Sharp R-380d User manual

R-380D

SHARP CORPORATION

SERVICE MANUAL

S7006R380DPJ/

MICROWAVEOVEN

MODEL R-380D

In interests of user-safety the oven should be restored to its

original condition and only parts identical to those specified

should be used.

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 .............................................................................................................................14

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE ........................................................... 18

MICROWAVE MEASUREMENT .................................................................................................................... 24

WIRING DIAGRAM ......................................................................................................................................... 25

PICTORIAL DIAGRAM ................................................................................................................................... 26

POWER UNIT CIRCUIT ..................................................................................................................................27

CPU UNIT CIRCUIT ........................................................................................................................................28

PRINTED WIRING BOARD .............................................................................................................................29

PARTS LIST ................................................................................................................................................... 30

DINNER

PLATE

CASSEROLE

SOUP

PIZZA

POWER

LEVEL

LESS

STOP

CLEAR

INSTANT COOK

START

CLOCK

TIMER

RICE

SENSOR INSTANT REHEAT

SENSOR COOK

1234

6789

DEFROST COOK

HELP

Info Display HELP

VEGETABLES

RICE/PASTA

MEAT DESSERTS

EASY

DEFROST

SLOW

COOK

EXPRESS

DEFROST

R-380D

SERVICEMANUAL

MICROWAVE OVEN

R-380D

GENERAL IMPORTANT INFORMATION

ThisManualhasbeenpreparedtoprovideSharpCorp.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.

Serviceengineersshouldnot beexposed tothe 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.

(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 micro-

wave exposure, by themselves, or when they are damaged,

loosened or removed.

SHARP CORPORATION

OSAKA, JAPAN

PRODUCT SPECIFICATIONS

APPEARANCE VIEW

OPERATING SEQUENCE

FUNCTION OF IMPORTANT

COMPONENTS

SERVICING AND

TROUBLESHOOTING CHART

TEST PROCEDURE

TOUCH CONTROL PANEL

ASSEMBLY

COMPONENT REPLACEMENT

AND ADJUSTMENT PROCEDURE

MICROWAVE MEASUREMENT

WIRING DIAGRAM

PARTS LIST

R-380D

ITEM DESCRIPTION

Power Requirements 230 - 240 Volts

50 Hertz

Single phase, 3 wire earthed

Power Consumption 1.6kW

Power Output 1100 watts nominal of RF microwave energy (IEC Test Procedure)

Operating frequency 2450 MHz

Case Dimensions Width 520 mm

Height 302 mm including foot

Depth 436 mm

Cooking Cavity Dimensions Width 374 mm

Height 227 mm

Depth 399 mm

Turntable diameter 335 mm

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

HELP pad

SENSOR INSTANT REHEAT pads

SENSOR COOK pads

EXPRESS DEFROST pad

EASY DEFROST pad

SLOW COOK pad

MORE('), LES(") pads

NUMBER pads

POWER LEVEL pad

CLOCK pad

TIMER pad

STOP/CLEAR pad

INSTANT COOK/START pad

Set Weight Approx. 17 kg

PRODUCT SPECIFICATIONS

GENERAL INFORMATION

WARNING

THIS APPLIANCE MUST BE EARTHED

IMPORTANT

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

GREEN-AND-YELLOW : EARTH

BLUE : NEUTRAL

BROWN : LIVE

R-380D

APPEARANCEVIEW

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 handle

9. Touch control panel

10.Digital readout

11.Waveguide cover

12.Power supply cord

13.Rating label

14.Turntable tray

15.Turntable support

TOUCH CONTROL PANEL

NOTE:

The directed feature is disabled after three minutes when the oven is not in use. This feature is automatically

enabled when the door is opened and closed or the STOP/ CLEAR pad is pressed.

SOUP

DINNER

PLATE

CASSEROLE

PIZZA

POWER

LEVEL

LESS MORE

STOP

CLEAR

INSTANT COOK

START

CLOCK

TIMER

RICE PIE

SENSOR INSTANT REHEAT

SENSOR COOK

12345

6789

STOP/CLEAR PAD

Press to clear during programming.

Press once to stop operation of oven

during cooking; press twice to can-

cel cooking programme.

POWER LEVEL PAD

Press to select microwave power

setting. If not pressed, HIGH is au-

tomatically selected.

