................................................................................................................................ 9

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-3C57

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R-3C57

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

R3C57

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-3C57

PRODUCT SPECIFICATIONS

ITEM DESCRIPTION

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

50 Hertz

Single phase, 3 wire earthed Power Consumption 1.37kW Power Output 900 watts nominal of RF microwave energy (IEC 705)

750 watts (2 litre water load)

Operating fequency 2450 MHz Case Dimensions Width 520 mm

Height 305 mm including foot

Depth 389 mm Cooking Cavity Dimensions Width 348 mm

Height 197 mm

Depth 368 mm Turntable diameter 325mm 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

INFORMATION COOK pads

HELP pad

CONVENIENCE MEALS pads

NUMBER pads

POWER LEVEL pad

MORE, LESS pads

TIMER pad

MEMORY pads

CLOCK pad

AUTO START pad

STOP/CLEAR pad

INSTANT COOK/START pad Set Weight Approx. 15 kg

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

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R-3C57

APPEARANCE VIEW

3

11144

1. Ventilation openings

2. Oven lamp

3. Door hinges

4. Door safety latches

5. See through door

6. Door seals and sealing surfaces

7. Coupling

8. Door open button

9. Touch control panel

10.Digital readout

11.Wave guide cover

12.Power supply cord

13.Rating label

14.Menu label

TOUCH CONTROL PANEL

HELP

REHEAT

CONVENIENCE MEALS

MEAT

Pasta Meal

POWER

LEVEL

AUTO

START

STOP

CLEAR

TIMER

LESS MORE

CLOCK

MEMORY1MEMORY

Frozen Dinner

DEFROST

RICE

PASTA

VEGETABLES

Info Display



1 2 3 4 5 6 7 8 9 O

INSTANT COOK

START

  INFORMATION COOK PADS Press to select Information Cook

mode.



     

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

TIMER PAD Press to set Timer.   

MORE ( ), LESS ( ) PADS

 Press to increase/decrease the time in one minute increments during cooking or to alter the doneness for the Convenience Meals or Information Cook modes.  

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

HELP PAD Press to select information guide on/off, child lock or demonstration modes. Press to get cooking information.  CONVENIENCE MEALS PADS Press to select Convenience Meals menu.  NUMBER PADS Press to enter cooking times, clock time, weight or quantity of food.   MEMORY PADS Press to enter two frequently used cooking programmes. Press to recall the memorized programme.       AUTO START PAD Press to set Auto Start time.

CLOCK PAD Press to set Clock  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.

COOK KG DEF HELP

Indicator

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R-3C57

OPERATION SEQUENCE

OFF CONDITION

Closing the door activates all door interlock switches (1st. latch switch, 2nd. 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 shows SHARP , MICRO- , WAVE and OVEN .

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

3. : appears in the display.

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 pad 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 channeled 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) 1st. latch switches COM-NO Closed Open 2nd. 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 1st. latch switch, 2nd. 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 1st and 2nd. latch switches.

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

of a cooking program, the 1st. latch switch, 2nd. 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. After that the contacts of the 1st. latch switch, 2nd. latch switch and stop switch are closed.

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

the1st. latch switch, 2nd. latch switch remain closed. The fuse M8A will blow, because the monitor switch is closed and a short circuit is caused.

MEDIUM HIGH, MEDIUM, MEDIUM LOW, LOW COOKING

When the microwave oven is preset for variable cooking power, 230-240 volts A.C. power is supplied to the power transformer intermittently within a 32-second time base through the relay contact which is coupled with the currentlimiting relay. 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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FUNCTION OF IMPORTANT COMPONENTS

DOOR OPEN MECHANISM

The door is opened by pushing the open button on the control panel, refer to the Figure D-1. When the open button is pushed, the open button pushes up the switch lever, and then the switch lever pushes up the the latch head. The latch heads are moved upward and released from latch hook. Now the door will open.

LATCH HEADS

LATCH HOOK

2ND. LATCH SWITCH

MONITOR  SWITCH

SWITCH LEVER

STOP SWITCH

1ST. LATCH SWITCH

Figure D-1. Door Open Mechanism

1ST. LATCH SWITCH, 2ND. 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 1st. latch switch and 2nd. latch switch 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 1ST. LATCH SWITCH, 2ND. LATCH SWITCH MONITOR SWITCH AND MONITOR RESISTOR FOR PROPER OPERATION.

MONITOR RESISTOR R 0.8Ω 20W

The monitor resistor prevents the fuse M8A bursting when the fuse M8A 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 temperature rise of the power transformer by blowing the fuse M8A when the high voltage rectifier is shorted.

D2 D1

ASYMMETRIC RECTIFIER

HIGH VOLTAGE RECTIFIER

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 M8A 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 all electrical parts are cut off.

FUSE M8A

1. The fuse M8A blows when the contacts (COM-NO) of the 1st. latch switch and 2nd. latch switch remain closed with the oven door open and when the monitor switch closes.

2. The fuse M8A also blows when asymmetric rectifier, H.V. rectifier, H.V. wire harness, H.V.capacitor, magnetron or secondary winding of power transformer is shorted.

3. If the wire harness or electrical components are shortcircuited, this fuse M8A blows to prevent an electric shock or fire hazard.

THERMAL CUT-OUT TC 145˚C (MG)

This thermal cut-out protects the magnetron against overheating. If the temperature goes up higher than 145˚C because the fan motor is interrupted, the ventilation openings are blocked, the thermal cut-out will open and the line voltages to the power transformer will be cut off and the operation of the magnetron will be stopped. The defective thermal cut-out must be replaced with new one.

THERMAL CUT-OUT TC 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

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R-3C57

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 defective thermal cut-out must be replace with new one.

THERMAL CUT-OUT 95˚C (FAN MOTOR)

The thermal cut-out protect the fan motor against overheating. If its temperature goes up higher than 95˚C because the fan motor is locked or the ventilation operating are blocked, the contacts of the thermal cut-out will open and switch off the oven. When the oven cools itself down to 75˚C, the contacts of the thermal cut-out will close again.

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

NOISE FILTER (FOR NEW ZEALAND)

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

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R-3C57

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 1st. latch switch 2nd. latch switch - monitor switch - monitor resistor circuit, check the 1st. latch switch, 2nd. latch switch, monitor switch and monitor resistor before replacing the fuse M8A.

