Sharp R-15AT Manuale utente

Marca: Sharp

Modello: R-15AT

Categoria: Microonde

Tipo: Manuale utente

R-15AT

SHARP CORPORATION

SERVICE MANUAL

S0313R15ATPH/

COMMERCIAL

MICROWAVE OVEN

MODEL R-15AT

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

SERVICING ................................................................................................................. INSIDE FRONT COVER

CAUTION, MICROWAVE RADIATION ................................................................................. Indside front cover

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

SERVICING ...................................................................................................................................................... 2

PRODUCT SPECIFICATIONS ..........................................................................................................................5

GENERAL INFORMATION ................................................................................................................................5

APPEARANCE VIEW ....................................................................................................................................... 6

OPERATION SEQUENCE.................................................................................................................................7

FUNCTION OF IMPORTANT COMPONENTS ................................................................................................ 8

TROUBLESHOOTING GUIDE ..........................................................................................................................9

TEST PROCEDURE ....................................................................................................................................... 10

CONTROL PANEL ASSEMBLY .....................................................................................................................16

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE ........................................................... 23

MICROWAVE MEASUREMENT .................................................................................................................... 29

TEST DATA AT A GLANCE ........................................................................................................................... 29

WIRING DIAGRAM ......................................................................................................................................... 30

PICTORIAL DIAGRAM ................................................................................................................................... 31

CPU UNIT CIRCUIT ........................................................................................................................................32

PRINTED WIRING BOARD .............................................................................................................................33

PARTS LIST ................................................................................................................................................... 34

1000W/ R-15AT

DOUBLE

ANTITY

TIM

LEC

ET C

EXPR

ESS

DEFROST

R-15AT

CAUTION

MICROWAVE RADIATION

Personnel should not be exposed to the microwave energy which may radiate from the

magnetron or other microwave generating devices if it is improperly used or connected.

All input and output microwave connections, waveguides, flanges and gaskets must be

secured.

Never operate the device without a microwave energy absorbing load attached.

Never look into an open waveguide or antenna while the device is energized.

VARNING

MICKROVAGSSTRALING

Personal får inte utsättas för mikrovågsenergi som kan ustrala från magnetronen eller

andre mikrovågsalstrande anordningar om dessa är felanslutna eller används på fel sätt.

Alla in-och utgångsanslutningar för mikrovågor, vagledare, flänsar och packningar måste

vara fast anslutna.

Mikrovågsgeneratorn får inte arbeta utan att absorberande belastning är ansluten. Titta

aldrig in i ën öppen vågledare eller antenn när mikrovågsgeneratorn är påkopplad eller

laddad.

VAROITUS

MIKROAALTOSÄTELYÄ

Käyttäjä ei saa joutua alttiiksi mikroaaltoenergialle, jota voi säteillä magnetronista tai

muusta mikroaaltoja kehittävästä laitteesta, jos sitä käytetään tai jos se kytketään väärin.

Kaikkien mikroaaltoliitäntöjen sekä syöttö-että ulostulopuolella, aaltoputkien laippojen ja

tiivisteiden tulee olla varmistettuja.

Mikroaaltouunnia ei koskaan saa käyttää ilman kuormaa jossa mikroaaltoenergiaa kuluu.

Avoimeen aaltoputkeen tai antenniin ei koskaan saa katsoa virran ollessa kytkettynä.

ADVARSEL

MIKROBØLGESTRÅLING

Personell må ikke utsettes for mikrobølge-energi som kan utståles fra magnetronen eller

andre mikrobølge-generende deler dersom apparatet feilbetjenes eller blir feiltikoplet.

Alle inn-og ut-tilkoplinger i forbindelse med mikrobølge-strålingen, bølgeledere, flenser og

tetningsringer/pakninger må festes ordentlig.

Aldri bruk apparatet med mindre en mikrobålge-absorberende last er plassert i

ovnsrommet.

Aldri se direkte inn i en åpen bølgeleder eller antenne imens apparatet er strømførende.

ADVARSEL

MIKROBØLGEBESTRÄLING

Man bør ikke udsætte sig for mikrobølgebestråling fra magnetronen eller andre

mikrobølgefrembringende anordninger, hvilket kan ske hvis apparatet er forkert tilsluttet

eller bruges forkert. Alle mikrobølgeindgange og-udgange, bølgeledere, flanger og

tætningsstrimler må være forsvarligt udført.

Anvend aldrig ovnen uden en mikrobølgesabsorberende anordning. Se aldrig ind i en

åben bølgeleder eller antenne, mens ovnen er i brug.

R-15AT

SERVICE MANUAL

COMMERCIAL

MICROWAVE OVEN

R-15AT

GENERAL IMPORTANT INFORMATION

This Manual has been prepared to provide Sharp Corp. Service

engineers with Operation and Service Information.

It is recommended that service engineers carefully study the entire

text of this manual, so they will be qualified to render satisfactory

customer service.

CAUTION

MICROWAVE RADIATION

DO NOT BECOME EXPOSED TO RADIATION FROM THE

MICROWAVE GENERATOR OR OTHER PARTS THAT CON-

DUCT MICROWAVE ENERGY.

WARNING

Note: The parts marked "*" are used at voltages more

than 250V. (Parts List)

Anm: Delar märket med "*" har en spänning

överstigande 250V.

Huom: Huolto-ohjeeseen merkitty "tähdella" osat joissa

jännite on yli 250 V.

Bemerk: Deler som er merket "asterisk" er utsatt for

spenninger over 250V til jord.

Bemærk: "Dele mærket med stjerne benyttes med højere

spænding end 250 volt.

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 potential above 250V.

All the parts marked "∆" on the parts list may cause undue

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

loosened or removed.

SHARP CORPORATION

OSAKA, JAPAN

SERVICING

PRODUCT SPECIFICATIONS

GENERAL INFORMATION

APPEARANCE VIEW

OPERATING SEQUENCE

FUNCTION OF IMPORTANT

COMPONENTS

TROUBLESHOOTING GUIDE

AND TEST PROCEDURE

TOUCH CONTROL PANEL

COMPONENT REPLACEMENT

AND ADJUSTMENT PROCEDURE

MICROWAVE MEASUREMENT

TEST DATA AT A GLANCE

WIRING DIAGRAM

PARTS LIST

R-15AT

REMEMBER TO CHECK 3D

1) Disconnect the supply.

2) Door opened, and wedged open.

3) Discharge high voltage capacitor.