INSTANT COOK/START PAD

Press once to cook for 1 minute

on HIGH or increase by 1 minute

multiples each time this pad is

pressed during cooking. Press

start the oven after setting pro-

grammes. (See note.)

HELP PAD

Press to select auto start, child

lock, demonstration modes or info

on pads.

Press to get cooking information.

SENSOR INSTANT REHEAT PADS

Press once to rehaet 1 of 6 popular

menus. (See Note.) EXPRESS DEFROST PAD

Press to select the Express De-

frost menu.

EASY DEFROST PAD

Press to defrost frozen food by

entering quantity.

SENSOR COOK PADS

Press to select a Sensor Cook me-

nus.

MORE( ), LESS ( ) PADS

Press to increase/ decrease the

time in one minute increments dur-

ing cooking or to after the cooking

result for Instant Reheat, Sensor

cook or Easy Defrost modes.

NUMBER PADS

Press to enter cooking times,

clock time, weight or quantity of

food.

SLOW COOK PAD

Press to cook slowly and for a

longer time.

TIMER PAD

Press to set Timer.

CLOCK PAD

Press to set Clock.

Indicator

Display

DEFROSTSENSOR COOK

HELP

Info Display HELP

VEGETABLES

RICE/PASTA

MEAT DESSERTS

EASY

DEFROST

SLOW

COOK

EXPRESS

DEFROST

14 15

7211

R-380D

OPERATION SEQUENCE

OFF CONDITION

Closing the door activates all door interlock switches

(1st. latch switch, 2nd. latch switch and stop switch).

IMPORTANT

Whentheovendoorisclosed,themonitorswitchcontacts

(COM-NC) must be open.

Whenthemicrowaveovenispluggedinawalloutlet,rated

voltage is supplied to the noise filter and the control unit.

Figure O-1 on page 25

1. The display shows "SHARP MICRO-WAVE 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 25

CONNECTED COMPONENTS RELAY

Oven lamp, Fan motor, Turntable motor RY1

Power transformer RY2

1. Ratedvoltage issupplied tothe primarywindingof 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

magnetronfilamentandthehighvoltage(2000volts)is

sentto thevoltage doublingcircuit, whereit isdoubled

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

energyischanneledthroughthewaveguide(transport

channel)into theovencavity,where thefoodis placed

to be cooked.

4. Whenthecookingtimeisup,asignaltoneisheardand

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

(NOCOOKING)

1st. latch switch 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.latchswitch,and stopswitcharemadeopen.The

ovenlamp remainson evenif theoven dooris opened

after the cooking cycle has been interrupted, because

therelayRY1staysclosed.Shown inthedisplayisthe

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

cycleofacookingprogram,the1st.latchswitch,2nd.

latchswitchandstopswitchmustopen 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

thecontacts ofthe 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.

ThefuseM10A willblow,becausethe monitorswitch

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 cur-

rent-limitingrelay.Thefollowinglevelsofmicrowavepower

are given.

SETTING;

NOTE: TheON/OFFtimeratiodoesnotexactlycorrespond

to the percentage of microwave power, because

approx. 2 seconds are needed for heating up the

magnetron filament.

SENSOR COOKING CONDITION

Using the SENSOR COOK or SENSOR INSTANT RE-

HEAT function, the foods are cooked or reheated without

figuring time, power level or quantity. When the oven

senses enough steam from the food, it relays the informa-

tiontoitsmicroprocessorwhichwillcalculatetheremaining

cooking time and power level needed for best results.

When the food is cooked, water vapor is developed. The

sensor “senses” the vapor and its resistance increases

gradually. When the resistance reaches the value set

according to the menu, supplementary cooking is started.

The time of supplementary cooking is determined by ex-

perimentwitheachfoodcategoryandinputtedintotheLSI.

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%

R-380D

An example of how sensor works:

1. Potatoes at room temperature. Vapor is emitted very

slowly.

2. Heatpotatoes.Moistureandhumidityisemittedrapidly.

You can smell the aroma as it cooks.

3. Sensor detects moisture and humidity and calculates

cooking time and variable power.

Cooking Sequence.

1. Touch each SENSOR COOK or SENSOR INSTANT

REHEATfunctionpadtooperatingthesensorcooking.