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MAGNETRON

POWER TRANSFORMER

H.V. RECTIFIER ASSEMBLY

HIGH VOLTAGE CAPACITOR

1ST. LATCH SWITCH

2ND. LATCH SWITCH

STOP SWITCH

MONITOR SWITCH

MONITOR RESISTOR

TEMPERATURE FUSE 95˚C

THERMAL CUT-OUT 145˚C

FAN MOTOR

TURNTABLE MOTOR

FUSE M8A

TOUCH CONTROL PANEL

KEY UNIT

RELAY (RY-1, RY-2)

FOIL PATERN ON P.W.B.

POWER SUPPLY CORD

SHORTED WIRE HARNESS

OPENED WIRE HARNESS

OVEN LAMP OR SOCKET

WALL OUTLET

MISADJUSTMENT SWITCH

HOME FUSE OR BREAKER

BLOCKED COOLING FAN

BLOCKED VENTILATION

NOISE FILTER (FOR N.Z.)

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

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

Display does not show anything when 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

ABCDEEEEGFFH HI JKLM RECK CKRE CK CKCKCK CK N

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TEST PROCEDURES

PROCEDURE

LETTER

CARRY OUT 3D CHECK. 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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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) = 49 sec...................................................................... 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 for49 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 power 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. 1.4 Ω

b. Secondary winding............... approx. 98 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.

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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, O.C.; Open circuit

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

4R CHECKS.

E THERMAL CUT-OUT TEST

CARRY OUT 3D CHECKS. Disconnect the leads from the terminals of the 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 This is not resetable type Above 145˚C Closed circuit. Thermal cut-out 95˚C Below 75˚C Above 95˚C Closed circuit.

Page 15

R-3C57

PROCEDURE

LETTER

COMPONENT TEST

TEST PROCEDURES (CONT'D)

If incorrect readings are obtained, replace the thermal cut-out. An open circuit thermal cut-out 145˚C (MG) indicates that the magnetron has overheated, this may be

due to resistricted 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.

An open circuit thermal cut-out 95˚C (FAN) indicates that the fan motor winding has overheated, this may be due to blocked ventilation or locked cooling fan.

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.

G MONITOR RESISTOR TEST

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.

H MOTOR WINDING TEST

Table: Resistance of Motor Motors Resistance Fan motor Approximately 370 Ω Turntable motor Approximately 16.08 kΩ

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

I 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 2nd. 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 occured 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

J TOUCH CONTROL PANEL ASSEMBLY TEST

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.

Page 16

R-3C57

TEST PROCEDURES (CONT'D)

PROCEDURE

LETTER

COMPONENT TEST

1. Key Unit Note : Check key unit ribbon connection before replacement. 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. Before replacing the control unit, perform the Key unit test (Procedure L) to determine if control unit is faulty.

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.

K KEY UNIT TEST

If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon is marking 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, disconnecct the flat ribbon cable 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 door sensing 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 marking 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 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.

CARRY OUT 3D CHECKS. Remove the outer case and check the voltage between Pin Nos. 3 and 5 of the 3 pin connector (A) on

the control unit with an A.C. voltmeter. The meter should indicate 240 volts, if not check oven circuit.

RY1 and RY2 Relay Test These relays are operated by D.C. voltage. Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation.

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.

L RELAY TEST

G12

G11

G10

G8 G7 G6 G5 G4 G3 G2 G1

KEY UNIT

54321

09876

AUTO

START

POWER

LEVEL

RICE

PASTA

INSTANT

COOK



START

DEFROST

Frozen

Dinner

CLOCK

TIMER

MEMORY

REHEAT

MEAT

VEGE-

TABLES

Pasta

Meal

STOP

CLEAR

HELP

LESS

Page 17

R-3C57

TEST PROCEDURES (CONT'D)

PROCEDURE

LETTER

COMPONENT TEST

N 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 0.0022µF

WHT

RED

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

If incorrect readings are obtained, replace the noise filter unit. CARRY OUT 4R CHECKS.

VRS1

(J1)

(J2)

CN-A

LOT NO.

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. CARRY OUT 3D CHECKS.

STEPS OCCURANCE CAUSE OR CORRECTION

1 The rated AC voltage is not present at Check supply voltage and oven power cord.

POWER terminal of CPU connector (CN-H)

2 The rated AC voltage is present at primary Low voltage transformer or secondary circuit defective.

side 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)

NOTE: *At the time of making these repairs, make

a visual inspection of the varistor. check for burned damage and examine the transformer with a 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.

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

(PWB) IS OPEN

RELAY SYMBOL OPERATIONAL VOLTAGE CONNECTED COMPONENTS

RY1 APPROX. 25.0V D.C. Oven lamp / Turntable motor / Cooling fan motor RY2 APPROX. 29.0V D.C. Power transformer

CARRY OUT 4R CHECKS.

Page 18

R-3C57

TOUCH CONTROL PANEL ASSEMBLY

OUTLINE OF TOUCH CONTROL PANEL

The touch control section consists of the following units 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 R11, R12, R13, R20, R21 and R23. When a key pad is touched, a signal is completed through the key unit and passed back to the LSI through R00, R01, R02 and R03 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 -34V Fluorescent display tube : Grid

and anode voltage

VF1 2.2Vac Filament of fluorescent display

tube

VF2 (VF1 to VF2 voltage)

3) Synchronizing Signal Circuit

The 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 audible 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 7-digits, 15-segments are used for displaying figures.

Page 19

R-3C57

DESCRIPTION OF LSI

LSI(IZA655DR)

The I/O signal of the LSI(IZA655DR) is detailed in the following table.

Pin No. Signal I/O Description

1 Vdisp IN Anode (segment) of Fluorescent Display light-up voltage: -34V

Vp voltage of power source circuit input.

2 R00 IN Signal coming from touch key.

When either one of G12 line keys on key matrix is touched, a corresponding signal out of R11 - R13, R20, R21, R23 and D6 will be input into R00. When no key is touched, the signal is held at "L" level.

3 R01 IN Signal coming from touch key.

When either one of G11 line keys on key matrix is touched, a corresponding signal out of R11 - R13, R20, R21, R23 and D6 will be input into R01. When no key is touched, the signal is held at "L" level.

4 R02 IN Signal coming from touch key.

When either one of G10 line keys on key matrix is touched, a corresponding signal out of R11 - R13, R20, R21, R23 and D6 will be input into R02. When no key is touched, the signal is held at "L" level.

5 R03 IN Signal coming from touch key.

When either one of G9 line keys on key matrix is touched, a corresponding signal out of R11 - R13, R20, R21, R23 and D6 will be input into R03. When no key is touched,

the signal is held at "L" level. 6 TEST IN Connected to VC. 7 RESET IN Auto clear terminal.

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

set to “L” level the moment power is applied, at this time the LSI is reset. Thereafter

set at “H” level. 8 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. 9 OSC2 OUT Internal clock oscillation frequency control output.

