r-520lw service manual - justanswer · (c) before turning on microwave power for any service test...

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R - 520LKR-520LW

Intheinterestofuser-safetytheovenshouldberestoredtoitsoriginalconditionandonlypartsidenticaltothosespecifiedshouldbeused.

WARNING TO SERVICE PERSONNEL: Microwave ovens contain circuitry capable of producing very high voltage and current, contact with following parts may result in a severe, possibly fatal, electrical shock. (High Voltage Capacitor, High Voltage Power Transformer, Magnetron, High Voltage Rectifi er Assembly, High Voltage Harness etc..)

TABLE OF CONTENTS PagePRECAUTIONSTOBEOBSERVEDBEFOREANDDURINGSERVICINGTOAVOIDPOSSIBLEEXPOSURETOEXCESSIVEMICROWAVEENERGY..................... INSIDEFRONTCOVERBEFORESERVICING....................................................................................................... INSIDEFRONTCOVERWARNINGTOSERVICEPERSONNEL................................................................................................................. 3MICROWAVEMEASUREMENTPROCEDURE..................................................................................................... 4FOREWORDANDWARNING............................................................................................................................... 5PRODUCTSPECIFICATIONS............................................................................................................................... 6GENERALINFORMATION.................................................................................................................................... 6OPERATION........................................................................................................................................................... 8TROUBLESHOOTINGGUIDE............................................................................................................................. 1TESTPROCEDURE............................................................................................................................................ 13TOUCHCONTROLPANEL.................................................................................................................................. 3COMPONENTREPLACEMENTANDADJUSTMENTPROCEDURE................................................................. 9PICTORIALDIAGRAM......................................................................................................................................... 36CONTROLUNITCIRCUIT................................................................................................................................... 37PRINTEDWIRINGBOARD.................................................................................................................................. 38PARTSLIST........................................................................................................................................................ 39PACKINGANDACCESSORIES.......................................................................................................................... 43

S46M260R520LE

R-520LKR-520LW

MICROWAVE OVEN

MODELS

SERVICE MANUAL

SHARP ELECTRONCS CORPORATION Thisdocumenthasbeenpublishedtobeusedforaftersalesserviceonly.

Thecontentsaresubjecttochangewithoutnotice.

ServiceHeadquarters:SharpPlaza,Mahwah,NewJersey,07430-135

R-520LW

R - 520LKR-520LW

PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY(a) Donotoperateorallowtheoventobeoperatedwiththedooropen.(b) Makethefollowingsafetychecksonallovenstobeservicedbeforeactivatingthemagnetronorother

microwavesource,andmakerepairsasnecessary:(1)interlockoperation,()properdoorclosing,(3)sealandsealingsurfaces(arcing,wear,andotherdamage),(4)damagetoorlooseningofhingesandlatches,(5)evidenceofdroppingorabuse.

(c) Beforeturningonmicrowavepowerforanyservicetestorinspectionwithinthemicrowavegeneratingcompartments,checkthemagnetron,waveguideortransmissionline,andcavityforproperalignment,integrity,andconnections.

(d) Anydefectiveormisadjustedcomponentsintheinterlock,monitor,doorseal,andmicrowavegenerationandtransmissionsystemsshallberepaired,replaced,oradjustedbyproceduresdescribedinthismanualbeforetheovenisreleasedtotheowner.

(e) AmicrowaveleakagechecktoverifycompliancewiththeFederalPerformanceStandardshouldbeperformedoneachovenpriortoreleasetotheowner.

BEFORE SERVICINGBeforeservicinganoperativeunit,performamicrowaveemissioncheckasper theMicrowaveMeasurementProcedureoutlinedinthisservicemanual.Ifmicrowaveemissionslevel is inexcessofthespecifiedlimit,contactSHARPELECTRONICSCORPORATIONimmediately@1-800-37-477.

Iftheunitoperateswiththedooropen,servicepersonshould1)telltheusernottooperatetheovenand)contactSHARPELECTRONICSCORPORATIONandFoodandDrugAdministration'sCenterforDevicesandRadiologicalHealthimmediately.

Servicepersonnel should informSHARPELECTRONICSCORPORATIONofany certifiedunitfoundwithemissionsinexcessof4mW/cm.Theowneroftheunitshouldbeinstructednottousetheunituntiltheovenhasbeenbroughtintocompliance.

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WARNING TO SERVICE PERSONNELMicrowaveovenscontaincircuitrycapableofpro-ducingveryhighvoltageandcurrent,contactwithfollowingparts may result inasevere,possiblyfatal,electricalshock.(Example)High Voltage Capacitor, High Voltage PowerTransformer, Magnetron, High Voltage RectifierAssembly,HighVoltageHarnessetc..ReadtheServiceManualcarefullyandfollowallinstructions.

Before Servicing

1. Disconnectthepowersupplycord , and thenremoveoutercase.

. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.

WARNING: RISK OF ELECTRIC SHOCK. DISCHARGE THE HIGH-VOLTAGE CAPACITOR BEFORE SERVICING.

Thehigh-voltagecapacitor remainschargedabout60secondsaftertheovenhasbeenswitchedoff.Waitfor60secondsandthenshort-circuittheconnectionofthehigh-voltagecapacitor(thatistheconnectingleadofthehigh-voltagerectifier)againstthechassiswiththeuseofaninsulatedscrewdriver.

Whenevertroubleshootingisperformedthepowersupplymustbedisconnected.Itmay,insomecases,benecessarytoconnectthepowersupplyaftertheoutercasehasbeenremoved,inthisevent:1. Disconnect the power supply cord, and then remove

outercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Disconnect the leads to the primary of the power

transformer.5. Ensure that the leads remain isolated from other

components and oven chassis by using insulationtape.

6. Afterthatprocedure,reconnectthepowersupplycord.

When the testing is completed,1. Disconnect the power supply cord, and then remove

outercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Reconnect the leads to the primary of the power

transformer.5. Reinstalltheoutercase(cabinet).6. Reconnectthepowersupplycordaftertheoutercase

isinstalled.7. Runtheovenandcheckallfunctions.

After repairing1. Reconnectallleadsremovedfromcomponentsduring

testing.. Reinstalltheoutercase(cabinet).3. Reconnectthepowersupplycordaftertheoutercase

isinstalled.4. Runtheovenandcheckallfunctions.

Microwaveovensshouldnotbeoperatedempty.Totestforthepresenceofmicrowaveenergywithinacavity,placeacupofcoldwaterontheoventurntable,closethedoorandsetthepowertoHIGHandsetthemicrowavetimerfortwo()minutes.Whenthetwominuteshaselapsed(timeratzero)carefullycheckthatthewaterisnowhot.IfthewaterremainscoldcarryoutBefore Servicingprocedureandre-examinetheconnectionstothecomponentbeingtested.

Whenallserviceworkiscompletedandtheovenisfullyassembled,themicrowavepoweroutputshouldbecheckedandamicrowaveleakagetestshouldbecarriedout.

Don't Touch !Danger High Voltage

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MICROWAVE MEASUREMENT PROCEDURE

A. Requirements:

1) Microwave leakage limit (Power density limit):The power density of microwave radiation emitted by a microwaveovenshouldnotexceed1mW/cmatanypoint5cmormorefromtheexternalsurfaceoftheoven,measuredpriortoacquisitionbyapurchaser,andthereafter(throughtheusefullifeoftheoven),5mW/cmatanypoint5cmormorefromtheexternalsurfaceoftheoven.

) Safetyinterlockswitches: Primaryinterlockrelayswitchshallpreventmicrowaveradiationemissioninexcessoftherequirementasabove mentioned.Secondaryinterlockrelayanddoorsensingswitchshallpreventmicrowaveradiationemissioninexcess

of 5mW/cmatanypoint5cmormorefromtheexternalsurfaceoftheoven.

B. Preparation for testing:Before beginning the actual measurement of leakage, proceed as follows:1) Makesurethattheactualinstrumentisoperatingnormallyasspecifiedinitsinstructionbooklet.Important:Surveyinstrumentsthatcomplywiththerequirementforinstrumentationasprescribedbytheperformancestandardformicrowaveovens,1CFR1030.10(c)(3)(i),mustbeusedfortesting.

) Placetheoventrayintheovencavity.3) Placetheloadof75±15ml(9.8oz)oftapwaterinitiallyat0±5O

C(68OF)inthecenteroftheovencavity. Thewatercontainershallbealowformof600ml(0oz)beakerwithaninsidediameterofapprox.8.5cm(3-1/in.)

andmadeofanelectricallynonconductivematerialsuchasglassorplastic. Theplacingofthisstandardloadintheovenisimportantnotonlytoprotecttheoven,butalsotoinsurethatanyleakage

ismeasuredaccurately.4) SetthecookingcontrolonFullPowerCookingMode.5) Closethedoorandselectacookcycleofseveralminutes.Ifthewaterbeginstoboilbeforethesurveyiscompleted,

replaceitwith75mlofcoolwater.

C. Leakage test:

Closed-doorleakagetest(microwavemeasurement):1) Grasptheprobeofthesurveyinstrumentandholditperpendiculartothegapbetweenthedoorandthebodyofthe

oven.) Movetheprobeslowly,notfasterthan1in./sec.(.5cm/sec.)alongthegap,watchingforthemaximumindicationon

themeter.3) Checkforleakageatthedoorscreen,sheetmetalseamsandotheraccessiblepositionswherethecontinuityofthe

metalhasbeenbreached(eg.,aroundtheswitches,indicator,andvents). Whiletestingforleakagearoundthedoor,pullthedoorawayfromthefrontoftheovenasfarasispermittedbythe

closedlatchassembly.4) Measurecarefullyatthepointofhighestleakageandmakesurethatthehighestleakageisnogreaterthan4mW/cm,

andthattheprimaryinterlockswitch/secondaryinterlockrelaydoesturntheovenOFFbeforeanydoormovement.

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SHARP ELECTRONICS CORPORATION

SHARP PLAZA, MAHWAH,NEW JERSEY 07430-2135

SERVICE MANUAL

MICROWAVE OVENS

R-520LK/R-520LW

FOREWORD

This Manual has been prepared to provide Sharp Electronics Corp.ServicePersonnelwithOperationandServiceInformationfortheSHARPMICROWAVEOVENSR-50LKandR-50LW.

It is recommended that service personnel carefully study the entiretextofthismanualsothattheywillbequalifiedtorendersatisfactorycustomerservice.

Checktheinterlockswitchesandthedoorsealcarefully.Specialatten-tionshouldbegiventoavoidelectricalshockandmicrowaveradiationhazard.

WARNINGNeveroperatetheovenuntilthefollowingpointsareensured:(A)Thedooristightlyclosed.(B)Thedoorbracketsandhingesarenotdefective.(C)Thedoorpackingisnotdamaged.(D)Thedoorisnotdeformedorwarped.(E)Thereisnoothervisibledamagewiththeoven.

Servicingandrepairworkmustbecarriedoutonlybytrainedservicepersonnel.

DANGERCertain initial parts are intentionally not grounded and present a risk of electrical shock only during servicing. Service person-nel - Do not contact the following parts while the appliance is energized; High Voltage Capacitor, Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness; If provided, Vent Hood, Fan assembly, Cooling Fan Motor.

Allthepartsmarked“*”onpartslistareusedatvoltagesmorethan50V.

Removaloftheouterwrapgivesaccesstovoltageabove50V.

Allthepartsmarked“∆”onpartslistmaycauseunduemicrowaveexposure,bythemselves,orwhentheyaredamaged,loosenedorremoved.

PRODUCT DESCRIPTION

GENERAL INFORMATION

OPERATION

TROUBLESHOOTING GUIDE AND TEST PROCEDURE

TOUCH CONTROL PANEL

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE

WIRING DIAGRAM

PARTS LIST

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TOUCH CONTROL PANEL

GENERAL INFORMATION

GROUNDING INSTRUCTIONS

Thisovenisequippedwithathreepronggroundingplug.ItmustbepluggedintoawallreceptaclethatisproperlyinstalledandgroundedinaccordancewiththeNationalElectricalCodeandlocalcodesandordinances.Intheeventofanelectricalshortcircuit,groundingreducestheriskofelectricshockbyprovidinganescapewirefortheelectriccurrent.

WARNING: Improper use of the grounding plug can result in a risk of electric shock.

ElectricalRequirementsTheelectricalrequirementsarea10volt60Hz,AConly,

SPECIFICATION

ITEM DESCRIPTIONPowerRequirements 10Volts 14.3Amperes,1700watts 60Hertz Singlephase,3wiregrounded

PowerOutput 100watts(IECTESTPROCEDURE) Operatingfrequencyof450MHz

CaseDimensions Width4" Height13-3/8" Depth19-1/8"

CookingCavityDimensions Width17-3/8" Height10-1/".0CubicFeet Depth 18-5/8"

ControlComplement TouchControlSystem Clock(1:00-1:59) Timer(0-99min.99seconds)

MicrowavePowerforVariableCooking

RepetitionRate;P-HI.................................................. FullpowerthroughoutthecookingtimeP-90..................................................................... approx. 90%ofFullPowerP-80..................................................................... approx. 80%ofFullPowerP-70..................................................................... approx. 70%ofFullPowerP-60..................................................................... approx. 60%ofFullPowerP-50..................................................................... approx. 50%ofFullPowerP-40..................................................................... approx. 40%ofFullPowerP-30.................................................................... approx. 30%ofFullPowerP-0..................................................................... approx. 0%ofFullPowerP-10..................................................................... approx. 10%ofFullPowerP-0..................................................... Nopowerthroughoutthecookingtime

START/MINUTEPLUSpad,SensorCookpads,Defrostpads,Numberselectionpads,PowerLevelpad,Timer/Clockpad,Stop/Clearpad,KeepWarmPlus,Reheatpads,Popcorn,Nightlight,SensorreheatandHotwater.

