Panasonic NN-A890WB Service Manual
  1. Manuals
  2. Brands
  3. Panasonic Manuals
  4. Microwave Oven
  5. NN-A890WB
  6. Service manual
Panasonic NN-A890WB Service Manual

Panasonic NN-A890WB Service Manual

Hide thumbs
Table of Contents
  • Inverter Warning
  • Feature Chart
  • Word Prompting
  • Setting the Clock
  • Schematic Diagram
  • Wiring Diagram
  • Variable Power Cooking Control
  • Grill Cooking
  • Auto Weight Defrost, Auto Weight Cook
  • Convection Cooking
  • Cautions to be Observed When Troubleshooting
  • Check the Grounding
  • Parts Replacement Procedure
  • Component Test Procedure
  • Measurements and Adjustments
  • Troubleshooting Guide
  • Door Assembly
  • Escutcheon Base Assembly
  • Packing and Accessories

Advertisement

Available languages
  • EN

Available languages

Quick Links

Download this manual
Order Number MOP00100021C2
Microwave Oven
NN-A890WB / NN-A860WB
SPG Scandinavian Countries
WPG Switzerland
SPECIFICATIONS
1

Advertisement

Table of Contents
loading

Related Manuals for Panasonic NN-A890WB

Summary of Contents for Panasonic NN-A890WB

  • Page 1 Order Number MOP00100021C2 Microwave Oven NN-A890WB / NN-A860WB SPG Scandinavian Countries WPG Switzerland SPECIFICATIONS...
  • Page 3 2000 Matsushita Electric Industrial Co., Ltd. All rights reserved. Unauthorized copying and distribution is a violation of law.

  • Page 4: Inverter Warning

    1. Inverter Warning The inverter board looks like a regular PCB, however, this PCB drives the magnetron tube using very high voltages and current. It has 1. Very high voltage and high current 2. An Aluminium heat sink that becomes very hot 3.

  • Page 5: Feature Chart

    Inverter Gounding Figure 2 Inverter PCB layout 2. Feature Chart...

  • Page 6: Word Prompting

    Function NN-A890WB NN-A860WB SPG/WPG SPG/WPG Microwave Grill Convection Combination Sensor Reheat Sensor Cook Sensor Combination Sensor Crisp Weight Defrost Weight Combination Weight Reheat Weight Cook Memory Cook Weight Crisp Stage Cooking Delay/Stand More/Less Clock Function NN-A890WB NN-A860WB SPG/WPG SPG/WPG Word Prompt...
  • Page 7 4.3. Microwave Cooking 4.4. Auto Weight Defrost 4.5. Delay Stand...
  • Page 8 4.6. Delay Start 4.7. Child Lock 4.8. Grill Operation 4.9. Convection Operation...
  • Page 9 4.10. Turbo Bake Operation 4.11. Combination Cooking (Convection and Microwave) 4.12. Combination Cooking (Grill and Microwave)
  • Page 10 4.13. Combination Cooking (Turbo Bake and Microwave) 4.14. Memory...

  • Page 11: Schematic Diagram

    4.15. Auto Weight Cook Programs (NN-A860WB) 4.16. Auto Weight Cook Program (NN-A890WB) 4.17. Auto Sensor and Sensor Combi Programs (NN-A890WB) 5. Schematic Diagram...

  • Page 12: Wiring Diagram

    6. Wiring Diagram 7. Description of Operating instruction 7.1. Variable power cooking control The HIGH VOLTAGE INVERTER POWER SUPPLY controls the output power by a signal from the digital Programmer circuit DPC. The power relay (RY1) turns on to supply power to the inverter circuit.

  • Page 13: Auto Weight Defrost, Auto Weight Cook

    Note: After auto cooking if the oven temperature is over the predetermined temperature the fan motor rotates to cool the oven and its components. Auto Weight Defrost NN-A890WB Category 1st Touch Cooking Weight Time 1.Reheat...