WARNING: AGAINST THE CHARGE OF THE HIGH-

VOLTAGE CAPACITOR

The high-voltage capacitor remains charged about 60 sec-

onds after the oven has been switched off. Wait for 60

seconds and then short-circuit the connection of the high-

voltage capacitor (that is, of the connecting lead of the high-

voltage rectifier) against the chassis with the use of an

insulated screwdriver.

Sharp recommend that wherever possible fault-finding is

carried out with the supply disconnected. It may, in some

cases, be necessary to connect the supply after the outer

case has been removed, in this case carry out

3D checks and

then disconnect the leads to the primary of the High voltage

transformer. Ensure that these leads remain isolated from

other components and the oven chassis. (Use insulation tape

if necessary.) When the testing is completed carry out 3D

checks and reconnect the leads to the primary of the High

voltage transformer.

SERVICING

WARNING TO SERVICE PERSONNEL

GB Microwave ovens contain circuitry capable of producing very high voltage and current, contact with following parts will

result in electrocution.

High voltage capacitor, High voltage transformer, Magnetron, High voltage rectifier assembly,High voltage fuse, High

voltage harness.

REMEMBER TO CHECK 4R

1) Reconnect all leads removed from components dur-

ing testing.

2) Replace the outer case (cabinet).

3) Reconnect the supply.

4) Run the oven. Check all functions.

Microwave ovens should not be run empty. To test for

the presence of microwave energy within a cavity, place

a cup of cold water on the ceramic shelf, close the door

and set the power to HIGH and set the microwave timer

for one (1) minutes and push the start key. When the two

minutes has elapsed (timer at zero) carefully check that

the water is now hot. If the water remains cold carry out

3D checks and re-examine the connections to the com-

ponent being tested.

When all service work is completed, and the oven is fully

assembled, the microwave power output should be

checked and a microwave leakage test should be car-

ried out.

NL Magnetronovens bevatten circuits die een zeer hoge spanning en stroom kunnen voortbrengen. Contact met de

volgende onderdelen kan elektrocutie tot gevolg hebben.

Hoogspanningscondensator, hoogspanningstransformator, magnetron, hoogspanningsgelijkrichter, hoogspannings

kabelboom.

VERGEET DE VOLGENDE 3 STAPPEN NIET

1) Haal de stekker uit het stopcontact.

2) Open de deur en zorg ervoor dat hij niet dicht kan vallen.

3) Ontlaad de hoogspanningscondensator.

PAS OP VOOR DE ELECTRISCHE LADING VAN DE

HOOGSPANNINGSCONDENSATOR

De hoogspanningscondensator blijft nog ongeveer 60

seconden lang opgeladen, nadat de oven is uitgeschakeld.

Wacht 60 seconden voordat u de verbinding van de

hoogspannings-condensator (m.a.w. de verbindingsdraad

van de hoogspanningsgelijkrichter) met een geïsoleerde

schroevedraaier kortsluit tegen het chassis.

Sharp beveelt ten sterkste aan dat, voor zover mogelijk,

defecten worden opgespoord wanneer de stekker uit het

stopcontact is gehaald. Soms is het nodig om de stroomtoevoer

weer tot stand te brengen nadat de buitenmantel verwijderd

is. Herhaal dan de bovengenoemde 3 stappen en haal de

electrische draden uit de primaire zijde van de

vermogenstransformator. Zorg ervoor dat deze draden

geïsoleerd blijven van andere elementen en van het chassis

van de oven. (Gebruik zo nodig isolatieband.) Wanneer de

test is uitgevoerd, herhaalt u de bovenstaande 3 stappen en

verbindt u de electrische draden weer aan de primaire zijde

van de vermogenstransformator.

VERGEET DE VOLGENDE 4 STAPPEN NIET

1) Sluit de draden weer aan diezijn losgehaald voor de test.

2) Plaats de buitenmantel weer om het toestel heen (kabinet).

3) Stop de stekker weer in het stopcontact.

4) Zet de oven aan. Controleer alle functies.

Magnetronovens mogen niet leeg aangezet worden. Om te

controleren of er microgolf-energie binnen de oven wordt

geproduceerd, plaatst u een mok met koud water op de

draaitafel van de oven, sluit de deur, zet de oven op HIGH en

stelt de klok van de magnetron in op twee (2) minuten. Wanneer

de twee minuten voorbij zijn (klok staat op nul), controleert u

voorzichtig of het water heet is. Indien het water nog steeds

koud is, herhaalt u de allereerste drie stappen en controleer

nogmaals de aansluitingen naar de geteste onderdelen.

Wanneer alle reparaties zijn uitgevoerd en de oven weer in

elkaar is gezet, moet de het magnetronvermogen worden

gecontroleerd en moet worden gecontroleerd of er geen

microgolflekkage is.

R-15AT

E Los hornos de microondas contienen circuitos eléctricos capaces de producir voltajes de alta tensión y descargas

eléctricas. Para evitar el riesgo de electrocución, absténgase de tocar los siguientes componentes: condensador de alta

tensión, transformador de alta tensión, magnetrón, dispositivo del rectificador de alta tensión y arnés de alta tensión.

RECUERDE LA COMPROBACION 3D

1) Desconecte la alimentación.

2) Deje la puerta abierta y calzada.

3) Descargue el condensador de alto voltaje.

ADVERTENCIA SOBRE LA CARGA DEL

CONDENSADOR DE ALTO VOLTAJE

El condensador de alto voltaje permanece cargado unos

60 segundos después de haber apagado el horno. Espere

60 segundos y luego ponga en cortocircuito la conexión del

condensador de alto voltaje (esto es, del conductor de

conexión del rectificador de alto voltaje) al chasis con un

destornillador de mango aislado.

Se recomienda encarecidamente que siempre que sea

posible la localización de fallos se realice con la alimentación

desconectada. Puede ser que en algunos casos sea

necesario conectar la alimentación después de haber retirado

la carcasa exterior. En este caso, realice las comprobaciones

3D y luego desconecte los conductores del primario del

transformador de alimentación. Asegúrese de que estos

conductores permanezcan aislados de otros componentes y

del chasis del horno. (Use cinta aislante si es necesario).

Cuando termine la prueba efectúe las comprobaciones 3D y

reconecte los conductores al primario del transformador de

alimentación.

RECUERDE LA COMPROBACION 4C

1) Conecte todos los componentes desconectados de los

componentes durante la prueba.

2) Coloque la carcasa exterior (cabina).

3) Conecte la alimentación.

4) Compruebe todas sus funciones despues de poner en

marcha el horno.