OvenCavityLight Yes

SafetyStandard ULListedFCCAuthorized

DHHSRules,CFR,Title1,Chapter1,SubchapterJ

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15or0amp.fusedelectricalsupply.Itisrecommendedthataseparatecircuitservingonlythisappliancebeprovided.Wheninstallingthisap-pliance,observeallapplicablecodesandordinances.A short power-supply cord is provided to reduce risks of becomingentangledinortrippingoveralongercord.Whereatwo-prongedwall-receptacleisencountered,itisthepersonalresponsibilityandobligationofthecustomertocontactaqualifiedelectri-cianandhaveitreplacedwithaproperlygroundedthree-prongedwallreceptacleorhaveagroundingadapterproperlygroundedandpolar-ized.Iftheextensioncordmustbeused,itshouldbea3-wire,15amp.orhigherratedcord.Donotdrapeoveracountertoportablewhereitcanbepulledonbychildrenortrippedoveraccidentally.

CAUTION: DONOTUNDERANYCIRCUMSTANCESCUTORRE-MOVETHEROUNDGROUNDINGPRONGFROMTHISPLUG.

OVEN DIAGRAM1. Onetouchdooropenbutton. Pushtoopendoor.. Doorlatches. Theovenwillnotoperateunlessthe

doorissecurelyclosed.3. Removableturntablesupport.4. Removableturntable. Theturntablewillrotateclockwiseor

counterclockwise.5. Ovenlamp. Itwilllightwhenovenisoperatingor

doorisopened.6. Ovendoorwithsee-throughwindow.7. Ventilationopenings.(Rear)8. Auto-Touchcontrolpanel.9. Timedisplay:Digitaldisplay,99minutes

99seconds.

10.Waveguidecover.11.Powersupplycord

TOUCH CONTROL PANEL

3-ProngedPlug

GroundedReceptacle Box

Grounding Pin

3-Pronged Receptacle

NOTE:The directed features are disabled after one minute when the oven is not in use. These features are automatically enabled when the door is opened and closed or the STOP/ CLEAR pad is pressed.

STARTMINUTE PLUS

CUSTOM HELPCUSTOM HELPPOWERLEVEL

TIMERCLOCKTIMERCLOCK

STOPCLEARSTOP

CLEAR

SENSORREHEATSENSORREHEAT

KEEP WARMPLUS

KEEP WARMPLUS

HOTWATER

HOTWATER

POPCORNPOPCORNFRESH

VEGETABLESFRESH

VEGETABLESBAKED

POTATOESBAKED

POTATOES

BEVERAGEBEVERAGEFROZEN ROLLS/

MUFFINSFROZEN ROLLS/

MUFFINSFRESH ROLLS/

MUFFINSFRESH ROLLS/

MUFFINS

RICERICEFISH

SEAFOODFISH

SEAFOODGROUND

MEATGROUND

MEAT

STEAKS/CHOPS

STEAKS/CHOPS

GROUNDMEAT

GROUNDMEAT

BONE-INPOULTRYBONE-INPOULTRY

BONELESSPOULTRY

BONELESSPOULTRY

FROZENVEGETABLES

FROZENVEGETABLES

CHICKENBREAST

CHICKENBREAST

FROZENENTREESFROZENENTREES

SENSOR COOKSENSOR COOK

REHEATREHEAT

DEFROSTDEFROST

1

6 5

2 10

119

7

8

3

4

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OPERATION

DESCRIPTION OF OPERATING SEQUENCE

Thefollowingisadescriptionofcomponentfunctionsdur-ingovenoperation.

OFF CONDITIONClosingthedooractivatesthedoorsensingswitchandpri-maryinterlockswitch.(Inthiscondition,themonitorswitchcontactsareopened.)Whenovenispluggedin,10voltsA.C.issuppliedtothecontrolunit.(FigureO-1).1. Thedisplaywillshowflashing"88:88". Tosetanyprogramorsettheclock,youmustfirsttouch

theSTOP/CLEARpad.Thedisplaywillclear,and":"willappear.

COOKING CONDITIONProgramdesiredcookingtimebytouchingtheNUMBERpads.Program thepower level by touching thePOWERLEVELpadandthenaNumberpad.WhentheSTARTpadistouched,thefollowingoperationsoccur:

1. The contacts of relays are closed and componentsconnectedtotherelaysareturnedonasfollows.

(Fordetails,refertoFigureO-)

RELAY CONNECTEDCOMPONENTS

RY-1 ovenlamp/turntablemotor/fanmotor

RY- powertransformer

. 10voltsA.C.issuppliedtotheprimarywindingofthepowertransformerandisconvertedtoabout3.3voltsA.C.outputonthefilamentwinding,andapproximately370voltsA.C.onthehighvoltagewinding.

3. The filament winding voltage heats the magnetronfilamentandtheH.V.windingvoltageissenttoavoltagedoublercircuit.

4. Themicrowaveenergyproducedbythemagnetronischannelledthroughthewaveguideintothecavityfeed-box,andthenintothecavitywherethefoodisplacedtobecooked.

5. Upon completion of the cooking time, the powertransformer, oven lamp, etc. are turned off, and thegenerationofmicrowaveenergyisstopped.TheovenwillreverttotheOFFcondition.

6. Whenthedoorisopenedduringacookcycle,themonitorswitch,doorsensingswitch,primaryinterlockswitch,relay(RY1)andsecondaryinterlockrelayareactivatedwiththefollowingresults.Thecircuitstotheturntablemotor,thecoolingfanmotor,andthehighvoltagecomponentsarede-energized,theovenlampremainson,andthedigitalread-outdisplaysthetimestillremaininginthecookcyclewhenthedoorwasopened.

7. Themonitorswitchelectricallymonitorstheoperationoftheprimaryinterlockswitchandsecondaryinterlock

relayandismechanicallyassociatedwiththedoorsothatitwillfunctioninthefollowingsequence.

(1)When the door opens from the closed position, thesecondary interlockrelay(RY)andprimary interlockswitch open their contacts. And contacts of the relay(RY1)remainsclosed.Thenthemonitorswitchcontactsclose.

()When thedoor is closed from theopenposition, themonitor switch contactsopenfirst.Then the contactsoftheprimaryinterlockswitchanddoorsensingswitchclose.Andcontactsoftherelay(RY1)open.

Iftheprimaryinterlockswitchandsecondaryinterlockrelay(RY)failwiththecontactsclosedwhenthedoorisopened,theclosingofthemonitorswitchcontactswillformashortcircuitthroughthemonitorfuse,primaryinterlockswitch,relay(RY1)andsecondaryinterlockrelay(RY),causingthemonitorfusetoblow.

POWER LEVEL P-0 TO P-90 COOKINGWhenVariable Cooking Power is programmed, the 10voltsA.C.issuppliedtothepowertransformerintermittentlythroughthecontactsofrelay(RY-)whichisoperatedbythecontrolunitwithina3secondtimebase.Microwavepoweroperationisasfollows:

VARI-MODE ONTIME OFFTIME

Power10(P-HI) 3sec. 0sec. (100%power) Power9(P-90) 30sec. sec. (approx.90%power) Power8(P-80) 6sec. 6sec. (approx.80%power) Power7(P-70) 4sec. 8sec. (approx.70%power) Power6(P-60) sec. 10sec. (approx.60%power) Power5(P-50) 18sec. 14sec. (approx.50%power) Power4(P-40) 16sec. 16sec. (approx.40%power) Power3(P-30) 1sec. 0sec. (approx.30%power) Power(P-0) 8sec. 4sec. (approx.0%power) Power1(P-10) 6sec. 6sec. (approx.10%power) Power0(P-0) 0sec. 3sec. (0%power) Note: TheON/OFFtimeratiodoesnotcorrespondwiththe

percentageofmicrowavepower,becauseapprox.secondsareneededforheatingofthemagnetronfilament.

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SENSOR COOKING CONDITIONUsingtheSENSORfunction,foodiscookedwithoutfigur-ingtime,powerlevelorquantity.Whentheovensensesenoughsteamfromthefood,itrelaystheinformationtoitsmicroprocessorwhichwillcalculatetheremainingcookingtimeandpowerlevelneededforbestresults.Whenthefoodiscooked,watervaporisdeveloped.thesensor"senses"thevaporanditsresistanceincreasegradually.Whentheresistancereachesthevaluesetaccordingtothemenu,supplementarycookingisstarted.Thetimeofsupplementarycookingisdeterminedbyexperi-mentwitheachfoodcategoryandinputtedintotheLSI.Anexampleofhowsensorworks:(Potatoes)

1. Potatoesatroomtemperature.Vaporisemittedveryslowly.

MICROWAVE

.HeatPotatoes.Moistureandhumidityisemittedveryrapidly.Youcansmellthearomaasitcooks.

MICROWAVEAH SENSOR

3.Sensordetectsmoistureandhumidityandcalculatescookingtimeandvariablepower.

Cooking Sequence.1. TouchoneoftheSENSORpads.

NOTE:Theovenshouldnotbeoperatedonsensor immediatelyafterpluggingintheunit.WaittwominutesbeforecookingonSENSOR.

. Thecoilofshut-offrelay(RY-1)isenergized,theturntablemotorareturnedon,butthepowertransformerisnotturnedon.

3. After about 16 seconds, the cook relay (RY-) isenergized. The power transformer is turned on,microwaveenergyisproducedandfirststageisstarted.The16secondsisthecoolingtimerequiredtoremoveanyvaporfromtheovencavityandsensor.

NOTE: During this first stage, do not open the door ortouch STOP/CLEARpad.

4. Whenthesensordetectsthevaporemittedfromthefood,thedisplayswitchesovertotheremainingcookingtimeandthetimercountsdowntozero.

At this time, thedoormaybeopenedtostir, turnorseasonfood.

5. Whenthetimerreacheszero,anaudiblesignalsounds.Theshut-offrelayandcookrelayarede-energizedandthepowertransformer,ovenlamp,etc.areturnedoff.

6. OpeningthedoorortouchingtheSTOP/CLEARpad,thetimeofthedaywillreappearonthedisplayandtheovenwillreverttoanOFFcondition.Whenthetimerreacheszero,anaudiblesignalsounds.

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FigureO-OvenSchematic-CookingCondition

FigureO-1OvenSchematic-OffCondition

SCHEMATICNOTE:CONDITIONOFOVEN1.DoorClosed.CLOCKAPPEARSONDISPLAY

SCHEMATIC

3.VARIABLECOOKINGCONTROL"HIGH"

.COOKINGTIMEPROGRAMMED1.DOORCLOSEDNOTE:CONDITIONOFOVEN

4."START"PADTOUCHED

Note:*Indicatescomponent

NOTES:1.CIRCUITS SUBJECT TO CHANGE WITHOUT NOTICE.2.TERMINAL WITH PROJECTION OR OPPOSITE BLUE MARK ON LAMP SOCKET

MUST BE CONNECTED TO NEUTRAL WIRE.3. ONLY CERTAIN MODELS USE THE ABSOLUTE HUMIDITY SENSOR.4. POWER TRANSFORMER TOP (FINISH LEAD) TERMINAL MUST BE CONNECTED TO THE NEUTRAL (WHT) WIRE.

CAVITYTEMPERATURE

FUSE

120VAC60Hz

COM.

RED

RED

WHTWHT

WH

T

GRY

BRN

WH

T

WH

T

WHT

ORG

RED

WH

T

WH

T

GRN

N.O.

B2

B1

CONTROL UNIT

MAGNETRONTEMPERATUREFUSE

N.O.

(RY2)

COM.

DOORSENSINGSWITCH

TTM FMOLTURNTABLEMOTOR

FANMOTOR

OVENLAMP

MONITORSWITCH

PRIMARYINTERLOCKSWITCH

POWERTRANSFORMER

MA

GN

ETRO

N

HIGHVOLTAGECAPACITORxx F

ORG

WH

T

SECONDARYINTERLOCK

RELAY

ORG

BRN

ORGORGRED

GRYGRY

GND

WH

T

F3

F2

F1

SENSOR

(RY1)

OVENLAMPRELAY

COM. N.O.

HUMIDITY

COM.

N.C.HIGHVOLTAGERECTIFIER

ORG

H

N

REDRED

PNK

GRN

GRN

GRNGRN

C3

C2

C1

BLK

WH

T

NOISEFILTER

MO

NIT

OR

FUSE

(20A

)

R2

"TO

LOA

D"

"TO

LOA

D"

"TO

SOU

RCE"

"TO

SOU

RCE"

NOTES:1.CIRCUITS SUBJECT TO CHANGE WITHOUT NOTICE.2.TERMINAL WITH PROJECTION OR OPPOSITE BLUE MARK ON LAMP SOCKET

MUST BE CONNECTED TO NEUTRAL WIRE.3. ONLY CERTAIN MODELS USE THE ABSOLUTE HUMIDITY SENSOR.4. POWER TRANSFORMER TOP (FINISH LEAD) TERMINAL MUST BE CONNECTED TO THE NEUTRAL (WHT) WIRE.