  • Page 14: Convection Cooking

    Category 1st Touch Cooking Weight Time 3.Fresh Vegatables 8m 40s 4.Root Vegetables 9m 30s 5.Potatoes 6.Fish 7.Rice 7m 32s 8.Rice Pudding 32m 20s 9.Roast Pork 1000 33m 20s 10.Roast Beef 16m 25s 11.Poultry 17m 10s 12.Frozen Chicken 22m 50s Pieces 13.Pasta Gratin 1000 21m 22s...
  • Page 15 Convection Cooking Duty Cycles 7.5. Combination Cooking Combination cooking is achieved by operating the microwave and heater modes together during one cooking cycle. There are three combination modes. 1. Combination (convection and microwave) 2. Combination (grill and microwave) 3. Combination (grill, convection and microwave) The digital programmer circuit operators the power relays as shown in the figures below.
  • Page 16 Grill And Microwave Combination Duty Cycles Grill Heater Micropower OUTPUT ON Grill 1 Grill 2 440W 360W Grill 3 250W 360W 100W 360W Grill Convection And Microwave Combination Duty Cycles Convection Grill Heater Micropower Heater 100 - 250 C ON OFF OUTPUTON OFF Grill 51 15...
  • Page 17 Grill,Convection and microwave duty cycles 7.6. One touch Auto sensor cooking NN-A890WB Auto sensor cook is a revolutionary way to cook by microwave without setting a power level or selecting a time. All that is necessary is to select an auto sensor program before starting to cook.