Los hornos de microondas no deben funcionar vacíos. Para

comprobar la presencia de energía de microondas dentro de

una cavidad, coloque una taza de agua fría en el plato giratorio

del horno, cierre la puerta y ponga la potencia en HIGH (alta)

y coloque el temporizador en dos (2) minutos. Cuando

transcurran los dos minutos (temporizador a cero) compruebe

cuidadosamente que el agua se ha calentado. Si el agua

permaneciese fría, efectúe las comprobaciones 3D y vuelva a

examinar las conexiones de los componentes que han sido

probados.

Cuando haya terminado la intervención en el equipo y el horno

haya sido ensamblado de nuevo completamente, deberá

comprobar la potencia de salida de microondas y realizar una

prueba de fugas de microondas.

SV Mikrovågsugnar innehåller kretsar som producerar mycket höga spänningar och strömmar.

Kontakt med följande komponenter kan leda till dödsfall:

Högspänningskondensator, transformator, magnetron, högspännings likriktare, högspännings kablage.

KOM IHÅG ATT KONTROLLERA 3 STEG

1) Koppla från strömkällan.

2) Öppna dörren på glänt.

3) Ladda ur högspänningskondensatorn.

VARNING FÖR LADDNINGEN I

HÖGSPÄNNINGSKONDENSATORN

Högspänningskondensatorn är laddad i 60 sekunder efter

det att ugnen stängts av. Vänta 60 sekunder och korislut

sedan kondensatoms anslutning (dvs anslutningen till

högspänningslikriktaren) till chassiet med hjälp av en isolerad

skruvmejsel.

Sharp rekommenderar att felsökning sker med strömmen

fränkopplad. Ibland kan det var nödvändigt att koppla på

strömmen efter det att höljet avlägsnats, utför da 3 Steg

kontrollen och koppla sedan från ledarna till transformatorns

primärsida. Se till att ledarna är isolerade från andra

komponenter och chassiet. (Använd isoleringsband om det

behövs). När Du testat färdigt utför Du 3 Steg kontrollen och

ansluter ledningarna till transformatorns primärsida igen.

KOM IHÅG ATT KONTROLLERA 4 STEG

1) Anslut alla ledningar som använts vid testning

2) Sätt tillbaka ytterhöljet.

3) Anslut strömkällan på nytt.

4) Sätt på ugnen. Kontrollera alla funktioner.

Mikrovågsugnar får inte användas tomma. Kontrollera

mikrovågsstrålningen i olika delar av ugnen genom att placera

en kopp med kallt vatten på ugnens tallrik, stäng dörren, ställ

in HIGH och ställ in 2 minuter på timern. När två minuter har gått

(timem visar 0) kontrollerar du om vattnet är varmt. Om vattnet

fortfarande är kallt utför Du 3 steg kontroller och kontrollerar

anslutningarna till varje enskild komponent på nytt.

När all service är klar och ugnen ihopskruvad skall ugnens

uteffekt och eventuellt mikrovågsläckage kontrolleras.

R-15AT

II forni a microonde contengono un circuito elettrico in grado di generare tensioni e correnti estremamente elevate.

L’eventuale contatto con i seguenti componenti può causare la folgorazione:

condensatore ad alta tensione; trasformatore ad alta tensione; magnetron; rettificatore alta tensione; cablaggio ad

alta tensione.

TRE OPERAZIONI IMPORTANTI PER

INCOMINCIARE

1) Scollegare l'alimentazione elettrica.

2) Verificare che la porta sia bloccata in posizione

aperta.

3) Scaricare il condensatore ad alta tensione.

ATTENZIONE AL CONDENSATORE AD ALTA

TENSIONE: PUO ESSERE CARICO

Il condensatore ad alta tensione rimane carico per circa

60 secondi dopo lo spegnimento del forno. Occorre quindi

spettare 60 secondi prima di cortocircuitare, utilizzando

un cacciavite con impugnatura isolata, il collegamento

del condensatore ad alta tensione (cioè del conduttore

di collegamento del raddrizzatore ad alta tensione) sul

telaio del forno.

Sharp raccomanda, nei limiti del possibile, che la ricerca

dei guasti avvenga in assenza di alimentazione elettrica.

In alcuni casi tuttavia, può essere necessario alimentare

l'apparecchio dopo aver rimosso la scatola esterna. In

questo caso eseguire i tre controlli sopra citati e quindi

scollegare i connettori dal primario del trasformatore.

Assicurarsi che tali connettori non vengano a contatto con

altri componenti, ne con il telaio del forno (fare uso, se

necessario, di nastro isolante). Al termine dell'intervento,

eseguire nuovamente i tre controlli e ricollegare i conduttori

al primario del trasformatore.

QUATTRO VERIFICHE IMPORTANTI DA NON

DIMENTICARE

1) Ricollegare tutti i conduttori staccati dai vari componenti

durante l'intervento.

2) Rimontare la scatola esterna.

3) Ripristinare l'alimentazione elettrica.

4) Rimettere in funzione il forno. Controllare tutte le funzioni.

I forni a microonde non devono mai funzionare a vuoto. Per

verificare la presenza di energia da microonde all'interno

di una cavitá, mettere una tazza di acqua fredda sul piatto

rotante del forno, chiudere la porta, regolare la potenza su

HIGH ed impostate il temporizzatore su due (2) minuti.

Trascorsi i due minuti (temporizzatore a zero), controllare

accuratamente che ora l'acqua sia calda. Se l'acqua è

rimasta fredda, eseguire i tre controlli iniziali e verificare

nuovamente i collegamenti del componente in questione.

Dopo aver portato a termine le operazioni di manutenzione

e rimontato il forno, è necessario controllare la potenza delle

microonde emesse ed eseguire un test per verificare che

non vi sia alcuna dispersione.

R-15AT

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

PRODUCT DESCRIPTION

SPECIFICATION

ITEM DESCRIPTION

Power Requirements 230 Volts

50 Hertz

Single phase, 3 wire earthed

Power Comsumption 1.55 KW Approx. 7.0 A

Power Output

1000 W nominal of RF microwave energy (measured by method of IEC 60705)

Operating frequency 2450 MHz

Case Dimensions Width 520 mm

Height 309 mm including foot

Depth 424 mm

Cooking Cavity Dimensions Width 351 mm

Height 211 mm

Depth 372 mm

Control Complement Touch Control System

Timer (0 - 99 minutes and 99 seconds)

Microwave Power for Variable Cooking

Repetition Rate;

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

P-90 ............................................................. approx. 90% of Full Power

P-80 ............................................................. approx. 80% of Full Power

P-70 ............................................................. approx. 70% of Full Power

P-60 ............................................................. approx. 60% of Full Power

P-50 ............................................................. approx. 50% of Full Power

P-40 ............................................................. approx. 40% of Full Power

P-30 ............................................................. approx. 30% of Full Power

P-20 ............................................................. approx. 20% of Full Power

P-10 ............................................................. approx. 10% of Full Power

P-0 ............................................. No power throughout the cooking time

DOUBLE QUANTITY pad

EXPRESS DEFROST pad

Number pads

SELECT TIME pad

STOP/CLEAR pad

SELECT POWER pad

START pad

SET pad

CHECK pad

SIGNAL pad

Set Weight Approx. 18 kg

R-15AT

APPEARANCE VIEW

DISPLAY AND INDICATORS

Check indicators after the oven starts to

oven is operating as desired.