CAVITYTEMPERATURE

FUSE

120VAC60Hz

COM.

RED

RED

WHTWHT

WH

T

GRY

BRN

WH

T

WH

T

WHT

ORG

RED

WH

T

WH

T

GRN

N.O.

B2

B1

CONTROL UNIT

MAGNETRONTEMPERATUREFUSE

N.O.

(RY2)

COM.

DOORSENSINGSWITCH

TTM FMOLTURNTABLEMOTOR

FANMOTOR

OVENLAMP

MONITORSWITCH

PRIMARYINTERLOCKSWITCH

POWERTRANSFORMER

MA

GN

ETRO

N

HIGHVOLTAGECAPACITORxx F

ORG

WH

T

SECONDARYINTERLOCK

RELAY

ORG

BRN

ORGORGRED

GRYGRY

GND

WH

T

F3

F2

F1

SENSOR

(RY1)

OVENLAMPRELAY

COM. N.O.

HUMIDITY

COM.

N.C.HIGHVOLTAGERECTIFIER

ORG

H

N

REDRED

PNK

GRN

GRN

GRNGRN

C3

C2

C1

BLK

WH

T

NOISEFILTER

MO

NIT

OR

FUSE

(20A

)

R2

"TO

LOA

D"

"TO

LOA

D"

"TO

SOU

RCE"

"TO

SOU

RCE"

11

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DESCRIPTION AND FUNCTION OF COMPONENTS

DOOR OPEN MECHANISMThedoorisopenedbypushingtheopenbuttononthecon-trolpanel,refertotheFigureD-1.Whentheopenbuttonispushed,theopenbuttonpushesuptheswitchlever,andthentheswitchleverpushesupthelatchhead.Thelatchheadsaremovedupwardand released from latchhook.Nowthedoorwillopen.

Figure D-1. Door Open Mechanism

DOOR SENSING AND PRIMARY INTERLOCK SWITCHESTheprimaryinterlockswitchismountedinthelowerpositionofthelatchhookandthedoorsensingswitchinthesecond-aryinterlocksystemismountedintheupperpositionofthelatchhook.Theyareactivatedbythelatchheadsonthedoor.Whenthedoorisopened,theswitchesinterruptthepowertoallhighvoltagecomponents.Acookcyclecannottakeplaceuntilthedoorisfirmlyclosedtherebyactivatingboth interlock switches.The secondary interlock systemconsistsofthedoorsensingswitchandsecondaryinterlockrelaylocatedonthecontrolcircuitboard.

MONITOR SWITCHThemonitorswitchisactivated(thecontactsopened)bythelatchheadonthedoorwhilethedoorisclosed.Theswitchis intended to render theoven inoperative, bymeansofblowingthemonitorfuse,whenthecontactsofthesecond-aryinterlockrelay(RY)andprimaryinterlockswitchfailtoopenwhenthedoorisopened.

Functions:1. Whenthedoor isopened, themonitorswitchcontact

close(totheONcondition)duetotheirbeingnormallyclosed.Atthistimethesecondaryinterlockrelay(RY)andprimary interlockswitchare intheOFFcondition(contactsopen)duetotheirbeingnormallyopencontactswitches.

. Asthedoorgoestoaclosedposition,themonitorswitchcontacts are first opened and then the door sensingswitchandtheprimaryinterlockswitchcontactsclose.(Onopeningthedoor,eachoftheseswitchesoperateinversely.)

3. Ifthedoorisopened,andthesecondaryinterlockrelay(RY)andprimaryinterlockswitchcontactsfailtoopen,themonitorfuseblowssimultaneouslywithclosingofthemonitorswitchcontacts.

CAUTION: BEFOREREPLACINGABLOWNMONITORFUSETESTTHEDOORSENSINGSWITCH,SECONDARYINTERLOCKRELAY(RY),RE-LAY (RY1),PRIMARY INTERLOCKSWITCHAND MONITOR SWITCH FOR PROPEROPERATION. (REFERTO CHAPTER "TESTPROCEDURE").

NOTE: MONITOR FUSE AND MONITOR SWITCH ARE REPLACED AS AN ASSEMBLY.

TURNTABLE MOTORThe turntablemotor rotates the turntable locatedon thebottomoftheovencavity,sothatthefoodsontheturntablecookevenlyduringcooking.Theturntablemayturnineitherdirection.

COOLING FAN MOTORThecoolingfanmotordrivesabladewhichdrawsexternalcoolair.Thiscoolairisdirectedthroughtheairvanessur-roundingthemagnetronandcoolsthemagnetron.Thisairischanneledthroughtheovencavitytoremovesteamandvaporsgivenofffromtheheatingfoods.Itisthenexhaustedthroughtheexhaustingairventsattheovencavity.

CAVITY TEMPERATURE FUSEThecavitytemperaturefuselocatedonthetopoftheovencavity,isdesignedtopreventdamagetotheovenbyfire.Ifthefoodloadisovercooked,byeithererrorincooktimeordefect in thecontrol unit, thecavity temperature fusewillopen.Undernormaloperation,thecavitytemperaturefuseremainsclosed.However,whenabnormallyhightemperaturesarereachedwithintheovencavity,thecavitytemperaturefusewillopenat30OF(150OC)causingtheoventoshutdown.NOTE:Thisisafuse.Itdoesnotreset.

MONITOR FUSE1. Themonitorfuseblowswhenthecontacts(COM-NO)of

theprimaryinterlockrelay(RY)andsecondaryinterlockswitchremainclosedwiththeovendooropenandwhenthemonitorswitchcloses.

. Ifthewireharnessorelectricalcomponentsareshort-circuited,thismonitorfuseblowstopreventanelectricshockorfirehazard.

Magnetron TEMPERATURE FUSEThemagnetrontemperaturefuselocatednearthemagne-tronisdesignedtopreventdamagetothemagnetronifanoverheatedconditiondevelopsinthetubeduetocoolingfanfailure,obstructedairguide,dirtyorblockedairintake,etc.Undernormaloperation,themagnetrontemperaturefuse

Door S ens ingS witch

Monitor S witch

S witch Lever

P rimary InterlockS witch

Latch Heads

Door

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R - 520LKR-520LW

TROUBLESHOOTING GUIDE

Never touch any part in the circuit with your hand or an uninsulated tool while the power supply is con-nected.

Whentroubleshootingthemicrowaveoven,itishelpfultofollowtheSequenceofOperationinperformingthechecks.Manyofthepossiblecausesoftroublewillrequirethataspecifictestbeperformed.Thesetestsaregivenaprocedureletterwhichwillbefoundinthe"TestProcedure"section.IMPORTANT: Iftheovenbecomesinoperativebecauseofablownmonitorfuse,checkthemonitorswitch,relay(RY1)

secondaryinterlockrelay(RY),doorsensingswitchandprimaryinterlockswitchbeforereplacingthemoni-torfuse.Ifthemonitorfuseisreplaced,themonitorswitchmustalsobereplaced.UsepartFFS-BA016/KITasanassembly.

IMPORTANT: Whenevertroubleshootingisperformedwiththepowersupplycorddisconnected.Itmayin,somecases,benecessarytoconnectthepowersupplycordaftertheoutercasehasbeenremoved,inthisevent:1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Disconnecttheleadstotheprimaryofthepowertransformer.5. Ensurethattheleadsremain isolatedfromothercomponentsandovenchassisbyusinginsulation

tape.6. Afterthatprocedure,reconnectthepowersupplycord.

When the testing is completed1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Reconnecttheleadstotheprimaryofthepowertransformer.5. Reinstalltheoutercase(cabinet).

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R - 520LKR-520LW

A MAGNETRON ASSEMBLY TEST

1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.

TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST

Homefuseorcircuitbreakerblowswhenpowercordispluggedintowallreceptacle

C/Tfuseblowswhenpowercordispluggedintowallreceptacle.

Alllettersandindicatorsdonotap-pearindisplaywhenpowercordisfirstpluggedintowalloutlet.

Display does not operate properlywhenSTOP/CLEARkeyistouched.(Buzzershouldsoundand":"ortimeofdayshouldappearindisplay.)

Ovenlampdoesnotlightwhendoorisopened.

Oven lamp does not go out whendoorisclosed.

Ovenlamplightsbutfanmotorandturntablemotordonotoperate.

Oven does not go into cook cyclewhenSTARTpadistouched

Ovenseemstobeoperatingbutlittleornoheatisproducedinovenload.(Food incompletely cooked or notcookedatallatendofcookcycle.)

Ovengoesintoacookcyclebutex-tremelyunevenheatingisproducedinovenload(food).

OvendoesnotcookproperlywhenprogrammedforCookingPowerP-50mode.(OperatesproperlyonCookingP-HI(HIGH)mode.)

OvengoesintoCOMPUDEFROSTbutfoodisnotdefrostedwell.

AHsensordoesnotendduringsensorcookingcondition.(Ovendoesnotshutoffafteracupofwaterisboilingbysensorcooking)

Ovenstopsat16sec.afterstarting.

OFFCONDITION

PROBLEMCONDITION

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TESTPROCEDURE RERE A B C D E E F F G H RERECK I CKCKCK J K LMN

COOKINGCONDITION

SENSORCOOKINGCONDITION

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CK=Check/RE=Replace

14

R - 520LKR-520LW

B POWER TRANSFORMER TEST

1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Disconnect theprimary input terminals andmeasure the resistanceof the transformerwithan

ohmmeter.Checkforcontinuityofthecoilswithanohmmeter.OntheRx1scale,theresistanceoftheprimarycoilshouldbelessthan1ohmandtheresistanceofthehighvoltagecoilshouldbeapproximately90ohms;theresistanceofthefilamentcoilshouldbelessthan1ohm.

5. Reconnectallleadsremovedfromcomponentsduringtesting.6. Reinstalltheoutercase(cabinet).7. Reconnectthepowersupplycordaftertheoutercaseisinstalled.8. Runtheovenandcheckallfunctions.

(HIGHVOLTAGESAREPRESENTATTHEHIGHVOLTAGETERMINAL,SODONOTATTEMPTTOMEASURETHEFILAMENTANDHIGHVOLTAGE.)


4. Totestforanopenfilament,isolatethemagnetronfromthehighvoltagecircuit.Acontinuitycheckacrossthemagnetronfilamentleadsshouldindicatelessthan1ohm.

5. Totestforashortedmagnetron,connecttheohmmeterleadsbetweenthemagnetronfilamentleadsandchassisground.Thistestshouldindicateaninfiniteresistance.Ifthereislittleornoresistancethemagnetronisgroundedandmustbereplaced.


MICROWAVE OUTPUT POWERThefollowingtestprocedureshouldbecarriedoutwiththemicrowaveoveninafullyassembledcondi-tion(outercasefitted).

HIGHVOLTAGESAREPRESENTDURINGTHECOOKCYCLE,SOEXTREMECAUTIONSHOULDBEOBSERVED.

Poweroutputofthemagnetroncanbemeasuredbyperformingawatertemperaturerisetest.Thistestshouldonlybeusedifabovetestsdonotindicateafaultymagnetronandthereisnodefectinthefollowingcomponentsorwiring:siliconrectifier,highvoltagecapacitorandpowertransformer.Thistestwillrequirea16ounce(453cc)measuringcupandanaccuratemercurythermometerorthermocoupletypetemperaturetester.Foraccurateresults,thefollowingproceduremustbefollowedcarefully:

1. Fillthemeasuringcupwith16oz.(453cc)oftapwaterandmeasurethetemperatureofthewaterwitha thermometeror thermocouple temperature tester.Stir the thermometeror thermocouplethroughthewateruntilthetemperaturestabilizes.Recordthetemperatureofthewater.

. Placethecupofwater intheoven.OperateovenatPOWER10(HIGH)selectingmorethan60secondscooktime.Allowthewatertoheatfor60seconds,measuringwithastopwatch,secondhandofawatchorthedigitalread-outcountdown.

3. Remove the cup from the oven and again measure the temperature, making sure to stir thethermometerorthermocouplethroughthewateruntilthemaximumtemperatureisrecorded.

4. Subtractthecoldwatertemperaturefromthehotwatertemperature.Thenormalresultshouldbe33to6OF(18.6to34.5OC)riseintemperature.Ifthewatertemperaturesareaccuratelymeasuredandtestedfortherequiredtimeperiodthetestresultswillindicateifthemagnetrontubehaslowpoweroutput(lowriseinwatertemperature)whichwouldextendcookingtimeorhighpoweroutput(highriseinwatertemperature)whichwouldreducecookingtime.Becausecookingtimecanbeadjustedtocompensateforpoweroutput,themagnetrontubeassemblyshouldbereplacedonlyifthewatertemperaturerisetestindicatesapoweroutputwellbeyondthenormallimits.Thetestisonlyaccurateifthepowersupplylinevoltageis10voltsandtheovencavityisclean.

