Panasonic NN-A880WB User manual

OrderNumberMOP00090015C2
MicrowaveOven
NN-A880WB/ NN-A850WB/ NN-A850CB
SPECIFICATIONS
1995 Matsushita ElectricIndustrial Co., Ltd. All rights reserved.
Unauthorizedcopying and distribution isaviolation oflaw.
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1. InverterWarning
Theinverterboard looks like aregularPCB, however, thisPCB drives themagnetron tubeusing
veryhigh voltages and current.
Ithas
1. Veryhigh voltageand high current
2. AnAluminiumheat sinkthat becomes veryhot
3. Thecapacitorson theinvertercircuitwill containahigh voltage
chargeevenwhentheovenisnotoperating.
Donot
1. Donottouchthecircuitryas itcontainsveryhigh voltages. When
replacing theboardplease take extremecaretoavoidpossible
electricshock. High voltages mayremaininthecircuit.
2. Donottouchthealuminiumheat sinkas itwill becomeveryhot. It
alsocontainshigh voltages.
3. DonotattempttorepairtheinverterPCB as thiscanbevery
dangerous. Replace thehigh voltageinvertercircuitas acomplete
unit. Returntheoldunitfullyrepackedintheoriginal shipping box
and completedpaperwork.
4. Donotadjust ortamperwiththepreset volumeon theinverter
board. Itisverydangeroustoadjust thispreset withoutproper
test equipment.
5. Donottest theovenwhiletheinvertergrounding striporscrews
areloose. Itisverydangeroustooperate theinvertercircuitboard
withoutaproperground connection.
Figure1
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InverterGounding
Figure2
InverterPCB layout
2. FeatureChart
Function NN-A880WB NN-A850WB
NN-A850CB
Microwave 6 6
Grill 3 3
Convection 17 17
Combination YES YES
Sensor reheat 2 -
Sensor cook 2 -
Sensor combination 4 -
Weightdefrost 3 3
Weightcombination 8 12
Weightreheat - 2
Weightcook - 2
Stagecooking 3 3
Delay/Stand YES YES
More/Less YES NO
Kg->lb/oz YES YES
Clock 12H 12H
Word prompt English English
StepbyStep LED LED
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3. Control Panel
4. Operation And Digital ProgrammerCircuit Test
Procdure
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5

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5. SchematicDiagram
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6. Wiring Diagram
7. Description of Operating instruction
7.1. Variablepowercooking control
TheHIGHVOLTAGE INVERTERPOWERSUPPLYcontrolstheoutputpowerbyasignal from the
digital ProgrammercircuitDPC. Thepowerrelay (RY1)turnson tosupplypowertotheinverter
circuit. Thelevel ofoutputpoweriscontrolledbythedrive signal level from theinvertercircuit.
NOTE1:TheON/OFF timeratiodoes notcorrespond withthepercentageofmicrowave power
since approximately2secondsarerequiredfor heating themagnetron filament. / NOTE:2If
microwave cooking isover8minutes on HIGHpower, thefanmotor rotates for 1minuteafter
cooking tocool theovenand electrical components.
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Dutycycles for microwave cooking
Output DutyON/OFF
ONtime OFF time
High 1000W 22” 0”
Defrost 440W 16” 6”
Medium 600W 22” 0”
Low 440W 22” 0”
Simmer 440W 15” 7”
Warm 440W 8” 14”
7.2. Grill Cooking
Thedigital programmercircuitcontrolsthegrill powerbyoperating thepowerrelay RY4inthe
sequence showninthetablebelow
Dutycycles for Grill Cooking
DutyON/OFF
ONTime OFF Time
Grill 1 66” 0”
Grill 2 54” 12”
Grill 3 42” 24”
7.3. Autoweightdefrost, AutoweightCook
Whenanautocontrol featureisselectedand thestartpadpressed:
1. Thedigital programmercircuitdetermines thepowerlevel and the
cooking timeand indicates theoperating state inthedisplay. The
tableshowsthecorresponding cooking times foreachcategory
and its respectiveweight.
2. Whenthecooking timeinthedisplaywindow has elapsed, the
oventurnsoff automaticallyviathecontrol signal fromthedigital
programmercircuit.
Note:Afterautocooking iftheoventemperatureisoverthe
predeterminedtemperaturethefanmotorrotates tocool theoven
and its components.
AutoWeightDefrostNN-A880WBNN-A850WBNN-A880CB
Category 1stTouch
Weight Cooking Time
Bread 100 45s
MeatItems 200 3m 40s
MeatJoints 400 6m 20s
AutoweightCookNN-A880WB
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Category 1stTouch
Weight Cooking Time
9.WholeChicken 1000 18m 20s
10.ChickenPortions 300 9m 30s
11.Beef/Lamb 500 14m 40s
12.Casserole 800 56m 40s
13.ChilledCrispyTop 300 10m
14.FrozenCrispyTop 300 14m
15.Bake Pastry 600 15m
16.Bake Cake 400 11m 40s
AutoweightCookNN-A850WBNN-A850CB
Category 1stTouch
Weight Cooking Time
1.ChilledMeal 300 3m 30s
2. FrozenMeal 300 6m 20s
3. FreshVegatables 100 2m 20s
4. Fish 100 1m
5. JacketPotatoes 200 16m 30s
6.FrozenPotato
Products 200 10m
7. WholeChicken 1000 18m 20s
8. ChickenPortions 300 9m 30s
9. Beef/Lamb 500 14m 40s
10. Casserole 800 56m 40s
11. ChilledCrispy
Top 300 10m
12. FrozenCrispy
Top 300 14m
13. ChilledPizza 200 7m 40s
14. FrozenPizza 200 10m
15. Bake Pastry 600 15m
16. FruitCrumble 500 18m 20s
7.4. Convection Cooking
1. Thedigital programmercircuitoperates thepowerrelaysRY3,RY5
and RY6inthesequence as showninthefigurebelow.
2. Whentheovenreaches apredeterminedtemperaturethedigital
programmercircuitstopssupplying powertorelayRY5, resulting
intheconvection heaterturning off.
3. Whenthetemperaturedropsbelow thepredetermined
temperature, thedigital programmercircuitsupplies powerto
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