  • Page 18: Cautions To Be Observed When Troubleshooting

    time is then shown in the display and begins counting down. Balance of cooking (T2 time) The balance of cooking time which is called T2 time, can be calculated by the following formula. / T2 time (in sec.) = T1 time x K factor NOTE: Remember, the T1 time starts after the start pad is tapped.
  • Page 19 grounded. It is imperative, therefore, to ensure the appliance is properly grounded before beginning repair work. 8.2. Inverter Warnings DANGER, HIGH VOLTAGE AND HIGH TEMPERATURE (HOT/LINE) OF THE INVERTER POWER SUPPLY (U) This high voltage inverter power supply handles very high voltage and very high current for the magnetron tube.
  • Page 20 Inverter Grounding WARNING! DISCHARGE THE HIGH VOLTAGE CAPACITORS For about 30 seconds after the oven is turned off, an electric charge remains in the high voltage capacitors in the inverter power supply circuit board. When replacing or checking parts, remove the power plug from the outlet and short the inverter output terminal of the magnetron filament terminals to the chassis ground with an insulated handle screwdriver to discharge.
  • Page 21 voltage in the high voltage circuit including the filament voltage of the magnetron. WARNING Never touch any circuit wiring with your hand nor with an insulated tool during operation. 8.3. When parts must be replaced, remove the power plug from the outlet.
  • Page 22 MICROWAVE GENERATOR OR OTHER PARTS CONDUCTING MICROWAVE ENERGY IMPORTANT NOTICE The following components have potentials above 250V while is appliance is operated. - Magnetron - High voltage transformer (Located on inverter (U)) - High voltage diodes (Located on inverter (U)) - High voltage capacitors (Located on inverter (U)) Pay special attention in these areas.
  • Page 23 Kyldonet tillförs också höga spänningar (VARMT) och får därför inte vidröras när ugnen är ansluten till nätströmmen. Kollektorn är direkt ansluten till kyldonet. Kyldonet kan vara MYCKET VARMT av värmeenergi. Därför måste största försiktighet iakttagas vid service och byte. Fig. 1 VARNING: HÖGSPÄNNINGSOMVANDLAREN (U) MÅSTE VARA JORDAD Kontrollera att högspänningsomvandlarens strömkrets är jordad.
  • Page 24 urladdas mot chassits jord med hjälp av en isolerad skruvmejsel. Sätt skruvmejseln mot chassits jord och slut därefter kretsen mot ut -terminalerna. Fig. 3 VARNING Det förekommer höga spänningar och hög strömstyrka i högspänningsomvandlarens primär- och sekundärspolar, drossel och kyldon. Det är livsfarligt att arbeta med eller nära dessa kretsar när ugnen är under spänning.
  • Page 25 böjda, avbrutna eller på annat sätt skadade så att de inte kan hålla brytarna. 9.5. Stick inte in några spikar, trådar etc i hålen i enheten när den är i bruk. Stick aldrig in någon tråd, spik eller annat metallföremål genom lamphålen i ugnsutrymmet eller i några andra hål eller springor.
  • Page 26 om de inte hanteras med försiktighet. 10. LAITTEEN HUOLLOSSA JA KORJAUKSESSA HUOMIOONOTETTAVIA VAROTOIMENPITEITÄ Toisen kuin monet muut kodinkoneet, mikroaaltouuni toimii korkealla jännitteellä ja suurella virralla. Vaikka uuni onkin täysin turvallinen normaalikäytössä, sen korjauksessa on noudatettava ehdotonta varovaisuutta. HUOMIO Magnetronia vaihdettaessa ja sen läheisyydessä työskenneltäessä on riisuttava rannekello.
  • Page 27 Korkeajännitemuuntimen teholähdekortti on maadoitettava asianmukaisesti laitteen runkoon maadoitusliittimen välityksellä. Varmista asianmukainen maadoitus maadoituslevyn ja -ruuvien avulla. Fig. 2 KORKEAJÄNNITEKONDENSAATTORIEN PURKAMISTA KOSKEVA VAROITUS Korkeajännitekondensaattorien sähkövirtaa koskeva varoitus. Kun uunin virta katkaistaan, muuntimen teholähdekortin korkeajännitekondensaattorien sähkövaraus säilyy noin 30 sekunnin ajan.Kun vaihdat tai tarkistat uunin osia, irrota sähköpistoke pistorasiasta ja pura varaus oikosulkemalla magnetronin hehkunapojen muuntimen lähtönavat rungon maahan ruuviavaimella, jossa on eristyskahva.
  • Page 28 Korkeajännitevirtapiirin jännitettä EI SAA mitata. Tämä koskee myös magnetronin hehkujännitettä. VAROITUS Kytkentäjohtoja ei saa koskettaa käytön aikana käsin eikä eristyskahvalla varustetulla ruuviavaimella. 10.3. Kun osia on vaihdettava, irrota sähköpistoke pistorasiasta 10.4. Kun 10 ampeerin sulake on palanut oikosulkuvirtasuojan kytkimen käytön vuoksi: VAROITUS Kun 10 ampeerin ja 250 voltin sulake on palanut oikosulkuvirtasuojan kytkimen käytön vuoksi, vikavirtasuojan ja...
  • Page 29 on mikroaaltoenergiavuodon mittausta koskevassa osassa.). HUOMIO MIKROAALTOSÄTEILY VÄLTÄ ALTISTUMISTA MIKROAALTOGENERAATTORIN TAI MUIDEN MIKROAALTOENERGIAA JOHTAVIEN OSIEN TUOTTAMALLE SÄTEILYLLE. TÄRKEÄ HUOMAUTUS Seuraavien osien jännite voi olla yli 250 volttia laitetta käytettäessä: - Magnetroni - Korkeajännitemuuntaja (sijaitsee muuntimessa [U]) - Korkeajännitediodit (sijaitsevat muuntimessa [U]) - Korkeajännitekondensaattorit (sijaitsevat muuntimessa [U]).
  • Page 30 ufarlig ved normalt bruk må du være ytterst forsiktig når du utfører reparasjonsarbeid. Som du ser ligner den på en linjeslutt- transformator for fjernsyn, men strømmen er svært sterk og derfor er det fare forbundet med den sterk strømmen og de høye spenningene.
  • Page 31 ADVARSEL VEDRØRENDE UTLADNING I HØYSPENTKONDENSATOREN Advarsel om den elektriske ladingen i høyspentkondensatorene. I ca. 30 sekunder etter at ovnen er slått av er det fremdeles elektrisk ladning i høyspentkondensatorene i vekselretter- strømforsyningskortet. Når du skifter ut eller kontrollerer deler må du trekke støpselet ut av kontakten, og kortslutte utgangsklemmen for vekselretteren på...
  • Page 32 11.3. Ta støpselet ut av kontakten får du skifter deler. 11.4. Når 10 A sikringen går pga. bruk av kortslutningsbryter: ADVARSEL Når 10 A sikringen går pga. bruk av kortslutningsbryteren må du skifte ut den primære låsebryteren og kortslutningsbryteren. Du må også...
  • Page 33 - Magnetron - Høyspentomformer (transformator) (finnes på vekselretteren (U)) - Høyspent dioder (finnes på vekselretteren (U)) - Høyspentkondensatorer (finnes på vekselretteren (U)) Vær spesielt nøye med disse områdene. Når apparatet brukes med dørhengsler eller magnetron feil montert kan mikrobølgelekkasjen nå over 5 mW/cm .
  • Page 34 tilsluttet strømenheden. (Kollektoren) er direkte forbundet til aluminiumskølekappen. Aluminiumskølekappen kan være VARM fra varmeenergi, og man skal derfor passe meget på ved eftersyn og udskiftning. ADVARSEL ANG. JORDING AF VEKSELRETTERENS NETSPÆNDING (U) Check om kredsløbet for højspændingsstrøm til vekselretteren er jordforbundet.
  • Page 35 Sørg for, at berøre chassisjordingssiden først, og derpå kortslutte til udgangsklemmen. Fig. 3 ADVARSEL Der er højspænding til stede med højstrømsegenskaber i kredsløbene i primær- og sekundærviklingerne, induktansspolen og kølekappen i vekselretteren. Det er yderst farligt at arbejde på eller i nærheden af disse kredsløb, mens der er strøm på ovnen. Man MÅ...
  • Page 36 monteringstappene hverken er bøjede, knækkede eller på anden måde ude af stand til at holde på kontakterne. 12.5. Undgå at stikke søm, ståltråd o.l. gennem hullerne i enheden, mens der er tændt for den Der må aldrig stikkes ståltråd, søm eller andre metalgenstande i lampehullerne eller andre huller eller åbninger, fordi sådanne genstande kan virke som antenner og forårsage mikrobølgelækager.