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R - 520LKR-520LW


1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Ifthecapacitorisopen,nohighvoltagewillbeavailabletothemagnetron.Disconnectinputleads

andcheckforshortoropenbetweentheterminalsusinganohmmeter. Checkingwithahighohmscale, if thehighvoltagecapacitor isnormal, themeterwill indicate

continuityforashorttimeandshouldindicateanopencircuitoncethecapacitorischarged.Iftheaboveisnotthecase,checkthecapacitorwithanohmmetertoseeifitisshortedbetweeneitheroftheterminalsandcase.Ifitisshorted,replacethecapacitor.


D HIGH VOLTAGE CAPACITOR TEST

E CAVITY TEMPERATURE FUSE TEST

1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Acontinuitycheckacross thecavity temperature fuse terminalsshould indicateaclosedcircuit

unlessthetemperatureofthecavitytemperaturefusereachesapproximately30OF(150OC).Anopencavitytemperaturefuseindicatesoverheatingoftheoven,exchangethecavitytemperaturefuseandcheckinsideofovencavityandforimpropersettingofcookingtimeoroperationofcontrolunit.Checkforrestrictedairflowthroughtheventholesoftheovencavity,especiallythecoolingfanandairguide.


MAGNETRON TEMPERATURE FUSE TEST1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Acontinuitycheckacrossthemagnetrontemperaturefuseterminalsshouldindicateaclosedcircuit

unlessthetemperatureofthemagnetrontemperaturefusereachesapproximately30OF(150OC).Anopenmagnetrontemperaturefuseindicatesoverheatingofthemagnetron.Checkforrestrictedairflowtothemagnetron,especiallythecoolingfanairguide.

5. Reconnectallleadsremovedfromcomponentsduringtesting.6. Reinstalltheoutercase(cabinet).7. Reconnectthepowersupplycordaftertheoutercaseisinstalled.

C HIGH VOLTAGE RECTIFIER TEST

1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Isolatetherectifierfromthecircuit.Usingthehighestohmscaleofthemeter,readtheresistance

acrosstheterminalsandobserve,reversetheleadstotherectifierterminalsandobservemeterreading.Ifashortisindicatedinbothdirections,orifaninfiniteresistanceisreadinbothdirections,therectifierisprobablydefectiveandshouldbereplaced.


NOTE: Be sure to use an ohmmeter that will supply a forward bias voltage of more than 6.3 volts.

16

R - 520LKR-520LW


1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Isolatetheswitchandconnecttheohmmetertothecommon(COM.)andnormallyopen(NO)terminal

oftheswitch.Themetershouldindicateanopencircuitwiththedooropenandaclosedcircuitwiththedoorclosed.Ifimproperoperationisindicated,replacetheprimaryinterlockswitch.


SECONDARY INTERLOCK SYSTEM TEST

DOORSENSINGSWITCH1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Isolate theswitchandconnect theohmmeter to thecommon (COM.)andnormallyopen (NO)

terminaloftheswitch.Themetershouldindicateanopencircuitwiththedooropenandaclosedcircuitwiththedoorclosed.Ifimproperoperationisindicated,replacethedoorsensingswitch.


NOTE: Ifthedoorsensingswitchcontactsfailintheopenpositionandthedoorisclosed,thecoolingfan,turntableandovenlightwillbeactivatedbyRY1.

SECONDARYINTERLOCKRELAY(RY)1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Disconnecttwo()wireleadsfromthemaletabterminalsoftheSecondaryInterlockRelay.Check

thestateoftherelaycontactsusingaohmmeter.Therelaycontactsshouldbeopen.Iftherelaycontactsareclosed,replacethecircuitboardentirelyortherelayitself.


8. Runtheovenandcheckallfunctions.

CAUTION: IFTHETEMPERATUREFUSEINDICATESANOPENCIRCUITATROOMTEMPERATURE,REPLACETEMPERATUREFUSE.

F PRIMARY INTERLOCK SWITCH TEST

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R - 520LKR-520LW


Therefore, unlike conventional microwave ovens, proper maintenance cannot be performed with only a voltmeter and ohmmeter.Inthisservicemanual,thetouchcontrolpanelassemblyisdividedintotwounits,ControlUnitandKeyUnit,andalsotheControlUnitisdividedintotwounits,LSIUnitandPowerUnit,andtroubleshootingbyunitreplacementisdescribedaccordingtothesymptomsindicated.Before testing,

1) Disconnectthepowersupplycord,andthenremoveoutercase.) Openthedoorandblockitopen.3) Dischargehighvoltagecapacitor.4) Disconnecttheleadstotheprimaryofthepowertransformer.5) Ensure that these leads remain isolated fromothercomponentsandovenchassisbyusing

insulationtape.1. KeyUnit. NOTE;

1) Re-installtheoutercase(cabinet).) Reconnectthepowersupplycordaftertheoutercaseisinstalled.3) Runtheovenandcheckallfunctions. Thefollowingsymptomsindicateadefectivekeyunit.a) Whentouchingthepads,acertainpadproducesnosignalatall.b) Whentouchinganumberpad,twofiguresormorearedisplayed.c) Whentouchingthepads,sometimesapadproducesnosignal.

H TOUCH CONTROL PANEL ASSEMBLY TEST

1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Beforeperformingthistest,makesurethattheprimaryinterlockswitchandthesecondaryinterlock

relayareoperatingproperly,accordingtotheaboveSwitchTestProcedure.Disconnectthewirelead from themonitor switch (COM) terminal.Check themonitor switchoperationbyusing theohmmeterasfollows.Whenthedoorisopen,themetershouldindicateaclosedcircuit.Whenthemonitorswitchactuatorispushedbyascrewdriverthroughthelowerlatchholeonthefrontplateoftheovencavitywiththedooropened(inthisconditiontheplungerofthemonitorswitchispushedin), themetershould indicateanopencircuit. If improperoperationis indicated,theswitchmaybedefective.Aftertestingthemonitorswitch,reconnectthewireleadtothemonitorswitch(COM)terminalandcheckthecontinuityofthemonitorcircuit.


G MONITOR SWITCH TEST8. Runtheovenandcheckallfunctions.

P rimaryInterlock S witch Monitor S witch

S crew Driver

Ohmmeter

R ed White/ White

18

R - 520LKR-520LW

. ControlUnit Thefollowingsymptomsindicateadefectivecontrolunit.-1 Inconnectionwithpads.

a)Whentouchingthepads,acertaingroupofpadsdonotproduceasignal.b)Whentouchingthepads,nopadsproduceasignal.

- Inconnectionwithindicatorsa)Atacertaindigit,allorsomesegmentsdonotlightup.b)Atacertaindigit,brightnessislow.c)Onlyoneindicatordoesnotlight.d)Thecorrespondingsegmentsofalldigitsdonotlightup;ortheycontinuetolightup.e)Wrongfigureappears.f)Acertaingroupofindicatorsdonotlightup.g)Thefigureofalldigitsflicker.

-3 Otherpossibleproblemscausedbydefectivecontrolunit.a)Buzzerdoesnotsoundorcontinuestosound.b)Clockdoesnotoperateproperly.c)Cookingisnotpossible.

3. IftheKeyunitortheControlunitisdefective.1) Disconnectthepowersupplycord,andthenremoveoutercase.) Openthedoorandblockitopen.3) Dischargehighvoltagecapacitor.4) ReplacetheControlunitassembly.5) Reconnectallleadsremovedfromcomponentsduringtesting.6) Re-installtheoutercase(cabinet).7) Reconnectthepowersupplycordaftertheoutercaseisinstalled.8) Runtheovenandcheckallfunctions.

4. Whentestingiscompleted,1) Disconnectthepowersupplycord,andthenremoveoutercase.) Openthedoorandblockitopen.3) Dischargehighvoltagecapacitor.4) Reconnectallleadsremovedfromcomponentsduringtesting.5) Re-installtheoutercase(cabinet).6) Reconnectthepowersupplycordaftertheoutercaseisinstalled.7) Runtheovenandcheckallfunctions.


1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Usinganohmmeterandreferringtothekeyunitmatrixindicatedonthecontrolunitcircuit,check

thecircuitbetweenthepinsofthekeyunitthatcorrespondtotheSTOP/CLEARpad.Whenthepadispressed,theohmmetershouldindicateshortcircuit.Whenthepadisreleased,theohmmetershouldindicateopencircuit.Ifincorrectreadingsareobtained,thekeyunitisfaultyandmustbereplaced.Abouttheotherpads,theabovemethodmaybeused.

5. Reconnectallleadsremovedfromcomponentsduringtesting.6. Re-installtheoutercase(cabinet).7. Reconnectthepowersupplycordaftertheoutercaseisinstalled.8. Runtheovenandcheckallfunctions.

I KEY UNIT TEST

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R - 520LKR-520LW

WARNING : Theovenshouldbefullyassembledbeforefollowingprocedure.(1)Openthedoor.()Placeonecupofwaterinthecenteroftheturntabletrayintheovencavity(3)Touchthe"Defrost"padonce.(4)Press"",thenpress"5".(5)Touchthe"START"pad.(6)TheovenisinDefrostcookingcondition.(7)Theovenwilloperateasfollows

MENU 1STSTAGE NDSTAGE 3RDSTAGESTEAKS/CHOPS LEVEL TIME LEVEL TIME LEVEL TIME

0.5lb 60% 0sec. 40% 0sec. 30% 45sec.

(8)Ifimproperoperationisindicated,thecontrolunitisprobablydefectiveandshouldbechecked.


1. Disconnectthepowersupplycord,andthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Disconnecttheleadstotheprimaryofthepowertransformer.5. Ensurethattheseleadsremainisolatedfromothercomponentsandovenchassisbyusinginsulation

tape.6. Afterthatprocedure,re-connectthepowersupplycord.7. RemovetheoutercaseandcheckvoltagebetweenthenormalopenterminaloftherelayRY1and

thenormalopenterminaloftherelayRYonthecontrolunitwithanA.C.voltmeter. Themetershouldindicate10volts,ifnotcheckovencircuit. RY1andRYRelayTest TheserelaysareoperatedbyD.C.voltage CheckvoltageattherelaycoilwithaD.C.voltmeterduringthemicrowavecookingoperation.

DC.voltageindicated Defectiverelay.DC.voltagenotindicated Checkdiodewhichisconnectedtotherelaycoil.Ifdiodeisgood,

controlunitisdefective.

RELAYSYMBOL OPERATIONALVOLTAGE CONNECTEDCOMPONENTS

RY1 Approx.1.0VD.C. Ovenlamp/Turntablemotor/Coolingfanmotor

RY Approx.1.0VD.C. Powertransformer

8.Disconnectthepowersupplycord,andthenremoveoutercase.9.Openthedoorandblockitopen.10.Dischargehighvoltagecapacitor.11.Reconnectallleadsremovedfromcomponentsduringtesting.1.Re-installtheoutercase(cabinet).13.Reconnectthepowersupplycordaftertheoutercaseisinstalled.14.Runtheovenandcheckallfunctions.

K COMPU DEFROST TEST

KeyUnit

J RELAY TEST

PinNO.G1

PinNO.G13

Keyunitribboncable

Keyunit(MembraneSwitch)frontview

G10

G11

G12

G13

G9

G8 G7 G6 G5 G4 G3 G2 G1

9

3

6

25

80

14

7

TIMER

CLOCK

RICE

POPCORN

MINUTE PLUSSTARTSTOP

CLEARBAKED

POTATOES

FROZENENTREES

BEVERAGE

GROUNDMEAT

(SENSOR COOK)

HOT WATER

FRESHVEGETABLES

FROZENVEGETABLES

POWERLEVEL

CUSTOMHELP

KEEP WARM

PLUS

STEAKS/CHOPS

SENSORREHEAT

FISHSEAFOOD

GROUNDMEAT

(DEFROST)

FROZENROLLS/MUFFINS

BONE-INPOULTRY

FRESHROLLS/MUFFINS

BONELESSPOULTRY

CHICKENBREAST

0

R - 520LKR-520LW


1. Foilpatterncheckandrepairs. 1) Disconnectthepowersupplycord,andthenremoveoutercase.

) Openthedoorandblockitopen.3) Dischargehighvoltagecapacitor.4) Followthetroubleshootingguidegivenbelowforrepair.

STEPS OCCURRENCE CAUSEORCORRECTION 1 Onlypatternat"a"isbroken. *InsertjumperwireJ1andsolder.

Patternat"a"and"b"arebroken. *InsertthecoilRCILF003YAZZbetween"c"and"d".

5) Make a visual inspection of the varistor.Checkforburneddamageandexaminethetransformerwithatesterforthepresenceoflayershort-circuit(checktheprimarycoilresistancewhichisapproximately563ý±10%).Ifanyabnormalconditionisdetected,replacethecontrolunitassembly.

6) Reconnect all leads removed fromcomponentsduringtesting.

7) Re-installtheoutercase(cabinet).8) Reconnectthepowersupplycordafterthe

outercaseisinstalled.9) Runtheovenandcheckallfunctions.

L FOIL PATTERN ON THE PRINTED WIRING BOARD TESTToprotecttheelectroniccircuits,thismodelisprovidedwithafinefoilpatternaddedtotheprimaryonthePWB,thisfoilpatternactsasafuse.