1 Cook indicator

This indicator shows cooking in progress.

2 Express Defrost indicator

3 Memory number indicator

4Double quantity indicator

5 Check mode indicator

6 Digital display

OPERATING KEYS

7 DOUBLE QUANTITY key

8 EXPRESS DEFROST key

9 NUMBER keys

10 SELECT TIME key

11 STOP/CLEAR key

12 SELECT POWER key

13 START key

14 SET key

15 CHECK key

16 SIGNAL key

OVEN

1. Oven light

2. Ceramic shelf

3. Control panel

4. Cavity face plate

5. Door latch openings

6. Door latches

7. Door hinges

8. Door seals and sealing surfaces

9. Door handle

10.Oven door with see-through window

11.Air ventilation cover and openings

12.Power supply cord

13.Air intake openings

14.Outer case cabinet

TOUCH CONTROL PANEL

710

INSTALLATION INFORMATION

When this commercial microwave oven is installed near other commercial electrical appliances, connect a lead wire to

each equivalent potential terminal with equipotential marking between them (insert a lead wire between a washer and

an earth angle, and screw them), as shown in Fig. A-1, to make sure that they are at equivalent potential.

If any lead wire is not connected between them, when person touch them he/she will get a electric shock.

COMMERCIAL MICROWAVE OVEN OTHER COMMERCIAL

ELECTRICAL APPLIANCE

Lead wire

Equipotential marking

Earth angle

(Equipotential terminal)

Equipotential

terminal

Screw

Washer

Lead wire

DEF

NO.

CHECK

2 3 4 5

R-15AT

OPERATION SEQUENCE

OFF CONDITION

Closing the door activates the primary interlock relay

control switch SW1 and 2nd. interlock switch SW2 .

IMPORTANT:

When the oven door is closed, the contacts COM-NC

of the monitor switch SW3 must be open. When the

microwave oven is plugged in a wall outlet (230V

50Hz), the line voltage is supplied to the noise filter

and the control unit

Figure O-1 on page 30

1. The oven display will show . .

MICROWAVE COOKING CONDITION

Program desired cooking time by touching SELECT TIME

pad and the NUMBER pads. When the START pad is

touched, the following operations occur:

Figure O-2 on page 30

RELAY CONNECTED COMPONENTS

RY-2 High voltage transformer

RY-3 Oven lamp/Antenna motor/Fan motor

1. The line voltage is supplied to the primary winding of

the high voltage transformer. The voltage is converted

to about 3.3 volts A.C. output on the filament winding

and high voltage of approximately 2300 volts A.C. on

the secondary winding.

2. The filament winding voltage (3.3 volts) heats the

magnetron filament and the high voltage (2000 volts) is

sent to the voltage doubling circuit, where it is doubled

to negative voltage of approximately 4000 volts D.C..

3. The 2450 MHz microwave energy produced in the

magnetron generates a wave length of 12.24 cm. This

energy is channelled through the waveguide (transport

channel) into the oven cavity, where the food is placed

to be cooked.

4. When the cooking time is up, a signal tone is heard and

the relays RY2 + RY3 go back to their home position.

The circuits to the oven lamp, high voltage transformer,

fan motor and antenna motor are cut off.

5. When the oven door is opened during a cooking cycle,

the switches come to the following condition.

Switch Contact Condition

During Oven Door

Cooking Open(No cooking)

primary

interlock relay

control switch

COM-NO Closed Opened

2nd.

interlock switch COM-NO Closed Opened

Monitor Switch COM-NC Opened Closed

The circuit to the high voltage transformer, fan motor and

antenna motor are cut off when the 2nd. interlock switch

SW2 is made open. The oven lamp remains on even if the

oven door is opened after the cooking cycle has been

interrupted, because the relay RY-3 stays closed. Shown

in the display is remaining time.

6. MONITOR SWITCH CIRCUIT

The monitor switch SW3 is mechanically controlled by

the oven door, and monitors the operation of the 2nd.

interlock switch SW2.

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

cycle of a cooking program, the 2nd. interlock switch

SW2 and primary interlock relay control switch SW1

must open their contacts first. After that the contacts

(COM-NC) of the monitor switch SW3 can be closed.

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

NC) of the monitor switch SW3 must be opened. After

that the contacts of the 2nd. interlock switch SW2, and

primary interlock relay control switch SW1 are closed.

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

2nd. latch switch SW2 and the relay RY3 remain

closed, the fuse F10A will blow, because the monitor

switch SW3 is closed and a short circuit is caused.

POWER LEVEL P-0 TO P-90 COOKING

When Variable Cooking Power is programmed, the line

voltage is supplied to the power transformer intermittently

through the contacts of relay (RY-2) which is operated by

the control unit within a 32 second time base. Microwave

power operation is as follows:

VARI-MODE ON TIME OFF TIME

Power 10(P-HI) 32 sec. 0 sec.

(100% power)

Power 9(P-90) 30 sec. 2 sec.

(approx. 90% power)

Power 8(P-80) 26 sec. 6 sec.

(approx. 80% power)

Power 7(P-70) 24 sec. 8 sec.

(approx. 70% power)

Power 6(P-60) 22 sec. 10 sec.

(approx. 60% power)

Power 5(P-50) 18 sec. 14 sec.

(approx. 50% power)

Power 4(P-40) 16 sec. 16 sec.

(approx. 40% power)

Power 3(P-30) 12 sec. 20 sec.

(approx. 30% power)

Power 2(P-20) 8 sec. 24 sec.

(approx. 20% power)

Power 1(P-10) 6 sec. 26 sec.

(approx. 10% power)

Power 0(P-0) 0 sec. 32 sec.