(See the operation manual for the proper procedure.)

NOTE: The oven should not be operated on SENSOR

COOK or SENSOR INSTANT REHEAT

immediately after plugging in the unit. Wait two

minutes before cooking on SENSOR COOK or

SENSOR INSTANT REHEAT.

2. The coil of shut-off relay (RY-1) is energized, the

turntable motor, oven lamp and cooling fan motor are

turned on, but the power transformer is not turned on.

3. After about 16 seconds, the cook relay (RY-2) is

energized. The power transformer is turned on,

microwaveenergyisproducedandfirststageisstarted.

The16 secondsisthe coolingtimerequired to remove

any vapor from the oven cavity and sensor.

NOTE: During this first stage, do not open the door or

touch STOP/CLEAR pad.

4. When the sensor detects the vapor emitted from the

food,thedisplayswitchesovertotheremainingcooking

time and the timer counts down to zero.

At this time, the door may be opened to stir food, turn

it or season, etc.

5. Whenthetimerreacheszero,anaudiblesignalsounds.

Theshut-offrelayandcookrelayarede-energizedand

the power transformer, oven lamp, etc. are turned off.

6. Opening the door or touching the STOP/CLEAR pad,

the time of day will reappear on the display and the

oven will revert to an OFF condition.

MICROWAVE

AH SENSOR

R-380D

FUNCTION OF IMPORTANT COMPONENTS

OVEN THERMAL CUT-OUT

Thethermal cut-out,located onthetop ofthe ovencavity,

is designed to prevent damage to the oven by fire. If the

foods load is overcooked, by either error in cook time or

defect in the control unit, the thermal cut-out will open.

Undernormaloperation,theoventhermalcut-outremains

closed.However,whenabnormallyhightemperaturesare

reached within the oven cavity, the oven thermal cut-out

will open at 125˚C, causing the oven to shut down. The

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

MAGNETRON THERMAL CUT-OUT

The thermal cut-out located near the magnetron is de-

signed to prevent damage to the magnetron if an over

heated condition develops in the tube due to cooling fan

failure,obstructedairguide,dirtyorblockedairintake,etc.

Under normal operation, the thermal cut-out remains

closed.However,whenabnormallyhightemperaturesare

reached within the magnetron, the thermal cut-out will

open at 95˚C causing the oven to shut down, when the

magnetronhascooledto 75˚C,thethermalcut-outcloses

and cook cycle will resume.

TURNTABLE MOTOR

Theturntablemotordrivestheturntablerollerassemblyto

rotate the turntable.

FAN MOTOR

Thefanmotordrivesabladewhichdrawsexternalcoolair.

Thiscool airisdirected throughthe air vanessurrounding

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 ex-

hausted through the exhausting air vents at the oven

cavity

NOISE FILTER

The noise filter prevents the radio frequency interference

that might flow back in the power circuit.

DOOR OPEN MECHANISM

Thedoor isopened bypulling thedoor,refer tothe Figure

D-1.

Figure D-1. Door Open Mechanism

1ST.LATCHSWITCH,2ND.LATCHSWITCHAND

STOP SWITCH

1. Whentheovendoorisclosed,thecontacts (COM-NO)

must be closed.

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

NO) must be opened.

MONITOR SWITCH

1. Whentheovendoorisclosed,thecontacts(COM-NC)

must be opened.

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

NC) must be closed.

3. Iftheovendoorisopenedandthecontacts(COM-NO)

ofthe1st.latchswitchand2nd.latchswitchfailtoopen,

the fuse M10A blows simultaneously with closing the

contacts (COM-NC) of the monitor switch.

CAUTION: BEFORE REPLACING A BLOWN FUSE

M10ATESTTHE1ST.LATCHSWITCH, 2ND.

LATCH SWITCH MONITOR SWITCH AND

MONITOR RESISTOR FOR PROPER OP-

ERATION.

MONITOR RESISTOR 0.8Ω20W

The monitor resistor prevents the fuse M10A bursting

when the fuse M10A blows due to the operation of the

monitor switch.

HIGH VOLTAGE FUSE

Thehighvoltagefuseblowswhenthehighvoltagerectifier

or magnetron is shorted.