Output to control oscillation input of OSC2. 10/11 GND/AVSS IN/IN Connected to VC. 2 AN0 IN Input signal which communicates the door open/close information to LSI.

Door closed; "H" level signal.

Door opend; "L" level signal. 13-14 AN1-AN2 IN Terminal to change cooking constant. 15 R33 OUT Oven lamp, turntable motor and cooling fan motor driving signal. (Square

Waveform : 45Hz)

To turn on and off shut-off relay. The square (45Hz) is delivered to the relay driving

circuit and cook relay control circuit. 16 P40 OUT Magnetron high-voltage circuit driving signal.

To turn on and off the cook relay. In Low operation, the signals holds “L” level during

microwave cooking and “H” level while not cooking. In other cooking modes

(P10~P90) the signal turns to “H” level and “L” level in repetition according to the

power level. 17-19 R41-R43 OUT Segment data signal.

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. 20/21 AVCC/VCC IN/IN Connected to GND. 22 INT IN Signal to synchronized with commercial source frequency(50Hz).

This is basic timing for time processing of LSI. 23-24 D1-D2 OUT Segment data signal.

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.

Page 20

R-3C57

Pin No. Signal I/O Description

25 BUZZ OUT Signal to sound buzzer.

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

26-27 D4-D5 OUT Segment data signal.

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.

28 D6 OUT Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of G8 line keys on key matrix is touched.

29-30 D7-D8 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.

31-34 R80-R83 OUT Digit selection signal.

35 R10 OUT Digit selection signal.

36 R11 OUT Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of G7 line keys on key matrix is touched.

37 R12 OUT Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of G6 line keys on key matrix is touched.

38 R13 OUT Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of G5 line keys on key matrix is touched.

39 R20 OUT Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of G4 line keys on key matrix is touched.

40 R21 OUT Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of G3 line keys on key matrix is touched.

41 R22 OUT Segment data signal.

Signal similar to P41.

42 R23 OUT Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of G1 line keys on key matrix is touched.

Page 21

R-3C57

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 supply 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

of the oven: CAUTION: THE HIGH VOLTAGE TRANSFORMER OF THE MICROWAVE OVEN IS STILL LIVE DURING SERVICING PRESENTS A HAZARD.

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; and 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

approx. 1M ohm

Transistor 2SA933S DTA143ES KRA101M KRC243M

SERVICING

two can’t be separated. For those models, check and 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 is 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) After aluminium foil is removed, be careful that abnormal voltage due to static electricity etc. is not applied to the input or output terminals.

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

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

Page 22

R-3C57

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. CARRY OUT 3D CHECKS.

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, CONTROL PANEL PARTS, DOOR PARTS’, when carrying out any of the following removal procedures:

To remove the components, procedure as follows.

1. Disconnect oven from power supply.

2. Remove four(4) screws from rear and two(2) screwsalong the right side edge of case.

OUTER CASE REMOVAL

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

4. Lift entire case from the unit.

CAUTION: DISCONNECT OVEN FROM POWER SUP-

PLY BEFORE REMOVING OUTER CASE.

POWER TRANSFORMER REMOVAL

2. Install the terminal insulator to receptacle of filament lead (longer one) of power transformer.

3. Rest transformer on the bottom plate right with its primary terminals toward the oven face plate.

4. Secure transformer with four screws to bottom plate right.

5. Re-connect wire leads (primary and high voltage) to power transformer and filament leads of transformer to magnetron and high voltage capacitor. Refer to "PICTORIAL DIAGRAM".

6. Re-install outer case and check that oven is operating properly.

1. CARRY OUT 3D CHECKS.

2. Disconnect wire leads from power transformer, magnetron and capacitor terminals.

3. Remove four (4) screws holding transformer to bottom plate right.

4. Remove transformer from bottom plate right.

5. Remove the one (1) terminal insulator and tube from filament lead (longer one) of power transformer.

Re-install

1. Insert tube into filament lead (longer one) of power transformer.

1. Open covers of the terminal insulator by using small flat type screw driver.

2. Remove the receptacle from the terminal insulator.

3. Now, the terminal insulator is free.

Installation

1. Insert the receptacle into terminal insulator.

2. Close covers of the terminal insulator, as shown illustlated below.

TERMINAL INSULATOR REPLACEMENT

RECEPTACLE

COVERS

Terminal  insulator

Flat type screw driver

Page 23

R-3C57

Removal

1. CARRY OUT 3D CHECKS.

2. Disconnect wire leads from magnetron.

3. Remove the two (2) screws holding chassis support to oven cavity front plate and magnetron.

4. Remove the chassis support from oven.

5. Carefully remove the two (2) screws holding magnetron to waveguide flange.

6. Lift up magnetron with care so that magnetron antenna is not hit by any metal object around antenna.

7. Now, the magnetron is free.

Re-install

1. Re-install the magnetron to waveguide flange with the two (2) screws diagonally as shown in Figure C-1.

2. Re-install the chassis support to oven cavity front plate and magnetron with the two (2) screws.

3. Reconnect the wire leads to the magnetron. Refer to "PICTORIAL DIAGRAM".

MAGNETRON REMOVAL

4. Re-install outer case and check that the oven is operating properly.

CAUTION: WHEN REPLACING MAGNETRON, BE SURE

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

Figure C-1. Magnetron replacement

WAVEGUIDE FLANGE

SCREWS

MAGNETRON

HIGH VOLTAGE RECTIFIER AND HIGH VOLTAGE CAPACITOR REMOVAL

6. Disconnect wire leads from capacitor and remove capacitor holder.

7. High voltage rectifier assembly and high voltage capacitor are free..

CAUTION: WHEN REPLACING HIGH VOLTAGE

RECTIFIER AND HIGH VOLTAGE CAPACITOR, GROUND SIDE TERMINAL OF THE HIGH VOLTAGE RECTIFIER MUST BE SECURED FIRMLY WITH A GROUNDING SCREW.

1. CARRY OUT 3D CHECKS.

2. Disconnect the high voltage of the high voltage rectifier assembly from the power transformer.

3. Remove one (1) screw holding capacitor holder to oven cavity rear plate.

4. Disconnect rectifier terminal from capacitor. Rectifier and high voltage assembly is now free.

5. Remove one (1) screw holding high voltage rectifier assembly to capacitor holder.

POSITIVE LOCK® CONNECTOR REMOVAL

1. CARRY OUT 3D CHECKS.

2. Pushing the lever of positive lock® connector.

3. Pull out the positive lock® connector. CAUTION: WHEN YOU (SERVICE ENGINEERS) CON-

NECT THE POSITIVE LOCK® CONNECTORS TO THE TERMINALS, CONNECT THE POSITIVE LOCK® SO THAT THE LEVER FACE YOU (SERVICE ENGINEERS).