  • Page 37: Parts Replacement Procedure

    FORSIGTIG Vær forsigtig under udpakning, montering eller flytning af enheden, da de afdækkede kanter kan være skarpe og forårsage tilskadekomst, hvis man ikke passer på. 13. Parts Replacement Procedure 13.1. Magnetron 1. Discharge the high voltage capacitors on the inverter circuit. 2.
  • Page 38 Screws to remove the magnetron 13.2. Inverter power supply (U) 1. Discharge the high voltage capacitors 2. Unplug the H.V. Lead wires from the magnetron 3. Remove the connector CN701 and CN702 from the inverter PCB 4. Remove the two screws holding the inverter base to the chassis (See figure 3) 5.
  • Page 39 sink because it is hot. Figure 3 Removal of the inverter PCB Figure 4 Disconnecting the PCB lock connector 13.3. Digital Programmer Circuit (DPC) and membrane key board. NOTE: Ground any static electric built up on your body before handling the DPC. 1.
  • Page 40 2. Peel away the display window from the inside of the base. 3. Remove the membrane assembly by pushing from the inside of the base and then peeling away from the outside surface. NOTE: 1. The escutcheon key board is attached to the escutcheon base with double faced adhesive tape.
  • Page 41 Note Do not use a soldering iron or de soldering tool of more than 30 watts on DPC contacts 13.5. Fan Motor 1. Disconnect the two lead wires from the fan motor terminals 2. Remove the power cord by removing the two wires from the noise filter and the ground connection from the oven chassis.
  • Page 42 instructions below for proper installation and adjustment so as to prevent excessive microwave leakage. 1. When mounting the door to the oven, be sure to adjust the door parallel to the bottom line of the oven face plate by moving the upper hinge in the direction necessary for proper alignment.
  • Page 43 Removing the Turntable motor cover Figure 9 Two screws to remove the turntable motor 13.8. Quartz Heater 1. Remove the sensor cable from the DPC connector CN7. 2. Remove the exhaust guide A by removing the two screws shown in figure 10. 3.
  • Page 44 Removing the exhaust guide and grill cover Figure 11 Removing the screws holding the grill heater Figure 12 Removing the grill element 13.9. Convection Element And Circulation Fan Motor 1. Remove one screw to remove the the exhaust guide D. Figure 13. 2.
  • Page 45 4. Remove the power cord. 5. Remove the wire terminals from the circulation fan motor and the convection heater element. 6. Remove the four screws from the oven base. Figure 15 7. Carefully place hte oven onto its base and remove the backplate. 8.
  • Page 46 Removing the oven back plate Figure 15 Removing the base plate Figure 16...

  • Page 47: Component Test Procedure

    Removing the circulation motor 14. Component Test Procedure Caution 1. High voltage is present at the high voltage terminal of the inverter unit, including the aluminium heat sink. 2. It is not necessary or advisable to attempt to measure this high voltage.
  • Page 48 secondary latch switch. 3. Test the continuity of the switches with the door open and closed with an ohm meter on the lowest scale. Normal continuity readings should be as followed. Door Open Door Closed Primary Latch infinite (Close) Switch (Open) Secondary infinite...
  • Page 49 14.4. Push Button Keyboard Check the continuity between the switch terminals, by tapping an appropriate pad on the keyboard. The keypad matrix is shown on Key Board Matrix. 14.5. Inverter Power Supply Caution DO NOT try to repair this inverter power supply). Replace as a whole H.V.

  • Page 50: Measurements And Adjustments

    NOTE: If the microwave oven has been operated allow to cool to room temperature before attempting to measure the thermistor resistance. 14.8. Humidity sensor and digital programmer circuit NN-A890WB 1. Check the resistance across the sensor heater terminals. Normal cold resistance should read approximately 4.5 ohms.
  • Page 51 mounting tabs are not bent, broken or otherwise deficient in their ability to hold the switches. - Refer to the schematic and wiring diagram to ensure proper connection 15.1. Installation of primary latch switch, secondary latch switch and short switch. 1.