RY

2

VRS1

L1

J1

a

bc d

. Followthetroubleshootingguidegivenbelow,ifindicatordoesnotlightupafterabovecheckandrepairsarefinished.1) Disconnectthepowersupplycord,andthenremoveoutercase.) Openthedoorandblockitopen.3) Dischargehighvoltagecapacitor.4) Disconnecttheleadstotheprimaryofthepowertransformer.5) Ensure that these leads remain isolated fromothercomponentsandovenchassisbyusing

insulationtape.6) Afterthatprocedure,re-connectthepowersupplycord.7) Followthetroubleshootingguidegivenbelowforrepair.

STEPS OCCURRENCE CAUSEORCORRECTION

TheratedACvoltageisnotpresentbetween 1 thenormalopenterminaloftherelayRY1and Checksupplyvoltageandovenpowercord. thenormalopenterminaloftherelayRY.

TheratedACvoltageispresentatprimaryside Lowvoltagetransformerorsecondarycircuitdefective. oflowvoltagetransformer. Checkandreplacecontrolunitassembly.

8) Disconnectthepowersupplycord,andthenremoveoutercase. 9) Openthedoorandblockitopen. 10) Dischargehighvoltagecapacitor. 11) Reconnectallleadsremovedfromcomponentsduringtesting. 1) Re-installtheoutercase(cabinet). 13) Reconnectthepowersupplycordaftertheoutercaseisinstalled. 14) Runtheovenandcheckallfunctions.(5) Theovenwilloperateforthefirst16seconds,withoutgeneratingmicrowaveenergy.

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R - 520LKR-520LW

WARNING :Theovenshouldbefullyassembledbeforefollowingprocedure.(1) Theovenshouldbepluggedinatleasttwominutesbeforesensorcooking.() Roomtemperatureshouldnotexceed95½F(35½C).(3) Theunitshouldnotbeinstalledinanyareawhereheatandsteamaregenerated.Theunitshould

notbe installed, forexample,next toaconventionalsurfaceunit.Refer to the“INSTALLATIONINSTRUCTIONS”oftheoperationmanual.

(4) Exhaustventsareprovidedonthebackoftheunitforpropercoolingandairflowinthecavity.Topermitadequateventilation,besuretoinstallsoasnottoblockthesevents.Thereshouldbesomespaceforaircirculation.

(5) Besuretheexteriorof thecookingcontainerandthe interiorof theovenaredry.Wipeoffanymoisturewithadryclothorpapertowel.

(6) TheSensorworkswithfoodatnormalstoragetemperature.Forexample,chickenpieceswouldbeatrefrigeratortemperatureandcannedsoupatroomtemperature.

(7) AvoidusingaerosolspraysorcleaningsolventsneartheovenwhileusingSensorsettings.Thesensorwilldetectthevaporgivenofbythesprayandturnoffbeforefoodisproperlycooked.

(8) Ifthesensorhasnotdetectedthevaporofthefood,ERRORwillappearandtheovenwillshutoff.

WaterloadcookingtestWARNING :Theovenshouldbefullyassembledbeforefollowingprocedure.Makesuretheovenhasbeenpluggedinatleasttwominutesbeforecheckingsensorcookoperation.Thecabinetshouldbeinstalledandscrewstightened.(1) Fillapproximately00milliliters(7.oz)oftapwaterina1000millilitermeasuringcup.() Placethecontaineronthecenteroftrayintheovencavity.(3) Openthedoor.(4) TouchtheTIMER/CLOCKonceandthePOWERLEVELpadtwice.Closethedoorandtouchthe

STARTpadonce.Openthedoorandtouchthenumberpads1onceandthenumberpad4once.ClosethedoorandtouchtheSTARTpad.Now,theovenisinthesensorcookingcondition,and"AH0","SENSOR"and"COOK"willappearinthedisplay.

N AH SENSOR TEST Checking the initial sensor cooking condition

(5) Theovenwilloperateforthefirst16seconds,withoutgeneratingmicrowaveenergy.NOTE:ERRORwillappearifthedoorisopenedorSTOP/CLEARpadistouchedduringfirststageof

sensorcooking.(6) Afterapproximately16seconds,microwaveenergyisproduced.IfERRORisdisplayedortheovendoesnotturnoff,replacetheAHsensororcheckthecontrolunit,refertoexplanationbelow.Iftheovenstopsafter5minutesandERRORisdisplayed,theAHsensorisnormal.CheckotherpartsexcepttheAHsensor.

TESTING METHOD FOR AH SENSOR AND/OR CONTROL UNIT

Todetermineifthesensorisdefective,thesimplestmethodistoreplaceitwithanewreplacementsensor.(1) Disconnectthepowersupplycord,andthenremoveoutercase.() Openthedoorandblockitopen.(3) Dischargehighvoltagecapacitor.(4) RemovetheAHsensor.(5) InstallthenewAHsensor.(6) Reconnectallleadsremovedfromcomponentsduringtesting.(7) Re-installtheoutercase(cabinet).(8) Reconnectthepowersupplycordaftertheoutercaseisinstalled.(9) Reconnecttheoventothepowersupplyandcheckthesensorcookoperationasfollows:

9-1.Fillapproximately00milliliters(7.oz)oftapwaterina1000millilitermeasuringcup.9-.Placethecontaineronthecenteroftrayintheovencavity.9-3.Openthedoor.9-4.TouchtheTIMER/CLOCKpadonceandthePOWERLEVELpadtwice.Closethedoorand

touchtheSTARTpadonce.Openthedoorandtouchthenumberpads1onceandthenumberpad4.ClosethedoorandthetouchtheSTARTpad.

9-5.ThecontrolpanelisinautomaticSensoroperation.

R - 520LKR-520LW

Ifnewsensordosenotoperateproperly,theproblemiswiththecontrolunit,andrefertoexplanationbelow.

CHECKING CONTROL UNIT

(1) Disconnectthepowersupplycord,andthenremoveoutercase.() Openthedoorandblockitopen.(3) Dischargehighvoltagecapacitor.(4) Disconnectthesensorconnectorthatismountedtocontrolpanel.(5) Thenconnectthedummyresistorcircuit(seefig.)tothesensorconnectorofcontrolpanel.(6) Disconnecttheleadstotheprimaryofthepowertransformer.(7) Ensurethattheseleadsremainisolatedfromothercomponentsandovenchassisbyusinginsulationtape.(8) Afterthatprocedure,re-connectthepowersupplycord.(9) Checkthesensorcookoperationproceedasfollows:

9-1.Openthedoor.TouchtheTIMER/CLOCKpadonceandthePOWERLEVELpadtwice.ClosethedoorandtouchtheSTARTpadonce.Openthedoorandtouchthenumberpads1onceandthenumberpad4.ClosethedoorandthetouchtheSTARTpad.

9-.Thecontrolpanelisinthesensorcookingoperation.9-3.Afterapproximately5seconds,pushplungerofselectswitchformorethan3seconds.Thisconditionissameas

judgementbyAHsensor.9-4.Afterapproximately3seconds,thedisplayshows“XX.XX“whichisthetimefordetectingmoisture. Iftheaboveisnotthecase,thecontrolunitisprobablydefective. Iftheaboveisproper,theAHsensorisprobablydefective.

(10)Disconnectthepowersupplycord,andthenremoveoutercase.(11)Openthedoorandblockitopen.(1)Dischargehighvoltagecapacitor.(13)Disconnectthedummyresistorcircuitfromthesensorconnectorofcontrolpanel.(14)Carryoutnecessaryrepair.(15)Reconnectallleadsremovedfromcomponentsduringtestingandrepairing.(16)Re-installtheoutercase(cabinet).(17)Reconnectthepowersupplycordaftertheoutercaseis installed.Runtheovenandcheckall

functions.(18)Carryout"Waterloadcookingtest"againandensurethattheovenworksproperly.

R1, R2 : 22Ω ± 1% 1/2W R3 : 4.3Ω ± 5% 1/4W R4 : 1MΩ ± 5% 1/4W

Sensor Dummy Resistor Circuit

Plunger

NC

NO

COM

COM NO

NCR3 R4

R1

R2

1

2

3

F-1

F-2

F-3

To connector (F)on Control Unit.

CONNECTOR

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3) Power Source Circuit Thiscircuitgeneratesvoltagesnecessaryinthecontrol

unitfromtheAClinevoltage. Inaddition,thesynchronizingsignalisavailableinorder

tocomposeabasicstandardtimeintheclockcircuit.

Symbol Voltage Application

VSS -5V LSI(IC1)

4) Relay Circuit A circuit todrive themagnetron, fanmotor, turntable

motorandlighttheovenlamp.

5) Buzzer Circuit The buzzer is responsive to signals from the LSI to

emitaudiblesounds(keytouchsoundandcompletionsound).

6) Synchronizing Signal Circuit Thepowersourcesynchronizingsignalisavailablein

order to composeabasic standard time in the clockcircuit. It accompanies a very small error because itworksoncommercialfrequency.

7) Door Sensing Switch Aswitchto“tell”theLSIifthedoorisopenorclosed.

8) Back Light Circuit Acircuit todrive theback light (Lightemittingdiodes

LD1-LD4).

9) Night Light Circuit Acircuittodrivethelightemittingdiode(LD10).

10) Absolute Humidity Sensor Circuit Thiscircuitdetectsmoistureofthecookingfoodto allowitsautomaticcooking.

TOUCH CONTROL PANEL ASSEMBLY

OUTLINEOFTOUCHCONTROLPANEL

Thetouchcontrolsectionconsistsofthefollowingunits.

(1)KeyUnit()ControlUnit(TheControlUnitconsistsofPowerUnitand LSIUnit).

Theprincipalfunctionsoftheseunitsandthesignalscom-municatedamongthemareexplainedbelow.

Key Unit Thekeyunitiscomposedofamatrix,signalsgeneratedintheLSIaresenttothekeyunitthroughP0-P7.Whenakeypadistouched,asignaliscompletedthroughthekeyunitandpassedbacktotheLSIthroughP70,P71,P41,P45,P47andAN3toperformthefunctionthatwasrequested.

Control UnitControlunitconsistsofLSI,resetcircuit,indicatorcircuit,powersourcecircuit,relaycircuit,buzzercircuit,synchroniz-ingsignalcircuitandbacklightcircuit.

1) Reset Circuit ThiscircuitgeneratesasignalwhichresetstheLSIto

theinitialstatewhenpowerissupplied.

2) Indicator Circuit This circuit consists of segments and 3 common

electrodesusingaLiquidCrystalDisplay.

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Maximumoutput

70%ofmaximumoutput

H:GND

L:-5V

H:GND

L:-5V

ON

ON

OFF

OFF OFF

4sec.

8sec.

1- VL-VL1 IN Power source voltage input terminal. StandardvoltageforLCD.

3-6 AN7-AN4 IN Terminal to change cooking input according to the Model. ByusingtheA/DconvertercontainedintheLSI,DCvoltageinaccordancewiththe

Modelinoperationisappliedtosetupitscookingconstant.

7 AN3 IN Signal coming from touch key. WheneitherG13lineonkeymatrixistouched,acorrespondingsignaloutofP0-P7

willbeinputintoAN3.Whennokeyistouched,thesignalisheldat“H”level.

8 AN IN To input signal which communicates the door open/close information to LSI. Doorclose"H"levelsignal(0V).DoorOpen"L"level(-5V).

9 AN1 IN Terminalnotused.

10 AN0 IN Terminalnotused.

11-13 P57-P55 OUT Terminalnotused.

14 CNTR0 OUT Signal to sound buzzer (2.0 kHz). A:keytouchsound.

B:Completionsound.

15 P53 OUT Usedforinitialbalancingofthebridgecircuit(absolutehumiditysensor).

16 P5 OUT Oven lamp, fan motor and turntable motor driving signal Toturnonandoffshutoffrelay(RY1).The

squarewaveformvoltageisdeliveredtotheRY1drivingcircuitandRYcontrolcircuit.

17 P51 OUT Usedforinitialbalancingofthebridgecircuit(absolutehumiditysensor).

18 P50 OUT Magnetron high-voltage circuit driving signal. Toturnonandoffthecookrelay(RY).The

signalsholds“L”levelduringmicrowavecook-ingand“H”levelwhilenotcooking.Inothercookingmodes(variablecooking)thesignalturns to“H” leveland“L” level inrepetitionaccordingtothepowerlevel.

19 P47 IN Signal similar to AN3. WheneitherG13lineonkeymatrixistouched,acorrespondingsignalwillbeinputinto

P46.

0 P46 OUT Terminalnotused.


P45.

-3 P44-P43 OUT Terminalnotused.

4 INT0 IN Signal synchronized with commercial power source frequency. ThisisthebasictimingfortimeprocessingofLSI.

DESCRIPTION OF LSILSITheI/OsignaloftheLSIisdetailedinthefollowingtable.

Pin No. Signal I/O Description

A

B

0.1sec.

.0sec.

H:GND

L:-5V

H:GND

L:-5V

16.7msec.

Duringcooking

H:GND

L:-5V

16.7msec.

H:GND

L:-5V

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P41.

6 P40 IN ConnectedtoGNDthroughthepull-downresistor.

7 RESET IN Auto clear terminal. SignalisinputtoresettheLSItotheinitialstatewhenpowerisapplied.


P71.

9 P70 IN Signal similar to ANI3. WheneitherG9lineonkeymatrixistouched,acorrespondingsignalwillbeinputinto

P70.