Figure C-2. Positive lock® connector

Terminal

Push

Pull down

Lever

Positive lock

connector

adhesive on the control panel frame surfaces completely with alcohol.

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.

CONTROL PANEL ASSEMBLY REMOVAL

1. CARRY OUT 3D CHECKS.

2. Disconnect wire leads from panel components.

3. Release one (1) nail holding the control panel assembly to the oven flange.

4. Remove control panel assembly and slide upward.

5 . Now, individual components can be removed. NOTE: 1. Before attaching a new key unit, remove remaining

Page 24

R-3C57

TURNTABLE MOTOR REMOVAL

Coil

Gap

Rotor

Bracket

Stator

Groove joint pliers

Shaft

Axis

Stator

These are the position where should be pinched with pliers

Rotor

Side ViewRear View

Shaft

Table

Center of bracket

1. Disconnect oven from power supply.

2. Remove turntable and turntable support from oven cavity.

3. Lay the oven on it's backside. Remove the turntable motor cover by snipping off the material in four corner.

4. Where the corners have been snipped off bend corner areas flat. No sharp edge must be evident after removal of the turntable motor cover.

5. Disconnect wire leads from turntable motor. (See "Positive lock connector removal")

6. Remove two (2) screws holding turntable motor to oven cavity.

7. Now the turntable motor is free.

8. After replacement use the one (1) screw to fit the turntable motor cover.

NOTE: The one (1) screw to fit the turntable motor cover

should be XOTSD40P12000, XOTSD40P10000 or XOTSD40P08000.

COOLING FAN MOTOR REMOVAL

1. CARRY OUT 3D CHECKS.

2. Disconnect the wire leads from the fan motor, thermal cut-out (FAN) and magnetron.

3. Remove two (2) screws holding the chassis support to oven cavity front plate and magnetron. And remove chassis support.

4. Remove two (2) screws holding the magnetron to waveguide flange. And remove the magnetron.

5. Remove one (1) screw holding the fan duct assembly to oven cavity.

6. Release the fan duct assembly from the oven cavity.

7. Remove one (1) screw holding the thermal cut-out angle to the fan motor.

8. 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 grove joint pliers.

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 easily 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 disfigure the bracket by touching with the

pliers.

2) Remove the fan blade from the shaft of the fan motor by pulling 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.

9. Remove the two (2) screws holding the fan motor to the fan duct.

10.Now, the fan motor is free.

INSTALLATION

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

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

1) Hold the center 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.

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 disfigured.

* Make sure that the fan blade rotates smooth after

installation.

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

3. Install the thermal cut-out angle to the fan motor with one (1) screw.

4. Catch two holes of fan duct on two tabs of the waveguide flange.

5. Install the fan duct assembly to the oven cavity with the one (1) screw.

6. Install the magnetron to waveguide flange with two (2) screws.

7. Install one (1) tab of the chassis support to oven cavity front plate and install another tab of it to rear plate. And then screw chassis support to oven cavity front plate and magnetron with two (2) screws.

8. Connect the wire leads to the fan motor, magnetron and thermal cut-out (FAN), referring to the pictorial diagram.

Page 25

R-3C57

Removal

1. CARRY OUT 3D CHECKS.

2. Disconnect the brown and blue wires of the power supply cord from the noise filter.

3. Remove the single (1) screw holding the earth wire of power supply cord.

4. Remove the power supply cord from the rear cabinet.

Re-install

1. Insert the power supply cord into the oven cavity back plate.

2. Connect the brown and blue wires of power supply cord into the terminals of noise filter, referring to pictorial diagram.

3. Re-install the earth wire to bottom plate with one (1) screw.

POWER SUPPLY CORD REPLACEMENT (for New Zealand)

4. CARRY OUT 4R CHECKS.

Note : Step 4 above is important, and it must be done

after replacing power supply cord.

Noise filter

Power supply cord

Brown wire

Blue wire

Green/Yellow wire

Figure C-4(b). Power supply cord replacement

OVEN LAMP AND LAMP SOCKET REMOVAL

Figure C-3. Oven lamp socket

Oven lamp socket

Terminal

Wire lead

Flat type small  screw driver

Terminal hole

1. CARRY OUT 3D CHECKS.

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

3. Bend the tab of the oven cavity holding the lamp socket.

4. Lift up the oven lamp socket.

5. Now, the oven lamp socket is free.

Removal

1. CARRY OUT 3D CHECKS.

2. Remove the one (1) screw holding the green/yellow wire to the bottom plate right.

3. Disconnect the brown wire lead of the power supply cord from the fuse holder.

4. Cut away the connector.

5. Release the power supply cord from the rear cabinet.

6. Now, the power supply cord is free.

Re-install

1. Insert the moulding cord stopper of power supply cord into the square hole of the rear cabinet.

2. Install the earth wire lead of power supply cord to the bottom plate rirgt with one (1) screw and tight the screw.

3. Connect the brown wire lead of power supply cord to the fuse holder correctly, referring to the Pictorial Diagram.

4. Strip the blue wire lead of the power supply cord and white wire lead of the main wire harness for 15mm lengh from their end.

POWER SUPPLY CORD REPLACEMENT (for Australia)

5. Wind the conductor of the blue wire lead of the power supply cord and the conductor of the wire lead of the main wire harness each other.

6. Insert them into the connector. And clamp it.

7. CARRY OUT 4R CHECKS.

15 mm

Connector CE-230

Blue wire lead of power supply cord

Wire lead of the  main wire harness

Conductor:  Stripped portion 

Connector CE-230

Figure C-4(a). Power supply cord replacement

Page 26

R-3C57

1ST. LATCH SWITCH, 2ND. LATCH SWITCH AND MONITOR SWITCH REMOVAL

1. CARRY OUT 3D CHECKS.

2. Disconnect wire leads from the switches.

3. Remove two (2) screws holding latch hook to oven flange.

4. Remove latch hook assembly from oven flange.

5. Push outward on the two (2) retaining tabs holding switch in place.

6. Switch is now free. At this time switch lever will be free, do not lose it.

Re-install

1. Re-install each switch lever and latch switch in its place. The 1st. latch /monitor switches are in the lower position and the 2nd. latch switch is in the upper position.

2. Re-connect wire leads to each switch. Refer to pictorial diagram.

3. Secure latch hook (with two (2) mounting screws) to oven flange.

4. Make sure that the monitor switch is operating properly and check continuity of the monitor circuit. Refer to chapter "Test Procedure" and Adjustment procedure.

