Panasonic NN-T793AF User manual

ORDERNO.SIMMC 0305020A3
MicrowaveOven
NN-T793AF / NN-T783SF / NN-T703QF
QPQ(Australia&NewZealand)
Please fileand use thismanual togetherwiththeservice manual for
Model NN-S560WF(ORDERNO. SIMMC0006012C3)
SPECIFICATIONS

2003 Shanghai Matsushita MicrowaveOvenCo., Ltd. / All
rights reserved. Unauthorizedcopying and distribution isa
violation oflaw.

1. SCHEMATICDIAGRAM
2. CAUTIONS TO BE OBSERVEDWHEN
TROUBLESHOOTING
Unlike manyotherappliances, the microwave ovenis a high voltage, high current device. Itis

free from dangerinordinaryuse, though extreme care shouldbe takenduring repair.
Caution
Servicemenshouldremovetheirwatches wheneverworking close
toor replacing themagnetron.
2.1. Check thegrounding
Donot operate on a twowire extension cord. The microwave ovenis designedto be grounded
whenused. Itis imperative, therefore, to ensure the appliance is properlygroundedbefore
beginning repairwork.
2.2. Inverterwarnings
DANGER, HIGH VOLTAGEAND HIGH TEMPERATURE(HOT/LINE)OF THEINVERTER POWER
SUPPLY(U)
Thishigh voltageinverterpowersupplyhandles veryhigh voltage
and currentfor themagnetron tube. Though itisfree from danger
inordinaryuse, extremecareshouldbetakenduring repair.
Thealuminum heat sinkisalsoenergizedwithhigh voltage(HOT),
sodo nottouchwhentheACinputterminalsareenergized. The
powerdevices Collector isdirectlyconnectedtothealuminum heat
sink.
Thealuminum heat sinkmaybeHOTduetoheat energy, therefore,
extremecareshouldbetakenduring servicing.
H.V. Inverterwarning
WARNINGFOR INVERTER POWER SUPPLY(U)GROUNDING
Check thehigh voltageinverterpowersupplycircuitgrounding.
Thehigh voltageinverterpowersupplycircuitboard must havea
properchassisground, theinvertergrounding bracket must be
connectedtothechassis. Iftheinverterboard isnotgroundedit
will expose theusertoveryhigh voltages and cause extreme

DANGER!Besurethat theinvertercircuitisproperlygroundedvia
theinverterearthbracket.
Grounding of the invertercircuitboard
WARNING!DISCHARGETHEHIGH VOLATGECAPACITORS
For about30 secondsaftertheovenisturnedoff, anelectric
chargeremainsinthehigh voltagecapacitorsintheinverterpower
supplycircuitboard.
Whenreplacing or checking parts, removethepowerplug from the
outlet and shorttheinverteroutputterminal ofthemagnetron
filamentterminalstothechassisground withaninsulatedhandle
screwdrivertodischarge. Please besuretotouchthechassis
ground sidefirst and thenshorttotheoutputterminals.
Discharging the high voltage capacitors
WARNING
Thereishigh voltagepresentwithhigh currentcapabilities inthe
circuits oftheprimaryand secondarywindings, choke coil and
heat sinkoftheinverter. Itisextremelydangeroustoworkon or
nearthese circuits withtheovenenergized. DO NOTmeasurethe
voltageinthehigh voltagecircuitincluding thefilamentvoltageof
themagnetron.

WARNING
Nevertouchanycircuitwiring withyour hand or withaninsulated
tool during operation.
2.3. Partreplacement.
Whenanypartorcomponent is to be replaced, always ensure thatthe powercordis removed
from the wall outlet.
2.4. Whenthe10Afuse isblownduetotheoperation oftheshort
switch:
WARNING
Whenthe10A250V fuse isblownduetotheoperation ofthe
interlock monitor switch, replace all ofthecomponents (primary
latchswitch, door switch, shortswitchand powerrelayB(RY1)).
1. Thisismandatory. Referto“adjustments and measurements”for
thelocation ofthese switches.
2. Whenreplacing thefuse, confirm that ithas theappropriate rating
for these models.
3. Whenreplacing faultyswitches, besurethemounting tabsare
notbent, brokenor deficientintheirabilitytoholdtheswitches.
2.5. Avoidinserting nails, wireetc. through anyholes intheunit
during operation.
Neverinserta wire, nail oranyothermetal objectthrough the lamp holes on the cavityorany
holes orgaps, because suchobjects maywork as anantenna and cause microwave leakage.
2.6. Confirm afterrepair
1. Afterrepairor replacementofparts, make surethat thescrewsof
theoven, etc. areneitherloose nor missing. Microwaves might
leak ifscrewsarenotproperlytightened.
2. Make surethat all electrical connectionsaretightbeforeinserting
theplug intothewall outlet.
3. Check for microwaveenergyleakage. (Refertoprocedurefor
measuring microwaveenergyleakage).
CAUTION MICROWAVE RADIATION
USE CAUTIONNOTTO BECOME EXPOSEDTO RADIATIONFROM
THE MICROWAVE MAGNETRONOROTHERPARTS CONDUCTING
MICROWAVE ENERGY

IMPORTANTNOTICE
Thefollowing components havepotentialsabove2000V whilethe
appliance isoperated.
-Magnetron
-High voltagetransformer(Locatedon inverter(U))
-High voltagediodes (Locatedon inverter(U))
-High voltagecapacitors(Locatedon inverter(U))
Payspecial attention tothese areas.
Whentheappliance isoperatedwiththedoor hinges or magnetron
fixedincorrectly, themicrowaveleakagecanexceedmorethan
5mW/cm2. Afterrepairor exchange, itisveryimportanttocheck if
themagnetron and thedoor hinges arecorrectlyinstalled.
2.7. Sharp edges
Caution
Please use caution whenunpacking, installing or moving theunit,
as someexposededges maybesharp tothetouchand cause
injuryifnothandledwithcare.
3. MEASUREMENTS AND ADJUSTMENTS
3.1. Adjustmentofprimarylatchswitch, secondarylatchswitchand
shortswitch.
1. MountthePrimarylatchswitch, thesecondarylatchswitchand
theshortswitchtothedoor hookassemblyas showninILL.
NOTE:
Nospecificindividual adjustmentduring installation ofthe
Primarylatchswitch, secondarylatchswitchor shortswitchto
thedoor hookarerequired.
2. Whenmounting thedoor hookassemblytotheovenassembly,
adjust thedoor hookassemblybymoving itinthedirection ofthe
arrowsintheillustration, sothat theovendoor will nothaveany
playinit. Check for playinthedoor bypulling thedoor assembly.
Make surethat thelatchkeysmovesmoothlyafteradjustmentis
completed. Completelytightenthescrewsholding thedoor hook
assemblytotheovenassembly.
3. Reconnect theshortswitchand check thecontinuityofthe
monitor circuitand all latchswitches againbyfollowing the