30 XIN IN Internal clock oscillation frequency control input setting. Theinternalclockfrequencyissetbyinsertingtheceramicfilteroscillationcircuitwith

respecttoXOUTterminal.

31 XOUT OUT Internal clock oscillation output. OutputtocontroloscillationinputtoXIN.

3 VSS IN Power source voltage : -5.0V. ThepowersourcevoltagetothedriveLSIisinputtoVSSterminal.

33 P7 OUT Key strobe signal. Signalappliedtotouch-keysection.ApulsesignalisinputtoP70,P71,P41,P45,P47

andAN3terminalwhileoneofG8linekeysonkeymatrixistouched.









38 P OUT Key strobe signal. Signalappliedtotouch-keysection.ApulsesignalisinputtoP70,P71,P41,P45,P47



andAN3terminalwhileoneofGlinekeysonkeymatrixistouched.



41 P17 OUT Back light signal.(Lightemittingdiodes)drivingsignal

4-46 P16-P1 OUT Terminalnotused.

47-50 SEG5-SEG OUT Terminalnotused.

51-7 SEG1-SEG0 OUT Segment data signal.


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ConnectedtoLCD.

Therelationbetweensignalsareasfollows: LSIsignal(PinNo.) LCD(PinNo.) LSIsignal(PinNo.) LCD(PinNo.) SEG0(7).................................. SEG0 SEG11(61)................................SEG11 SEG1(71).................................. SEG1 SEG1(60)................................SEG1 SEG(70).................................. SEG SEG13(59)................................SEG13 SEG3(69).................................. SEG3 SEG14(58)................................SEG14 SEG4(68).................................. SEG4 SEG15(57)................................SEG15 SEG5(67).................................. SEG5 SEG16(56)................................SEG16 SEG6(66).................................. SEG6 SEG17(55)................................SEG17 SEG7(65).................................. SEG7 SEG18(54)................................SEG18 SEG8(64).................................. SEG8 SEG19(53)................................SEG19 SEG9(63).................................. SEG9 SEG0(5)................................SEG0 SEG10(6)................................. SEG10 SEG1(51)................................SEG1

73 VCC IN Powersourcevoltage:GND(0V).

74 VREF IN A/D converter power source voltage : GND(0V). ThepowersourcevoltagetodrivetheA/Dconverter.ConnectedtoGND.

75 AVSS IN A/D converter power source voltage : -5.0V. ThepowersourcevoltagetodrivetheA/Dconverter.

76 COM3 OUT Terminalnotused.

77 COM OUT Common data signal. ConnectedtoLCDsignalCOM1.

78 COM1 OUT Common data signal. ConnectedtoLCDsignalCOM.

79 COM0 OUT Common data signal. ConnectedtoLCDsignalCOM3.

80 VL3 IN Power source voltage input terminal. StandardvoltageforLCD.ConnectedtoGND.


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(1) Structure of Absolute Humidity Sensor Theabsolutehumiditysensorincludestwothermistors

asshownintheillustration.Onethermistorishousedintheclosedvesselfilledwithdryairwhileanotherintheopenvessel.Eachsensorisprovidedwiththeprotectivecovermadeofmetalmesh tobeprotected from theexternalairflow.

(2) Operational Principle of Absolute Humidity Sensor

The figure below shows the basic structure of anabsolutehumiditysensor.Abridgecircuitisformedbytwothermistorsandtworesistors(R1andR).

Theoutputofthebridgecircuitistobeamplifiedbytheoperationalamplifier.

Eachthermistorissuppliedwithacurrenttokeepitheatedatabout150½C(30½F),theresultantheatisdissipatedintheairandifthetwothermistorsareplacedindifferenthumidityconditionstheyshowdifferentdegreesofheatconductivityleadingtoapotentialdifferencebetweenthemcausinganoutputvoltagefromthebridgecircuit,the intensity of which is increased as the absolutehumidityoftheairincreases.Sincetheoutputisveryminute,itisamplifiedbytheoperationalamplifier.

(3) Detector Circuit of Absolute Humidity Sensor Circuit

ThisdetectorcircuitisusedtodetecttheoutputvoltageoftheabsolutehumiditycircuittoallowtheLSItocontrolsensor cooking of the unit. When the unit is set inthesensorcookingmode,16secondsclearingcycleoccursthanthedetectorcircuitstartstofunctionandtheLSIobservestheinitialvoltageavailableatitsAN1terminal.

Withthisvoltagegiven,theswitchesSW1toSW5intheLSIareturnedoninsuchawayastochangetheresistancevaluesinparallelwithR98~R10.ChangingtheresistancevaluesresultsinthatthereisthesamepotentialatbothF-3terminaloftheabsolutehumiditysensorandAN0terminaloftheLSI.ThevoltageofAN1terminalwillindicateabout-.5V.Thisinitialbalancingissetupabout16secondsaftertheunitisputintheSensorCookingmode.Asthesensorcookingproceeds,

ABSOLUTE HUMIDITY SENSOR CIRCUIT

thefoodisheatedtogeneratemoisturebywhichtheresistancebalanceofthebridgecircuitisdeviatedtoincreasethevoltageavailableatAN1terminalof theLSI.

Then the LSI observes that voltage at AN1 terminaland compares it with its initial value, and when thecomparison rate reaches the preset value (fixed foreachmenutobecooked),theLSIcausestheunittostopsensorcooking;thereafter,theunitgoesinthenextoperationautomatically.

WhentheLSIstartstodetecttheinitialvoltageatAN1terminal16secondsaftertheunithasbeenputintheSensorCookingmode,ifitisnotpossibletobalancethebridgecircuitduetodisconnectionoftheabsolutehumiditysensor,ERRORwillappearonthedisplayandthecookingisstopped.

ventilation opening for sensing Sensing part(Open vessel)

Sensing part(Closed vessel)

Thermistors

C

S

R3

R1

R2

+

Operationalamplifier

Outputvoltage

S : Thermistoropen vessel

C : Thermistorclosed vessel

2Absolute humidity (g/m )

Out

putv

olta

ge

Absolute humidity vs,output voltage characteristic

SW1

SW2

SW3

SW4

SW5

P57

P56

P55

P51

P53

LSI(IC1)

AN0

AN1

620k

300k

150k

75k

37.4k

11

17

15

10

9

13

12

47k

47k

10k1 2 3 4

8 7 6 5

0.01

uF

0.01

5uF

0.01

uF

VA : -15V VA : -15V

R90

C90

C91

C93

C92

S

F-2 1.8k IC2

F-1

F-3C

3.57k

3.32k

VC : -5V

0.1

uF

C. Thermistor inclosed vessel

S. Thermistor inopen vessel

R98

R99

R96

R91

360kR93R92

R94 R95

D90

R100

R101

R102

R97

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1. Precautions for Handling Electronic Components ThisunitusesCMOSLSIintheintegralpartofthecircuits.

Whenhandling theseparts, the followingprecautionsshouldbestrictlyfollowed.CMOSLSIhaveextremelyhigh impedanceat its inputandoutput terminals.Forthis reason, it iseasily influencedby thesurroundinghighvoltagepowersource,staticelectricitycharge inclothes,etc.andsometimesitisnotfullyprotectedbythebuilt-inprotectioncircuit.

InordertoprotectCMOSLSI.1) Whenstoringandtransporting,thoroughlywrapthem

inaluminiumfoil.AlsowrapallPWboardscontainingtheminaluminiumfoil.

) When soldering, ground the technician as shown inthefigureandusegroundedsoldering ironandwork

TOUCH CONTROL PANEL SERVICING

6) Runtheovenandcheckallfunctions.A. Onsomemodels,thepowersupplycordbetweenthe

touchcontrolpanelandtheovenitselfissoshortthatthetwocan’tbeseparated.Forthosemodels,checkandrepairallthecontrols(sensor-relatedonesincluded)ofthetouchcontrolpanelwhilekeeping itconnectedtotheoven.

B. Onsomemodels,thepowersupplycordbetweenthetouchcontrolpanelandtheovenproperislongenoughthattheymaybeseparatedfromeachother.Forthosemodels,itispossibletocheckandrepairthecontrolsofthetouchcontrolpanelwhilekeepingitapartfromtheovenproper;inthiscaseyoumustshortbothendsofthedoorsensingswitch(onPWB)ofthetouchcontrolpanelwithajumper,whichactivatesanoperationalstatethatisequivalenttotheovendoorbeingclosed.Asforthesensor-relatedcontrolsofthetouchcontrolpanel,checking them is possible if dummy resistor(s) withresistanceequaltothatofthecontrolsareused.

(2) Servicing the touch control panel with power supply from an external power source:

Disconnectthetouchcontrolpanelcompletelyfromtheovenproper,andshortbothendsofthedoorsensingswitch (on PWB) of the touch control panel, whichactivatesanoperationalstatethatisequivalenttotheoven door being closed. Connect an external powersourcetothepowerinputterminalofthetouchcontrolpanel,thenitispossibletocheckandrepairthecontrolsof thetouchcontrolpanel it isalsopossibletocheckthesensor-relatedcontrolsofthetouchcontrolpanelbyusingthedummyresistor(s).

3. Servicing Tools Tools required to service the touch control panel

assembly.1)Solderingiron:30W (It is recommended to use a soldering iron with a

groundingterminal.))Oscilloscope:Singlebeam,frequencyrange:DC-10MHz

typeormoreadvancedmodel.3)Others:Handtools

4. Other Precautions1) Beforeturningonthepowersourceofthecontrolunit,

removethealuminiumfoilappliedforpreventingstaticelectricity.

) Connect theconnectorsof thekeyunit to thecontrolunitbeingsurethattheleadwiresarenottwisted.

3)Afteraluminiumfoilisremoved,becarefulthatabnormalvoltageduetostaticelectricityetc.isnotappliedtotheinputoroutputterminals.

4)Attachconnectors,electrolyticcapacitors,etc.toPWB,makingsurethatallconnectionsaretight.

table.

2. Servicing of Touch Control Panel Wedescribetheprocedurestopermitservicingofthe

touch control panel of the microwave oven and theprecautionsyoumusttakewhendoingso.Toperformtheservicing,powertothetouchcontrolpanelisavailableeitherfromthepowerlineoftheovenitselforfromanexternalpowersource.

(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 AND PRESENTS A HAZARD.

Therefore,beforecheckingtheperformanceofthetouchcontrolpanel,1) Disconnectthepowersupplycord,andthenremove

outercase.) Openthedoorandblockitopen.3) Dischargehighvoltagecapacitor.4) Disconnect the leads to the primary of the power

transformer.5) Ensurethattheseleadsremainisolatedfromother

componentsandovenchassisbyusing insulationtape.

6) After thatprocedure, re-connect thepowersupplycord.

After checking the performance of the touch controlpanel,

1) Disconnectthepowersupplycord.) Openthedoorandblockitopen.3) Re-connect the leads to theprimaryof thepower

transformer.4) Re-installtheoutercase(cabinet).5) Re-connect the power supply cord after the outer

caseisinstalled.

approx.1Mohm

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Toremovetheoutercase,proceedasfollows.1.Disconnectthepowersupplycord.. Opentheovendoorandblockitopen.3.Remove the two()screws fromthe lowerportionof

therearcabinetusingaT0HTorxtypeorGTXH0-100screwdriver.

4. Removetheremainingtwo()screwsfromrear.5.Slidetheentireoutercasebackoutabout1inch(3cm)

tofreeitfromretainingclipsonthecavityfaceplate.6.Liftentireoutercasefromtheunit.

mayresultinsevere,possiblyfatal,electricshock.(Example)HighVoltage Capacitor, PowerTransformer, Magnetron, HighVoltage Rectifier Assembly, HighVoltage Harnessetc..

WARNING: To Avoid possible exposure to microwave energy, please follow the instructions below

before operating the oven.

WARNING AGAINST HIGH VOLTAGE:Microwaveovenscontaincircuitrycapableofproducingveryhighvoltageandcurrent.Contactwiththefollowingparts

OUTER CASE REMOVAL

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE

To prevent an electric shock, take the following pre-cautions:1. Beforewiring:

1) Disconnectthepowersupplycord.) Openthedoorblockitopen.3) Wait 60seconds, thendischarge thehighvoltage

capacitor.. Don’tletthewireleadstouchtothefollowingparts:

1) Highvoltageparts: Magnetron,Highvoltagetransformer,Highvoltage

capacitorandHighvoltagerectifierassembly.) Hotparts: Ovenlamp,Magnetron,Highvoltagetransformerand

Ovencavity.

WARNING FOR WIRING

1. Disconnectthepowersupplycord.. Makesure thatadefinite”click”canbeheardwhen

themicrowaveovendoorisunlatched.(Holdthedoorinaclosedpositionwithonehand,thenpushthedooropenbuttonwiththeother,thiscausesthelatchleadstorise,itisthenpossibletoheara“click’asthedoorswitchesoperate.)

3. Visuallycheckthedoorandcavityfaceplatefordamage(dents,cracks,signsofarcingetc.).

Carry out any remedial work that is necessary beforeoperatingtheoven.Donotoperatetheovenifanyofthefollowingconditionsexist:

1. Doordoesnotclosefirmly.. Doorhinge,supportorlatchhookisdamaged.3. Thedoorgasketorsealisdamaged.4. Thedoorisbentorwarped.5. There are defective parts in the door interlock

system.6. Therearedefectivepartsinthemicrowavegenerating

andtransmissionassembly.7. Thereisvisibledamagetotheoven.