(0% power)

Note: The ON/OFF time ratio does not correspond with

the percentage of microwave power, because

approx. 2 seconds are needed for heating of the

magnetron filament.

R-15AT

DOOR OPEN MECHANISM

The door is opened by grasping the door handle, refer to

Figure D-1.

When the door handle is grasped, the handle lever is

pulled. And then the upper and lower latch heads are

moved upward by the handle lever, and they are re-

leased from the latch hook. Now the door will open.

Figure D-1. Door Open Mechanism

2ND. INTERLOCK SWITCH SW2 AND PRIMARY

INTERLOCK RELAY CONTROL SWITCH SW1

1. When the oven door is closed, the contacts (COM-NO)

of each switch must be closed.

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

NO) of each switch must be opened.

MONITOR SWITCH SW3

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

be opened.

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

must be closed.

3. If the oven door is opened and the contacts (COM-NO)

of the 2nd. interlock switch SW2 and the relay RY-3 fail

to open, the fuse F10A blows immediately after closing

the contacts (COM-NC) of the monitor switch SW3.

CAUTION: BEFORE REPLACING A BLOWN FUSE F10A

TEST THE 2ND. INTERLOCK SWITCH SW2,

MONITOR SWITCH SW3 AND RELAY RY-3

FOR PROPER OPERATION. (REFER TO

CHAPTER “TEST PROCEDURE”).

FUSE F1 F10A 250V

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

circuited, this fuse blows to prevent an electric shock or

fire hazard.

2. This fuse blows when the 2nd. interlock switch SW2

remain closed with the oven door open and when the

contacts (COM-NC) of monitor switch SW3 closes.

FUNCTION OF IMPORTANT COMPONENTS

HIGH VOLTAGE FUSE F2 0.75A

The high voltage fuse blows when the high voltage rectifier

or the magnetron is shorted.

THERMAL CUT-OUT TC2 145˚C (MAGNETRON)

This thermal cut-out protects the magnetron against over-

heating. If the temperature goes up higher than 145˚C

because the fan motor is interrupted or the ventilation

openings are blocked, the thermal cut-out will open and

line voltages to the high voltage transformer will be cut off

and the operation of the magnetron will be stopped. The

thermal cut-out will not resume.

THERMAL CUT-OUT TC1 125˚C (OVEN)

The thermal cut-out located on the top of the oven cavity

is designed to prevent damage to the oven if the food in the

oven catches fire due to over heating produced by im-

proper setting of the cooking time or failure of control unit.

Under normal operation, the oven thermal cut-out re-

mains closed. However, when abnormally high tempera-

tures are reached within the oven cavity, the oven thermal

cut-out will open at 125˚C causing the oven to shut down.

The thermal cut-out will not resume.

NOISE FILTER

The noise filter assembly prevents radio frequency inter-

ference that might flow back in the power circuit.

ANTENNA MOTOR AM

The antenna motor rotates the stirrer antenna located on

the bottom of the oven cavity, so that the food on the

ceramic shelf is cooked evenly during cooking. The an-

tenna motor may turn in either direction.

COOLING FAN MOTOR FM

The cooling fan motor drives a blade which draws exter-

nal cool air. This cool air is directed through the air vanes

surrounding the magnetron and cools the magnetron.

This air is channelled through the oven cavity to remove

steam and vapors given off from the heating food. It is

then exhausted through the exhausting air vents at the

oven cavity.

Latch Hook

Latch Switch

Lever A

Latch Switch

Lever B

Latch Switch

Lever C

Latch Head

Handle

Lever

Door

Handle

Latch

Lever

SW2: 2nd. Interlock Switch

SW3: Monitor Switch

SW1:

Primary Interlock Relay

Control Switch

R-15AT

TROUBLESHOOTING GUIDE

When troubleshooting the microwave oven, it is helpful to follow the Sequence of Operation in performing the checks.

Many of the possible causes of trouble will require that a specific test be performed. These tests are given a procedure

letter which will be found in the “Test Procedure” section.

IMPORTANT: If the oven becomes inoperative because of a blown fuse F1 (F10A) in the 2nd. interlock switch SW2 -

monitor switch SW3 - relay RY3 circuit, check the 2nd. interlock switch SW2, monitor switch SW3 and

relay RY3 before replacing the fuse F1 (F10A).

TEST PROCEDURE

CONDITION

PROBLEM

POSSIBLE CASE

AND

DEFECTIVE PARTS

Home fuse or circuit

breaker blows when

power cord is plugged into

wall outlet.

Fuse F1 F10A blows when

power cord is plugged into

wall receptacle.

. does not appear

in display when power

cord is first plugged into

wall outlet.

Oven lamp does not light

when door is opened.

Oven lamp lights but fan

motor and antenna motor

do not operate.

Oven does not go into

cook cycle when START

pad is touched.

Oven seems to be

operating but little or no

heat is produced in oven

load. (Food incompletely

cooked or not cooked at

all at end of cook cycle.)

Oven goes into a cook

cycle but extremely

uneven heating is

produced in oven load

(food).

Oven does not cook prop-

erly when programmed for

Cooking Power 5 mode.

(Operates properly on

Cooking Power HI (HIGH)

mode.)

"EE9" Maximum time is

exceeded.

OFF

CONDITION

COOKING

CONDITION

ERROR MODE

MAGNETRON

HIGH VOLTAGE TRANSFORMER

H.V. RECTIFIER ASSEMBLY

HIGH VOLTAGE CAPACITOR

THERMAL CUT-OUT

2ND. INTERLOCK SWITCH

PRIMARY INTERLOCK RELAY

FUSE F1 F10A

HIGH VOLTAGE FUSE

NOISE FILTER

TOUCH CONTROL PANEL

KEY UNIT

EXCEED MAX. HEATING TIME

RELAY (RY3)

RELAY (RY2)

FOIL PATTERN ON P.W.B.

LOW VOLTAGE

WRONG OPERATION

DIRTY OVEN CAVITY

MISADJUSTMENT SWITCH

SHORTED IN POWER CORD

OVEN LAMP OR SOCKET

COOLING FAN MOTOR

ANTENNA MOTOR

SHORT OR OPENED WIRING

MONITOR SWITCH

CONTROL SWITCH

ABC DE E E F GH I I

K L M M N CK RE RERECKCKCKCK

R-15AT

A MAGNETRON TEST

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

CARRY OUT

3D CHECKS.

Isolate the magnetron from high voltage circuit by removing all leads connected to filament terminal.

To test for an open circuit filament use an ohmmeter to make a continuity test between the magnetron

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

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

terminals and the case of the magnetron (ground). This test should be indicated an infinite resistance.