FUSE M10A

1. ThefuseM10Ablowswhenthecontacts(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. If the wire harness or electrical components are short-

circuited, this fuse M10A blows to prevent an electric

shock or fire hazard.

Latch Hook

Stop Switch

2nd. Latch

Switch

Latch

Heads

Door

Monitor Switch

1st. Latch

Switch

R-380D

SERVICING

WARNING TO SERVICE PERSONNEL

Microwaveovenscontaincircuitrycapableofproducingveryhighvoltageandcurrent,contactwithfollowingparts

of the high voltage circuit will result in electrocution. High voltage capacitor, Power transformer, Magnetron, High

voltage rectifier assembly, High voltage fuse, High voltage harness.

REMEMBER TO CHECK 3D

1) Disconnect the supply.

2) Door opened, and wedged open.

3) Discharge the high voltage capacitor.

WARNING: AGAINST THE CHARGE OF THE

HIGH-VOLTAGE CAPACITOR

Thehigh-voltagecapacitorremainschargedabout

60 seconds after the oven has been switched off.

Wait for 60 seconds and then short-circuit the

connectionofthehigh-voltagecapacitor(thatis,of

the connecting lead of the high-voltage rectifier)

against the chassis with the use of an insulated

screwdriver.

Sharprecommendthatwhereverpossiblefault-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

ovenchassis.(Useinsulationtapeifnecessary.)When

the testing is completed carry out 3D checks and

reconnect the leads to the primary of the power trans-

former.

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 ovensshould notbe runempty. Totest 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

(timeratzero)carefullycheckthatthewaterisnowhot.

If the water remains cold carry out 3D checks and re-

examine the connections to the component being

tested.

When troubleshooting the microwave oven, it is helpful to

follow the Sequence of Operation in performing the

checks.Manyofthepossiblecausesoftroublewillrequire

that a specific test be performed. These tests are given a

procedure letter which will be found in the "Test

Procedure"section.

When all service work is completed, and the oven is fully assembled, the microwave power output should be

checked and microwave leakage test should be carried out.

TROUBLESHOOTING GUIDE

IMPORTANT: If the oven becomes inoperative because

of a blown fuse M10A in the 1st. latch

switch - 2nd. latch switch - monitor switch

- monitor resistor circuit, check the 1st.

latch switch, 2nd. latch switch, monitor

switchand monitorresistorbeforereplac-

ing the fuse M10A.

R-380D

CK = Check / RE = Replace

MAGNETRON

POWER TRANSFORMER

H.V. RECTIFIER ASSEMBLY

HIGH VOLTAGE CAPACITOR

1ST. LATCH SWITCH

2ND. LATCH SWITCH

STOP SWITCH

MONITOR SWITCH

MONITOR RESISTOR

THERMAL CUT-OUT 95˚C /125˚C

FAN MOTOR

TURNTABLE MOTOR

FUSE M10A

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

HIGH VOLTAGE FUSE

AH SENSOR

Homefuseblowswhenpower

supply cord is plugged into

wall outlet.

FUSE M10A blows when

power supply cord is plugged

into wall outlet.

Display does not show any-

thingwhenpowersupply cord

is plugged into wall outlet.

Display doesnotoperateprop-

erly when STOP/CLEAR pad

is touched.

Oven lamp does not light at

door opened. (Display ap-

pears.)

Oven does not start when the

START pad is touched. (Dis-

play appears)

Ovenlampdoesnotlight(Dis-

play appears.)

Fan motor does not operate.

(Display appears.)

Turntable motor assembly

doesnotoperate.(Displayap-

pears.)

Oven or any electrical parts

does not stop when cooking

timeis0orSTOP/CLEARpad

is touched.

Oven seems to be operating

butlittleornoheatisproduced

in oven load. (Microwave

power level is set at HIGH)

Oven does not seems to be

operating properly when ME-

DIUM HIGH, MEDIUM, ME-

DIUM LOW or LOW is set.

(Oven operates properly at

HIGH and then the STOP/

CLEAR pad is touched the

oven stops.)

Ovengoesintocookcyclebut

shutsdownbeforeendofcook-

ing cycle.

AH sensor does not end dur-

ingSensorCookingcondition.

(Ovendoesnotshutoffaftera

cup of water is boiling by sen-

sor cooking.)