Donotoperatetheoven:1. WithouttheRFgasket(Magnetron).. Ifthewaveguideorovencavityarenotintact.3. Ifthedoorisnotclosed.4. Iftheoutercase(cabinet)isnotfitted.

3) Sharpedge: Bottom plate, Oven cavity, Waveguide flange,

Chassissupportandothermetallicplate.4) Movableparts(topreventafault): Fanblade,Fanmotor,Switch,Switchlever,Open

button.3. Donotcatchthewireleadsintheoutercasecabinet.4. Insertthepositivelockconnectoruntilitspinislocked

andmakesurethat thewire leadsdonot comeoffevenifthewireleadsarepulled.

5. Topreventanerror function,connect thewire leadscorrectly,referringtothePictorialDiagram.

Pleasereferto‘OVENPARTS,CABINETPARTS,CONTROLPANELPARTS,DOORPARTS’,whencarryingoutanyofthefollowingremovalprocedures:

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POWER TRANSFORMER REMOVALRe-install1. Rest transformeron thebottomplatewith itsprimary

terminalstowardtheovenfaceplate.. Securetransformerwithfourscrewstobottomplate.3. Re-connect wire leads (primary and high voltage) to

power transformer and filament leads of transformerto magnetron and high voltage capacitor. Refer to"PICTORIALDIAGRAM"onpage30.

4. Re-installoutercaseandcheckthatovenisoperatingproperly.

1. Disconnectthepowersupplycordandthenremoveoutercase.

. Opentheovendoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Disconnectwireleads(primaryandhighvoltage)from

power transformer and the filament leads from themagnetronandcapacitorterminals.

5. Removetwo()screwsholdingtransformertobottomplate.

6. Removetransformerfrombottomplate.

CAUTION: 1. DISCONNECTOVENFROMPOWERSUP-PLYBEFOREREMOVINGOUTERCASE.

. DISCHARGE THE HIGH VOLTAGE CA-PACITORBEFORETOUCHINGANYOVENCOMPONENTSORWIRING.

NOTE: When replacing the outer case, the 2 special Torx screws must be reinstalled in the same locations.

HIGH VOLTAGE RECTIFIER AND HIGH VOLTAGE CAPACITOR REMOVAL

1.Disconnectthepowersupplycordandthenremoveoutercase.

. Openthedoorandblockitopen.3.Dischargehighvoltagecapacitor.4.DisconnectthehighvoltagewireAfromthehighvoltage

capacitor.5.Disconnectthehighvoltagewireofhighvoltagerectifier

assemblyfromthemagnetron.6.Disconnectthefilamentlead(shortone)ofthepower

transformerfromthehighvoltagecapacitor.

7.Removeone(1)screwholdingcapacitorholderwiththehighvoltagerectifiertothebaseplate.

8.Disconnectrectifierterminalfromcapacitor. Highvoltagerectifierassemblyisnowfree.9.Removecapacitorholder.Capacitorisnowfree.

CAUTION:WHEN REPLACING HIGH VOLTAGE REC-TIFIER AND HIGH VOLTAGE CAPACITOR,GROUND SIDE TERMINAL OF THE HIGHVOLTAGERECTIFIERMUSTBESECUREDFIRMLYWITHAGROUNDINGSCREW.

MAGNETRON REMOVALRemoval1.Disconnectthepowersupplycordandthenremoveouter

case.. Openthedoorandblockitopen.3.Dischargehighvoltagecapacitor.4.Disconnectwireleadsfrommagnetron.5.Removethetwo()screwsholdingthechassissupport

tothemagnetronandtheovencavityfrontflange.6.Slide the magnetron duct slightly so that the two ()

screwsatlefthandsideofthemagnetronappear.7.Carefullyremovethefour(4)screwsholdingmagnetron

towaveguideflange.8. Removethemagnetronwithcaresothatthemagnetron

antenna is not hit by any metal object around theantenna.

9.Now,themagnetronisfree.

Re-install1. Re-installthemagnetrontowaveguideflangewithcare

topreventdamagetothemagnetronantenna.. Securethemagnetronwiththefour(4)screws.3. Holdthechassissupporttotheovencavityfrontplate

andthemagnetronwiththetwo()screws.4.Reconnect thewire leads to themagnetron.Refer to

"PICTORIALDIAGRAM"onpage30.5. Re-installoutercaseandcheckthattheovenisoperating

properly.CAUTION: WHENREPLACINGMAGNETRON,BESURE

THER.F.GASKETISINPLACEANDMOUNT-INGSCREWSARETIGHTENEDSECURELY

Special screw

Screw Driver(Type: TORX T20 H orGTXH20-100)

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R - 520LKR-520LW

POSITIVE LOCK® CONNECTOR (NO-CASE TYPE) REMOVAL

Figure C-2. Positive lock® connector

1. Disconnect the power supply cord, and then removeoutercase.

. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Pushtheleverofpositivelock®connector.5. Pulldownonthepositivelock®connector.

CAUTION: WHENCONNECTINGTHEPOSITIVELOCK®CONNECTORSTOTHETERMINALS,CON-NECTTHEPOSITIVELOCK®SOTHATTHELEVERFACESYOU.

1.Disconnect the power supply cord and remove outercase.

. Openthedoorandblockitopen.3.Dischargehighvoltagecapacitor.4. Removetheovenlampfromtheovenlampsocket.5.Pullthewireleadsfromtheovenlampsocketbypushing

theterminalholeoftheovenlampsocketwiththesmallflattypescrewdriver.

6.Removetheovenlampsocketfromthemagnetronductbyturningthesocketcounterclockwise.

7. Removetheovenlampfromthesocketbyturningtheovenlamp.

OVEN LAMP AND LAMP SOCKET REMOVAL

8. Now, the oven lamp and the oven lamp socket are

CONTROL PANEL ASSEMBLY REMOVAL

1. Disconnectthepowersupplycordandthenremoveoutercase.

. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Disconnectthewireleadsfrompanelcomponents.5. Remove the one (1) screw holding the control panel

assemblytotheovencavityfrontplate.6. Slidethecontrolpanelassemblyupwardandremove

it.7. Now,individualcomponentscanberemoved.

NOTE:1. Beforeattachinganewkeyunit,wipeoffremainingadhesive on the control panel frame surfacescompletelywithasoftclothsoakedinalcohol.

.Whenattachingthekeyunittothecontrolpanelframe,adjusttheupperedgeandrightedgeofthekeyunittothecorrectpositionofcontrolpanelframe.

3.Placethekeyunitfirmlytothecontrolpanelframebyrubbingwithsoftclothnottoscratch.

Removal1. Disconnectthepowersupplycordandthenremoveoutercase.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Removethecontrolpanelassembly,referringtochapterofCONTROLPANELASSEMBLYREMOVAL.5. Removethethree(3)screwsholdingthecontrolunittothecontrolpanelframe.Andremovethecontrolunitbyreleasingfrom

tabs.6. Removetherubberconnectorfromthelongslitonthecontrolpanelframe.7. Removethenightlightcover(releasetabsfrombackside).8. Removethegraphicsheetfromthecontrolpanelframe.(*Seespecialnote)9. Removeawaythemembraneswitchfromthecontrolpanelframe.(*Seespecialnote)

Figure C-XXX Graphic Sheet and Membrane Switch Replacement

GRAPHIC SHEET AND MEMBRANE SWITCH REPLACEMENT

Oven lampsocket

Terminal

3

R - 520LKR-520LW

.Remove turntable and turntable support from ovencavity.

3.Laytheovenonit'sbackside.Removetheturntablemotorcoverbysnippingoffthematerialinfourcorners.

4. Wherethecornershavebeensnippedoffbendcornerareasflat.Nosharpedgesmustbeevidentafterremovaloftheturntablemotorcover.

TURNTABLE MOTOR REMOVAL1.Disconnectthepowersupplycord.

5.Disconnectwireleadsfromturntablemotor. (See"Positivelockconnectorremoval")6.Removeone(1)screwholdingturntablemotortooven

cavity.7.Nowtheturntablemotorisfree.8. Afterreplacement,usetheone(1)screwprovidedwith

theTTMKit,toattachtheturntablemotorcover.

Installation1.Removeremainingadhesiveonthecontrolpanelframesurfaceswithasoftclothsoakedinalcohol..MakesurethattheLCDsheetandtheliquidcrystaldisplayisinstalledinposition.3.Removethebackingpaperfromthenewmembraneswitchandribboncable.4.Inserttheribboncableofthemembraneswitchintotheslitofthecontrolpanelframe.5.Adjusttheupperedgeandrightedgeofthemembraneswitchtothesmalldepressiononthesurfaceofthecontrol

panelframe.6.Attachthemembraneswitchtothecontrolpanelframebyrubbingwithasoftclothnottoscratch.7.Removethebackingpaperfromthenewgraphicsheet.8.Adjusttheupperedgeandrightedgeofthegraphicsheettothelargedepressiononthesurfaceofthecontrolpanel

frame.9.Attachthegraphicsheettothecontrolpanelframebyrubbingwithasoftclothnottoscratch.10.Attachtheribboncabletothecontrolpanelframerearside.11.Placetheedgeofthemembraneswitch’sribboncableonthelowerportionoftheliquidcrystaldisplay.1.Inserttherubberconnectorintothelongslitonthecontrolpanelframe.13.Reinstallthecontrolunittothecontrolpanelframewiththethree(3)screws.NOTE:Do not touch the contact surface of the ribbon cable (edge) and the rubber connector with a finger directly not to be oxidized.If display digits are missing or scrambled, remove control unit and make sure that there is not any trash or foreign substance on the contact surface of the rubber connector. Use an adhesive tape to clean the contact surface of the rubber connector. (* Heat gun will soften adhesive.)

Rubber connectorContact surface

Contactsurface

Ribbon cableof membraneswitch

Liquid crystal display

Liquid crystal display

Ribboncable

Graphicsheet

Membraneswitch

LCD sheet

Control panel frame(Rear side)

Control panel frame

Long slitSlit

33

R - 520LKR-520LW

COOLING FAN MOTOR REMOVALREMOVAL1.Disconnectthepowersupplycordandthenremoveouter

case.. Openthedoorandblockitopen.3.Dischargehighvoltagecapacitor.4.Disconnectthewireleadsfromthefanmotor.5.Removethetwo()screwsholdingthefanmotortothe

ovencavitybackplate.6. Removethefanbladefromthefanmotorshaftaccording

tothefollowingprocedure.7. Holdtheedgeoftherotorofthefanmotorbyusinga

pairofgroovejointpliers.CAUTION: * Make sure that no metal pieces 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.

8. Removethefanbladefromtheshaftofthefanmotorbypullingandrotatingthefanbladewithyourhand.

9. Now,thefanbladeandthefanmotorwillbefree.

CAUTION:* Do not reuse the removed fan blade because the

hole (for shaft) may be larger than normal.

INSTALLATION1. Installthefanbladetothefanmotorshaftaccordingto

thefollowingprocedure.. Holdthecenterofthebracketwhichsupportstheshaft

ofthefanmotorontheflattable.3. Applythescrewlocktightintothehole(forshaft)ofthe

fanblade.4. Installthefanbladetotheshaftoffanmotorbypushing

thefanbladewithasmall,lightweight,ballpeenhammerorrubbermallet.

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.5. Installthefanmotortotheovencavitybackplatewith

thetwo()screws.6. Connectthewireleadstothefanmotor,referringtothe

pictorialdiagram.

DOOR SENSING SWITCH/PRIMARY INTERLOCK SWITCH AND MONITOR SWITCH REMOVAL1. Disconnect the power supply cord and remove outer

case.. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.4. Disconnectwireleadsfromtheswitches.5. Removetwo()screwsholdinglatchhooktoovenflange.6. Removelatchhookassemblyfromovenflange.7. Pushoutwardonthetwo()retainingtabsholdingswitch

inplace.

8. Switchisnowfree. Atthistimeswitchleverwillbefree,donotloseit.Re-install1. Re-installeachswitchinitsplace.Theprimaryinterlock/

monitorswitchesareinthelowerpositionandthedoorsensingswitchisintheupperposition.

. Re-connectwireleadstoeachswitch.

Side ViewRear View

34

R - 520LKR-520LW

3. Secure latch hook (with two () mounting screws) toovenflange.

4. Make sure that the monitor switch is operatingproperly

andcheckcontinuityofthemonitorcircuit.Refertochapter"TestProcedure"andAdjustmentprocedure.

DOOR SENSING SWITCH/PRIMARY INTERLOCK SWITCH AND MONITOR SWITCH ADJUSTMENT

1. Disconnect the power supply cord, and then removeoutercase.

. Openthedoorandblockitopen.3. Dischargehighvoltagecapacitor.