1ST. LATCH SWITCH, 2ND. LATCH SWITCH AND MONITOR SWITCH ADJUSTMENT

If the 1st. latch switch, 2nd. latch switch and monitor switch do not operate properly due to a misadjustment, the following adjustment should be made.

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

2. With door closed, adjust latch hook by moving it back and forth, and up and down. In and out play of the door allowed by the upper and lower position of the latch hook should be less than 0.5mm. The vertical position of the latch hook should be adjusted so that the 1st. latch switch and 2nd. latch switch are activated with the door closed.

3. Secure the screws with washers firmly.

4. Check the 2nd. latch switch operation. If the 2nd. latch switch has not activated with the door closed, loosen screw and adjust the latch hook position.

After adjustment, check the following.

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

2. The 2nd. latch switch and stop switch interrupt the circuit before the door can be opened.

3. Monitor switch contacts close when door is opened.

4. Re-install outer case and check for microwave leakage around door with an approved microwave survey meter. (Refer to Microwave Measurement Procedure.)

Figure C-5. Latch Switch Adjustments

LATCH HEADS

LATCH HOOK

2ND. LATCH SWITCH

MONITOR  SWITCH

SWITCH LEVER

STOP SWITCH

1ST. LATCH SWITCH

DOOR REPLACEMENT

door frame.

10.Release door panel from nine (9) tabs of door frame by sliding door panel downward.

11.Now, door panel with sealer film is free.

12.Tear sealer film from door panel.

13.Now, door panel is free.

14.Slide latch head upward and remove it from door frame with releasing latch spring from door frame and latch head.

15.Now, latch head and latch spring are free.

16.Remove door screen from door frame by releasing two (2) tabs.

17.Now, door screen is free.

REMOVAL

1. Disconnect oven from power supply.

2. Push the open button and open the door slightly.

3. Insert an putty knife (thickness of about 0.5mm) into the gap between the choke cover and corner portion of door frame as shown Figure C-6 to free engaging parts.

4. Try the principles of the lever and lift up the choke cover by inserting a putty knife as shown Figure C-6.

5. Release choke cover from door panel.

6. Now choke cover is free.

7. Release two (2) pins of door panel from two (2) hole of upper and lower oven hinges by lifting up.

8. Now, door panel is free from oven cavity.

9. Remove the two (2) screws holding the door panel to the

Page 27

R-3C57

Putty Knife

Door frame

Choke Cover

1



Figure C-6. Door Disassembly

RE-INSTALL

1. Re-install door screen to door frame by fitting two (2) tabs of door frame to two (2) holes of door screen.

2. Re-install latch spring to the head. Re-install latch spring to the door frame. Re-install latch head to the door frame.

3. Re-install door panel to door frame by fitting nine (9) tabs of door frame to nine (9) holes of door panel.

4. Hold the door panel to the door frame with two (2) screws.

5. Put sealer film on door panel. Refer to "Sealer Film" about how to handle new one.

6. Catch two (2) pins of door panel on two (2) hole of upper and lower oven hinges.

7. Re-install choke cover to door panel by pushing.

Note: After any service to the door; (A) Make sure that door sensing switch and secondary

interlock switch are operating properly. (Refer to chapter "Test Procedures".).

(B) An approved microwave survey meter should be

used to assure compliance with proper microwave radiation emission limitation standards.

After any service, make sure of the following :

1. Door latch heads smoothly catch latch hook through latch holes and that latch head goes through center of latch hole.

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

3. Door is positioned with its face pressed toward cavity face plate.

4. Check for microwave leakage around door with an approved microwave survey meter. (Refer to Microwave Measurement Procedure.)

Note: The door on a microwave oven is designed to act as

an electronic seal preventing the leakage of microwave energy from oven cavity during cook

cycle. This function does not require that door be airtight, moisture (condensation)-tight or light-tight. Therefore, occasional appearance of moisture, light or sensing of gentle warm air movement around oven door is not abnormal and do not of themselves, indicate a leakage of microwave energy from oven cavity.

UPPER  OVEN HINGE

DDOR PANEL

CHOKE  COVER

LOWER  OVEN  HINGE

Figure C-7. Door Replacement

SEALER FILM

Installation

1. Put the adhesive tape on the backing film of the sealer film as shown in Fig. C-8.

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

Figure C-8. Sealer film

Page 28

R-3C57

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-3C57

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

1.07µ

AC2100V

TURNTABLE MOTOR

FAN MOTOR

OVEN LAMP

STOP

SWITCH

MONITOR SWITCH

CONTROL

UNIT

THERMAL

CUT-OUT

145˚(MG)

THERMAL 

CUT-OUT

95˚C (FAN)

1ST.

LATCH

SWITCH

EARTH

BLU

BRN

240V/50Hz

TTM

N.O.

RY-1

G-Y

COM.

FUSE

M8A

THERMAL

CUT-OUT

145˚C (OVEN)

RY-2

2ND.

LATCH

SWITCH

MONITOR

RESISTOR

0.8/20W

POWER TRANSFORMER

MAGNETRON

H.V. RECTIFIER

ASYMMETRIC

RECTIFIER

CAPACITOR

1.07µ

AC2100V

TURNTABLE MOTOR

FAN MOTOR

OVEN LAMP

STOP

SWITCH

MONITOR SWITCH

CONTROL

UNIT

THERMAL

CUT-OUT

145˚(MG)

THERMAL 

CUT-OUT

95˚C (FAN)

1ST.

LATCH

SWITCH

TTM

N.O.

RY-1

COM.

THERMAL

CUT-OUT

145˚C (OVEN)

RY-2

2ND.

LATCH

SWITCH

MONITOR

RESISTOR

0.8/20W

EARTH

BLU

BRN

230-240V/50Hz

G-Y

FUSE

M8A

LINE CROSS CAPACITOR

0.068µ/AC250V

NOISE SUPPRESSION COIL

LINE BYPASS

CAPACITOR

0.0022µ/AC250V

LINE BYPASS

CAPACITOR

0.0022µ/AC250V

NOTE: " " indicates components with potentials above 250V.

Page 30

R-3C57

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)

NOTE: " " indicates components with potentials above 250V.

POWER TRANSFORMER

MAGNETRON

H.V. RECTIFIER

ASYMMETRIC

RECTIFIER

CAPACITOR

1.07µ

AC2100V

TURNTABLE MOTOR

FAN MOTOR

OVEN LAMP

STOP

SWITCH

MONITOR SWITCH

CONTROL

UNIT

THERMAL

CUT-OUT

145˚(MG)

THERMAL 

CUT-OUT

95˚C (FAN)

1ST.