Oven stops at 16 sec. after

starting.

TEST PROCEDURE A B C

EEE EG FHH I LMNO

RECK CK RECK CKCK CK CK

JKP

CONDITION PROBLEM

POSSIBLE CAUSE

AND

DEFECTIVE PARTS

CONDITION

OFF

CONDITION

SENSOR

COOKING

CONDITION

R-380D

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

AMAGNETRON TEST

NEVER TOUCH ANY PART IN THE CIRCUIT WITH YOUR HAND OR AN INSULATED TOOL

WHILE THE OVEN IS IN OPERATION.

CARRY OUT 3D CHECK.

Isolatethe magnetronfrom high voltagecircuit byremovingall leadsconnected tofilamentterminal.

Totestforanopencircuitfilamentuseanohmmetertomakeacontinuitytestbetweenthemagnetron

filament terminals, the meter should show a reading of less than 1 ohm.

To test for short circuit filament to anode condition, connect ohmmeter between one of the filament

terminalsandthecaseofthemagnetron(ground).Thistestshouldbeindicatedaninfiniteresistance.

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 IEC

testprocedure,i.e.itcanbemeasuredbyusingwaterloadhowmuchitcanbeabsorbedbythewater

load.Tomeasurethemicrowaveoutputpowerinthemicrowaveoven,therelationofcalorieandwatt

is used. When P(W) heating works for t(second), approximately P x t/4.187 calorie is generated. On

theotherhand, if thetemperatureofthe water withV(ml)rises∆T(˚C)during thismicrowaveheating

period, the calorie of the water is V x ∆T.

The formula is as follows;

P x t / 4.187 = V x ∆T+ 0.55 x mc (T2-T0)

(W) = 4.187 x V x ∆T / t + 0.55 x mc (T2-T0)/t

Our condition for water load is as follows:

Room temperature (T0) ... around 20°C Power supply Voltage..............Rated voltage

Water load..................................1000 g Initial temperature (T1) ...................... 10±1°C

Heating time.............................. 38 sec. Mass of container (mc) ......................... 330 g

T2............................ Final Temperature P = 110 x ∆T + 0.55 x mc (T2-T0)/38

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 of the test.

3. Temperature of the water

The initial temperature of the water is (10±1)˚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. Selectstirringdevicesandmeasuringinstrumentsinordertominimizeadditionorremovalofheat.

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

thermometer.

7. The water load must be (1000±5) g.

8. “t”ismeasuredwhilethemicrowavegeneratorisoperatingatfullpower.Magnetronfilamentheat-

up 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.

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.

R-380D

Room temperature .................. To = 21˚C Initial temperature................. T1 = 11°C

Temperature after (38 + 2) = 40 sec. ................................................................ T2 = 21°C

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

Measured output power

The equation is “P = 110 x ∆T” ........................................... P = 110 x 10°C = 1100 Watts

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

1000g

T1˚C T2˚C

Heat up for 40 sec.

BPOWER TRANSFORMER TEST

WARNING: Highvoltagesandlargecurrentsarepresentatthesecondarywindingandfilament

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. 1.0 Ω

b. Secondary winding ...............approx. 87 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.

CHIGH VOLTAGE RECTIFIER ASSEMBLY TEST

HIGH VOLTAGE RECTIFIER TEST

CARRY OUT 3D CHECKS.

IsolatethehighvoltagerectifierassemblyfromtheHVcircuit.Thehighvoltagerectifier canbetested

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.Thenormalresistanceisinfiniteinonedirectionandmorethan100kΩintheotherdirection.

CARRY OUT 4R CHECKS.

NOTE: FOR MEASUREMENT OF THE RESISTANCE OF THE RECTIFIER, THE BATTERIES OF

THEMEASURINGINSTRUMENTMUSTHAVEAVOLTAGEATLEAST6VOLTS,BECAUSE

OTHERWISE AN INFINITE RESISTANCE MIGHT BE SHOWN IN BOTH DIRECTIONS.

HIGH VOLTAGE RECTIFIER

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

CAUTION: 1°C CORRESPONDS TO 110 WATTS REPEAT MEASUREMENT IF THE POWER IS

INSUFFICIENT.

R-380D

CARRY OUT 3D CHECKS.

Disconnect the leads from the monitor resistor. 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.