If a low or zero resistance reading is obtained then the magnetron should be replaced.

MICROWAVE OUTPUT POWER (1 litre load, IEC60705 procedure)

The following test procedure should be carried out with the microwave oven in a fully assembled

condition (outer case fitted). Microwave output power from the magnetron can be measured by way

of IEC 60705, i.e. it is measured by how much power the water load can absorb. To measure the

microwave output power in the microwave oven, the relation of calorie and watt is used. When P(W)

heating works for t(second), approximately P x t/4.187 calorie is generated. On the other hand, if the

temperature of the water with V(ml) rises ∆T (°C) during this microwave heating period, the calorie of

the water is V x ∆T.

Measuring condition:

1. Container

The water container must be a cylindrical borosilicate glass vessel having a maximum material

thickness of 3 mm and an outside diameter of approximately 190 mm.

2. Temperature of the oven and vessel

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

3. Temperature of the water

The initial temperature of the water is (10±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. Select stirring devices and measuring instruments in order to minimize addition or removal of heat.

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

thermometer.

7. The water load must be (1000±5) g.

8. “t” is measured while the microwave generator is operating at full power. Magnetron filament heat-

up time is not included.

NOTE: The operation time of the microwave oven is “t + 3” sec. (3 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˚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.

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

WHILE THE OVEN IS IN OPERATION.

The formula is as follows;

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

P (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°CPower supply Voltage .............. Rated voltage

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

Heating time .............................. 42 sec. Mass of container (mc) ......................... 330 g

T2 ............................ Final Temperature P = 100 x ∆T + 0.55 x mc (T2-T0)/42

R-15AT

Room temperature ................................................................................................. To = 21˚C

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

Temperature after (42 + 3) = 45 sec ...................................................................... T2 = 21°C

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

Measured output power

The equation is “P = 100 x ∆T” ................................................ P = 100 x 10°C = 1000 Watts

JUDGMENT: The measured output power should be within the range of ± 15 % of the rated output

power.

CAUTION: 1°C CORRESPONDS TO 100 WATTS. REPEAT MEASUREMENT IF THE POWER IS

INSUFFICIENT.

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

1000g

T1˚C

T2˚C

Heat up for 45 sec

B HIGH VOLTAGE TRANSFORMER TEST

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

filament winding of the high voltage 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.

C HIGH VOLTAGE RECTIFIER ASSEMBLY TEST

CARRY OUT 3D CHECKS.

Isolate the high voltage rectifier assembly from the HV circuit. The high voltage rectifier can be tested

using an ohmmeter set to its highest range. Connect the ohmmeter across the terminal B+C of the high

voltage rectifier and note the reading obtained. Reverse the meter leads and note this second reading.

The normal resistance is infinite in one direction and more than 100 kΩ in the other direction.

CARRY OUT 4R CHECKS.

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

THE MEASURING INSTRUMENT MUST HAVE A VOLTAGE AT LEAST 6 VOLTS, BE-

CAUSE OTHERWISE AN INFINITE RESISTANCE MIGHT BE SHOWN IN BOTH DIREC-

TIONS.

CARRY OUT 3D CHECKS.

Disconnect the leads to the primary winding of the high voltage 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 ................................ approximately 1.3 Ω

b. Secondary winding ............................. approximately 90Ω

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

If the readings obtained are not stated as above, then the high voltage transformer is probably faulty

and should be replaced.

CARRY OUT 4R CHECKS.

HIGH VOLTAGE RECTIFIER

D HIGH VOLTAGE CAPACITOR TEST

CARRY OUT 3D CHECKS.

A. Isolate the high voltage capacitor from the circuit.

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

resistance range.

R-15AT

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

E SWITCH TEST

CARRY OUT 3D CHECKS.

Isolate the switch to be tested and using an ohmmeter check between the terminals as described in

the following table.

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

CARRY OUT 4R CHECKS.

F THERMAL CUT-OUT TEST

CARRY OUT 3D CHECKS.

Disconnect the leads from the terminals of the thermal cut-out. Then using an ohmmeter, make a continuity

test across the two terminals as described in the below.

Table: Thermal Cut-out Test

Temperature of "ON" Temperature of "OFF" Indication of ohmmeter

Parts Name condition (closed circuit). condition (open circuit). (When room temperature

(˚C) (˚C) is approx. 20˚C.)

Thermal cut-out TC1125˚C

This is not resetable type. Above 125˚C Closed circuit

Thermal cut-out TC2 145˚C

This is not resetable type. Above 145˚C Closed circuit

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

An open circuit thermal cut-out TC2 (MG) indicates that the magnetron has overheated, this may be

due to resistricted ventilation, cooling fan failure or a fault condition within the magnetron or HV. circuit.

An open circuit thermal cut-out TC1 (OVEN) indicates that the food in the oven cavity may catch fire,

this may be due to over heating produced by improper setting of the cooking timer or failure of the

control panel.

CARRY OUT 4R CHECKS.

G BLOWN FUSE F1 F10A

CARRY OUT 3D CHECKS.

If the fuse F1 F10A is blown when the door is opened, check the 2nd. interlock switch SW2, monitor

switch SW3 and relay RY-3.

If the fuse F1 F10A is blown, there could be a short or ground in electrical parts or wire harness. Check

them and replace the defective parts or repair the wire harness.

CARRY OUT 4R CHECKS.

CAUTION: Only replace fuse

F1 F10A with the correct value replacement.

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

after it has been charged.

D. A short-circuited capacitor shows continuity all the time.

E. An open capacitor constantly shows a resistance about 10 MΩ because of its internal 10MΩ

resistance.

F. When the internal wire is opened in the high voltage capacitor shows an infinite resistance.

G. The resistance across all the terminals and the chassis must be infinite when the capacitor is

normal.

If incorrect reading are obtained, the high voltage capacitor must be replaced.

CARRY OUT 4R CHECKS.

Table: Terminal Connection of Switch

Plunger Operation COM to NO COM to NC

Released Open circuit Short circuit

Depressed Short circuit Open circuit

COM; Common terminal,

NO; Normally open terminal

NC; Normally close terminal

R-15AT

CARRY OUT 3D CHECKS.

Disconnect the leads from the motor. Using an ohmmeter, check the resistance between the two

terminals as described in the table below.

Table: Resistance of Motor

Motors Resistance

Fan motor Approximately 219 Ω

Antenna motor Approximately 11 kΩ

If incorrect readings are obtained, replace the motor.

CARRY OUT

4R CHECKS.