LATCH

SWITCH

EARTH

BLU

BRN

240V/50Hz

TTM

N.O.

RY-1

G-Y

COM.

FUSE

M8A

THERMAL

CUT-OUT

145˚C (OVEN)

RY-2

2ND.

LATCH

SWITCH

MONITOR

RESISTOR

0.8/20W

POWER TRANSFORMER

MAGNETRON

H.V. RECTIFIER

ASYMMETRIC

RECTIFIER

CAPACITOR

1.07µ

AC2100V

TURNTABLE MOTOR

FAN MOTOR

OVEN LAMP

STOP

SWITCH

MONITOR SWITCH

CONTROL

UNIT

THERMAL

CUT-OUT

145˚(MG)

THERMAL 

CUT-OUT

95˚C (FAN)

1ST.

LATCH

SWITCH

TTM

N.O.

RY-1

COM.

THERMAL

CUT-OUT

145˚C (OVEN)

RY-2

2ND.

LATCH

SWITCH

MONITOR

RESISTOR

0.8/20W

EARTH

BLU

BRN

230-240V/50Hz

G-Y

FUSE

M8A

LINE CROSS CAPACITOR

0.068µ/AC250V

NOISE SUPPRESSION COIL

LINE BYPASS

CAPACITOR

0.0022µ/AC250V

LINE BYPASS

CAPACITOR

0.0022µ/AC250V

Page 31

R-3C57

Figure S-1. Pictorial Diagram (for Australia)

HIGH 

VOLTAGE

CAPACITOR

H.V.

RECTIFIER

HIGH VOLTAGE COMPONENTS

OVEN LAMP 

AND SOCKET

MAGNETRON

COM.

MONITOR

SWITCH

COM.

N.O.

N.C.

2ND

LACTH

SWITCH

1ST 

LATCH

SWITCH

TURNTABLE

MOTOR

NOTE:

Neutral (WHT) wire must

be connected to the

terminal with black mark

on the oven light socket.

CONTROL UNIT

HIGH VOLTAGE

TRANSFORMER

COM.

LSI

CN-B

RY1

CN-G

RY2

GRN

GRY

CN-A

12345

WHT

BLK

WHT

RED

GRY

ORG

BLK

RED

BLK

GRY

WHT

RED

GRY

BLK

GRY

BLACK MARK

BLKBLK

THERMAL CUT-OUT

(OVEN)

FAN MOTOR

RED

BLK

WHT

GRY

CN-B

CN-A

WHT

BLU

BRN

POWER

SUPPLY

CORD

EARTH

NEUTRAL

LIVE

GRN

BLK

ORG

GRY

STOP

SWITCH

COM.

GRY

GRN

G

/

WHT

THERMAL CUT-OUT

(FAN)

BLKRED

THERMAL CUT-OUT

(MAGNETRON)

WHT

ASYMMETRIC

RECTIFIER

MONITOR

RESISTOR

BLK

GRY

RED

BRN

FUSE

M8A

HIGH VOLTAGE

WIRE A

Page 32

R-3C57

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

HIGH 

VOLTAGE

CAPACITOR

H.V.

RECTIFIER

HIGH VOLTAGE COMPONENTS

OVEN LAMP 

AND SOCKET

MAGNETRON

COM.

MONITOR

SWITCH

COM.

N.O.

N.C.

2ND

LACTH

SWITCH

1ST 

LATCH

SWITCH

TURNTABLE

MOTOR

NOTE:

Neutral (WHT) wire must

be connected to the

terminal with black mark

on the oven light socket.

CONTROL UNIT

HIGH VOLTAGE

TRANSFORMER

COM.

LSI

CN-B

RY1

CN-G

RY2

GRN

GRY

CN-A

12345

WHT

BLK

WHT

RED

GRY

ORG

BLK

RED

BLK

GRY

WHT

RED

GRY

BLK

GRY

BLACK MARK

BLKBLK

THERMAL CUT-OUT

(OVEN)

FAN MOTOR

RED

BLK

WHT

GRY

CN-B

CN-A

WHT

BLU

BRN

POWER

SUPPLY

CORD

EARTH

NOISE FILTER

M8A

NEUTRAL

LIVE

GRN

BLK

ORG

GRY

STOP

SWITCH

COM.

GRY

GRN

G

/

WHT

THERMAL CUT-OUT

(FAN)

BLKRED

THERMAL CUT-OUT

(MAGNETRON)

WHT

ASYMMETRIC

RECTIFIER

WHT

RED

MONITOR

RESISTOR

BLK

GRY

HIGH VOLTAGE

WIRE A

Page 33

R-3C57

Figure S-2. Contrl Panel Circuit

5432 1

0987 6

STOP

CLEAR

LESS

POWER

LEVEL

HELP

Frozen

Dinner

CLOCK

TIMER

COM

AC240V

50Hz

FAN MOTOR

TURNTABLE

MOTOR 

OVEN LAMP

POWER

TRANSFORMER

DOOR

SWITCH

VRS1

(J1)

a b

563

D1 S1NB10

R10 47K

R11 56K

D20 D21

RY1

RY2

(J2)

Q21

KRC243M

Q22

DTA143ES

D22

(J5)

(J3) (J4)

(J6)

R6 12 1/2W

R31 4.7K

C30

R30 15K

D30

C1 0.1µ/50V

C2 330µ/35V

C20 0.1µ/50V

C21

10µ/35V

Q20

KRA101M

C10

0.01µ/25V

R7 150

R2

820

1/2W

R3

820

1/2W

R41 3.3K

SP40

(D)

C3 47µ/16V

C6

47µ/16V

C7

0.1µ/50V

R5

4.7K

Q1

2SA933

R4

ZD2

HZ4C3

R60

CF1 4MHz

(A)

(B)

(C)

R74 100K R73 100K

R75 100K

R72 4.7K

R71 4.7K

R70 4.7K

(A) (B) (C)

Q72Q71Q70

R51 15K

R52 15K

R53 15K

R54 15K

R50

150K x 4

C50

330p x 4

Q70~Q72

2SA933

(D)