GMONITOR RESISTOR TEST

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

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 MΩbecause 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.

ESWITCH 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 COM; Common terminal

Released Open circuit Short circuit NO; Normally open terminal

Depressed Short circuit Open circuit NC; Normally close terminal

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

CARRY OUT 4R CHECKS.

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: Temperature fuse and 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 125˚C This is not resetable type. Above 125˚C Closed circuit.

Thermal cut-out 95˚C Below 75˚C Above 95˚C Closed circuit.

If incorrect readings are obtained, replace the temperature fuse or thermal cut-out.

Anopencircuitthermal cut-out95˚C(MG)indicatesthatthe magnetronhasoverheated,thismay be

duetoresistrictedventilation,coolingfanfailureorafaultconditionwithinthemagnetronorHVcircuit.

An open circuit thermal cut-out 125˚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.

F TEMPERATURE FUSE AND THERMAL CUT-OUT TEST

R-380D

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

CARRY OUT 3D CHECKS.

Disconnect the leads from the motor.

Usinganohmmeter,checktheresistancebetweenthetwoterminalsasdescribedinthetablebelow.

Table: Resistance of Motor

Motors Resistance

Fan motor Approximately 390 Ω

Turntable motor Approximately 12 kΩ

If incorrect readings are obtained, replace the motor.

CARRY OUT 4R CHECKS

HMOTOR WINDING TEST

CARRY OUT 3D CHECKS.

1. If the fuse M10A 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 M10A is blown when the door is opened, check the 1st. latch switch, 2nd. latch switch,

monitor switch and monitor resistor.

Ifthe fuseM10A isblownby incorrectdoor switchingreplace the defectiveswitch(s) andthe fuse

M10A.

CARRY OUT 4R CHECKS.

CAUTION: ONLY REPLACE FUSE M10A WITH THE CORRECT VALUE REPLACEMENT

IBLOWN FUSE M10A

JNOISE FILTER TEST

CARRY OUT 3D CHECKS.

Disconnect the leads from the terminals of the noise

filter. Using an ohmmeter, check between the termi-

nals as described in the following table.

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.

LCx L

WHT

RED

L (min) Cx ±20% Cy ±20%

600µH 0.068µF 0.0022µF

CARRY OUT 3D CHECKS.

Ifthehighvoltagefuse isblown,therecouldbeashortin the highvoltage rectifierorthemagnetron.

Check them and replace the defective parts and high voltage fuse.

CARRY OUT 4R CHECKS.

CAUTION: ONLY REPLACE THE HIGH VOLTAGE FUSE WITH THE CORRECT VALUE RE-

PLACEMENT

K HIGH VOLTAGE FUSE TEST

If incorrect readings are obtained, replace the monitor resistor.

CARRY OUT 4R CHECKS.

R-380D

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

M KEY UNIT TEST

If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon cable

ismakinggoodcontact,verifythatthedoorsensingswitch(stopswitch)operatesproperly;thatisthe

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 cable that connects the key unit to the control

unitand makesurethe doorsensingswitch isclosed(either closethedoor orshort the doorsensing

switch connector). Use the key unit matrix indicated on the control panel schematic and place a

jumperwirebetween thepinsthatcorrespondto theSTOP/CLEARpadmaking 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.

L TOUCH CONTROL PANEL ASSEMBLY TEST

ThetouchcontrolpanelconsistsofcircuitsincludingsemiconductorssuchasLSI,ICs,etc.Therefore,

unlike conventional microwave ovens, proper maintenance cannot be performed with only a

voltmeterandohmmeter.Inthisservicemanual,thetouchcontrolpanelassemblyisdivided intotwo

units, Control Unit and Key Unit, and also the Control Unit is divided into two units, CPU Unit and

Power Unit, and troubleshooting by unit replacement is described according to the symptoms

indicated.

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 Unit.

Thefollowingsymptomsindicateadefectivecontrolunit.Beforereplacingthecontrolunit,perform

the Key unit test (Procedure M) 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.