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

I MOTOR WINDING TEST

CARRY OUT 3D CHECKS.

Disconnect the leads from the terminals of noise filter.

Using an ohmmeter, check between the terminals as described

in the following table.

MEASURING POINTS INDICATION OF OHMMETER

Between N and L Approx. 680 kΩ

Between terminal N and WHITE Short circuit

Between terminal L and RED Short circuit

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

CARRY OUT

4R CHECKS.

H NOISE FILTER TEST

J HIGH VOLTAGE FUSE F2 TST

CARRY OUT 3D CHECKS.

If the high voltage fuse F2 is blown, there could be a short in the high voltage rectifier or the magnetron.

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

CARRY OUT 4R CHECKS.

CAUTION: Only replace high voltage fuse with the correct value replacement.

The touch control panel consists of circuits including semiconductors such as LSI, ICs, etc. Therefore,

unlike conventional microwave ovens, proper maintenance can not be performed with only a voltmeter

and ohmmeter.

In this service manual, the touch control panel assembly is divided into two units, Control Unit and Key

Unit and troubleshooting by replacement is described according to the symptoms indicated.

1. Key Unit Note : Check key unit ribbon connection before replacement.

The following symptoms indicate a defective key unit. Replace the key unit.

a) When touching the pads, a certain pad produces no signal at all.

b) When touching a number pad, two figures or more are displayed.

c) When touching the pads, sometimes a pad produces no signal.

2. Control Panel

The following symptoms indicate a defective control unit. Before replacing the control unit.

perform the key unit test (Procedure L) to determine if control unit is faulty.

2-1 In connection with pads

a) When touching the pads, a certain group of pads do not produce a signal.

b) When touching the pads, no pads produce a signal.

2-2 In connection with indicators

a) At a certain digit, all or some segments do not light up.

b) At a certain digit, brightness is low.

c) Only one indicator does not light up.

d) The corresponding segments of all digits do not light up; or they continue to light up.

K TOUCH CONTROL PANEL ASSEMBLY TEST

F1: FUSE

F10A

DISCHARGE RESISTOR 680 kΩ 1/2W

NOISE SUPPRESSION COIL

LINE BYPASS

CAPACITOR

0.0033µF/ AC 250V

DISCHARGE

RESISTOR 10MΩ 1/2W

WHT RED

LINE BYPASS

CAPACITOR

0.0033µF/ AC 250V

LINE CROSS CAPACITOR 0.22µF/ AC 250V

NOISE FILTER

R-15AT

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

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.

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

is marking good contact, verify that the primary interlock relay control switch operates properly; that

is the contacts are closed when the door is closed and open when the door is open. If the primary

interlock relay control switch is good, disconnect the flat ribbon cable that connects the key unit to the

control unit and make sure the primary interlock relay control switch is closed (either close the door

or short the primary interlock relay control switch connecter). Use the Key unit matrix indicated on the

control panel schematic and place a jumper wire between the pins that correspond to the STOP/

CLEAR pad marking momentary contact. If the control unit responds by clearing with a beep the key

unit is faulty and must be replaced. If the control unit does not respond, it is a faulty and must be

replaced. If a specific pad does not respond, the above method may be used (after clearing the control

unit) to determine if the control unit or key pad is at fault.

L KEY UNIT TEST

CARRY OUT

4R CHECKS.

M RELAY TEST

11131519

12141620

G12

G11

G10

G 9

G 1 G 2 G 3 G 4 G 5 G 6 G 7 G 8

DOUBLE

QUANTITY

EXPRESS

DEFROST

SELECT

POWER

START

SET

CHECK

SIGNAL

STOP/

CLEAR

SELECT

TIME

CARRY OUT 3D CHECKS.

Remove the outer case and check voltage between Pin Nos. 3 and 7 of the 3 pin connector (A) on the

control unit with an A.C. voltmeter.

The meter should indicate 230 volts, if not check oven circuit.

Relay Test

Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation.

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

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

control unit is defective.

RELAY SYMBOL OPERATIONAL VOLTAGE CONNECTED COMPONENTS

RY2 Approx. 18.0V D.C. High voltage transformer

RY3 Approx. 18.0V D.C. Oven lamp / Antenna motor / Fan motor

CARRY OUT 4R CHECKS.

R-15AT

TEST PROCEDURES

PROCEDURE

LETTER COMPONENT TEST

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

(PWB) IS OPEN

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

on the PWB, this foil pattern acts as a fuse. If the foil pattern is open, follow the troubleshooting guide

given below for repair.

Problem: POWER ON, indicator does not light up.

CARRY OUT 3D CHECKS.

STEPS OCCURRENCE CAUSE OR CORRECTION

The rated AC voltage is not present at

Check supply voltage and oven power cord.

Power terminal of CPU connector (CN-A).

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

side of low voltage transformer. Check and repair.

3 Only pattern at "a" is broken.

*Insert jumper wire J1 and solder.

(CARRY OUT 3D CHECKS BEFORE REPAIR)

4Pattern at "a" and "b" are broken.

*Insert the coil RCILF2003YAZZ between "c" and "d".

(CARRY OUT 3D CHECKS BEFORE REPAIR)

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

visual inspection of the varistor for

burning damage and examine the

transformer with tester for the pres-

ence of layer short circuit (check pri-

mary coil resistance).

If any abnormal condition is detected,

replace the defective parts.

CARRY OUT 4R CHECKS.

(17)

(CT1)

(J1)

(J2)

(TB1)

VRS1

(VRS2)

POWER

R-15AT

11) Relay Driving Circuit

This is a circuit for driving output relay by IC1 output.

12) Primary Interlock Relay Control Switch Circuit

This is a circuit for driving IC1 to detect door opening/

closing.

2. Key Unit

The key unit is composed of a matrix circuit in which

when a key it touched, one of signals P30--P34 gener-

ated by the LSI, is passed through the key and returned

to the LSI as one of signals P24--P27.

This model has 20 Memory pads.

When the oven is shipped, Memory pad 1 to 10 are set

as follows: fig.1.

Memory No. Cook Time Output Power

1 10 sec. 100%

2 20 sec. 100%

3 30 sec. 100%

4 45 sec. 100%

51 min. 100%

61 min. 15 sec. 100%

71 min. 30 sec. 100%

82 min. 100%

92 min. 30 sec. 100%

03 min. 100%

(fig. 1)

This model has a double quantity pad. When the oven

is shipped, Magnification "1.7" is preset in the double

quantity pad.

This model has an express defrost pad. When the oven

is shipped, express defrost is set as follows: fig.2.