  • Page 52: Troubleshooting Guide

    (Recorded as T2) 4. The normal temperature rise at the high power position for each model is shown in the table. (Figure 2) Figure 1 Adjustment of latch switch assembly RATED OUTPUT TEMPERATURE RISE 1000W 8°C 16. Troubleshooting Guide Fuses are not blown...
  • Page 54 Fuses are not blown...
  • Page 57 Other problems Inverter circuit troubleshooting Alternative method for toubleshooting the inverter circuit 17. Digital Programmer Troubleshooting Guide...
  • Page 59 How to check semiconductors 18. Exploded View 19. Main Parts List 1. Part numbers are indicated on most mechanical parts. Please use these part numbers for part orders. Do not use the description of the part. Important safety notice 1. Components identified by mark have special characteristics important for safety.
  • Page 60 use only the manufacturers specified Ref. No. Part No. Part Name & Description Remarks E00069000EP WARNING LABEL E41199000BP EXHAUST GUIDE D E10589000BP BACK PANEL COVER E605A4V20BP THERMISTER AEE9108A20GN HOLDER (P CLIP) E900C4V20GP POWER CORD SUPPLY E67597550GP FUSE 10A E607X4V20BP NOISE FILTER E400A4760JP FAN MOTOR AEE6230P10GN...

  • Page 61: Door Assembly

    E20559000BP COVER A E200A4V20BP OVEN CAVITY E09030000CD CUSHION RUBBER E22589000BP ADIABATIC MATERIAL E22379000BP LEFT HEATER PANEL E030H9000BP HUMIDITY SENSOR NN-A890WB E40249000GP EXHAUST GUIDE A E202N9000BP UPPER HEATER COVER E64179000BP HEATER BRACKET A E67579000BP HEATER BRKT D E630H9000GP CONVECTION HEATER E64189000BP...

  • Page 62: Escutcheon Base Assembly

    Ref. No. Part No. Part Name & Description Remarks E302A4V20HGP DOOR A ASSYM E30214000AP DOOR KEY SPRING E30188000BP DOOR KEY A E302K9000BP DOOR E E30859000BP DOOR C E30067300AP HINGE When ordering any door component also order door C, this part may become damaged during dissassembly of the door.

  • Page 63: Packing And Accessories

    Remarks E80724V20HBP DOOR OPENING BUTTON E80378A0AG SPRING E80344V20HBP ESCUTCHEON BASE E81274V20BP ESC BACK PLATE E603L4V20SP P C B AU NN-A890WB SPG E603L4V30SP P C B AU NN-A860WB SPG E6629-1600 RIBBON CABLE E82564V20BP DOOR OPENING LEVER E603Y4V20BP P C B DU...
  • Page 65 CRISPY PAN HANDLE E01134N80EP TRAY STYROL E060V8020BP WIRE RACK LOW 37mm E06435870GS RUBBER FOOT (RED) E01084V20EP TRAY PACKING E01024V20HSP CARTON BOX NN-A890WB E01024V30HSP CARTON BOX NN-A860WB E01059000BP LOWER FILLER E01069000BP COVER POLYTHENE E01079000BP DOOR SHEET E01049000BP UPPER FILLER 23. REF No 8 E607X4V20BP Noise Filter (U) Ref.
  • Page 66 Side strip REF Microwave Oven Model Number Bottom Strip No 2 Number REF No 1 NN-TKA80W E1603A510HBP E1601A540HBP NN-A890WB NN-A860WB Instalation Guide A0003A810BP 25. Digital Programmer Circuit Schematic 26. Key Board Matrix 27. Digital Programmer Circuit Parts 27.1. E603L4V20SP E603L4V30SP DPCAU...
  • Page 67 Ref. No. Part No. Part Name & Description J603L 4V20SP J603L 4V30SP C502 AECU1F101J50 100pF Chip Capacitor C40-C48 C110 C20 C441 C570 AECU1F103Z50 10nF Chip Capacitor C501 AECU1F103Z50 10nF Chip Capacitor C220 C221 C222 C224 C21 AECU1F104Z25 100nF Chip Capacitor C130 C500 AECU1F104Z25 100nF Chip Capacitor...
  • Page 68 27.2. E603Y4V2BP E603Y4V3BP DPC DU Ref. No. Part No. Part Name & Description J603Y 4V20BP J603Y 4V30BP ZD10 AESZMTZ5R6B Zener Diode D221-D225 AESS133T-77 Silicon Diode AESS133T-77 Silicon Diode D220 AESS1N4003E Silicon Diode AESSAK03 Shottky Diode C330 ECBT1H681KB5 680PF Capacitor C440 ECBT1E103ZF5 10nF Capacitor R25 R26...

This manual is also suitable for:

Nn-a860wb

Table of Contents