R40 1K

D50

G12

G11

G10

G8 G7 G6 G5 G4 G3 G2 G1

D51

D52

D53

D54

D57

KEY UNIT

CONTROL UNIT

IC1 IZA655DR

Vdsp

R00

R01

R02

R03

TEST

RST

OSC1

OSC2

GND

AVSS

AN0

AN1

AN2

R33

R40

R41

R42

R43

AVCC

VCC

R22

R21

R20

R13

D8D7D6D5D4

BUZZ

INT

R23

R12

R11

R10

R83

R82

R81

R80

F

P

1

P

F

P

2

3

4

5

6

7

FLUORESCENT DISPLAY TUBE

COOK KG DEF HELP

Note : IF NOT SPECIFIED, 1/4W ± 5%

IF NOT SPECIFIED, 1SS270A

IF NOT SPECIFIED, 0.01µF/16V

1 28

P

J27 150

J35

510

D55

AUTO

START

REHEAT

MEAT

VEGE-

TABLES

Pasta

Meal

MEMORY1MEMORY

RICE

PASTA

DEFROST

INSTANT

COOK

START

Page 34

R-3C57



Q22

Figure S-3. Printed Wiring Board

Page 35

R-3C57

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 QSW-MA110WRE0 1st. 2nd. and stop switches 3 AK 1- 2 QSW-MA111WRE0 Monitor switch 1 AK 1- 3 RV-MZA197WRE0 Magnetron 1 BN 1- 4 RTHM-A080WRE0 Thermal cut-out 145˚C 2 AP 1- 5 FH-DZA046WRK0 High voltage rectifier assambly 1 AW 1- 6 RC-QZA172WRE0 High voltage capacitor 1 AY 1- 7 RMOTEA265WRE0 Cooling fan motor 1 AZ 1- 8 RTHM-A072WRE0 Thermal cut-out 95˚C 1 AM 1- 9 QACCAA036WRE0 Power supply cord (for Australia) 1 AX 1- 9 QACCAA037WRE0 Power supply cord (for New Zealand) 1 AW 1-10 QFS-CA010WRE0 Fuse (M8A) 1 AE 1-11 FPWBFA272WRK0 Noise filter (for New Zealand) 1 AS 1-12 QSOCLA011WRE0 Oven lamp socket 2 AH 1-13 RLMPTA029WRE0 Oven lamp 1 AK 1-14 RMOTDA169WRE0 Turntable motor 1 AW 1-15 RR-WZA003WRE0 Monitor resistor 0.8Ω 20W 1 AG 1-16 RTRN-A480WRE0 Power transformer 1 BP 1-17 QFSHDA019WRE0 Fuse holder (for Australia) 1 AH

CABINET PARTS

2- 1 GCABUA522WRT0 Outer case cabinet 1 AT 2- 2 FDAI-A171WRY0 Bottom plate right 1 AT 2- 3 GDAI-A261WRW0 Bottom plate left 1 AP 2- 4 GLEGPA019WRE0 Foot 4 AD

CONTROL PANEL PARTS

3- 1 CPWBFA649WRK0 Control unit (New Zealand only) 1 BM 3- 1A QCNCMA234DRE0 3-pin connector (CN-A) 1 AC 3- 1B QCNCMA275DRE0 2-pin connector (CN-B) 1 AB 3- 1C QCNCWA057DRE0 12-pin connector (CN-G) 1 AF 3- 1D RV-KXA069DRE0 Fluorescent display tube 1 AX C1 RC-KZA087DRE0 Capacitor 0.1uF 50V 1 AB C2 VCEAB31VW337M Capacitor 330uF 35V 1 AC C3 VCEAB31CW476M Capacitor 47uF 16V 1 AA C4-5 VCKYD11CY103N Capacitor 0.01uF 16V 2 AH C6 VCEAB31CW476M Capacitor 47uF 16V 1 AA C7 RC-KZA087DRE0 Capacitor 0.1uF 50V 1 AB C10 VCKYB11EX103N Capacitor 0.01uF 25V 1 AA C20 VCEAB31HW104M Capacitor 0.1uF 50V 1 AB C21 VCEAB31VW106M Capacitor 10uF 35V 1 AB C30 VCKYD11CY103N Capacitor 0.01uF 16V 1 AH C50 RMPTEA009DRE0 Capacitor array 330pF x 4 1 AE CF1 RCRS-A012DRE0 Ceramic resonator (CST4.00MGW) 1 AD D1 RSRCDA013DRE0 Diode bridge (S1NB10) 1 AG D2 VHD1SS270A/-1 Diode (1SS270ATA) 1 AA D20-22 VHD1SS270A/-1 Diode (1SS270ATA) 3 AA D30 VHD1SS270A/-1 Diode (1SS270ATA) 1 AA D50-55 VHD1SS270A/-1 Diode (1SS270ATA) 6 AA D57 VHD1SS270A/-1 Diode (1SS270ATA) 1 AA IC1 RH-IZA655DRE0 LSI 1 AT Q1 VS2SA933S//-3 Transistor (2SA933) 1 AB Q20 VSKRA101M//-3 Transistor (KRA101M) 1 AB Q21 VSKRC243M//-3 Transistor (KRC243M) 1 AB Q22 VSDTA143ES/1B Transistor (DTA143ES) 1 AB Q70-72 VS2SA933S//-3 Transistor (2SA933) 3 AB R2-3 VRD-B12HF821J Resistor 820 ohm 1/2W 2 AD R4 VRD-B12EF102J Resistor 1.0k ohm 1/4W 1 AA R5 VRD-B12EF472J Resistor 4.7k ohm 1/4W 1 AA R6 VRD-B12HF120J Resistor 12 ohm 1/2W 1 AB R7 VRD-B12EF151J Resistor 150 ohm 1/4W 1 AA R10 VRD-B12EF473J Resistor 47k ohm 1/4W 1 AA R11 VRD-B12EF563J Resistor 56k ohm 1/4W 1 AA R30 VRD-B12EF153J Resistor 15k ohm 1/4W 1 AA R31 VRD-B12EF472J Resistor 4.7k ohm 1/4W 1 AA R40 VRD-B12EF102J Resistor 1.0k ohm 1/4W 1 AA R41 VRD-B12EF332J Resistor 3.3k ohm 1/4W 1 AA R50 RR-DZA143DRE0 Resistor array 150k ohm x 4 1 AC R51-54 VRD-B12EF153J Resistor 15k ohm 1/4W 4 AA R60 VRD-B12EF105J Resistor 1M ohm 1/4W 1 AA