Ifthedoorsensingswitch,primaryinterlockswitchandmoni-torswitchdonotoperateproperlyduetoamisadjustment,thefollowingadjustmentshouldbemade.4. Loosenthetwo()screwsholdinglatchhooktotheoven

cavityfrontflange.5. Withdoorclosed,adjustlatchhookbymovingitback

and forth,andupanddown.Inandoutplayofthedoorallowed

bytheupperandlowerpositionofthelatchhookshouldbe lessthan0.5mm.Theverticalpositionof the latchhookshouldbeadjustedsothatthedoorsensingswitchandprimaryinterlockswitchareactivatedwiththedoorclosed.Thehorizontalpositionofthelatchhookshouldbeadjustedsothattheplungerofthemonitorswitchispressedwiththedoorclosed.

6. Securethescrewswithwashersfirmly.7. Checktheoperationofallswitches.Ifeachswitchhas

notactivatedwith thedoorclosed, loosenscrewandadjustthelatchhookposition.

After adjustment, check the following. 1. Inandoutplayofdoorremainslessthan0.5mmwhen

inthelatchedposition.Firstcheckupperpositionoflatchhook,pushingandpullingupperportionofdoortowardtheovenface.Thenchecklowerportionofthelatch

Figure C-3. Latch Switch Adjustments

hook,pushingandpullingupperportionofdoortowardtheovenface.Bothresults(playinthedoor)shouldbelessthan0.5mm.

. Thedoorsensingswitchandprimary interlockswitchinterruptthecircuitbeforethedoorcanbeopened.

3. Monitorswitchcontactsclosewhendoorisopened.4. Re-installoutercaseandcheckformicrowaveleakage

arounddoorwithanapprovedmicrowavesurveymeter.(RefertoMicrowaveMeasurementProcedure.)

DOOR REPLACEMENT

Figure C-4. Door Disassembly

REMOVAL1. Disconnectthepowersupplycord.. Pushtheopenbuttonandopenthedoorslightly.3. Insertaputtyknife(thicknessofabout0.5mm)intothe

gapbetweenthechokecoveranddoorframeasshowninFigureC-4tofreeengagingparts.

4. PrythechokecoverbyinsertingaputtyknifeasshownFigureC-4.

5. Releasechokecoverfromdoorpanel.6. Nowchokecoverisfree.7. Releasetwo()pinsofdoorpanelfromtwo()holesof

upperandlowerovenhingesbyliftingup.8. Now, door panel with door frame is free from oven

Door S ens ingS witch

Monitor S witch

S witch Lever

P rimary InterlockS witch

Latch Heads

Door

Choke Cover

Door Frame

Putty Knife

35

R - 520LKR-520LW

9. Releasethedoorpanelfromtwelve(1)tabsofdoorframe.

10.Removethedoorpanelfromthedoorframe.11.Now,doorpanelwithsealerfilmisfree.1.Tearsealerfilmfromdoorpanel.13.Now,doorpanelisfree.14.Slidelatchheadupwardandremoveitfromdoorframe

with releasing latchspring fromdoor frameand latchhead.

15.Now,latchheadandlatchspringarefree.16.Removedoorscreenfromdoorframe17.Now,doorframeisfree.

RE-INSTALL1. Re-installdoorscreentodoorframe.. Re-installthelatchspringtothelatchhead.Re-install

thelatchspringtothedoorframe.Re-installlatchheadtodoorframe.

3. Re-installdoorpaneltodoorframebyfittingtwelve(1)tabsofdoorframetotwelve(1)holesofdoorpanel.

4. Putsealerfilmondoorpanel.Referto“SealerFilm”abouthowtohandlenewone.

5. Catchtwo()pinsofdoorpanelontwo()holeofupperandlowerovenhinges.

6. Re-installchokecovertodoorpanelbypushing.

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

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

latchholesandthatlatchheadgoesthroughcenteroflatchhole.

. Deviationofdooralignmentfromhorizontallineofcavityfaceplateistobelessthan1.0mm.

3. Door ispositionedwith itsfacepressedtowardcavityfaceplate.

4. Check for microwave leakage around door with anapprovedmicrowavesurveymeter.(RefertoMicrowaveMeasurementProcedure.)

Note: Thedooronamicrowaveovenisdesignedtoactas an electronic seal preventing the leakage ofmicrowave energy from oven cavity during cookcycle.Thisfunctiondoesnotrequirethatdoorbeair-tight,moisture(condensation)-tightorlight-tight.Therefore,occasionalappearanceofmoisture,lightor sensingof gentlewarmairmovement aroundovendoorisnotabnormalanddonotofthemselvesindicatealeakageofmicrowaveenergyfromovencavity.

SEALER FILMInstallation1. Puttheadhesivetapeonthebackingfilmofthesealer

filmasshowninFig.C-6.. Tearthebackingfilmbypullingtheadhesivetape.3. Put the pasted side of the sealer film on the door

panel

Note:

Whencarringoutanyrepairtothedoor,donotbendorwraptheslitchoke(tabsonthedoorpanelassembly)topreventmicrowaveleakage.

36

R - 520LKR-520LW

64 51 2 3

64 51 2 3

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37

R - 520LKR-520LW

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64 51 2 3

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R - 520LKR-520LW

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Figure S-5 . Printed Wiring Board of Power Unit

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39

R - 520LKR-520LW

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

PARTS LISTNote: The parts marked “∆” may cause undue microwave exposure. The parts marked “*” are used in voltage more than 250V. "§"MARK:PARTSDELIVERYSECTION.

∆

ELECTRIC PARTS1- 1 RC-QZB018MRE0 M High voltage capacitor 1 AQ1- 2 FH-DZB013MRY0 M High voltage rectifier assembly 1 AM1- 3 RLMPTA087WRZZ M Oven lamp/socket 1 AE1- 4 RMOTEA433WRZZ M Fan motor 1 AL1- 5 FFS-BA016/KIT M Monitor switch (V-16G-2C25)and fuse assembly (20A 250V AC) 1 AF1- 6 QSW-MA085WRE0 M Primary interlock switch and door sensing switch (V-5230Q) 2 AE1- 7 QFS-TA014WRE0 M Cavity temperature fuse 150OC 1 AF1- 8 RV-MZA293WRE0 M Magnetron 1 BC1- 9 RMOTDA264/KIT M Turntable motor 1 AL1-10 RTRN-B088MRE0 M Power transformer 1 BA1-11 FACCDB003MRE0 M Power supply cord 1 AM1-12 QFS-TA013WRE0 M Magnetron temperature fuse 1 AE1-13 FPWBFA380WRKZ M Noise filter unit 1 AM1-14 FDTCTA198WRK0 M AH sensor 1 AN

CABINET PARTS2- 1 GDAI-B061MRP0 M Base plate 1 AS2- 2 GLEGPB004MRF0 M Foot 4 AB2- 3 GCABUB096MRP0 M Outer case cabinet (R-520LK) 1 AV2- 3 GCABUB089MRP0 M Outer case cabinet (R-520LW) 1 AW

CONTROL PANEL PARTS 3- 1 GPNLCB090MRK0 M Control unit assy 1 BB 3- 2 HPNLFB024MRF0 M Control panel (R-520LK) 1 AS 3- 2 HPNLFB025MRF0 M Control panel (R-520Lw) 1 AS 3- 3 FUNTKB461/KIT M Key sheet assy (R-520LK) 1 AL 3- 3 FUNTKB469/KIT M Key sheet assy (R-520LW) 1 AL 3- 4 JBTN-B201MRF0 M Open button assy (R-520LK) 1 AL 3- 4 JBTN-B203MRF0 M Open button assy (R-520LW) 1 AP 3- 5 MSPRCA045WRE0 M Open button spring 1 AA 3- 6 XEPSD30P08XS0 M Screw; 3mm x 6mm 5 AB 3- 7 QCNC-A020WRZZ M Rubber connector 1 AC 3- 8 PSHEPB037WREZ M LED sheet 1 AG 3- 9 RLCDSA116DRZZ M LCD 1 AE 3-10 LANGQB060MRP0 M PWB support angle 1 AE 3-11 HPNLCB179MRF0 M Key fixing mold 1 AL

OVEN PARTS4- 1 LBNDKB007MRP0 M H.V. Capacitor band 1 AB4- 2 LANGTB062MRP0 M Chassis support 1 AD4- 3 PHOK-B018MRF0 M Latch hook 1 AF4- 4 MLEVPB016MRF0 M Switch lever 1 AD4- 5 PDUC-B125MRF0A M Magnetron duct 1 AE4- 6 NFANPB006MRE0 M Fan blade 1 AC4- 7 PDUC-B088MRF0 M Fan duct 1 AC4- 8 ------------- M Oven cavity (Not a replaceable part) 1 --4- 9 PCOVPB085MRP0 M Waveguide cover 1 AH4-10 PPACGB014MRF0 M Turntable motor packing 1 AA4-11 PCUSUB080MRP0 M Cushion 1 AC4-12 LANGQB025MRP0 M Noise unit angle 1 AE4-13 PDUC-B106MRP0 M Sensor duct 1 AG

DOOR PARTS5 -1 GWAKPB226MRR0 M Door frame (R-520LK) 1 AQ5 -1 GWAKPB228MRR0 M Door frame (R-520LW) 1 AQ5 -2 LSTPPB021MRF0 M Latch head 1 AD5 -3 MSPRTA046WRE0 M Latch spring 1 AB5 -4 FDORFB075MRT0 M Door panel 1 AW5 -5 PSHEPB016MRE0 M Sealer film 1 AD5- 6 GCOVHB047MRF0 M Choke cover 1 AH5- 7 LSTPPB045MRF0 M Door stopper 1 AA5- 8 PGLSPB118MRE0 M Door glass (R-520LK) 1 AT5- 8 PGLSPB124MRE0 M Door glass (R-520LW) 1 AT5- 9 LSTPPB036MRF0 M Door glass stopper 1 AC 5- 10 PCUSUB058MRP0 M Door cushion 1 AB 5- 11 XEPS730P06XS0 M Door screw 1 AA

*

40

R - 520LKR-520LW

HOW TO ORDER REPLACEMENT PARTS

Tohaveyourorderfilledpromptlyandcorrectly,pleasefurnishthefollowinginformation.

1.MODELNUMBER.REF.NO.3.PARTNO.4.DESCRIPTION

OrderPartsfromtheauthorizedSHARPpartsDistributorforyourarea.DefectivepartsrequiringreturnshouldbereturnedasindicatedintheServicePolicy.

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

MISCELLANEOUS6- 1 FW-VZB268MRE0 M Main wire harnes 1 AS6- 2 FROLPB025MRK0 M Turntable support 1 AN6- 3 NTNT-A099WRE0 M Turntable tray 1 AT6- 4 TCAUAB050MRR0 M Monitor caution label 1 AA6- 5 TCAUAB053MRR0 M DHHS/Screw caution label 1 AB6- 6 TINSEB449MRK0 M Operation manual 1 AD6- 7 QW-QZB016MRE0 M High voltage wire A 1 AC

SCREWS,NUTS AND WASHERS7- 1 LX-BZA041WRE0 M Special screw 5 AA7- 2 LX-CZ0052WRE0 M Special screw 2 AA7- 3 XHTS740P12RV0 M Screw : 4mm x 12mm 1 AB7- 4 XOTS740P12000 M Screw : 4mm x 12mm 13 AB7- 5 XCBS730P08000 M Screw : 3mm x 8mm 3 AB7- 6 XHTS740P08RV0 M Screw : 4mm x 8mm 3 AB7- 7 LX-CZA070WRE0 M Special screw (Torx tamper proof screw) 2 AC7- 8 XOTS840P12000 M Screw 4 AB

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OVEN AND CABINET PARTS

2-3

4-7

6-5

1-4

4-6

4-8

4-9

6-3

6-22-1

7-5

1-9

4-10

7-2

7-2

7-4

4-3

1-10

1-7

7-3

7-6

7-5

7-6

4-2

7-4

1-8

7-11-6

1-6

4-47-1

4-1

1-1

1-2

2-2

2-2

2-2

2-2

7-4

7-4

4-11

7-4

6-4

1-11

7-4

7-7

7-4

7-7

1-5

1-3

4-5

7-4

7-4

1-13

4-12

1-12

1-5

4-13

7-5

7-21-14

7-8

7-8

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CONTROL PANEL PARTS

DOOR PARTS

MISCELLANEOUS

Actual wire harness may be different from illustration.6-7

6-1

5-5

5-6

5-4

5-9

5-2

5-11

5-1

5-3

5-8

5-10

5-7

3-8

3-9

3-3

3-6

3-10

3-7

3-4

3-2

3-5

3-11

3-1

43

R - 520LKR-520LW

PACKING AND ACCESSORIES

DOOR PROTECTION SHEET

PLASTIC BAG

PACKING CASE

TOP PAD ASSEMBLY

INTO THE OVEN CAVITY

6-3 TURNTABLE TRAY

6-6 OPERATION MANUALBOTTOM PAD ASSEMBLY

TRAY HOLDER

6-2 TURNTABLE SUPPORT

ON TOP OF THE OVEN

Non-replaceable items

44

R - 520LKR-520LW

006SHARPCORP.(5M.00E)PrintedinU.S.A

COPYRIGHT©006BYSHARPCORPORATION

ALLRIGHTSRESERVED.

Nopartofthispublicationmaybereproduced,stored in retrieval systems, or transmittedin any form or by any means, electronic,mechanical, photocopying, recording, orotherwise,withoutpriorwrittenpermissionofthepublisher.

r-520lw service manual - justanswer · (c) before turning on microwave power for any service test...

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