G 9

G10

G11

G12

G13

G14

G 8

54321

MEAT CLOCK

HELP RICE

STOP

CLEAR

VEGETABLES

POWER

LEVEL

INSTANT

COOK

START

LESS SLOW

COOK

DESSERTS

TIMER SOUP

PIE

RICE/

PASTA EASY

DEFROST

EXPRESS

DEFROST

DINNER

PLATE

PIZZA

CASSEROLE

9876

G 7 G 6 G 5 G 4 G 3 G 2 G 1

NRELAY TEST

RemovetheoutercaseandcheckvoltagebetweenPinNo2ofthe2-pinconnector(A)andthenormal

open terminal of the relay RY1 on the power unit with an A.C. voltmeter. The meter should indicate

230 - 240 volts, if not check oven circuit.

R-380D

To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary

onthePWB,thisfoil patternactsasafuse.Ifthefoil patternisopen,followthetroubleshootingguide

given below for repair.

Problem: POWER ON, indicator does not light up.

CARRY OUT 3D CHECKS.

STEPS OCCURRENCE CAUSE OR CORRECTION

The rated AC voltage is not present between

1 Pin No. 2 of the 2-pin connector (A) and the Check supply voltage and oven power cord.

normal open terminal of the relay RY1.

2The rated AC voltage is present to 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.

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

NOTE: *At the time of making these repairs,

makeavisualinspectionofthevaristor.

Checkfor burned damageand exam-

inethetransformerwithatesterforthe

presence of layer short-circuit (check

the primary coil resistance). If any ab-

normal condition is detected, replace

the defective parts.

CARRY OUT 4R CHECKS.

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

OPROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED WIRING BOARD

(PWB) IS OPEN

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 ......... Checkdiodewhichisconnectedtotherelaycoil.Ifdiodeisgood,

control unit is defective.

RELAY SYMBOL OPERATIONAL VOLTAGE CONNECTED COMPONENTS

RY1 APPROX. 25.0V D.C. Oven lamp / Turntable motor / Cooling fan motor

RY2 APPROX. 24.0V D.C. Power transformer

CARRY OUT 4R CHECKS.

RY1

VRS1

RY3

(J1)

Checking the initial sensor cooking condition

(1) The oven should be plugged in at least two minutes before sensor cooking.

(2) Room temperature should not exceed 35˚C.

(3)Theunitshouldnotbeinstalled in anyareawhereheatandsteamaregenerated.Theunitshould

not be installed, for example, next to a conventional surface unit. Refer to the "INSTALLATION

Instructions" .

(4)Exhaust ventsare providedon theback ofthe unit forproper coolingand airflow inthe cavity.To

permitadequateventilation,besuretoinstallsoasnottoblockthesevents.Thereshouldbesome

space for air circulation.

(5) Be sure the exterior of the cooking container and the interior of the oven are dry. Wipe off any

moisture with a dry cloth or paper towel.

(6) The Sensor works with food at normal storage temperature. For example, chicken pieces would

be at refrigerator temperature and canned soup at room temperature.

(7) Avoid using aerosol sprays or cleaning solvents near the oven while using Sensor settings. The

sensor will detect the vapour given of by the spray and turn off before food is properly cooked.

P AH SENSOR TEST

R-380D

(8) If the sensor has not detected the vapour of the food, ERROR will appear and the oven will shut off.

Water load cooking test

Makesuretheovenhasbeenpluggedinatleastfiveminutesbeforecheckingsensorcookoperation.

The cabinet should be installed and screws tightened.

(1) Fill approximately 200 milliliters (7.2 oz) of tap water in a 1000 milliliter measuring cup.

(2) Place the container on the center of tray in the oven cavity.

(3) Close the door.

(4) Touch PIZZA pad of SENSOR INSTANT REHEAT once. Now, the oven is in the sensor cooking

condition and "PIZZA", "SENSOR" and "REHEAT" will appear in the display.

(5) The oven will operate for the first 16 seconds, without generating microwave energy.

NOTE: ERROR will appear if the door is opened or STOP/CLEAR pad is touched during first stage

of sensor cooking.

(6) After approximately 16 seconds, microwave energy is produced, and the display should start to

countdown theremainingcooking time,andoven should turnoff after wateris boiling (bubbling).

Iftheovendoesnotturnoff,replacetheAHsensororcheckthecontrolunit,refertoexplanationbelow.

TESTING METHOD FOR AH SENSOR AND/OR CONTROL UNIT

To determine if the sensor is defective, the simplest method is to replace it with a new replacement

sensor.