* *

∆

Page 36

R-3C57

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

∆

R70-72 VRD-B12EF472J Resistor 4.7k ohm 1/4W 3 AA R73-75 VRD-B12EF104J Resistor 100k ohm 1/4W 3 AA (J27) VRD-B12EF151J Resistor 150 ohm 1/4W 1 AA (J35) VRD-B12EF511J Resistor 510 ohm 1/4W 1 AA RY1 RRLY-A080DRE0 Relay (OJ-SS-124LM) 1 AG RY2 RRLY-A076DRE0 Relay (OMIF-S-124LM) 1 AK SP40 RALM-A014DRE0 Buzzer (PKM22EPT-THAI) 1 AG T1 RTRNPA098DRE0 Transformer 1 AT VRS1 RH-VZA032DRE0 Varistor (10G471K) 1 AE ZD2 VHEHZ4C3///-1 Zener diode (HZ4C-3) 1 AA 3- 2 FPNLCB167WRK0 Control panel frame with key unit 1 AZ 3- 2-1 FUNTKA692WRE0 Key unit 1 AY 3- 3 JBTN-A921WRF0 Open button 1 AF 3- 4 MSPRCA050WRE0 Open button spring 1 AB 3- 5 XEPSD30P08XS0 Screw : 3mm x 8mm 1 AA

OVEN PARTS

4- 1 PHOK-A095WRF0 Latch hook 1 AN 4- 2 LBNDKA095WRP0 Capacitor holder 1 AM 4- 3 NFANJA029WRE0 Fan blade 1 AL 4- 4 PDUC-A599WRP0 Fan duct 1 AK 4- 5 FOVN-A330WRT0 Oven cavity 1 BD 4- 6 LANGFA171WRP0 Chassis support 1 AG 4- 7 MLEVPA194WRF0 Switch lever 1 AG 4- 8 NCPL-A045WRF0 Coupling 1 AH 4- 9 PCOVPA275WRE0 Waveguide cover 1 AR 4-10 PCUSGA339WRP0 Cushion 1 AG 4-11 PCUSUA329WRP0 Cushion 1 AC 4-12 PDUC-A597WRF0 Air guide 1 AG 4-13 PFILWA041WRE0 Lamp filter 1 AF 4-14 PPACGA084WRF0 TTM packing 1 AF 4-15 LANGQA368WRP0 Fuse angle (for Australia) 1 AL 4-16 LANGQA343WRP0 Thermal cut-out (Fan) mounting angle 1 AK 4-17 PCUSGA378WRP0 Cushion 1 AL 4-18 PCUSGA388WRP0 Cushion 1 AK 4-19 PCUSUA278WRP0 Cushion 1 AC

DOOR PARTS

5- 1 FDORFA283WRT0 Door panel 1 AY 5- 2 PSHEPA382WRE0 Sealer film 1 AH 5- 3 GCOVHA342WRF0 Choke cover 1 AM 5- 4 GWAKPA348WRR0 Door frame 1 AN 5- 5 HPNL-A586WRE0 Door screen 1 AQ 5- 6 LSTPPA139WRF0 Latch head 1 AF 5- 7 MSPRTA084WRE0 Latch spring 1 AB 5- 8 XCTSD40P06000 Screw; 4mm x 6mm 2 AA

MISCELLANEOUS

6- 1 FROLPA057WRK0 Roller stay 1 AQ 6- 2 NTNT-A051WRE0 Turntable tray 1 AR 6- 3 TINSEA653WRR0 Operation manual 1 AR 6- 4 FW-VZB122WRE0 Switch harness 1 AP 6- 5 FW-VZB466WRE0 Main wire harness (for Australia) 1 AW 6- 5 FW-VZB467WRE0 Main wire harness (for New Zealand) 1 AW 6- 6 QW-QZA187WRE0 High voltage wire A 1 AM 6- 7 LHLDWA011WRE0 Purse lock “M” 1 AB 6- 8 TCAUHA214WRR0 Caution label 1 AC 6- 9 TLABMA489WRR0 Menu label 1 AD 6-10 TSPCNC192WRR0 Name plate (for Australia) 1 AC 6-10 TSPCNC196WRR0 Name plate (for New Zealand) 1 AD 6-11 PZET-A012WRE0 Thermal insulator 1 AB 6-12 QTANP0020YBE0 Connector (for Australia) 1 AA 6-13 TCAUHA185WRR0 Micro caution (for New Zealand) 1 AD 6-14 TGAN-A079WRR0 Warrant card (for New Zealand) 1 AF

SCREWS,NUTS AND WASHERS

7- 1 XFPSD40P08K00 Screw : 4mm x 8mm 9 AA 7- 2 XFPSD30P06000 Screw : 3mm x 6mm 2 AA 7- 3 XHTSD40P08RV0 Screw : 4mm x 8mm 3 AA 7- 4 XHTSD40P08000 Screw; 4mm x 8mm 1 AA 7- 5 XOTSD40P12RV0 Screw : 4mm x 12mm 14 AA

Page 37

R-3C57

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

7- 6 XOTSD40P12000 Screw : 4mm x 12mm 9 AA 7- 7 XVPSD40P20000 Screw; 4mm x 20mm 1 AA 7- 8 XFPSD30P10000 Screw; 3mm x 10mm 1 AA

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

PACKING AND ACCESSORIES

DOOR PROTECTION SHEET SPADPA204WRE0

TOP PAD ASSEMBLY FPADBA311WRK0

PLASTIC BAG SSAKHA034WRE0

Not replaceable items.

PACKING CASE SPAKCC592WRE0 (Australia) SPAKCC606WRE0 (New Zealand)

BOTTOM PAD ASSEMBLY FPADBA312WRK0

6- 2 TURNTABLE TRAY

6- 3 OPERATION MANUAL

6- 1 TURNTABLE SUPPORT

TRAY PACK SPADFA257WRE0

INTO THE OVEN CAVITY

Page 38

R-3C57

OVEN AND CABINET PARTS

2-1

7-5

7-6

1-13

1-12

4-13

4-12

4-11

1-4

7-1

1-3

7-6

6-8

7-6

7-3

1-9

4-2

7-2

1-5

1-1

7-6

4-6

7-3

1-4

4-10

1-1

1-2

7-5

4-1

7-1

4-3

7-1

4-4

6-2

6-1

1-7

1-16

6-11

4-7

2-4

7-6

7-57-5

2-2

2-4

7-5

2-3

4-9

7-1

1-14

4-14

4-8

4-5

1-10

7-1

1-11

7-4

1-17

7-8

1-10

For New  Zealand

For  Australia

4-18

4-19

7-1

1-9

4-17

1-15

7-3

1-1

7-1

4-15

4-16

1-8

7-2

7-7

7-6

6-13

6-9

1-6

Page 39

R-3C57

CONTROL PANEL PARTS

5-2

5-3

5-1

5-5

5-6

5-7

5-4

5-8

DOOR PARTS

Actual wire harness may be different than illustration.

6-6

6-4

6-12

6-7

6-5

MISCELLANEOUS

3- 1

3-2-1

3- 3

3- 4

3- 2

6-10

3- 5

Page 40

R-3C57

'95SHARP CORP. (07K0.820E) Printed in Australia