1 STAGE 2 STAGE 3 STAGE

FORMULA P = 0.2T P = 0.15T P = 0.65T

POWER 60 % 40 % 20 %

T : Total cooling time

(fig. 2)

When 1/2 total cooking time is passed, the signal

will sound and "CHECK" indicator will flash

TOUCH CONTROL PANEL ASSEMBLY

OUTLINE OF TOUCH CONTROL PANEL

The touch control section consists of the following units as

shown in the touch control panel circuit.

(1) Control Unit

(2) Key Unit

The principal functions of these units and the signals

communicated among them are explained below.

1. Control Unit

Signal of key touch and oven function control are all

processed by one microcomputer.

1) Power Supply Circuit

This circuit changes output voltage at the secondary

side of the low voltage (T1) transformer to voltages

required at each part by full wave rectifying circuit,

constant voltage circuit, etc..

2) Reset Circuit

This is a reset circuit, which enables IC1 to be acti-

vated from initial state.

3) Power SYNC Signal Generating Circuit

This is a circuit for generating power SYNC signal by

virtue of the secondary side output of transformer T1.

This signal is used for a basic frequency to time

processing and so on.

4) Clock Circuit

This is a circuit for controlling clock frequency required

for operating IC1.

5) IC1 (Main Processor)

This is a one-chip microcomputer, responsible for

controlling the entire control unit.

6) IC2 (Memory Processor)

This is a memory IC, responsible for memory function.

7) IC3

This is a IC for driving light emitting diode.

8) Display Circuit

This is a circuit for driving light emitting diode by IC1

output.

9) Key Input Circuit

This is a circuit for transmitting key input information to

IC1.

10) Sound-body Driving Circuit

This is a circuit for driving sound body by IC1 output.

DESCRIPTION OF LSI

LSI(IZA897DR)

The I/O signal of the LSI(IZA897DR) is detailed in the following table.

Pin No. Signal I/O Description

1 VCC IN Power source voltage: +5V.

VC voltage of power source circuit input.

2/3 VEE/AVSS IN Connected to GND

4 VREF IN Connected to VC. (+5V)

5-6 AN7-AN6 IN Terminal not used.

R-15AT

7-8 AN5-AN4 IN Terminal to change functions according to the model.

Signal in accordance with the model in operation is applied to set up its function.

9-10 AN3-AN2 IN Terminal not used.

11 AN1 IN Input signal which communicates the door open/close information to LSI.

Door closed; "L" level signal (0V).

Door opened; "H" level signal (+5V).

12 AN0 IN Terminal not used.

13 P55 OUT Magnetron high-voltage circuit driving signal.

To turn on and off the cook relay. In 100% power level operation, "H" level during

cooking; "L" level otherwise. In other power level operation

(90,80,70,60,50,40,30,20,10 or 0%), "H" and "L" level is repeated according to power

level.

Power level ON OFF Power level ON OFF

100% 32sec. 0sec. 40% 16sec. 16sec.

90% 30sec. 2sec. 30% 12sec. 20sec.

80% 26sec. 6sec. 20% 8sec. 24sec.

70% 24sec. 8sec. 10% 6sec. 26sec.

60% 22sec. 10sec. 0% 0sec. 32sec.

50% 18sec. 14sec.

14-15 P54-P53 OUT Terminal not used.

16-18 P52-P50 IN Terminal not used.

19 P47 OUT Signal to sound buzzer.

This signal is to control the 2.5kHz con-

tinuous signal through IC3.

A: key touch sound.

B: Guidance sound.

C: Completion sound.

20 P46 OUT Oven lamp, Fan motor and Antenna motor driving signal. (Square Waveform :

50Hz)

To turn on and off the shut-off relay (RY3). The

Square waveform voltage is delivered to the

RY3 driving circuit and relays(RY2, COOK RE-

LAY) control circuit.

21 P45 OUT Digit selection signal.

The relation between digit signal and digit are

as follows:

Digit signal Digit

P42 ..................... 1st.

P43 .................... 2nd.

P44 ..................... 3rd.

P45 ..................... 4th.

Normally, one pulse is output in every ß

period, and input to the grid of the light-

emitting diode.

22-24 P44-P42 OUT Digit selection signal.

Signal similar to P45.

25 INT1 IN Signal synchronized with commercial power source frequency.

This is basic timing for all time processing of LSI.

26 P40 IN Connected to GND through resistor.

Pin No. Signal I/O Description

+5V

GND

32 sec.

OFF

0.12 sec

2.4 sec

1.2 sec

+5V

GND

200µsec.

1.2 sec

+5V

GND

+5V

GND

20.0 msec

During cooking

+5V

ß(50Hz)

P42

P43

P44

P45

GND

H : +5V

L : GND

20 msec

R-15AT

27 RESET IN Auto clear terminal.

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

set to "L" level the moment power is supplied, at this time the LSI is reset. Thereafter

set at "H" level.

28 P71 OUT Memory (EEPROM) clock output.

29 P70 IN/OUT Memory (EEPROM) data input/output.

30 XIN IN Internal clock oscillation frequency setting input.

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

with respect to XOUT terminal.

31 XOUT OUT Internal clock oscillation frequency control output.

Output to control oscillation input of XIN.

32 VSS IN Connected to GND.

33 P27 IN Signal coming from touch key.

When either one of G-12 line keys on key matrix is touched, a corresponding signal

out of P30, P31, P32, P33, P34 will be input into P27. When no key is touched, the

signal is held at "L" level.

34 P26 IN Signal similar to P27.

When either one of G-11 line keys on key matrix is touched, a corresponding signal

will be input into P26.

35 P25 IN Signal similar to P27.

When either one of G-10 line keys on key matrix is touched, a corresponding signal

will be input into P25.

36 P24 IN Signal similar to P27.

When either one of G-9 line keys on key matrix is touched, a corresponding signal

will be input into P24.

37-38 P23-P22 OUT Terminal not used.

39-40 P21-P20 OUT Segment data signals.

The relation between signals and indicators are as follows:

Signal Segment Signal Segment

P21,P20 .......... 1 P07,P06 .............6

P17.P16 .......... 2 P05,P04 .............7

P15,P14 .......... 3 P03,P02 .............8

P13,P12 .......... 4 P01,P00 .............9

P11,P10 .......... 5

41-48 P17-P10 OUT Segment data signal.

Signal similar to P21.

49-56 P07-P00 OUT Segment data signal.

Signal similar to P21.

57-59 P37-P35 OUT Terminal not used.

60 P34 OUT Key strobe signal.