(1) Disconnect oven from power supply and remove outer case.

(2) Discharge the high voltage capacitor.

(3) Remove the AH sensor.

(4) Install the new AH sensor.

(5) Re-install the outer case.

(6)Reconnecttheoventothepowersupplyandcheckthesensorcookoperationproceedasfollows:

6-1. Fill approximately 200 milliliters (7.2 oz) of tap water in a 1000 milliliter measuring cup.

6-2. Place the container on the center of tray in the oven cavity.

6-3. Close the door.

6-4. Touch PIZZA pad once.

6-5. The control panel is in automatic sensor operation.

6-6. The display will start to count down the remaining cooking time, and the oven will turn off

automatically after the water is boiling (babbling).

If new sensor dose not operate properly, the problem is with the control unit.

CHECKING CONTROL UNIT

(1) Disconnect oven from power supply and remove outer case.

(2) Discharge the high voltage capacitor.

(3) Disconnect the wire leads from the cook relay.

(4) Disconnect the sensor connector that is mounted to lower portion of control panel.

(5) Then connect the dummy resistor circuit (see fig.) to the sensor connector of control panel.

(6)Reconnecttheoventothepowersupplyandcheckthesensorcookoperation,proceedasfollows:

6-1. Touch PIZZA pad once.

6-2. The control panel is in the sensor cooking operation.

6-3. After approximately 30 seconds, push plunger of select switch. This condition is same as

judgement by AH sensor.

6-4. After approximately 3 seconds, the display shows " ENJOY YOUR PIZZA ".

If the above is not the case, the control unit is probably defective.

If the above is proper, the AH sensor is probably defective.

R1,R2 : 22Ω±1% 1/2W

R3 : 4.3kΩ±5% 1/4W

R4 : 1MΩ±5% 1/4W

Sensor Dummy Resistor Circuit

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

Plunger

COM

COM NO

R3 R4

F-1

F-2

F-3

To connector (F)

on Control Unit.

CONNECTOR

R-380D

LSI(IXA049DR)

The I/O signal of the LSI(IXA049DR) is detailed in the following table.

TOUCH CONTROL PANEL ASSEMBLY

OUTLINE OF TOUCH CONTROL PANEL

The touch control section consists of the following units.

(1) Key Unit

(2) Control Unit (The Control Unit consists of Power

Unit and LSI 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 P10-P17.

Whenakeypadistouched,asignaliscompletedthrough

the key unit and passed back to the LSI through AN11,

AN10, AN9, P42, P41 and AN8 to perform the function

that was requested.

Control Unit

Control unit consists of LSI, ACL circuit, indicator circuit,

powersourcecircuit,relaycircuit,buzzercircuit,synchro-

nizing signal circuit, absolute humidity sensor circuit and

back light circuit.

1) ACL

This circuit generates a signal which resets the LSI to

the initial state when power is supplied.

2) Indicator Circuit

This circuit consists of 40 segments and 16 common

electrodes using a Liquid Crystal Display.

The Liquid Crystal Display (LCD) is drived by LCD

driver IC3.

3) Power Source Circuit

This circuit generates voltages necessary in the con-

trol unit from the AC line voltage.

In addition, the synchronizing signal is available in

order to compose a basic standard time in the clock

circuit.

Symbol Voltage Application

VC -5V LSI(IC1)

4) Relay Circuit

A circuit to drive the magnetron, fan motor, turntable

motor and light the oven lamp.

5) Buzzer Circuit

ThebuzzerisresponsivetosignalsfromtheLSItoemit

audible sounds (key touch sound and completion

sound).

6) 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.

7) Stop Switch

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

8) Back Light Circuit

A circuit to drive the back light (Light emitting diodes

LD10-LD19).

9) Absolute Humidity Sensor Circuit

This circuit detects moisture of the cooking food to

allow its automatic cooking.

Pin No. Signal I/O Description

1 AN10 IN Signal coming from touch key.

When either G10 line on key matrix is touched, a corresponding signal out of P10 - P17

will be input into AN10. When no key is touched, the signal is held at "H" level.

2 AN11 IN Signal similar to AN10.

When either G9 line on key matrix is touched, a corresponding signal will be input into

AN11.